Patent GB-608176-A (GB)
Title: Improvements in or relating to shoe upper conforming machines
IPC: A43D21/16
Filed: 1946-02-18
Abstract: 608,176. Upper-conforming machines. BRITISH UNITED SHOE MACHINERY CO., Ltd. (United Shoe Machinery Corporation). Feb. 18, 1946, No. 4960. [Class 17 (i) ] A gripper is associated with a holddown adapted to engage the inside near its edge, hydraulic means first lowering the holddown and then raising the gripper, to pull the upper, with the holddown as a fulcrum. The inner jaw 88 of the gripper Fig. 5, is carried by an hydraulic cylinder 92 mounted in the machine to be capable of vertical movement about a horizontal pivot. The movable jaw 98 is pivoted to the cylinder at 96 and connected to a piston 104. Also in the cylinder are a fixed partition 202 and a piston 206 connected by a link 208 to a lever 210 pivoted on the cylinder and jointed at 222 to the holddown 214. The latter normally is raised relatively to, and held towards the cylinder by a spring 236. When pressure fluid is admitted by a pipe 110 below the partition 202, the piston 104 is lowered to close the movable jaw 98 yieldingly through a rod 196 and springs 190. Fluid then passes through the partition by a grooved pin 240 to raise the piston 206. This first lowers the holddown yieldingly through springs 232 and then raises the cylinder about the joint 222. In the operation of the machine, the gripper is moved outwardly of the shoe bottom, to a position just clear of the inside edge so as to spread the upper margin and prevent premature adhesion of cement on it, before the gripper is closed. Provision is made for adjustment of the gripper cylinder heightwise, lengthwise and widthwise of the shoe. The machine shown comprises a pair of curved grippers for operating on the upper at each side of the shoe at the junction of the ball and shank, and a pair of main and auxiliary wipers 256 and 320 for wiping the upper after pulling, from the toe end to a position rearwardly of the ball line, Fig. 3. The operation of this machine is so timed that after a shoe has been positioned between adjustable side gauges 18 with its bottom in contact with a holddown 14, admission of pressure fluid to a cylinder 48, Fig. 2, raises a toe rest 42 yieldingly to clamp the shoe, and to a cylinder 166 moves the two grippers outwardly of the shoe. This is effected by a first depression of a treadle. A second depression of the treadle starts an automatic cycle of operations during which pressure fluid is admitted to the cylinder 92 to close the grippers, operate the holddowns 214 and raise the grippers to a cylinder 28 to close the wipers yieldingly, and to a cylinder 510, Fig. 20, to rotate a timing drum 506 which is effective to start and stop the operations of the cycle at the correct times. The auxiliary wipers are timed to engage the shoe when the pull of the grippers is completed, followed by the main wipers which act to move the holddowns inwardly of the shoe. The grippers then release the upper, the holddowns are raised and the grippers raised still higher and the main and auxiliary wipers complete their stroke. At this time the holddown 14 is released by a connection to the wipers, so that the toe rest is free to rise to press the upper against the wipers. Finally, the timing drum ceases return of the parts to starting position. The shoe, released by lowering of the toe rest falls into a receiver 370, 376, Fig. 2. The main wipers are electrically-heated, flexible plates which are supported against flexure at spaced points by screws 312, 314. They have a small component of movement toewardly and are cut away at 319 to clear the lasting tacks at the toe. They are andjustable relatively to the shoe and are swung by the piston of the cylinder 28 through linkage 278, 270, Fig. 2, and 268, 260, Fig. 3, an arm 296 moving with the lever 270 controlling the release of the holddown 14 through a lever 12. Motion is transmitted yieldingly from the wipers 256 to the auxiliary wipers 320 through springs 336 and levers 322. The latter wipers have a substantial component of movement toewardly. They slide in contact with the main wipers and comprise an upper plate 321, Fig. 18, and a more flexible lower plate 346 the contour of which may be varied by a wedge 352 and screw 358. The grippers are raised higher after they have opened, by means of lever 360 acted on by springs 362 connected to the main wipers. The hydraulic system for operating the machine comprises a reservoir 384, Fig. 20, with a constantly-running pump 386 and a valve 440 which may return the oil to the reservoir or pass it to a pressure chamber 382 which can supply oil to the cylinders of the toe rest and gripper spreading mechanism, the gripper operating mechanism, the wiper mechanism and the timing drum by valves 398, 500, 502 and 518 respectively. The first depression of the above-mentioned treadle operates the valves 440 and 398 to supply fluid to the chamber 382 and to clamp the shoe. The second depression opens the valve 518 to effect the automatic cycle of operations. The valves are all generally similar, comprising a sleeve valve with two sets of ports, operating means actuated by the treadle or by the timing drum, and catch mechanism for retaining them in operated position. The timing drum is driven by the piston 508 through a oneway clutch, at a speed which can be adjusted by a second piston 588 and a leak valve 594. The drum carries a series of fingers 504 which operate on the various valves at the appropriate times. Manual means are provided whereby the hydraulic gear and the parts they control may be returned to starting position, e.g. for representing the shoe, either at the end of the shoe clamping operation, or during the automatic cycle.