US3036534A

US3036534A - Apparatus for sewing on buttons

Info

Publication number: US3036534A
Application number: US767875A
Authority: US
Inventors: Martines Joseph
Original assignee: LOUIS RICH MACHINE CORP
Current assignee: LOUIS RICH MACHINE CORP
Priority date: 1958-10-17
Filing date: 1958-10-17
Publication date: 1962-05-29
Anticipated expiration: 1979-05-29

Description

May 29, 1962 .1. MARTINES APPARATUS FOR SEWING ON BUTTONS 4 Sheets-Sheet 1 Filed Oct. 17, 1958 INVENTOR. \M Q. MK

AT TO RNEYS May 29, 1962 J. MARTINES APPARATUS FOR SEWING ON BUTTONS 4 Sheets-Sheet 2 Filed Oct. 17, 1958 INVENTOR.

AT TORIi/EYS May 29, 1962 J. MARTINES APPARATUS FOR SEWING ON BUTTONS 4 Sheets-Sheet 5 Filed Oct. 17. 1958 ATTORNEYS M y 1962 J. MARTINES 3,036,534

APPARATUS FOR SEWING ON BUTTONS Filed Oct. 17. 1958 4 Sheets-Sheet 4 ATTORIEYS United States Patent f 3,036,534 APPARATUS FOR SEWING 0N BUTTONS Joseph Martines, New York, N.Y., assignor to Louis Rich Machine Corp., New York, N.Y., a corporation of New York Filed Oct. 17, 1958, Ser. No. 767,875

12 Claims. (Cl. 112-111) This invention relates to power-driven button sewing machines by which shank buttons of various sizes and designs, and flat buttons having either two or four holes, are sewed on fabrics by a single needle. The invention relates more particularly to button-sewing machines of the type in which the work remains stationary and the needle bar is oscillated parallel to the width of the sewing machine and the sewing elements are operated to form a chain stitch, the last two stitches being used as tying or additional securing stitches.

It is an object of the invention to provide an improved button sewing machine of the character indicated with simplified and rugged operating mechanisms for vibrating the needle bar. This permits faster operation, increased production and greater reliability in the performance of,

the machine. Another object of the invention is to provide an improved adjustable and movable combination needle guide and thread positioning finger for controlling the location of the thread loop engaged by the revolving looper of the sewing machine while the needle is either above or below the work or fabric, and properly timed to work in conjunction with the needle. This combination needle guide and thread positioning finger serves as positive assurance that a new thread loop will form about the previous thread loop properly.

In the preferred construction, the looper shaft for rotating the chain stitch looper is driven by a mechanism which promotes an intermittent circular movement which in turn gives the looper a varied speed so that the looper will be in a position to receive the thread loop when the needle bar is on either side of its side-to-side vibration which is parallel to the width of the machine and at right angles to the looper shaft. Part of this looper shaft driving mechanism revolves in an eccentric bushing, so designed to eliminate the slack or looseness in the gear driving connection between the looper shaft driving mechanism gear and the main shaft driving gear, which may arise as a result of general wear over a long period of time.

Another object of the invention is to provide a button sewing machine, of the character indicated, constructed so as to provide convenient and immediate means for changing the setting from a two-hole flat button to a fourhole flat button,

It is another object of the invention to provide improved means for sewing shank buttons. The invention provides a clamp for holding the shank buttons in proper relation to the vibrating needle bar, and the clamp is movable to allow for placement and removal of shank buttons quickly and conveniently and to allow for the break of the thread after the stitch cycle has been completed. One feature of the clamp construction relates to a work support which is adjustable up and down to accommodate shank buttons of various diameters without disturbing the adjustment of the other parts of the mechanism.

Other objects, features and advantages of the invention will be pointed out or appear as the description proceeds.

In the drawing, forming a part hereof, in which like reference characters indicate corresponding parts in all the views:

FIGURE 1 is a side elevation of a sewing machine made in accordance with thi invention;

3,@36,534 Patented May 29, 1962 FIGURE 2 is an end view of the button sewing machine shown in FIGURE 1, with the cover removed to expose the needle bar;

FIGURE 3 is a top plan view of the button holding clamp for the machine shown in FIGURES 1 and 2;

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

FIGURES 5, 6 and 7 are detail views showing parts of the button sewing machine; the structure shown in FIGURE 5 being on a greatly enlarged scale;

FIGURE 8 is a greatly enlarged sectional view taken on the line 8-8 of FIGURE 9;

FIGURE 9 is a diagrammatic bottom view of parts of the operating mechanism for vibrating the needle bar and for shifting the work clamp for four-hole buttons;

FIGURE 10 is a fragmentary bottom plan view of the cam drive and the looper drive mechanism of the machine;

FIGURE 11 is an enlarged view taken on the line 11-41 of FIGURE 10;

FIGURE 12 is a fragmentary top plan View, on an enlarged scale, showing the clamp for holding shank buttons;

FIGURE 13 is an end view of the apparatus shown in FIGURE 12;

FIGURE 14 is a front view, on a reduced scale, showing the shank button-holding attachment of FIGURES 12 and 13;

FIGURE 15 is a diagrammatic perspective view showing the stitch-forming mechanism of the machine;

FIGURE 16 is an end view of the thread-positioning finger and looper shown in FIGURE 15, and with the cam operating mechanism for the thread-positioning finger shown in dotted lines;

FIGURES 17, 18, 19, 20 and 21 are diagrammatic views showing the sequence of the stitching operation of the looper and the thread-positioning finger; and

FIGURES 17a, 18a, 19a, 20a and 21a are diagrammatic views showing the relative positions of the cam and cam follower corresponding to the looper and threadpositioning finger positions shown in FIGURES 17, 18, 19, 20 and 21, respectively.

The button sewing machine illustrated includes a base 30 to which is attached a standard 31 of conventional construction. Within the standard 31 there is a rocker arm 33 supported by a fulcrum bearing 34 attached to the standard 31. The rocker arm is operated by a pitman 36 which is connected with an eccentric 38 on a main drive shaft 40 of the sewing machine. The power is supplied to the main drive shaft 40 through a driving pulley 42; this mechanism being well understood in the sewing machine art.

On top of the standard 31 there are thread guide and tensioning means designated generally by the reference character 44; and there is a needle bar 46 at one end of the standard 31 with a needle 47 secured in a needle socket in the lower end of the needle bar 46,

The needle bar 46 reciprocates up and down in upper and

lower bearings

48 and 49, respectively. The upper bearing 48 is connected to the standard 31 by a stud 48' (FIGURE 4) secured to the bearing 48 and extending into a portion of the standard 31 in which the stud 48 is free to oscillate about the longitudinal axis 50 of the stud. The bearing 48 oscillates as a unit with the stud 48' to permit angular movement on the needle bar 46 about the axis 50.

The lower bearing 49 is attached to the forward end of an oscillating frame 52; and the lower bearing 49 is connected with this frame 52 by a stud 49" integral with the lower bearing 49 and extending into a complementary bearing socket in the frame 52 to provide a connection which permits oscillation of the lower bearing 49 about an axis generally parallel to the axis 50 of the upper bearing 48. This allows for changes in the obliquity of the needle bar 46 as the frame 52 oscillates about a vertical axis in a manner which will be explained in connection with the other views of the drawing. For the present it is suificient to understand that the frame 52 oscillates so as to move the lower bearing 49 toward the right and left, as viewed in FIGURE 2 and this moves the needle 48 back and forth between the positions indicated by the dotted lines in the FIGURE 2. The vibration of the needle, between the dotted line positions indicated, is timed with the up-and-down movement of the needle bar so that alternate stitches pass through different holes in the button when the machine is in operation.

The needle bar 46 is connected with the rocker arm 33 by universal link mechanism as shown in FIGURE 4. In this construction a clamp 56 is secured to the needle bar 46; and there is a stud 57 extending from the clamp 56 and supporting a ball 59 in a socket bearing 60 at the lower end of a link 62. This link 62 is connected to a bifurcated end of the rocker arm 33 by a rod 64. With this construction the needle bar 46 is free to move up and down while vibrating or oscillating about an axis at right angles to a vertical plane containing the axis about which the rocker arm 33 oscillates. This universal connection between the needle bar 46 and the rocker arm 33 provides a drive for moving the needle bar up and down without interfering with the oscillation of the needle bar from side to side.

FIGURE 3 is a top plan view showing a button clamp 68 with jaws 71 and 72 for holding a button 74. The holes in the button are oriented, as shown in FIGURE 3, so that the needle, in oscillating from side to side, engages the different holes alternately. The button shown in the clamp 68 in FIGURE 2 is a two hole button. FIGURE 3 also shows another button 75 having four holes and the holes are oriented in the position they will occupy when the button 75 is placed in the button clamp 68. The needle engages the two forward holes of the button 75. The button clamp is then moved, in a manner which will be explained in connection with the other views, to bring the other two holes of the button 75 into position to be engaged alternately by the needle to sew the rear 2 holes of the button to the work,

The frame 52, for oscillating the needle bar 46, is attached to the under side of the standard 31 for oscillation about a bearing 78 (FIGURE 4), and the frame 72 is held on the bearing 78 by a collar 79. The bearing 78 is part of a stud which projects through the bottom wall of the standard 38 and a head 80 at the upper end of the bearing 78 clamps a spring washer 82 against the wall of the standard 31 so as to hold the collar 79 against the frame 52 with a resilient pressure to provide a running fit, for the frame 52 between the collar 79 and the wall of the standard 31, and at the same time eliminate any axial play.

As further insurance against play in the operation of the frame 52, there is a stud 86 secured to the standard 31 near the connection of the frame 52 with the lower needle bar bearing 49. This stud 86 passes through a slot in the frame 52 but the head at the bottom of the stud 86 extends beyond the edges of the slot, so that the stud 86 prevents any downward movement of the forward end of the frame 52; but the slot is long enough so that the stud 86 does not interfere with the oscillation of the frame 52 about the axis of the bearing 78.

This construction of the stud 86 extending through the slot is shown in FIGURE 9 where the slot is indicated by the reference character 88.

FIGURE 9 shows, in dotted lines, the positions of the front end of the frame 52 at opposite ends of its oscillatin g movement.

Beyond the bearing 78, the frame 52 is off-set and it extends over a crank arm 90, best shown in FIGURE 4. This crank arm 90 is attached to a shaft 92 by a split clamp 94 at one end of the crank arm 90. The crank arm moves angularly in response to oscillation of the shaft 92 and as a unit with the shaft 92.

A slide block 96 is movable along a groove 98 in the crank arm 90. A threaded stud 99 extends upwardly from the block 96 and through a slot 108 in the portion of the frame 52 which extends along the length of the crank arm 90. There is a nut 102 threaded over the upper end of the stud 99, and this nut 102 can be used to clamp the block 96 at any location along the length of the slot If the slide block 96 is clamped in a position which locates the stud 99 on the axis of the shaft 92, then it will be evident that movement of the shaft 92 and the crank arm 90 will produce no movement of the frame 52 but will merely rock the block 96 about the axis of the stud 99.

If the slide block 96 is clamped in the position shown in FIGURE 4, then angular movement of the crank arm 90 will move the slide block 96 and impart an oscillating movement to the frame 52. The slide block 96 is always free to slide in the groove 98 of crank arm 98 to compensate for changes in the angular positions of the frame 52 and crank arm 98 as they oscillate about different axes. The total angular movement imparted to the frame 52 by the oscillation of the crank 90 depends upon how far the stud 99 is adjusted, along the slot 100, toward or from the axis of oscillation of the shaft 92.

The angle of the movement of the shaft 92 is constant, and the stud 99 is adjusted lengthwise of the slot 100 to make the angle of oscillation of the frame 52 produce the desired movement of the needle bar required for the particular spacing of the holes in the button on which the machine is to operate. An adjustable stop consisting of a bolt and nut assembly 104 can be used at a predetermined setting for positioning the stud 99 when buttons having a known hole spacing are to be sewed. When using the stop provided by the bolt and nut assembly 104, the nut 102 is loosened and moved along the slot 100 until it strikes against the stop provided by the bolt and nut assembly 104. When the machine is to be used for sewing two different sizes of buttons having different hole spacings, two stops can be provided along the slot 100 and the stud 99 can be shifted alternately between the different stops when the size of button is changed.

The shaft 92 rotates in bearings 108 and 109 extending upwardly and downwardly respectively, from the top of the base 30. A lower crank arm 112 is secured to the lower end of the shaft 92 and this lower crank arm 112 carries a follower 114 which runs in a track 116 in a cam 118-. The track 116 of this cam 118 is best shown in FIGURE 7. The number of undulations in the cam depends upon the number of stitches which the machine is designed to make with each cycle of operation. Each complete undulation of the cam 118 causes the follower 114 and the crank 112 to cause one oscillation of the needle bar 46 back and forth across the top of a button. The track or groove 116 of the cam 118 is designed to maintain the follower 114 and the connected parts stationary while the needle is operating to pass a thread through the button.

The cam 118 has slots 120 through which screws 122 extend for attaching the cam 118 to a hub of a worm wheel 125. This worm wheel meshes with a worm 127 on the main drive shaft 40 of the machine. The purpose of the slot 120 is to permit angular adjustment of the cam 118 for timing the operation of the follower 114 with the needle bar-operating mechanism of the machine.

There is another worm 131 on the main drive shaft 40; and this worm 131 rotates the worm wheel 132 to which another cam 134 is connected by screw 122 extending through the slots 120 in a manner similar to the connection of the cam 118 to the hub of the worm wheel 125. This cam 134 has a groove or cam track 136 which operates a cam follower 138 connected to a crank arm 140.

The crank arm 140 is attached to the lower end of a shaft 142 which rotates in a bearing 144 extending downwardly from the top wall of the base 38.

Another crank arm 146 is secured to the upper end of the shaft 144]; best shown in FIGURE 8. There is a groove 150 in the crank arm 146 providing a track along which a slide block 152 is movable. This slide block has a threaded stud 154 extending upwardly through a slot 156 in a crank 158 attached to the upper end of a shaft 160. There is a nut 162 attached to the threaded stud 154 for adjusting the position of the block along the slot 156 so that the crank 146 will impart any desired degree of angular movement to the other crank 158, or transmit no movement to the crank 158 if the stud 154 is adjusted into a position in line with the axis of oscillation of the shaft 140. This construction, and the purpose of it, is similar to the connection between the crank arm 95 and the frame 52 previously described. An adjustable step 184 is. pro vided on the crank 158.

The shaft 160 rotates in a bearing 164 in the top wall of the base 30; and there is another crank 166 secured to the shaft 160 just below the top wall of the base 36. The crank 158, shaft 160 and crank 166 move angularly as a unit about the axis of the shaft 160, the actual angle of the movement depending upon the setting of the stud 154 lengthwise of the groove 1541 in the operating crank 146.

The crank 166 extends under a shoe 17d; and there is a stud or shaft 172 extending downwardly from the shoe 170, through a slot in the top wall of the base 3% and then through a slot 175 in the crank 166 (FIGURE 5). This stud or shaft 172 serves as a cross head for reciprocating the shoe 170. A roller 177 fits over the shaft 172 and provides a low friction connection through which angular movement of the crank 166 imparts movement to the shaft 172.

The shoe 17d} slides on a bearing surface on the top wall of the base 341 and there are slide blocks 13d attached to the base 36 and located in the slot in the bottom face of the shoe 170 for confining the movement of the shoe to a straight line movement toward and from the needle 47. Thus angular movement of the crank 166 produces a straight line reciprocating movement of the shoe 1743; the stroke of the reciprocating movement depending upon the adjustment of the stud 154 (FIGURE 8) along the slot 156 to control the effective eccentricity or throw of the crank 158. A lug 184- extends upwardly from the shoe 170. There is a frame 186 provided with a bifurcated end extending along opposite sides of the lug 184, and which is connected with the lug by a pivot pin 188.

The button clamp 68 is connected to the forward end of the frame 186. An upwardly extending portion 191 of the frame 186 has a fiat surface 192 for engaging a pressure stud 193. This pin 193 extends into a recess in the bearing element 78, and spring pressure behind the stud 193 holds the stud in contact with the top surface 192. of the frame 186 so as to hold the button clamp 68 normally in a downward position with the button located adjacent to the work. There is a spring 194 attached to the shoe 170 and extend ing forwardly from the shoe 17 t} for holding a work piece against the top of the frame base when sewing a button to a work piece.

After sewing a button to a work piece, the frame 186 is raised, to break off the thread and to release the button clamp, by pulling the frame 186 upwardly with a chain 195 (FIGURE 1). This chain 195 is operated by a shaft 196 having a crank arm 197 at one end and a pull link 198 connected to a foot pedal on the floor. Such mechanism for raising the button clamp is conventional in sewing machines and no further description of it is necessary for complete understanding of this invention.

The spring-pressed stud 193 yields to permit upward movement of the frame 186 about the pin 183 as a fulcrum. The button clamp 68 at the forward end of the frame 186 is of conventional construction. The construction thus far described is used for sewing flat buttons.

6 A difierent frame and button clamp is used for sewing shank buttons to a work piece.

FIGURES 12 and 13 show the structure used for shank buttons. For greater convenience, the button clamp shown in FIGURES l2 and 13 is secured to the forward end of a frame 216 which is similar to the frame 186 and which can be conveniently attached to the machine, in place of the frame 186, by merely removing the pin 188 (FIGURE 1) and then replacing the pin 188 to hold a new frame 216 in place. The springpressed stud 193 holds the new frame down in the same manner as already described for the frame 186.

FIGURES 12 and 13 show a shank button holder 220 in which the shank button, indicated by the reference character 222, is held with the shank projecting beyond the holder 220. The fabric or Work piece 224 to which the button is to be sewn, is supported on a pad 226. The button 222 is clamped against the button holder 22% by a clamping finger 228 attached to the lower end of a bell crank 230. The clamping finger 228 is urged toward the button 22! by a tension spring 232.

The bell crank 23d oscillates at about a pivot 236 extending through a slot 238 and the bell crank can be adjusted to locate the pivot 236 at different places along the slot 238 for adjusting the button clamp for buttons of different size. An arm 2%, of the bell crank 230, has a threaded stud 2 11 which extends under the cam element 206 and contacts with the cam element to rock the bell crank 230 clockwise to release the clamping finger 228 from the button 222, when the frame 216 is raised at the end of a button-sewing operation.

The needle 47 is shown in FIGURE 13 in dotted lines indicating the opposite sides of its vibration or oscillating movement. In one position, the needle passes through the opening in the shank of the button 122, and in the other position the needle passes through the fabric or work piece 224.

In order to accommodate the machine to shank buttons of difierent diameter, the button holder 220 is made adjustable. It is attached to the front of the frame 216 by a bracket 2 .4 having a screw 246 which passes through a slot 248 in the bracket 244 to clamp the bracket to the end of the frame 216. Wherever the button holder 220 is to be raised or lowered to accommodate the buttons of different diameter, the screw 246 is loosened and the bracket 244 moved downwardly or upwardly as necessary, and the screw 246 is then tightened to hold the bracket 244 in its newly adjusted position.

As a further adjustment for buttons of different size the pad 226 is made vertically adjustable. A stud 250 extends downwardly from the pad 226 and is held in a sup porting clamp 254. The clamp 25 i is connected to a bracket 255. The clamp 254 has a screw 256 for closing the clamp against the stud 25%). Changes in the height of the pad 226 are effected by loosening the screw 256 and moving the stud 25% up or down in the clamp 254. Accommodations for buttons having shanks of different lengths are made by adjusting the bracket 255 toward or from the button clamp; there being slots 253 in the bracket 255 with screws 264 connecting the bracket to a supporting end of the frame 216.

FIGURE 11 shows the way in which the main drive shaft 4i) extends through a partition 262 in the base 30. The shaft 49 turns in a bearing in the base 36 and on the far side of the partition 262 there is a gear 266 secured to the drive shaft 49. The gear 266 meshes with similar gear 268 (FIGURE 11) on a shaft 276 which turns in a bearing vertical with the partition walls 262.

The partition 262 has a slot 272 extending from the front face of the partition to a bearing 273 in which the shaft 270 turns. This bearing 273 is an eccentric bushing and can be rotated in the paitition 262 to move the gear 268 closer to or further from the gear 266. There is a screw 275 extending through the partition 262 below the slot 272 and then threading into the upper part of the partition above the slot 272. By tightening or loosening the screw 275, the eccentric bearing 273 can be locked in any adjusted position. This provides a convenient means by which the

gears

266 and 268 can be brought closer together to take up any back lash during the original assembly of the machine or after some wear in the gears. The screw 275 is locked in adjusted position by a set screw 276.

There is a flange 280 secured to one end of the shaft 270, as best shown in FIGURE 4. This flange 280 drives another flange 282 through a link connection 234. Because of the fact that the link pivot of the flange 280 passes over the center of the axis of rotation of the flange 282, during one point in the rotation of the flange 280, the rotation of the flange 280 imparts an in termittent movement to the flange 282, for purposes which will be apparent in connection with description of the looper mechanism of the machine.

The flange 282 connected with one end of a looper shaft 288 which rotates in bearings in partitions 290 extending across one end of the base 30. There is a cam 292 on the looper shaft 288; and there is a cam follower 296 secured to another shaft 298.

FIGURE 15 shows a looper 302 secured to one end of the looper shaft 288 for movement as a unit with the looper shaft 288. A thread-positioning finger 304 is connected to the end of the shaft 298 for movement as a unit with this shaft 298; and the movement of the shaft 298, and its attached finger 304 is determined by the cam 292. FIGURE 15, shows the needle bar on its downward stroke, having entered through both button and fabric at the first of its series of lowest positions and the thread loop about to be received by the looper. The needle bar is at its right side stroke.

FIGURES 16 through 21a illustrate the operation of the looper and the thread-positioning finger and show the different positions of the cam 292 and follower 2% for the various positions of the looper and finger.

The thread-positioning finger 304 has an end portion 308 which serves as a needle guide, this end portion 308 being located adjacent to the path of the needle 48 so that the needle touches the finger to prevent the needle from moving outwardly in the direction of the end portion 308 of the finger 304. The thread-positioning finger 304 has a forked end 310 which is on the other side of the needle from the end portion 308 in position to cooperate with the thread and loop for purposes which will be explained.

FIGURE 16 shows the needle 48 with a thread 320 extending through a button 74 on a work piece 321. The thread passes downwardly through the work support and through the top wall of the base '30, and around the looper 302. FIGURE 16 shows the needle bar leav ing the button and fabric, the looper having picked up the first of a series of loops, and the needle bar traveling upwards, is about to complete its first right side stroke of the series of strokes.

As the sewing continues, the looper 302 rotates counter clock-wise, and so does the cam 392. This causes the forked end of the finger 304 to move towards the left in FIGURE 17 and deflect a loop 322 of the thread 320. The cam 292 and the cam follower 296 are in the relative positions shown in FIGURE 17a, during the operation illustrated in FIGURE 17 which shows the first loop formation and the needle bar travelling downward is making its first left side stroke and about to enter button and fabric.

As the sewing continues, the thread positioning finger 304 deflects the loop 322 somewhat further, as illustrated in FIGURE 18. This figure shows the needle bar having reached its left side low position and the looper moving in position to pick up thread loop for the complete formation of the first stitch.

The needle 47 moves upwardly again, and FIGURE 19 shows the looper having picked up the thread loop while needle bar is still at its first left side oscillation and travelling upwards to complete the formation of the first stitch. During this operation, the finger 304 remains in its position of deflection toward the left as the cam follower 296 moves along the high portion of the cam 292, as shown in FIGURE 19a.

FIGURE 20 shows the first stitch completely formed and the needle bar has begun to repeat the stitching cycle as it is now on its right side stroke again as in FIG. 15, and needle bar is beginning to travel upwards as the looper picks up the thread loop.

As the needle 48 rises, the finger 304 moves to the right while the cam follower 2% travels along the descending and low portions of the cam 29 2. During this same time, the looper 302 pulls the newly formed loop 332 downwardly and in doing so pulls the thread to take up the slack in the previously formed loop 322. Before the needle comes down again, however, the cam 292 turns the position shown in FIGURE 20a. A high point 336, on the cam 292, causes the finger 304 to move to its extreme left-hand position for an instant during which movement the finger draws the previous loop or stitch up tight against the bottom of the fabric or work piece 322. Immediately following this tightening of the thread, there is a depression in the face of the cam 292 which permits the finger 304 to again move toward the right, as seen in the drawings, and this provides the slack necessary to permit the looper to carry the loop 332 into position for the next downward stroke of the needle 47.

FIGURE 2.1 shows the next downward stroke of the needle '47 and shows the looper 302 in position to attach the loop in the thread while the finger 304 holds the previous loop 332 deflected so that the new loop 340 can be carried into the previously formed loop 332 to continue the sewing operation.

The improvement in the sewing operation performed by the looper and the thread-positioning finger, as herein described, is in the movement of the finger 304 by the high point 336 of the cam to draw the thread tight and more firmly secure the stitch under the button before the looper carries the thread down again preparatory to the next stitch. In the sewing machines of the prior art, the thread positioning finger could not move inwardly, as shown in FIGURE 20, to tighten the stitch because there was no provision for backing the finger away temporarily to permit the slackness for the looper to pull the loop down. If the finger 304 remained in the position shown in FIGURE 20, continued rotation of the looper 302 would increase the tension of the thread to the breaking point.

In the operations of the machines for sewing two hole buttons, the threaded stud 154 (FIGURE 8) and the slide block 152 are moved lengthwise along the groove of the cam 146 until the axis of the stud 154 is in line with the axis of the shaft 140. The nut 162 is tightened to hold the parts in the adjusted position, and in this position the angular movements of the crank 146 impart no movement to the crank 158 and the shoe (FIGURE 4) remains in one position during the entire operation of the machine.

When using the machine to sew four hole buttons, it is necessary to have the shoe 170 move to shift the second pair of holes in the button under the needle after the cycle of the machine has been half completed. Therefore, with four hole buttons, the threaded stud 154 (FIG- URE 8) is adjusted along the crank arm 146 so as to obtain the necessary eccentricity or throw required to shift the crank 158 as much as necessary to bring the second pair of holes in the button under the needle.

Different buttons have different spacing and the machine must be adjusted accordingly. This can be done by inserting a button in the clamp and turning the machine by hand until the cam operates the crank 146 to its maximum angular displacement.

The threaded stud 9 154 may then be moved along the groove 150 of the crank 146 until the crank had been shifted far enough to bring the button into the position necessary for the second part of the sewing cycle.

For all sewing operations, including the sewing of shank buttons, the threaded stud 99 (FIGURE 4) is adjusted to some position beyond the axis of the shaft 92 because some vibration or oscillation of the needle bar is always necessary with this machine where the work remains stationary. The position to which the stud 99 is adjusted, along the groove 98 of the crank arm 90 depends upon the distance between the holes of the button or the distance between the hole in a shank button and the point on the material to which the needle is to stitch the threads. The greater the stroke or oscillation of the needle bar by the crank arm 90, the wider will be the spacing of the stitching which holds the shank button to the Work piece.

The preferred construction of this invention has been illustrated and described, but various changes and modifications can be made and some features can be used in different combinations without departing from the invention as defined in the claims.

What is claimed is:

l. A sewing machine for attaching buttons to a work piece including in combination a stationary base for supporting a work piece, a button clamp assembly that holds a button and the work piece in fixed relation to each other and to the base, a standard carried by the base, a needle bar with means for holding a needle adjacent to the button clamp assembly, upper and lower bearings spaced from one another along the length of the needle bar and in which the needle bar has reciprocating movement toward and from the button clamp assembly, a pivot con necting the upper bearing to the standard for oscillation about a horizontal axis extending lengthwise of the machine, a frame including a rearwardly extending arm, a bearing on the standard and by which the frame is supported and with respect to which the frame is angularly movable about a vertical axis, another pivot connecting the lower needle bar bearing to said angularly movable frame, and operating mechanism for the needle bar including means for reciprocating the needle bar in said bearings and means for moving the frame back and forth angularly about its bearing in timed relation with the reciprocating movement of the needle bar, and in which the bearing for the frame is located on the standard above the base, the frame extending across the parts of the machine on which the work piece rests, and the means for moving the frame includes a crank arm pivotally connected with the rearwardly extending arm of the frame at a location beyond the frame bearing at a side of the bearing remote from the needle bar, and mechanism that oscillates the crank arm in timed relation with the reciprocation of the needle bar.

2. The sewing machine described in claim 1 and in which the crank arm is connected with the frame arm by a pin, and there is a slot in one of the arms and extending toward the axis of rotation of the crank and along which the stud is movable and adjustable into different positions to change the angular movement of the frame for buttons having different spacing between their holes.

3. The sewing machine described in claim 1 and in which there are means for shifting the button clamp assembly in a direction parallel to the axis of the oscillating movement of the upper bearing for the needle bar to accommodate the machine to sew four-hole buttons.

4. The sewing machine described in claim 1 and in which there are timing means for operating the needle bar a pre-determined number of times in a cycle, and the means for adjusting the button clamp assembly includes automatic mechanism operated in timed relation to the needle bar movement and at a mid point in the cycle of operation of the needle bar whereby approxii6 mately one-half of the operation of the needle bar is before, and the other one-half after, the shifting of the button clamp assembly to distribute the sewing between the different holes of a four-hole button.

5. A sewing machine for attaching buttons to a work piece including in combination a stationary base, a button clamp assembly that holds a button and the work piece in fixed relation to each other and to the base, a standard carried by the base, a needle bar with means for holding a needle adjacent to the button clamp assembly, upper and lower bearings spaced from one another along the length of the needle bar and in which the needle bar has reciprocating movement toward and from the button clamp assembly, a pivot connecting the upper bearing to the standard for oscillation about a horizontal axis extending lengthwise of the machine, a frame, a bearing by which the frame is supported and with respect to which the frame'is angularly movable about a vertical axis, another pivot connecting the lower needle bar bearing to said angularly movable frame, and operating mechanism for the needle bar including means for reciprocating the needle bar in said bearings and means for moving the frame back and forth angularly about its bearing in timed relation with the reciprocating movement of the needle bar, a'portion of the button clamp assembly extending upwardly toward a bottom surface of the standard, and resilient means, in alignment with the frame supporting bearing, and confined between the standard and said portion of the button clamp assembly for holding the button clamp assembly down against a work piece on the base.

6. The sewing machine described in claim 5 and in which the resilient means includes an abutment carried by the standard and spring means urging the abutment downwardly and into contact with said portion of the button clamp assembly.

7. The sewing machine described in claim 5 and in which the bearing supporting the frame is carried by the standard and extends downwardly therefrom, and the resilient means include a stud concentric with the frame supporting bearing and urged downwardly below the ad jacent portions of the frame and into contact with said portion of the button clamp assembly.

8. A sewing machine for attaching buttons to a work piece including in combination a stationary base, a button clamp assembly that holds a button and the work piece in fixed relation to each other and to the base, a standard carried by the base, a needle bar with means for holding a needle adjacent to the button clamp assembly, upper and lower bearings spaced from one another along the length of the needle bar and in which the needle bar has reciprocating movement toward and from the button clamp assembly, a pivot connecting the upper bearing to the standard for oscillation about a horizontal axis extending lengthwise of the machine, operating mechanism for the needle bar including means for reciprocating the needle bar in said bearings and means for moving the needle end of the needle bar back and forth angularly in timed relation with the reciprocating movement of the needle bar and in which there is a slide by which the button clamp assembly is carried, and there are guide means along which the slide is movable to shift the button clamp assembly along a line and in a direction parallel to the axis of the pivot of the upper needle bar bearing, a first crank, cam means and motion-transmitting connections between the cam means and the means for moving the needle bar for operating the first crank in timed relation to a cycle of operation of the needle bar, a second crank having a pivotal connection with the first crank, means for adjusting said pivotal connection along a guide in one of the connected cranks toward and from the center of oscillation of the crank having said guide to change the motion imparted to the second crank, and a crosshead that transmits motion of the second crank to the slide, the stroke of the crosshead being adjusted by 3,0 1 1 adjustment of said pivotal connection to accommodate the machine to buttons having different spacings between their holes.

9. The sewing machine described in claim 8, and in which the pivot connection is movable along the guide far enough to locate the pivotal connection over said center of oscillation at one position of adjustment to reduce to zero the movement of the crosshead when the machine is to be used for sewing buttons having less than four holes.

10. The sewing machine described in claim 8 and in which there is a hinge pin by which the button clamp assembly is connected to the slide at the rearward end of the button clamp assembly, and the pin extends transversely of the direction of movement of the slide so that the forward end of the button clamp assembly can be raised and lowered by moving the assembly about the hinge pin as a pivot, and said hinge pin is detachable from the button clamp assembly and the slide for convenient removal of the button clamp assembly from the machine when said assembly is to be replaced by other apparatus.

11. The sewing machine described in claim 8 and in which the button clamp assembly includes a holder for shank buttons, a support for holding a portion of the work piece near the shank and at an elevation above the base, the work piece support having means for holding it in any adjusted position.

12. The sewing machine described in claim 8 and in which the machine includes a stud connecting the button clamp assembly with the slide and about which the assembly swings to move it toward and from a work piece supported from the base, clamp jaws in said assembly for holding a button under the needle bar and over the work piece, lever means on the button clamp assembly and movable to set the opening of the jaws, so as to accommodate the button being sewed at the time, by means of a slight forward pressure.

References Cited in the file of this patent UNITED STATES PATENTS 1,226,963 Fifield May 22, 1917 1,514,609 Fifield Nov. 11, 1924 1,671,124 Plumby May 29, 1928 1,671,197 Lyons May 29, 1928 1,673,355 Fifield June 12, 1928 2,043,929 McCann June 9, 1936 2,131,012 McCann Sept. 20, 1938 2,298,246 McCann Oct. 6, 1942 2,360,471 Brussell Oct. 17, 1944 2,377,293 Reece May 29, 1945 2,495,069 McCann Ian. 17, 1950 2,883,951 Amman Apr. 28, 1959