Patent GB-721758-A (GB)
Title: Improvements in or relating to toe lasting machines
IPC: A43D21/12
Filed: 1952-01-02
Abstract: 721,758. Lasting machines. BRITISH UNITED SHOE MACHINERY CO., Ltd. (United Shoe Machinery Corporation). Jan. 1, 1953 [Jan. 2, 1952], No. 110/52. Class 17 (1). In a machine for conforming the toe portions of already-pulled-over shoes to the shapes of lasts therein having wipers 2, power means for effecting upwiping and then in-wiping, a clamping arrangement (for positioning the shoe relatively to the path of the wipers) including means to engage the toe portion of the shoe bottom and a device for engaging the top of the forepart of the shoe, means for restraining the upper during wiping, and a heel rest which is movable widthwise, to cater for right and left shoes and different styles, and lengthwise, the rest is guided in a predetermined direction as it is moved lengthwise and the rest guide is adjustable to vary the direction in accordance with the particular last. The wipers are bodily movable together widthwise of the last in response to pressure of the shoe during heightwise movement to adjust themselves to the shoe, but such movement is prevented during inwiping. The power means effecting upwiping comes into effect when the shoe is engaged by the rest, and during the wipers move heightwise to increase the inwiping pressure on the upper margin, then away to reduce the pressure, and finally toward the last again to increase the pressure once more. The shoe is located by engagement with an adjustable plate 4, and a retarder 18 which clamps the margin of the upper on the wipers 2, and at the beginning of a cycle is clamped by means of a toe rest 22, a heel rest 24 then being engaged with the heel. The heel rest includes a padded V-shaped member 26 with a stem which is adjustable angularly about an axis lengthwise of the shoe in a block 32, being clamped by a screw. Segmental members 36, Fig. 3 (not shown), are mounted in curved recesses in the sides of block 32 and in guideways 38 in plates 40 on a holder 42 supported on a slide 44. Screws 46 threaded in the members 36 extend through slots 48 in plates 40 and are turned by hand wheels 50, so that the block 32 and heel rest 24 may be adjusted and clamped about an axis widthwise of the shoe. The parts are adjusted about an axis heightwise of the shoe on a stem 52 and the holder 42 extending into a bore in the slide 44, being clamped by a finger 54. Slide 44 is adjustable laterally on a guide 64 fast on a plate 66, and clamped by a thumb screw 68. A roll 78 on plate 66 lies in a slot 80 in a block 70 so that the plate moves with the block in movement lengthwise of the shoe imparted by rods 82 having telescopically adjustable parts 84, 86. The movement imparted to the heel rest by block 70 is adjusted by means of a guide bar 88 adjustable about a stud 96 and clamped by a handwheel 102 on a bolt 100, extending through a slot 98 in plate 72. The bar 88 is set for a particular style of shoe by means of a mark 104 on the bar and scales for right- and left-hand shoes on plate 72, the operator having a chart indicating the scale numbers for different styles. An additional widthwise adjustment of the heel rest, for the "swing" of the last is made by moving slide 44 along guide 64, right- and left-hand scales being provided. The wipers 2 are detachably mounted in holders 106 guided laterally of the shoe in a curved path on a carrier 108, which is moved lengthwise of the shoe on links 118 by a lever 120 pivoted at 122 and controlled by a cam path 126 on shaft 128. The carrier may be swung upwardly by means of a path cam 138 through roller 136, arms 134 and 130, and links 118. The wipers are closed inwards by forward movement of a slide. 140 through a path cam 143 and parts 142, 144, 146, 148, as in Specification 520,194. The slide 140 is connected to the holders 106 by yieldable link mechanisms similar to those described in Specification 573,358 and having parts 150, 152, 154, 156, 158, 160, 170, 172. A pin 174 on each ring 172 extends into a slot 176 in an adjusting slide 178 guided widthwise of the machine. The slide is adjusted by a rack bar 180 engaging a pinion 184 on a shaft 186, a disc on the shaft having a pin lying in a slot in the slide, and in the correct positions a spring-pressed retaining member enters one of three recesses in the rack bar. The wipers are preliminarily adjusted towards and from each other by turning the rod 148 to move the slide 140 relatively to the rod by.a mechanism similar to that described in Specification 573,358, a,thread on the slide being engaged by a thread 198 on the rod which is turned by means of a pinion 200 thereon, a meshing pinion 202 keyed to a rod 206 which is turned through a worm gear 216 thereon, a worm 218, shaft 220, and gears 224, 226 by a hand wheel 232. To ensure that the wipers apply substantially equal pressures during upwiping the carrier 180 is swung widthwise in response to pressure on one side. For this purpose the rod connecting the carrier 108 to the lever 120 has a convex portion 238 of larger diameter which engages the bushing 236, and to facilitate this swinging links 118 are pivotally connected by pins 240 to blocks 242 pivotally connected by pins 244 to the carrier and arms 130. To prevent this lateral movement during in-wiping, so that the wipers move equally inwardly, rolls 246 engage cam plates 248 on the carrier. The rolls are urged towards the carrier by a light spring 254, movement being limited by a screw 256, which permit lateral movement during up-wiping. Movement of the carrier for inwiping brings the inclined faces 262 to engage the rolls and force them against springs 254, flanges 264 engaging member 252 to centralize the wipers. To ensure equal inward movement of the wipers the slide 140 is moved to engage nipples 114 with the end of slots 116 in the carrier, and pins 170 with the ends of slots 160. The wipers are moved for a first inwiping as in Fig. 14 to prevent severe action on the upper and then retracted and moved for a second inwiping as in Fig. 15. A movable wiping plate 266 bridges the ends of the wipers. The adjustable fingers 20 of the retarder 18 are supported from a bar 284, prevented from turning about the rod 282, and adjusted lengthwise of the shoe by movement of arms 286 through a screw 292, 294, the arms being clamped by screw 300. The fingers are secured by latch members 304, Fig. 10 (not shown), normally urged by springs 312 but released by movement of arms 314. Bar 284 is pivotally supported on an arm 316 loose on a rock shaft 318 and is adjusted to position the retarder heightwise by means of a hand wheel 336. An arm 322 integral with 316 is connected to one arm 326 of a three-armed lever 328 fast on shaft 318. The retarder is adjustably urged downwardly by a spring 356 through bell-crank 346 link 340 and arm 338 on shaft 318, and by spring 358 connected between the lever 328 and a lever 362 adjustable to vary the tension. The retarder is lifted co-ordinately with upwiping by a cam 354 acting on a roll 352 on the bell crank 346, the timing being adjusted by a screw 364 threaded in an arm 366 integral with 338 which spaces the roll 352 from the cam. During this movement the retarder is moved lengthwise by a roll 372 on bar 284 engaging a slot 370 in an adjustable cam plate 368, an eccentric 382 allowing variation of the initial position of the retarder independently of cam plate 368. The hold-down 390 is pivotally mounted on a pin 402 on a slide 404 urged by spring 410. The initial heightwise position is adjusted by a bell crank 416 having one arm 420 supporting the slide and the other controlled by screw 426, 428. The hold-down is withdrawn by means of cam 354 through a third arm 432 on lever 328, nut 434, rod 436, and an arm projecting from slide 404. Shaft 128 is driven by motor 450 through clutch 448, 452, shaft 446, worm 444, and gear 442. A yoke 456 connected to the hub of member 452 is used to withhold that member from the member 448 against the spring 454 to stop operation. A catch 460 on an arm 458 which swings with the yoke is normally engaged by a shoulder 461 on a block 462 so that the clutch parts are disengaged. An arm 464 carrying block 462 is pivoted to one arm of a bell crank 466, the other arm carrying a roll 470 engaging a path cam 472 on shaft 128. Spring 474 urges arm 464 to hold latch 460. Arm 464 extends through a slot in a bar 476 and has a pin 478 engaging a shoulder 480 on the bar, which is pivoted to an arm 482 on rockshaft 484, a spring 486 urging the arm against a stop 488. The end of bar 476 is held against a screw 490 by a spring 492. Depression of the treadle 494 fast on shaft 484 moves bar 476 forwards, swinging arm 464 to disconnect the latch 460 to permit spring 454 to engage the clutch parts. To stop the machine arm 464 is lowered by cam 472 acting on the bell crank 466, disengaging pin 478 from shoulder 480, so that spring 474 swings the arm to connect the latch, the arm 464 then lifting to swing the yoke 456 so as to disengage the clutch. Cam 472 is formed so as to stop the machine at the end of the cycle, and when the wipers have completed their second inward movement, so as to allow time for the cement to set while the upper is under the pressure of the wipers, the machine being restarted to complete the cycle by depression of the treadle. The machine may be prevented from stopping before the end of the cycle by means of a spring-urged bell crank 496 with one arm 498 carrying a roll 500 engaging a cam 502, and the other arm 506 forked to guide a slide 508 connected by rod 512 and link 514 to a lever 516 pivoted at 518 and engaged in one of two positions 522 by a spring-pressed pin 520. In its lower position, Fig. 16, slide 508 is against a pin 524 on arm 464. Before cam 472 is effective to stop the machine before the end of the cycle cam 502 swings bell crank 496 so that the slide 508 engages pin 524 and swings arm 464 which then does not engage the latch when raised by cam 472. Cam 502 does not interfere at