US3500875A - Shuttleless loom tension pad stop motion - Google Patents

Description

March 17, 1970 J. E. BROWN 3,500,875

SHUTTLELESS L00! TENSION PAD STOP MOTION Filed 0013. 17, 1967 4 Sheets-Sheet 1 IN VEN TOR.

IJ Z PTEBHoW/ TOR/KEYS March 17, 1970 J. E. BROWN SHUTTLELESS LOOM TENSION PAD STOP MOTION 4 Sheets-Sheet 2 Filed Oct. 17, 1967 J. E. BROWN March 17,1970

' SHUTTLELESS LOOM TENSION PAD STOP MOTION 4 Sheets-Sheet 3 Filed Oct. 17, 1967 INVENTOR. tJE'PrEBRoW/V BY MM @VZ/Zuq 19 7 0/?5 Y5 J. E. BRQWN March 17, 1970 SHUTTLELESS LOOM TENSION PAD STOP MOTION 4 Sheets-Sheet 4 Filed 001:. 17, 1967 INVENTOR. fEBfidW/V BY J flTfOR/VEYS United States Patent U.S. Cl. 139-336 8 Claims ABSTRACT OF THE DISCLOSURE A tension pad stop motion for weaving looms of the shuttleless type wherein a receiving carrier has mounted thereon a resilient tension pad, comprising an electrode secured to and insulated from the receiving carrier guide in such a manner as to provide a substantial length of contact area spaced from said tension pad, when under normal operating conditions and parallel to the path of travel of said receiving carrier, and means electrically connecting the electrode to the electrically controlled stop motion apparatus for the loom whereby a sprung tension pad will contact the electrode to complete a circuit through the electrode to ground, which action will activate the stop motion apparatus to knock off the loom.

This invention pertains to stop motions for weaving looms and more specifically concerns tension pad stop motions for looms of the shuttleless type.

In shuttleless looms, that is, those looms in which filling is supplied from an outside source and not carried to and fro through the shed by the shuttle or carrier itself,

each pick of filling is inserted by two reciprocating elements, one of which is hereinafter referred to as a transmitting or inserting carrier and the other of which receives or has transferred to it, the loop of filling projected into the shed by the transmitting carrier, and which is hereinafter referred to as the receiving carrier. The latter member is normally provided with a hooked element by which the filling is seized and trapped and through which or past which, the filling may move end-wise so that the action of the carrier to which the said inserted loop is transferred, is one of merely drawing through, or extending an end which will have been severed to the precise length to complete the pick.

In order to retain the loop on the receiving carrier and to provide the proper tension in the filling, a tension pad is generally secured to the receiving carrier and functions to exert pressure on the inserted loop to regulate the force required for the end-wise withdrawal of the filling from the carrier. The tension pad is usually made from metallic material in leaf spring form, one end of which is fixedly positioned at approximately the center of the carrier with the leading end spring biased towards the forward section of the main body and the hooked element of said carrier, thus forming those elements which trap, tension and guide the inserted loop of filling as it is being extended. A more detailed description and explanation of such tension pads may be had by reference to U.S. Patents 2,705,508 and 3,034,539.

In looms of the type described above, should the carriers become misaligned for one reason or another, a collision between the carriers will occur at the center of the shed. A sprung tension pad is often the result of such a collison. That is to say, the collision of the transmitting carrier with the receiving carrier will force the leading end of the spring biased tension pad away from the forward section of the main body portion and hooked element of the receiving carrier to a point beyond its elastic limit, thus resulting in a permanent deformation 3,500,875 Patented Mar. 17, 1970 or deflection of the tension pad. During the withdrawal of the receiving carrier no detrimental effects are experienced due to the sprung tension pad, however, should the loom continue operation after such a collision, upon reinsertion of the receiving carrier into the shed on the next pick cycle, the sprung tension pad will engage the warp threads and act as a knife-edge to cause a break-out. Due to the speed of such looms, these break-outs will be quite large and in many instances, damage to the tape and carrier, beyond repair, will occur.

The present invention provides apparatus which may be readily incorporated into existing shuttleless type looms for detecting the existence of a sprung tension pad as the receiving carrier is withdrawn from the shed and for knocking oil the loom before the receiving carrier is again reciprocated into the shed on the next pick cycle.

In accordance with the present invention, an electrode is disposed adjacent the path of the receiving carrier in such a manner that during normal operation no contact between the electrode and the carrier occurs. However, should the tension pad be sprung out of engagement with the carrier, contact will be made between the tension pad and the electrode. The electrode is suitably connected into the electrically controlled stop mechanism of the loom whereby the contacting of the grounded tension pad with the electrode will result in the knocking off of the loom to thereby prevent any damage which would otherwise be caused by the sprung tension pad.

The present invention may be more fully understood by referring to the detailed description and drawings wherein:

FIGURE 1 is a front elevation of a shuttle loom to which the invention has been applied;

FIGURE 2 illustrates the receiving and transmitting carriers employed in the loom shown in FIGURE 1;

FIGURE 3 is an exploded view of the receiving carrier guide illustrating the connection of the electrode thereto;

FIGURE 4 is a perspective view of the receiving carrier guide with the electrode connected thereto and the receiving carrier disposed therein;

FIGURE 5 is an end view of the apparatus shown in FIGURE 4;

FIGURE 6 is a schematic illustration of the electrical control circuit for the loom knock off apparatus;

FIGURE 7 is a perspective of the suitable power transmission apparatus for use on a loom shown in FIGURE 1 along with a clutch-break control mechanism; and

FIGURE 8 is a blown-up view of the spring-biased clutch lever connection shown in FIGURE 7.

With reference to FIGURE 1, enough of a loom of the type described is shown to convey an idea of the relative arrangement of the parts involved and the details of certain of the parts particularly relevant to the improvements with which this invention is concerned. The loom is built upon a framework comprising loomsides 10 and 11, girst 12 and a breast beam 13. A top motion generally indicated by numeral 14 is shown as being supported upon an arch 15 in more or less the conventional fashion and serving to control harness frames such as that at 16 in cooperation with a harness cam mechanism (not shown).

At each end of the loom frame are supported, in a casing 17 at one side and 18 at the opposite side, tape wheels, one of which is illustrated at 19. Supporting structure including the braces or brackets 20 and 21 serves to retain these casings and the tape wheel mountings in proper relative relationship to the other parts so that the tape wheels may be oscillated to and fro about axes such as the axis 22. The wheel 19 is inter-connected for movement by an eccentric mechanism 23, carried at the end of a shaft 24 which is rotated in synchronism with other parts of the loom and which is positively driven through suit- )le gearing means (not shown) by a suitable source of Jwer such as motor 25. The motor is provided with a nventional break-clutch mechanism which is adapted be operated by shipper levers 26. Eccentric mechanism t is similarly provided on shaft 24 at the left side of the om to provide the oscillatory drive for the tape wheel cated in casing 17.

The tape Wheels have affixed thereto tapes, one of which indicated at 30 and the other of which is indicated by imeral 31. Tape 30 carries a head or a transmitting carer member 32, as shown in FIGURE 2. Head 32 is lapted to engage and to project into the shed of the tbric, a double length of filling, one end thereof being :ld in a binder or retaining element, the filling actually :ing drawn from the source of supply S at that time. he other tape 31 has fixed at the free end thereof, a :ceiving carrier member 33 which is formed as shown FIGURE 2 and which is adapted to receive the filling om the transmitting carrier as they inter-engage or go trough a transferring function at a point adjacent the :nter of the loom, or adjacent the center of the fabric :ing woven, and then upon release of the free end of Lid filling, extend that end over to the opposite end of 1e fabric in a manner understood by those conversant ith the operation of looms of this general description. fuller understanding of looms of this type may be had V referring to the detailed description found in US. atents 2,641,285 and 2,888,965 which are hereby incor- Jrated by reference into the specification.

FIGURE 2 illustrates a pair of well known carrier elerents suitable for use in the above described loom appaltUS.

Transmitting carrier 32 is suitably secured to the end E tape 30 and the receiving carrier 33 is similarly secured i the end of tape 31. Slots 40 and 41 of transmitting irrier 32 receive the loop of filling thread which is adapted be projected into the shed by this carrier. Carrier 33 [so has a cut-away portion to the extent defined by the arallel sides 42, to thus provide a recess or cutout portion )r the entry of the cooperating portion of the receiving arrier 33. Combined trapping and tensioning member 43, 1 the form of a leaf spring, is secured at one end to the ody portion of the transmitting carrier 33 by any suitable leans such as screws 44 and cooperating plate 45. The :nsion pad 43 is spring-biased or tensioned in such a tanner as to exert a pressure at its free end against the irface 46 of filling engaging hook 47. The tension pad 43 ermits the loop of yarn carried by carrier 32 to enter 1e filling and engaging hook at the time of transfer and ue to the bias thereof in the direction of the inclined sur- 1C6 46 it provides proper tensioning of the filling during s extension through the remainder of the shed.

It can be seen from FIGURE 2 that should the carrier eads become misaligned for any of a multitude of rea- 3118, a collision between the transmitting and receiving arriers will result. It has been found that a frequent :sult of such a collision is the deformation of the tension ad 43 beyond its elastic limit as illustrated by the dotted ne position of the tension pad in FIGURE 2.

As shown in FIGURE 1, the tapes 30 and 31 are uided in their travel in and out of the shed by tape uides 48 and 49. In FIGURE 3 there is shown an eX- loded view of a receiving carrier tape guide structure onstructed in accordance with the teachings of the presnt invention. A U-shaped channel member 50 is fixedly ecured to the frame of the loom in any suitable manner 1 the position shown in FIGURE 1. The longitudinal hannel 51 is adapted to slidably receive the tape 31 and 1e longitudinal flanges 52 and 53 are eifective to prevent ateral movement of the tape. Vertical retaining and guide rembers 54 and 55 are fixedly secured by screws 56 and 7 to the vertical flanges 52 and 53 and prevent any vertial movement of the tape as it is reciprocated by the lriving means. Vertical retaining member 55 is preferably abricated from metal stock, however, it is, of course, to

be understood that any suitable rigid material will sufi'ice.

On existing looms both vertical retaining members are identical, however, in accordance with the present invention, a combined vertical retaining member 54 comprised of insulating member 60 and electrode member 61 is employed. As shown in FIGURE 3, retaining member 54 comprises an insulating member 60 and a conductive electrode member 61 which are suitably bonded together as shown by any suitable means such as gluing or the like. The insulating member 60 may be of any suitable material such as fiber 'board and serves to insulate the electrode member 61 from the channel member and also serves as the vertical retaining means for the tape 31. The combined insulator and electrode retaining means is secured to the channel member 50 by screws 56 which are insulated from the electrode member 61 by fiber washers 62.

As can be seen from FIGURE 3, the electrode member 61 is laterally offset from the insulator 60 and overlaps the edge thereof and also extends a distance past the end of the insulator. In accordance with the preferred embodiment of the present invention, the lateral offset is preferably approximately /s of an inch and provides an extension over the channel which is adapted to contact a sprung tension pad as described hereinafter. Further in accordance with the present invention, the extension of the electrode past the end of the insulator is chosen to be approximately 1 /2 inches and provides for an early (in terms of the reciprocating cycle of the carrier) sensing of a sprung tension pad. Adjustment holes 58 in insulator 60 in the cut-out portions 59 in the electrode member 61 are provided to enable the adjustment of the lateral position of the vertical retainer 54 with respect to the channel member 50.

In FIGURES 4 and 5 the receiving carrier guide is shown in its assembled form with the receiving carrier 33 and tape 31 operably disposed therein. In FIGURE 5 and end view of the receiving carrier and guide is shown. As can be seen from FIGURE 5 the vertical retainer and insulating member 60 serve to restrict the vertical movement of the tape 31 and carrier 33. The electrode member 61 extends over the channel 51 to a point short of engagement with the tension pad 43 of carrier 33 when in its normal position as shown. In accordance with a preferred embodiment of this invention the clearance between the electrode and the tension pad is chosen to be .02 inch when the loom is at front center. It can be seen from this figure that should the tension pad be sprung open, as shown in FIGURE 2, contact will be made with the electrode 61. By suitably connecting the electrode to the stop motion control circuitry, which is presently employed on looms of this type, the contacting of the tension pad with the electrode will be eifective to stop the loom and prevent the reinsertion of the receiving carrier into the shed.

FIGURE 6 illustrates schematically a portion of a suitable electrical stop motion control. The circuit shown is adapted to operate on direct current voltage, however, it is to be understood that an alternating current system may also be employed. A convenient method of obtaining the necessary DC voltage is shown and comprises the use of a full wave rectifying bridge 63 to convert the AC line voltage for the motor to DC potential. One output of the bridge is referenced to ground potential 64 and the other output of the bridge is connected by feed line 65 to terminal 66 to which are also connected two branch circuits. The first of these branches 67 leads to coil 68 of solenoid 70 and ground 71. The second branch 72 leads to one of the electrodes of a warp stop motion detector 73, the other electrode of which is grounded at 74. These electrodes are supplemented by a series of so-called drop wires, not shown, since the same and its action in this type of electrically actuated stop motion detector are well known and are disclosed in US. Patent No. 2,200,148. Upon release of a drop wire, due to the failure of a weaving thread, the detector circuit is grounded. A resistence R, having special characteristics, is placed in series in the feed line 65 so that current to either branch circuit must pass through it. This resistance preferably takes the form of an incandescent lamp such as a 12-16 volt truck type headlight bulb. The resistence of these lamps is relatively low when the filament is cold, however, when this lamp is caused to glow, the resistence increases very rapidly. Normally, a very small current, about /2 amp, is sufficient to energize magnetic coil 68 and hold the detent 75. This small current passes the lamp or resistance R without heating its filament appreciably.

When a thread fails and the circuit through the warp stop motion detector is completed, terminal 66 is in eifect, grounded which will cause increased current to flow through the lamp or resistance R. The combined effects of shorting terminal 66 to ground and the increased impedance of lamp or resistance R, due to the increased current, will cause the current in coil 68 to decrease to a value which is insufiicient to hold detent 75. Release of detent 75 is effective to knock off the loom in a well known manner such as that disclosed in US. Patent No. 2,884,106.

In accordance with the present invention the tension pad stop motion detector is connected into the above described circuitry via lead 76. The lead 76 is connected through a lamp 77 to terminal 38 of electrode 61 (FIG- URE 3). The schematically illustrated switch contact 78, which is shown connected to ground, represents the tension pad 43 which is mounted on the receiving carrier 33. The tape 31, securing carrier 33 and the tension pad 43 are preferably made of metal so that they provide an effective connection to the electrical ground system of the loom. Thus, it can be seen from FIGURE 5 that the contact of the tension pad 43 with the electrode 61 will short terminal 66 to ground to thereby cause solenoid 70 to release the detent 75 and knock off the 100m in the manner described above.

In order to insure the stopping of the loom, upon detection of a sprung tension pad before the receiving carrier again enters the shed, the electrode 61 is extended beyond the end of the receiving carrier guide to detect the existence of a sprung tension pad as soon as the receiving carrier is withdrawn from the shed. In order to further insure the rapid stopping of the loom, certain adjustments must be made in the motor 25.

FIGURE 7 shows a conventional motor and clutchbrake unit 25 which is employed on looms of the shuttleless type as shown in Patent No. 2,888,956. This unit is under the control of an arm 90 which is pivoted at 91 and adapted to control the position of a plate within the unit housing which may be alternately placed in driving engagement with a cooperating clutch plate or with a fixed brake member. This arm 90 is always biased by a spring 92 to the braking position. At the opposite end of the motor housing there is mounted suitable linkage means 94 for interconnecting the arm 93 to the end of arm 90. The arm 93 is connected at its other end to the shipper lever (not shown) of the loom whereby the displacement of the shipper lever is effective through arm 93 and linkage means 94 to displace arm 90 in a direction against the force of spring 92 to thereby disengage the brake and engage the clutch, to thereby drive the loom. The shipper lever and consequently the arm 90 are held in the clutchengaged position by conventional linkage means which are not shown herein but which are described in detail in Patent No. 2,884,106. This patent also discloses the manner in which the release of detent 75 (FIGURE 5) etfects the release of the shipper lever to enable spring 92 to force arm 90' back to the brake position to thereby stop the loom. The various elements required for this operation are not shown herein as they form no part of the present invention and are not necessary for the clear understanding thereof as these elements are well known to those skilled in the art.

In the normal operation of looms of the shuttleless type, the clutch-brake mechanism is set so that it takes 250 of travel time to stop the loom after the solenoid coil has been deenergized. In order to decrease this travel time and prevent the reentry of the receiving carrier into the shed, and in accordance with the present invention, the clutch gap is adjusted from the normal A of an inch to of an inch and a 2 inch helper spring 98 is added on the stop nut stud to decrease the travel time required to stop the 100m to approximately In operation, should a collision between the carriers occur, resulting in a sprung tension pad, as the receiving carrier is withdrawn from the shed, the sprung tension pad will contact electrode 61 to thereby short terminal 66 to ground which will, in turn, deenergize solenoid 70. Deenergization of the solenoid will in turn, cause the release of the shipper lever linkage mechanism in a well known manner to thereby disengage the clutch of the motor and engage the brake to thereby stop the loom within the travel time of 135 providing the adjustments suggested by the present invention have been made to the motor drive mechanism. The use of the elongated electrode 61 provides for a continuous contact between the tension pad and the electrode which results in a continuous supply of current to the indicator lamp 96 to notify the operator of the loom that a sprung tension pad has caused the stopping of the loom. The operator may then either repair the tension pad or replace the receiving carrier and then start the loom again by means of the shipper lever.

Thus, it can be seen that the present invention provides a simple and economical tension pad stop motion which may be incorporated in existing looms without any major alteration or modification.

From the foregoing description it will be apparent to those of ordinary skill in the art that the present invention is amenable to various modifications in the physical components, the combinations thereof and the electrical circuitry. It is to be understood therefore that the scope of the present invention is not intended to be limited by the foregoing description of a preferred embodiment of this invention, but on the contrary, is to be determined only by reference to the following claims.

What is claimed is:

1. In a loom of the shuttleless type having a transmitting carrier and receiving carrier wherein said receiving carrier has mounted thereon a tension pad, the free end of which is normally in contact with said receiving carrier, the improvement comprising:

sensing means disposed in proximity to the path of travel of said receiving carrier for detecting the existence of a sprung tension pad, loom knock oif means, and

means connecting said sensing means to said knock oif means for causing said knock otf means to stop the loom whenever a sprung tension pad is sensed and wherein said knock oif means has a terminal associated therewith, said knock off means being operable in response to the grounding of said terminal and further wherein said sensing means comprises an electrode disposed in juxtaposition to the path of travel of said receiving carrier for contacting said tension pad only when the free end of said tension pad is sprung out of engagement with said receiving carrier, and wherein said electrode is electrically connected to said terminal for grounding said terminal whenever said electrode is in contact with a sprung tension pad to thereby activate said knock off means.

2. In a loom of the shuttleless type having a transmitting carrier and receiving carrier wherein said receiving carrier has mounted thereon a tension pad, the free end of which is nomally in contact with said receiving carrier, improvement comprising:

sensing means disposed in proximity to the path of travel of said receiving carrier for detecting the existence of a sprung tension pad,

said sensing means comprising an electrode disposed in juxtaposition to the path of travel of said receiving carrier for contacting said tension pad only when the free end of said tension pad is sprung out of engagement with said receiving carrier, said electrode being electrically connected to said terminal for grounding said terminal whenever said electrode is in contact with the sprung tension pad to thereby activate a knock-off means, loom knock-01f means operable in response to the grounding of said terminal, and 4 means for connecting said sensing means to said knockoff means for causing said knock-off means to stop the loom whenever a sprung tension pad is sensed and including a receiver carrier tape guide, said electrode being fixedly secured thereto.

3. The apparatus of claim 1 wherein said electrode omprises an elongated rectangular member, the longiudinal axis thereof being parallel to the direction of travel f said receiving carrier for providing a continuous elecrical contact between said electrode and a sprung tension ad.

4. The apparatus of claim 2 wherein said receiving carier tape guide comprises a channel member having first nd second longitudinal flanges defining a longitudinal hannel therebetween and wherein said electrode is fixedly ecured to and insulated from said first longitudinal lange.

5. The apparatus of claim 4 further comprising an elonated rectangular insulating member and wherein said lectrode is an elongated rectangular member of similar .imensions, said electrode being laterally offset from and onded to said insulator and means for fixedly securing said insulator and electrode to said first flange, said insulator and electrode extending laterally into said longitudinal channel.

6. The apparatus of claim 1 further comprising indi cator means connected in series between said terminal and said electrode for indicating the existence of a sprung tension pad.

7. The apparatus of claim 1 wherein said knock-off means comprises a normally energized solenoid, the deenergization of which will cause the stoppage of the loom and wherein the grounding of said terminal is effective to deenergize said solenoid.

8. The apparatus of claim 7 wherein said knock olf means further comprises a source of electrical energy having said first and second outputs, means connecting said first output to ground, means connecting said second output to said terminal, means connecting said solenoid in series between said terminal and ground and indicator means connected between said terminal and said electrode whereby contact between said tension pad and electrode will energize said indicator means and deenergize said solenoid.

References Cited UNITED STATES PATENTS 2,884,016 4/1959 Sanderson et al 139-336 3,095,911 7/1963 Dewas 139370 FOREIGN PATENTS 987,789 3/ 1965 Great Britain.

HENRY S. JAUDON, Primary Examiner U.S. Cl. X.R. 139370

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