US3526197A

US3526197A - Stitching machine

Info

Publication number: US3526197A
Application number: US666035A
Authority: US
Inventors: John E Hinckle
Original assignee: AMF Inc
Current assignee: AMF Inc; Automated Machinery Systems Inc
Priority date: 1967-09-07
Filing date: 1967-09-07
Publication date: 1970-09-01
Anticipated expiration: 1987-09-01
Also published as: SE350288B; DE1760495A1; FR1582097A; ES353551A1; GB1158695A

Description

United States Patent [72] Inventor John E. Hinckle Richmond, Virginia [21] Appl. No. 666,035 [22] Filed Sept. 7, 1967 [45] Patented Sept. 1, 1970 [73] Assignee American Machine & Foundry Company a corporation of New Jersey [54] STITCHING MACHINE 26 Claims, 30 Drawing Figs. [52] U.S.Cl 112/170, 112/226, 223/102 [51] Int. Cl D05b 1/00, D05b H24 [50] Field of Search 1 12/170. 171,176,178, 222, 226; 223/102; 128/339 (Curso'ry) [56] References Cited UNITED STATES PATENTS 139,745 6/1873 Tobey 112/170 1,065,058 6/1913 Lenler..... 112/170 2,074,942 3/1937 Scoma 112/226 Primary Examiner-Herbert F. Ross A ttorney George W. Price and Thomas W. Kennedy ABSTRACT: A stitching machine including a needle bar system, a thread handling system and a work handling system; in which the needle bar system comprises a first needle bar for passing a curved floating needle having an eye between its ends through which passes a short thread having a fixed end and a loose end through the work in a curved path of travel, e.g. to sew two pieces of work together with a blind stitch, and an opposed second needle bar for pulling the needle and returning the needle above the work to the first needle bar in a repetitive cycle; and in which the thread handling system comprises a looper for supporting the loose end ofthe thread and a thread puller traveling in a unidirectional path for pulling the loose end ofthe thread through the work, and disposing it on a thread receiver during each cycle of the machine.

Patented Sept. 1, 197a 3,526,197

Sheet 1 of 11 FIG. I

IN VENTOR.

JOHN E. HINCKLE 24W KM I ATTORNEY Patented Sept. 1, 1970 3,526,197

Sheet 2 of 11 JOHN E. HINCKLE W 60. NM

ATTORNEY Patented Sept. 1, 1970 3,526,197

Sheet '3 of 11 FIG; 3

I5 rs- INVENTOR. JOHN E. HINCKLE A OR Y Sheet 5 of 11 Patented Sept. '1, 1970 INVENTOR.

JOHN E. HINCKLE ATTORNEY Patented Sept. 1, 1970 Sheet 6 of 11 FIG. 9

FIG. IO

INVENTOR.

JOHN HINCKLE flwm/w W, f/Md T O Y .v

Patented Sept. 1, 1970 Sheet N K R E Ono N Wm w WA E v N M, H J

Y B 2 0 9M 8 w 2 0 65 a w 5 0 0 fi s 28 in mmw Z 9 Z 4 w w a 3 Patented Sept. 1, 1970 Sheet 9 of 11 ATTORNEY Patented Sept. 1, 1970 3,526,197

7 Sheet [Q of 11 W w. gwz g ATTORNEY Patented Sept. 1, 1970 Sheet H of 11 FIG. 30

INVENTOR. JOHN E. HINCKLE ATTORNEY STITCI-IING MACHINE The present invention relates to a short-thread sewing machine, and particularly to a floating-needle short-thread sewing machine.

The invention also relates to a blind stitching machine, which is capable of simulating hand stitching so that it is difficult to determine whether the stitching is done by hand or by machine.

The invention also relates to a novel method of blind stitching of components such as the parts which form the back of the collar ofa mans suit.

An important use of the machine and method embodying the invention is fell stitching, which heretofore in the art has been a laborious operation that required the close concentration of highly skilled seamstress or sewer. The present invention makes possible the production of what can be termed hand fell stitching.

Accordingly, it is one object of the invention to provide a novel short-thread sewing machine.

It is another object of the invention to provide a blind stitching machine, which is capable of simulating hand stitching and which can blind stitch the components which form the back ofthe collar ofa mans suit.

It is a further object of the invention to provide a blind stitching machine, which can produce fell stitching.

To the fulfillment of these and other objects, the invention providesa stitching machine including a needle bar system, a thread handling system and a work handling system; in which the needle bar system comprises a first needle bar for passing a curved floating needle having an eye between its ends through which passes a short thread of a preselected length having a fixed and a loose end through work to be stitched in a curved path of travel, and an opposed second rotary needle bar for pulling the needle and returning the needle above the work to the first needle bar in a repetitive cycle.

Other objects of the invention will become apparent upon reading the following description and accompanying drawings, wherein like parts are designated by like numerals throughout the several views, and wherein:

FIG. 1 is a front elevation view of a floating-needle shortthread sewing machine embodying features of the present invention;

FIG. 2 is a plan view taken along the line 2-2 ofFIG. 1;

FIG. 3 is a sectional view taken along the line 3-3 of FIG.

FIG. 4 is a perspective view similar to FIG. 3;

FIG. 5 is a sectional view taken along the line 5-5 of FIG.

FIG. 6 is a sectional view taken along the line 6-6 of FIG.

FIG. 7 is a sectional view taken along the line 7-7 of FIG.

FIG. 8 is a sectional view taken along the line 8-8 of FIG.

FIG. 9 is an enlarged sectional view taken through the front chuck;

FIG. 10 is an enlarged sectional view taken through the rear chuck; I

FIG. 11 is an enlarged view of the needle portion only of FIG. 3;

FIG. 12 is a plan view taken along the line 12-12 of FIG.

FIG. 13 is a sectional view taken along the line 13-13 of FIG. 3;

FIG. 14 is a sectional view taken along the line 14-14 of FIG. 3;

FIG. 15 is a sectional view taken along the line 15-15 of FIG. 3;

FIG. 16 is a sectional view taken along the line 16-16 of FIG. 2;

FIG. 17 is a sectional viewtakcn along the line 17-17 of FIG. 16;

FIG. 18 is an enlarged view ofa portion of FIG. 17;

FIG. 19 is a sectional view taken along the line 19-19 of FIG. 16;

FIGS. 20-26 inclusive are views illustrating the sequence of operation in forming a typical blind stitch. FIG. 27 is a sectional view taken along the line 27-27 of FIG. 26;

FIG. 28 is a sectional view taken along the line 28-28 of FIG. 27;

FIG. 29 is a sectional view taken along the line 29-29 of FIG. 1; and FIG. 30 is a sectional view taken along the line 30-30 of FIG. 29.

Referring to FIGS. 1, 2, one embodiment of the present invention is a machine 10. Machine 10 comprises a support structure 12, a drive means 14, a needle bar system 16, a thread handling system 18, and a work handling system 20. Machin 10 sews a workpiece 22.

Needle bar system 16 (FIGS. 2, 3) has a horizontal reference axis 24. Work handling system 20 (FIGS. 2, 26) has a horizontal reference axis 26, and a vertical reference axis 28.

Horizontal axes

24, 26 substantially intersect vertical axis 28 substantially at right angles thereto. Horizontal axis 24 substantially intersects a plane through

axes

26, 28 at a fixed reference angle 30. Drive means 14 (FIGS. 2, 3) has a horizontal reference axis 32, which is substantially parallel to bar axis 24.

Support structure 12 (FIGS. 1, 2) includes a floor panel 34, a left wall panel 36, a right wall panel 38, a rear wall panel 40, and a top panel frame 42. Support structure 12 also has a stitcher support 44, which is supported by a top panel frame 42 and which supports needle bar system 16 and thread handling system 18.

Stitcher support 44 (FIGS. 1, 2) has front and rear sidewalls 46, 48 and left and

right sidewalls

50, 52. Stitcher support 44 also has a cantilever beam 54 with front and

rear support walls

56, 58.

Drive means 14 (FIGS. 1, 2) includes a motor 60, a clutch 62, a lower transverse drive shaft 64, and an upper diagonal drive shaft 66, which is coaxial along reference axis 32.

Motor 60 and clutch 62 are mounted on panel 40. Clutch 62 has a clutch pedal 68. Motor 60 and clutch 62 have an interconnecting belt 70 whereby motor 60 drives clutch 62. Clutch 62 and shaft 64 have an interconnecting belt 72, whereby clutch 62 drives shaft 64.

Upper shaft 66 has a pair of meshing

bevel gears

74, 76. Gear 76 has a stub shaft 78. Stub shaft 78 and lower shaft 64 are interconnected by a belt 80, whereby lower shaft 64 drives upper shaft 66. Upper shaft 66 also has a ring gear 82, which drives a wheel shaft 84 through a bevel gear 86. Wheel shaft 84 connects to the thread handling system 18, upper shaft 66 connects to the needle bar system 16, and lower shaft 64 connects to the work handling system 20, as explained hereafter.

Needle bar system 16, (FIGS. 2, 3), which is the stitcher, is symmetrically disposed about axis 24. System 16 includes a front needle bar unit 88, a rear needle bar unit 90, and a curved needle 92.

Needle bar units 88, are supported by vertically-displaceable hanger 94.

Needle bar units

88, 90 and needle 92 are rotatable about axis 24. Needle 92 is alternately supported by

needle bar units

88, 90. Front bar unit 88 (FIG. 3) moves within a set travel angle 96; and rear bar unit 90 moves within a different travel angle 98.

Front bar unit 88 (FIGS. 3, 5, 7) comprises a front needle chuck 100 carried by one end of shaft 102. This shaft (FIG. 5) is rotatably supported by hanger 94. Actuating lever 104 is attached to the other end of shaft 102. Actuating lever 104 is oscillated by a pair of interconnecting

links

106, 108. Link 106 is pivotally connected to lever 104, and link 108 has a follower wheel 12, which runs in track 116 of cam 114. Link 108 is also supported at one end by bracket 110, which is fixedly pinned to wall 56. Through the connections described, cam 114 is responsible for the rotary and oscillatory movements of shaft 102 and chuck 100 carried thereby.

Front chuck 100 (FIGS. 3, 5,8,9) has an arm 118, which is fixedly connected to shaft 102, and a head 120, which is supported by arm 118. Head 120 has a pair of split plates 122, 124. Plate 124 is integrally connected to arm 118 and plate 122 is connected to plate 124 by screws 126 (FIG. 8). Plates 122, 124 respectively have opposite engaging

surfaces

128, 130. Head 120 has an inner end face 132 and an outer end face 134, which are common to plates 122, 124. As shown in FIG. 3, inner face 132 is used to define chuck travel angle 96 for ease of reference.

Front chuck 100 (FIGS. 8, 9) has an elongated curved needle seat or passage 136, which extends inwardly from inner face 132 toward outer face 134 for receiving needle 92. Front chuck 100 also has a detent mechanism 138, which is disposed adjacent passage 136 for locking needle 92 in passage 136 and a detent actuator 140 for opening detent mechanism 138.

Passage 136 has a needle-stop shoulder portion 144, which is disposed adjacent outer face 134. Passage 136 has an elongate sidewall 146 of substantially circular cross-section. Sidewall 146 has a groove 148 with a bottom cam surface 150.

Detent mechanism 138 (FIG. 9) includes a semispherical ball 152 with a spherical center 154, an elongate plunger pin 156 and a spring 158, which are received in groove 148. Spring 158 urges ball 152 toward inner face 132 in order that it may engage and lock needle 92, as explained hereafter. Pin 156, which is fixedly connected to ball 152, has a handle 160 to pull pin 156 against spring 158 and thereby pull ball 152 away from needle 92 in passage 136. Pin 156 is supported by bearing surface 142.

Detent actuator 140 (FIGS. 3, 9, 14) includes a stop bar 162, which is fixedly mounted on hanger 94. Stop bar 162 is angularly positioned adjacent the path of travel of chuck 100 so as to engage handle 160 and separate ball 152 from needle 92 in passage 136 (FIG. 9) by a gap 164 within a small angular portion 166 (FIG. 3) of chuck angle oftravel 96 in response to the movement by chuck 100 clockwise (FIG. 3). In this way, the unlocking operation is completed and chuck 188 can slide needle 92 out from passage 136.

In the locking operation after needle 92 is seated by chuck 188 in passage 136 against shoulder 144, ball 152 and needle 92 remain stationary, and chuck 100 moves counterclockwise and upwardly away from ball 152 and needle 92. As chuck 100 moves upwardly, cam surface 150 urges ball 152 against needle 92 whereby needle 92 is locked to chuck 100. Bearing surface 142 supports pin 156 at one end of pin 156, whereby the other end of pin 156 supporting ball 152 has a pivoting action relative to surface 142.

Rear bar unit 90 (FIGS. 5, 6) comprises a needle chuck 168 carried by one end of shaft 170. This shaft (FIG. is rotatably supported by hanger 94. Actuating lever 172 is attached to the other end of shaft 170. Actuating lever 172 is oscillated by a pair of interconnecting

links

174, 176. Link 174 is pivotally connected to lever 172, and link 176 has a follower wheel 180, which runs in track 184 of cam 182. Link 176 is also supported at one end by bracket 178, which is fixedly pinned to wall 56. Through the connections described, cam 182 is responsible for the rotary and oscillatory movements ofshaft 170 and chuck 168 carried thereby.

Rear chuck 168 (FIGS. 3, 5, 8, 9) has an arm 186, which is fixedly connected to shaft 170, and a head 188, which is supported by arm 186. Head 188 has a pair of

split plates

190, 192. Plate 192 is integrally connected to arm 186 and plate 190 is connected to plate 192 by screws 194 (FIG. 8).

Plates

190, 192 respectively have opposite engaging

surfaces

196, 198. Head 188 has an inner end face 200 and an outer end face 202, which are common to

plates

190, 192. As shown in FIG. 3, inner face 200 is used to'defme chuck travel angle 98 for ease of reference.

Rear chuck 168 (FIGS. 8, has an elongated curved needle seat or passage 204, which extends inwardly from inner face 200 toward outer face 202 for receiving needle 92. Rear chuck 168 also has a detent mechanism 206, which is disposed adjacent passage 204 for locking needle 92 in passage 204 and a detent actuator 208 for opening detent mechanism 206.

Passage 204 has a needle-stop shoulder portion 212, which is disposed adjacent outer face 202. Passage 204 has an elongate sidewall 214 of substantially circular cross-section. Sidewall 214 has a groove 216 with a bottom cam surface 218.

Detent mechanism 206 (FIG. 9) includes a semispherical ball 220 with a spherical center 222, an elongate plunger pin 224 and a spring 226, which are received in groove 216. Spring 226 urges ball 200 toward inner face 200 in order that it may engage and lock needle 92, as explained hereafter. Pin 224, which is fixedly connected to ball 220, has a handle 228 to pull pin 224 against spring 226 and thereby pull ball 220 away from needle 92 in passage 204. Pin 224 is supported by bearing surface 210.

Detent actuator 208 (FIGS. 3, 10, 14) includes a stop bar 230, which is fixedly mounted on hanger 94 and preferably formed integrally with bar 162. Stop bar 230 is angularly positioned adjacent the path of travel of chuck 168 so as to engage handle 228 and separate ball 220 from needle 92 in passage 204 (FIG. 10) by a gap 232 within a small angular portion 234 (FIG. 3) of chuck angle of travel 98 in response to the movement by chuck 168 counterclockwise (FIG. 3). In this way, the unlocking operation is completed and chuck can slide needle 92 out from passage 204.

In the locking operation after needle 92 is seated by chuck 100 in passage 204 against shoulder 212, ball 220 and needle 92 remain stationary, and chuck 168 moves clockwise and upwardly away from ball 220 and needle 92. As chuck 168 moves upwardly, cam surface 218 urges ball 220 against needle 92 whereby needle 92 is locked to chuck 168. Bearing surface 210 supports pin 224 at one end of pin 224, whereby the other end of pin 224 supporting ball 220 has a pivoting action relative to surface 210.

Needle 92 (FIG. 11) is an elongate curved member of suitable length, and is circular in cross-section. It also has a pointed front end 238, a blunt rear end 240, and an eye 242, which is disposed between ends 238, 240 and which can be threaded with a selected length of thread 244. Needle 92 is provided with suitable reduced

portions

256 and 260, which during the operation of the machine are engaged alternately by

detents

152 and 220 to lock needle 92 in one or the other of

chucks

100, 168. It will be apparent that needle 92 can have a different cross-sectional shape, if required.

Needle 92 is threaded with a selected length of thread 244 and the length may vary depending on the amount of blind stitching to be effected. Before the first stitch is made, both ends of the thread 244 are loose, as shown in FIG. 20. When the first stitch is made, and thereafter, as shown in FIG. 25, one end of thread 244 is a loose end 245 and the other end is a fixed end 247.

Workpiece 22, which may be an undercollar of mans coat, includes a lower cloth 270 and an overlapping upper cloth 272. Upper cloth 272 has an edge or seam 274.

After needle 92 and thread 244 are pulled up from workpiece 22, as shown in FIG. 4, loose end 245 has a near loop portion 246 on the near side of needle 92 and the fixed end 247 has a far loop portion 248 on the far side of needle 92. The manner in which thread 244 is manipulated is described hereafter. Needle 92 (FIGS. 3, 8, 14) moves through a forward travel path 250 in its forward travel, counterclockwise in FIG. 3; and through a return travel path 252 in its return travel, clockwise in FIG. 3. Axis 24 is displaced an offset distance 254 (FIG. 3) on the return travel of needle 92.

Paths

250, 252 are in a plane of rotation, which is disposed substantially at right angles to axis 24.

In the operation of machine 10, a complete blind stitch 264 is made as the result of the forward travel and return travel of needle 92. Stitch 264 includes a blind understitch portion 266 or one which cannot be seen and an overstitch portion 268. Stitch 204, as shown in FIG. 13, is called a fell stitch or a felling stitch.

Hanger 94 (FIGS. 3, 5, 8) includes a body portion 276 with a vertical slot 278, a pair of support pins 280, 282, and a guide plate 284.

Pins

280, 282 which are supported by wall 56, extend through slot 278 and connect to plate 284 so that body 276 is supported by wall 56 and plate 284. Hanger body 276 has a shoulder portion 286 with a follower wheel 288.

Hanger 94 also includes a closed cam 290, fixed to upper shaft 66. Cam 290 has a cam track 292 on which wheel 288 rides for raising and lowering body 276. In this way, chucks 100, 168 and needle 92 are lifted and axis 24 is moved through its offset distance 254, on the return travel of needle 92.

Thread handling system 18 (FIGS. 3, 4) includes a looper 296, a holder 298, a gripper 300, a thread puller 302, a receiver 304, and a pusher 306. System 18 may also have a spreader 294, as explained hereafter.

Looper 296 (FIGS. 3, 4, 5 and comprises an arm 314, on the free end of which is mounted a thread loop engaging guide finger 312 and a spacer 322. Arm 314 is pivotally supported on a stub shaft 330 mounted in a bracket plate 324 (FIG. 4) attached to or formed integrally with wall 56. Arm 314 is also provided with an integral eccentric arm 332 having a slot 326 in which is slidably pivotally connected one end ofa link 316, the other end of which is pivotally connected to the free end of lever 318 swingably mounted on pin 358 in a bracket 346 also attached to wall 56.

Lever 318 carries a cam follower 350 which runs in track 354 of cam 352 mounted on shaft 66. This mechanism effects the desired timed movement of looper guide finger 312 and roller 322 into engagement with a loop of thread and insures the travel of the thread engaged thereby from a pick-up to a delivery position.

In operation, looper arm 314 travels along path 320 just before front chuck 100 begins its return stroke. Finger 312 engages near loop 246 and due to its sloped surface cams it onto spacer 322. Looper 296 lengthens near loop 246 by pulling thread through workpiece 22, and causes near loop 246 to be delivered into hook 360 of holder 298.

Holder 298 (FIG. 3) comprises an elongated rod-like member having a generally circular thread receiving hook 360 on its lower end, and an enlarged upper end 358 with a rod portion 356, which is supported from bracket 346.

In operation, lower hook 360 supports near loop 246, after loop 246 is delivered thereinto by looper 296. Hook 360 positions near loop 246 adjacent gripper 300 and holds it in position to be engaged by thread puller 302 which pulls the entire loose end 245 of the thread through workpiece 22.

Gripper 300 (FIGS. 3, 15) comprises a movable finger 362 and a fixed finger 364. Finger 364 has a body portion 366 which is supported by wall 56, and an anvil-type bearing face 368.

Finger 362 (FIG. 15) includes an upper portion 370 and a lower portion 372. Lower portion 372 has a tapered cam surface 374.

Portions

370, 372 are pivotally mounted in a hinge connection on pin 376 mounted in portion 370.

Cam 380 (FIGS. 3 and 15) is fixedly connected to shaft 66 and is provided with a track 382 on which runs cam follower 390 mounted on one end of lever 384 rockably carried on stub shaft 391 in portion 370. A cam follower 392 on the other end of lever 384 engages tapered cam surface 374 on lower portion 372. A spring 388 having one end attached to connector 394 on wall 56 and its other end held by connector 396 on lower portion 372 maintains proper tracking engagement between the cam follower and other respective cams. Lower portion 372 (FIG. 15) has a bearing face 398, which holds near loop 246 against bearing face 368, and a lap shoulder 400, which forms a groove 402 for catching and holding loop 246. The coaction of the mechanism just described results in the desired relative movement between

finger

362 and 364 and the holding and release of thread delivered thereto during the operation of thread puller 302.

Fingers

372 and 368 grip or hold the fixed end 247 of the thread 244, which is also supported in hook 360, in position for puller finger 404 to engage it and to pull the loose end 245 of the thread 244 thru the work and dispose it in the receiver 304. Thus, there will be no puckering of the thread in the workpiece 22 due to puller finger 404 overtensioning the fixed end 247 of the thread and the last stitch formed in workpiece 22.

Thread puller 302 (FIGS. 2, 16, 17, 18, 19) includes a thread engaging finger 404 with a guide groove 407 to receive near loop 246. Puller 302 has an actuating mechanism 406 timed to coact with looper 314 and gripper 300.

Actuating mechanism 406 (FIGS. l6-19) includes an upper track 408 and a lower track 410, a drive wheel 412, an idler wheel 414, and a timing belt 416. Idler wheel 414 has a supporting shaft 418, which is supported by wall 56. Drive wheel 412 is supported by shaft 84, which is supported by wall 58. Timing belt 416 is coupled in a conventional manner to

wheels

412, 414. Belt 416 is connected to thread puller 404. Belt 416 and drive wheel 412 are driven by upper shaft 66, whereby there is a coordinated action of puller 404 with bars 88, and first looper 296.

Upper track 408 includes a pair of

upper rails

420, 422, and an upper spacer 424, which are connected together by bolts 426. Lower track 410 includes a pair of

lower rails

428, 430, and a lower spacer 432, which are connected together by bolts 434.

Bolts

426, 434 are supported by receiver 304, as explained hereafter.

Receiver 304 (FIGS. 2, 16, 17, 18, 19) includes an angle portion 436, a base portion 438, a curb portion 440, and a thread retaining cover 442.

Angle portion 436, base 438 and curb 440 form an elongated member having rounded ends (FIG. 16). Angle 436, base 438 and curb 440 are assembled together by bolts 426, and are supported by support bolts 444 from front wall 56 and rear wall 58. Angle portion 436 has a horizontal leg 446 and a vertical leg 448. Horizontal leg 446 (FIG. 18) has a longitudinal outer groove 450.

Base 438 (FIG. 18) has an outer face 452 with a sloping step portion 454. Leg 446 overlaps outer face 452 and forms a chamber 456 adjacent step 454 and forms a continuous passage 458 between leg 446 and face 452.

Cover 442, which is an elongate flexible strip, has a spring connector 460, which connects to wall 56, and has a spring connector 462, which connects to curb 440. Cover 442 over laps groove 450 and chamber 456. Cover 442 is supported by holder rod 356 adjacent connector 460. Cover 442 has a support rod 464, which is disposed adjacent connector 462 supported by curb 440.

In making stitch 264, finger 312 pulls loop 246 in a unidirectional path away from

bars

88, 90, and disposes a portion of near loop 246 on book 360. Then, finger 404 (FIG. 18) pulls the loose end 245 of the thread through hook 360 for placement in receiver 304. Within receiver 304, the loose end 245 of the thread (FIG. 18) has an upper portion 466, disposed in groove 450, and a lower portion 468, disposed in chamber 456. Upper portion 466 extends from finger 404 through groove 450 to hook 360, and from hook 360 to workpiece 22. Lower portion 468 extends from finger 404 through chamber 456 to gripper 300, and from gripper 300 to needle eye 242. As described previously, far loop 248 extends from needle eye 242 to workpiece 22.

Loose end 245 of thread 244 has a trailing portion 470, which extends through passage 458 to workpiece 22. Loose end 245 of thread 244 feeds through workpiece 22 into groove 450, and feeds around finger 404 into chamber 456, until trailing portion 470 is entirely pulled through workpiece 22 from passage 458, and all of thread 244 is disposed in chamber 456. In preparation for repeating stitch 264, as explained hereafter pusher 306 pushes lower portion 468 into passage 458 to again form the trailing portion 470. Thus,

thread portions

466, 468, 470 are separated as they are loaded and unloaded from receiver 304.

Pusher 306 (FIGS. 3, 4, 15) includes a pusher finger 472, and arm 474, which supports finger 472, and a shaft 476, which supports arm 474. Pusher 306 also has a shaft lever 478, which is fixedly connected to shaft 476, a link 480, which is pivotally connected to lever 478, and a lever 482, which is pivotally connected to link 480.

Pusher 306 also includes a bracket 484, which pivotally supports lever 482, and a bearing plate 486 in which shaft 476 is journaled. Bracket 484 is supported by cantilever beam 54. Bearing plate 486 is supported by receiver 304.

Lever 482 has a follower wheel 488, which rides in track 492 of rotary cam 490, which is fixedly connected to shaft 66. With this construction, cam 490 actuates lever 482 and oscillates finger 472. In operation, as explained previously, pusher finger 472 pushes thread 244 from chamber 456 into passage 458.

As explained before, spreader 294 is an optional member, which may be added to help position near loop 246. Spreader separates near loop 246 and far loop 248 and tends to bow out near loop 246. Spreader 294 (FIGS. 3, 8, 14) comprises an elongate body 308 which is supported by hanger 94 and which has a pointed end portion 310, which is disposed next to needle 92 and which separates near loop 246 from far loop 248 during the forward and upward movement of front chuck 100.

The coordinated operation of thread handling system 18 and its components is explained more fully hereafter with reference to FIGS. 20--25.

Work handling system 20 (FIGS. 1,2,3,13, I4, 26, 27, 28) which has a vertical axis 28 and horizontal axis 26, includes an upper fixed presser 494, an upper needle guide 496, a lower movable presser 498, a lower work feeder 500, and a lower ridge former 502. Upper presser 494 and upper guide 496 are disposed above workpiece 22; and lower presser 498, lower feeder 500 and lower former 502 are disposed below workpiece 22. Work feeder 500 has a stitch adjusting mechanism 504, as explained hereafter.

Upper presser 494 (FIGS. 3, 4, I3, 14) is symmetrically disposed about horizontal axis 26 (FIGS. 26, 28). Presser 494 is a substantially flat plate with a suitably shaped, open, chopped portion 495. Presser 494 has a pair of

leg portions

506, 508, which are substantially parallel to each other and to axis 26 (FIG. 26). Presser 494 is supported by guide 496 (FIG, 14), which is supported by wall 56.

Legs

506, 508 press down on workpiece 22 and cooperate with ridge former 502 to form a ridge 509 in workpiece 22. Ridge 509 is like a node, a hump or a mound, wherein the material is raised to insure the proper passage ofneedle 92 through the workpiece 22.

Needle guide 496 (FIGS. 13, I4) has an elongate arm portion 510 and an end portion 512. End portion 512 has a pair of

finger portions

514, 516. Arm portion 510 is supported by front wall 56 (FIG. 14), and is disposed substantially parallel to axis 24.

Fingers 514, I6 have respective upper faces 518,520 with respective

transverse grooves

522, 524. Groove 522 has opposite sidewalls 526,528 and a bottom bearing wall 530. Bearing wall 530 supports and guides needle 92 as needle 92 enters workpiece 22. Groove 524 also has

opposite sidewalls

532, 534 and a bottom wall 536.

Sidewalls

532, 534 are respectively aligned with sidewalls 526,528.

Lower presser 498 (FIGS. 1, I3, 26, 27) has a presser plate 538 and a presser actuator 540. Presser plate 538 moves vertically substantially parallel to vertical axis 28; and is positioned symmetrically about horizontal axis 26.

Actuator 540 has a bracket support 542 and an enclosure housing 544. Bracket 542 is supported by top panel 42. Housing 544 is supported by bracket 542. Housing 544 has a peripheral wall 546 and an end wall 548. End wall 548 has an opening 550 in which presser plate 538 is disposed. Bracket 542 has

shoulder portions

552, 554, 556, 558, with respective bearings 560, 562,566. Peripheral wall 546 has shoulder portions 568,570 with respective bearings 572,574. Bracket 542 also has a lower bearing 576, which receives drive shaft 64 and an upper bearing 578 for actuator 540 (FIG. 27).

Presser actuator 540 (FIGS. 27, 28) includes a presser rod 580, and a knee lever 582. Rod 580 has an upper end 584, which is fixedly connected to presser plate 538, and a lower end 586, which is connected to lever 582. Rod 580 is slidingly journaled in

bearings

560, 562. Lower end 586 has a transverse pin 588, which is fixedly connected thereto, and a spring 590 which urges rod 580 in an upward direction. Transverse pin 588 has an oversize hole 592 at one end.

Lever 582 has a horizontal arm 594 with a pair of vertically spaced

fingers

596, 598, which engage pin 588; and a vertical arm 600 with a knee plate 602. Lever 582 includes a support shaft 604, which is supported by top panel 42. Rod 580 is pulled vertically downward when lever 582 is rotated counterclockwise (FIG. 27) in response to pressure on knee plate 602.

Work feeder 500 (FIGS. 27,28) includes a feeder foot 606, a cam 608, a vertical displacement linkage 610, and a horizontal displacement linkage 612. Feeder foot 606 has a pivot pin 614, which is pivotally connected to

linkages

610, 612. Feeder foot 606 has two spaced dogs 607 which can move upwardly through slots 609 in plate 538 to engage workpiece 22 to effect the forward and rearward movement thereof relative to needle 92.

Cam 608 has a cam track 616, which receives

linkages

610, 612. Cam 608 is fixedly connected to shaft 64 whereby work feeder 500 is coordinated in operation with needle bar system 16 and thread handling system 18. Cam 608 is supported by shaft 64, which is journaled in bearing 576.

Vertical linkage 610 (FIGS. 27, 28) includes a lever 618, a bell crank 620, and a link 622. Lever 618 is pivotally mounted on a pivot pin 624, supported by bracket 542. Lever 618 has a follower wheel 626, received in cam track 616, and a connector slot 628, pivotally connected to bell crank 620.

Bell crank 620 has a pivot pin 630, which is supported by presser rod 580, a follower head 632, which is received in slot 628, and a free pivot pin 634, which connects to plain link 622.

Link 622 has a lower end 636, which is pivotally connected to free pin 634, and an upper end 638, which is pivotally connected to pin 614.

Feeder foot 606 is movable in a vertical direction together with presser rod 580 and presser plate 538 because bell crank pivot pin 630 is supported by presser rod 580. Cam 608 rotates clockwise as viewed in FIG. 28, whereby feeder foot 606 is displaced in a vertical direction by vertical linkage 610.

Horizontal linkage 612 (FIGS. 27,28) includes a horizontal lever 640, a link 642, a direction changer 644, a lever 646, and a link 648.

Lever 640 is pivotally mounted on a pivot pin 650, supported by bracket 542. It mounts follower wheel 652, running in cam track 616. The free end of lever 640 is pivotally connected to one end of link 642, which at its other end carries a roller 660.

Direction changer 644, changes the direction of feed of the work, is provided with an elongate slot 662, which receives roller 660, and is suitably mounted on changer shaft 664 (FIG. 27), which is supported in bearing 578. Direction changer 644 is tilted at a forward travel angle 666 as shown in FIG. 28 to feed the workpiece 22 forward. Direction changer 644 can also be oppositely tilted by changer shaft 664 and positioned in a reverse travel angle 668, to feed the work backward as explained hereafter. In addition, the size of

angle

666 or 668 can be adjusted to adjust the stitch length as explained hereafter.

Direction changer 644 (FIGS. 27, 28) is connected to a changer lever 670 (FIG. 30), which is fixedly connected to changer shaft 664, for adjusting changer 644 either to its for ward angle 666 or to its reverse angle 668 in order to feed the workpiece 22 toward or away from its stitching position. Changer 644 (FIGS. 1, 2) has a foot pedal 672, mounted on floor panel 34, a vertical rod 674, connected to pedal 672 and a rear lever 676, mounted on rear panel 40 and connected to vertical rod 674. Changer 644 has a horizontal rod 678, which is connected to rear lever 676, and a spring 680, which is connected to horizontal rod 678. Horizontal rod 678 is connected to changer lever 670 (FIG. 30). Spring 680 urges changer 644 to remain oriented at its forward travel angle 666. Thus, foot pedal 672, when not depressed, feeds workpiece 22 toward its stitching position; or when depressed, displaces rod 678 and orients changer 644 to its opposite travel angle 668 and feeds workpiece 22 away from its stitching position.

Lever 646 (FIGS. 27, 28) at its lower end 682 is disposed between changer 644 and link 642 and has a slot 684 that receives roller 660. Lever 646 is pivotally mounted on a pivot pin 686, supported by bracket 542. At its upper end 688, lever 646 is pivotally connected to one end oflink 648.

Link 648 has one end 690, which is pivotally connected to end 688, and its other end 692, which is pivotally connected to pivot pin 614.

Cam 608 rotates clockwise, as viewed in FIG. 28, whereby feeder foot 606 is displaced in a horizontal direction by horizontal linkage 612. Cam track 616 is designed to push feeder foot 606 around a desired unidirectional closed travel path in a vertical plane. Feeder foot 606 coacts with and moves relative to upper presser plate 494 to effect the feed of workpiece 22.

Ridge former 502 (FIGS. 27, 28) includes a plunger 694 with a varying penetration distance 696 above presser plate 538, a plunger guide rod 698, and a plunger penetration adjustor 700 to set the maximum limit of distance 696. Ridge former 502 coacts with upper presser plate 494 to form ridge 509 to insure proper passage of needle 92 through the workpiece 22.

Plunger 694 has a chisel end 702 with a needle groove 704. Groove 704 is oriented parallel to the needle travel path 250. Plunger 694 is guided by the rod 698 and has an integral shoulder pin 706 for engaging adjustor 700.

Plunger rod 698 is slidably journaled in

bearings

564, 566. Plunger rod 698 has a support spring 705, which is supported by shoulder 556. Spring 705 supports shoulder 568 whereby bracket 542 supports housing 544. Plunger rod 698 has a set screw 707, which fixedly connects shoulder 568 to rod 698, whereby rod 698 can move down housing 544 relative to bracket 542. Rod 698 has a lower end 708, which is slidably received in hole 592. Lower end 708 has an integral cap 710 whereby lever 582 can push down pin 588 and engage cap 710 to downwardly displace plunger rod 698. In addition, presser rod 580 can move down a short distance before moving plunger rod 698.

Penetration adjustor 700 includes a pivot link 712 and an adjusting screw 714. Pivot link 712 has an intermediate portion 716, which is journaled on bell crank pin 630. Adjustor 700 also has a right end 720 with an elongate slot 722, which receives shoulder pin 706, and a left end 724, which is pivotally connected to screw 714. Screw 714 is supported by peripheral wall 546. Screw 714 is axially adjustable relative to wall 546 for adjusting penetration distance 696.

Stitch adjuster 504 (FIGS. 29, 30), which adjusts the horizontal stroke of feeder foot 606, includes a support 726, a forward right side bar 728, a reverse left side bar 730, a forward bar regulator 732, a reverse bar regulator 734, and a lock means 736.

Support 726 includes a bottom plate 738, a right side plate 740, a left side plate 742, and a top plate 744. Bottom plate 738 is mounted on top panel 42, and supports

plates

740, 742, 744.

Side plates

740, 742 support a bar shaft 746 and a dial shaft 748. 7

Right side bar 728 has an elongate slot 750 and has a bearing 752, which is journaled on bar shaft 746. Left side bar 730 has an elongate slot 754 and has a bearing 756, which is also journaled on bar shaft 746.

Forward regulator 732, which adjusts forward angle 666 includes a dial wheel 758, which is journaled on dial shaft 748. Wheel 758 has an eccentric portion 760, which is received in slot 750, and a gear portion 762, which engages lock 736.

Reverse regulator 734, which adjusts reverse angle 668, includes a dial wheel 764, which is journaled on dial shaft 748. Wheel 764 has an eccentric portion 766, which is received in slot 754, and a gear portion 768, which engages lock 736.

Lock 736 includes a plunger 770, which is slidably supported by

plates

738, 744. Plunger 770 has a right side toothed arm 772, which is integral therewith and which engages and locks forward gear 762; and has a left side toothed arm 774, which is integral therewith and which engages and locks reverse gear 768. Lock 736 has a spring 776, which is supported by bottom plate 738, which surrounds plunger 770 and which urges

plunger arms

722, 774 in an upward direction against

gears

762, 768.

The operation for making stitch 264 (FIG. 13) by machine is illustrated in assumed steps by FIGS. -25 inclusive.

FIGS, 20-25 inclusive are similar to six successive frames of a motion picture showing the front view of machine 10. It is noted that there is a period of time that expires between each pair of successive figures, in which machine 10 is operating.

FIG. 20 shows the first step in making stitch 264. In FIG. 20, rear chuck 168 supports needle back end 240, thread 244 passes through eye 242, needle front end 238 is received in guide groove 522, needle front end 238 points toward ridge 509 which is formed to insure proper passage of needle 92 through workpiece 22.

Between FIGS. 20 and 21, rear chuck 168 moves counterclockwise through angle 98 and pushes needle 92 through ridge 509. At the same time, needle 92 travels through

needle guide grooves

522, 524 which also insure against lateral flexing of needle 92. Rear chuck 168 supports needle 92 and guides needle front end 238 into front chuck 100, as described hereinabove, it then moves counterclockwise through angle 96 (FIG, 3). Thereafter, front chuck 100 moves clockwise through a small backup angle to slacken thread 244 and to bow near loop 246 and far loop 248 away from needle 92.

Between FIGS. 20 and 21, in addition, when rear chuck 168 passes needle 92 to front chuck 100, rear chuck detent 206 and front chuck detent 138 are unlocked by respective stop bars 230, 162. Between FIGS. 20 and 21, front chuck 100 moves counterclockwise while holding needle front end 238. As front chuck 100 lifts away from needle guide 496, spreader 294 separates near loop 246 from far loop 248 (FIG. 14).

FIG. 21 shows the second step in making stitch 264. In FIG. 21, front chuck 100 holds needle front end 238, near loop 246 extends from workpiece 22 to eye 242, far loop 248 extends from workpiece 22 to eye 242, needle back end 240 is disposed in guide front groove 524, and finger 312 is in a stationary condition.

Between FIGS. 21 and 22, finger 312 travels along its travel path 320 between near loop 246 and needle 92 pulling near loop 246 clockwise until near loop 246 is engaged by hook 360. As near loop 246 is held by hook 360, gripper 300 pulls near loop 246 in an axially inward direction toward thread puller 302. In addition, between FIGS. 21 and 22, front chuck I00, rear chuck 168 and needle 92 are lifted, and their axis 24 is lifted through offset 254 so that needle back end 240 is disposed above ridge 509.

FIG. 22 shows near loop 246 held by hook 360 and gripper 300 so that near loop 246 is disposed next to thread puller 302. FIG. 22 also shows finger 404 preparing to engage near loop 246. In FIG. 22, gripper 300 grips a portion of near loop 246 between workpiece 22 and hook .360 to prevent a tension force entering stitch 264 from near loop 246 in order to avoid puckering of the seam 274. In FIG. 22, chucks 100, I68 remain stationary.

Between FIGS. 22 and 23, finger 404 pulls its adjacent portion of near loop 246 into receiver 304 while gripper 300 still grips its adjacent portion of near loop 246. Between FIGS. 22 and 23, in additon, chucks 100, 168 remain stationary.

FIG. 23 shows upper portion 466 of the loose end 245 of the thread 244 disposed in groove 450 and lower portion 468 of the loose end 245 of the thread disposed in chamber 456. In FIG. 23, finger 312 moves counterclockwise and passes

chucks

100, 168. FIG. 23 also shows the upper portion 466 of the loose end 245 of the thread 244 being fed by the trailing portion 470 of the loose end 245 of the thread 244 (FIG. 18), which is being pulled through workpiece 22. In FIG. 23, chucks 100, 168 remain stationary.

Between FIGS. 23 and 24, front chuck 100 moves clockwise, needle 92 travels above ridge 509, and rear chuck 168 receives needle 92 back again from front chuck 100. Between FIGS. 23 and 24, finger 312 also moves in a counterclockwise direction.

FIG. 24 shows needle 92 disposed above ridge 509, shows front and

rear chucks

100, 168 holding needle 92, and shows their chuck detents 138,206 unlocked by their respective stop bars 162, 230. In FIG. 24, finger 312 is shown back at its original stationary position.

Between FIGS. 24 and 25, rear chuck 168 locks onto needle back end 240, and rear chuck 168 and needle 92 rotate clockwise through angle 98. Pusher finger 472 pushes lower portion 468 of the loose end 245 of the thread 244 from chamber 456 to passage 458 so that lower portion 468 is positioned in passage 458 and becomes the trailing portion 470 of the loose end 245 of the thread 244 in preparation for repeating stitch 264 (FIG. 18).

FIG. 25 shows ridge 509, which contains understitch portion 266 of stitch 264 (FIG. 13). FIG. 25 is the last step in making stitch 264 and is very similar to the first step, which is shown in FIG. 20. In order to form the overstitch portion 268 of stitch 264 (FIG. 13), workpiece 22 is first moved relative to needle 92 by work feeder 500, and then the above described steps of FIGS. 20, 21 are repeated. In order to make another stitch 264, the steps of FIGS. 2125 inclusive are repeated.

The operation of handling workpiece 22 by machine is explained thereafter. Work handling system is designed to enable the operator to sew forward, backward. or to bar tack. The following is a typical sequence of steps in the operation of work handling system 20:

I. To allow the workpiece 22 to be placed in machine 10, the operator moves knee plate 602 toward right wall panel 38 thereby rotating knee lever 582, and forcing down transverse pin 588, presser rod 580, presser plate 538, pin 630, crank 620, link 622 and foot 606 through a first, initial, downward distance in order to place presser plate 538 flush with enclosure end wall 548 for easier loading of workpiece 22, and, if desired, also through a second, additional downward distance. The second distance is in the range of one to eight times the first distance. In the movement through the second distance, knee lever 582 and transverse pin 588 also move down plunger support rod 698 and housing 544 relative to bracket 542 by compressing spring 705;

. After workpiece 22 is properly positioned for sewing, knee lever 582 is released and workpiece 22 is then clamped between presser plate 538 and upper presser 494;

. In the operation of work handling system 20, cam 608, which rotates clockwise in FIG. 28, actuates lever 618 about pin 624, thereby rotating crank 620 about pin 630, which is fixedly attached to spring-loaded presser rod 580. Crank 620 rotates and lifts feeder foot 606 through link 622 until foot 606 clamps workpiece 22. Cam 608 continues to drive lever 618, but since feeder foot 606 is already bearing against workpiece 22, the over-travel is taken up by forcing pin 630 in a downward direction and by forcing presser rod 580 against spring 590;

4. As pin 630 moves downward. presser rod 580 and link 712 also move downward thereby pulling downward pin 706 and plunger 694. In this way, plunger 694 moves up and down during each sewing cycle to form ridge 509 in workpiece 22in order for needle 92 to easily pierce workpiece 22;

5. At this point in the sequence of operation, with feeder foot 606 clamping workpiece 22, and with plunger 694 and presser plate 538 in their downward position, cam 608 rotates lever 640 about pin 650 thereby causing roller 660 to move back and forth in slot 662 of direction changer 644 and in slot 684 of lever 646;

6. If direction changer 644 is positioned in a vertical plane, roller 660 will move up and down in this vertical plane and lever 646 will have no transverse motion so that this position is used for bar tacking. When direction changer 644 is rotated to the front and positioned at angle 666, as shown in FIG. 28, lever 646 and link 648 will move thereby causing feeder foot 606 to index workpiece 22 to the rear, or to the left in FIG. 28;

7. As cam 608 continues to rotate, lever 618 moves forward and bell crank 620 rotates clockwise, as shown in FIG. 28, thereby releasing the over-travel taken by springloaded rod 580. In this way, presser plate 538 moves upward and clamps workpiece 22 just as feeder foot 606 is pulled downward by link 622;

8. As the stored over-travel is released, pin 630 moves up ward lifting link 712 and plunger 694. Feeder foot 606, while in its downward position, is moved forward, or to the right in FIG. 28, to begin its next cycle; and

9. The size of penetration distance 696 determines the size of ridge 509, which determines the depth of stitch penetration. By moving adjusting screw 714, pivot link 712 can be rotated about pin 630 whereby plunger 694 can be raised or lowered.

In summary, this invention provides a floating-needle, shortthread, sewing machine, which can produce fell stitching, which can sew from one side of the workpiece only, and which can fell a wrinkle-free seam along a seam line curved in three dimensions, such as a coat undercollar seam.

While the present invention has been described in a preferred embodiment, it will be obvious to those skilled in the art that various modifications can be made therein within the scope of the invention. It is intended that the appended claims cover all such modifications.

Iclaim:

1. In a sewing machine having a work stitching position and mechanism for feeding work to be stitched to and from said position, the combination of:

opposed rotary needle chucks;

a curved needle with a short thread for projection by said chucks along a curved path of travel through work to be sewed;

means alternately connecting said chucks to said needle;

and

means for operating said mechanism to move said work to and from said position.

2. In a sewing machine having a work stitching position and mechanism for feeding work to be stitched to and from said position, the combination including;

a first needle chuck rotatable about an axis of rotation;

a second needle chuck opposed to said first needle chuck;

a curved needle alternately supported by said first and second chucks and traveling in a forward curved travel path and in a return curved travel path; and

means for operating said feeding mechanism to move said work to and from said position.

3. The machine as claimed in claim 2, and including:

means supporting said first and second chucks having means moving said chucks through an offset distance transverse to said paths for offsetting the return path from the forward path.

4. The machine as claimed in claim 3 wherein said last named means includes a movable support member, and means for moving said member in timed relationship with the movement ofsaid chucks.

5. The machine as claimed in claim 2, in which:

said first needle chuck and opposed second needle chuck have a common axis of rotation and are rotatable individually about said axis within respective spaced travel angles for reciprocating in forward and return travels said curved needle, and said needle has a short thread for passing said needle and thread in said forward travel through a workpiece disposed between the first and second needle chucks.

6. The machine as claimed in claim 5, and including:

means for supporting said first and second needle chucks and for lifting said first and second needle chucks and said needle above the workpiece on the return travel of the needle.

7. The machine as claimed in claim 2, wherein said first and second needle chucks each comprises:

a chuck head for gripping said needle;

a shaft for supporting said chuck head;

means supporting said shaft; and

means for rotating said shaft and said chuck head.

8. In a sewing machine having a work support and a work a pair of opposed rotary needle bars and a curved needle having an eye between its ends and having a short thread extending through said eye, said needle bars alternately supporting said curved needle for conveying said needle along a curved path of travel, said thread having a fixed end and a loose end disposed on opposite sides of the eye;

means for moving at least one of said needle bars to pass said needle through work to be stitched and to form a loop of thread on each side of said needle;

a looper movable along a first path of travel extending from said needle in a direction away from said needle for means disposed adjacent to said conveying means for guiding said finger along said second path of travel and in which;

said thread receiving means includes an elongate member having a chamber for receiving said portion of thread from said thread pulling finger and having a passage into which said portion of thread is transferred from said chamber; and

means for transferring said portion of thread from said chamber into said passage.

15. The machine as claimed in claim thread receiving means includes:

an elongate member with an outer surface having a groove for guiding said portion of said thread disposed along said 11, in which said 1 pulling one of said loops along said first path oftravel; 5 secQnd P of travel whlle bemg fed to said thread a thread puller having a second path of travel extending Pullmg finger;

from said first path of travel in a direction away from said a Chanlber PP l f to said 8 for guldmg 531d first path for engaging said first loop positioned in its path Portion f a1d lhfead sposed along said second path of of travel by said looper for pulling said loose end of said travel whlle bemg from said {mead punmg fingeriaPd thread through Said Work and along said Second path of a passage disposed ad acent to said chamber for receiving travel. said portion of said thread from said chamber after said me 8 f a f f t 10 d portion of said thread has been fed to said chamber.

l gi g g lgi s z g z g g igf z 16. The machine as claimed in claim 9, in which said actuatpreventing tensioning of the fixed end of said thread relamg l p for Sald l pullerlncludesl tive to Said work; and a timing belt connecting to said thread puller for pulling said actuating means for actuating in a coordinated and timed threadpuuer alorlg Sald secolld P i Oftravel;

operation Said p of needle bars Said looper Said thread a track disposed ad acent to said timing belt for guiding said puller and Said feeding means thread puller along said second path oftravel. 9 In a Sewing machine the combination of: 17. The machine as claimed in claim 9, in which said feeda pair of opposed needle bars and a curved needle having an eye between its ends and having a short thread extending through said eye with a fixed end and a loose end, said bars being adapted to alternately support said needle to pass said needle and thread along a curved path of travel through work on at least one movement of said needle relative to said work;

a looper movable along a first path of travel extending from said needle in a direction away from said needle for engaging and pulling a portion ofsaid thread;

means including a holder disposed adjacent to said first path of travel for receiving and holding said portion of said thread;

a thread puller having a second path of travel extending from said holder in a direction away from said holder for engaging said portion of said thread and for pulling the loose end of said thread through said work and along said second path of travel;

means for feeding said work into and out of the range of operation of said needle; and

actuating means for actuating in a coordinated and timed operation said pair of needle bars, said looper, said thread puller, and said work feeding means.

10. The sewing machine as claimed in claim 9, in which:

said holder includes a hook portion for receiving and holding said portion of said thread.

11. The machine as claimed in claim 9 and including:

means for receiving said portion of thread from said thread puller disposed alongside said second path of travel.

12. The machine as claimed in claim 11, in which:

said means for receiving said portion of thread from said thread puller includes an elongate chamber for receiving said portion of thread and an elongate passage disposed alongside said chamber for storing said portion of thread.

13. The machine as claimed in claim 12, in which said ing means includes:

means supporting and positioning the work in said curved path of travel between said needle bars; and

means guiding said needle along said curved path of travel having a first guide portion disposed between one needle bar and said work for guiding said needle into said work and having a second guide portion disposed between said work and the other needle bar.

18. The machine as claimed in claim 9, in which said feediing means includes means disposed above said work pressing on said work for supporting and guiding said work, said pressing means having a pair of spaced leg portions disposed at an angle to the path of travel of the needle, and means pressing up on said work and forming an angular ridge in the unpressed portion of the work disposed between said leg portions.

19. The machine as claimed in claim 9, in which said feeding means includes means supporting and positioning the work in said curved path of travel between said needle bars, including a first member disposed above said work adjacent to said pair of needle bars and pressing on said work, and a second member disposed below said work and pressing on said work and against said first pressing member, said second pressing member being selectively movable away from said first pressing member.

20. The machine as claimed in claim 19, in which said lower pressing member is enclosed by a housing disposed below said work, said housing being displaceable relative to said upper presser member and also separately displaceable relative to said lower presser member.

21. The machine as claimed in claim 19, in which said feeding means includes means disposed below said work adjacent said lower presser member ,and displaceable relative to said upper presser member in an axial direction for forming a ridge in said work.

22. The machine as claimed in claim 9, in which said feedreceiving means includes means for pushing said portion of thread from said chamber into said passage.

14. The machine as claimed in claim 18, in which said thread puller includes:

a thread pulling finger movable along said second path of travel for pulling said portion of thread; means connected to said thread pulling finger for conveying said finger along said second path of travel; and

ing means includes:

means supporting said workpiece having an axis along which said work is advanced in a forward direction or in a reverse direction;

a work feeding mechanism including a feeder foot engaging said work, a first actuator connecting to said feeder foot for moving said feeder foot in a direction substantially at right angles to said axis, and a second actuator connecting to said feeder foot for moving said feeder foot in an axial direction;

direction changing means connecting to said second actuator and controlling said feeder foot for advancing said feeder foot in a forward direction or in a reverse direction along said axis; and

stitch adjusting means connecting to said direction changing means for controlling the length of said stitch.

23. In a sewing machine, the combination of:

a curved needle having an eye between its ends and having a short thread extending through said eye;

a first needle chuck and a second needle chuck opposed to said first chuck;

means reciprocating said first chuck for passing said curved needle along a curved line of travel through work and means reciprocating said second chuck for pulling said needle along said curved line of travel out of and away from the work; and

a two-stage thread puller for pulling the thread from the work along a first path of travel in a direction away from said needle and thereafter for pulling the thread further along a second path of travel in a direction transverse to said first path of travel.

24. In a sewing machine having a work stitching position and mechanism for feeding work to be stitched to and from said position, the combination of:

alternately operating opposed needle bars;

a curved needle with a thread having a fixed end and a loose end;

means to alternately connect the needle with each needle bar for moving said needle along a curved path of travel;

means for supporting a work having a seam on one side and for positioning said work between said bars and in said travel path so that the needle and thread pass into the work and under the seam and out of the work on the same side of the work;

means for pulling the loose end of the thread out from the work and for conveying the loose end back across the seam in each stitch in the formation of a succession of stitches; and

25. in a sewing machine, the combination of:

a first needle bar and a second opposed needle bar having a common axis of rotation and a curved needle alternately supported by said needle bars;

means supporting and rotating said needle bars about said axis for movement of said needle along an arcuate path of travel;

means supporting work, said means being disposed radially outwardly from said arcuate path of travel; and

means forming a ridge in said work and positioning said ridge in said arcuate path of travel between said first and second needle bars, said ridge forming means being disposed radially outwardly from said arcuate path of travel of said needle.

26. The machine as claimed in claim 9, and including:

means for effecting relative movement between said needle and said work feeding means whereby said needle may be passed forwardly through the work into one bar and rearwardly over the work into the other bar.