Patent GB-955101-A (GB)
Title: Improvements in or relating to sewing machines
IPC: D05B15/04
Filed: 1960-08-02
Abstract: 955,101. Sewing. BRITISH UNITED SHOE MACHINERY CO. Ltd. Aug. 2,1960 [Aug. 5, 1959, No. 26677/60. Heading D1G. In a loop lock-stitch sewing machine for attaching outsoles to shoe welts, the work is fed continuously along a curved path by a combination of feed by jaws and needle feed, a work support and presser foot constituting a pair of work-feeding jaws being mounted on a carriage, a curved hooked needle and a curved awl being mounted on a second carriage, and said carriages being mounted for pivotal movement about a common axis. Work feed, work holding.. Figs. 3, 4, 9. A U- shaped work support 10 is secured to a carriage 28 pivoted on a shaft 30 inclined at 60 degrees to a horizontal line 31 at the level of a worksupporting surface 26 of the member 10. A line 32, normal to shaft 30, bisects the angle between line 31 and the curved, front, shoe upper-engaging surface 34 of member 10. The presser foot 12 is carried by a lever 294 pivoted at 296 to the carriage 28. The needle 2 and awl 4 are arc arranged to oscillate about a pin 22 mounted in a carriage 52 also pivoted on shaft 30. Said carriages are oscillated by connections from a cam 80 on a rotary shaft 18, the jaws feeding for approximately 310 degrees of rotation of shaft 18, and the awl and needle feed commencing near the end of the jaw feed and extending for approximately 160 degrees. A groove 78 in cam 80 is engaged by diametrically opposed rollers 82, 84. Roller 82 is carried by an arm 86 rigid with a shaft 88 parallel to shaft 30. An arm 94, also rigid with shaft 88, has a forked outer end pivoted at 95 to a pair of bars 96. A bar 98 is pivoted at 106 to carriage 28 and at 100 to the bars 96. An extension of bar 98 passes slidably through a pin 107 journalled in one arm of a member 108 slidably mounted on a fixed rail 110. Roller 84 is carried by one arm of a bell crank lever 128 journalled on shaft 88. The other arm of lever 128 is pivoted at 126 to a pair of bars 114. A bar 116 is pivoted at 120 to carriage 52 and at 122 to the bars 114. An extension of bar 116 passes slidably through a pin 129 journalled in a second arm of member 108. The pivots 95, 106,120,126 are hollow and can be moved into alignment for a pin to be inserted temporarily therethrough. The arrangement enables identical movement to be imparted to the carriages 28, 52, the extent of which movement being determined by the distance of the pins 107, 129 from the shaft 88, as adjusted by shifting member 108 along rail 110 via a link 131 and a lever connected thereto. Stitch forming. The hooked needle 2 and awl 4, Fig. 4, are fixed to members 60 and 58 respectively which are pivoted about the axis of pin 22 mounted in carriage 28, and are adjustable along said axis to align the needle and awl. Member 60 is connected by a link 64 to one arm of a lever 146 pivoted at 148, the other arm carrying a roller 152 engaged with a cam 154 on shaft 18. One arm 156 of a lever pivoted at 148 carries a roller 158 engaged with a cam 160 complementary to cam 158, and the other, and resilient, arm 162 bears against a stud 164 screwed into lever 146, whereby the rollers are biased against the cams. Member 58 is connected by a link 168 to a lever 172 which is pivoted at 148 and carries a roller engaging a cam on shaft 18. A lever pivoted at 148 has an arm 173 carrying a roller engaged with a complementary cam, and a resilient arm 174 abutting a stud 176 screwed into lever 172 to bias the rollers against the cams. A finger 134, Fig. 3, adapted to insert a loop of locking thread 74 into a loop of needle thread withdrawn from the work, is carried by an arm 284 pivoted at 286 to an arm 288 pivoted at 290 to the carriage 28. Arm 288 is connected by a pin 292 to the lever 294 which carries the presser foot 12 and is pivoted at 296 to the carriage 28 in alignment with the pivot 290. The arrangement is thereby such that the finger 134 rises and falls with the presser foot 12. Arm 284 is connected by a link 298 to an arm 300 pivoted at 302 to arm 288. Arm 300 is connected by a link 304 to one arm of a lever 306 pivoted at 308, the other arm carrying a roller 309 spring-biased by a plunger 312 into engagement with a cam 310 on a rotary shaft 20. A finger 135, adapted to retain the locking thread loop inserted by finger 134 when the latter withdraws, is carried by an arm 317 fixed to a crank 320 on a shaft 322 journalled on lever 294. Shaft 322 is oscillated via a link 326. A finger 138, Fig. 13, adapted to spread the needle thread loop for insertion of the locking thread loop, is carried by a rotatable spindle 256. A crank 258 on the latter is connected by a link 260 to a lever 266 which is pivoted at 268 and carries a roller 270 biased into engagement with a cam 272 on shaft 20 by a spring 264 interposed in link 260. A finger 136, adapted to remove the needle loop from the needle before a take-up acts to set both loops within the work, is carried by a crank 274 on a rotatable spindle 276, a crank 270 on which carrier a roller 280 engaged in a groove in a cam 282 on shaft 20. The needle thread take-up 14, Fig. 14, is in the form of a bell crank lever pivoted at 177, one arm carrying a roller 180 engaging a bight of needle thread 72, and the other arm being connected by a linkage 182,184,190,192 to one arm of a threearmed lever 194 pivoted at 196. A second arm of lever 194 carries a roller 198 engaged with a cam 200 on shaft 18. A lever 202, pivoted at 196, carries a roller 204 engaged with a cam 206 complementary to cam 200, and is resiliently connected by a bolt 208 and spring 210 to lever 194 for biasing rollers 198 and 204 against the cams. A needle thread pull-off arm 216, Figs. 14,15, is fixed to an oscillating shaft 219 and acts between thread guide portions on a measuring arm 228 fixed to a sleeve 229 which is journalled on shaft 219 and is connected for movement with the presser foot 12. A crank 220 on shaft 219 is connected by a link 222 to the third arm of lever 194. An oscillating lever 240, pivoted at 242, carries on its respective arms blocks 236 and 238 which co-operate with a fired roller 230 and a fixed block 234 to effect alternate thread locking on opposite sides of the pull-off arm 216. A toothed arm on lever 240 co-operates with a similarly toothed arm 244 on a rotary shaft 218 aligned with shaft 219. A crank 249 on shaft 218 has a resilient connection with a link 250 afforded by a pair of compression springs 251. Link 250 is connected to a lever 252 which is pivoted at 196 and carries a roller 254 engaging a groove in a cam on shaft 18. The needle looper 6, Fig. 11, is secured to a horizontal link 372 slidable in a groove 377 formed in the machine frame and connected to one arm of a lever 364, the other arm of which carries a roller 360 engaged in a groove 358 of a cam on shaft 18. A second horizontal link 374, pivoted at 376 to link 372, is connected to one arm of a lever 366, the other arm of which carries a roller 362 engaging a groove 359 of a cam on shaft 18. Needle guides, stitch forming. An oscillating needle guide 61, Fig. 17, pivoted about the axis of pin 22, is connected by a link 327 to one arm of a lever 328 pivoted at 330, the other arm carrying a roller 332 engaging a groove 334 of a cam 336 on shaft 18. An arm 337 fixed to lever 328 is connected by a link. 338 to arms 340, 352 pivoted at 342 and 354 respectively. An arm 356 rigid with arm 352 carries a roller 144 positioned between thread guides 357 to act as a locking thread pull-off. When roller 144 is acting, the thread is locked between discs 348 drawn together by a spring-biased stud 346. An arm 344, rigid with arm 340, acts on stud 346 to release the thread when roller 144 is not acting. Application 23478/10, Specification 532,026, 558,431, 804,854 and 946,671 are referred to