US2760457A - Sewing machine - Google Patents

Description

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SEWING MACHINE:

Feb. l5, 1951 11 ShSBtS-Sheet l1 United States Patent SEWING MACHINE Hector Rabezzana, Fenton, Mich.

Application February 15, 1951, Serial No. 211,147

3 Claims. (Cl. 112-221) The present invention relates to an improved sewing machine.

It isanV object of the present invention to provide an improved sewing machine which is simple in construction, economical of manufacture, and reliable and ethcient in operation.

Another object of the present invention is to provide an improved sewing machine having a novel construction by virtue of which the vibration accompanying operation of the machine is greatly reduced permitting the machine to beconstructed of strong lightweight materials greatly reducing the over-all weight of the machine without objectionable vibration.

A further object of the invention is to provide a novel and improved sewing machine construction which is readily adaptable for embodiment in sewing machines of the chain stitch type or lock stitch type whether having oscillating shuttles or rotating shuttles mounted on vertical or horizontal axes and whether having single or double cycles of movement of the shuttle for each cycle of movement of the needle bar assembly.

Another object of the present invention is to provide an improved sewing machine capable of operation at substantially increased speeds without objectionable vibration.

A further object of the present invention is to provide animproved sewing machine having a frame formed of strong lightweight castings or stampings and having covering stampings the shape and finish of which may be readily varied to change the styling and appearance as desired, without necessitating changes in the remainder of the machine.

Another object of this invention is` to provide an improved sewing machine of the type including a base and an arm or head suppoited on andV extendingabove said base and having a single simplified power transmission means extending between the upper and lower parts of the machine and which has no reciprocating parts.

A further object is to provide an improved sewing machine of the above mentioned type having an improved power transmission means including improved means effective for interconnecting the operating mechanisms in the head and base for operation in timed relation to each other.

It is also an object of the present invention tok provide an improved sewing machine of the type having a base and an arm or head supported on and extending' above the base, and having an improved' novel construction in which the mechanism housed in the base is. completely divorced froml the mechanism housed inv the: arm except for a single readily disengageable power transmission element thereby permitting the upper and lower assemblies to be separately assembled, run and tested.

Itis also an object of the present invention to provide an improved sewing machine having an improved drive means for the needle bar greatly reducing theA vibration incident to operation of the needle bar drive means.

A further-object of the invention is to provide such an `ice improved needle bar drive means which is dynamically balanced to substantially eliminate vibration incident to operation of the needlebar drive means.

Another object of the invention is to provide an improved needle bar drive means including meansA for dynamically balancing the needle bar to substantially eliminate vibration incident to reciprocation of the needle bar.

Another object of the invention is to provide animproved meansA for providing and takingv up slackv inthe thread and means for dynamically balancing this inrproved means.

lt is also an object of the invention to provide an improved sewing machine havingy an improved and simplied drive means for the shuttle and the material feeder and including a remotely controlled clutch for'controlling the operation of the material feeder.

It is also an object of the invention to provide an improved materiall feeder mechanism for a sewing machine including readily adjustable means for varying the feed from maximum forward feed to maximum rearward feed.

Another'object is to provide an improved power transmission means for a sewing machine having an oscillating shuttle and by which rotary motion is converted to oscillatory motion.

Another object of the present invention is to provide a sewing machine having improved meansV for lubricating the bearings for the rotating elements thereof.

A further object is to provide such a sewing machine having an improved' lubrication means in which the initial supply of lubricant will' properly lubricate the machine for an extremely long period.

A related object is to provide a sewingmachine having an improved head mechanism incorporating improved means for lubricating the head mechanism and in which all of the rotating parts thereof are lubricated from a single wick.

Another-object of the invention is to provide a sewing machine having an improved material feeder mechanism including a clutch disengageable at any point in the operation thereof and reengageable in only one relative position of the parts to insure proper timing of the material feeder mechanism.

It is also an object of the invention to provide an im'` provedv material feeder mechanism which is compactly mounted within the sewing machine and the controls for which, includingv the clutch thereof, may be operated from the control plate onV theI front ofthe machine.

ItV isY alsoan object of the present invention to provide an improved sewing machine construction comprising upper and lower frame members uponv which are mounted shell elements, the shape and finish of which provide the desiredstyling of the machine and may be readily changed to effect desired changes in the styling.

Another object is to provide a sewing machine of the just mentioned type in which the lighting xture for lighting the work area is permanently mounted on the upper frame member and shines through an openingv in the shell.

A related object is to-provide such a machine in which a covering portion of the shell is mounted for readyl removal permitting easy access to the light iixturemounted on the frame member.

Another object of the present invention is to provide anl improved sewing machine of the: above described type including upper and lower frame members individually carryingl operating mechanisms which are completely divorced except` for a simplii'iedv nonreciprocating drive mechanism disposed externally of the upper frame member and covered by the outer shell elementsY mounted on the upper frame member. A further object of the present invention is tolprovide a sewing machine of the above mentioned type having an improved bobbin Winder mechanism mounted on the shell.

It is also an object of the present invention to provide a sewing machine having an improved darning release mechanism for releasing the pressure on the presser foot, thereby facilitating the use of the machine for darning and in which the formerly applied degree of pressure on the presser foot may be quickly and readily re-applied when the darning is completed.

Another object of the present invention is to provide such a machine in which the plates are mounted for pivotal movement between a position in which they proyvide ramps as above mentioned and a second position in which they overlie the front and rear sides of the machine to provide protection for the machine.

A further object is to provide such a machine in which the plates are mounted for pivotal movement between a position in which they provide ramps as above mentioned and a second position in which they overlie the front and rear sides of the machine to provide protection for the machine.

Another related object of the present invention is to provide a machine of the just mentioned type in which 'the plates have apertures adjacent their upper edges when in the second mentioned postion to which a handle may be connected by suitable snap-in fasteners to provide .simple and inexpensive means for carrying the machine.

Other and more detailed objects of the invention will vbe apparent'from a consideration of the following speciycation, the appended claims and the accompanying drawings, throughout the vseveral views of which like reference characters designate like parts and wherein:

Figure 1 is a perspective view of a sewing machine embodying the present invention;

Figure 1A is an enlarged sectional view of a detail of the structure illustrated in Figure 1;

Figure 2 is an enlarged and elevational view of the right hand end of the machine as viewed in Figure 1, having parts broken away;

Figure 3 is a longitudinal sectional view of the struc- .ture illustrated in Figure 2, taken substantially along the line 3 3 thereof;

Figure 3A is a broken enlarged longitudinal sectional View showing a portion of the lubrication system;

Figure 3B is a broken enlarged transverse sectional view of the structure shown in Figure 3A taken substantially ,along the line 3B 3B thereof;

- Figure 3C is a fragmentary, enlarged, sectional View of a portion of the construction illustrated in Figure 3, taken substantially along the line `lO- 3C thereof;

Figure 4 is a broken transverse sectional view of the structure illustrated in Figure 3, taken substantially along vthe line 4 4 thereof;

Figure 5 is an enlarged end elevational view of the left hand end of the machine as viewed in Figure l;

Figure 5A is a broken transverse sectional View showing a modification of the structure illustrated in Figure Figure 5B is a broken sectional view of the structure illustrated in Figure 5A taken substantially along the line 5B 5B thereof;

Figure 5C is a broken end elevational view showing the light supporting bracket which is broken away in Figure 5 to show other details there;

Figure 6 is a broken bottom view showing parts in section;

Figure 7 is a sectional view of the structure illustrated inf Figure 6, taken substantially along the line 7 7 thereo Figure 8 is a sectional view, similar to Figure 7, illusftrating another relative position of the parts during operation of the material feeder mechanism;

Figure 9v is a sectional view of the construction illustrated in Figure 6, taken substantially along the line 9 9 Figure 10 is a sectional view, similar to Figure 9, illustrating the relative position of the parts of the material feeder control lever adjusted for reverse feeding of the material upon which the machine is operating;

Figure 11 is a broken sectional view of the structure illustrated in Figure 2, taken along the line 11-11 thereof;

Figure 12 is a side elevational view of a modification of the invention showing parts in section;

Figure 13 is a bottom View of the structure illustrated in Figure 12;

Figure 14 is a bottom view showing a further modification of the present invention;

Figure 15 is a longitudinal sectional view of the structure illustrated in Figure 14;

Figure 16 is a side elevational view, partly in section, showing a further modification of the invention;

Figure 17 is a broken sectional View of the construction illustrated in Figure 16, taken substantially along the 17 17 thereof;

Figure 18 is a broken end elevational view showing the right hand end of the machine illustrated in Figure 16;

Figure 19 is a broken end elevational view of a further modification of the invention;

Figure 20 is a side elevational view, partly in section, showing a chain stitch sewing machine embodying the present invention;

Figure 21 is a broken bottom view showing an improved drive for an oscillating shuttle type sewing machine;

Figure 22 is a fragmentary sectional view of the structure illustrated in Figure 21, taken substantially along the line 22 22 thereof;

Figure 23 is a fragmentary elevational view of a modied drive for an oscillating shuttle type sewing machine;

Figure 24 is a broken sectional view of the structure illustrated in Figure 23, taken substantially along the line 24 24 thereof;

Figure 25 is a broken enlarged longitudinal sectional view showing a modified head mechanism;

Figure 26 is a transverse sectional view of the structure illustrated in Figure 25, taken substantially along the line v26-26 thereof;

Vthe line 30-30 thereof;

Figure 3l is a broken transverse sectional view similar to Figure 29,' showing a further modification of the invention;

Figure 32 is a broken end elevational view of a modication of the construction illustrated in Figures l-l3V inclusive, showing the aps in sewing position;

Figure 33 is an end elevational view similar to Figure 32 showing the flaps in carrying position and a handle attached thereto;

Figure 34 is a broken side elevational view of the structure illustrated in Figure 33.

Figure 35 is an exploded elevational View of the needle bar drive mechanism; and

Figure 36 is a view showing the parts illustrated in .Figure 35 in assembled relation and viewing them from the left-hand side as shown in Figure 35.

Referring to the drawings, and more particularly to Figures l to 6, inclusive, the improved sewing machine frame 44. For reasons which will be appreciated from ,a Complete understanding of the present invention, the

arenas? castings of aluminum alloy cr other suitable strong and lightweight material. The lower frame 42 is of hollow construction and houses the shuttle generally indicated at 46 and the material feeder mechanism generally indicated at 48, together with the power transmission mechanism as hereinafter described for operating the shuttle and material feeder mechanism. The upper side of the lower frame 42 is covered by a plate 50 which co-operates with the frame 42 to enclose'the just mentioned apparatus housed within the lower frame 42.

The upper frame 44, which is generallyv L-shaped, is secured to the lower frame by a plurality of screws 52 and so disposed that it extends upwardly from a point adjacent one end of the lower frame 42 and has a horizontally extending arm portion extending along the frame 42 in spaced parallel relation thereto. The upper frame 44 is enclosed in a shell defined by a front stamping 54, a rear stamping 56 and an end cover 58. These stampings may be of any desired shape to provide any appearance characteristics desired. The front and rear shell stampings 54 and 56 are secured to the upper frame member 44 by screws and the end cover 58 is removably mounted on the stampings 54 and 56 by a pin and slot connection (not shown).

The upper frame 44 includes a head portion generally indicated at 60 which carries a needle bar 62, a needle bar drive mechanism generally indicated at 64, the presser foot bar 66, and the lever 68 which provides and takes up slack in the upper thread. The upper frame 44 also carries a pair of aligned spaced bearings 70 and 72 in which is journalled a horizontally disposed shaft 74 extending from the head portion 60 of the upper frame member 44 parallel to the lower frame 42 Vand which overhangs the frame 44 and the shell defined by the stampings 54 and 56, at the right hand end thereof as viewed in Figures 1 and 3. The portion of the shaft 74 overhanging the upper frame member 44 carries a hub member 76 fixed thereto for rotation therewith as by a set screw 78. The hub member 76 extends through the shell and carries a wheel 80 disposed between the upper frame member 44 and the shell and which is secured t-o the hub member for rotation therewith as by screws 82.

Outwardly of the shell the hub 76 carries a ywheel 84, the hub portion of which may be clamped between an annular outwardly facing shoulder 86 on the hub member 76 and a friction disk 88, by a knob 90 having a knurled peripheral portion 92 and a stud portion 94 threaded into a tapped opening 96 extending axially inwardly of the outer end of the hub member 76. The friction disk 88 is secured to the knob 90 as by screws 98. Inwardly of the bearing 72 the shaft 74 carries a thrust collar 100 secured thereto by a set screw 102 for preventing axial movement of the shaft 74 outwardly through the bearing 72, or to the right as viewed in Figure 3. It will be appreciated that axial movement of the shaft 74 in the opposite direction is prevented by the hub member 76 which is secured to the shaft as above described and engages the outer face of the bearing 72.

The sewing machine 40 is powered by an electric motor 104 which is disposed within the vertically extending portion of the upper frame member 44 and is secured to the latter as by screws 166. The drive shaft 108 of the motor 104 extends outwardly through the' shell delined by the stampings 54 and 56 and carriesY a driving wheel 110 which may be formed of hard rubber or other suitable material and has a conical outer surface engaging a peripheral portion of the ywheel 84.

The lowerv frame 42 carries a mairndrive shaft 112 extending longitudinally thereof in parallel relation to the shaft 74 and journaled in longitudinally spaced bearings 114 and 116 (see Figure 6). secured to the left hand end ofthe shaft 112, as viewed The shuttle 46 is Y rin Figures 3 and 6. At its right hand end the shaft 112 overhangs the bearing k116 and carries a thrust collar 118 which is secured thereto by a set screw 120, and

a wheel 122 which is secured to the shaft 112 by a pair of angularly spaced set screws 124 (see Figures 4 and 6). The wheel 122 is disposed in coplanar relation with the wheel mounted on the shaft 74. InW-ardly of the bearing 116, the shaft 112 carries a pinion 126 secured thereto by a set screw 128 and which co-operates with the thrust collar 118 for engaging the opposite axial faces of the bearing 116 and preventing axial movement of the shaft 112 in the bearing 116. The pinion 126 is in constant meshing engagement with a gear 130 rotatably mounted on a shaft 132 extending in spaced parallel relation to the shaft 112 and journaled at its opposite ends in longitudinally spaced bearings 134 and 136 (see Figure 3).

The shaft 132 is held against axial movement in one direction by a thrust collar 13S secured to the shaft by a set screw and engaging the outer axial face of the bearing 136, and in the opposite direction by the engagement of the gear 130 which is held against the inner axial face of the bearing 136 by a split ring 142 received within an annular groove 144 in the surface of the shaft 132. At its left hand end, as viewed in Figures 3 and 6, the shaft 132 is drivingly connected to the material feeder mechanism 48, as hereinafter described. inwardly of the annular groove 144 a clutch collar 146 is mounted on the shaft 132 for axial movement relative thereto and is conected to the shaft 132 for rotation therewith as by the key 148. At the end thereof, adjacent the gear 130, the clutch collar 146 has a radially outwardly extending liange 148 which has a generally circular periphery provided with a radially inwardly extending notch 15G adapted to receive a clutch pin 152 carried by the gear 130, when the clutch collar 146 is in one rotative position of the clutch collar 146 relative to the gear 130. At its opposite or axially inner end, the clutch collar 146 is provided with a second radially outwardly extending ange 154 which serves as an abutment Vagainst which one end of a coil spring 156 is seated. The spring 156 encircles the shaft 132 and its opposite end acts against a washer 158 supported against axial movement to the left as viewed in Figure 3 by a split ring 160 mounted in a co-operating annular groove in the shaft 132. It will be appreciated that in the above described construction the coil spring 156 continuously urges the clutch collar 146 toward the gear 130, thereby tending to maintain or establish driving relation between the gear 13@ and the clutch collar 146.

A clutch release lever 162 is pivotally mounted on the upper frame 44 at the lower end thereof as at 164 (Figures 3 and 4) and extends downwardly through an aperture 166 in the plate 50 and terminates at its lower end in a laterally turned end portion 168 which is disposed betweenvthe flanges 148 and 154 on the clutch collar 1.46. The laterally turned end portion 168 is adapted to engage the clutch collar ange 154 to move the clutch collar 146 to the left as viewed in Figure 3 against the action of the spring 156. Upon sucient movement of the clutch collar in this direction by the clutch release lever 162, the clutch collar 146 is drawn from engagement with the clutch pin 152, thereby breaking the driving connectionl between the gear 13% and the clutch collar 146. Movement of the clutch release lever 162 is effected by means of a handle 170 secured to the upper end of the lever 162. This handle 17) extends outwardly through an aperture 172 formed in a plate 174 mounted in an opening formed in the stamping 54 in the lower front portion thereof, as viewed in Figure l. The handle 170 includes conventional spring means (not shown) for releasably holding it in either end of the aperture 170 and thereby holding the lever 162 either in the position illustrated lor in the position in which it holds the clutch collar out of engagement with the pin 152.

The coplanar wheels 80 and 122, secured to the shafts 74 and 112 respectively, are provided with teeth 176 for co-operation with a iiexible endless belt178 trained over the wheels 80 and 122 and having notches 180 extending transversely thereof and spaced along its inner surface for co-operation with the teeth 176 on the wheels 38 and 122. The co-operating teeth 176 and the notches 188 positively prevent slipping of the belt 178 relative to either frame member 44 for reciprocation along a vertical line by the needle bar drive means 64. At its lower end the needle bar 62 carries a needle 184 which is held in place in a conventional manner by a thumb screw 196. At its upper end the needle bar 62 carries a pin 188 extending at right angles thereto and in parallel relation to the shaft 74. An internal ring gear 190 is mounted on the frame 44 in coaxial relation with the shaft 74 by means of screws 192 permitting rotative adjustment thereof, as hereinafter described.

An arm 194 is secured to the shaft 74 outwardly of the bearing 70 by means of a set screw 196. The arm has a pin portion 198 disposed eccentrically of the shaft 74 and extending in parallel relation thereto. The pin 198 extends outwardly through the ring gear 198 and carries a pinion gear 280 freely rotatable on the pin 198 and 'meshing with the internal ring gear 196. The diameter of the pitch circle of the pinion gear 200 is exactly equal to the radius of the pitch circle of the internal ring gear 190. Outwardly of the ring gear 190 a link 212 is mounted on the pin 198 and secured to the pinion gear 200 for rotation therewith and deiines a cylindrical recess 282 at right angles to the plane of the ring gear 190 and disposed with its axis intersecting the pitch circle of the 'ring gear 190. The pin 188 mounted on the needle bar 62 is journaled in the cylindrical recess 202 in the link 212. The pinion gear 280 and the link 212 are held in place on the pin 198 by a screw 204 mounted in the outer end of the pin 198 and having a head portion overlying a portion of the outer face of the link 212.

By employing a pinion gear 208 having a pitch circle diameter exactly equal to the radius of the pitch circle of the internal ring gear 190 with which it meshes, and by positioning the recess 202, in which the pin 188 mounted on the needle bar is journaled, on the pitch circle of the ring gear 190, a construction is provided in which, upon rotation of the shaft 74, the pin 188 mounted on the needle bar 62 moves in an absolutely straight line. This is for the reason that the hypocycloid becomes a straight line when the diameter of the smaller circle rolling around the inside of the larger circle is equal to the radius of the larger circle. It will now be appreciated that the internal ring gear 190 may be adjusted by loosening the screws 192 so that the straight line path of movement along which the recess 202 in the link 212 moves is parallel to the needle bar 62 or vertical when the machine is in the normal position illustrated in Figure 1.

lever 68 is pivotally connected to a crank portion 216 of the arm 194 iixed on the shaft 74. This crank portion is disposed intermediate the pin portion 198 and the connection of the arm 194 to the shaft 74. The crank portion 216 is disposed eccentric of and extends in parallel relation tothe shaft 74. In the construction illus- `trated in Figure 3, the arm 194 is formed in two parts,

one part forming a hub portion 218 secured to the shaft 74 by the pin 196, and the second part 220 including the pin portion 198 and the crank portion 216. The second part 220 is rigidly connected to the hub part 218 to prevent relative movement between the parts 218 and 220.

The head portion of the upper frame 44 also carries the foot presser bar 66 disposed behind the needle bar 62, as viewed in Figures 1 and 3, and to the left thereof as viewed in Figure 5. The foot presser bar 66 is supported by the upper frame member 44 in parallel relation to the needle bar 62 and for vertical sliding movement. At its lower end the foot presser bar 66 carries the usual foot 222 adapted to hold the material in place during sewing and extend on Opposite sides of the needle 184. The presser bar 66 also carries the conventional thread cutter 224. At itsl upper end the foot presser bar 66 extends into a hollow threaded screw 226 which is threadedly mounted in the upper frame member 44 and of larger diameter than the adjacent portion of the foot presser bar 66. An elongated coil spring 228 encircles the upper portion of the foot presser bar 66 and its upper end engages and acts against the lower end of the screw 226. At its lower end the coil spring 228 acts againstva collar 230 ixed on the presser bar 66. A foot presser bar lifter lever 232 is pivotally mounted on the frame 44 as at 234 and has an upwardly facing cam surface 236 adapted to engage the lower surface of the collar 230 and effect a raising of the presser bar 66 upon pivotal movement of the lifter lever 232 in Ia clockwise direction, as viewed in Figure 5. The lifter lever 232 also has a surface 238 continuous with the cam surface 236 and adapted to support the presser bar 66 against the force of the spring 228 upon movement of the presser bar lifter lever 232 in a counterclockwise direction to its limiting position. It will now be appreciated that the pressure exerted by the foot 222` against the material upon which the sewing machine is operated may be adjusted by varying the loading of the spring 228 by means of adjusting the screw 226. At its upper end the screw 226 is provided with a knob 240 adapted to be manually engaged for adjusting the screw 226.

Figures 5A and 5B illustrate a modification in which screw 226, rather than being threaded directly into a tapped opening in the frame member 44 as in the construction just described, is threaded into la sleeve 221 mounted in the frame member 44 and held against rotation relative thereto in any suitable manner. The sleeve 221 is normally held against upward movement, as viewed in Figure 5A by a iinger 223 on a lever 225 pivot- -ally mounted on the frame member 44 by a pin 227, the nger 223 projecting into a recess 229 extending transversely of the sleeve 221. ln the construction illustrated in Figures 5A and 5B, the sleeve 221 is held against rotation by Va projection 231 on the lever 225 which is received in a slot 232 extending longitudinallyV of the sleeve 221. The lever 225 also carries a spring 233 acting against the frame member 44 as illustrated in Figure 5A to urge the lever 225 in a clockwise direction as there viewed. It will be appreciated that by moving thelever 225 toward the knob 240 the linger will be withdrawn from the recess 229, thereby permitting the sleeve 221 to move upwardly in the frame member 44, releasing the spring pressure on the'presser foot 222, as is desired when the machine is to be used for darning. At such times the knob would also be moved to disengage the clutch collar 146 to stop operation of the material feeder mechanism 48. Upon completion of the darning the knob 240 may be pushed downwardly until the iinger 223 snaps into the recess 229, thereby automatically returning the parts to the desired position and establishing the same pressure on the presser foot 222 by the spring 22,8. It will now be appreciated that this enables darning to be done without changing the adjusted position of the screw 226 in the sleeve 221. y

Figure C shows the light supporting bracket 241 which is broken :away in Figure 5 to show `other details ofl the machine. The bracket 241 is formed of a flat strip the upper end of which is apertured to receive the screws 243 by means of which it is fastened to the outer end of frame member 44. The lower end portion of the bracket 241 extends outwardly at right angles, as illustrated at 245, to main portion of the bracket which is vertically disposed as illustrated in Figure 5C. A lamp' socket 247 is mounted in the horizontally extending portion 245 of the bracket 241 yand carries a suitable electric lamp bulb 249. Suitable wiring to the socket 247 is indicated at 251 and is supported on the frame member 44' as indicated at 253, independently of the end cover stamping' 58.

The upper frame member 44 :also carries `a suitable thread tension controlling mechanism generally indicated `at 242, which is best illustrated in Figures 1 and 5. This thread tensioning mechanism may be of any suitable conventional construction and in the preferred construction illustrated in Figure 5 is adjustable for varying the drag on the thread, In the construction illustrated, a sleeve 244 is fastened in the frame 44 by a pin 246, yand receives a shaft 248, the outer end of which is enlarged to form a head 250 and the inner end portion 252 of which is externally threaded for co-operation with a plate 254 which has Ian internally threaded aperture receiving the threaded portion 252 of the shaft 248. The plate 254 is held against rotation by a pin 256l mounted in the frame 44 and with which the plate 254 has a sliding engagement. A coil spring 258 surrounds the shaft 248 and is disposed between the plate 254 and the inner surface of the frame 44. Externally of the frame 44 a pair of. annular tension plates 260 and 262 and Aan annular cover plate'- 264 are mounted on the shaft 248 between the head 250 thereof and the outer surface of the frame 44. A piny 266. is mounted on the' sleeve 244 and extends outwardly through apertures in the tension plates 260 and 262 and the cover plate 264 to hold these plates against rotation.

A coil spring 268 surrounds the sleeve 244 and acts against the outer surface of the frame 44 at one end and against the inner surface of the tension plate 260 at its opposite end. It will not be appreciated that the loading of the spring 268 may be varied by rotating the shaft 244 to vary the loading of the spring 258. The sewing machine thread is passed between the two pressure plates 260 and 262 in the usual manner and it will now be appreciated that the loading of the spring 268, which controls the drag on the thread, may be varied by rotation of shaft 248 by grasping the head 250 thereof.

Referring to Figures 3 and 6 through l0, inclusive, the above mentioned material feed mechanism 48 mounted in the lower frame member 42 comprises a generally vertically disposed link 270 which is generally channel shaped, as best illustrated in Figure 6, and carries two vertically spaced pivot pins 272 and 274. The link 270 is'pivotally mounted on the frame member 42 by a pivot pin 272 extending through its long end and into a web portion 276 extending transversely of the lower frame member 42.- A pivot pin 274 at the upper end of the link 270 pivotally connects a first arm 278 to the link 270. This arm 278 extends generally horizontally and has its opposite end bifurcated to define a pair' of spaced opposed cam engaging surfaces 280 which receive therebetween a circular cam 282 xed on the shaft 132 in eccentric relation thereto. Intermediate its ends the arm 278 carries a material feeder jaw 284 xed to the upper portion thereof and adapted to engage the material upon which the sewing machine is operating for feeding the material. The plate 50 has an enlarged opening 286 therein (see Figure 3) disposed below the sewing machine head 60, Which is covered by a plate 288 fastened to the lower frame 42 by screws 290 (Figure I) and a second plate 292 which is hingedly connected to the plate 288 by a pair of pins 29`3 and may readily be pivoted upwardly and removed to the right, as viewed in Figures ll and 3, about this pivotal connection, permitting access to the bobbin from above. The plate 288 has an aperture 294 through which the needle 84 is moved during the sewing operation and a pair of apertures 296 and 298 at opposite sides of the needle 184 through which the material feeder jaw 284 may move for engaging the material during operation of the sewing machine.

The central portion of the arm 278 is formed to provide an enlarged opening 380 through which the shaft 112 extends, the opening 300 being of suihcient size to prevent interference of the shaft 112 with movement of the arm 278 during operation of the material feeder mechanism 48.

Intermediate the pivot pins 272 and 274,y one end of a second arm 302 is pivotally connected to lthe link 270 by a pivot pin 304. Adjacent its opposite end the arm 302 has a pair of spaced opposed cam surfaces 306 Which receive therebetween a circular cam 308 which, in the preferred embodiment illustrated, is formed integral with the above described circular cam 282. Intermediatei-fs ends the central portion of the arm 392 is also formed to defined an enlarged opening 310 proportioned to receive the shaft 112 and prevent interference thereof with the movement of the arm 382 during operation of the material feeder mechanism 48. Adjacent the cam surfaces 306, and upwardly therefrom, as best illustrated in Figure 9', the arm 362 carries a pin 312 which extends laterally from' the arm 362 and projects into a slot 314 formed in a' disk 316 mounted in an enlarged portion 318 of the web 276, for rotation about a horizontal axis. Movement of the disk 316 is effected by means of a shaft 320 (see Figure 3) which, in the preferred embodiment there illustrated, is coaxial with a stub shaft 322 formed integrally with theY disk 316 in coaxial relation thereto. The shaft 320 is connected to the stub shaft 322 lby a coupling sleeve 324 receiving adjacent ends of the shafts 322 and 320. The opposite end of the shaft 320 is journaled in a web' portion 326 extending transversely of the lower frame 42. The shaft 32) carries a crank 328 (see Figures 2 and 4) fixed thereto which is connected by a generally vertically extending link 330, to a lever 332 one end of which is pivotally connected to the frame 44 by a pin 334 and the opposite end of which has al tapped opening 336 extending longitudinally inwardly thereof. Movement of the lever 332 is effected by a -screw 338 threadedly received in the tapped opening 336 and extending outwardly through a vertically extending slot 340 in the plate 174, and provided with a knob 342 at its outer en'd.

It will be appreciated from a consideration of the above described structure that when the clutch collar 146 is disposed in the engaged position illustrated in Figure 3 to operatively connect `the gear 136 to the shaft 132, rotation of the shaft 132 will eiect vertical movement of the material feeder jaw 284 by virtue of the engagement of the eccentric cam 282 with the cam surfaces 280 on the arm 278, and -that horizontal movement of the jaw 28'4 will be lsimultaneously effected, when the disk 316 is in the position illustrated in Figures 7, 8 and 9 by virtue of the movement of the pin 312 along the slot 314 pursuant to the co-operating engagement of the cam 368 and the camengaging surfaces 306. This movement of the pin 312 in the slot 314 will eifect pivotal movement of the link 270 about the pivot pin 272 and thereby produces generally horizontal movement of the arm 278. It will also be appreciated that by rotating the disk 316 through movement of the knob 342 between the positions illustrated -in Figures 9 andv l0', the horizontal movement of the jaw 284 may be varied from a maximum in one direction throughV zero to a maximum in the reverse direction. The threaded engagement of the screw 338 with the lever 332 permits the lever 332 to be adjusted for a given stitch length and the screw 3-38 to be threaded into the opening 336 until the knob 342 engages the plate 174. With this condition of adjustment the knob 342 may be moved to the reverse position and returned to the forward position with the knowledge that it will return to the same position and afford the same stitch length as the position which it occupied prior to movement to the reverse position. The forward position of the stitch control knob 342, in which the material is fed from the front of the machine to the rear, is illustrated in Figure 10, the direction of feed being from right to left as there viewed.

In the preferred embodiment illustrated, the eccentric circular cams 282 and 308 are angularly spaced relative to one another through an angle of 90. This angular spacing of the cams 282 and 308 has been found to effect the movement of the material feeder jaw 284 along a curvilinear path providing a maximum horizontal movement of the jaw 284 while the latter extends above the plate 288, for a minimum of vertical movement of the jaw 284 while the latter projects above the plate 288. It will be appreciated that maximum feed from front to rear is obtained with the control knob 342 at its lower limit and maximum feed in the reverse direction is obtained with the knob 342 at its upper limit, lthe knob 342 passing through a zero feed position intermediate these limits.

The above mentioned shuttle 46 is fastened to the outer or left hand end of the shaft 112, as viewed in Figures 3 and 6, and carries a bobbin 344 which carries the lower thread employed in lock stitch type sewing machines. In the preferred embodiment illustrated in Figures 1 through l0, inclusive, the shuttle 46 is driven in timed relation to the movement of the needle bar 62 by the above described drive means and the shuttle 46 completes two revolutions for each cycle of reciprocatory movement of the needle bar 62, and the shuttle mechanism 46 picks up the upper thread carried by the needle 184 and forms a stitch in the manner conventional with machines of this type.

Referring to Figure 1, in the preferred embodiment there illustrated, the spool of thread 346 is carried in a bracket 348 mounted on the front shell stamping 54 above the thread tension control 242 and to the left of the lever 68 which provides and takes up the slack in the upper thread. From the spool 346 the thread extends downwardly and is trained about the thread tension control 242 from which it passes upwardly through the eye 206 in the outer end of the lever 68 and thence downwardly through a pigtail guide 350 at the lower right hand portion of the head 68 as viewed in Figure 1. lt then extends downwardly through another guide 352 on the needle bar 62 below which it is threaded through the eye of the needle 184.

Referring to Figures 1 and 1A, it will be noted that the bracket 348 is disposed to support the spool of thread 346 with its axis extending horizontally. The bracket 348 includes a portion extending outwardly from the shell stamping 54 and carrying a spindle 345 extending horizontally to the left therefrom. To prevent inadvertent movement of the spool 346 from the spindle 345, a spool retainer 347 is mounted in the spindle 345 and comprises a hollow shaft 349 having a slotted inner end portion 351 proportioned to frictionally grip the spindle 345. At the opposite end of the shaft 349 is a handle 353 which is of larger diameter than'the shaft 349, thereby providing an annular shoulder 355 adapted to engage the outer end ofthe spool 346 to limit movement thereof outwardly of the spindle 345.

It is an important feature of the present invention that the complete design of the machine has been carefully worked out so that the needle is threaded from the right with the light at the left of the needle, thereby greatly facilitating the threading operation.

The sewing machine 40 has an electric terminal block 354 mounted on the lower portion of the upper frame 44 at the back thereof, or the right hand side thereof as viewed in Figure 2, adapted to receive ythe plug 356 of a cord 358. The terminal block 354 is electrically con- 12 nected to the motor 104, by suitable wiring (not shown). A conventional rheostat control is provided for controlling the speed of the motor 164 as desired. The lamp socket 247 is connected to the terminal block 354 by the wiring represented in part at 251, through a switch 360 mounted in the plate 174.

The sewing machine 4i) also includes improved means for the winding of bobbins, comprising a mounting plate 362 fastened to the inner surface of the front shell stamping 54 by screws 364 at the right hand end of the machine 4t?, as viewed in Figure l. (See Figures 2 and 11.) A stamping 366 is secured to the mounting plate 362 by a bolt 368 and is disposed externally of the shell 54. The stamping 366 extends generally at right angles to the adjacent portion of the shell 54 and has an aperture 370, the purpose of which will be presently described. The bobbin winding mechanism also includes an arm 372 pivotally mounted on the plate 362 by means 0f a bolt 374. At its outer end the arm 372 carries a pin or rivet 376 rotatably supporting a bobbin drive wheel 378 including an outer annular rubber ring 330 adapted to project through the opening 370 in the bracket 366 and engage the flywheel 84. The wheel 378 also has an integral coaxial hub portion 382 adapted to receive the bobbin indicated in broken lines at 384. An annular ring 386 is mounted on the rivet 376 between the arm 372 and the wheel 378. A pin 388 is mounted in the wheel 378 and extends axially outwardly to project into the aperture conventionally provided in the bobbin 384, as illustrated in Figure 11. The outer portion of the stamping 366 adjacent the aperture 370, which is indicated at 390 is deformed as illustrated in Figure 2 to provide a portion adapted to project between the spaced flanges of the bobbin 384. it will be appreciated that with the bobbin mounted on the hub 382 in the position illustrated in Figure il, it will be held against movement axially downwardly as there illustrated, by the deformed portion 390 of the stamping 366 when the arm 372 is pivoted upwardly to move the rubber ring 38@ of the wheel 378 into engagement with the flywheel 84. lt will also be appreciated that when the winding of the bobbin has progressed to the desired extent, the thread wound upon the bobbin will engage the portion 390 of the stamping 366 and eventually pivot the arm 372 in a counterclockwise direction, as viewed in Figure 2 to move the wheel 378 out of engagement with the flywheel S4 at the time when the winding of the bobbin 344 is completed.

It will be appreciated that the above described construc- -tion provides an efficient, compact bobbin winding mechanism. The thread for winding the bobbin may come from a spool (not shown) mounted on a spool support 392 extending vertically upward from the right rear corner from the plate 5G as viewed in Figure l. A thread guide 394 is provided at the front right hand corner of the plate 5t? over which the thread from the spool holder 392 may be trained and from which it may be trained over the bobbin 384. The provision of the spool support 392 for use in the winding of bobbins eliminates the need for using thread from the spool 346 mounted in the bracket 348 permitting the operator to leave the upper thread of the sewing machine in place, thereby eliminating the need for rethreading the upper thread after the bobbin is wound.

The applicants improved sewing machine 40 also incorporates improved means for lubricating the head mechanism. Referring to Figures 3A and 3B, the upper frame member 44 is formed to define an oil well 396 disposed adjacent the bearing supporting the left end of the shaft 74 as viewed in Figure 3.

The upper frame member 44 also defines an oil charnber 398 surrounding the shaft 74 at the iight hand end of the bearing 70. This chamber 398 communicates with the oil well 396 and both the chamber 398 and the well 396 are lled with a porous material or wick 469. The

13 shaft 74, which rotates in av countercloclwise direction as viewed in Figure 3B, has a groove 402Y formedV in its outer surface within the length of the bearing 70 which is inclined as illustrated in Figure 3A, so that upon rotation of the shaft 74, oil collecting in theV groove 402 is forced to the left hand end thereof. At its left hand end the groove 402 communicates with a generally radially extending opening 494 communicating at its inner end with a centrally disposed longitudinally extending passage 496 which is drilled in the outer end of the shaft 74 and closed by a plug 498. Adjacent its outer end the passage 496 communicates with a radially extending passage 410 opening through the outer surface of the shaft 74 and communicating with a passage 412 formed in the hub member 21S and which in turn communicates with a radially extending passage 414 formed in the crank 216 which has a horizontally extending passage 416 closed by a plug 418 and communicating with the passage 414. The crank 216 also has a second passage 420 communieating with and extending at right angles with the passage 416 which is similarly closed by a plug 422 and communicates with a lubricating passage 424 formed in the pin 19S and connecting with a radially extending passage 425 opening through the bearing surface of the pin 198. Also, the link 212 preferably includes a passage (not shown) through which oil supplied to the surface of the pin 19S may pass to the recess 202 to lubricate connection lof the needle bar pin 188 with the link 212. It will now be appreciated that to eiect lubrication. of the head mechanism it is necessary only to ll thewell 396 with oil which is held by the wick material 400. Oil from the wick portion disposed within the oil chamber 398 is carried along the shaft 74 where it collects in the groove 402 and the rotation of the shaft effects a pumping of the oil from the groove 402 through the passages 404, 406, 410, 412, 414, 416, 420, 424 and 425 to the bearing surface of the pin 19S, and thence to the recess 202. Lubrication of the pivotal connection of the inner end of the lever 68 to the crank 216 is provided by a radially extending passage 426 formed in the crank 216 and communicating with the passage 416.

The bearing 72 adjacent the right hand end of the shaft 74, as viewed in Figure 3, is also lubricated by oil carried in a wick 580 received in an oil chamber S82 provided in the upper frame member 44 (see Figure 2). It will be appreciated that the oil chamber 582 opens through the bearing 72 so that the wick 530 bears against and supplies oil to the shaft 74.

The transversely extending web 276 of the lower frame member 42 also has an oil chamber 584 extendinghorizontally and disposed as illustrated in Figures 3 and 5, to open through bearings 114 and 134 supported inthis transversely extending web so that a wick 536 disposed within the chamber 584 may bear against and lubricate the shafts 112 and 134.

Similarly, an oil chamber 58S is provided in the lower frame member 42 .for lubricating the bearings 116 and 136 and is disposed as illustrated in Figures 2 and 5 so that a wick 590 in the chamber 588 bears against and lubricates the shafts 112 and 132. The chambers 584 and 588 are closed by plugs 592 and 594 respectively, threadedly mounted in the outer ends thereof, and oil is supplied to the wicks 586 and 590 through small passages 596 and 598 respectively (see Figures 2 and 3) extending upwardly therefrom and accessible through cooperating apertures 600 and 602 respectively, provided in the plate 50 (see Figure l).

The above described lubrication of the various bearings of the sewing machine by means of oil chambers and wick permits the initial lubrication of the machine to be sufficient and effective for periods of several years in the normal use of the machine.

It will be appreciated the above described sewing machine may be mounted in a supporting cabinet with the 'upper surface of the plate 50 substantially hush with 14V the adjacent worl'rv supportingV surface of the cabinet,- b` any suitable means such for example asA that indicated generally at 610 in Figure 2'. The above described sewing; machine 40 is also peculiarly adapted for. use as a. portable machine because of the fact that. its improved design permits it to be constructed of lightweight materials and stillv have materially less vibration than con.- ventional machines even when operating at higher. speeds than such machines. Thus the above described machine weighs substantially less than conventional' machines of corresponding size, which is obviously animportant factor in portable machines.

Figures 32, 33 and 34 illustrate a sewingv machine 40 including improved features facilitating its use as a porta'- ble machine. The machinev illustrated in theseV figures is provided with aps 620 which, in the construction illustrated, are rectangular in shape. These flaps, in the position illustrated in Figure 32 provide ramps at the front and rear ofthe machine sloping upwardly from the table top -or other surface uponv which the machine is supported, to the upper surface of the plate 50, and along which the material upon which the machine is operating, may move toward and from the presser foot 222; It will be appreciated that the aps 620 may be connected in the position illustrated in Figure 32Vv by any suitable means. Preferably,y this connection is such that the iiaps 626 maybe pivoted from the position illustrated in Figure 32 to the positions illustrated in Figures 3'3 and' 34. In the construction illustrated, this connection is eifected by the three hingesV 622 which are* generally Z-shaped as best illustrated in Figures 32` and 33 to'prevent interference of theaps' 620 with they edge portions of the plate 50 which overhang the lower frame member 42. i

In the positions illustrated' in Figures 33 and 34, the aps 620 provide protection for' the machine and may' also bel provided with suitable apertures for connection. of a handle 624` thereto by means of suitable snap fasteners indicated' at 626. With this' construction a separate carrying case-isY not required and the machine may be covered only by a soft bag for dust protection. It will be appreciated, ofcourse, that flaps may be used' equally well when the'machine is mounted in the base -or lower portion of a carrying case (not shown).

The improvements ofthe present invention may also be embodied in a wide variety of sewing' machines of various types diifering' from the sewing machine 40 illus'- trated in Figures l to 11, inclusive', wherein a rotary shuttle is employed which completes two revolutions for each` complete reciproc'ati'on of the needle bar. Figures 12 and 13 illustrate, somewhat' digrammatically, one way in which certain of the improvements ofthe present invention maybe embodiedi inY a sewingV machine of the type wherein ythe shuttle is mounted for rotation about a vertical axis and completes one revolution foreach complete reciprocation of the needle bar. In the construction there illustrated, the upper frame member 44 carries the same general mechanism as tha-t described in connection with the sewing machine 40 with rtheV exception that the diameter of the pulley' wheel 80 isi substantially less than that ofthey pulley wheel and the belt 178 is materially longer than. the belt178 and is trained over a pair of idler wheels 428 mounted in the lower frame 42 for rotation about a horizontal. axis. The belt 17 S also includes a horizontally disposedportionexitending longitudinally of. the lower frame 42 and which is trained over a pulley wheelV 430 of. the same diameter as the wheel 80' and mountedA for rotation about a vertical axis on a shaft 432 journaled in a gear box 434A suitably supported on the lower frame 42. Within the gear box 434 are a pair of similarme'shing eccentric gears 436` and 43S, the former of which is fastened' to the shaft 432' for rotation with the pulley wheel 430 andthe latter'ofiwhich is fastened to a secondv vertically disposed shaft' 440 journaled in ther gear box 434 in` spacedrelation tothe" shaft 432. The shaft 440 extends upwardly beyond the gear box 434 and carries a shuttle 442. The eccentric gears 436 and 438 are shaped to provide a desired predetermined variation in the speed of angular movement of the shuttle 442 during each revolution thereof which is conventional in sewing machines of the type in which the shuttle completes a single revolution for a single complete reciprocationV of the needle bar mechanism. As in the case of the sewing machine 40, the pulley belt 178 is formed to provide a positive engagement with the wheels 80' and 430, thereby insuring the driving of the wheel 430 in accurate timed relation to the wheel 80.

Figures 14 and 15 illustrate, also somewhat diagrammatically, one manner of embodying certain of the improvements of the present invention in a sewing machine of the type having a shuttle mounted on the end of a pivotally supported arm and in which the shuttle oscillates back and forth on the arc of a circle. In the construction there illustrated, the belt 178 is similarly trained over idler wheels 428 and drives the wheel 430 mounted on a shaft 444 for rotation about a vertical axis. An arm 446 is pivotally mounted on a vertically disposed pivot pin 448 and has one end bifurcated to deine a slot 450 which receives a crank pin 452 mounted eccentrically on the Wheel 430. A shuttle 454, which may be of conventional construction, is mounted on the opposite end of the arm 446. It will now be appreciated that as the Wheel 430 rotates, the arm 446V is oscillated about the pin 448 by the co-operation of the crank pin 452 moving in the slot 450, to move the shuttle 454 back and forth along the arc of a circle whose center is the axis of the pin 448.

Figures 16, 17 and 18 illustrate in somewhat diagrammatic fashion one form which the present invention may take when certain of the improvements thereof are embodied in a sewing machine of the type having a shuttle which rotates about a horizontal axis and completes a single rotation for each complete reciprocation of the needle bar. In the construction there illustrated, the upper wheel 80 is of the same diameter as the lower Wheel 122 and is operatively connected thereto by the belt 178, the lower Wheel 122 completing one rotation for each rotation of the upper wheel 80. The lower wheel 122 is fixed on a stub shaft 456 journaled in a bearing 458 at the righthand end of the lower frame 42, as viewed in Figure 16, and the wheel 122 co-operates with a lock collar 460 fastened on the outer end of the shaft 456 to prevent axial movement of the shaft 456. The shaft 112 carries the shuttle 46 on its left end as ,viewed in Figure 16 and at the right end carries a disk 462, the outer or right hand axial face of which has, a diametrically extending slot 464 (Figure 17) which receives the outer end of a pin 466 mounted eccentrically on the wheel 122. The shaft 456 is disposed parallel to the shaft 112 with its axis spaced slightly from the axis of the shaft 112'. It will be appreciated that this construction produces a predetermined variation in the velocity of angular movement of the shuttle 46 during each revolution thereof as is conventional in machines of this type in which the shuttle completes a single revolution for each complete reciprocation of the needle bar.

Figure 19 illustrates a modication of the construction .illustrated in Figures 16, 17 and 18 in which the variation in the velocity of angular'movement of the shaft 112 which carries the shuttle, is eifected by the engagement of a pair of meshing eccentric gears 468 and 470 mounted, respectively, on the shafts 456 and 112 in place of the pin and slot drive there illustrated. It will be appreciated that in the construction illustrated in Figure 19, the shaft 456 is spaced a substantial distance from the shaft 112 permitting meshing engagement of the gears 468 and 470 fixed, respectively, to the shafts 456 and 11,2. The construction illustrated in Figure 19 also demonstrates Vthat if desired the motor 104 may, in any of the various forms of machines, be mounted with the driving wheel v16 110 of the motor directly engaging the belt 178 rather than directly engaging the flywheel 84.

Figures 21, 22, 23 and 24 illustrate modifications showing the improvements of the present invention incorporated in sewing machines of the type in which the shuttle oscillates about its own axis in the stitch forming process. In the construction illustrated in Figures 2l and 22 and in the construction illustrated in Figures 23 and 24, the shuttle 46 is xed on a coaxial shaft 112' and is oscillated through the desired predetermined angular movements by the hereinafter describedY mechanisms. Referring to Figures 2l and 22, the lower pulley wheel 122 is driven by the belt 17S in timed relation with the upper pulley wheel (not shown) and makes one complete revolution for each complete revolution of the upper pulley wheel. The lower Wheel 122 is rotatably mounted on a stub shaft 472 xed in the lower frame 42 at the right hand end thereof as viewed in Figure 2l. The wheel 122 carries a crankpin 47 4 mounted eccentrically thereof, the outer end portion of which is journaled in a sliding block 476 received in and slidably fitting a channel 478 in one face of an arm 489 pivotally mounted on the lower frame 42 by means of a pivot pin 482. in the opposite face of the arm 480 is a second channel 484 which receives a sliding block 486 journalling a crankpin 488 on the outer end of a crank 49@ fastened to the shaft 112. The two channels 478 and 484 extend radially outwardly from the pivot pin 482 in the same direction and the stub shaft 472 upon which the lower pulley wheel 122 is mounted is disposed in parallel relation to the shaft 112' with its axis spaced slightly from the axis of the shaft 112. From a consideration of the above described construction, it will be appreciated that the rotary movement of the lower pulley wheel 122 may be converted 'to an oscillatory angular movement of the arm 48% through a given angle and which in turn effects an oscillatory movement of the shaft 112.', together with the bobbin 45 carried thereby, through a predetermined larger angle. In the construction illustrated, rotary movement of the loWer pulley wheel i122 produces oscillatory movement of the arm 48@ through an angle of approximately and this movement of the arm 480 in turn produces oscillatory movement of the shaft 112 through an angle of approximately 210.

Referring to Figures 23 and 24, the construction there illustrated differs from that shown in Figures 21 and 22 in that the arm 481) is replaced by an arm 492 pivotally supported on a pin 494 and the opposite ends of which are bifurcated to deline slots 496 and 498 which are disposed at opposite sides of the pivot pin V494 in diametrically opposed relationship and perform the functions of the channels 47S and 486. It will be noted that in this construction the shafts 472 and 112 are spaced a substantial distance from one another in contrast to the relatively slight spacing between the shafts in the construction illustrated in Figures 2l and 22. As in the construction described in Figures 2l and 22, the construction illustrated in Figures 23 and 24 converts rotary movement of the lower wheel 122 into oscillatory movement of the arm 492 through an angle of approximately 90 which movement in turn produces oscillatory movement of the shaft 112 through an angular movement of approximately 210.

Figure 20 illustrates a chain stitch type sewing machine embodying the improvements of the present invention. In the construction there illustrated, the lower frame member 42 has a greater depth than the frame member 42 of the above described machine 4t?, and carries the motor 1434 and a short shaft 5430 which is journaled in a bearing 562 and extends outwardly through the frame member 42'. Externally of the frame member 42', the shaft 500 carries the ywheel 84 fixed thereto and the lower pulley wheel 122 is fixed on the shaft Sith inwardly of the bearing 5192. The tapered driving wheel on the output shaft of the motor iti-4 directly engages the iiymaar wheel 84.. Iheupperpulley-Wheel 80 is; of the same diameter as the lower wheel12'2, and is driving'ly c0121,-` nected thereto by the belt 178 for rotation in timed relation thereto, the upper pulley wheel 80 completing one revolution for each revolution of `the lower. wheel 122. The upper pulley Wheel 80 may be operatively connected to the needle bar 62v by any suitable mechanism such, for example, as that embodied in the sewing'machine 4G illustrated in Figures l to ll, inclusive, and described above. A shaft 112 is rotatably supported Within the lower frame 42' and carries at the left hand end thereof a hook 504 of conventionl construction. In the construction illustrated in Figure 20, the shaft 590 is disposed in spaced parallel relation to the shaft 112 and is operatively connected thereto by a mechanism similar to that illustrated in Figures 16, 17 and 18 to effect desired variations in the angular velocity of the shaft 112 during each revolution thereof. This mechanism includes a pin 446 mounted eccentrically in the wheel 122 and the outer end of which is received in a slot 464 provided in a disk 462 xed on the right hand end of the shaft 112.

Figures 25, 26 and 27 show a modified head mechanism including means providing dynamic balancing and may be employed when it is desired to keep vibration to an absolute minimum. The elements corresponding to the similar elements in the above described head mechanism 69, illustrated in Figure 3, have been given the, same reference characters.

Referring to Figures 25, 26 and 27, the. shaft 74 extends beyond the bearing 70' in the upper frame member 44 and carries a plate 510 securedy thereto. The frame member 44 also supports a bearingl 512 outwardly of and aligned with the bearing 70 in which is journaled a short shaft 514 disposed in coaxial relation with the shaft 74. Inwardly of the bearing 512 a second plate 516 is secured to the inner end of the shaft 514. Intermediate the plates 510 and'516, and in spaced relation to each, is a third plate 518V whichV is disposed in concentric relation with the plates 510 and 516. The plate 510 is connected to the plate 518 by a pin 520 extending at right angles to th'e plates and having its opposite ends fastened thereto as by the set'screws 5,22 and 524. The pin 520 is disposed eccentrically of and adjacent the periphery of the plates 510 and 518gand provides a driving connection between the plates 510 `and 5.18,. At a point diametrically opposite the connection ofthe pin 520 to the plate 518, a second pin 526 interconnects the plate 518 to the plate 516'in the same mannerasV the pin 520 interconnects the plates 510 and 518. In this modied construction the inner' end ofthe lever 68 is pivotally connected to the pinv 526.A To dynamicallybalance the eccentrically moving mass of the lever 68, and the link 210, another lever 528 is disposed between the plates 510 and 518 andhas one end vpivotally connected to a pin 530 mounted onV the frame member diametn'cally opposed relation to the pin 214. A weight 532 is xed to the opposite end of the lever-'528 and -is'ofa mass such that upon operation of the mechanisrnpthe lever 528 and mass 532V dynamically balance the lever 68. It will be appreciated that the weight 532 to permit a foreshortening of the lever v528 as compared with the lever 68. Intermediate its ends the lever 528 is pivotally connected to a link S34, the opposite end of which is apertured to receive the pin 520. It will now be appreciated that in the above described construction the lever S28 moves similarly to but at all times opposite to the movement of the lever 68. This is illustrated in Figures 26 and 27.

Outwardly of the bearing 512 the shaft 514 carries an eccentric cam S36 (see Figure 30) which is engaged at the top and bottom thereof by a rectangular frame 538 mounted for vertical rectilinear movement on a pair of spaced guide rods 540 supported in the frame member 44. A weight 542 adapted to dynamically balance the needle bar 62 is fastened to the frame 538 and moves vertically 18 therewith within. a recess 544` provided in Vthe frame 44. The eccentric 5136 is circular and is fastened to the shaft 514'to provide movement of the weight 542vwith a velocity and acceleration opposite to that of the needle barr62. and suticient to dynamically balance the latter.

i In the construction illustrated in Figure 25, the pin 198 carrying the pinion gear 209 is mounted directly in and eccentrically of a driving member 548 fastened to the outer end of the shaft 514 and corresponding to the hub member 218 of theabove described head mechanism 60. The drive member 5.48 is formed to provide an integral mass eccentric of the shaft 514, and whichV is illustrated in Figure 25 at the upper sideof the shaft 514, which is proportioned to counterbalance the pinion gear 200, the link 212, thepin 198, as Well as the diametrically opposed portion of the drive member 548 in which the pin 198 is mounted. Y

It will thus be appreciated that in the head mechanism illustrated in Figures 25, 26 and 27, the eccentric mass of the lever 68, and the link 2.1 0 iscounterbalanced by the lever 528v and link 534, and that the needle bar 62 is counterbalanced by theweight 542. Also, the pinion gear 200, the crank link21-2, and the pin 198 are counterbalanced by the integrally formed counterbalance weight portion of the drive member 548.

Figures 28, 29 and 30 illustrate a modified construction including the same means for counterbalancing the needle bar 62k andthe pinion gear 200,v` together with its crank link 212 andsupporting pin 1978, as that shown in Figure 25,.and in which the leverV 68 for providing and taking up the slack in the thread is replaced by a modified lever 68. In this construction the shaft 74 extends through theV bearing 701and carries the, drive member 548 at its outer end. Intermediate the drive member 548 andthe bearing 79, the shaft 74 carries a cam 550xed thereto for rotation therewithand adapted to engage a suitable cam follower 552 mounted on the lever 68. The lever 685 is pivotally supported at'its inner end on the upper frame member 4,4aud is urged in a clockwisedirection as viewed in Figure 29 by a .spring 554 which holds the cam follower 552in engagement with the cam 550.l The cam 550 is shaped to provide the desired movementof the lever 68,. The lever 68Al and cam 550 are counterbalanced by another lever 556 pivotally mounted on the upper frame member 44- in diametrically opposed relation `to the lever ,685 and carrying a cam Vfollower 558 which is maintained against a cam 560 by a second spring` 562. The cam- 560 is identicalwith the cam A55() and angularly spaced therefrom through an angle of It will be appreciated that the lever- 556 is moved with` a velocity and acceleration equal and oppositeto thatof the lever 68. The arm 556 is foreshortened ascompared to the arm 68 and at its outerendthe arm 55,6 carries a weight 564 compensating for this. The shapes of the cams 550 and 560 are illustrative only'. Itwill beappreciated, of course, that the rollers 552 'and 558. couldV engage their respective cams in cofoperating grooves soias to eliminate springs 554 and 562.

Figure 3l illustrates, a modified construction in which the. counterbalance lever 556-is omitted and in which a mass 5661 is mounted eccentrically on the shaft 74 and angularly spaced from the lever 68 and proportioned to substantially counterbalance the lever 68.

While only several specific embodiments of the invention have been illustrated and described in detail, it will be readily appreciated by those skilled in the art that numerous modifications and changes may be made without departing from the spirit of the present invention.

What is claimed is:

l. In a sewing machine having a frame, a drive shaft rotatably mounted in said frame, a crank mounted on said drive shaft for rotation with said drive shaft, a crank pin on said crank parallel to said drive shaft, a pinion gear mounted on said crank pin for rotation relative thereto, a link fixed to said pinion for rotation with said

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