Selectric Typewriter Service Manual
Selectric Typewriter Service Manual
Selectric Typewriter Service Manual
at Customer Engineering
SERVICE MANUAL
oe. “SELECTRIC”
TYPEWRITER
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Page Page
FUNCTIONAL CHECK SPECIAL MACHINE FEATURES
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AIT HELUIE Derek Br b.relhtis Mae NRE MAe ew e Ps 93 REMOVAL PROCEDURES
Character Selection eee eee a eee Mee) 1s. ee ose) elie, 43 Carrier and Rocker Assembly Removal ........ 226
PITECUIIG LCR eeeee Pe, 185 Carrier Return/Backspace Cable Drum
CLE EMET” ve cvcone A RRS ea ee 201 Assembly Removal — Dual Pitch .......... 230
Escapement — Single Pitch 67 Compensator Balls Replacement ............. 230
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WOER sca ee Sid Te OS TREE EN NB IS TS 145 Cycle Clutch and Cycle Shaft Removal ........ 226
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Margins and Linelock 197 Escapement Rack Removal — Dual Pitch ....... 230
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GperationaltGantral weet 26. L0F 8 79 Keyboard Interposer Removal .............. 227
Paperfeed and Index 145 Live ez Eli CURL. Gawenea ae OR a ie ee en 230
(ALRE oon a:oe? OGRLER ENE ERE 133 Margin Rack & Rail — Dual Pitch ............ 230
Ribbon Operational Shaft Removal ................- 228
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FIMMIDUOMN os tome rnmre At Os, SOW AeL 2 157 PHINTESICEVEIRETMOVAP. © 7h 20 PRI Sew a ee 228
175 Rocker Assembly Removal ...........-.++-- 226
85 Rotate Selection Differential Removal ......... 227
Shift Sees wie ee) eye aie te) we wv @ ieee « «© s « 27 Rotate Spring Replacement ..........-..----. 227
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Tabulation — Single Pitch CHORE ee OSCE CeO I She tee Ce 719 SHILA ENIOVAL enGrieoe eo sale, eine een. we 227
Tabulation — Dual Pitch 127 Tilt Ring and Rotate Shaft Removal .......... 226
ULEAD REDIAGETTIERE cos. asm a x)a Sa a 228
27-Tooth Ratchet Assembly Removal ........-. 229
54-Tooth Ratchet Assembly Installation ....... 229
PREFACE
This manual was published to be used by customer engineers and other technically oriented
individuals as a reference source to aid in servicing the “Selectric,” “Selectric” II, and Correcting
“Selectric” typewriters. This manual covers Models 7X1, 7X3, 7X5 and 8X3-8X5 and was written
with the restraint that the persons using this manual will have already become familiar with the
machine from the operator’s viewpoint.
The Parts Catalog and the Pictorial Reference/Adjustment Manual are recommended to be used in
conjunction with this manual. There are three special tools that are also required. They are the
Hooverometer, platen gauge and hand cycling wheel. The use of the Hooverometer and platen
gauge are self-evident in the adjustments that require their use. The hand cycling wheel fits into
the right end of the operational shaft and is used to operate the machine by hand to view an
adjustment or the mechanism operation. The hand cycling wheel should be turned top-to-front.
The Introduction section of the manual includes the function of the machine, applications of the
product line and any unique features or functions of the equipment.
The Functional Check section is outlined in a sequence so that all major functions of the machine
are checked for proper performance. However, this check does not necessarily follow the sequence
of operational theory adjustments within the manual. The use of the functional check cannot be
stressed too strongly and should be.used after any service has been performed on the equipment.
The Mechanism sections of the manual are divided into two parts: Operational Theory and
Adjustment. The Operational Theory part of a section contains an explanation and illustrations in
detail of how that particular mechanism operates. When it is required, the view, the model of
machine, level of design and mode or condition of the equipment is noted under the illustration.
In the Adjustment part of the section, each adjustment is written and illustrated in the sequence
that the adjustments are to be made. When an adjustment is made, all adjustments that follow in
that mechanism must be checked to ensure the adjustment did not affect an adjustment later in
the sequence. The part to be adjusted, as well as the direction the part must be adjusted, are
printed in red. When required, the view, the model of machine, level of design and mode or
condition of the equipment is noted under the illustration. There may be instances where
adjustment sequences or tolerances vary from those set forth in other related publications,
however, the publication bearing the latest date should normally be considered the most current.
The Removal Procedures section is a numbered sequence of instructions for part removals when a
detailed part-by-part removal instruction is needed. Reassembly is accomplished by reversing the
removal steps. If a detailed breakdown of an assembly is needed, the illustrations in the Parts
Catalog should be used.
INTRODUCTION
The IBM “Selectric”? Typewriter is available with film or The correcting mechanism allows the operator a choice of
fabric ribbon and features a small sphere-shaped typing two types of correcting supplies. Both types employ a
element that eliminates type clashing. The typing element is correcting type mounted on the carrier, adjacent to the
easily removed to permit changing the typestyle to best suit ribbon. If the typist chooses to use the “lift-off” correcting
the application. An impression control permits the operator tape, a unique IBM Correctable Film Ribbon must be used.
to vary the impression of the typing element. An automatic If the IBM Tech III “cover-up” correcting tape is used, an
velocity control changes the impression of the characters IBM Tech III ribbon should be used. Both types of
located in certain keyboard positions to a lighter impression correcting tapes are color coded for identification and can
regardless of the position of the impression control. A be easily installed by the operator.
stroke storage mechanism reduces typing errors by storing
the second of two rapidly typed characters until the first is
printed out. The paper mechanism remains stationary and
the element moves across the paper. The underscore,
backspace, spacebar, index key and carrier return are
typamatic keys.
INTRODUCTION
FUNCTIONAL CHECK IBM “SELECTRIC’ TYPEWRITER
23 24 25 26 27 28 30
22
ry
FUNCTIONAL CHECK
OPERATOR CONTROLS CARRIER MOVEMENT
uk Visual Inspection — Look at the machine carefully 1. Spacebar — Return the carrier to the left margin.
for any obviously loose, damaged or missing parts. Check the spacebar by first typing a series of lower
Also look for foreign material in the machine: case ‘‘n’s” separated by a space. Then, return to the
pencils, erasers, paper clips, etc. margin, roll back to the same writing line and
substitute a space for the “‘n’s”’ and the letter ‘*x”’ for
On-Off Switch — Operate the on-off switch (8) the space. You should have a line of alternate ‘‘n’s”’
several times. Switch action should be positive and and “‘x’s”’ evenly spaced.
the machine should reliably turn on and off.
Check to see that the spacebar repeats when slight
Turn the switch off. Try to depress all of the additional pressure is applied to the keybutton.
character keybuttons. All characters except the Starting at position zero, hold the spacebar in a
hyphen/underscore (12) should be locked. No repeat operation as you watch the carrier move to the
character should print when the machine is turned extreme right limit. The speed of the carrier should
back on. remain constant from position zero to position 130.
Turn the switch on and unplug the machine. Depress Backspace — Turn the paper in your machine
all functional keys: tab (16), shift (10), spacebar sideways; then, starting with the carrier at 115 on the
(13), backspace (6) and carrier return (9). Plug the front scale, type a row of “‘h’s” and ‘“‘n’s”’ alternately
machine in. The machine should start reliably under for a total of 10 characters. Now, backspace 10
this load. spaces and retype the same characters. The characters
should overlay each other.
8) Paper Insertion — Roll a single piece of paper into
your machine. It should not wrinkle or tear. Also, check the backspace in a similar manner with
the carrier positioned at 10 and 60 on the front scale.
Paper Release — Pull the paper bail (26) forward.
Notice that the feed rolls still hold the paper firmly. Check to see that the backspace mechanism repeats
Now, pull the paper release lever (29) forward. You when slight additional pressure is applied to the
should be able to easily position the paper left and key button.
right.
Carrier Return — Operate the return key (9) with the
Cn Multiple Copy Control Lever — Operate the multiple carrier positioned two, three and four inches from the
copy control lever (22) while watching the platen left margin. Check for reliable single and double line
(27). The platen should noticeably move front and space during this operation. The carrier should not
rear. The lever should not bind at either extreme hesitate at the margin or appear sluggish.
position. Return the lever all the way forward.
Check to see that only the index portion of the
Detent Release — Push the detent release lever (1) carrier return operation is repeated when slight
down. The platen should rotate freely without any additional pressure is applied to the keybutton.
detenting action. Push the detent release lever up.
The platen should now be positively detented. Index — Operate the index key (7). Check for reliable
single and repeat operation. The carrier should not
Platen Variable — Push in on the left platen knob move during an index operation.
(21). The platen should turn freely. Be sure the
ratchet on the right side of the platen does not turn. Tab — Clear all tab stops (15). Now set tabs at 55, 56,
When the knob is released, it should restore reliably. 88 and 90. Operate the tab and check to see that the
carrier stops exactly at 55, 56, 88 and 90. Make this
Margin Set — Position the carrier at 30. Move the left check several times.
margin (18) to the right until it lines up with the
carrier pointer (4). Then, operate the carrier return. Now tab all the way to the right. Hold down the tab
The margin should remain at 30. Type over to the clear keybutton and operate the carrier return. All
right margin (5). The bell should ring 10-12 spaces the set tab stops should clear automatically without
before the carrier reaches the right margin. When the excessive noise.
carrier pointer reaches the right margin, the character
keys should lock.
Ty i.
NNO
Half Backspace Lever — The half backspace lever 1. Turn the paper in your machine sideways; then,
moves the carrier one half backspace to the left when starting with the carrier at the left, type a row of
the lever is held forward. “*h’s” and ‘‘n’s’” alternately for a total of 10
characters. Now, backspace 10 spaces and type over.
Express Backspace Keybutton — ‘The _ express The characters should overlay each other. Make the
backspace keybutton moves the carrier rapidly to the check in both pitches.
left as long as the keybutton is held depressed.
Also check the backspace in a similar manner with
Detent Release Lever — This control performs the the carrier positioned in the middle and toward the
same function as on the ‘“‘Selectric’’ Typewriter; just right of the writing line.
its location is changed.
Check to see that the backspace mechanism repeats
Stencil Lever — The stencil lever slides right-to-left when slight additional pressure is applied to the
and determines whether the ribbon mechanism is in key button.
the ribbon or stencil mode.
Depress the express backspace keybutton. The carrier
Ribbon Load Lever — The ribbon load lever raises the should move to the left as long as the keybutton is
ribbon lift guides and prepares the ribbon mechanism held depressed.
to permit changing the ribbon.
SELECTIVE RIBBON SYSTEM
SWITCH PITCH/HALF BACKSPACE
I Put a single sheet of bond paper in your machine.
Ue Place your switch pitch lever in the 10 pitch mode (to With the multiple copy control lever forward and the
the rear). With the margin set at zero, carrier return impression control lever on three, make a complete
and make a strikeup of letter “‘l’s” about two inches strikeup in upper and lower case.
long.
Inspect the copy for character uniformity; that is,
Pull the switch pitch lever forward to the 12 pitch even color density throughout.
mode. Carrier return and make another strikeup
below the previous one. The machine changed pitch if Inspect the copy for ribbon flaking; that is,
the second row of characters does not align with the splattering of ribbon particles on the copy.
first row.
With a film ribbon installed on your machine, the lift
Return the machine to its 10 pitch mode and type a pattern should look like this example:
series of slashes (/). Backspace to the beginning of the
slashes; then pull the half backspace lever forward.
DUAL PITCH TAB/ESCAPEMENT Inspect the ribbon pattern on your machine. The
characters should not overlap one another and the
1: Install a sheet of paper. Clear all tab stops and reset characters should be positioned on the ribbon witha
tabs at several locations along the writing line. margin of safety at the top and bottom.
Operate the tab from the margin and type a character
at each stop. Repeat this procedure for three lines. With a Tech III ribbon installed on your machine,
The characters should line up in straight vertical inspect the ribbon pattern. The characters should
columns. overlap one another and there should be a margin of
safety at the top and bottom of the ribbon. Type
Clear the tab stops and change pitch. Make the same several lines of underscores. The typing must not
check again after changing pitches. fade.
Now, tab all the way to the right. Hold down the tab Inspect the ribbon throughout its path around the
clear keybutton and operate the carrier return. All various guides and rollers. There should be no creases
the set tab stops should clear automatically without in the ribbon.
excessive noise.
Finally, place the stencil control lever in the stencil
With the carrier at the extreme right, depress the position and type several characters. The ribbon
carrier return, then depress the tab. The tab operation should not feed or lift.
should immediately override the carrier return.
FUNCTIONAL CHECK — IBM CORRECTING “SELECTRIC”
TYPEWRITER
This functional check is designed to check the correcting Type another character. It should be in the same
mechanism on the IBM Correcting “Selectric” Typewriter. position as the original character and the carrier
should escape normally.
Refer to the IBM “Selectric”? Typewriter or “‘Selectric”’ II
Typewriter functional checks for other machine functions. Type several characters. Normal print and escapement
should resume.
Type several characters, then depress the correcting Perform steps one through four again. The correcting
key. The carrier should backspace once. tape should feed a sufficient amount that the
characters on the correcting tape do not overlap.
Restrike the last character that was typed. The image
must be completely removed from the paper or
covered up, depending on the type of correcting tape
used and the carrier must not escape.
cL
Correcting Key
MOTOR AND DRIVE OPERATIONAL THEORY \
The drive mechanism (Figure 1) supplies power to drive the The motor is allowed to approach normal operating speed
cycle shaft and the operational shaft. The motion to oper- before the clutch engages the drive mechanism. The
ate the mechanisms within the “Selectric” Typewriter is momentum developed by the motor causes the machine to
obtained through the various cams and gears which are start even though several mechanisms may have been
driven by these two shafts. tripped with the machine “OFF.”
The shaded pole motor utilizes a centrifugal motor clutch CAPACITOR START MOTOR
to provide drive to a cogged drive belt The drive belt drives Early level machines were equipped with a capacitor start
the cycle clutch hub which in turn drives both the motor. The capacitor gives the motor starting direction and
operational shaft and the cycle shaft. torque. Refer to Early Level Drive this section.
S) Switch
Motor
Drive Belt il
Print Shaft
Cycle Clutch
Print Shaft Gear Latch
Cycle Shaft Cycle Clutch Hub
Upper Idler Gear
Filter Shaft
Lower Idler Gear
Cycle Shaft Gear
Filter Shaft Gear
=
the machine through the cycle clutch pulley.
Ss
Motor Clutch Motor
Pulley Pawls Pulley
Za
SS
T4
Cycle tos
Pulley Hub ZO NJ
fa)
Level 2 Level 1
Figure 4 — Operational Cam Shaft Drive Connection
Rest Operated
Stop Lugs
Figure 2 — Motor Clutch (Right Side View) The shaft to the left of the cycle clutch pulley hub is the
cycle shaft. The cycle shaft is driven by means of a spring
clutch and only turns whenever a letter keylever is
depressed. Its rotation is restricted to 180 deg. for each
A plastic bushing surrounds the motor shaft inside the
character cycle. After 180 deg. rotation, the spring clutch is
motor pulley (Figure 3). This bushing serves to keep the
disengaged allowing the shaft to remain stationary (Figure
motor pulley from “freezing” to the motor shaft and
a:
causing the motor to fail to start.
Cycle Clutch
Pulley
Motor Pulley
Plastic Bushing
o®
Hub Assembly 69
Cycle Clutch |
Spring
Figure 3 — Motor Pulley
Restoring Cam |
Turned Up-Ear
Figure 8 — Cycle Clutch Latch (Right Side View)
V8
Cycle Clutch Spring Ss)
The cycle shaft has inertia and tends to keep turning even
though the sleeve has stopped. The result is the spring
unwinds and is expanded to a point where the hub is no
longer driving the spring. A cycle clutch check pawl is
mounted at the extreme left end of the cycle shaft on the
inside of the left casting. The inertia of the shaft expands
the cycle clutch spring and at the same time allows the
Driving Arbor check pawl to drop into its latch surface. The left end of
the spring is now fixed so the cycle shaft cannot turn back-
Driving End
wards and allow the spring to engage on the hub.(Fig. 9)
Level 1 Level 2
(Right Side View) (Front View)
Figure 7 — Cycle Clutch Mechanism Figure 9 — Cycle Clutch Check Pawl
-11-
GEAR TRAIN MOTOR WIRING
The cycle shaft gear (Figure 10) which is setscrewed to the On grounded 3 wire machines grounding conductors must
end of the cycle shaft, drives the lower and upper idler be connected as shown. On capacitor motors, capacitor
gears. The idler gears in turn deliver motion to the filter shell must be insulated from machine frame. Older level
shaft and print shaft through their respective gears. These machines have single pole switch. (Figure 12).
shafts deliver motion to the keyboard and the carrier during
each print cycle.
Ground
Pulley
Ze
Motor Mounting Bracket
-12-
EARLY LEVEL MOTOR
In the early production machines, a capacitor-start induc- MOTOR AND DRIVE ADJUSTMENTS
tion type motor is used. A three mfd. capacitor, in the
starting winding circuit, provides a starting torque for the
Cycle Shaft End Play — Adjust the collar on the shaft
to obtain .001”-.006” end play of the cycle shaft.
motor and controls the direction of rotation. The capacitor
also remains in the circuit while the motor is running. The
CAUTION: The slight end play of the cycle shaft
capacitor is mounted in a vertical position by a bracket at
ensures that it will rotate freely. Excessive play could
the rear corner of the machine. (Figure 13).
allow a coil of the cycle clutch spring to wedge
In ungrounded systems, the capacitor is isolated from the between the two hub members of the clutch causing a
power frame by a fiber insulator and nylon mounting machine lockup.
screws. The motor is insulated from the power frame by its
Cycle Shaft Collar
rubber mounting. To convert an ungrounded system to a
grounded one, three steps must be taken: (a) The two-wire
|
Check Check Ratchet
line cord must be replaced with a three-wire cord and the ~ Ratchet
ground lead must be attached to the power frame at the
| V4 Cycle Shaft |
cord clip; (b) A short jumper wire must be connected from
‘| Bearing
the motor to the power frame; (c) The capacitor must be
Tt
Add Or
grounded to the power frame by replacing the nylon Remove
mounting screws with metal ones and removing the insulat- Shim
ing material from between the capacitor and the frame of Cycle Shaft
the machine. .001°’-.006’’ .001"’-.006”
(0,03-0,15mm) (0,03-0,15mm)
(Level 1) (Level 2)
Drive Belt NOTE: Filter shaft and print. Shaft timing must be
checked after making this adjustment.
Cycle Clutch Pulley
Prin+ Shaft
Switch Lever
/ Upper Idler
Gear
Idler Gear
Studs Lower Idler
EER
——~ “Gi
Gear
my //~ co
Cycle Shaft ————»= ) 2 ((C)) 2
Gear myO): %‘ S = Filter Shaft
Se TEEY Gear
( y Gear
§
(Level 3)
Print Shaft
Adj. Radially For
1/2 — 1 Tooth
Slippage Of Clu.
Cycle Clutch Latch Spring — T-0, R-5
Pivot Pin Rotate Sel.
(Right Side View) d, Position the overthrow stop so it will allow the
cycle shaft to overthrow its latched position by
.007”-.015”’.
4. Cycle Clutch — The cycle clutch must be adjusted to NOTE: This adjustment on Level 3 machines
satisfy the following conditions: must be made with the cycle clutch tripped;
a. The spring must clear the face of the cycle then checked with the machine at rest, to pre-
clutch pulley by .004’’-.012”. vent loss of the cycle clutch spring radial adjust-
ment.
.007"'-.015""
Cycle Clutch Hub Cycle Shaft .007’’-.015" (0,18-0,38mm)
0,18-0,38mm Cycle Shaft
[PPETTIT A
Check Pawl
b. Position the collar left-to-right so the sleeve will Detented
have .010”-.015” end play.
C Cycle Shaft
010"-,015"
(0,25-0,38mm)
———_»_ =
.010"-,015"" —=}
a
.007"-,0115”
Check Pawl
Dentenited
(0,25-0,38mm) (0,18-0,38mm)
Levels 1 & 2 Level 3
(Level 3)
POWER ON ADJUSTMENT PROCEDURE This will give approximately 1/2 tooth of motion to
The cycle clutch adjustments must be obtained with the “unwrap” the spring in its rest position. Observe this
power on as outlined in the following procedure, motion at the print shaft gear by hand cycling a zero
tilt, negative five character with the power off.
Pre-Conditions:
The cycle shaft, filter shaft, and print shaft must be proper-
ly timed.
oy Drive Belt ~ Adjust the motor mounting brackets
The gear train backlash must be correct. front-to-rear to obtain a minimum amount of belt
noise. The belt must not be loose enough to allow the
The remainder of the machine must be functional. belt to jump cogs on the motor pulley. Check by
operating the carrier return mechanism and holding
a, Leave the right-hand dust shield in place while per- the carrier while simultaneously operating the shift
forming this “‘power on” adjustment. This will elimi- mechanism, This loads the motor to a point where
nate the danger of the bristo wrench being thrown failure will be most probable.
out of the machine due to the possibility of it con-
tacting the torque limiter hub, Rotation of the cycle Drive Belt
clutch pulley and drive belt does not constitute a
hazard as there are no exposed projections which
could propel the bristo wrench out of the machine,
(O0SHe Ob
Insert Here (0;20-0 38mm) a
e. At this time, check the left-to-right position of the 7. Motor Clutch Pawl Stops — Form the lug on the
cycle clutch spring. Expand the cycle clutch spring by clutch hub to obtain a clearance of .010°-.020”
pushing the LH side of the spring with a spring hook. between the tip of a clutch pawl and the pulley
The lateral position of the spring can be changed by ratchet when the pulley is manually rotated.
pushing left or right for proper adjustment with the
cycle pulley.
— Motor Pulley Ratchet
ie Rotate the print shaft a complete cycle (top-to-rear)
until the cycle shaft check pawl drops in. Back the
.010''-.020" ae Clutch Pawl
cycle shaft up against the check pawl.
(0,25-0, ee
g. Position the collar left-to-right so the sleeve will have
.010”-.015” end play.
<a Pe sais Clutch Hub
Position the overthrow stop for .007”-.015” clear-
ance and tighten the clamp screw. (Right Side View)
Level 1 Only (Metal Hub)
KEYBOARD OPERATIONAL THEORY
The keyboard is a compact, detachable unit which controls keylevers at the front. Keylever tension is supplied by flat
the selection of the specific character that will print. This is leaf springs under the front of the keylevers. The forward
accomplished through the use of keylevers, interposers and end of each spring is cupped so that the spring will maintain
bails, which provide character selection and cycle clutch its position under the keylever. Different spring tension is
release (Figure 1). supplied to the four rows of character keylevers by
auxiliary leaf springs under the keylever springs. The
A keyboard lock mechanism, controlled by the on/off auxiliary leaf springs vary in length to offset the leverage
switch lever, is contained in the keyboard and will be difference between the four rows of keylevers. This
described in this section. variation in spring tension permits a uniform operating
force for all keylevers.
All functional keylevers are described in their specific
sections of this manual. Attached to each keylever by a shoulder rivet is a keylever
pawl. This pawl is spring loaded and is in a position to
The keylevers pivot on a fulcrum rod at the rear. A guide strike the top of an interposer.
comb stabilizes and limits the vertical travel of the
wa Shouldered Pivot
Selector
Compensator ee
Tube eee
Comb
Interposer
Selector
Bails Fulcrum Rod
/
Keyléever
/
Keylever
Pawl Spring
Selector Latch.
Interposer
Keylever
Leaf Spring Pawl
Auxiliary
Leaf Spring
f a Keyboard Lock
On/Off Bail
Lock Link
KEYBOARD
INTERPOSERS INTERPOSER LATCH SPRING
Each: character keylever has an interposer located just To assure the interposer will remain depressed long enough
below it (Figure 2). The interposer is used to select the to operate the character selection mechanism, a spring latch
amount of tilt and rotate needed to bring the desired is employed. The interposer latch is a flat leaf spring
character on the typehead to the print position. The mounted to the rear keylever guide comb in a position to
interposer pivots about a large fulcrum rod through an snap forward, trapping the interposer down when it is
elongated slot at the front and is spring loaded up at the depressed (Figure 3). :
rear. The front and rear of the interposer is positioned
laterally by guide combs. The interposers are allowed to
move vertically in the rear guide comb as well as Selector Compensator
Interposer Tube
front-to-rear.
The interposers have several lugs extending from them see Interposer
(Figure 2). There are positions for eight lugs on the bottom. Latch
Seven of these lugs are used for selection. The absence or
presence of these lugs will determine which of the selector
bails will be operated. No two interposers are alike. The Selector Compensator
rear most lug is used for special applications of the Ball
machine. The wide lug in the middle is common to all
interposers. Its purpose is to release the cycle clutch A. Interposer At Rest
whenever a keylever is depressed. Mounted directly below
this lug is a cycle bail that pivots vertically. Downward
Selector
movement of the interposer forces the cycle bail to release Compensator
the cycle clutch latch pawl. Tube
Selector
Compensator
Ball Interposer Latch
Spring
Interposer
Keylever Selector
Compensator Ball Interposer Lug
End Plug
Keylever Pawl Deflected
Latch Spring
Keylever
Spring
Selector Latch
Selector CBSA
Ye x ;Oy ony
Latch Interposer
| Filter
ome
Co
hy
be |
Selector
Bails / A | a\ :
Keylever Compensator
Tube
Interposer
Cycle Bail
Keylever Pawl
Interposer
Ser Pivot BF oS
Cycle Clutch
Keeper
J
7] iges\ie
Extension SF, [ P
x
KO Cycle
Clutch
Spring = A Sleeve
Cycle Clutch
Cycle Clutch Cycle Cycle Clutch Latch
Latch Pawl Bail Link
Figure 8 — Cycle Clutch Latch Release (Right Side View — Released Position)
Interposer
Cycle Clutch
Latch Pawl
Extension
Restoring Stud
Cycle Clutch
Keeper
Cycle
Clutch
Sleeve
Nylon Restoring
Cycle Clutch Cam
Cycle Clutch latch
Link
.002"’-.004"’
(0,05-0,10mm)
Selector Compensator Tube
Cycle Clutch
Latch Pawl
Filter Shaft
Cycle Clutch
Line Lock Latch Paw! Extension Filter Shaft Gear
Interposer
Lockout Bail
Switch Lever
Filter Shaft
Bail | =
Mounting
Plate LS
Parallel Bails Vertically
To Interposers
Restoring Cam
Cycle Bail Latch Link Pawl
5) ie
because the latch pawl must be moved further in
order to trip the cycle clutch.
Cycle Clutch Keeper — With any interposer latched Mounting Screw Location
down, adjust the keeper vertically to obtain
.000’-.002” clearance between the cycle clutch latch Latch Link Pawl
link pawl and the lower side of the keeper. Then,
check the clearance with various interposers latched (Right Side View)
down.
Keylever
Keeper — O
end plug. Repeat this procedure for the left side of Keylever At (0,38-0,51 mm)
Rest
the keyboard using position zero interposer and H
keylever.
a , End Plug
Interposer
Interposer (Right Side View)
(Level 1)
With the keylever fully depressed, form the extension
J Setscrew to obtain .005”’-.015” between the interposer and the
End Plug interposer latch spring.
UO
Latch Spring
Keylever Fully
yeegee
Depressed
Interposer
(Level 2)
Vee .005"’-.015"
Interposer ee bi (0,13-0,38mm)
ae
\ /
Gakagee End Plug Seat. End Plug a
.005"-.015" C)
| (0,13-0,38mm)
Interposer (Right Side View)
(Right Side View)
12. Switch Link — Adjust the switch link clevis so the
on/off keybutton matches the slope of the keyboard
in the off position.
pate
Adj. To Match
Slope Of
Keyboard
Clee SRETRSLE>
(Right Side View)
Clevis Covers
Approx. 1/2 Threads
Lockout Bail
Bellcrank
Selector Compensator
Tube SCRE (CZ
Lockout Bail
Keyboard
Lockout
Bellcrank
Keyboard Lock Bellcrank Link
-ATIONAL THEORY
The purpose of the shift mechanism is to rotate the type- Motion of the shift bail is transferred through the shift
head 180 degrees in the counterclockwise direction, This release bellcrank and shift release link to operate the release
action places the upper case hemisphere of the typehead arm, The release arm controls the shift ratchet and clutch
near the platen for typing capital letters. Each upper case spring to allow the shift cam to rotate.
character is in the same tilt and rotate band as the lower
case counterpart, but 180 degrees from it. Depression of the shift keybutton causes the shift cam to
rotate, forcing the shift arm to move away from the power
The shift mechanism consists of a shift arm, shift cam, frame. This delivers sufficient pull on the rotate tape to
spring clutch, clutch control mechanism and interlocks. rotate the typehead 180 deg. to the upper case position.
Two keybuttons, one at each front corner of the keyboard, Releasing the shift keybutton allows the shift keylevers to
can be used to actuate the shift mechanism. A bail is used be returned to their rest position by the shift keylever
to tie the two keylevers together. The left-hand keylever spring and causes the shift cam to return home. The shift
has a lock mechanism attached to it to enable the operator arm moves toward the power frame and the spring tension
to lock the keybutton down in the upper case position. The on the rotate tape system returns the typehead to the lower
shift lock may be released by depressing and releasing either case position.
shift keybutton.
NOTE: The rotate tape and pulley system is covered under
The power to operate the shift mechanism is taken from the character selection section of this manual.
the right-hand end of the operational shaft (Figure 1).
Shift Cam
Rotate Tape
Shift
Retainer
Plate 9 ~—___ Shift
Typehead
Interlock !
Operational’ 1
Shaft Shift Cam 1
Shift Lock
Keybutton
n Shift Arm
Pie Pulley
(|
SHIFT “27
SHIFT ARM SHIFT CLUTCH
The right hand rotate pulley is fastened to the top of the The shift cam rotates only during a shift operation and is
shift arm. The shift arm pivots left to right about a pin at - controlled by a spring clutch. One end of the spring clutch
the bottom. Mid point on the shift arm is a roller that rides is anchored to the shift cam by an adjustable retainer plate.
the surface of the shift cam. In the lower case position, the The other end of the shift clutch spring is mounted to the
shift arm rests against the head of an adjustable stop screw shift ratchet (Figure 4).
on the side of the power frame (Figure 2).
The shift cam is a disc-shaped cam that has the lobe on the Shift Cam
right side of the cam rather than on its perimeter (Figure
2). Shift Retainer Plate
A button is pressed out on a section of the shift bearing
plate directly opposite the roller on the shift arm, and Shift Cam Stop
serves as a backup for the cam.
When the shift cam is operated, the high point of the cam is
Vem W Arbor
encountered and forces the shift arm away from the power Shift
Sas Beari
earing
CP
WO O
frame, rotating the typehead 180 degrees into the upper
case position.
Shift Clutch Spring
Adjustable, Adjustable
Stop Rotate Pulley Stop
Shift Ratchet
Shift Clutch
Rotate Pulley {| [fp Release Arm
O)
(Parts At Rest)
Shift Clutch
Ratchet
Shift Arm
Shift Release
Bellcrank
Shift Cam
Shift Release Outer Lug
Link
(Rear View)
(Operated)
Figure 3 — Shift Cam Backup Roller Figure 5 — Shift Chitch Mechanism (Right Side View)
SHIFT CAM BRAKE SHIFT INTERLOCK
Shift cam overthrow is a greater problem in returning the If the shift mechanism is tripped during a print character
machine to lower case than in shifting to upper case. This is cycle, the shift interlock prevents the shift from operating
due to the acceleration received from the pressure of the until the character cycle is completed. The shift interlock
shift arm roller against the receding surface of the shift operates from a cam mounted to the filter shaft. Each time
cam, To prevent excessive noise and possible parts break- the filter shaft turns, the shift interlock is positioned into
age, a raised braking surface on the shift cam contacts a the shift clutch ratchet to prevent a shift operation (Figure
shift cam brake arm. The brake arm flexes and acts as a 8).
heavy spring when returning to lower case and prevents
acceleration of the shift cam (Figure 6).
NOTE: Early level machines have a nylon shoe mounted Shift Interlock
on the shift cam brake where it contacts the shift cam. Shift Interlock Cam
Raised Braking
Surface
Shift Cam
Brake
B. Active Position
Character
2 <b Character
(>>
Interrupter ™\Interrupter
Pawl Bail
Character
Interrupter (Flat View)
Shift Cam
Eccentric
Shift Cam
Backup
Roller Shift Overthrow Stop — With all parts at rest, adjust
.001"'-.004" the shift overthrow stop to obtain .010”-.030” clear-
(0,03-0,10mm) ance between the stop and the inner lug of the shift
ratchet. Shift to upper case. The clearance must be
(Rear View) the same.
.010"’-,030"
oe (0,25-0, 76mm)
Overthrow Stop
.000‘'-.003”
(0,00-0,08mm)
| Without Washer (Right Side View)
.000’’-.001"’
(0,00-0,03mm)
With Washer
Back-up Roller Shift Brake — Adjust the shift brake to obtain
<epineemipe
.035”-.040” rise as the brake contacts the working
surface of the shift cam.
—~ .035"'-.040"
(0,89-1,02mm)
Shift Cam
Shift Brake
(Top View)
Just Bottoms
7X3-7X5
8X3-8X5 7x1
(1,02-1,52mm)
Shift Lock — Adjust the shift lock bracket vertically
so the shift lock engages just as the shift operates or
slightly afterward. The lock should not engage before
the shift release occurs. The shift lock must be
released easily by depressing either shift keybutton.
7X3—7X5 7X1
8X3—8X5
Yi. §
Shift Lock
Adjust To Lock
Just As Shift
(Right Ride View ) Clutch Operates (Right Side View)
-31-
10. Character Interrupter — Adjust the character inter-
rupter to satisfy the following conditions:
a. Adjust the interrupter pawl radially on the
interrupter bail for minimum clearance between
the interrupter pawl and the cycle clutch latch
link when the cycle clutch latch link is in the
released position and the shift is at rest.
Cycle Clutch
Latch Link
a Character Interrupter Bail
Character
interrupter
Pawl
Cycle Clutch
Latch Link
Released
Minimum
Forward u
Clearance
Character Interrupter
Bracket
Cycle Clutch
Latch Link
Character
Interrupter Bail
le Maximum Clearance
Without Releasing Cycle Clutch
Fine alignment is defined as locking and supporting the occurs, the tilt and rotate detents are withdrawn, allowing
typehead in place so that the desired character will print the selection mechanism to return the typehead to rest
clearly. In this section we will discuss how the typehead is (Figure 1).
detented and locked into position for printing. The desired
character is brought to the approximate print position in The carrier assembly is supported in front by the print
front of the platen by the selection mechanism. Just prior shaft. The print sleeve is keyed to the print shaft, causing it
to printing, the typehead must be detented in position both to turn when the print shaft rotates. The print sleeve turns
horizontally and vertically. After the print operation within two bearings in the carrier casting (Figure 1).
Rotate Detent
Typehead
Tilt
Ring
Tilt
Detent
Detent
Actuating
Support
Print Shaft
Tilt Detent
Print Sleeve
Spring
Ribbon Feed
And Detent Cam
Lower Carrier
Shoe
Figure 4 — Rear Carrier Support (Level 1)
(No Load Spring)
Load Spring
Carrier Shoe
Carrier POWEa ag
Eccentric Stud
Upper Carrier Shoe
Load Spring ‘i
Lower Shoe
Escapement
Rack
The level 2 tilt ring has an elongated hole to allow the “Tilt Ring
upper ball socket to be spring loaded to the front of the (Level 1)
machine. This keeps the tilt ring backup shoe in contact
with the inside of the element providing a more consistent
print impact.
Upper Ball
Socket
Rocker
\
|
\
1
1
|
|
Socket |
\
Tilt Ring
(Level 2) Spacer \
~
ee \
~~
~ I
ee
=~ & g ; \
~ \
SS 1
Tilt Ring oe > \
ee
'
\
|
I Rocker
Rocker Pivot
Shaft
Carrier
-35-
DETENT OPERATION
Motion to operate the detents is taken off the print sleeve
which is keyed to the print shaft and rotates 360 degrees
during each print cycle. This motion is coupled through the
detent cam, cam follower and detent actuating lever (Figure
6). The spring load on the detents causes the detent cam Rear Guide
follower to ride the surface of the detent cam. As the
detent cam follower encounters the low dwell of the cam,
the actuating lever moves to the right and allows the tilt
detent to enter a notch in the tilt ring and the rotate detent
to enter a notch in the typehead skirt. The side play in the
: Tae Front Q
tilt and rotate detents must be minimum to securely lock Guide
the typehead. This is accomplished by using detent guides ll
(Figure 6). As the print sleeve continues to rotate, the high XG
dwell of the cam is encountered. The cam follower and J
actuating lever are then driven to the left to remove the / Rotate Daten
detents from their notches. This permits the character iy
selection mechanism to return the typehead to rest. ¥
Rotate Detent A
Guide Spring oe AS
g 5
1 § Ww
Tilt { ( p
Detent Typehead-—— #A \\
Tilt Detent SHIT )
\
x 1)
Rotate Detent
< Gue
oe =
)
eee ( as \
oe a
Tilt Detent 7
Spring )
Detent Actuating ae
ver Print Shaft
Detent Cam
Follower
Vertical and horizontal alignment must be properly defined before any adjustments are attempted.
VERTICAL alignment problems exist when the letters are out of position this way. An example follows:
anbnendnenfngnhninjnkn1nmnnnonpnanrnsntnunvnwnxnynZn
ANBNCNDNENFNGNHNINJNKNLNMNNNONPNOQNRNSNTNIINVNWNXNYNZN
Fe
HORIZONTAL alignment problems exist when the letters are out of position this way.<—e
An example follows:
anbnendnen fn gnhnin jnkn Inmnnnonpngnrnsntnunvnwnxnynzn
AN BNCN DNEN FN GNHN INJNKN LNMNNNONPNQNRNSNTNUNVNWNXNYNZN
GNMENT ADJUSTMENTS Print Sleeve End Play — The print sleeve must have
.002”’-.004”’ side play.
Level 1 Predual Impression — The setscrew in the
Carrier Shoe — ribbon lift cam should first be tightened into the
dimple and the print cam adjusted left-to-right to
Level 1 — Adjust the eccentric mounting stud to obtain the print sleeve end play.
obtain .001”-.004” vertical play between the carrier
shoes and the escapement rack. NOTE: Check radial adjustment of print cam after
making this adjustment.
NOTE: This amount of vertical play assures free
Print Cam
horizontal movement of the carrier, yet restricts
.002” - 004”
vertical movement to help prevent variation in the
vertical alignment of the type characters.
Print Sleeve ‘ ?
.002"’-.004”’
(0,05-0,10mm)
-002"-.006"
Carrier Shoes (0,05-0,15mm) Rocker End Play — Adjust the rocker shaft to obtain
With Spring Pressure Removed
.002”-.004” end play. The end play exists between a
C-clip around the shaft at the right of the rocker and
(Level 2 — Rear View) a thrust washer against the carrier casting at the left
Level 3 Parallel — Loosen mounting screw on carrier of the rocker. The rocker shaft is held in place by a
shoe. Press down firmly on rear of carrier, keeping setscréw at the left end of the rocker shaft in the
carrier shoe parallel with escapement rack, tighten carrier casting. This adjustment should be kept to the
screw. minimum side of the specification with no binds.
NOTE: On dual pitch machines ensure that the
escapement pawl is centered in the escapement rack Rocker Shaft Rocker
teeth. Mounting pag Escapement Rack
C-Clip
Anchor Screw
Setscrew
(0,05-0,10mm)
Carrier Carrier Shoe
Thrust Washer
(Level 3 — Rear View) (Top View)
Tilt Tube End Play (Machines Prior To Gearless Tilt) Rotate Shaft End Play — Adjust the rotate pulley
— Adjust the tilt pulley vertically on the tilt tube to vertically to obtain .002”-.004” vertical motion of
obtain .002”-.004” end play. The tilt pulley is the rotate shaft. The rotate pulley is secured to the
attached to the tilt tube by a setscrew and a key rotate shaft by a wedging block and a setscrew. The
against a flat surface on the tilt tube. The setscrew is pulley is accessible from the bottom of the machine
accessible through a hole in the left side of the with the carrier centered over the cycle shaft and the
carrier. Move the carrier to the right and remove the machine in upper case. DO NOT rotate the rotate
tilt pulley spring and the tilt detent spring. The tilt shaft when the pulley is loose as this affects homing.
detent spring stud can then be removed through the Recheck typehead homing after making this
hole in the carrier. The holes in the carrier and rocker adjustment.
will make the tilt pulley setscrew accessible with a six
fluted wrench. The height of the tilt sector gear is
established by shimming between the gear and the
top of the yoke. This height is set to obtain minimum
backlash with no binds between the tilt sector gear
and the tilt ring gear. .002'’-.004"’
(0,05-0,10mm)
Tilt Ring
Rotate Pulley
Rotate Shaft
.002"'-.004"" Minimum
(0,05-0,10mm) Backlash
Tilt Sector No Binds (Front View)
Tilt Tube Cie
[i | nt Lee Ny
Remove Tilt Nee
ANY) ANAAAANAAAAANARY AAAN
Detent Spring
___\|7
Lal .
Rotate Pulley
Six Fluted Wrench Setscrew
(Bottom View)
Six Fluted
Wrench Remove Tilt Detent
Spring Stud
Upper Ball Socket — Rotate Detent — Adjust the front and rear rotate
detent guides so the detent will operate vertically
a, Shim the tilt ring spacer so there is no vertical with no binds, but has no horizontal movement. This
play in the upper ball socket but it is still free adjustment should be checked by half cycling a three
to rotate. tilt zero rotate character and checking for rotational
movement of the typehead. Excessive play in the
NOTE: Vertical play in the upper ball socket will rotate detent will cause poor horizontal alignment
affect vertical alignment and impression because the because the detent will not positively position the
typehead will not maintain a definite position when typehead,
printing.
On machines equipped with level 1 detent guide, this
Minimum Play adjustment can be made with the tilt ring off of the
No Binds oe Upper Ball Socket
machine. Loosen the front guide nut approximately a
half turn to assure that it will not interfere while
Tilt Ring
adjusting the rear guide. Remove the rotate detent
Spacer spring and adjust the rear rotate detent guide until a
Shim very slight amount of friction exists as the rear tip of
the detent is moved up and down. It should be noted
that the rear guide is on an angle and the closer the
detent travels to the tilt ring, the tighter it will be
wedged. Reconnect the rotate detent spring and
adjust the front guide adjusting nut until it restricts
(Right Side View) the rotate detent from being pulled to its seated posi-
tion by the rotate detent spring, then loosen the nut
b. Level 1 — Position the tilt ring spacer until the detent snaps into place. If you removed the
front-to-rear and left-to-right so that the upper tilt ring, do not reinstall at this time.
ball socket is centered in the tilt ring spacer.
NOTE: A bind in the upper ball socket can result in Rear Guide
poor horizontal alignment if the rotate detent fails to ae First)
seat in the detent notch before print occurs. A bind
can also cause the nylon roller to drop, on Rotate Detent
compensator equipped machines, during a negative
selection. Binds in the carrier area can be detected by /
manually operating the shift arm in and out with the [
typehead installed. \ Minimum
Centered Front Guide Clearance
No Binds
(Level 1)
(Bottom View)
(Level 2)
Equal Clearance
No End Play
Minimum Side Play Guide Screw No Binds
No Binds (Adj. First)
Pivot Screw
Tilt Detent
Tilt Ring
Tube Sector
Gear
.001°’-.010”
(0,03-0,25mm)
Typehead In Tilt
2 Position
Detent Cam
Hooverometer - Follower
.020"'-.035”
(0,51-0,89mm)
Print Sleeve
Detent Actuating
Lever
Detent Cam
Follower
Yoke
Roller Detent Cam Follower (Left Side View)
(All Levels) (Left Side View)
-41-
CTION OPERATIONAL THEORY
The purpose of the character selection mechanism is to The character, selection mechanism consists of two
position the typehead in the desired character or symbol submechanisms: tilt selection and rotate selection. The tilt
position for printing (Figure 1). At rest, the position of the and rotate mechanisms transfer motion through their tape
typehead is such that the middle character of the upper systems to tilt and rotate the typehead. The keyboard (see
band is in position to strike the platen. If any other char- Keyboard Operational theory) initiates the selection for the
acter is desired, the typehead must be tilted and/or rotated. amount of tilt and rotate motion needed for each individual
character.
S‘\
Rotate 3
Latches got tS
CHARACTER SELECTION
CYCLE SHAFT & LATCH BAIL The negative latch bail differs from the positive latch bail in
Drive is transmitted to the tilt and rotate mechanisms that it rises when the cycle shaft rotates, but, only if the
through three double lobed cams on the cycle shaft, the negative 5 latch is pulled forward. This will be di
positive latch bail and the negative latch bail (Figure 2). further, later in this section. Re discussed
The two positive cams operate as a pair to control the
positive latch bail. The negative cam controls the negative The selector latches, which are components of the rotate
latch bail. and tilt mechanisms, determine how much rotate and tilt
motion the typehead will receive. The two latches to the
The positive latch bail is a box-shaped frame which pivots left are concerned with tilting the typehead, while the four
on the bail shaft at the front. Located at each side of the on the right deal with rotating the typehead.
latch bail is a cam follower roller. An extension spring, at
the rear of the latch bail, applies constant upward pressure If the tilt and positive rotate selector latches remain to the
to hold the follower rollers against the cycle shaft cams. rear, under the bail plate, they will be pulled down when
Each time the cycle shaft operates, it rotates 180 degrees the positive latch bail is operated. If any latch is held for-
dnd the bail is forced down at the rear- Attached across the ward, it will not be pulled down during an operation of the
rear of the latch bail is the bail plate. The tip of the tilt and latch bail. The method of pulling the various latches for-
positive rotate latches are held at rest under the bail plate Mies is discussed under the Keyboard Operational Theory
by extension springs. ection.
Plate
Balance Arm
Tilt Latches
Cycle Shaft
Rotate Latches
-44-
TILT MECHANISM TILT DIFFERENTIAL
The purpose of the tilt mechanism is to position the type- Two tilt latches are attached at each end of a short lever by
head vertically to any of the four character bands. This is ball shouldered rivets (Figure 3). The ball shape of the
accomplished by transferring motion from the latch bail shoulders allows the latches to pivot in all directions. The
through a latch assembly, tilt arm, tilt tape, tilt bellcrank lever is attached by a double vertical link to a bellcrank.
and a tilt ring to tilt the typehead. The bellcrank pivots on a stud at the top of the differential
bracket, The connection of the double vertical link is not in
the middle of the lever, but is offset so the leverage
developed by one tilt latch is twice that of the other.
oo
Tilt Arm
Bail Plate
Typehead
Tilt Bellcrank
Tilt Latch
Assembly
Adjustable
Stud
Extension Spring
a Yoke Arms
Tilt Arm
Pulley Yoke
Rx
Tilt Arm SH
\ NS : |
Rocker Me X % a
Assembly |NR <e at = oF
© vi
Me Z <) 4
os =,"
z N ba A
ee S) Tilt Bellcrank
Tilt Bellcrank
Extension Spring
Tilt
Bellcrank
Latch Bail
Upper Ball
Rotate
Socket
Rotate Tape Shaft
Dog Bone
Rotate Arm
Lower Ball Socket
Rotate Pulley
Rotate Spring
Balance
Lever
Rotate Bellcrank
Shift Arm
Pulley
— 2p
er
( BZ
2
O
—
R-2 Latch
Neg 5 Latch
AB-
POSITIVE ROTATION The high point of the right-hand cam is 90 degress from the
Consider the positive rotation of the typehead first. The high point of the other two cams. This ensures that when
three selector latches involved in positive rotation are those the positive latch bail is driven DOWN to the active
farthest to the right under the positive latch bail. They are position, the negative latch bail can be UP in the active
from left to right, R2ZA, R1, and R2. position.
The R1 latch is used for one-character rotation and the R2 Rotate Tape
latch for two-character rotation. With the R1 and R2
latches combined, as shown in Figure 9, a positive 3 rotate
Balance Lever Rotate
character will be selected. The R2 and R2A latches are
operated for a four-character rotation. A five-character Stop Pads Bellcrank
<y2
Rotate Tape
This Point Stationary On
Rha All Positive Selections
Negative
Negative Latch Five
Balance Lever Rotate
Bail atc
Bellcrank
o (RisiosdeView)
Figure 10 — Negative Latch Bail (At Rest)
49-
When the latch is pulled forward, the bail is allowed to rise TYPEHEAD ROTATION
(Figure 12). The force which raises the bail is applied by The typehead clips securely to the upper ball socket and
the rotate pulley spring and the extension spring attached rests over a key which is pressed into the upper ball socket.
to the rotate arm. This arrangement ensures that the typehead will rotate
whenever the upper ball socket rotates.
Cycle Shaft
Right Hand The upper ball socket has a shoulder at the bottom which
Neg. 5 Latch
Cam fits into the tilt ring (Figure 14). The fit is very close yet
permits free rotary motion of the upper ball socket. The
upper ball socket is held in place by the tilt ring spacer. The
spacer is attached directly to the tilt ring and fits over a
flange of the upper ball socket. The tilt ring spacer is
shimmed to allow rotation of the upper ball socket yet
restricts up and down play. *
Lower
Ball Socket Rotate
Spring
Rotate Arm
Rotate
Bellcrank
| Rocker
se | soe Casting
i SF— 7) Rotate
& =—_ Spring
Rotate Spring
Con Retaining Plate
|
Head Play a aa —
Removed In if |
The Negative ( | |
Direction a { )
Head Play
Removed In
The Positive
Direction
Drift (Due
To Wear)
Occurs In
This Direction
Compensating {
——+B=
Arm Lf
i
1
I
\
Figure 16 — Basic Components Of The i
le Head Play
Wear Compensator
Figure 18 — Typehead Play And Homing (Rear View)
-51-
BANDWIDTH When the wear occurs in the system, the typehead drifts in
Next, let’s consider bandwidth. With the head play removed the negative direction with respect to the detent. This
in the negative direction, the greatest variation between causes the head play and bandwidth to drift in the negative
detenting of one typehead position (Figure 19A) and direction with respect to the detent. As long as this drift
another typehead position (Figure 19B) is called band- does not exceed the wear potential portion of head play,
width. It is caused by unequal adjustment of the rotate the detent will continue to fine align the typehead. Once
latch stop pads. You will note that we have now used up the wear potential is exceeded, the rotate selection that
almost 3/4 of the negative slope of the typehead notch. coarse aligns the most negative, with respect to the detent,
will fail to align the detent notch. The detent will then fail
to seat causing that character to print out of alignment
(Figure 20). From the preceding, one can see that for
optimum performance, reliability and wear potential,
bandwidth must be controlled to be as small as possible.
|
{
|
|
1
|
|
|
> Head Play
|
\ Removed In |
| The Positive
a Direction Figure 20 — Wear Potential Exceeded (Rear View)
4 leat
Uf
i Wo If you have a vertical alignment failure, first remove the
Fig. 9: A amma (heel
ee UI feta} lb hY typehead from your machine. Check the detenting on the
“Z” and “J.’’ Make sure the tilt ring is detenting properly
when the play is removed in the negative direction. Also,
make sure you check the detenting by removing the play in
the positive direction. This will tell you if the “tilt ring
play”’ is correct and, more important, if the detent is
catching on the tip of the notch. If the detent catches on
the tip of the notch, the tilt detent will fail to seat and it
will restrict the rotate detent from seating in the typehead
tooth. This will look like a “fine alignment” problem
i]
—+| |—<———Band Width although it is a coarse alignment problem. If the tilt detent
is not catching on the tip of a detent notch, but it still fails
Head Play
Removed In
to seat, you may have a “fine alignment”’ problem (Figure
3/4 Of Neg. Slope AW):
The Negative
Direction
Most problems in the tilt mechanism will show up as a
vertical alignment failure on the paper. However, the tilt
detent controls the rotate detent. If the tilt detent fails to
seat in the tilt ring, it is possible for the rotate detent to fail
Head Play
Removed In
to seat in the typehead. This could cause horizontal align-
The Positive ment failures on the paper.
. Direction
Rotate Selection
That Detents The
Most Negative
With Respect
To The Detent Taper:
Fig. B
NOTE: Shift adjustments must be correct before attempt: 4. Positive Latch Bail Guide — Adjust the guide left and
ing to make coarse alignment adjustments. Remove the right so that the tilt and rotate latches hang vertically.
typehead before beginning adjustments.
Tilt Latches
1. Preliminary Timing — Loosen the print shaft gear and
rotate the print shaft so that its keyway is in line with
the screw on the left side of the carrier casting. This
coarse adjustment assures that the detents will oper-
ate at approximately the right time in the cycle.
Rotate Latches
Positive Latch
Print Shaft Bail Guide
Keyway
5. Interposer Stop Lugs (Levels 1 & 2 Only) — Form the
selector interposer stop lugs to obtain .0017-.005”
clearance between each latch interposer’s upright lug
and its respective selector bail. This adjustment
Print Shaft establishes a fixed position for the interposers and
will directly affect selector latch timing.
Preliminary Adjustment NOTE: This adjustment does not apply to late level
machines. Refer to adjustment 3.
(Left Side View)
os7 oe ios
.001’-.005”
2. Latch Bail Shaft — Adjust the bail shaft plate so that (0,03-0,13mm)
the bail shaft is parallel to the cycle shaft.
=a
i
Bail Shaft
Plate
Selector Latch
Interposer
Stop Lug
.001’’-.005”
3. Rotate Differential Guides — Adjust the guides left
and right so that the vertical link hangs vertically.
(0,03-0,13mm)
all
Rotate
Tilt
Differential
a i
Differential
Guide
Guide
ian Fe
Stop Lug
c Minimum Clearance
CO ee =
-050’’-.060”
Aaa / (1,27-1,52mm)
Selector Latch
Selector Latch Interposer (Right Side View)
(Right Side View)
Latch Stop Pads — Form the latch stop pads by
tapping them with a hammer and screwdriver. The
b. Levels 1 & 2 — With the machine at rest, adjust latches should reset under the bail at the same time
the selector latch links so that the tips of the the cycle clutch check pawl resets.
latches overlap the bail with .005”’-.010” over-
hang. More or less overhang can cause the When adjusting the stop pads and the negative 5 latch
latches to “pop” out from under the bail stop screw, it is helpful to place a finger on the pawl
causing malselection. while observing the latches reset and at the same time
feel when the check pawl drops in.
Se =
— + ————— [Brel |
ie ice Minimum
Co
Check Pawl
aa O
—_— 4
Latch Flush
To Screw
LOX}
Level 1 Level 2
(Right Side View)
eth
i) Ve Tilt Ring
Play ™
Removed } A 5
(Level 1) (Level 2) Negative
1-7/8 — 2 \bs.
850 — 900 Grams
Hooverometer
(Rear View)
Rotate Spring Cage
Rotate Arm
Tilt Ring
Tilt Link
Rotate Arm
Check Z Check J
Equal Detent
jj
Rotate Detent
Stud
(Rear View) lee Rotate Link (Solid Arm) — Adjust the rotate link.so
the rotate detent contacts the negative slope of the
typehead .005”-.020” from the center of the notch
Balance Arm — The balance arm is adjusted to obtain when the home character is half cycled.
proper balance between positive and negative selec-
tions. Make this adjustment by first half cycling a NOTE: On machines using the solid arm, homing
““T” and observing its detent entry. Next, half cycle a should be checked on every call.
““B” while manually withholding the negative 5 latch.
This will yield a “‘cancelled B”’ resulting in the “T” 11 .005"’-.020"
being selected. Now, adjust the balance arm left or (0,13-0,51mm)
right until the detenting of the ‘“‘cancelled B’’ matches
the detenting of the ““T’’ previously observed.
Rotate Detent
Rotate Link
ees
| Balance Arm
a
(Rear View)
NOTE: Adjustments 18-22 apply to Level 1
machines only.
Z
detenting of the “M” and ““W” while changing the Damper
stud’s position. When the detenting is equal, the stud Spring
is correctly positioned.
+5—5 ae Damper
Spring Stop
(Front View)
Rotate Arm Eccentric Stud — (Level 1 Only) (Upper 21. Damper Spring Stop (Level 1 Only) (Upper Case) ~
Case) — Half cycle -5 character and raise the nylon Adjust the damper spring stop vertically so the
roller in its slot to ensure it is not restricting the damper spring will just collapse against the power
rotate arm, Adjust the eccentric stud rotationally so frame with a -5 character half cycled and the type-
the rotate detent contacts the negative slope of the head removed.
typehead .010”-.020” from the center of the notch.
This adjustment allows the greatest amount of wear
potential available before a failure can occur.
Spring Collapsed
Damper Spring
|___.010”.,020"
Rotate (0,25-0,51mm) (Typehead Removed)
Arm Upper Case
Eccentric Half Cycled
Stud -5 Character
Damper Spring
Stop
-3 Detent = -5 Detent
(Front View)
Stop Screw
Rotate Link
Print Shaft
Touches
Eccentric Rotate
Arm Assembly
Break Off
This Lug
Front View
Replace This
New
Position
The purpose of the switch pitch mechanism is to perform approximately the same position in the machine as the
the necessary switching operations within the escapement single pitch escapement and margin rack teeth. Both the
and margin mechanisms to allow the dual pitch “Selectric” margin and escapement mechanisms function in the same
Il Typewriter to function properly in either 10 or 12 pitch. manner as the single pitch “‘Selectric’” Typewriter. There-
Both the escapement rack and margin rack are rods with fore, in order to switch pitch it is only necessary to rotate
teeth cut into two sides. Ten pitch teeth and 12 pitch teeth the racks until either the 10 pitch teeth or 12 pitch teeth
are cut into opposing sides of the racks. The racks are face the rear of the machine and engage the escapement
retained in cutouts in the escapement and margin rails. This pawl and margin slider (Figure 1).
puts the escapement rack teeth and the margin rack teeth in
Escapement
Pawl
re 10 Pitch
aN S Teeth
Kind Jos
gq ie
Escapement
Rack
12 Pitch
Teeth
Margin Slider
SWITCH PITCH
ESCAPEMENT RACK ROTATION The escapement rack gear stop lug controls the two rest
The escapement rail is screwed to the power frame in the positions of the escapement rack. In the 10 pitch mode, the
same manner as the single pitch ‘Selectric’? Typewriter stop lug is spring loaded against the half backspace lever
escapement rack. The horizontal rest position of the escape- mounting stud by the escapement rack gear toggle spring.
ment rack is controlled by a pin that is pressed into the When the gear is switched to the 12 pitch mode, it toggles
right end of the escapement rail. The left end of the escape- over and the stop lug is spring loaded against a lug on the
ment rack extends through the escapement rack bearing escapement rack bearing plate (Figure 4).
plate which is mounted to the left side of the power frame
(Figure 2).
et 12 Pitch
Gear
Switch Pitch
Lever
c
E scapem ent Rack
Multiple Copy Control
Shaft
Margin Rail
Escapement Rack Gear
SX Margin Rack
Margin Rack
Bushing
Figure 3 — Escapement Rack Gear And Switch Pitch Figure 5 — Margin Rack Mounting
Sector Gear (Left Rear View) (Left Rear View)
62-
The margin rack is rotated by the margin pitch link and the
margin rack gear. The teeth of the margin pitch link engage SWITCH PITCH ADJUSTMENTS
the teeth of the margin rack gear which is setscrewed to the
left end of the margin rack. The rear end of the margin
1. Switch Pitch Lever — Adjust the retainer for
pitch link is mounted to the escapement rack gear. As the .001”-.005” end play of the switch pitch lever.
escapement rack gear is rotated, the margin’ pitch link
moves front-to-rear rotating the margin rack gear (Figure
6).
ple
.001’’-.005”
| (0,03-0,13mm)
(Rear View)
The two rest positions of the margin rack gear are con-
Half Backspace Lever
trolled by two stops on the margin pitch link guide bracket.
Mounting Stud
A lug on the margin rack gear is toggled and spring loaded
against the stops in the same manner as the escapement
rack gear (Figure 7). 10 Pitch Teeth
Vertical
Escapement
Se << Rack Gear
Stop Lug
.005"-.010”
Gear Stop Lug
(0,13-0,25mm)
Escapement Rack
le Escapement Rack
Bearing Plate
Rear View)
Figure 7 — Margin Rack Rotation
(Left Front View)
Escapement Rack Gear Lower Stop — Form the 5. Margin Rail Horizontal — Form the margin release
escapement rack gear lower stop so the 12 pitch bracket so the margin rail rests on a horizontal plane.
escapement rack teeth are vertical when the escape-
ment rack gear stop lug is against the stop.
Margin Release Bracket
12 Pitch Teeth
Vertical
Margin Rail
Rear Stop
Margin Rack
Gear Stop Lug
Escapement Rack
Gear Stop Lug
6. Overbank — With carrier at the left margin, position
the overbank guide left or right for .001”-.005” be-
SeRP;
<=
tween the carrier stop latch and the left margin stop
in the 12 pitch mode. In the 10 pitch mode, the
clearance must not exceed .015”’.
Escapement Rack
Gear Lower Stop
Escapement
8, 4 Rack Gear
Switch Pitch
Sector Gear ——
Nal
Escapement Rack Bellcran k 001-010"
Gear Stop Lug
Margin Rack Held (0,03-0,25mm)
To The Left
(Right Side View)
Margin Pitch Link Guide Bracket — With the machine 10. Front Margin Rack Gear Stop Form the front
in the 12 pitch mode, mesh the first tooth of the margin rack stop lug so the 10 pitch margin rack
margin pitch link with the first tooth of the margin teeth are vertical in the 10 pitch mode.
rack gear, Adjust the margin pitch link guide bracket
up or down for .005”-.010” clearance between the
guide bracket lug and the top edge of the margin 10 Pitch Teeth
pitch link. This allows the margin pitch link to have Vertical
minimum backlash and not bind with the margin rack
gear.
12 Pitch Teeth
Vertical | Margin Rack
-~—~
pe N
\
4
__SGy_ SS ~
Margin Rack
Gear Stop Lug
Rear Stop
Bushing
| |ee OO 005t
(0,03-0,13mm)
(Front View)
-65-
ESCAPEMENT OPERATIONAL THEORY (SINGLE PITCH)
The purpose of the escapement mechanism is to control the Power to operate the escapement mechanism is taken from
single space movement of the carrier during each print cycle a double lobed escapement cam mounted on the filter shaft
(Figure 1). just inside the right-hand power frame (Figure 1). Bach
time a cycle occurs, the filter shaft rotates the cam 180
The carrier is under constant mainspring tension. At rest, degrees.
the escapement pawl, which is mounted on the carrier,
engages the escapement rack and prevents the mainspring The escapement cam follower pivots on a shaft just to the
from pulling the carrier to the right. During an escapement rear of the escapement cam. A trip link extends to the rear,
operation, the pawl is temporarily removed from the rack from the cam follower to the trigger lever.
and the carrier moves to the right under mainspring tension
until the pawl engages the next tooth on the escapement Each time the filter shaft turns, the escapement cam fol-
rack. lower will pivot, pulling on the trip link, causing the trigger
lever to rotate about its mounting shafts.
Backspace Paw!
Escapement Pawl
=
Backspace Rack
Torque Bar
Carrier Return Backspace Pawl
Cord
Om
Trip Link
Mainspring
oe “a
> Z Trigger Lever
i
- my &
“ |
i G
Escapement
Carrier <4 (< Ss See
il aie
Escapement/Tab ; ae .
0 hy
Cord
c=
rae
\
yer"
Filter Shaft
Escapement Cam
ESCAPEMENT -67-
TRIGGER OPERATION
An escapement trigger is mounted on the trigger lever
(Figure 2). The trigger has hooked-shaped lugs that rest
above a lug on the right end of the torque bar. During each
escapement operation, the rotation of the trigger lever Escapement Torque Bar
causes the trigger to move downward. This downward
movement of the trigger causes the torque bar to rotate.
The pivot point of the torque bar is near its bottom edge.
The escapement pawl and the backspace pawl each have a
lug that extends down just behind the torque bar. As the
top of the torque bar pivots to the rear, it will force the Trigger Lever
lugs of the pawls to the rear causing the tips of the pawls to
clear their respective racks.
Trigger Knockoff Screw
Backspace
Rack
Backspace Paw!
Escapement Pawl
Escapement
Pawl
Escapement Rack
Trigger Lever
Pivot Backspace
Escapement
Stud Paw!
The carrier is always being pulled to the right, and the pivot
stud is against the right edge of the elongated slot in the NOTE: The carrier and escapement pawl must be moved to
pawls. the left for a backspace operation. Because the backspace
pawl is mounted to the escapement bracket, movement of
Figure 4 shows the torque bar operated. The pawls have the backspace pawl to the left forces the carrier and escape-
been pulled free of their racks and the spring tension has ment pawl to the left. The backspace pawl is mounted just
pulled the pawls to the right before the carrier has started above the escapement pawl, but its tooth extends below the
to move. escapement pawl and is held engaged with the backspace
track by a small extension spring.
Backspace E (
scapemen The backspace rack is mounted to the rear of the power
Pivot: Pawl Paw i Torque Bar
frame by shouldered screws through elongated holes in the
Stud
rack. This mounting arrangement allows lateral movement
of the rack. Movement of the rack towards the left forces
the backspace pawl to the left to cause a backspace opera-
tion.
Backup Stud
Trigger Lever
ef SS
Trigger
Torque Bar
Escapement Cam Restoring Spring
Restoring Spring ~ i aa
Trigger
Cam Follower Lever
Cam Follower ;
Trigger Knockoff Screw Forces
Top Of Trigger To Rear
Escapement Cam
#4.
CARRIER MOVEMENT The carrier return cord is wound in the opposite direction
The mainspring is mounted near the back of the machine around the carrier return cord drum, passes around two
and engages the escapement shaft (Figure 10). pulleys and connects to the left side of the carrier.
The escapement shaft extends forward through a backplate Mainspring tension is applied to the carrier through the
and the power frame. Located on this shaft are two drums. escapement tab cord to move the carrier to the right during
The escapement/tab cord is wound several turns around the an escapement operation. As the escapement cord drum
escapement cord drum, then to the right over a guide roller takes up cord, the carrier return cord drum plays out cord.
just prior to passing through the right side of the machine. This allows the tension pulley to maintain constant tension
The cord passes around a tension pulley and back through on the carrier and also allows the mainspring to be rewound
the power frame and connects to the right-hand side of the during a carrier return operation.
carrier.
Carrier Return
Cord
Pulleys
Guide Roller
Mainspring
Backplate
Carrier
Escapement/Tab
Cord
Escapement Cord
Drum
Tension Pulley
Carrier Return
Cord Drum
Escapement Shaft
In the dual pitch escapement mechanism, the vertical Dual pitch escapement functions in the same manner as
position of the escapement pawl is critical. The pawl must single pitch escapement. The only differences are the
be centered in the escapement rack within the opening in escapement rack (covered in the Switch Pitch Section), the
the escapement rail. An escapement pawl guide bracket is escapement pawl and its mounting, and some adjustments.
mounted above the escapement pawl. The escapement pawl
guide lug extends down from the bracket and is formed Dual pitch machines use a steel cable in place of the nylon
under the escapement pawl to control its vertical move- carrier return cord. Early level dual pitch machines use a
ment. The escapement pawl vertical position is controlled steel cable for both the carrier return cord and the escape-
by the vertical position of the carrier, which is adjustable. ment cord.
This is accomplished by a diagonal elongated mounting slot
in the rear carrier shoe. As the carrier shoe is adjusted left Escapement Rail
or right, the rear of the carrier is raised or lowered (Figure
1). Elongated Slot Escapement
Rack
Carrier Shoe
:
Carrier —_f
Carrier Return
Cable
) Le
o-—_— Escapement
J Pawl
Escapement
Rail
Mainspring
Trigger Lever
Escapement Bh
Carrier Torque Bar a
Escapement/Tab
Cord
Filter Shaft
Cam Follower
Power Frame
Escapement Cam
= : Trip Link
Figure 1 — Escapement Mechanism
ESCAPEMENT ADJUSTMENTS (SINGLE & DUAL PITCH)
NOTE: Before any adjustments are performed in this 3. Escapement Pawl Guide Lug (Dual Pitch Only) —
section, switch pitch adjustments must be correct. Form the escapement pawl guide lug for .001”’-.004”’
clearance between the lug and escapement pawl.
I. Escapement Rack (Single Pitch) — With the print
shaft rotated so the keyway is down, position the Escapement Pawl
platen gauge to rest on the print shaft and the escape-
ment rack. The preliminary position of the escape-
ment rack is the distance spanned by the gauge plus
.030” (use pusher end of springhook). Adjust the
escapement rack to this dimension and parallel to the
print shaft. Readjust if necessary to ensure that the
backspace pawl clears the backspace rack by a greater
.001‘’-.004" :
(0:03-0,10mm) | SeePementPaw! Guide Eup
amount than the escapement pawl clears the |
escapement rack during pawl release functions.
Platen Gauge
ee Escapement Rack
Carrier Shoe (Dual Pitch Only) — Adjust the carrier
shoe left or right to center the escapement pawl in
MK,
Do 3
\. the opening of the escapement rail.
Print Shaft
oe
.030”
<—_ emae OOM), NOTE: After making this adjustment, check carrier
movement along the full writing line. The carrier shoe
(Right Side View) <=> could cock when tightening the mounting screw and
cause the carrier to bind.
If the platen gauge is not available, the escapement
rack position may be set from the No. 1 scribe line on ~ Escapement Pawl
the Hooverometer. It should just span the distance Centered Carrier Shoe
from the print shaft.
.001"
[+ (0,03mm)
At Closest
,030" Point
(0,76mm) (Dual Pitch Only)
(Right Side View) (Right Side View)
6. Escapement Bracket (Single Pitch) — Position the 7. Escapement Torque Bar (Level 1, Single Pitch) —
escapement bracket to parallel the tab torque bar Adjust the escapement torque bar .005’’-.010” end
with .011°-.017” clearance. Be sure this clearance is play with the escapement trigger centered on the
not observed at the boss on the escapement bracket. escapement bar lug,
Trigger ad
(Top View) Side Frame
(Level 1 Top View) Machines equipped with a formable lug on the left-
hand end of the escapement torque bar should be
Tab Torque Bar adjusted for .002’’-.006” clearance between the rear
of the torque bar and the lug on the escapement pawl
with all parts at rest.
.002"’-.006”
(0,05-0,15mm)
(Level 2 Top View)
(Level 2)
Escapement Pawl
Parallel Within .005”
(0,13mm)
Escapement Bracket
Maintain—=| =
.008’'-.010"
(0,20-0,25mm)
Across Touches
Writing
Line
(Rear View)
O
—} Trigger Lever
Loosen Nut
And Turn Link .001''-.005”"
(0,03-0,13mm) (Rear View)
Low Point (Right Side View)
Machine At Rest
yo
18. Escapement Shaft Collar (Dual Pitch Only) — Adjust The position of the pulley ensures that it will not
the escapement shaft collar for .001”-.004” end play contact the cover as it compensates for the cord
of the carrier return/backspace cable drum on the stretch.
escapement shaft.
CAUTION: Be sure to remove all end play from the
escapement shaft before tightening the carrier return
cord drum. End play is removed by holding the
escapement shaft forward while the cord drum is
Carrier Return/Backspace moved to the rear against the rear bearing. Hand or
Cable Drum power cycle, then recheck adjustment with the carrier
at the extreme right-hand margin.
.001''-.004"'
Carrier Return -
(0,03-0,10mm) Cord Drum
“tals
(Top View)
Pin Horizontal
And Above Center Ae
Right-Hand
Cable Pulley
21. Cord Tension — With the cords properly threaded,
adjust the carrier return cord drum so that the outer
| .040°'-.050"
edge of the nylon pulley bracket lines up with the Stop Stud (1,02-1,27mm)
scribe line on the mounting bracket.
(Top View)
ERATIONAL CONTROL OPERATIONAL THEORY
The operational control mechanism contains all of the parts machine components so that only the desired operation will
necessary to initiate the spacebar, backspace, carrier return take place and to release one of the two cams so that power
and index operations. will be supplied to that mechanism.
The operational theory for each of the four operations The two operational cams are located on the right side of
outlined above is covered in detail in their respective the operational shaft just inside the power frame. The
sections of this manual. The operational theory and left-hand cam is a double lobed cam which turns 180
adjustments in this section will apply to all of the degrees during each cycle. Its purpose is to power the
operational control mechanisms. The operational control spacebar and backspace mechanisms. The right-hand cam is
mechanism consists primarily of four interposers and an a single lobed cam which rotates 360 degrees during each
operational cam assembly (Figure 1). Each interposer cycle. It powers the carrier return and index mechanisms.
performs the same basic function — to condition the
Spacebar/Backspace
Cam
Carrier Return/
Index Cam
Cam Pawl
Operational
Shaft
Keylever
Pawl
Operational
pod
o
e
|
Power Frame
Interposers
Operational
Keylever Interposer Latch Plate
Clutch
Ratchet
Operational Operational
Clutch |nterposer
X Shaft
Release Extension
Key lever
Pawl Cam Follower
Operational
Latch
|nterposer
eS Wencauns oe |nterposer
I nterposer Lug Spring
Latch
CAM FUNCTIONS
The rotation of the operational cam assembly performs two detailed description of each operational function,
functions (Figure 3). starting at the operational latch, can be found in its
respective section of this manual.
i; The cam follower follows the camming surface of the
operational cam from the low point to the high point. The operational cam follower also contacts the
This causes the cam follower to pivot around its interposer restoring lever and causes it to restore the
mounting shaft, pulling down on the operational operational interposer forward, allowing the
latch. (The power to operate each of the operational interposer latch to relatch on the interposer latch
functions is taken from an operational latch. A plate.
Cam Follower
Cam Pawl
Operational Latch
Mounting
Keylever
Pawl
Interposer
I nterposer
Restoring
Latch Interposer Lever
Clutch Release
Release Point Of Single Operation
Arm
Keylever Pawl
Uae (aes Deflected Forward
Check Pawl
Operational Spacebar/
Ratchet Backspace Cam
Check Ring
Check Paw!
I nterposer
Cannot
Latch
REPEAT OPERATION
Repeat operation of an operational mechanism can be Repeat Operation
accomplished by preventing the interposer from relatching
against the interposer latch plate (Figure 6). A second lug,
called the repeat lug, on the keylever pawl is used to
prevent the relatching of the interposer when a keylever is Figure 6 — Keylever Pawl Operation
depressed in the repeat zone. In the case of carrier return, (Right Side View)
the repeat lug on the keylever pawl is formed to the right
above the index interposer. Depression of the carrier return
keylever into the repeat zone causes the index interposer to
be released, resulting in additional linespacing.
Keylever
Pawl
Parts At Rest
81-
3. Carrier Return Pinion Backlash — Adjust the
OPERATIONAL CONTROL ADJUSTMENTS
escapement cord drum gear front-to-rear to obtain
.002”-.004” backlash between the carrier return
1. Operational Shaft Support — Adjust the operational pinion and the escapement cord drum gear.
shaft support front-to-rear to support the operational
shaft with no binds. NOTE: Recheck adjustment No. 1 after making this
adjustment.
NOTE: Bearing centered on support.
Bearing Escapement
Cord Drum
.002"'-.004"’
(0,05-0,10mm)
Backlash
Carrier
Return
Pinion
2. Operational Shaft Position And End Play — Position 4. Carrier Return Pinion Side Play — Adjust the torque
the operational shaft laterally so the crown surfaces limiter hub left or right so there is .002’-.004”
of the escapement cord drum and the carrier return clearance between the carrier return pinion and the
pinion are even while maintaining .002’-.004” end torque limiter arbor.
play of the operational shaft. On the Model 7X1, this
adjustment is controlled by the operational cam Torque Limiter Hub
ratchet and the shift clutch arbor. On longer
machines, the position is controlled by a collar
screwed to the operational shaft and the shift clutch
arbor.
Teeth Matched
Escapement
Cord Drum
Collar
7X5
.002"'-.004"’ ge
(0,05-0,10mm)
-82-
6. Keylever Pawl Overlap — Adjust each keylever pawl Level 1 — Adjust the spacebar keylever with the
guide so the keylever pawls overlap their respective eccentric for a clearance of .005’-.015”
interposers by .0357’-.045” with both parts at rest. between the keylever pawl and the interposer.
The index keylever pawl guide should be adjusted for
.040°-.060" overlap. This overlap ensures proper Eccentric renal
? os Se pacebar
nana salIne
repeat/nonrepeat operation.
O
“i Keylever Pawl
Spacebar .005"-.015”
I nterposer
All Others .020’’-.030’
(0,51-0,76mm)
(Level 2) (Right Side View) NOTE: Both the check ring mounting studs must be
loosened before making this adjustment.
Check Ring
th Keylever Pawl To Interposer Clearance — Eccentric
Interposer Latch
Plate
Index
.030''-.035'*
(0,76-0,89mm)
Clutch Release
Interposer
Restoring Bail
(Right Side View)
-030"'-.040" t
(0,76-1,02mm)
Interposer Adjusting Screws — Adjust the three
(Right Side View)
interposer adjusting screws so a front-to-rear
clearance of .005”-.015” exists between all the
The operational cam assembly should be positioned operational latches and their respective cam
left-to-right so that the clutch release arm for both followers. Adjust the index interposer adjusting screw
the single and double lobed cams will take an equal to match the approximate position of the other
lateral bite on its respective clutch wheel. adjusting screws.
Operational Latch
Cam Follower
(Bottom View)
.030"-.040"
(0,76-1,02mm)
(Right Side View)
SPACEBAR OPERATIONAL THEORY
The purpose of the spacebar mechanism is to provide a the spacebar keylever. As the spacebar is depressed, a lower
means of moving the carrier to the right one space at a time lug of the keylever pawl contacts the operational
without printing. The spacebar is mounted at the front of interposer,
the keyboard on a pivot shaft (Figure 1). Depression of the
spacebar causes the pivot shaft to rotate and in turn rotates When the operational interposer is released, it releases the
spacebar/backspace cam and positions the spacebar latch
under the rear of the cam follower. The theory of operation
for the entire operational control mechanism is covered in
that section of this manual.
Cam Follower
Spacebar Latch
Carrier
Spacebar/Backspace
Cam
yx SEEN
otTA)
Spacebar
“=
Sak
SPACEBAR
SPACEBAR OPERATION
Movement of the cam follower pulls the spacebar latch
down, which causes the spacebar latch lever to pivot
(Figure 2). An adjusting screw on the latch lever contacts
the trigger lever, causing the trigger lever to rotate about its
pivot pin. This causes the trigger on the trigger lever to
rotate the escapement torque bar and allow the carrier to Pivot Shaft
complete an escapement operation in the same manner as a (Pin)
character print escapement.
Escapement Torque Bar Adjusting
Screw
Spacebar
Latch Lever
Tae <<
Lever
Spacebar Latch
Trigger
Carrier
lige.
Les
or >
Trigger Lever
Spacebar Latch
Spacebar Cam
SRN
\ Movement Of Spacebar Interposer
Le
(Active Position)
\ Spacebar
Lockout Cam
\ Interlock Cam
Blocks Path
Of Interposer
With Filter
Shaft Actuated
(Right Side Filter
View) Shaft i
Spacebar
Interlock Interposer
I nterposer
(Rear View)
Interlack= =. >
Bracket
Figure 5 — Spacebar Interlock (Level 1 — Lockout Actuated)
Adjustable Spacebar Interposer
The interlocks described above are called print-to-space
Stop (Rear View) interlocks, This is because the print cycles supersede the
spacebar cycles. This type of interlock is necessary in case
Figure 3 — Spacebar Operation & Print-To-Space Interlock the operator initiates a spacebar cycle too soon after a
character print cycle.
-87-
SPACEBAR ADJUSTMENTS
NOTE: All operational control adjustments must be Spacebar Link (Dual Pitch) — With the escapement
correct before attempting to make any spacebar trip link properly adjusted, adjust the spacebar link
adjustments. for .001” - .012” between the clevis pin and the
bottom of the slot in the trigger lever.
1. Operational Latch Height — Adjust the latch
adjusting screw so the spacebar latch will pass under Trigger Lever Slot
the cam follower with a clearance of .001”-.015”’.
slp
ae Spacebar Link
.001"'-.015"
(0,03-0,38mm)
(Left Side View)
1/16"-1/32”
2. Spacebar Latch Lever Screw — Adjust the screw so (1,59-0,79mm)
that .007”-.010” clearance exists between the
escapement trigger and the escapement torque bar.
Disconnect the escapement trip link before making
this adjustment. The trigger upstop should be moved
up out of the way when making this adjustment.
After completing the adjustment, the upstop should
be readjusted so it clears the trigger level by
.001°’-.005”’.
' - peak
4 Escapement Trigger = Sea
. RS oy.
\
oF
.001°’-.005" .005''-.010"
(0,03-0,13mm) (0,13-0,25mm)
; Trigger
Upsto uarud 27
Sogae a SP) 2 Upstop (Level 3)
Escapement Trigger Left Si 5
(Right Side View)
(Rear View) [Pest ide Ty)
-88-
Spacebar Guide (Levels 1 & 2) — Adjust the spacebar 6. Spacebar Repeat Stop — The additional load of the
guide for free travel. repeat stop should be applied to the spacebar just
after a single operation occurs. Adjust in the
following manner:
.001”-.005”
(0,03-0,13mm)
es
Arm ——__ ~~
at
: Stop
Horizontal
VU Repeat
{2 Spring
Repeat
Stop Screw
.0017’-.005”’
(0,03-0,13mm)
(Level 1) (Right Side View)
“> _ -— 3 Ounces
|. 85 Grams
(Bottom View)
- Repeat Stop
:
Single Function
Spacebar Keylever
Spacebar
Stem
(Level 1 — Right Side View) (Level 2 — Left Side View) .020"-.025" Interlock Stop
(0,51-0,64mm)
(Right Side View)
Escapement
Cam
Spacebar Interlock
Interposer
(Rear View)
Machine At Rest
Interlock Bracket Interposer Released
.040"'-.050” Lockout Cam
(1,02-1,27mm) Guide
Spacebar | nterposer Spacebar
Interposer
Adjustable Stop
Interlock Bracket
(Rear View)
.001''-.010”
(0,02-0,25mm)
\RRIER RETURN OPERATIONAL THEORY
The purpose of the carrier return mechanism is to return During a carrier return operation, several things occur: The
the carrier to the left margin (Figure 1). The index mechan- escapement torque bar is rotated to remove the escapement
ism is activated during each carrier return operation to line and backspace pawls from their respective racks. The carrier
space the paper. The carrier return and index operations return spring clutch is activated to drive the carrier to the
leave the carrier in position for printing at the beginning of left margin. The carrier return mechanism is latched in its
the next line. active state to ensure the carrier is driven to the left margin.
When the carrier reaches the left margin, the mechanism is
NOTE: The index mechanism is discussed in the Paper unlatched.
Feed and Index Section of this manual.
Backspace Pawl
Escapement Pawl
Escapement
Torque Bar
Carrier Return
Cord
Carrier Return
Cord Drum
Carrier
Left
Margin Stop
Margin Stop
Bracket
Carrier Return
Spring Clutch
ads Carrier Return
Latch Keeper
Unlatching Link
Guide Roller
Carrier Return
Clutch Arm Left Operational Carrier Return
Pivot Pin Latched Position
Carrier Return
Cord Drum Clutch Latch
; Escapement
Carrier Return =Torque Bar
Lever
Shoe Actuating
Arm
Torque
Carrier caee
Limiter
Clutch Arbor arrier Return
Hub
Spring Clutch
Nie
Carrier Return Carrier Return ZO cas
Clutch Shoe Pinion Gear
a <\ | a y
Carrier Return
Clutch Latch
: Carrier
“BS | : Latch Actuating Arm
iN Ca Return
’ (Ge Actuator Escapement
at Arm Shaft Carrier Return
imiter we Pini Carrier Return Operational Latch
Spri f inion
pring Spring Gear Operational Cam
Clamp
Cam Follower
Carrier Return —~ Escapement
Clutch Spring Cord Drum
Carrier Return
Clutch Arm
Stud & Spring Opeational
Shaft
Bracket
\ Carrier Return
Latch Keeper
\
Overbank Guide \
Unlatching Link
Bellcrank
TORQUE LIMITER between this loop and an eccentric stud on the torque
If the carrier is already resting at the left margin when a limiter hub. The extension spring increases the force
carrier return operation is initiated, the carrier return required to unwind the torque limiter spring so that no
mechanism must be allowed to slip in order to reduce strain slippage occurs during normal carrier return. The torque
and prevent parts breakage. To accomplish this, rotational limiter spring slips when the carrier cannot move to the left.
motion of the operational shaft is supplied to the carrier It also slips at the beginning of a carrier return operation to
return clutch arbor through a torque limiter (Figure 4). The allow smooth acceleration and prevent an erratic start.
torque limiter is a spring clutch which imparts a controlled
amount of torque to the carrier return clutch arbor.
The torque limiter consists of the torque limiter hub, which Torque Limiter Hub Eccentric Stud
is setscrewed to the operational shaft and the torque limiter
spring. The left end of the torque limiter spring is anchored
to the torque limiter hub by an adjustable clamp. The right
Torque Limiter Spring
half of the torque limiter spring fits over the large shoulder
of the carrier return clutch arbor.
Carrier Return
Latch Actuating
Connecting Link Arm
2. Pawl Clearance —
=— 005"-.015”
(0,13-0,38mm)
Latch Keeper
(Level 1)
b. Level 2 and 3 — Form the tip of the carrier
3. Carrier Return Latch Height — Adjust the carrier
return clutch latch to obtain .005’-.015”
return latch adjusting screw to obtain .0017-.015”
between the escapement pawl and the escape-
clearance between the latch and the cam follower
ment rack during a carrier return and that the
lever. This adjustment should be made to the low side
pawl will be allowed to re-enter the rack
of the spec to ensure a minimum of lost motion.
quickly at the completion of a carrier return
operation. Carrier Return Latch Adjusting Screw
.005"-.015"
(0,13-0,38mm)
Carrier Return Latch
Escapement Pawl ——s .001"-.015””
(0,03-0,38mm)
Clutch Latch
Latch Keeper lb
7X3—7X5
Carrier Return Latch
Adjusting Screw
Level 4 — With the carrier return latched, form
the clutch latch for .010’-.020” escapement
pawl clearance. Ensure that the torque bar latch
is under the lug on the carrier return clutch Carrier Return
latch. Latch \
.0107'-.020” -0017'-.015"
(0,25-0,51mm) (0,03-0,38mm)
8X3—8X5
Carrier Return
Clutch Latch
(Right Side View)
Model 7X1
Latch Arm Adjusting
Screw \e ee Latch Keeper Clutch Latch
3 Coils
(Top View)
.015°-.020': i i,
ri
(0,38-0,51mm)
Cam On High Point
.030'’-.040"
(0,76-1,02mm)
Clutch a gal
Keeper
Carrier Return Shoe
Clutch Latch mal
(Level 2— Right Side View)
(Right Side View)
7. Overbank— 8. Clutch Unlatching —
Level 1 — With the carrier at the left-hand Level 1 — With the power on, hold the clutch
margin, adjust the margin rack eccentric to latch down, The carrier return latch keeper
obtain .001°’-.005” clearance between the left should clear the tip of the carrier return latch
hand margin stop and the carrier stop latch. by .005’’-.015” at the unlatching point.
Next, adjust the bushing at the left-hand end of Lengthen or shorten the carrier return un-
the margin rack to obtain .025”-.030” between latching link to obtain this clearance.
the bushing and the nylon washer.
NOTE: On machines equipped with the early
NOTE: Any change in overbank on machines style margin rack, check the margin rack
equipped with this old-style margin rack eccentric adjustment if the clutch fails to latch
assembly will directly affect the clutch un- properly. The eccentric may be holding the
latching adjustment. rack too far to the left restricting the margin
rack motion and reducing the amount of bite
that the keeper may take on the latch.
GTR Carrier Stop Latch y
.001"’-.005” Clutch Latch Keeper
Clutch Latch
(0,03-0,13mm) ae .005’’-.015""
(0,64-0,76mm)" Margin Rack Margin Rack (0,13-0,64mm)
(Top View)
3
The adjustment of the overbank guide on the = wre .
margin rack determines the rest position of the
margin rack. This adjustment ensures that the
left-hand margin stop will set accurately when
the stop is moved to the right against the car-
rier. The adjustment of the overbank guide,
Torque Bar Latch
= Carrier Return
plus the amount of lateral motion that the
guide permits, automatically provides the : : Clutch;Latch
carrier with the overbank required for proper (Right Side View)
escapement pawl re-entry at the completion of
a carrier return operation. 9. Torque Bar Latch — Form the lug on the torque bar
latch so the carrier return clutch latch will have at
NOTE: Dual pitch machines must be checked bite of .020’-.025” on the carrier return clutch latch
in 12 pitch. keeper when carrier return is latched.
Overbank Guide
Level 1 — Adjust the eccentric stud on the Level 1 — Form the carrier return print inter-
torque limiter hub to provide one to two lock link to satisfy the following conditions.
pounds pull on the carrier as the carrier is With the carrier return clutch latched, the
unlatching the clutch at the left-hand margin. If character interrupter pawl should fully engage
sufficient adjustment is not available at the in front of the cycle clutch link. With the
eccentric, the torque limiter spring may be carrier return mechanism at rest, the interlock
shifted on the torque limiter hub by reposi- link must not restrict the character interrupter
tioning the torque limiter spring clamp. shaft from returning to rest.
Fully Engaged
Character
Interrupter
Torque Limiter Spring
Eccentric Stud
Print Interlock Link
Adjust For |
Positive Carrier ¥/ Character Interrupter
Return Near Shaft
Left Margin
Spring Clamp
(Level 1) (Level 1)
Level 2 — Form the extension lug on the clamp Level 2 — Adjust the clip front-to-rear on the
to provide one to two pounds pull on the carrier return print interlock link to satisfy the
carrier as the carrier unlatches the clutch at the following conditions. With the carrier return
left margin. clutch latched, the character interrupter pawl
should fully engage in front of the cycle clutch
If more adjustment is needed, the clamp can be link. With the carrier return mechanism at rest,
repositioned into another notch. the interlock link must not restrict the char-
acter interrupter shaft from returning to rest.
CAUTION: The spring lug extension may hit
the carrier return shoe arm or the print inter-
lock link when in full overthrow position. Form
the tip of the spring lug down over the loop of
the spring.
Fully
Engaged
Character
Interrupter
Character nterrupter
Inter Shaft
Extension Lug Paw!
(Level 2)
-100-
OPERATIONAL THEORY
Backspace Paw!
Backspace Rack
Adjustable Stud
Carrier
Backspace Latch
Cam Follower
Keylever
Spacebar/Backspace Cam
Interposer
BACKSPACE _ -101-
PAWL OPERATION
The escapement pawl has a small upright stud on its upper
surface which extends through an elongated slot in the
backspace pawl (Figure 2). The stud allows the pawls to
move front-to-rear independently and at the same time it
ensures that they move left-to-right together. By maintain-
ing the lateral relationship of the pawls, the escapement
pawl will cam to the rear and fall into the previous tooth of
the escapement rack as the backspace rack moves the back-
space pawl and carrier to the left.
Upright Lug
Escapement Rack Escapement
Torque Bar
Backspace
Rack
Backspace
Pawl
Escapement
; Pawl
(Rear View)
Backspace Rack
Forces Carrier
Baal To The LeIiu
Escapement Pawl
Mounting
SHU = 22 So eee =
Backspace Pawl
Backspace
Upright Stud Maintains iach
Lateral Position Of
Escapement Pawl Escapement Rack
Backspace Rack
Restores To
The Right Backspace Paw! Moves
To Next Rack Tooth
Backspace Rack
= Escapement
Rack
Lateral Position Of Escapement Pawl
Backspace Paw! Holds Carrier Position
-102-
NOTE: All operational control adjustments must be cor- Level 2 — Form the stop front and rear for a clear-
rect before attempting to make backspace adjustments. ance of .005”-.010” between the vertical lug on the
escapement pawl lever and the backspace pawl when
1. Backspace Latch Height — Adjust the backspace latch the pawl is bottomed in its rack.
adjusting screw for .001’’-.015” clearance between
the latch and the cam follower lever, This adjustment
should be made to the low side of the spec to ensure
a minimum of lost motion.
Backspace Latch
Adjusting Screw
Escapement
Pawl Lever
(fa
Lug Tab Lever
Stop
(Held To Rear)
Backspace
Pawl
Escapement Pawl
Backspace
; Rack
Escapement Rack (Zop View — Level 1)
Tab Lever
Stop
EROS Backspace
.005"-.015" Bellcrank
Screw
(0,13-0,38mm)
Backspace Paw!
.001'"-.003" [:
(0,03-0,08mm)
0, my
(Right Side View) Backspace Rack
7 1 I
f
(Level 1)
Escapement Pawl
Backspace Motion — This adjustment is obtained by
adjusting the intermediate lever front-to-rear. Any
time this adjustment is changed, the backspace rack
adjustment should be checked and readjusted if Backspace Adjusting Screw
Cam On
necessary. Moving the lever to the rear increases back-
High Point
space rack motion. Just Fails To Drop In
Escapement Rack
Intermediate Lever
Escapement Pawl
.005"’-.010" Escapement
(0,13-0,25mm) Rack
Cam On
High Point
Escapement Pawl Just Fails
To Drop In
Intermediate
Lever
Escapement Rack
Escapement Pawl
Escapement Rack
-104-
BACKSPACE OPERATIONAL THEORY
The rotary backspace mechanism pulls the carrier return/ cord. The carrier return/backspace cable is anchored at the
backspace cable to move the carrier to the left one space at carrier to an arm on the cable anchor bracket that is free to
a time. This mechanism functions in either the 10 or 12 pivot. This arm is heavily spring loaded to the right against
pitch mode. a stop lug. The purpose of the pivot arm and spring is to act
as a shock absorber when the carrier is pulled to the left by
Because of this different method of backspacing, the carrier the cable. The other end of the cable is attached to the
transport system in the “Selectric” II] and Correcting carrier return/backspace cable drum. The carrier return/
“Selectric” typewriters is somewhat different than the backspace cable drum and backspace ratchet are one piece
“Selectric”? Typewriter. The major difference in the trans- and operate as a unit (Figure 1).
port system is the use of steel cables that are stretch
resistant and stronger, in place of nylon cords. The tab/
escapement cable/or cord is anchored in approximately the
same manner as the “‘Selectric’”’ Typewriter tab/escapement
Backspace Driver
Backspace Bellcrank
Backspace Ratchet
Mainspring Backplate
Pivot Arm
Stop Lug
Tab/Escapement Cord/Cable
Cord Tension Pulley
Backspace Latch
Tab/Escapement
Backspace Bellcrank
Cord Drum
Mounting Stud
b y,
]
Mainspring Backplate
A\
Backspace
wee Backspace Bellcrank
LEVEL 1
On level 1 machines, the tab/escapement cable drum is
setscrewed to the front of the escapement shaft, but the
carrier return/backspace cable drum is free to rotate on the
escapement shaft independently of the tab/escapement
cable drum (Figure 3). LLLLILLLLLLLLLLLLNLLLLL
LLLLL LLL
A constant pressure is applied to the carrier return/ Backspace Ratchet And Carrier
Driver Links
backspace cable drum through the cable tension arm and Return/Backspace Cable Drum
cable tension spring. The cable tension arm has a ““D”
shaped mounting hole which fits over a flat on the escape-
ment shaft making it a permanent fit to the shaft and turns
with the shaft. The cable tension spring is attached to a lug Figure 4 — Rotary Backspace At Rest (Front View)
on the cable tension arm and a stud on the backspace
ratchet which is permanently attached to the carrier
return/backspace cable drum. This spring keeps the trans-
port cables taut.
Tab/Escapement
Cable Drum
Cable
Tension Arm
Carrier Return/Backspace
Cable Drum Assembly
Tab/Escapement Cable
Pitch Cable
10 Pitch Mode
0 iv
Driver
Backspace
Ratchet ee) |
TILLITLLLLLLLLLLLLIN LLLLLLL
LLL LLLLLLLLIZ a,
Backspace
Driver
Driver Links Ratchet Backspace Latch
Higher Point
Lower Point
Figure 5 — Initial Driver And Bellcrank Motion Figure 7 — Rotary Backspace Switch Pitch Operation
(Front View) (Rear View)
aw Index Transfer
2 Bellcrank
eS
as
Nx Yr 2S |
(Rest Position) j=~ a TK Z
Index Multiplying st Wu
TH) f SS
LT
LEZ. Lever Z <a
Ratchet
-107-
The rearward motion of the backspace latch is used to
ROTARY BACKSPACE ADJUSTMENTS
operate the index interlock. An index interlock link con-
nects the backspace latch to the index interlock bellcrank.
The index interlock bellcrank is setscrewed to the index 1. Mainspring Hub — Adjust the mainspring hub for
interlock shaft which pivots in the switch mounting .001°’-.004” end play of the escapement shaft in the
bracket, The end of the index interlock shaft is positioned rear escapement bearing. This adjustment should be
directly in front of the lower index link. When the back- made with the escapement shaft collar loose.
space latch moves to the rear, the interlock bellcrank moves
the top of the lower index link to the rear of the slot. When
the backspace is operated, the index multiplying lever is
still operated, but the lower index link will move downward
in the slot and the index transfer bellcrank will reamin at
rest (Figure 9).
Escapement Shaft
Switch Mounting Bracket
Index Interlock Bellcrank
(Top View)
Index
Interlock
Shaft 2. Escapement Shaft Collar — Adjust the escapement
(>
shaft collar for .001’’-.004” end play of the carrier
O Lower Index Link return/backspace cable drum on the escapement
shaft.
Index Multiplying Lever
Escapement Shaft Escapement Shaft Collar
Figure 9 — Index Interlock Backspace Operation
(Right Front View) (Level 2)
Carrier Return/Backspace
Cable Drum 001"-.004”
.014"
Escapement Shaft (0,36mm)
Carrier Return/
=
‘Bs:
le oJ
Backspace
NS
Cable Drum
os
Lower Index Link
-108-
3. Transport Cable Tension — Adjust the right-hand 5, Pitch Cam — In the 12 pitch mode, hand cycle the
cable pulley left or right so the cable tension arm backspace until the driver just seats in the ratchet.
clears the stop stud on the backspace ratchet by Adjust the pitch cam cable sheath on the left carriage
.040”-.050.” end plate so the scribe line on the pitch cam lines up
with the center of the stud on top of the backspace
NOTE: If the right-hand cable pulley reaches either driver. Observe this condition through the hole in the
extreme of its adjustment slot, the tab/escapement backplate,
cable drum must be repositioned rotationally on the
Pitch Cam Cable Sheath
escapement shaft. Clamp
Stud
Scribe Line Bs
Wes ¥, as)
Right Hand
Cable Pulley
.040"-.050” ek eS
Stop Stud (1,02-1,27mm) Backspace Driver Mainspring Backplate
(Level 1) (Top View) (Rear View)
Level 2 — On dual transport equipped machines
(nylon tab/escapement cord), adjust the carrier 6. Backspace Motion, Level 1 — Place the machine in
return/backspace cable drum so the nylon pulley the 10 pitch mode and position the carrier approxi-
bracket aligns with the scribe line on the mounting mately in the center of the writing line. Hand cycle 5
bracket. consecutive backspaces. Adjust the nut on top of the
Nylon Tab/ Carrier Return/ backspace latch so that all 5 backspaces travel an
Pull
Escapement Backspace eae a additional .015”-.045” after the escapement pawl
Cord drops into the next rack tooth. This must be checked
Cable Drum
for 5 backspaces because the motion at the carrier
can vary as much as .020.” You may need to
Mounting
manually place the latch beneath the cam follower to
Bracket
check this adjustment.
Escapement Pawl
aw
oo {ot 5”-.045”
(Level 2) (Top View) hea. // (0,38-1,14mm)
1/8''-1 /4"
(3,18-6,35mm)
Cable Sheath
Clamp
Mainspring Backplate
Backspace Latch
“
pressure on top of the carrier.
Backspace
9. Index Interlock Link — Adjust the index interlock
Bellcrank link so the index interlock bellcrank arm is vertical.
Ratchet
|
Index Interlock
Bellcrank
Backspace Latch
Bail
es Mainspring Backplate
.001"-.015”
(0,03-0,38mm)
(Right Side View! (Level 2)
11. Index Interlock Paddle, Level 1 — Loosen the set- 13. Spacebar Link — With the escapement trip link
screw on the index interlock bellcrank. Adjust the properly adjusted, adjust the spacebar link for
paddle front-to-rear for .020”’-.040” clearance to the .001”-.012”’ between the clevis pin and the bottom of
stud on the lower index link. Position the bellcrank the slot in the trigger lever.
left or right to ensure the interlock link does not bind
in the backspace latch or at the clevis. Trigger Lever Slot
.001"-,012”
.020"-.040" . (0,03-0,30mm)
(0,51-1,02mm)
Index Interlock
Paddle
Index Interlock
Bellcrank
(Left Side View)
(Level 1)
14. Backspace Interposer Spring — The backspace inter-
(Right Side View) poser spring must be in the center hole in the
interposer.
Index Interlock
Shaft (Right Side View)
(Level AS
(Right Side View)
Stop Lug
Slot
The half backspace mechanism enables the typist to operate backspace cam when the half backspace lever is operated it
a lever which moves the carrier one half space to the left. pulls up on the operating link, which rotates the cam lever
As long as the half backspace lever is held forward, the forcing it to the left out of its seated position with the half
carrier remains one half space to the left and the typewriter backspace cam. The cam lever then contacts the
will type between the normal escapement positions, This is escapement rack gear, which is setscrewed to the
accomplished by moving the escapement rack one half escapement rack. This camming action moves the escape-
space to the left (Figure 1), ment rack to the left, moving the escapement pawl and
carrier to accomplish a half backspace operation (Figure 1).
The movement of the escapement rack is accomplished by
the half backspace lever, operating link, cam lever and half
Cam Lever
SS
Operating
Link E ie Backspace Cam
<a
Escapement
Rack Gear
Escapement
Rack
SS WS Sie Escapement
GD > Se Pawl
Intermediate
Bellcrank
Half Backspace
Bellcrank
Intermediate Lever
(Rear View)
Escapement Rack
Escapement Rack
Half Backspace Collar
Lug
-114-
3. Half Backspace Rest Position (Level 1) — On 4. Half Backspace Lever (Level 1) — Adjust the upper
machines prior to “A frame” paper feed, disconnect half backspace link so the front edge of the half back-
the lower half backspace link. Hold the rear of the space lever is in line with the rear edge of the platen
half backspace intermediate lever up lightly. Form bearing.
the upper lug on the half backspace intermediate bell-
crank so the pin in the clevis just matches the hole in After the machine is placed in the covers, refine the
the intermediate lever. This ensures that the escape- link so that the lever clears the end of the cover slot
ment rack will rest against the pin in the escapement by about 1/16” when it is in the operated position.
rail when the half backspace mechanism is at rest.
On level 2 machines adjust the operating link to
obtain this condition.
Half Backspace
Intermediate Bellcrank ~~m.
Match Clevis
Pin To Hole (Left Side View)
Intermediate Lever
Hold Up Lightly
1/16 Inch
pet Top Cover
(Rear View)
Half Backspace Rest Position (Level 1) — On level 1 i ee Upper Half Backspace Link
machines equipped with “A frame” paper feed, form
the lower stop lug on the half backspace bellcrank
control bracket so the pin in the clevis just matches
the hole in the intermediate lever.
Lower L
Half Backspace
Intermediate Bellcrank
(Level 1)
Match Clevis 7
Pin-T o-Hole |
Operating Link
(Rear View)
-115-
EXPRESS BACKSPACE OPERATIONAL THEORY EXPRESS BACKSPACE LATCH (SINGLE PITCH ONLY)
On the single pictch “Selectric” 11 Typewriter, there would
be a possibility of the carrier holding on the backspace pawl
The purpose of the express backspace mechanism is to
when the express backspace keybutton is released and the
enable the operator to move the carrier rapidly to the left
carrier stops. Anadditional part, called the express back-
from the keyboard. When the operator depresses the
space latch, prevents this from happening by causing a
express backspace keybutton the carrier will move to the
backspace operation when the EXP keybutton is released.
leff at the same speed as carrier return with the escapement The express backspace latch is mounted on the operational
pawl dragging. The carrier movement stops when the key- keylever pawl guide. When the EXP key is depressed the
button is released or the left margin is reached. * express backspace keylever pawl rotates the express back-
space latch which trips the backspace interposer. At the
The express backspace bellcrank pivots on an extension of
same time another extension of the latch moves behind a
the operational cam check pawl shaft. The express back-
latching surface on the interposer and prevents it from
space shoe is mounted on the left leg of the bellcrank which traveling far enough to the rear to release the operational
is positioned directly under the carrier return clutch spring. cam. When the EXP key is released, it allows the express
When the EXP keybutton is depressed. the keylever pawl backspace latch to restore upward, allowing the interposer
moves downward and pushes on the right leg of the bell to continue to the rear tripping a backspace operation
crank. This causes the left leg to pivot upward and press the (Figure 2).
express backspace shoe against the carrier return clutch
spring. The carrier return clutch spring drives the carrier
return pinion moving the carrier to the left (Figure 1).
Operational Keylever Backspace
Pawl Guide Interposer
K y 2
Carrier Return ) 4
N
Latching Surface
Express Backspace
Express Backspace
Latch
Shoe
cient
(Top View)
Keylever Pawl
.010"’-.020”
Keylever Pawl Guide
(0,25-0,51mm)
Keylever Pawl
.040'-.080”
(1,02-2,03mm) —__ ws |=—
Express Backspace Latch
Backspace Interposer Latch
‘001"2010" =
Express Backspace Shoe (0,03-0,25mm)
Keylever
2/
| Backspace Interposer
.035’’-.050"
(0,89-1,27mm)
-118-
TABULATION OPERATIONAL THEORY
Set/Clear
Arm
Tab Torque
Bar
Tab Rack
Tab Stops
Tab Lever
Set/Clear
Keybutton
Escapement
Set/Clear Escapement
Lever Rack
Backspace
Rack
Carrier
Escapement
Bracket
Operational
Shaft
Tab Governor
Escapement/Tab
Cord
TABULATION § -119-
TAB SET AND CLEAR TAB CLEAR
The tab set/clear button is located at the left side of the The set tab stop may be cleared by depressing the rear of
keyboard (Figure 2). A set & clear link extends towards the the tab set/clear keybutton, thus rotating the tab rack in
rear from the set/clear keybutton and is connected to the the opposite direction (Figure 4). As the tab rack is rotated,
tab set/clear arm. The tab set/clear arm is mounted on a the ‘“‘set’’ tab stop will contact the gang clear finger and be
bracket in such a way that it will toggle front or rear at the rotated within the rack to its “‘cleared”’ position.
top. The tab set/clear bellcrank is mounted on the left end
of the tab rack and its lower projection fits into a notch in Tab stops may be cleared individually or “‘gang cleared.” To
the top of the tab set/clear arm. gang clear, the carrier is positioned to the extreme right of
the writing line, the tab clear keybutton is held depressed,
When the set/clear keybutton is depressed, motion is trans- and a carrier return operation is initiated. The set tab stops
ferred through the set & clear link, the tab set/clear arm, are cammed back to their rest position by the gang clear
and the set/clear bellcrank to rotate the tab rack. finger as the carrier is returned to the left-hand margin.
Gang Clear Cleared
The tab rack is located parallel to and just to the rear of the i Tab Stop
escapement rack (Figure 2). Tab stops operate in slots in the
tab rack with one stop for each escapement position. By
rotating the tab rack, an individual tab stop is forced into
contact with either the escapement bracket projection or
the gang clear bracket. This motion rotates the tab stop
Gang Clear
within the rack to the set or clear position.
Finger
Gang Clear
Escapement Bracket
Projection : Bracket C. Clear Operation D. Clear Position
a
Tab Stop — aa =~ Figure 4 — Tab Clear Operation (Left Side View)
Tab Rack S\) ot TAB ACTUATING
The tab mechanism is activated by depressing the tab
keybutton located at the upper left corner of the keyboard.
.)
o
J As the keylever pivots on its fulcrum rod, the lower exten-
sion of the keylever moves to the rear (Figure 5). This
a
i extension is connected to the tab bellcrank by the tab key-
u
vNet el|| Tab
Bellcrank
Set & Clear ~~
lever link. The tab bellcrank is connected to an arm on the
tab torque bar by the tab torque bar link. The tab torque
Ss bar is mounted parallel to the print shaft at the rear of the
carrier. Depressing the keylever will cause the bottom of
the tab torque bar to pivot to the rear. The torque bar will
a
Brae remain pivoted to the rear until the keylever is released.
TAB SET
As the tab rack is rotated in the set direction (Figure 3), a
tab stop corresponding to the carrier position contacts the
projection on the escapement bracket and the tab stop is
rotated within the tab rack.
Tab Torque
When the tab set button is released, the tab rack restores to Bar
its rest position. The working surface of that tab stop will
now be lower than the other ‘ab stops, or in the “set”
Tab Torque Bar Link
position.
Gang Clear
Set Tab Stop Finger
Gang Clear
-120-
TAB LEVER OPERATION ON EARLY LEVEL MACHINES
Pawl removal is initiated by the torque bar pushing against As the pawls move to the right, they are also moved further
the tab trigger. The lower lug of the tab lever trigger pushes to the rear by the tab lever. The tab lever will continue to
the tab lever to the rear (Figure 6). be moved by the trigger until the trigger is restricted by the
tab overthrow stop. When the keybutton is released, the tab
lever will be held to the rear by the tab lever latch (Figure
Dy,
~~
TAB LATCHING
As soon as the escapement and backspace pawls are re-
moved from their racks, the carrier will be allowed to move Tab Governor
to the right under mainspring tension. Pinion Gear
As the tab lever continues to move to the rear, the tab lever
latch engages a notch in the tab lever to latch the mech- Collars ER Operational
anism in its operated position and to prevent the tab lever Shaft
from overthrowing into the tab rack. With the tab lever Figure 10 — Tab Governor Mechanism
latched, the tab pawl (mounted on the tab lever) is now ina
position to contact the next set tab stop as the carrier During a tab operation, the escapement cord drum rotates
moves to the right (Figure 8). the tab pinion gear in the same direction as the operational
shaft. As soon as the rotational speed of the pinion gear
Set attempts to exceed that of the operational shaft, the clutch
Tab spring tightens around the two hubs locking the pinion gear
Stop and the collar together. Since the collar is setscrewed to the
operational shaft, the speed of the escapement cord drum
will be limited to the speed of the operational shaft.
Tab Latch
CR/Tab Interlock
Backspace
Pawl
Tab Lever
Figure 14 — Carrier Return/Tab Interlock Stop
(Right Front View)
TABULATION ADJUSTMENTS
I. Tab Rack Radially — Push all tab stops to the rear of Tab Lever Pawl — Adjust the tab lever pawl front-to-
their slots. With the tab lever latched to the rear, the rear for .035”’-.045” clearance between the tip of the
top surface of the tab lever pawl should be tab lever pawl at rest and the set tab stops. The
adjustment of the tab lever pawl has an effect on the
.030”-.040” below the lower edge of the tab stop.
amount of overlap between the tab stop and the pawl
Loosen the screw on the tab set and clear bellcrank
tip in the active position.
and rotate the tab rack to make this adjustment.
.035"’-.045”
(0,89-1,14mm)
-123-
4. Pawil Clearance — Form the upright lug on the tab 6. Tab Torque Bar Link — Adjust the tab torque bar
latch for a clearance of .005’’-.015”” between the tip link for a clearance of .001’’-.006”’ between the tab
of the escapement pawl and escapement rack teeth torque bar and the tab lever trigger at rest.
with the tab lever latched to the rear. This adjustment Tabshonane Bar
ensures that the ¢scapement pawl will re-enter the
e<il
rack as quickly as possible to minimize the chances of
Tab Trigger
entering the wrong tooth.
.001’’-.006”
(0,03-0,15mm)
Escapement
Bracket
Tab Torque Bar Link
Escapement \
Pawl
(Rear View)
Tab T P 005”-.015”
ote 8 gE |e eae)
Escapement AES.
Rack Th
ANY
.005"-.015” is
(0,13-038mm) Overthrow Stop
(Latched Position)
Tab Keylever
&. Tab Rack Left-to-Right — Adjust the tab rack left-to-
right for .005’’-.020”’ clearance between the tip of the
tab lever pawl and the left side of a set tab stop.
Tab Rack
.005"’-.020"
Tab Bellcrank
Rear Arm
-124-
9. Tab Interlock — With the carrier return clutch
latched, the escapement torque bar should rotate the
tab latch away from the tab lever by .005”’-.025.”
CR Latch Keeper
.005"'-.025"
Level 2
(0,13-0,64mm)
Il. Tab Set Lug — Form the stop lug on the tab set and
clear bracket so that when a tab stop is set, the tab
lever pawl will contact the center of a set tab stop
ne(0) Ose
Tab Latch
If the tab stops, located on either side of the tab stop
that is being set, contact the underside of the tab
Escapement
Torque Bar
clear bracket before the proper set position is ob-
tained, the tab set finger at the rear of the escape-
ment bracket should be formed down.
(Left Rear View)
-010'’-.020”
Bang Clear Bracket
a\"ages
CR Latch Keeper
oo .010"-.020"
Upper Lug (0,25-0,51mm)
Level 1
-125-
13. Tab Clear Lug — With the tab stops at the rear of
their slots, form the stop lug so that the gang clear
bracket will clear the upper lug on the tab stop by
.001’’-.010” when the tab clear is operated.
ae Guceeeal
0) aaa
IN Clear Bracket
Tab Stop At
Rear Of Slot
14. Tab Set And Clear Link — Adjust the tab set and
clear link so the tab set and clear keybutton matches
the slope of the keyboard.
Match Slope Of
The Keyboard
.002’’-.004”
(0,05-0,10mm)
Backlash
Collar
(Top View)
-126-
TCH TABULATION OPERATIONAL THEORY
The dual pitch tab mechanism can operate in either 10 or 2. Before switching pitch, all tab stops should be cleared
12 pitch without any mechanical switching. This is and necessary tab stops reset after the pitch is
accomplished by a universal tab rack. The tab stops are changed.
spaced in such a way that the escapement pawl will reenter
the proper rack tooth correctly in either pitch (Figure 1).
Dual pitch tab provides the operator with the same features
as single pitch tab, but with two additional instructions:
Set/Clear
Arm ete
Tab Torque
Bar
Tab Rack
Escapement
Bracket
Tab Lever
Set/Clear
Keybutton
—7---=,
=>"
aes
Set/Clear
Lever
Escapement
Rack
Carrier
Operational
Shaft
Tab Governor
Escapement/T
ab
Cord
Tab Stops
Tab Lever
TAB ACTUATING
The tab torque bar is pivoted to the rear in the same
manner as a single pitch ‘‘Selectric’’ Typewriter. The tab
torque bar contacts the tab lever trigger, moving it to the
rear. The tab lever trigger lug contacts the upper lug on the
tab lever. As the tab lever moves to the rear, its lower lug (Right Front View)
contacts the escapement pawl, removing it from the
escapement rack (Figure 3). Figure 5 — Tab Lever Pawl Mounting
Tab Lever Trigger
ee Upper Lug
When the tab lever is latched out, the escapement pawl is
Tab Lever removed from the escapement rack and the carrier moves to
OQ
the right. The tab lever pawl contacts a set tab stop, causing
Bar the tab lever to stop as the carrier continues to move to the
right. After .020” of additional movement of the carrier,
the escapement pawl drops from the lower lug on the tab
Lower Lug A Escapement Pawl lever and, under its spring tension, restores back into the
escapement rack. Further movement of the carrier causes
Escapement the tab lever to unlatch and restore to its rest position. The
Rack escapement pawl against the escapement rack tooth stops
the carrier (Figure 6).
Figure 3 — Tab Actuating And Escpament Pawl Removal Tab Lever Pawl
Tab Lever Set Tab Stop
The tab lever is latched by the latch lug of the tab latch
rotating into the latching notch. The rear edge of the notch
acts as a latching surface for the tab lever. The front of the
notch contacts the latch lug and acts as an overthrow stop
for the tab lever. The interlock lug on the tab latch rests
behind the escapement torque bar and will cause the tab to
be unlatched any time the escapement torque bar is
operated (Figure 4).
Tab Latch
-128-
UNIVERSAL TAB STOP SPACING
The tab stops are spaced on the universal tab rack to DUAL PITCH TAB ADJUSTMENTS
‘accommodate both 10 and 12 pitch escapement racks.
Figure 7 shows the tab lever pawl contacting a tab stop, if it
1. Tab Rack Radially — Position all the tab stops to the
were set, and approximately where the escapement pawl
rear of their slots. Latch out the tab lever. Adjust the
starts to enter the escapement rack tooth for that stop.
tab rack radially within the tab set and clear bellcrank
Every 1/2 inch (5 teeth in 10 pitch and 6 teeth in 12 pitch)
for .030’’-.040” between the tab stops and the tab
an escapement rack tooth is common for both pitches;
lever pawl.
therefore, the tab stop spacing is repeated every 1/2 inch
_ (Figure 7).
Tab Rack
Escapement Pawl ih ay
bate |
! 10 Pitch
la &|£| 4 || Escapement
j 0 arack Teeth
SS,
ji fs EN NS es
(Left Side View)
12 Pitch
Tooth KI2/A|G) 44) Escapement
\ ewexivle Rack Teeth 2. Tab Lever Stop — Form the tab lever stop on the
escapement bracket so the lower tab lever lug clears
the escapement pawl by .010’’-.015”’ at rest.
(010".015” Escapement Pawl
Escapement
Figure 7 — Universal Tab Stop Spacing (0,25-0,38mm) Bracket
|
—
(0,76-1,02mm)
|
t
! 2
-129-
4. Tab Latch Bite — With the tab lever latched out, 7. Tab Torque Bar Link (Level 1) — Adjust the torque
adjust the escapement pawl guide bracket bar link so the tab torque bar rest position is vertical.
front-to-rear so the left edge of the tab latch lug
clears the bottom of the latching slot in the tab lever
QI Torque Bar
by .001°-.010”’.
ot} 1 Vertical
Tab Lever Escapement Paw!
Guide Bracket Sra
Z
Torque
1001: O10 ae
Bar Link
(0,03-0,25mm)
(Top View) Tab Torque Bar Link (Level 2) — Disconnect the tab
keylever link. Adjust the tab torque bar link so the
torque bar arm clears the tab rack compression spring
5. Escapement Pawl Clearance — With the tab lever by .001”’-.030” at rest.
Torque Bar Arm
latched out, form the tab latch lug so the escapement
pawl clears the escapement rack by .005”-.010”’. ae Se
Tab Lever Escapement Pawl
Compression .001°’-.030"
Spring (0,03-0,76mm)
ao}
Torque Bar 0
Keylever Link
(Top View)
Tab Lever 9. Tab Trigger — Form the front lug on the tab trigger
so it clears the tab torque bar by .001”’-.005”’.
Ore
t '
.005"’-.010"
Tab Latch (0,13-0,25mm) .001**-.005”’ |
(0,03-0,13mm)
-130-
10. Tab Keylever Down Stop — With the tab keylever 12. Tab Interlock — With the carrier return clutch
bottomed, adjust the tab keylever down stop so there latched, the escapement torque bar should rotate the
is .005"-.010” clearance between the tab latch lug tab latch away from the tab lever by .005”’-.025.”
and the rear surface of the tab lever latching notch.
This adjustment is obtained by forming the lug on the
tab latch that extends down behind the escapement
torque bar. The adjustment ensures that the carrier
return and tab cannot both be latched out simultane-
ously. If both were allowed to latch, the tab lever
pawl would lock against a set tab stop during the
carrier return operation.
.005”-.025’"__,] |
Tab Latch
(0,13-0,64mm)
Interlock Lug
Keylever
Down Stop 005’'-.010"
(Level 1) (0,13-0,25mm) Tab Lever
Tab Latch
Tab Lever
aay: i” Latching Notch
Latching Notch
(Top View)
13. Carrier Return/Tab Interlock — Form the lug of the
On level 2 machines with the tab keylever bottomed, interlock to obtain the following conditions:
adjust the tab keylever link to obtain .005’-.010”
clearance between the tab latch lug and the rear a. With the carrier return mechanism latched, the
surface of the tab lever latching notch. interlock should pull the carrier return latch
keeper forward just enough to release the latch
when the tab lever is fully depressed.
C/R Tab
Interlock
Tab Rack
A i
Tab Lever Pawl
-131-
14. Tab Set And Clear Bracket — Adjust the tab set and 15. Tab Set Stop Lug — Form the set stop lug on the tab
clear bracket for the following conditions: set and clear arm bracket so the tab lever pawl
engages the center of a tab stop when set.
a. Adjust the .tab set and clear bracket
front-to-rear for .010”-.020” clearance between Tab Stop Tab Lever Pawl
the contour of the clear finger and the contour
of the tab rack. Adjust left-to-right so that the
set finger will reliably set and clear each tab
stop individually when the machine is in the 12
pitch mode and will set and clear the two stops
that are spaced close together simultaneously
when the machine is in the 10 pitch mode.
Paw! Engages Center
Of Set Stop
.010°'-.020"
(0,25-0,51mm) Tab Stop
(Match Contours) Tab Rack Set Stop L
Desig Set And Clear Arm
(Left Side View)
Two Closely Spaced Stops (Left Side View)
16. Tab Clear Lug — With the tab stops positioned at the
extreme rear of their slots, form the clear stop lug of
the tab set and clear arm bracket so the tab stops are
.001’-.010” from the tab clear finger when the tab
set and clear arm is against the lug. This ensures
minimum noise during gang clear.
ura
12 Pitch 10 Pitch i
ie sae
Clear
.005"-.015"
(0,13-0,38mm)
paca
(Left Side View)
-132-
PRINT GPERATIONAL THEORY
The purpose of the print mechanism is to power the There are two basic conditions necessary for a correct print
typehead toward the platen. This is accomplished through a operation. They are: correct velocity of the typehead as it
print cam located in the carrier assembly (Figure 1), When strikes the paper and proper platen position.
the printer is cycled for a character selection/print
operation, motion is transferred by the print shaft through Two levels of velocity may be selected on machines having
the print cam, a cam follower and the rocker assembly to the dual velocity feature. Alphanumeric characters receive
power the typehead toward the platen. the highest velocity while smaller characters such as
punctuation and symbols receive a lower velocity.
Copy Control
Lever
Platen
Typehead
Impression
Control Lever
Ss Eg
~ Le Rocker
Print Cam
NS
Print Cam
Follower
Carrier Assembly ||
Low Velocity
(
fi YS Ky
Key lever =e
Low Velocity
Cam Follower
Low Velocity (
Vane
Low Velocity
Latch
PRINT = -133
FRONT CARRIER SUPPORT PRINT OPERATION
The typehead is supported in front of the paper by a frame Drive to operate the print cam mechanism is supplied
called the carrier (Figure 2). Its purpose is to transport the through the print shaft (Figure 3). The print shaft extends
typehead and related mechanism along the writing line. The the width of the frame and is supported in a bearing at each
carrier assembly is supported in front by the print shaft and end. A gear at the left end of the print shaft meshes with an
a print sleeve. The print sleeve is keyed to the print shaft idler gear of the character selection mechanism. When the
and therefore turns whenever the print shaft is rotated. character selection mechanism is cycled, motion is trans-
Motion for a print operation is taken off the print sleeve. ferred through the idler gear and the print shaft gear to
rotate the print shaft top-to-rear. The print shaft is rotated
Due to print shaft flex, the front of the carrier needs addi- 360 degrees each cycle.
tional support. An anvil is located under the front of the
carrier (Figure 2). On level 2 (XX3 and XX5) machines, a The print cam is setscrewed to the print sleeve, which in
carrier pad contacts this anvil when flexing of the print turn is keyed to the print shaft. bi
shaft occurs. On level 1 machines, a buffer screw and a
buffer plate serve the same function. (Rear carrier support When the print shaft is rotated, motion is transferred
is covered in the Fine Alignment Section of this manual.) through the print sleeve to rotate the print cam. Print cam
motion is then’ transferred through the cam follower and
the impression control lever to pivot the rocker assembly
Print Shaft about the rocker shaft and power the typehead toward the
platen.
Print Sleeve
Anvil Bearing Rocker
Carrier
NIgf
Pad f
Print Shaft
Rocker Pivot
(Level 2) Shaft
Print Shaft
Escapement Rack
Print Cam
/ 5
Carrier / Print Cam
Follower Roller
o%
(Level 2)
XC a
YY s hi Ci Print
Casting — : X \|/ 4a lf Shaft
Print
Print Cam Cam
Buffer Screw or Buffer Follower
Anvil Plate
(Level 1)
(Level 1)
Figure 3 — Print Operation
-134-
IMPRESSION CONTROL LEVER (LEVEL 2) PRINT MECHANISM (LEVEL 1)
The impression made by the typehead is determined by the Level 1 machines did not have the automatic velocity
velocity of the typehead upon impact with the paper. By control mechanism. The impression was a preset adjustment
increasing or decreasing the velocity of the typehead with and could not be changed by the operator (Figure 5).
the impression control lever, the impression for all
characters can be changed equally. The print cam is a double cam. Its function is to power the
typehead toward the platen and restore it to rest. A small
The impression control lever may be positioned by the camming surface on the right is the print cam and moves
operator to one of five different impression settings (Figure the typehead toward the platen. A larger camming surface
4). Changing the position of the impression control lever on the left is called the restoring cam. It restores the
causes a pin in the lower part of the lever to move to the typehead to rest and prevents it from rebounding.
front or to the rear of the print cam follower arm. The
front-to-rear position of the pin determines the amount of The camming surface of the print cam is designed so the
powered travel the typehead receives from the print cam typehead is powered within a few thousandths of an inch of
follower. This, plus the amount of free flight, determines the platen. Because the typehead is powered nearly all the
the velocity of the typehead upon impact with the paper. way to the platen, all the characters are forced to emboss
the paper slightly, even those with a large surface area, To
Powered flight is the distance the typehead is driven by the restrict the amount of free flight of the typehead so
print cam. Free flight is the amount of typehead movement embossing will be the same for all characters, a heavy arm
from the high point of the print cam to the platen. called the anvil striker is attached to the bottom of the
carrier and acts as a stop for the rocker. Just under the
front of the carrier and extending between the side frames
is an anvil. It is an angle-shaped bar with the lip extending
to the rear. As the typehead embosses the paper to the
Detent Plate correct depth, the striker hits the bottom of the anvil and
prevents further travel of the rocker and typehead. This
means that the impression for each character will be
Impression consistent with little variation between characters.
Control Lever
Platen
Typehead ;
Plate
Print Cam
Print Cam
Follower
er
= Pinin Sh Shown
Chee In Medium
Position
Striker ‘\ Print Cam
Print Cam Follower
Stop Screw
Restoring
Anvil can
Figure 4 — Impression Control Lever
(Level 2) (Right Side View)
Figure 5 — Print Mechanism (Level 1)
135
PLATEN
The quality of typed impression is determined to a large
extent by the condition of the platen. Platen rubber may be
adversely affected by numerous factors such as light, heat,
chemicals, etc. An old or worn platen may also vary slightly
in diameter.
Carriage
Guide Bracket
Carriage
Platen
End Plate
Adjusting Eccentric
Plate Collar
Shaft
-136-
DUAL VELOCITY SELECTION If a high velocity character is selected at the keyboard, the
On machines with dual velocity, when a low velocity low velocity latch will remain at rest in the operating path
character is selected, a pull on the velocity control cable is of the stop on the cam follower. The cam follower is
produced to shift the roller to the low velocity lobe on the restricted from following the contour of the cam and no
print cam (Figure 7). A low velocity vane is mounted in the pull is felt on the velocity control cable. The print cam
keyboard in a position to be contacted by the selector follower roller remains to the right under the high velocity
interposer as it is driven forward by the filter shaft. lobe of the print cam and a high velocity print operation
Attached to the right end of the low velocity vane is the results.
low velocity vane bellcrank. Rotation of the vane and
bellcrank creates a pull on the link, causing the low velocity
latch to rotate counterclockwise about its mounting stud.
Low Velocity
As the latch rotates, it pivots out of the operating path of
the adjustable stop attached to the low velocity cam Low Velocity Cam
Cam Follower
follower. The low velocity cam follower is spring loaded
against the low velocity cam. With the low velocity latch
Velocity
removed from its operating path, the cam follower will Latch Restoring
Control
travel to the low dwell of the low velocity cam and create a Spring
Cable
pull on the velocity control cable.
Low Velocity
Latch 5
Adjustable
Stop
Low Velocity
Selector Cam
Interposer
7 Low Velocity
Cam Follower
Low Velocity
Vane |
Sa Velocity Control Cable
Adjustable
Stop
Low Velocity
Latch
Low Velocity
Vane Bellcrank
-137-
This is accomplished by using a print cam that has two PRINT CAM FOLLOWER STOP SCREW
different camming surfaces (Figure 8). The low and high On the level 2 print mechanism, the print cam follower and
points of both camming surfaces are identical. The only roller are held disengaged from the print cam by an
difference is in the contour between their low and high adjustable stop screw until the roller has shifted (Figure 9).
points. The contour of one camming surface has a more This prevents the print cam from interfering with the print
gradual rise and provides the typehead with a lower impact cam roller as it shifts from one lobe to the other.
velocity than the other. The difference in typehead
velocities produced by the two camming surfaces remains
proportional between all settings of the impression control Impression
lever. Control Lever
Print yd Velocity
1. Copy Control Lever — With the multiple copy lever
Cam eae detented in the forward position, the high point of
Y Ana eR ~
the eccentric should be up. Loosen the multiple copy
f Print Cam
lever setscrews and rotate the shaft to satisfy this
Low Follower condition. The stop ears on the copy control detent
Velocity a spring should be formed to provide positive detenting
Lobe in the extreme front and rear positions of the lever.
Copy Control
Eccentric
Touching Vertical
Platen
Touching With
Multiple Copy
Platen Latch
Control In Pos.
ba
.030"
(0,76mm)
-139-
NOTE: Adjustments 5 through 8 are for level 1 machines 6. Anvil (Level 1) — Adjust the eccentric at each end of
only. the anvil to properly restrict the free flight of the
typehead. With one sheet of paper installed in the
5. Velocity Control Plate (Level 1) — The velocity machine, the period should just fail to print with the
control plate must be adjusted to satisfy the copy lever all the way back. With the copy lever
following two conditions. pulled forward one notch (second position), the
period should print lightly.
a. With the cam follower held lightly against the
low point of the print cam, the center of the NOTE: The restoring cam follower eccentric should
home character should clear the platen by be adjusted all the way up while the anvil is being set.
.260”’-.270”’. On 7X5 machines, the carrier buffers must also be
moved up out of the way of the anvil.
NOTE: The adjustments should be checked
with the ribbon removed. The .260”’-.270” can
be gauged with two or three tab cards plus the
No Period Copy Lever — 1
foot of the Hooverometer handle. Light Period Or Copy Lever — 2
Tab Cards
Eccentric
yh Platen
7X1 (7X3-7X5)
Restoring Cam
Eccentric Up
Follower Eccentric
Before Making |
Adjustment
Y
°2607--270e
(6,61-6,86mm) Print €am
(Hooverometer Follower
Velocity + 2 Or 3 Tab Cards)
Control Plate
(Right Side View)
(Right Side View)
Eccentric Up
Before Making
Adjustment
Slight Drag eae
On 3 Tab Cards
re Anvil Tay i
(7X3-7X5 ) (7X3-7X5) |
.002"'-.004"" .002"-.004"
(0,05-0,10mm) (0,05-0,10mm)
140-
8. Print Cam Follower (Level 1) — The print cam 9. Yoke — Position the yoke rotationally under its
follower must be adjusted to satisfy the following mounting screws so the density of the left and right
conditions: sides of a printed character is uniform.
a. Print Cam Follower Stud — Adjust the pivot This adjustment will affect the tilt ring homing
stud left-to-right so the rubber roller on the adjustment, the typehead homing adjustment and
follower is centered on the surface of the skirt clearance. Be sure to check these adjustments
restoring cam. The stud is held in place in the after changing the position of the yoke.
carrier casting by a setscrew that is accessible
from the bottom of the machine.
Restoring
Roller
became
(Front View)
(Top View)
10. Carrier Shoe — Adjust the level 1 carrier shoe
eccentric mounting stud to obtain .001’-.004”
vertical play between the carrier shoes and the
b. Restoring Cam Follower Eccentric — With the escapement rack. The level 2 carriers equipped with
print cam follower at the high point of the cam the spring loaded carrier shoe should be adjusted for
and the platen removed, hold the typehead .001”-.005” of vertical movement with the spring
toward the rear until it is restricted by the anvil pressure removed. This adjustment should be checked
and striker. The roller should just touch the at several points along the escapement rack.
restoring cam. Adjust the eccentric, keeping the
Eccentric
high point forward, to satisfy this condition.
Mounting Stud
Escapement
NOTE: If the roller is too close to the restoring Rack
cam, it may bind against the cam during print
shaft rotation. If too much clearance exists, the
typehead may not be restored as quickly as is
necessary and blurred characters may result. .001°"’-.004”
(0,03-0,10mm) Carrier Shoe
(Level 1 — Rear View)
Restoring Cam
Follower Eccentric Escapement
Typehead
Touching
.0017*-.005"
(0,03-0,13mm)
Carrier Shoe With Spring
Pressure Removed
(Level 2 — Rear View)
Level 3 Parallel — Loosen mounting screw on carrier
Print Cam
Follower
shoe. Press down firmly on rear of carrier, keeping
carrier shoe parallel with escapement rack, tighten
screw.
Aivil Striker Mounting , —_ \ Escapement Rack
Screw //
Touching
|[eee
MMU UL aes Por |||/ —
se Oy t
Grease 1st — Low Dwell
Track
@
= | sn @ Point “"A”’
Roller Track
Carrier Pad Should Begin
.001""-.004"” Here
Carrier Support (0,03-0,10mm)
. .020"
Print Cam Follower
(0,51mm) .000"'-.010" ——+»}|——
Machine Stop Screw
(0,00-0,25mm)
At Rest
(Right Side View)
This adjustment may be checked by applying a light
film of grease on the print cam and then observing
the track that the roller makes in the grease when the
machine is hand cycled. If the stop screw has been
adjusted properly, the roller track in the grease
should begin at point “‘A”’ on the print cam. This is
just before the beginning of the rise on the print cam.
-142-
14. Carrier Cable Deflector — Form the deflector to the 16. Velocity Control Keyboard Cable Clamp — Adjust
rear as far as possible without touching the power the cable sheath front-to-rear under the clamp so the
frame. print cam follower roller will shift onto the low
velocity lobe of the print cam by the width of the
roller plus .030’-.040” when a low velocity character
is half cycled. Moving the cable sheath to the rear will
produce more motion to the roller.
-030"-.040”
Print Cam Follower Roller (0,76-1,02mm)
Print Cam
Cable Deflector
Carrier Cable
Power Frame
Carrier 2
Spaces From
Left Limit
Low Velocity
Vane Low Velocity
Latch
Carrier Low Velocity Cam
Side Frame
-143-
18. Low Velocity Cam — When a low velocity character is 20. Powered Flight — With the machine latched at rest
slowly hand cycled, the low velocity latch should and the impression control lever set at position 4,
clear the adjusting stop on the cam follower by loosen the binding screw and move the detent plate
.008”-.01 2” just as the cam follower scribe mark lines front-to-rear until a clearance of .250” is obtained
up with the second scribe mark on the low velocity between the center of the letter ‘‘z” and the platen.
cam. Advance or retard the cam to satisfy this The foot of the Hooverometer may be used to
condition. measure the clearance.
CAUTION: The copy control lever must be
This adjustment can easily be made in the following positioned all the way forward when making
manner: adjustment No. 20 and No. 21.
19. Low Velocity Cam Follower Stop — With the cycle Platen
shaft latched at rest, adjust the low velocity cam
follower stop for .008”-.012” clearance with the low Impression Control Lever
velocity latch. Loosen the binding screw and rotate
the low velocity cam follower stop to satisfy this
condition.
Binding Screw
o
(0,89mm)
Low Velocity
Latch
.008"-.012”
Print Cam
(0,20-0,30mm) >,
ate Cycle Shaft Latched Impression Control
Low Velocity Cam Lever Eccentric
Follower Stop
(Right Side View)
(Right Side View)
-144-
PAPER FEED AND INDEX OPERATIONAL THEORY
The purpose of the paper feed and index mechanism is to The feed rolls mount in the front and rear feed roll arm
hold the paper firmly against the platen so that it will move assemblies. Each feed roll arm assembly pivots on a pivot
with the platen as it is indexed vertically. stud at the rear of the “‘A frame.” Heavy extension springs,
connected between the “A frame” and feed roll arm
The paper feed mechanism uses an “A frame” for support assemblies, supply constant tension on the feed rolls. There
and contains all the parts necessary to control paper feed. are several notches cut into the feed roll arm assemblies to
provide a means of adjusting the feed roll pressure.
The paper is held against the platen by the front and rear
feed roll assemblies located beneath the platen. Each feed
roll assembly contains three or four rubber rollers equally
spaced along the feed roll shaft and molded to the shaft.
Platen
Ratchet
Paper Bail
Lever
Index
Selector
Lever
\ Page End
Indicator
|
Paper
Release
Lever
Extension
Deflector
Feed Rolls °
Cardholder K
He
Feed Roll S 3
Arm SS
SS ae
pe J
Cam Follower
The cardholder assists in holding the typing material against The paper bail is supported by a lever at each end and
the platen in the printing area. A scale on each side of the pivots front-to-rear. A hairpin spring attached to each bail
cardholder aids the typist in reinserting material into the lever serves as a toggle to hold the bail rolls either to the
machine to a specific printing point. The vertical marks on rear against the platen or forward in the release position.
the scale indicate the middle of the character space and
Center
Paper Guide
Bail Roller Cover
Paper
Paper Bail
Lever * Platen
Deflector
aN
“\ IS
Hairpin
Spring
Carrier
Feed Rolls
-146-
PAPER RELEASE INDEX MECHANISM
The pressure of the feed rolls can be released from the The index mechanism operates to line space the paper
platen to allow the operator to position the paper more vertically. An index operation can be obtained by
accurately and to allow easier insertion and removal of the depressing either the carrier return keylever or the index
paper (Figure 4). Paper release is accomplished by pulling keylever. Depressing the carrier return keylever also causes
forward on the paper release lever located at the right end the carrier to move to the left margin, whereas depressing
of the machine. The front of the paper release lever cams the index keylever causes only an index operation. The
the feed roll release arm forward to rotate the feed roll index selector lever may be positioned so the mechanism
actuating shaft. The feed roll release levers are clamped to will line space either one or two lines during each
the feed roll actuating shaft and has a lug resting on each operation. With the lever in the forward position, single line
feed roll tension arm. As the shaft rotates, the feed roll spacing will occur. The mechanism will double line space if
release levers rotate the feed roll tension arms, moving the the lever is to the rear. Indexing is achieved by a pawl
feed rolls away from the platen. When the paper release which engages and rotates a ratchet on the right end of the
lever has been pulled all the way forward, the end of the platen (Figure 6). The ratchet is locked to the platen so the
feed roll release arm detents to hold the feed roll release platen will rotate also.
lever in the released position.
Motion to operate the index mechanism is supplied through
Feed Roll the carrier return/index cam. Motion is then transferred
Release Lever through the cam follower.
Detents
Feed Roll
Actuating Shaft
Feed Roll Here Index
Release Arm
Paw!
Figure 4 — Paper Release Mechanism Carrier Selector
Cam
(Released Position) Platen
Ratchet
MACHINES EQUIPPED WITH TIE ROD SUPPORT Index
Paper release is accomplished by pulling forward on the Selector
paper release lever located at the right end of the machine Platen
Lever
(Figure 5). The front of the paper release lever cams the
feed roll release arm forward to rotate the feed roll
actuating shaft. The feed roll release levers are clamped to
the feed roll actuating shaft and rest behind a lug on each
Platen wii A
feed roll tension arm. As the shaft rotates, the feed ,roll Ratchet Detent
release levers rotate the feed roll tension arms and the front
feed roll arms down, away from the platen. Due to the
interconnection between the front feed roll arm and the
rear feed roll arm, the rear feed roll arms are forced away
from the platen. When the paper release lever has been
pulled all the way forward, the end of the feed roll release Cam Follower
arm detents to hold the feed roll release lever in the
released position.
Feed Roll
Tension Arm
Feed Roll
Release Lever
Multiplying
Paper Release Lever Sto
Lever Carrier Return Pp
Index Cam Multiplying
,ih, Was Lethe
Dy Detent Index Lever
~
“SI
-
Ge -
U7
y> 3 a
Index Selector
Lever
Index Pawl
ae
nee Selector Platen
Hairpin ee Ratchet
Spring \ |
Mounting
Platen
Stud Platen
Detent Elongated Overthrow Stop
Roller
Hole Index Pawl
Selector
= 0 = . Overthrow Stop
Index Bracket
Index Pawl
148.
PLATEN VARIABLE The left side of the platen ratchet contains two pins that fit
The platen variable mechanism provides the operator with a into holes in the platen driver. The platen driver operates
means of rotating the platen to a position other than the left-to-right and always turns with the ratchet. A
normal writing line (Figure 11). The platen variable is used compression spring between the ratchet and the driver loads
for typing permanently above or below the writing line or the driver to the left so the serrations on the outer surface
locating the writing line after reinserting the paper. The of the driver mesh with matching serrations inside the
platen ratchet must remain stationary when selecting a new platen end plug. The meshing of the serrations causes the
writing line so that the detent roller will be seated between platen, the driver and the ratchet to be locked together and
the two teeth of the ratchet at the new position. A clutch turn as a unit.
mechanism connects the ratchet to the platen so that it can
be engaged for line spacing and disengaged by pushing the
left-hand platen knob toward the right. As long as the PAGE END INDICATOR
platen knob is held to the right, the platen can be rotated The page end indicator (Figure 11) located on the
freely while the ratchet remains stationary. When the knob right-hand platen knob allows the operator to judge the
is released, the clutch is automatically reengaged by spring typed distance down the page. It is calibrated in half inches.
tension, The operator must align the top edge of the paper with the
writing line on the cardholder. For a standard size sheet of
When the driver is disengaged from the platen end plug, the paper, the operator must rotate the indicator until position
platen can be turned to the desired position. The driver can 2 is in line with the horizontal mark on the top of the
then engage different serrations and lock the platen in the typewriter adjacent to the right platen knob. When using
new position. The left-hand platen knob is mounted to a other than standard 11” paper, the operator may locate the
shaft that slides left-to-right inside the platen. A light indicator setting from the page indicator chart in her
compression spring holds the shaft toward the right to operator manual.
prevent free play. The shaft pushes against the platen
driver. Movement of the platen knob toward the right is
transferred to the driver to disengage it from the platen end
plug.
Compression Spring
Platen (‘Selectric 2)
Driver (Serrations)
3G(Sy
.
Compression
Spring
Ratchet
Line Position
Platen Ratchet
(@%
i Feed Roll Tension (“A Frame’’) — Place the feed roll
Platen tension springs in the notch that will provide 2-2-1/2
pounds tension when measured at the front feed roll
pivots.
Shaft
Control
ox.GS =
Tension Spring
Center Support
Bracket Front Feed .010"-.015”
Roll =a =. (0;25-0:'38mm)
-150-
4. Feed Roll Arms (Level 1 & 2) — 5. Paper Release — Adjust the feed roll release levers
front-to-rear to obtain .055’’-.065” clearance between
a Adjust the feed roll arms to obtain .008”’-.012” the rear feed rollers and the platen when the feed
clearance between the front feed rolls and the rollers are released.
platen when three tab cards are inserted
between the rear feed rolls and the platen. Excessive clearance can cause interference between
the front feed roll and the carrier, whereas
3 IBM Cards insufficient clearance will not permit straightening of
thick paper packs.
055""-,065" ye
(1,40-1,65mm) —”
Platen
y.
.008"'-.012"’
RS] ; (0,20-0,30mm)
Deflector
Cardholder
Xx oe 5"
(0,13-0,38mm)
.002"-.005"
(0,05-0,13mm)
.020"’
(0,51mm)
-152-
10. Switch Bracket — Adjust the switch bracket left or right 13. Index Selector Cam 27-Tooth Ratchet ~ With the
to ensure that the lower index link does not bind in the index lever in the double space position, press down
slot in the index transfer bellcrank. on the index link until the index pawl is just
bottomed in a ratchet tooth. Adjust the index
selector cam so a clearance of .010’-.040” can be
observed between the working surface of the selector
cam and the rear tip of the index pawl.
Slot
With the index lever in the single space position,
adjust the selector cam vertically so the index pawl is
Lower Index Link centered on the cam surface.
oe males
Index Selector Cam Index Pawl
Cam At Rest
Hooverometer
Single Space Position
Index Link
Ss ndex Pawl
Paw! Centered
12. Index Transfer Bellcrank Stop Lug (Rotary Index Selector Cam 54-Tooth Ratchet — With the
Backspace Only) — Form the index transfer bellcrank index lever in double space, press down on the index
stop lug for a .001”-.010” clearance between the stud link until the index pawl is just bottomed in a ratchet
on the lower index link and the lower horizontal edge tooth. Adjust the index selector cam so a clearance of
of the slot in the index transfer bellcrank. This will .005”-.030” can be observed between the working
ensure that the lower index link stud reliably restores surface of the selector cam and the rear tip of the
to the front of the slot after a backspace operation. index pawl.
.001""-.010" Sid
(0,03-0,25mm)
Index Transfer
Bellcrank .005"’-.030”
(0,13-0,76mm)
Slot
Just Bottomed
(Right Side View)
(Left Side View)
14. Index Link — As a preliminary step, loosen the platen NOTE: The following adjustments are for early level
overthrow stop and move it to the front of the machines only.
machine. With the platen installed and the feed rolls
engaged, hold the detent roller disengaged from the 16. Index Link And Index Stud (Level 1) — As a
platen ratchet. Manually cycle a double line space preliminary setting, position the index link stud in
operation. At the end of the cycle, allow the detent the middle of the slot in the pawl carrier. Subsequent
roller to reenter the platen ratchet. If the index link is adjustments may require that the position be altered
properly adjusted, the detent roller will seat between slightly. With the index selection lever in the single
the two ratchet teeth without causing any rotational line space position and the carrier return/index cam
movement to the platen. Adjust the index link clevis latched at rest, insert four tab cards between the
to obtain this condition. carrier return cam and the cam follower. Adjust the
index link so the index pawl isbottomed in the
ratchet against the tooth.
Ratchet Adjust For 2T
Motion Of Platen With the carrier return index cam on the high point,
adjust the index stud front-to-rear to obtain one full
tooth of motion from the index pawl after it starts to
Overthrow Stop drive the platen. The upper index pawl stop must
allow the index pawl to bottom in the ratchet.
Just In
A Tooth
Index Pawl
(0,13mm)
Adjust For 1T
Motion Of Platen
al
(Right Side View) (Right Side View)
-154-
17. Upper Index Pawl Stop (Level 1) — With the index 19. Platen Overthrow Stop (Level 1) — Adjust the platen
cam latched at rest, adjust the upper index pawl stop overthrow stop front-to-rear to obtain a clearance of
to obtain .015”-.030” clearance between the index .005” between the index pawl and the platen
pawl and the platen ratchet. overthrow stop with the index cam rotated to its high
point,
Ratchet
Upper Index Paw! Stop
Overthrow Index Paw
Stop
.015"'-.030"
(0,38-0,76mm)
Index Pawl
(Left Side View)
Index Pawl
Overthrow Stop
@ Multiplying Lever
RIBBON TAKE-UP The ribbon lift Mechanism consists of a ribbon lift cam, a
Once the ribbon leaves the feed roller, the used ribbon is
cam follower, a control mechanism, and the ribbon lift
wound onto the transparent take-up spool. The take-up
guide assembly. The lift mechanism is mounted to the
spool receives its motion from the feed mechanism by a
carrier and moves with it. The ribbon lift cam is a single
friction type spring drive system (Figure 5).
lobe cam that is setscrewed to the left-hand side of the
print sleeve. Each time a print cycle occurs the cam makes
A drive pulley located directly below the feed roller rotates
one complete revolution (Figure 7).
with the feed roller during a ribbon feed operation. This
drive pulley supplies the motion to the take-up pulley The ribbon lift cam follower pivots on the carrier assembly
through a drive spring. The take-up pulley, driven by the above and to the rear of the cam, Each revolution of the
drive spring, rotates about the take-up spool pivot stud and cam raises the cam follower. The end of the ribbon lift
is held in place by a ‘“‘C” clip. The shape of the belt groove control link fits into an elongated slot in the cam follower.
in the take-up pulley is designed slightly different from that The ribbon lift guide rests on the control link and pivots at
of the drive pulley. This is to permit all of the necessary the front of the carrier casting. As the cam follower is
slippage of the drive spring to occur at the take-up pulley raised, the control link forces the ribbon lift guide assembly
and not at the drive pulley. This slippage is necessary to to pivot at the front and raise the rear of the assembly. A
ensure the take-up spool will wind all of the ribbon. Two flat link from each side of the ribbon lift guide attaches to
hooked lugs on the top face of the take-up pulley project two pins at the front of the carrier to maintain the ribbon
into corresponding slots in the bottom of the transparent lift guide in a vertical position (Figure 7).
take-up spool. These lugs provide a locking connection
between the take-up pulley and the disposable take-up
spool. Cam Follower a 2
Pivot Lift Guides
Supply Shock Drive
Spool Spring Pulley
Ue aimas
= ‘GS; Take-Up Spool Lift Cam
Supply Spool FA ys < Pivot Stud Follower
Detent oo
/ q :
ed
Ne ”
Lift . \
Control 3 Ne Guide
Link ‘y eg rms
Ribbon Feed e Flat Link
Roller oR me
Drive Hooked Ribboniluinicamt | Lift Guide Pivots
Spring Lugs
Figure 7 — Ribbon Lift Mechanism
Figure 5 — Take-Up Spool Drive
-158-
The four lift positions obtained by moving the control link Lift Control Link ir ieee Gtr ee
are designated by “A”, “B”, “C” and “‘D” (Figure 8A),
Positions “A” and “C”’ are low lift positions while “B” and bet ae Guide Assembly
“Dp” are high lift positions, These four lift positions occur i!
Cam Follower AS
Lift Cam
ye
Medium High
Detent
Medium Low
Lift C
Lift Control Lift Control
: Feed Windows Link Lever
High Lift D
-159-
STENCIL CONTROL RIBBON LOAD
Whenever the machine is used for typing stencils, the rib- When the operator desires to change the ribbon, she begins
bon feed and lift operation must be locked out. This is by pushing the load lever to the rear into its load position.
accomplished by pushing the stencil lever, located on the This causes the ribbon lift guide assembly to rise above the
front on the carrier, to the rear (Figure 10). typehead so the ribbon may be easily threaded through the
guides. Latching the load lever in its load position causes
The lockout of the feed mechanism is achieved through a the lower extension of the load lever to contact an exten-
lug on the stencil lever. In the stencil position, the lug sion on the lift guide assembly and cam it upward. At the
pivots to the right into the path of the upright lug of the same-time, an extension on the pressure roller lever is con-
feed pawl. Ribbon feed is interrupted because the feed pawl tacted by the upper portion of the load lever and pivots the
is not allowed to move to the rear and drop into the next pressure roller away from the feed roller, The operator may
feed window. now install a ribbon with no obstructions (Figure 11).
"Extension
Lu
Pressure s
Roller Ri
Stencil ibbon Load
Extension
Lever Lever
Stencil Lever Figure 11 — Ribbon Load Position
Lift Control Lug
Lever
Feed NOTE: Lower extension of right-hand ribbon plate mount-
Pawl Window
ing screw is used to lock load lever latched in load position.
Shock Spring
Feed Plate
Supply Spool
-160-
RIBBON FEED STENCIL LOCKOUT
During a feed operation the supply spool brake is mechani- In the stencil position, the feed pawl shield is rotated
cally disengaged by the ribbon lift mechanism (Figure 13). beneath the feed pawl to prevent the feed pawl from oper-
The upper extension of the lift guide plate contacts the ating in the feed windows (Figure 15), Lockout of the lift
brake actuating lever when the lift guide is in the raised mechanism is achieved in the same manner as the present
position, As the brake actuating lever pivots about its pivot mechanism, However, the parts design is slightly different.
point, it cams the supply spool brake out of engagement
with the supply spool.
Feed Pawl
Cam Follower
Control Link
Lift Control
Lever
RIBBON LOAD
Figure 13 — Ribbon Shock Spring And The ribbon load operation is initiated by a ribbon load bail
(Figure 16). A link is connected between the ribbon load
Brake Actuating Lever (Level 1)
bail and the load lever. The load lever raises the lift guide
assembly in the same manner as the current load lever.
Detent Spring
Link
Figure 14 — Feed & Lift Wheel Detent Spring (Level 1) Figure 16 — Ribbon Load Operation (Level 1)
-161-
An adjustable pressure roller release arm is attached to the By Ribbon Feed Cam Follower Bracket — With the
load lever to release the pressure roller in the load position nylon carrier pad against the carrier casting, the rib-
(Figure 17). The pressure roller release arm pushes against bon feed cam follower bracket should be centered
the pressure roller lever, As the pressure roller lever pivots left to right in its mounting hole. Keep the bottom of
away from the feed roller, it also cams the supply drag lever the bracket parallel to the carrier pad.
away from the supply spool. Thus, all obstructions are
removed to permit the operator to install a new ribbon,
Ribbon Feed
Cam Follower
Bracket
{ Rear View)
Load Lever
Centered
Ribbon Plate
Dimple
Slot
-162-
4 Ribbon Feed Cam Follower Stud (Level 2) — Hand Sp Ribbon Feed and Lift Wheel Detent Spring (Level ]
cycle the machine and observe the lift control lever Only) — Hand cycle the machine and observe the
stud as it moves from the low point to the high point ribbon feed and lift wheel detent spring as the ribbon
on the ribbon feed and lift wheel. Adjust the ribbon lift control lever roller moves from the low point to
feed cam follower eccentric stud so the ribbon lift the high point on the ribbon feed and lift wheel. The
control lever stud overthrows the detent notch in the ribbon feed and lift wheel should travel .015” after
ribbon feed and lift wheel by .005”’-.015,” the detent spring drops into a feed window.
015”
SUD (038mm)| he
| &
ELS
.005"-.015” oD
(0,13-0,38mm) New wy
Beyond Detent Position As RQ fayov 6. Brake Actuating Lever (Level 1 Machines Only) —
Cam On High Point \ ac Form the lug on the brake actuating lever so the
supply spool brake is allowed to just bottom in the
hae
ratchet teeth of the supply spool when the machine is
e Ribbon Feed and Lift Wheel at rest.
aN
WA
J) Supply Spool Brake
Ribbon Feed
Paw! yf Ribbon Lift
& / Control Lever
: / . Roller
a 1/16 Turn =
1 Feed Operation
Ze Z ae
=i
~
))
| D Load Lever Link (Level 1 Only) — Adjust the load
lever link to raise the ribbon lift guide assembly as
Ly en
high as possible without binding off on either the
ribbon feed plate or the take-up spool when the load
bail is in the load position.
Ribbon Lift = Ee) 7
Control Link Ribbon Lift Guide Assembly
(Right Side View) Lift Guide Assembly
HHHHHH
HHHHHH
LIFT GUIDE PLATE
OUT OF PARALLEL
TOO HIGH AT THE
OUT OF PARALLEL
(J TOO HIGH AT THE
FRONT
Q
LIFT GUIDE PLATE
PARALLEL TO SLOT
IN CAM FOLLOWER
(Load Position)
10. Pressure Roller Release Arm (Level 1) — Adjust the 12. Shock Spring (Level 1) — Position the shock spring so
pressure roller release arm beneath its binding screw, it is approximately .040” to the right and parallel to
located on the left end of the load lever, so the the edge of the ribbon feed plate. The shock spring
supply drag lever will be pushed forward by the should be formed to make the roller on the shock
pressure roller to just clear the front edge of the spring lean 10 deg, to the left.
supply spool.
Clears
a Las 10 Deg.
A : 7
040" © el Pa le
Pressure Roller (102mm) Ve — WANT
Supply Spool fi |n |
“|
alp
Load Lever
Pressure Roller f y R }
| Ee ja 2S
Release Arm
(Level 1)
13. Drag Lever (Level 1) — The supply spool drag lever
must contact the outer wrap of the ribbon on the
supply spool at the center or slightly above. Form the
lever to obtain this condition. Do not form it front to
Il. Supply Spool Drag Spring (Level 1) — Adjust the rear.
supply spool drag spring to satisfy the following con-
ditions: NOTE: After forming the lever make sure that it
does not bind on its pivot screw. If the supply spool
a. Position the drag spring parallel to the front drag lever contacts the ribbon below center, the outer
edge of the ribbon feed plate. wraps of the ribbon spool will tend to creep up which
may cause ribbon spillage.
b. With the “C” clip removed, the drag spring
should raise the supply spool so half of the
angled surface on top of the pivot stud is pro-
truding above the top face of the spool. Form
the drag spring up or down to obtain this con-
dition.
Pr ts Supply Spool
Parallel
abet
| 1/2 Angled
Supply Spool Drag Spring Surface Drag Lever
Centered Or
Above
-165-
14, Tracking Post (Level 1) — Position the tracking post 16. Pressure Roller (Level 2 Only) — Machines with the
under its mounting screw so it clears the flanges of adjustable geared pressure roller should be adjusted so
the transparent take-up spool by .030.” Form the the lower end of the pivot screw clears the take-up
tracking post atthe bottom so the tracking post is drive pulley by .065.”
vertical to the feed plate. If the tracking post is verti-
cal, the ribbon will be centered as it passes between
the two flanges of the transparent take-up spool. It Pivot Screw
should also track on the center of the feed roller and
Pressure Roller
evenly between the two flanges of the tracking post
without touching either flange.
.065""
(1,65mm)
Take-Up Spool
‘all
Take-Up Drive Pulley
Center
Ribbon
Tracking Post
Vertical
Shock Spring
fina 5
(Level 1 — Front View)
(Front View)
Parallel
Centered ;
10 Deg. —> |
quam
Shock Spring
Roller
Pressure Roller Feed Roller
-166-
RIBBON OPERATIONAL THEORY
The fabric ribbon mechanism can be divided into two Located to the right of the pointer on the carrier assembly
separate mechanisms. They are the ribbon lift mechanism is the ribbon load lever. When this lever is pushed to the
and the ribbon feed mechanism. The ribbon lift raises the right, it forces the ribbon lift guide into an extreme lift
ribbon to the printing position before the typehead prints position for convenience of changing the ribbon. This load
and then restores the ribbon to allow a visible writing line. lever is detented to hold the ribbon lift in the high lift
The ribbon feed moves the ribbon laterally past the printing position. The cartridge is then removed from the ribbon
point to provide an unused portion for the next typing feed plate and the ribbon can be easily removed from the
operation. Included in the ribbon feed mechanism is the guide without touching the ribbon.
ribbon reversing mechanism which changes the feeding
direction when either end of the ribbon is reached. A new ribbon can be installed by reversing the above
procedure. Tapered lugs on the sides of the ribbon feed
The ribbon is a 9/16” fabric ribbon enclosed in a disposable ratchets automatically guide the ribbon spools into the
cartridge unit for clean handling. The cartridge unit correct position. Guide lugs at each side of the feed plate
contains two spools on which the ribbon is wound. The maintain the lateral position of the cartridge. Retainer
ribbon is constantly fed from one spool to the other and springs attached to the guide lugs hold the cartridge down
back again. Once the ink supply has been depleted, the to prevent vibration. After the ribbon is installed, the load
cartridge is simply snapped off, discarded and a new lever is moved back to the left to allow the ribbon to
cartridge is installed (Figure 1). restore to its normal position for a typing operation.
Ribbon Lift
Guide Assembly
Ee Lug
Retaining
Ribbon Feed
Plate
Cartridge
Pointer
Ribbon Load
Lever
Ratchet
Detent Release
FABRIC RIBBON
RIBBON LIFT The fabric ribbon mechanism has four lift positions. A lift
The ribbon lift mechanism consists of a lift cam, a ribbon position is selected by manually positioning the ribbon lift
lift cam follower, a control mechanism and the ribbon lift lever for stencil, low, medium or high lift position. The
guide assembly (Figure 2). The lift mechanism is mounted height to which the ribbon will be raised is determined by
to the carrier and moves with it. The ribbon lift cam is a the position of the ribbon lift control link in the elongated
single lobe cam that is setscrewed to the left side of the slot of the cam follower. When the control link is to the
print sleeve. Each time a print cycle occurs, the cam makes rear of the slot, no motion is transferred to the lift guide
one complete revolution. assembly. When the control link is to the front of the slot,
maximum motion is imparted to the lift guide assembly
The ribbon lift cam follower pivots on the carrier assembly (Figure 3).
above and to the rear of the cam. Each revolution of the
cam raises the cam follower. The end of the ribbon lift
Ribbon
control link fits into an elongated slot in the cam follower.
The ribbon lift guide rests on the control link and pivots at
LOW MEDIUM HIGH ____
the front of the carrier casting. As the cam follower is
raised, the control link forces the ribbon lift guide assembly
to pivot at the front and raise the rear of the assembly. A
flat link from each side of the ribbon lift guide attaches to
~_Lift Guide
two pins at the front of the carrier to maintain the ribbon
Assembly
lift guide in a vertical position.
Ribbon Lift
Control Link : ;
The ribbon lift guide assembly is spring loaded into the rest Medium Low Stencil }
position to ensure that it will restore rapidly and to prevent Lift
overthrow of the ribbon due to the momentum of the lift
mechanism (Figure 2).
Ribbon Lift
Ribbon Lift Cam "&) Cam Follower
/
spool will also move. Two flat retainer springs are mounted
iG
on the ribbon feed plate at the rear so that they rest against }
the ribbon feed ratchets. The slight drag applied by the Ps. Reverse Trigger
Feed Plate_ j ai :|
springs prevents the jerk of the ribbon feed operation from =<3 Spring
spinning the supply spool and spilling off excessive ribbon —_——,
Feed Pawl
Lug Engages
Retainer Spring
Ribbon Feed
Ratchet
_s
Ribbon Feed
Ratchet
Stud
“S
ddl ax
pi cole dae
| (e€
Uy
Ratchet Teeth
Ribbon Feed
, Hairpin Spring
Feed Pawl
Ratchet Detent Clears Both
Lever Stud Ratchets
Ribbon Feed
Detent Lever
: : Lug To Left Restoring |
Lever Sprig Ribbon Feed
Ribbon Feed Cam Follower
Figure 9 — Ratchet Detent Centered i Bellerank
Reverse
Trigger . ; Zi, Ratchet
Ribbon Reverse ( /
Restoring oa I nterposer - \
Ribbon Feed
Spring 7% Cam Follower
Flat Link
Print Slot
Sleeve -005"’-.010"
Ribbon Feed Plate (0,13-0,25mm)
Centering Springs
4. Cartridge Guide Lugs— Form the cartridge guide lugs
Ribbon Feed Plate
so the cartridge spools will be centered over the
ratchets. Side play of the cartridge must be limited
within .005”-.010”.
Ribbon Reverse
Interposer
.005"-.010”
—_ (0,13-0,25mm) Ar cee
.003"'-.005” .003"-.005"’
(0,08-0,13mm) (0,08-0,13mm)
(Top View)
(Front View)
-172-
Cartridge Retaining Springs (Level 2 Only) — The b. Form the rear lug so a clearance of .010’-.040”
cartridge retaining springs should be positioned exists between the lug and feed plate
laterally so they are FLUSH against the feed plate; positioning lug when the LEFT RATCHET IS
then adjust front-to-rear so the cartridge retaining FEEDING.
fingers are centered in the holes of the cartridge guide
lugs. The ratchet brake portion of the spring should
exert a small drag on the feed ratchet. Form only as
necessary.
in reverse failure.
Flush
tf vf
SS
/
Centered
1a
A Feed Plate
ate: i
Positioning
il Lug
'
HT
in
Uh
)
1!
i!
it
:
UJ
Feed Plate
Positioning Lug
Stencil Position
Ribbon
Lift Lever
-173-
Ratchet Detent Lever Lugs — These should be formed Ribbon Lift Control Link — Adjust the link forward
as follows: or back by means of its clevis so the underscore will
strike the ribbon .016”-.045” from the bottom edge.
ae Left or right so the ribbon feed ratchet tooth The ribbon lift lever must be in the high lift position
overthrows the edge of the detented lug by when this check is made.
.025”-.050” when hand cycling to the high
point of the ribbon feed cam. CAUTION: Do not adjust the link so short that it
chokes off the front end of the cam follower slot as
the ribbon lift lever is moved into the high lift
.016"'-.045"
Feed Cam On (0,41-1,14mm)
High Point
Minimum Engagement
Ribbon Feed Latch
.030” (0,76mm) ——$<$ ||< ——_
Z Parallel
Ribbon Lift Carn eS (Right Side View)
-174-
SELECTIVE RIBBON OPERATIONAL THEORY
The purpose of the selective ribbon system is to operate The feed modes for the IBM Correctable Film Ribbon and
with the film ribbon, the IBM Tech III ribbon or the IBM film ribbon are the same, but the feed mode for the IBM
Correctable Film Ribbon. All three of these ribbons are Tech III ribbon differs completely. The film ribbons must
contained in a cartridge, similar in appearance to the be fed so that no characters overlap, whereas the IBM Tech
‘Selectric’? Typewriter fabric ribbon cartridge, but Ill ribbon is fed in much smaller increments so as to use the
considerably larger. The complete supply of ribbon is in the overstrike capabilities of this ribbon. The inner
left side of the cartridge. The used ribbon will be wound construction of the cartridge determines in which ribbon
around the take-up core on the right side and the cartridge feed mode the mechanism will operate.
will be discarded when the ribbon is used up. The cartridges
for the three types of ribbons look the same but have A ribbon lift pattern of three tracks is used for all three of
different color take-up knobs and leaders for identification; the ribbons. However, the IBM Tech III ribbon lift is
blue for IBM Tech III, cerise (pink) for film and yellow for wobbled (varied) slightly to maintain even color.
the IBM Correctable Film Ribbon (Figure 1).
Ribbon Leader
Take-Up Knob
Take-Up Core
Stencil Lever
Spiked Driver
Ribbon Lift
Guides
Supply Spool
End Of
Ribbon
Take-Up Post
INNA
SS i Ribbon Plate
Feed Windows
N Feed Cam
Figure 4 — Ribbon Feed, Print Cycle Near Completion
(Right Rear View)
Ribbon Plate
Bearing
Feed Pawl
Feed And Lift Wheel
Feed Cam Follower
Feed Window
Hex-Headed Screw
The rotation of the ribbon feed and lift wheel rotates the
ribbon feed post. The ribbon feed gear, mounted on flat
surfaces of the feed post, also rotates (Figure 6).
Feed Cam
The spiked driver is mounted on a post at the free end of
the swing arm. Two intermediate gears mounted on the
swing arm transfer the feed gear rotation to the spiked
Figure 3 — Ribbon Feed, Early Stages Of Print Cycle driver.
-176-
Intermediate Gears IBM TECH IIT RIBBON MODE
Ribbon Feed Post
In the IBM Tech III ribbon mode, a projection within the
Spiked Driver
cartridge depresses the ribbon mode button which, through
a compression spring, depresses and holds down the ribbon
feed gear. This allows the small gear on the ribbon feed gear
to engage the large gear of the first intermediate gear and
causes the spiked driver to rotate approximately 1/6 the
amount as in the film ribbon mode (Figure 9).
BCE ors
Cie Ch
Medium
/ 1 as
Lift
High Lift Lift Cam le}
Follower YG 5
Ribbon Spread ™ Low Lift
Adjusting Plate
Lift Cam Lift Cam
Follower Pivot
LLLLLLNNNNNN
é 3 | ate @ Cam
Ribbon Lift Pattern LLLLLLNNNNNN Ribbon Lift (OQ 8 "034SS,——Follower
LLLLLLNNNNNN & FeedWheel go> {Roller
Bh 7
= UAE:rrsy wi
q SD
s
have the ability to move vertically in curved slots in the lift OW, Ribbon Lift Cam
guide brackets. The lift guides are connected to the lift
arms by the lift guide links which are part of the lift guide Ribbon Lift Control Ribbon Lift Control Lever
assemblies. The lift arms are biased (loaded) together by the Lever Stud
lift guide bias springs to prevent erratic ribbon lift (Figure Figure 13 — Ribbon Lift Operation
12).
In the IBM Tech III ribbon mode, the ribbon lift pattern is
‘“‘wobbled” or varied slightly to ensure even print color.
Lift Guide Bracket —___, /
This is accomplished by the wobbler cam, the wobbler
bellcrank and the wobbler eccentric. The left pivot point of
Lift Guide Link
the ribbon lift arm assembly is the wobbler eccentric. The
wobbler eccentric has an upright lug that extends above the
Lift Arm Lift Guide Bias surface of the ribbon plate. Moving this lug front-to-rear
Spring causes the wobbler eccentric to rotate, moving the left lift
arm pivot point up or down (Figure 14).
-178-
Wobbler Eccentric Lift Arm Pivot
Pivot Point cH Point Wobbler Bellcrank ie (277
@
Control Lugs |
\ Ribbon
Feed Gear
b= Ribbon
At Feed Gear ;
Wobbler Bellcrank oe Stencil Lever Latch Feed Lockout Lug
Control Lugs rh Wobbler Cam
at —— Latching Surface
=a
Wobbler >
__ 9 JEL
a Wobbler Eccentric i am Followe
e Ribbon Plate sich bilan seie ea
Bellcrank Sai tePor ey Roller
wa
2, wy
NA ; D e OSes Gear
WaBEleeotht ee \\a! Feed & Lift Release Button \
Ce ae A — Wheel i Feed Pawl
<7 2 ae
IF. Stencil Lever Mounting Stud
Lift Cam
-179-
RIBBON LOAD
When the ribbon needs to be changed, the load lever is SELECTIVE RIBBON ADJUSTMENTS
moved to the left to the load position. An inclined surface
on the load lever contacts a lug on the right front of the lift 1, Ribbon Feed Cam Follower Bracket — Adjust the
arm assembly. This cams the front of the lift arm down and ribbon feed cam follower bracket left or right so the
raises the lift guides for easier ribbon installation (Figure ribbon feed pawl is .001’-.010” from the wobbler
18). cam at the closest point, with the play in the ribbon
feed pawl held away from the wobbler cam.
During the loading of a ribbon, the operator must be
prevented from turning the take-up core in the wrong This adjustment will ensure that the feed pawl will
direction. The take-up core interlock extends to the left not bind against the wobbler cam and will not move
from the right cartridge retaining spring. In the load beyond the outside limits of the feed window.
position, the take-up core interlock engages the teeth on
the take-up core, preventing it from -being rotated in a The bracket screws can be made accessible from
clockwise direction. In the normal operating position, the underneath by removing one of the cable anchor
take-up core interlock is held away from the take-up core bracket screws and pivoting the cable anchor out of
by a lug on the load lever. the way.
The load lever latch will not allow the load lever to restore
to the operate position until a cartridge is installed. This
Wobbler Cam
depresses the latch and allows the load lever to be restored |
to the operate position.
{+———Ribbon Lift
em ene .001'’-.010"
Guide (0,03-0,25mm)
Play Removed In
Load Lever This Direction
Latch Lug
eS Sel
Ribbor i / fi
\ eee
# p c Core
Lift Arm ft \ Interlock Lug
Inclined Surface ra
Weir: Take-
ake-Up Core Interlock Bracket Screws
(Rear View)
figure 18 — Load Lever Operation
As the swing arm moves to the load position, it contacts the
wobbler bellcrank, rotating it clockwise. This positions the
wobbler beilcrank so that when it restores, it will reliably 2. Ribbon Lift Arm — Adjust the right-hand lift arr
latch against the ribbon plate in the film ribbon mode or pivot screw for .005”-.010”’ end play of the lift arn
easily move down into the operated position in the IBM Make this adjustment with the wobbler eccentric lv
Tech EI ribbon mode (Figure 19). in an upright position.
ay Wobbler Bellcrank
Shock Wire =
.005"-.010"
Camming as (0,13-0,25mm)
Surface Ny
(Top View)
Shock Wire Detent Supply Spool
005”.
Hooverometer
.005’’-.010" |
(0,13-0,25mm)
Ribbon Feed And Lift Wheel
(Top View)
Ribbon Lift
Cam Follower
Roller
-181-
7. Ribbon Spread Adjusting Plate — In the film ribbon 8. Ribbon Lift Height — In the film ribbon mode, adjust
mode, adjust the ribbon spread adjusting plate the ribbon height adjusting screw so the bottom edge
front-to-rear to obtain .380”-.410” from the bottom of the underscore clears the bottom of the ribbon by
of a high lift character to the bottom of a low lift .030’-.040”. Ribbon spread must be checked after
character. This may be measured with the aid of the making this adjustment.
Hooverometer handle which is .375” wide. The
ribbon spread adjusting plate must be biased in a
clockwise direction as viewed from the left side of the
carrier when tightening the binding screws. This is
easily accomplished by tightening the screws with the
machine half cycled. This takes out the play in the
en |
mounting holes in the direction of the lifting force
and ensures that the adjustment does not change. .030’'-.040”
Ribbon height must be checked after making this
adjustment. a8 Ribbon Height
Adjusting Screw
—_{0,76-1,02mm)
FA
B)
seal
.380"-.410"
(Left Side View)
9 65-10,41mm HHHHHHHHHHHHH
HHHHHHHHHHHHH HHHHHHHHHHHHH
HHHHHHHHHHHHH HHHHHHHHHHHHH
HHHHHHHHHHHHH
\
Xe
.005"’-.025" Lo
(0,13-0,64mm)
omni Lower Stop
-182-
10. Ribbon Shock Wire — Form the shock wire to be tm |!«_ Clearance Between Roller
vertical front-to-rear and left-to-right. This & C-Clip
adjustment may need to be refined for proper ribbon Ribbon Lift Cam Follower Roller Ribbon Feed
tracking through the left ribbon lift guide. Lockout Lug
Pees:
Vertical Vertical
Ribbon Lift Cam
Ribbon Lift
Control Lever
Stencil Lug
(Top View)
11. Stencil Adjustment — Form the stencil lug on the
ribbon lift control lever to meet two conditions when
the stencil lever is latched in the stencil position. 12. Swing Arm Lug — Form the lug on the swing arm
that contacts the wobbler bellcrank so the cam
a. The ribbon feed lockout lug must engage the follower stud on the wobbler bellcrank clears the high
ribbon feed pawl mounting stud by lobe of the wobbler cam by .030’-.040” when the
approximately the thickness of the lockout lug. load lever is detented in the load position.
Swing Arm Lug
Ribbon Lift Cam Follower Roller
Ribbon Feed Lockout Lug
Wobbler Bellcrank
Ribbon Lift
Control Lever Highest Lobe
Stencil Lug
Ribbon Feed
Paw! Mounting 030"-.040"" Wobbler Cam
Stud (0,76-1,02mm) ————»> <x
(Top View)
b. The ribbon lift cam follower roller must be Shock Wire Disengage L ever '
moved to the right, completely off the ribbon Load Position
lift cam, but still have some clearance between
the roller and the C-clip at the end of its shaft.
1 +)
2~
NOTE: During normal typing, in the low lift ribbon ss,
position, the ribbon feed lockout lug on the ribbon
lift control lever must clear the ribbon feed pawl
mounting stud. If necessary, form the ribbon feed
lockout lug to obtain this condition. If the lug is
formed, recheck the stencil adjustments. Shock Wire \
Dete nt
(Top View)
-183-
14. Shock Wire Disengage Lever (Type Position) — In the 17. Take-up Core Interlock — Form the take-up core
IBM Tech III. ribbon mode, form the shock wire interlock so that in the load position, the tip of the
disengage lever rest position lug so the shock wire interlock is .025’-.040” above the top edge of the
disengage lever arm clears the wobbler eccentric by middle step on the take-up post.
.005°-.015” when the wobbler bellcrank is on the
high point of the wobbler cam.
Shock Wire Disengage Lever
.025"'-.040"
(Operation Position) Take-Up Post (0,64-1,02mm)
.005"’-.015"
(0,13-0,38mm)
ih
EN CS
KD
Wobbler Bellcrank : ~
U B | .
Wobbler Cam vu ar
High Lobe
Take-Up Core Interlock
15. Cartridge Guides — Form the cartridge guides to 18. Load Lever — Form the take-up core interlock lug on
center the ribbon take-up and supply cores within the the load lever to meet two conditions.
holes in the top of the cartridge. Maintain
.005”-.010” end play of the cartridge. a. In the operate position, it must hold the
take-up core interlock down completely
Supply Core Take-Up Core disengaged from the take-up core.
a Center
pe b. When going from load to operate, the tip of the
lug must clear the top surface of the take-up
¢ Go &
( ie
core interlock by a sufficient amount to
reliably depress it.
Take-Up Core
+! 005"-..010" 2
4 (0,13-0,25mm GR RE Completely Disengaged 7a an
epee (fa IU
Take-Up Core
16. Cartridge Retaining Springs — Center the cartridge Interlock
retaining springs in the holes in the cartridge guide
lugs. Adjust the springs left-to-right so they positively
hold the IBM Tech III ribbon cartridge down against
the ribbon feed plate. Refine the right spring
‘rotationally so the take-up core interlock clears the
middle surface of the take-up post by .005”-.020”’.
Load Lever
Take-Up Post
(Top View)
-184-
CORRECTING’ OPERATIONAL THEORY
The purpose of the correcting mechanism is to enable an Each of the correcting tapes is designed to be used with a
operator to correct original copy errors from the keyboard. specific IBM ribbon. The IBM Tech III Cover-up Tape is
A correcting tape supply spool is mounted at the left rear used with the IBM Tech III Ribbon (both are color coded
corner of the ribbon plate and a tape take-up spool is blue). The Lift-off Tape is used with the IBM Correctable
mounted at the right rear corner of the ribbon plate (Figure Film Ribbon (both are color coded yellow). Due to incom-
1). The correcting tape is guided from the tape supply spool patability, intermixing of supplies is not recommended.
on the left, across the front of the cardholder, to the tape
take-up spool on the right.
Card Holder
Tape
Supply Spool
Correcting Tape
Tape
Take-up
Spool
Escapement
Torque Bar
Escapement
Trigger
&
Su
Torque Bar YA
Stop Bracket Le
Carrier Ss : G wv——___ Mode Actuating
SY
Belicrank
Correcting
Torque Bar
Backspace
Keylever we
Correcting
Key
Tape Lift
Actuating Arm
(Operated) Correcting
Torque
R Bar
Front /
Carrier Support Figure 3 — Lift Armand Latch (Left Side View)
When the print sleeve rotates, the tape lift cam raises the
Correcting Mode Uatch tape lift cam follower which in turn raises the lift arm and
Torque Bar
latch assembly (Figure 4). As the lift arm and latch assem-
bly is raised, an extension on the rear of it will raise the
tape lift assembly. An arm on the tape lift assembly engages
the tape supply cradle fork on the tape supply cradle assem-
bly. As the tape lift assembly raises, the cradle assembly is
tilted to maintain tape alignment and prevent folding of the
correcting tape.
Lift Arm and T,
Latch Assembly ae ae
AS
ESL
Tape Supply Tape Lift Assembly
Cradle
Assembly ~
Backspace
Keylever
Tape Lift
Cam.
Actuating CET - Correcting Keylever
Print Sleeve
Lug Link
Correcting
Keylever
Follower
-186-
CORRECTING TAPE FEED The tape feed cam then rotates to its first high point. The
The correcting tape feed mechanism is located on the right tape feed pawl by means of the cam follower, feed bell-
side of the carrier (Figure 5). It is designed so that the crank and link rotates the spiked wheel clockwise for the
correcting tape is fed in two increments. One-third is fed first one-third tape feed (Figure 7). The feed cam then
before print and two-thirds is fed after print. This is accom- rotates to a low dwell position again. The follower is pre-
plished by a tape feed cam with two high points, the second vented from contacting the cam on its low dwell by the
high point supplying twice as much motion as the first. inhibitor. The inhibitor prevents placing the heavy cam fol-
lower spring load on the cam during print which occurs at
this time. The cam then begins its rise to the second high
Carrier guar Lug, point and the cam follower causes the correcting tape to be
fed the remaining two-thirds of the tape feed increment.
First High
Point
DP Tape Feed
co
Correcting Inhibitor
Tape Cam Follower
Tape Feed
Figure 5 — Tape Feed at Rest
Cam
Tape Feed
Cam Follower Rear Lug
eae
ie 7c
Step
~~
\Spiked Whee!
en
Tape
Feed Pawi
Correcting
Torque Bar
Bellcrank
-187-
TAPE BIAS SYSTEM ESCAPEMENT TRIGGER OPERATION
The correcting tape supply cradle assembly contains a bias The escapement trigger is disengaged from the escapement
system that performs three functions. First, the detent on torque bar to prevent escapement during a correcting cycle.
the high bias spring prevents the supply spool from being Disengagement of the trigger is accomplished from the
rotated clockwise (Figure 8). mode actuating bellcrank through the trigger link (Figure
10). As the bellcrank rotates to its activated position, the
Second, a low bias is supplied for use with the IBM Tech III escapement trigger is rotated top to the rear out of engage-
Cover-up Tape. This bias is produced by a low bias spring. ment with the torque bar. It is held in this disengaged
As tape is being pulled off the supply spool and the tape position by the spring tension on the mode actuating bell-
supply spool ratchet turns counterclockwise, the detent on crank until the trigger lever is operated either through a
the high bias spring cams over a tooth on the ratchet. The print or spacebar operation.
other end of the high bias spring, which contacts an upright
lug on the sensing shoe arm, pivots the arm. The low bias
Escapement
spring connected to the upright lug on the sensing shoe arm
Torque Bar
produces the low bias. Escapement
Trigaer
Low Bias
Ratchet eeu aS erin
Trigger Lever
Mode Actuating
Bellcrank
aque Upright Eug
es
Detent ————>
é a
ee
High Bias
Spring
(Right Side View)
(Top View)
Figure 8 — Low Bias Operation Figure 10 — Escapement Trigger Disengaged
Finally, high bias is developed for use with the Lift-off The next time a print or spacebar cycle is initiated the
Tape. As the detent on the high bias spring cams over a trigger will not contact the escapement torque bar and no
tooth on the ratchet, high bias is developed due to lugs on escapement operation will result (Figure 11). As the trigger
the bottom of the lift-off tape supply spool preventing the is pulled down during this cycle a forward extension of the
sensing shoe from rotating inward (Figure 9). This causes trigger lever will contact the mode actuating bellcrank and
the high bias spring to flex, producing the high bias. rotate it back to its latched position. This restores the com-
plete correcting mechanism to rest.
One lug on the bottom of the Lift-off Tape supply spool is
shorter than the rest. It is shorter to permit the spool to Escapement
seat completely on the supply spool ratchet in the event Torque Bar
that the sensing shoe is under a window in the ratchet while Escapement
the operator is loading the tape. { Trigger
Mode Actuating
Bellcrank
High Bias
Spring
-188-
CORRECTING TAPE LOAD
When the correcting tape needs to be changed, the tape Toggle
load lever is moved to the right to the load position (Figure Pt Spring
12). The load lever performs three functions to facilitate Extension Tape Load
installation and removal of the tape. Ribbon Load Lever Notch
Lever
1. A guide roller mounted on the rear of the load lever
pivots forward,
Ratchet
LOAD INTERLOCKS
A toggle spring holds the tape load lever in either the load Figure 14 — Take-up Spool Detent
or type position (Figure 13). An extension on the toggle
spring engages a hole in the ribbon load lever so it cannot
be moved to the load position while the tape load lever is in
the load position. When the ribbon load lever is operated,
an extension on the ribbon load lever enters a notch in the
tape load lever to prevent operating the tape load lever to
the load position.
Ribbon Toggle
Load Lever Spring
Extension Ribbon Load
Tape Load
Lever
-189-
“CORRECTING” MECHANISM ADJUSTMENTS
if, Correcting Keylever Side Play — Adjust the keylever Mode Actuating Bellcrank — Form the lug on the
mounting screw so the correcting keylever has mode actuating bellcrank so the bellcrank overthrows
.001°-.004” side play. the mode latch by .005’’-.010” when the escapement
trigger lever is fully operated.
eel |e ON 00a Check this adjustment on the spacebar
(0,03-0, 10mm) or print
escapement cam lobe, whichever supplies the least
ele amount of overthrow.
Escapement
Trigger
(Top View) Mode Actuating
Bellcrank
Fully
2 Backspace Keylever — Form the backspace keylever Operated
so that it centers in the notch on the correcting key- Lug
lever.
Mode Latch
Backspace
Keylever
Correcting
Keylever 0,13,25mm)
Notch (Right Side View)
Centered
.005"'-.020”
Escapement (0,13-0,51mm)
Torque Bar
5: Correcting Keylever Link — Adjust the correcting
keylever link clevis so that the mode latch releases the
mode actuating bellcrank at the same time or slightly
before, the backspace cam is released. renee:
Mode Actuating
Bellcrank ©) Releases at
Same Time or
O Slightly before BS Mode Actuating
Cam releases Bellcrank
Mode Latch
Released
—— —~
-190-
6. Velocity Control Bracket — Adjust the velocity con- Correcting Torque Bar Link — Adjust the correcting
trol bracket so that the back-up tab on the bracket torque bar link to just span the distance between the
has a clearance of .001”-.006” with the correcting torque bar and the mode actuating bellcrank with the
torque bar with the carrier positioned at the extreme bellcrank latched at rest.
left margin.
Mode Correcting Correcting
Actuating Torque Bar Torque Bar
Correcting Back up ,001'’-.006"'
Bellcrank Link \
Torque Bar Tab (0,03-0,15mm)
Just Spans
Velocity
Control
Ape Torque Bar
Stop Bracket
Bracket (Bottom View)
Latched
Clip Correcting
Torque Bar
003'”-.010" |
(0,08-0,25mm)
(Top View)
Power
Frame
Carrier
eu .010"-.015”
(0,25-0,38mm) Velocity Control
Torque Bar Cable
Stop Bracket
Velocity Control
Cable Guide
Correcting
Bracket
Torque Bar
-191-
NOTE: The platen adjustments must be correct before NOTE: This clearance can be easily checked by using
making the following adjustments. the handle end of the 224 backspace adjustment
wrench (P/N 9900369).
11. Card Holder — With the copy control lever forward,
adjust the card holder mounting brackets to satisfy \) .190'’-.210"
the following condition: : (4,83-5,33mm)
.020’'-.030” *
(0,51-0,76mm)
< .,~~ Platen Ribbon Lift Guide
Assembly
Cardholder
Cardholder
Mounting
Bracket \ Carrier
of
Line adjustment (reference adjustment 14).
Cardholder geal .010"'-.020"
Mounting (0,25-0,51mm)
Bracket
Card
Holder eel
Carrier
-192-
b. Vertically so that the bottom of the underscore 16. Lift Actuating Arm — With the torque bar at rest,
clears the top of the tape by .001”-.005” when form the lift actuating arm for a clearance of
the tape is at rest and the underscore is in the .001”-.005” between the lift actuating arm and the
print position. correcting torque bar at the closest point.
rae
Carrier
ima Tape
Mein
Assembly
Lift Actuating he Ze
Ane Nee .001’’-.005
(Rear View) : : Sa (0,03-0,13 )
(Left Side View) ? ie
14. Tape Supply Cradle Fork — Position the cradle fork 17. Lift Arm Latch — Adjust the lift arm latch to satisfy
so that it centers in the groove of the stud mounted the following conditions:
on the tape lift assembly.
a. With the correcting mechanism at rest, position
Tape Supply the lift arm latch front-to-rear so the tape lift
\ Cradle Fork cam follower clears it by .0107-.015.”
Centered
Tape
Lift Assembly
Tape
(Top View) Lift Cam
Follower
15. Cable Guide Lug — Form the cable guide lug on the (OOs ONS e
tape lift assembly front-to-rear so it is centered (0,25-0,38mm) | ,
between the rotate arm assembly and the power (Left Side View)
frame when the carrier is at the extreme left margin.
b. With the print mechanism at rest and the cor-
NOTE: Be sure to maintain a sufficient left-to-right recting torque bar operated, the bottom of the
angle to ensure the velocity control cable cams under lift arm latch must clear the lift cam follower
the carrier when the carrier is at the extreme left
by .005”-.010.”
margin.
Centered ———>—
Cable Guide Lift Arm Latch
Lug /
ea Ae Pe
.005’'-.010”
Cable Guide (0,13-0,25mm)
Lug
f
: Cam
Sea Follower
Left Side
Frame
(Left Side View)
(Left Side View) (Carrier At Extreme Left Margin)
-193-
18. Tape Feed Cam Follower, Front Lug — With the b. Position the bracket front-to-rear so the tape
machine at rest, form the front lug on the follower to clears the card holder by .010”-.020.”
satisfy both of the following conditions:
Card Holder
a. Front-to-rear so the tape feed inhibitor clears .010"-.020”
the correcting torque bar by .004’’-.010” at the (0,25-0,51mm)
closest point along the writing line with all
parts at rest.
CS «
=
CAUTION: Do not type with the tape load lever in
Correcting the load position. The typehead may catch on the
Torque Bar ee .004”-.008” separator wire and result in rotate tape breakage.
(0,10-0,20mm)
.004-.010" a. Left-to-right so that the wire clears the type-
(0,10-0,25mm) head by .060”-.070” when the typehead is in
lx the print position and the load lever is in the
type position,
(Right Side View)
19. Tape Feed Cam Follower, Rear Lug — Form the rear
lug on the tape feed cam follower left or right so it
centers in the notch in the tape feed bellcrank.
.060"'-.070"
ea a)En Centered in Notch Typehead (1,52-1,78mm)
Tape Feed
LL Belcrank
Tape Feed
Separator
Cam Follower
Wire
(Right Side View) (Typehead In Print Position Load Lever
(Top View)
In Type Position)
b. With load lever in the type position, the top of
20. Guide Roller — The guide roller mounting bracket the separator wire should just touch the card
must be positioned to meet the following conditions: holder while maintaining a minimum of .050”
clearance at the bottom of the upright portion
a. Position the bracket up or down so the used of the separator wire.
tape is centered on the take-up spool.
Touches
Take-Up
Form =a
Guide Roller Spool
fr Holder
Mounting Bracket
Separator
Wire
-194-
CG, With the load lever in the load position, the top
of the separator wire must clear the card holder
by at least .120.”
[nn Card
Holder
Separator Wire
prone
(Right Side View) (Load Position)
22. Paper Guide Lug — Form the paper guide lug front-
to-rear so that it clears the platen by .040”-.050.”
\ | Platen
.040"-.050"
<=> —~—~—1021,.27mM)
23. High Bias Spring — Form the upright tip of the high
bias spring in or out so that the sensing shoe clears
the lugs on the tape supply spool when the mecha-
nism is at rest.
Sensing Shoe
Clears
(Top View)
-
-195-
MARGINS AND LINELOCK OPERATIONAL THEORY
The purpose of the margin mechanism is to allow the stop has a margin set lever attached to the pin and slider
operator to vary the length of the writing line. This is assembly. The margin set levers extend through a slot in the
accomplished by two margin stops and a margin rack front case of the machine to make them accessible to the
(Figure 1). The left and right margins are determined by the operator, Either margin stop may be repositioned by push-
position of the margin stops on the margin rack. The left ing the margin set lever to the rear to disengage the pin
margin stop is used to limit carrier travel to the left. from the rack, then, by sliding the margin stop along the
rack to the desired location. A line on each margin set lever
The right margin stop first operates a warning bell which serves as a pointer to indicate the position of the margin
alerts the operator when the carrier approaches the right stop in relation to the scale on the front of the case. A
margin, then locks the keyboard to prevent further typing. pointer, located on the front of the carrier, indicates the
position of the carrier (Figure 1).
Depression of the margin release keylever allows typing
beyond the left and right margins by rotating the rack. This The left margin stop controls the left margin. When the
disengages either margin stop from the line lock bracket on carrier is returned by the carrier return mechanism, an
the carrier. extension of the left margin stop is struck by the margin
stop latch pivoted on the linelock bracket attached to the
The margin rack is a flat rack containing teeth along its rear carrier. This action forces the margin rack to the left to
edge. The number of teeth per inch in the margin rack unlatch the carrier return mechanism and leaves the carrier
corresponds to the pitch of the machine. resting at the left margin position.
Each margin stop has a pin and slider assembly that meshes
with the teeth at the rear of the margin rack. Each margin
Pin And
Slider Assembly
Right Margin
e : eae Stop
Margin
os Rack
a
Left Margin Margin
Stop Set Lever
Line Lock
Bracket
es)
™ Bellclapper
MARGIN RELEASE
The margin release mechanism allows an operator to type
beyond the left and right margins without changing the
Bell oe & ) position of the margin stops. The margin release operates
by rotating the margin rack so the margin stops move
Bellringer
ee Bail
upward out of the path of the margin stop latch on the
linelock bracket (Figure 5).
Figure 2 —'Bellringer
LINELOCK The margin release keylever pivots at the left side of the
If the typist continues typing after the bell rings, the key- keyboard. Depression of the margin release keylever causes
board is locked after several spaces to prevent typing in the the rear of the margin rack to rise. A lug on the left end of
margin. The keyboard is locked by forcing a special inter- ‘the margin rack remains in the path of the margin stop
poser into the selector compensator tube to prevent the latch to unlatch the carrier return if it is operated with the
depression of any other interposer (Figure 3 ). margin release keylever depressed. An extension spring
restores the mechanism and holds it in the rest position.
As the carrier approaches the right-hand margin, the bell-
ringer bellcrank moves into the path of two upright tabs on Margin
the linelock bracket. This causes the bellringer bellcrank to Rack Lug Margin Stop a
pivot about its mounting stud and cam the bellringer bail to Latch
the front of the machine. An extension of the bellringer Extension
bail forces the keyboard lockout interposer down and into Spring
the selector compensator tube. This action in turn prohibits
any further depression of the selection keylever interposers
into the compensator tube until the linelock mechanism has
restored to its normal rest position.
Bc
Compensator Tube
P* (>
: |
i Line Lock7 ,‘ 3/ Right Margin
Bracket (Left Side View) Stop
. Ss Right Margin Stop /? ' ~aa=e™
-198-
c, Level 3 — 7X1, 7X3, 7X5 form margin release
INS AND LINELOCK ADJUSTMENTS
final stop.
Figs
1. Margin Rack Horizontal — The margin rack must rest 7X1 — 7X3 — 7X5 [
on a horizontal plane.
a. Level 1 — 7X1, 7X3, and 7X5 adjust margin
release lever,
Level 3
7X3 — 7X5
Margin Stop Pin
Linelock Bracket
Horizontal
Bellringer Bellcrank
aN
Left-Hand Margin
Release Lever
7X3 — 7X5
.050"’-.060"'
(1,27-1,52)
Level 2
(Right Side View)
-199-
4. __ Bellringer Bail Extension — Form the bellringer bail
extension up or down so the character keybuttons
lock when the red pointer is directly above the right-
hand margin set lever.
Bellringer Bail
Selector Compensator
Bellringer Bellcrank
Linelock
Bellri
Seay Bracket
Bail
Bellclapper Bellcrank
ao serra
Bellringer Bail Pa
c .015"-.025"
(0,38-0,64)
-200-
COVERS OPERATIONAL THEORY
There are three types of covers: tilt-up, console mount, of the cover material has been removed on the rear side to
and ring mount, First, we will describe the tilt-up covers, permit the guide to slide off easily.
and then the differences between them and the other two
types, The paper table is connected to the center cover assembly
by two screws and two brackets. The paper table pivots on
TILT UP COVERS two studs mounted on the bracket to allow the platen to be
The cover assembly is composed of three major sections. removed from the machine.
They are the top cover, center cover and bottom cover
(Figure 1). A margin scale is attached to the lower lip of the top cover.
The scale is graduated to correspond to the pitch of the
The center cover assembly has the paper guide attached to typewriter. The margin scale is attached to the top cover by
it. The paper guide may be removed by sliding the guide to an adhesive that becomes active when IBM cleaning fluid is
the extreme right and pulling straight downward. A section applied.
Top Cover
Paper Table
Paper Guide
Margin
Scale
Center Cover
Bottom Cover
COVERS
TOP COVER HINGE CENTER AND BOTTOM COVERS
The top cover is attached to the center cover by a hinge at There are three basic levels of center and bottom covers
the rear. The hinge brackets are adjustable front to rear to used on the ‘Selectric’ typewriter. The level 3 cover has
allow for proper fit between the top cover and center cover. been used since 1965 and is the easiest to identify. This
The hinge contains a detent that prevents the top cover cover has a latch extending vertically just inside the right
from falling when it is in the raised position (Figure 2). and left side of the center cover (Figure 4). The absence of
the level 3 cover latches identify a level 1 or level 2 cover
which are similar to each other.
(Level 1)
Center Cover
Top Cover
AB a
See as Vi
| Se
Cover Latch
(Level 2)
Ano
Detent Detent
Top Cover
Latch Mounting
Bracket
Latch Bracket
Cover Latch |
(Left Side View)
Spring Clip
-202-
The level 3 bottom cover has the vent positioned in a slot at MOUNTING BRACKETS
the rear. The rubber mounting to suspend the typewriter The machine mounting brackets are attached to the
inside the case is also contained within the bottom cover machine frame and are adjusted vertically, A latch lever
(Figure 5). (Figure 7) locks the machine to the rubber mounting foot
on the left side of the machine (Figure 5).
The level 1 and level 2 center cover assemblies have the vent
grille mounted in the rear by a plate. Slotted holes in the
plate allow the vent to be removed without removing the
plate from the center cover, The level 1 bottom case is held
in place by a screw at the center rear,
(|
Vent Grille
Rubber
Bushings
The level 2 bottom case is held in place by friction fit and
does not use the rear mounting screw (Figure 6).
Bottom Cover
Bottom Cover Front Mounting
Rear Mounting
Snap-In Brackets
ae)
oo
(Bottom View)
Mounting Nut
(Level 1)
Mounting Screws
Center Cover
(Level 1)
Top Cover
(Level 2)
(Raised Position)
-204-
3. Hinge Spring (Level 1 Only) — The hinge spring b. The platen will clear the covers with the copy
should be positioned front-to-rear so the top cover lever operated to the extreme front and rear
hinge is detented and held in the open position. position.
Platen
Center Cover Hinge Spring
Top
Cover
(Bottom View)
Center ie
Ce (Left Side View)
a -020”-.040”
(Level 2) (0,51-1,02mm)
SS x
Rear Cover (Level 1 )
Rubber Mount
Center
Cover
NOUN
—)
= 4
ies) {sam
(34,72mm)
1
PEBROOORAgQgAEaE
Se eee se aa | Cover Parting
a Yo a oe
ui HAT AAO AEA Ope f
Bottom
Cover
Cover Latch ‘
(Oo) Keyboard !
Side Frame
=
vy
Shock
Mount
Mounting
Mounting Bracket
Bracket (Level 2)
(Level 2)
CARDHOLDING PLATEN OPERATIONAL THEORY
The purpose of the cardholding platen is to keep cards from held by either the top or the bottom. A movable card stop
slipping while being typed on. The blade of the cardholding is mounted on the blade to assist in positioning the card
platen has a groove under both edges to allow a card to be laterally in the card slot (Figure 1).
Card
Stop
| Groove
The purpose of the dead key disconnect is to disable the With the control wheel rotated away from the operator, the
dead key mechanism and allow normal escapement for dead dead key mechanism operates normally. With the control
key positions. This is accomplished by a cable which pivots wheel rotated toward the operator, the dead key
the dead key cable away from the finger on the dead key mechanism is disconnected and escapement occurs for dead
bail. The disconnect cable is controlled from the keyboard key positions (Figure 1).
by a wheel mounted next to the tab set and clear
key button.
L--------
Disconnect Cable
Bottom View
Disconnect Cable
Dead Key -,
Indicator
Cable Sheath
Disconnect Cable
i/
Cable Clamp Qo Di
(Bottom View)
-210-
DEAD KEY MECHANISM OPERATIONAL THEORY
The purpose of the dead key mechanism is to prohibit In order to prohibit escapement a 7th selection bail is
escapement on certain predetermined keyboard positions. installed in the keyboard. With the typewriter sitting on its
This mechanism is used with several foreign keyboards. We back, the dead key bail is the bottom bail. The interposer
will refer to the Trilingual keyboard for discussion purposes for a dead key position has an extra lug to operate this bail.
(Figure 1). Attached to the bail is a finger over which the eye of a
cable is located. This cable is very similar to the cable used
On the Trilingual keyboard the characters in position 41 to control impression. The sheath of the cable is held rigid
and 42 are accent marks used with the vowels in certain by two clamps, one for each end, mounted to the power
words to indicate pronunciation. These are “‘dead key” frame. The rear end of the cable is attached to a hole in the
characters and when they are typed, the carrier does not bottom of the escapement trigger (Figure 2).
escape. The next character typed will appear directly
beneath the accent mark.
QMOROOIYOOME
| 5 re Pein le wesw eS Se Se a)
Dead Key Positions
ASOMOMWIWOOC
2 6 1O iQ 18 22 26 Se SB 42
Ceecoousise
Figure 1 — 74 Trilingual Keyboard
Spring
Window
Escapement
—e _ Trigger
Clamps
Dead Key
Interposer
1. Rear Cable Clamp — Adjust the cable sheath under Front Cable Clamp — Adjust the cable sheath under
the clamp for .485”-.565”> movement of the cable the clamp so that the escapement trigger is pulled
when a dead key position is operated. .030”-.060” past the spring window.
(Level 1)
Cable Clamp
(Level 2)
-212-
INDEXING DEVICE OPERATIONAL THEORY
The purpose of the double indexing device is to provide a The double indexing mechanism can be locked out for
second index operation for each carrier return operation. normal linespacing. To lock out the double indexing
operation, the mode switch, mounted above the on-off
Double indexing is accomplished in the following manner. switch lever, is rotated toward the front of the machine.
When the carrier return button is depressed, a normal The mode lever, through a link and locator, loads the
indexing and carrier return operation occurs. Motion from tripper and tripper shaft to the left so the tripper rotates
the carrier return shoe bellcrank through the interlock shaft between the index and carrier return keylever pawls when
rotates the index trip shaft. The tripper, mounted on the operated. When the tripper rotates between the index and
trip shaft, rotates downward, pulling the index keylever carrier keylever pawls, normal linespacing will occur.
pawl down. The index keylever pawl trips the index
interposer, causing a second index operation.
Index Keylever
Paw!
Tripper
Carrier Return
“t———__ Shoe Bellcrank
a
Mode Lever
Locator
Bellcrank Bracket
Cable Sheath
Flush
Tripper
Minimum Clearance
4. Side Frame Clamp (Level 1 Only) — Adjust the cable
sheath under the side frame clamp so the index
keylever does not choke off when depressed.
.020"'-.035"'
(0,89-1,14mm) VA
Locator
Positive Engagement
Positive Disengagement
-214-
EXTERNAL RIBBON CONTROL OPERATIONAL THEORY
The external ribbon control is designed for customers with link connects the control lever and the control bellerank.
applications that require frequent changes of a bicolored When the control lever is moved front-to-rear, the control
ribbon by allowing the operator to select stencil, black or bellcrank pivots on its mounting stud. The control
red ribbon positions without lifting the cover. bellcrank causes the lift control lever to pivot. Connected
to the lift control lever is the lift control link. The lift
The control lever is located on the left side of the carrier. control link for the external ribbon control functions the
The operation and appearance is similar to the impression same as the lift control link on the standard fabric ribbon
selector lever (Figure 1). mechanism.
Flat Link
Ribbon
Control! Lever Ribbon Lift
Cam Follower
Ribbon Lift
Ribbon Lift Cam
Control Link
Print Sleeve
Wire
Link
Carrier
Flat Link
Centered
Ribbon
Feed Pawl
Stencil Position
Ribbon
Control
Lever
.030"-.045"'
(0,76-1,14mm)
Lift
Control
Link
Control
Link
Clevis
-216-
VELOCITY CONTROL OPERATIONAL THEORY
The manual velocity control provides the operator with a wheel rotated away from the operator, all keyboard
means of controlling the automatic velocity control feature, positions will be low velocity, The control wheel must be
A control wheel mounted just to the right of the on-off held in this position. When the control wheel is rotated
keybutton determines keyboard velocity, When the control toward the operator, the keyboard will be in high velocity,
wheel is in the middle or normal position, the keyboard is This position is detented and need not be held (Figure 1).
in the automatic velocity control mode. With the control
Keylever
Low Velocity
Cam
Y)
ie Cy | j Low Velocity
Cam Follower
Low Velocity |] AF
e7
Vane 1 Ke
Cam Follower
Figure 2A — At Rest 2. Low Velocity Link — Disconnect the clevis from the
low velocity .latch. With the machine at rest and the
Velocity
Selection low velocity vane against the tail of the interposers,
Lever adjust the clevis .020”-.025”’ past the end of the slot
in the low velocity latch.
Low Velocity
ane
Low Velocity Latch
Cam Follower
Low Velocity
Latch
Velocity Control Link
Cam Follower
The purpose of the pin feed platen is to feed continuous The platen core is keyed to the right hand pin wheel body.
forms (Figure 1). This is accomplished by pin wheel assem- The pin wheel body is setscrewed to a hexagon shaped
blies, on each end of the platen which engage perforations platen shaft and rotates with the shaft whenever the platen
along the outside edges of the form. Platen cores come in is indexed. Each pin wheel body contains 9 pins sym-
lengths to accomodate most standard width forms. metrically spaced around its surface. A cam mounts over
the hub of the pin wheel and fits into a guide slot in each
During operation, the feed roll release lever should be for- pin. Mounted onto the cam is a control plate which pre-
ward in the released position because the feed rolls are not vents the cam from rotating. The cam control plate is pre-
required to feed the paper. vented from rotating by an anchor rod. The anchor rod
extends the width of the platen and is mounted to each side
of the center cover,
iG
Body
Anchor
Platen Cam Anchor be Rod
Shaft Rod
Bun o Control
Pin Guide f Plate
Slot Setscrews
Platen
Core
Pin Wheel
Assembly
a
ees
Platen
Cam Control Ratchet
Plate
Adjusting
Screw
Cam Control
Cam ‘Plate
Cam
Control
Spring
Plate
Figure 2 — Pin Wheel Assembly (Right Side View) Figure 4 — Paper Guide
Variable Driver
Shaft ‘
\ Platen Ratchet
~ O @ Compression Spring
2
Variable
Shaft
Figure 5 — Card Holder
Guide
BAIL ROLLERS
Large diameter bail rollers are available for use with the pin
feed platen to aid in keeping the form paper flat against the
platen surface. :
Figure 3 — Platen Ratchet And Variable
-220-
PIN FEED PLATEN ADJUSTMENTS
1. Platen Core Lateral Position (Level 1) — Loosen the 3. Paper Guide — Form the front extension on the paper
locknuts on both ends of the platen and center the guides front-to-rear for a minimum of .010” clearance
core, Turn locknuts in and tighten, between the underside of the guide and a fully
extended pin as it passes under the guide.
Core Centered
.010” Min.
(0,26mm)
bt
‘S
7
Paper Guide ,
an
yy, y
Lock Nuts
(Front View)
Pin
Core Centered
(Right Side View)
Centered On
2. ._ Pin Wheel Assembly — Adjust the cam on the control Pitch Mark
plate so the pins are fully extended immediately after
passing into the slot of the form guide.
.002"'-.005"
(0,05-0,12mm)
Cam Control
Plate
VVVVVVVVVVVVVVVVVV
Adjusting
Screws
AONE a
(0,13-0,38mm) — aha
‘Gardholder
ag el
Ribbon ae
Lift Guide ats
pas,
i].
LL .035'" Max.
) e (0,89mm)
any ni: avenKeue HtsQi) aii aa
aaeents
Bracket
: iq of}
iosdwoe Te sbite
Carrier
The purpose of the shift sensing mechanism is to move the crank is mounted to the rear of the vane and held against its
low velocity vane to the left when the machine is in the spring tension in a counterclockwise position by the shift
upper case mode, This allows certain predetermined key- sensing cable, The other end of the cable is mounted to 4
board positions that are low velocity in lower case, to be plate on the rear of the shift arm, When the machine is
high velocity in upper case, This is used on keyboards with shifted to upper case, tension on the sensing cable is relaxed
the ten key numeric inset such as the 056 and 065 OCR and the bellerank spring rotates the bellcrank clockwise, As
keyboards where the numerals 8 and 9 are above the the bellcrank rotates, it pushes the low velocity vane to the
comma and period (Figure 1). left. This allows certain interposers which have low velocity
in lower case to now have high velocity in upper case
With the machine in lower case, the low velocity vane is because the lugs on the low velocity vane are not in front of
held to the right by a flat spring. The vane actuating bell- the interposers.
ty
Low Velocity
Shift Arm
Low Velocity
Vane
Shift Sensing Cable
Bellcrank
Flat Spring Spring
is Vane Return Spring — Ensure that the low velocity 4. Rear Cable Clamp — Adjust the sheath under the rear
vane does not bind off on the vane return spring. cable clamp so the sheath is flush with the clamp
bracket.
Cable
5
ee Vane Bellcrank — Adjust the bellcrank left-to-right so
the vane moves .095”-.105” to the left when actu-
ated. 5. Front Cable Clamp — Adjust the sheath under the
clamp so the front cable anchor does not restrain the
actuating bellerank when the machine is in upper
case.
Control
Lever Front Cable Clamp
Spring Vane
Return Spring
Vane Bellerank
Low
ER Velocity
Latch Link Low Velocity
Vane Bellcrank Vane
Control Bracket
.095” - .105”
2,41 - 2,67mm
Vane
Return Spring
Cable
Low Velocity
Vane Shaft
Low Velocity
Vane Bellcrank Center Cable Clamp
Vane Control
Bellcrank Bracket
-224-
COUNTER OPERATIONAL THEORY
The purpose of the stroke counter is to record actual usage the cycle shaft operates, The left-hand dust shield has a
of the “Selectric,” “Selectric” II and Correcting “Selectric” portion removed to allow the counter to be read,
typewriters. This is accomplished by a nonresetting 9
mechanical counter mounted inside the power frame above Stroke counters for the ‘Selectric,’ “Selectric” Il and
the left-hand cam of the cycle shaft assembly (Figure 1). Correcting ‘‘Selectric’ Typewriters are available with a
10:1, 100:1 or 240:1 ratio. This means that for every 100
The stroke counter arm is spring loaded against the cam and print operations, the 100:1 ratio counter will advance 1,
moves up and down with the camming surface each time etc.
San?
\
Stroke Counter
as Counter
Cam Follower
There Are No Adjustments For The Stroke Counter.
N N ro
9. On machines without an adjustable collar, check to 2. Remove the shift interlock spring, the shift release
see the shims remain in place, Check to see that arm spring and the shift detent spring.
proper end play (,001°-,006"’) is present, Reshim if 3. Remove the C-clip from the operational shaft and
necessary, remove the shift clutch ratchet.
10, The drive belt or cycle clutch can now be removed.
11. The following adjustments should be checked after 7X1
the cycle shaft is replaced: 4, Remove the interlock,
Idler gears 5. Remove the detent arm.
Cycle shaft end play 6. Disconnect the shift release link,
Cycle clutch spring 7. Remove the shift release arm.
Cycle clutch latch bite
Damper spring (if used) 7X3-7X5
Filter shaft timing 4. Disconnect the shift release link,
mmo
nogePrint shaft timing 5. Remove the shift support bracket screw.
6. Remove the shift support bracket, interlock and shift
ROTATE SELECTION DIFFERENTIAL REMOVAL release lever as an assembly,
(Mech. Code 702, 704, 711, 721, 723) 7. Remove the detent arm.
-228-
CORD REPLACEMENT “Dh FRAME” PAPER FEED REMOVAL
(Mech. Code 722)
1. Perform cover removal.
2. Remove dust shields, The feed rolls may be removed from the “‘A frame” in the
3, Remove both cords and hand cycle the machine until following manner:
the mainspring tension is relaxed,
4, Disconnect the carrier return unlatching link, Carefully spread the feed roll arm assembly and remove the
5. Manually latch the carrier return mechanism and front feed roll. Pivot the rear feed roll toward the front and
rotate the turning wheel, while counting escapement remove,
shaft revolutions, until the mainspring is wound the
proper number of turns (Figure 3), The “A frame” is removed in the following manner:
6. With the carrier to the right, connect the cord to the
carrier return cord drum, position cord to the left 1. (“‘Selectric” Il and Correcting “Selectric”
over the idler pulley, around the left rear corner Typewriters) Remove detent release lever and stud,
pulley and connect to the carrier using scissor clamps 2. Remove the platen ratchet detent.
or the pusher end of a springhook (Figure 1). 3. Remove the index link from the index pawl without
7. Hold the slack out of the carrier return cord and disturbing its adjustment.
rotate the turning wheel until the carrier approaches 4. Remove index pawl overthrow stop.
the left side frame. Stop hand cycling when the notch 5. (Dual Pitch) Disconnect half backspace links, loosen
in the escapement cord drum is visible. half backspace stop bracket nut and pivot bracket
8. Connect the escapement cord to the escapement cord from under nut.
drum and wrap approximately 1 turn of the cord 6. (Dual Pitch) Remove pitch cam cable from switch
around the drum (Figure 2). pitch sector gear.
9. Thread the cord around the cord tension pulley and 7. Scribe the position of the multiple copy control
connect it to the carrier. detent plate; loosen the screw and pivot the plate
10. Pull the carrier return cord over the left front corner from under the screw.
pulley and connect the carrier return unlatching link. 8. Disconnect both anchor springs. These springs
connect the paper feed assembly to the power frame.
9. Lift the paper feed assembly at the rear; pull toward
the rear of the machine and remove the assembly.
NOTE: Removing the “‘A frame” assembly will allow
easy access to rotary backspace, escapement bracket
'_/ 4__. Fold Eyelet Back and transport cords.
Into Cord Drum
REMOVAL OF 27 TOOTH RATCHET ASSEMBLY
(Mech. Code 720)
This Spring Should This Spring Should 12. ail Ped Jenene lever.
Be Wound 7 Turns Be Wound 5 Turns
ESCAPEMENT RACK REMOVAL (DUAL PITCH) Me Remove the mainspring backplate screws and remove
(Mech. Code 707) the paper feed support bracket.
{Pas Slide the mainspring backplate from the escapement
ih Remove the platen, deflector and feed rolls. shaft, leaving the backspace bellcrank in its position
2. Disconnect the margin pitch link from _ the in front of the ratchet.
escapement rack gear. Shs Remove the cable tension spring, arm and spacer.
3% Loosen the switch pitch sector gear screws and move 14. Remove the CR/BS cable drum assembly and
it to the rear of the machine. disengage the cable.
Remove the escapement rack gear. Isr When installing a new drum assembly, engage the
&
n Remove the escapement rack bearing plate and cable, orient it properly and install the cable tension
compression spring. spacer, arm and spring. This procedure will hold the
Disconnect the lower half backspace link and remove cables in place.
the half backspace intermediate lever and bellcrank 16. Reinstall the remaining parts in reverse order.
link, VT The following adjustments should be checked:
Remove the half backspace bellerank mounting screw Paper feed support
and spacer from the power frame. Switch bracket
Operate the tab to get the escapement pawl out of Mainspring hub
the escapement rack. As you pull the escapement Escapement shaft collar
rack from the machine, disengage and remove the half Transport cable tension
backspace bellcrank. Backspace motion
The following adjustments should be checked after Backspace latch height
the escapement rack is replaced. Index interlock shaft
Half backspace motion Index interlock paddle
Sie Half backspace rest position
ohn
ee
an
gon
pied
oY Index multiplying lever stop
Escapement rack gear
Escapement rack gear lower stop COMPENSATOR BALLS REMOVAL
Switch pitch sector gear (Mech. Code 721)
ho
aa Pitch cable
1. Remove covers.
MARGIN RACK AND RAIL REMOVAL (DUAL PITCH) 2. With the machine tilt up, raise the interposer tails.
(Mech. Code 710) HINT: The interposer can be held out of the
compensator tube by inserting a drive belt between
Remove the margin rack gear toggle spring and gear the filter shaft and interposers.
guard. 3. Remove the right-hand end plug.
Loosen the margin pitch link guide bracket. 4. The compensator balls may now be removed by
Disconnect the margin release bracket spring. carefully tilting the machine to the right. The
Loosen the margin release bracket screws and slide compensator balls may be cleaned in IBM cleaning
the margin release bracket to the rear. fluid.
Disengage the margin sliders by holding the margin 5. Reverse procedure for installation.
set levers to the rear. Slide the margin rack out of the CAUTION: There must be a compensator ball on the
machine. Note the position of the margin rack spring, outside of position 0 and position 43 interposers.
washer and bushing. 6. The compensator tube adjustment must be made
Lift the margin rail out of the machine. after replacing the compensator balls.
Remove the margin rack gear if necessary.
The following adjustments should be checked after LUBRICATION
the margin rack and rail are replaced.
a. Margin pitch link guide bracket The “Selectric” Typewriter will not operate dependably
b. Margin rack gear and reliably if it is not thoroughly and properly lubricated.
G: Front margin rack gear stop
Use IBM No. 10 oil on the following:
CARRIER RETURN/BACKSPACE CABLE DRUM a Print shaft wipers
ASSEMBLY REMOVAL (DUAL PITCH) b Cycle shaft bearing
(Mech. Code 724) (oF Margin rack bearing
d. Margin stops
Position the carrier at the extreme right. e Carrier shoe
Remove the switch and swing it dut of the way. f Rotate detent guide, upper and lower ball
Carefully remove the mainspring. sockets, tilt detent pivots
Remove the backspace bellcrank retainer. g. Motor
Mm
NH
BW Remove the pin and C-clip connecting the driver links h, Selection bail rollers
to the driver. i Index pawl assembly
Remove the index interlock link and the left-hand j All power operated links and clevises at both
index interlock shaft clip, Slide the index interlock ends
shaft toward the right, k, Ribbon feed and reverse plate
Remove the index multiplying lever stop and switch il B/S intermediate lever
bracket screws. m. Differential assemblies
Remove the mainspring hub. n. All functional parts and pivots in operational
Remove the two screws that mount the paper feed box assembly
support to its bracket. Oo. Tilt arm pivot and rotate link stud
Disconnect the backspace bellcrank spring. p. Rotate arm pivot and rotate link pivot studs
-230-
Carbon ribbon drive spring and bearing
Power frame center bearing
Platen bushings
oe
See All other rotating or pivoting members at the
bearing area which are not specifically excepted
in the listing following
-231-
33130
s}anpol
UOISIAIG
Jauio}s
Cut Along
Dotted
Line
21. Line Position Reset Lever “Selectric”? Typewriter —
Form the right-hand extension of the line position
reset lever to obtain .001”-.010” clearance between
the detent roller and the lever with the lever at rest.
Form the detent arm so the lever overlaps the detent
roller by the thickness of the lever. Machines
equipped with a 54-tooth detent arm should have
.005”-.015” between the lever and the C-clip.
24 & 27 oF
Tooth Tere
Roller oller
Lever
Overlap ]| .005"’
The | aa To
Thickness 015"
Of Lever 0,12-0,38mm
Seema kaa
Form Here To
Give Clearance
Detent Roller
.001°'-.010"
(0,03-0,25mm)
In Rest Position
Line Position
Reset Lever ae
Positive
Clearance
-156-
RIBBON FEED
FILM RIBBON OPERATIONAL THEORY
The ribbon feed cam, which is keyed to the print sleeve,
supplies the motion for ribbon feed. The motion from the
The purpose of the Film Ribbon Mechanism is to lift the cam is transmitted through an adjustable stud to the cam
ribbon into the path of the typehead during a print opera- follower, which drives the feed pawl (Figure 2). The cam
tion; and to feed the ribbon from the supply spool to the follower mounts on a bracket that is fastened to the front
take-up spool, carrier casting by two hex-headed screw, An extension
spring, anchored to one of these screws, loads the cam fol-
The film ribbon mechanism mounts on and moves with the lower against the cam. The feed pawl mounts at the top of
carrier assembly, The supply spool of ribbon mounts on a the cam follower by a shouldered rivet and is spring loaded
permanent supply spool on the left side of the carrier, Due into engagement with the ribbon feed and lift wheel.
to the inner-connection between the plastic core of the
supply spool and the permanent supply spool, both spools Ribbon Feed and Lift Wheel
rotate as a unit during a ribbon feed operation, As the
ribbon comes from the supply spool, it threads around the Feed Pawl : * Shouldered Rivet
ribbon circuit to the take-up spool, The take-up spool is a
disposable, transparent spool mounted on the right side of
the carrier. Once the ribbon has been used and fed to the
take-up spool, both the take-up spool and the plastic core
Stud
from the supply side are removed and discarded. The new
ribbon to be installed comes equipped with its own take-up
spool fastened to the end of a clean leader (Figure 1). Cam Follower 3
Load Spring
Stencil
Lever Carrier
Assembly
Pressure Low Lift Feed Windows
Roller Disposable
Take-Up Spool
Feed Roller
Med. High
oe Tare
Load Lever