US3187700A - Sewing machine having automatic interrupter - Google Patents

Description

J1me 1965 R. DAVY SEWING MACHINE HAVING AUTOMATIC INTERRUPTER 4 Sheets-Sheet 1 Filed Nov. 16, 1964 INVENTOR.

June 8, 1965 R. E. DAVY 3,187,700

SEWING MACHINE HAVING AUTOMATIC INTERRUPTER Filed Nov. 16, 1964 4 Sheets-Sheet 2 a a o n n 1 r a a a a co INVENTOR.

Arme/VE/ June 8, 1965 R. E. DAVY 3,187,700

SEWING MACHINE HAVING AUTOMATIC INTERRUPTER Filed Nov. 16, 1964 4 Sheets-Sheet 4 8056 275: DAI/V INVENTOR.

FIGURE 1 United States Patent Office ddd'ifidfi Patented June 8, 1%65 This application is a con-tinuation-in-part of an application of Robert E. Davy, Serial No. 239,979 filed November 26, 1962, and now abandoned.

This invention relates to improvements in sewing ma 7 chines. It relates more particularly to power driven sewing machines. The invention resides primarily in an improvement or attachment whereby the stitching or sewing operation can be automatically initiated and terminated, or interrupted without stopping operation of the sewing machine itself. This is of very great advantage since frequent starting and stopping of the machine would cause excessive wear and deterioration. The improvement or attachment is a novel, simplified and very effective one.

The improvement of this invention has adaptability in many and varied applications of sewing machines, wherever it is desired to start and stop the stitching operation without starting and stopping the sewing machine.

The'improvement of this invention has been found to be highly adaptable in a machine used for stitching together long strips of paper to be used as wrappings for foods such as tamales as described in the application of Robert E. Davy, Serial No. 311,388, filed September 25, 1963, for Improved Food Receptacle. In this adaptation of the invention a line of stitching is automatically interrupted while the machine continues operating.

In a preferred form of the invention, the needle bar is operated by a pitman or connecting rod which drives a member which is slidable on theneedle bar, but which normally engages a collar on the needle bar for operating it. The collar is normally biased into engagement with the said member by a spring for normal operation. The collar has a lug which may be latched in a position out of engagement with the said driven member, with the spring compressed so that the needle bar is out of operative sewing positon whereby sewing is interrupted without interruption of the machine itself.

The invention also embodies improved indexing means for conventiently indexing the relative positional relationship as between the material being fed and the needle so as to accurately index or position the stitching relatively as respects the material.

In accordance with the foregoing, the primary object of the invention is to provide an improved and simplified means or attachment for interrupting the sewing or stitching operation of a sewing machine without terminating operation of the machine.

Another object is to provide improved means for accomplishing the foregoing object in an extremely effective way, particularly in that the initiation and interruption of stitching takes places at the stopped, reciprocatory positions of the needle bar.

Another object is to provide improved, effective and simplified means for indexing or controlling the relative positional relationship, as between materials being fed to a sewing machine and the position of interrupted lines of stitching of the material.

Further objects and additional advantages of the invention will become apparent from the following detailed description and annexed drawings wherein:

FIGURE 1 is a side elevational view of a preferred form of the invention, with upper portion of member 12 cut-away.

FIGURE 2 is'a View taken along the line 2-2 of The material after passing the sewing machine passes FIGURE 3 is a view taken along the line 3-3 of FIGURE 1;

FIGURE 4 is a sectional view taken along the line 44 of FIGURE 2;

FIGURE 5 is a view taken along the line 5-5 of FIGURE 2;

FIGURE 6 is a detail view of a part of the machine;

FIGURE 7 is an end view of the sewing machine showing the attachment of the invention;

FIGURE 8 is a View similar to that of FIGURE 7 showing the interruptervmechanism more in detail;

FIGURE 9 is a sectional view taken along the line 99 of FIGURE 8;

FIGURE 10 is an eieva-tional View of the sewing machine showing the cam actuators, partly in diagrammatic form.

FIGURE 11 is a detail view of the thread cutter;

FIGURE 12 is a diagrammatic view of the cam actuation of the presser foot;

FIGURE 13 is an exploded View of the needle bar, yoke, and thread arm assembly;

FIGURE 14 is a perspective view of the latch arm.

Referring now more in detail to the drawings, as may be seen in FIGURES 1 and 2, the machine comprises an upright frame structure it including uprights such as shown at 11, 12, 13 and 14. As may be seen in FIG- URE 2, there are additional upright structural members such as may be seen at 17, and supported at the upper part of the frame structure is .a platform or bed 19 on which is mounted the sewing machine unit itself designated at 21. Adjacent the platform or bed for the sewing machine 21 are the structural frame members as shown at 22, 23, 24 and 25 in FIGURE 3. The frame structure has horizontal structural members 29 and 3d at the top, as shown in FIGURE 3, which support guide and control means for the material after it has been stitched as will be described hereinafter.

Numeral 35 designates a transverse platform structure within the frame 10 which supports thereon certain components as will be described more in detail hereinafter.

Extending out from the feed side of the machine, as shown in FIGURE 1, is a frame structure 36 supported by members as shown at 37, and this structure supports the rolls of material to be stitched shown by way of example as rolls of paper 46 and 41. These rolls have central shafts 42 and 43 journaled in pedestal bearings such as shown at 44 and 45. The strips of paper feed upwardly through a roller assembly and then over the bottom platform of the sewing machine 21 underneath the presser foot and needle of the machine as will be described. The feed rollers are carried in a frame struc ture as shown at St? in FIGURE 3 on the feed side of the frame Hi. This frame structure has side members 51 and 52. The strips of paper pass under a cylindrical feed roller 53 on a shaft 54, which is journaled in bearings 56 and 57 mounted on the frame members 51 and 52. The strips of paper pass overan indexing sprocket roller as having two sets of sprocket teeth 61 and 62 69, the ends of which are journaled in bearings 71 and.

72 carried by the frame'members 51 and 52. .The strips of paper pass over a guide member 74 and under a member 75.

An interrupted line of stitching is shown at 77 in FIGURE 3 in a position beyond the sewing machine 21.

over platform 19 supported between the frame members 29 and 3t as'showninFlGURE 3. It passes under a guide plate 79 carried on a U-shaped clamping member a I or unit 89, attached to members 81and 82 extending from the frame structure. (See FIGURE 6.) These members support bearings 83 and 84 in which is journaled the shaft 85 of a rotary knife 86 which is driven in a manner to cut the strip into unit sections. The shaft 85 is driven by a sprocket wheel 92 in a manner which will be described more in detail presently.

The sewing machine 21, the sprocket roller 60 and the cutter rotor 86 are all driven from a motor which is designated by the numeral 94 in the figures. The motor 94 drives a pulley 96 as may be seen in FIGURE 2 through a clutch 97. The clutch is operated by a yoke 99 as may be seen in FIGURE 5 on a lever 100 pivoted on an extending arm 101 as may be seen in FIGURE 2 Lever 100 is connected to links 163 and 104 which in turn are connected to an operating handle 106 as may be seen in FIGURES l and 3.

The motor drives the sprocket roller and cutter rotor through a gear box and gear train which are-supported on the platform 35 previously referred to. These compomats are shown more in detail in FIGURE 4. The pulley 96 drives another pulley 108 on a shaft 109 through belt 110. This shaft connects to a timing pulley or unit 111 as may be seen in FIGURE 4, and then connects to a gear box 112 providing a gear ratio so that the various components are driven at appropriate speeds. The sewing machine 21 has an extending shaft with a timing pulley 132 on it. This timing pulley is driven by a timing belt 133 which passes over the timing pulley 111 previously referred to. The belt'is engaged by an idler pulley 135 on a shaft supported by bracketmembers as shown at 136 in FIGURE 5.

Extending from the gear box 112 as shown in FIGURE 4, is a shaft 114 having on it a bevel bear 115 meshing with another bevel gear 116, on a shaft 118 journaled in pedestal bearings 121 and 122 on the platform 35. On the shaft 118 is a sprocket wheel 127 which by means of link chain 129 drives a sprocket wheel 130 011 the shaft 69 of the sprocket roller 60.

As may be seen in FIGURE 4, on the shaft 118 are two cams and 141. These cams are also shown in FIGURE '10 and are part of the means for initiating and interrupting the sewing operations, as will be described presently. On the shaft 118 as shown in FIG- URE 4, there is a gear 143 meshing with a gear 144 on a shaft 146 journaled in pedestal ,bearings'147 and 148 on the platform 35. On the end-of shaft 146 is sprocket wheel 151 which drives sprocket wheel 92 through a link chain 153.

The link chain 129 which drives the sprocket roller 60 passes over an idler sprocket wheel and a second adjustable idler sprocket wheel 161. The idler sprocket 160 is mounted on arm "of bell crank lever 165 which is pivotally mounted on a shaft 163 as may be seenin FIGURE 1. Numeral 162 designates a second bell crank lever on which is mounted the. idler sprocket 161.. The bell crank lever 162 has an extending arm.

162' which is biased clockwise by spring 164. Bell crank lever 165 is adjustable byway of threaded stem 166 at the upper end of which is an operating crank 167. This stem engages a pivot block 163 at the end of hell crank 165. Numeral 169 designates'a'supporting bracket for stem 166 and numeral 170 designates a thrust collar under the bracket. Each of the two bell cranks has an inwardly extending boss at the hub, not shown, and when they are inv abutting relationship they cause the two idler sprockets 160 and 161 to fall. in alignment with the driving sprocket 127 at the bottom and the driven sprocket 130 at the top. The bell cranks are positioned on the shaft 163 by collars, not shown.

The direction of rotation of the adjustable drive as shown in FIGURE 1 is counter-clockwise. The idler sprocket 160 engages the pulling side of the chain. The idler'sprocket 161 on the spring biased bell crank lever 162 engages the slack side of the chain. The spring 164 pulls the upwardly extendingarm162' of bell crank' lever 162 in a clockwise direction causing the idler sprocket 161 to be forced against the chain. Since the driven sprocket 130 at the top is free to turn with the chain, all the slack is taken out of the chain causing it to engage the adjusting idler sprocket 160. This transmits a counter-clockwise thrust to the bell crank lever 165 which is taken by the thrust collar 170 under the mounting bracket 169.

FIGURE 6 is a detail view showing the clamping member 80 at the discharge end of the machine and the discharge platform. The cutter blade is shown at 86. As shown in this figure, there is a baffie member 172 having a bent part 173 which controls the paper after it has been cut. Clamping member 80 is U-shaped as may be seen in FIGURE 3, and pivoted on pivots 174. It is operated by arm and bracket 175 on which is mounted roller 178. This roller engages in a notch in disc or cam 179 on shaft 85. This causes member 80 to drop down into clamping position while the material is cut. This causes the material (i.e.) paper to buckle ahead of member 79 which guides it after release by member 80.

Associated with the cams 140 and 141 are. cam followers 176 and 177 as may be seen in FIGURES 1 and 10. These cam followers automatically control the initiation of sewing operation and interruption thereof, as will be described presently. The sewing machine itself, and the interrupter attachment will be described next.

The sewing machine itself is basically a conventional machine. It has a frame having a configuration as shown in FIGURES 2 and 7 to 10. FIGURE 7 is an end view of the sewing machine with the end plate removed, and showing the supporting plate 180 which supports the interrupter attachment. The machine has a reciprocatable presser foot bar .181at the lower end of which is a conventional pressure foot 182. At the upper end of the presser foot 'bar 181,iit is connected to a coupling member 183 having an extending end 184. Engaging this end member 184. is a coil spring 186, the upper end of which engages a spring retainer 187. This spring normally biases the presser foot bar 181 downwardly against the platform of the sewing machine. The presser foot may be manually lifted by an operating handle 191 pivoted on a pivot 192. It cooperates with the coupling 183 whereby the presser foot 182 may be manually lifted in a conventional manner. The presser foot 182 may also be mechanically (i.e.) automatically operated as described hereinafter. The machine shown herein is a chain stitch machine. The interrupter of the invention is however adapted to any type machine.

Numeral 200 designates a needle bar suitably journaled in the frame of the sewing machine. ,The needle bar carries the needle 201 .in a conventional position over the presser foot 182.

FIGURESS and 9 show the drive for the needle bar and'the thread arm 207. Shaft 203 has a rotor 204 on it thread arm are shown in FIGURES 7 and 8. The thread passes down from a spool on a spindle 208 on top of the machine as shown. It may pass through a conventional manually adjustable friction device and then down to the needle through the end of'thread arm 207 as-shown in FIGURE 7.

Fixed on the needle-bar 200 is a collar or yoke 210 having an extending lug 211.. See FIGURE/.13. Collar or yoke 210 engages an annular groove 212 out into needle with the yoke 266 by a coil spring 214, the upper end of which engages the frame of the sewing machine. In operation, rotation of shaft 203 reciprocates the yoke 206. By reason of its engagement with the collar 210 it thus reciprocates the needle bar 200 for normal sewing operation. Reciprocation of yoke 206 thus operates the thread arm 2&7 which otherwise operates in a conventional manner.

Interruption of stitching operation is accomplished by holding or positioning of the lug 211 and the collar 210 and needle bar.

The lug 211 moves in a slot 215 in the attachment plate 180 as may be seen in FIGURE 7. Pivotally mounted on the plate 180 is a bell crank lever 216 which is pivoted on a pivot 217. Lever 216 is shown more in detail in FIG- URE 14. This lever has a short arm 218 having a cutout forming a square shoulder as shown, which can be moved into a position as may be seen to engage under the lug 211 to hold it in an upward displaced position. The bell crank lever 216 has a longer arm 226 at the end of which is an eye 221 engaged on a rod or stem 222. The eye 221 is positioned between coil springs 224 and 225 on the stem 222 to provide a flexible or resilient connection. The eye member 221 has pivotal attachement to arm 220 to allow angular movement of lever 216. The bell crank lever 216 is operable, that is rotatable, by the stem 222. As may be seen, it may be moved into a latching position which latches the lug 211 in an upward position. Such position is shown in dotted lines in FIGURE 9. When the lug 211 is latched in that position, the collar 210 and needle bar 260 are held in an upwardly displaced position. In this position the needle 221 is held in a position above the platform 190 so that stitching is interrupted. In this position, on each revolution of shaft 203, the yoke 206 may intermittently'engage the collar 21!) to move it a relatively small amount, but sewing does not take place. When the bell crank lever 216 is in the position shown in FIGURE 7 the lug 211 is not held latched and normal sewing operation of the needle bar 200 may take place. As may be seen, the needle bar stops, and reverses its direction of motion twice during each revolution of the drive mechanism. Latching and unlatching of the needle bar takes place when the needle bar is stopped, this being a significant feature of the invention. Springs 224 and 225 are. balancing springs and are lighter than spring 214. 'Latching and unlatching are therefore extremely easy and take place only when lug'211 stops. These springs 224 and 225 bias lever arm 22%) either up or down depending on the position of rod or stem 222. As may be observed, if the lever arm 22% is biased upwardly by spring 225, and lug 211 is moving on the upward stroke, the latch 218 cannot engage until the lug reaches the upper limit of its stroke, as seen in FIGURE 7. As long as the lever arm 220 is biased upwardly the needle bar isheld. Throughout the rest of the stroke the full pressure of spring 214 is resting on the latch. seat and the balance springs are not strong enough to unlatch the mechanism. Unlatching takes place as described hereinafter.

The bell crank lever or latch arm 216 floats between the balance springs 224 and 225 on rod 222 which is threaded to receive adjustable lock nuts 270 and 271 and lock nuts 272 and 273 securing spring holder 275. Arm members 264, which is carried by presser foot bar 181 is slidably journaled on rod 222 abutting the lock nut 271. Spring 276 is attached between spring holder 275 and member 264.

In addition to the interrupter mechanism means are provided for initiating stitching or sewing operations. The automatic mechanism for operating the interrupter is shown in partly diagrammatic form in FIGURE 10. As may be seen in FIGURE 10, the stem 222 of the interrupter is connected to an arm 230 pivoted on a pivot 231 on the frame of the sewing machine. Arm 230 is connected by link 232 to a bell crank lever 234 pivoted on a pivot 236 on the lower part of the sewing machine frame.

6 Bell crank lever 234 has an arm 235 and this arm is connected by link 237 to the cam follower 176. It will be observed that an upward movement of stem 222 will rotate bell crank lever 216 in a counter-clockwise direction to latch the lug 211 and interrupt operations. An upward movement of stem 222 will be occasioned by a downward movement of link 232. This will be occasioned by the cam follower 176 dropping off the rise on cam 146 occasioning a downward movement of link 237 and arm 235.

As will be observed, when the lever arm 230 lifts the rod 222, spring 225 will be compressed causing latch arm 216 to be biased upwardly so that as the needle bar reaches the top of its stroke the latch will drop into the lug 211.

This stops the sewing operation. The cooperating mech- V anism operating the thread cutter operates simultaneously to cut the thread as described hereinafter. The thread is around the looper at the time it is cut, as described hereinafter.

The end of arm 23!) is bifurcated as shown in FIGURE 7 slidably receiving rod 222. When the right end of arm 230 is elevated the bifurcated and drops away from the stop nut 277. Prior' to initiation of a sewing cycle the bifurcated end of arm 239 is below stop nut 277.

It will be observed that when rod 222 is lifted by arm 23$), it does not lift the member 264 connected to the presser foot bar and presser foot 182. The presser foot has not yet been lifted so that the feed dog 255 continues to advance the material. The cut ends of the threads still disposed beneath the material are fed forward; an additional length of thread is pulled through the needle eye, after several cycles, the cam follower 177 lifts the presser foot 182 releasing the pressure on the cut thread, and as the material is pushed on forward by the index roller 66, the cut end of the thread to the needle is pulled out leaving it trailing on the top of the sewn material. As can be seen in this manner a tail is left extending in a position under the presser foot so that when sewing resumes, the thread will again be held by the presser foot so that it cannot be pulled out of the needle eye. This also leaves the thread extending after the seam'is sewn. By pulling this thread in a finished product, the seam is torn open giving access to the food within the package. Also, the

other cut end is left on the underside of the sewn material,

which locks the stitch so that it can not unravel as in conventional chain stitch sewing. 1

Bell crank lever 234 has another arm 246 connected by a link 241 to a lever 242 pivoted on a. pivot 243. One end of this lever is connected by a link 245 to a thread cutter, as shown at 247 in FIGURE 11, having a cutting blade 243 and a receiving notch for the thread as shown at 259. The thread cutter is pivotally mounted on the lower side of platform 199 as shown in FIGURE 11.

The sewing operation of the machine is conventional except for the thread cutting operation and its application with the looper. Numeral 255 in FIGURE 7 designates a feed dog assembly which is operated to feed the material 'to be worked on. This member is operated by conventional mechanism in the usual manner. Numeral 256 designates the thread looper which is itself conventional and cooperates in the sewing operation in holding the loops of thread below the presser foot 182. The feed dog assembly is conventional and comprises elements as shown at 255 which move through openings in platform 1% as shown at 2 66 in FIGURE 11. V

The thread cutter 247 is automatically operated at the end of a stitching operation. Its blade 248 goes directly between the thread strands held by a looper 256 and it may either cut or break the thread. If the'thread is not cut, the operation of the machine will break the thread leaving extending pieces of thread, one below and one above the stitched material. The upper piece is used to tear open the package when the material sewed is used for a package such as a'tarnale-wrapper. V j 2 Cam follower 177 drops off the dwell on cam 141 earlier in the cycle to initiate stitching operation. It actuates link 257, pivoted arm 258 and link 259 shown in FIGURE 12. Link 259 rotates lever 260 which rotates rod 261 about its axis. This rotates cam 262 which normally engages under lug 263 which is on coupling 183 of the presser foot bar as shown in FIGURE 7. This movement drops the presser foot bar; this actuates member 26 4, FIGURE 7, to move stem 222 downwardly to thereby move bel-l crank lever 246 to unlatch lug 211 and initiate stitching. This is accomplished by member 264 pulling downwardly on spring 276 to exert downward force on spring holder 275. This pulls down on rod 222 biasing spring 224. Sewing continues uninterrupted until cam follower 176 drops otfthe dwell of cam 140 which terminates sewing as previously explained. Cams 140 and 141 are relatively adjustable on their shaft 118.: By way of example for stitching food Wrappings the dwells on cams 140 and 141 may be 130 degrees apart with the follower 177 dropping ofi firstand follower 176 dropping off 130 degrees of rotation later.

From the foregoing, those skilled in the art will understand the mechanism of the machine, and its operation. As stated in the foregoing, the improved machine is adapted to many types ofsewing operations including sewing of garments and the like. In the exemplary embodiment shown, as described strips of paper are fed into the machine and sewn together with an intermittent line of stitching.

The foregoing disclosure is representative of a preferred exemplary form and adaptation of the invention and is to be interpreted in an illustrative rather than a limiting sense, the invention being accorded the full scope of the claims appended hereto.

What is claimed is: V

1. In a sewing machine having a reciprocating needle automatic means for intermittently and cyclically interrupting sewing operation of the needle, means for automatically and continuously feeding material to be stitched to the sewing machine, means driving said sewing machine and said feeding means in fixed time rclationto each other, means for indexing said feeding means relative to the sewing machine, said last means comprising a rotary member for feeding the material, an endless'drive member for said rotary member, an adjustable idler wheel cooperating with said endless member, and manual means for adjusting the position of said idler wheel whereby to adjust said drive member and said rotary memberand thereby to adjust the position of the material being fed relatively as respects the lines of stitching.

2. In a sewing machine having a frame, a needle bar assembly comprising a reciprooatable needle bar, a mem-: her on the needle bar and spring means-acting on said member normally urging the needle bar in one direction, reciprocatable means having engagement with said member for operating the needle bar, means for holding said member and needle bar in a position wherein said reciprocating means is ineifective for sewing operation by the needle bar, while operationof the reciprocating means continues, the said sewing machine having presser foot means, the improvement comprising means whereby said holding means is actuatable by the presser foot means for controlling the sewing operation.

3; In a sewing machine in combination, a frame, a needle bar assembly comprising a reciprocable needle bar, a memher on the needle bar and spring means acting on said member normally urging the needle bar in one direction, reciprocatable means having engagement with said member for operating the needle bar, means for holding said member and said needle bar in position to interrupt sewing operation by the needle bar while operation of said reciprocating means continues, the said sewing machine embodying material feed means, means to render said feed means ineffective during a period when sewing operation is interrupted, and additional material feeding means to continue to feed material through the machine while first feeding means are ineffective.

4. A machine .as defined in claim 3 including means for synchronizing the additional feed means with the sewing operation.

5. A machine as in claim 3 including material cut-otf means and means for synchronizing said cut-01f means with said additional feed means.

6. In a sewing machine having a reciprocating needle and feed means for advancing material past said needle, a drive comprising a needle bar, an abutment on said needle bar, a spring positioned to act on said abutment, a sliding member on said needle bar, means for driving said sliding member whereby to coa-ct with said abutment to reciprocate said needle bar, and an adjustable means cooperating with said abutment whereby to be operative to hold it in a position whereby to interrupt sewing operating of the needle and to release it to initiate sewing operation, said adjustable means comprising a latch member having a part engageable with said abutment to hold it in a position relative to said sliding member whereby to interrupt sewing operation, automatic cam means for intermittently operating said latch member, said cam means comprising a plurality of cams having cam followers with connections to said latch members whereby movements of one of said cam follower is operative to interrupt operation of said needle, the other cam follower being operative to thereafter render said material advancing means ineffective and then to render the same effective and to restartoperations of said needle.

7. A combantionas claim 6 wherein said sewing machine includes a thread cutter, and means whereby said :thread cutter is operated by one of said cam followers.

References Cited by the Examiner JORDAN FRANKLIN, Primary Examiner.

Claims (1)

1. IN A SEWING MACHINE HAVING A RECIPROCATING NEEDLE, AUTOMOBILE MEANS FOR INTERMITTENTLY AND CYCLICALLY INTERRUPTING SEWING OPERATION OF THE NEEDLE, MEANS FOR AUTOMATICALLY AND CONTINUOUSLY FEEDING MATERIAL TO BE STITCHED TO THE SEWING MACHINE, MEANS DRIVING SAID SEWING MACHINE AND SAID FEEDING MEANS IN FIXED TIME RELATION TO EACH OTHER, MEANS FOR INDEXING SAID FEEDING MEANS RELATIVE TO THE SEWING MACHINE, SAID LAST MEANS COMPRISING A ROTARY MEMBER FOR FEEDING THE MATERIAL, AN ENDLESS DRIVE MEMBER FOR THE ROTARY MEMBER, AN ADJUSTABLE IDLER WHEEL COOPERATING WITH SAID ENDLESS MEMBER, AND MANUAL MEANS FOR ADJUSTING THE POSITION OF SAID IDLER WHEEL WHEREBY TO ADJUST SAID DRIVE MEMBER AND SAID ROTARY MEMBER AND THEREBY TO ADJUST THE POSITION OF THE MATERIAL BEING FED RELATIVELY AS RESPECTS THE LINES OF STITCHING.

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