Patent GB-553881-A (GB)
Title: Improvements in or relating to shoe upper conforming machines
IPC: A43D13/00
Filed: 1941-12-06
Abstract: 553,881. Coating surfaces. BRITISH UNITED SHOE MACHINERY CO., Ltd, (United Shoe Machinery Corporation). Dec. 6, 1941, No. 15750. [Class 95] [Also in Group VII] A machine for lasting the toe end portion of a shoe has pulling-over grippers, power operated wipers for wiping marginal portions of the upper inwardly over the toe portion of a last, means to trim away marginal material from an inner layer or layers around the toe portion of the upper, and means to apply cement to aid in securing the upper in wiped condition. The mechanism is fluid operated. The trimming and cementing devices are mounted on a carrier swung laterally to bring each device in turn into operative position and lowered from normal raised position into operative position. The trimming devices comprise a knife for the toe end and a knife for each side of the toe. The trimming is dropped into a bin. A yielding toe-band is provided which may be used for up-wiping prior to the advance of the wipers. Thermoplastic adhesive is ejected by a reciprocating pump on to the toe end margin of the insole, the applying means acting as a retarder to the upper while this is over-wiped, so that the upper is dragged over the cement-exuding orifices. The machine is controlled by a treadle, the first depression of which causes the grippers to close and the second depression starts the power cycle of the machine. If the upper has to be repositioned the grippers may be opened by a foot lever which returns the mechanism to starting position. The shoe is positioned 'in the machine by a plate 18, Fig. 42, carrying three pins engaging holes in the last and interchangeably secured to an arm 14 adjustable vertically. The shoe is clamped against the plate by a toe rest 48 and instep support 50, the first carried by a piston 60, Fig. 21. in a cylinder 56, and the second carried by a rod 74 serving as a piston of much smaller diameter than the first, both pistons being supplied with fluid by a pipe 66 controlled by a valve adapted to trap the fluid and thus maintain the toe rest and instep support substantially positively in their operative positions. A toe end gripper 88, Fig. 12, and two side grippers 90 are mounted on a support 92 pivoted on studs 94 for swinging movement heightwise of the shoe, the support normally resting on a vertically adjustable lug 96. The movable jaw of each pair of grippers is operated by a piston in a cylinder 144 or 176. Each of the three grippers is mounted to slide towards and away from the shoe, levers 190 for the toe grippers and 244 for those at the sides being actuated by levers operated by fluid cylinders 222, 296, yield being provided by springs 212, 258. Movement heightwise of the shoe may be imparted to the grippers by fluid cylinders swing- ing the support 92 upwardly about its pivots 94. The upper may be wiped upwardly by a toe former 320, Fig. 21, carried with the wipers 322 on a toe head 324 mounted for up and down movement on two pairs of parallel links 328. The head is moved upwardly for the up-wiping by a pair of fluid actuated cylinders and pistons. The wiper carrier 346 is slid lengthwise of the shoe by a piston rod 348 and cylinder. For quick exchangeability the wipers are held in place by latches. Each wiper has a plurality of curved fingers which interlock to prevent any V-shaped opening between the wipers when in closed position. To close the wipers as they are advanced by the piston each wiper holder carries a gear sector 392, Fig. 25, engaging a gear sector 394 on a lever engaging trunnion blocks 400 mounted to turn on studs on a block threaded on a shaft 406. The wipers may be adjusted for size of shoe by a hand-wheel connected to these two shafts 406 by universal joints and bevel gearing. The toe former 320 comprises a flexible leather band backed by a thin resilient metal'band 448, Fig. 21, and is flared downwardly. The ends of the former are urged forwardly and inwardly by springs so that it can yield during the upwipe. The former can be latched rearwardly when upwiping is not desired, the latch being released at the end of the upward movement of the toehead so that the former may act as a clamping band. The toe former is retracted when desired by a lever 484 co-operating with a latch 544 provided with a torsion spring 556 for urging the latch rearwardly and a spring 558 which urges the latch forwardly when an arm 560 is moved forwardly. When the latch has been thus brought under the lever 484 on the descent of the toehead, the former will be held retracted until a rear arm 554 of the latch contacts with the arm 560 at the end of the upward movement of the toe head, to free this and allow the upper to be clamped against the last in the position in which the grippers have pulled it. A spring 614 threaded over a rod 610 screwed into the toehead if adjustable by a threaded collar 612 to provide downward pressure to the wipers when they have completed their advancing movement over the edge of the insole. The heel rest comprises a pair of blocks 620, Fig. 34, covered by a strip of leather to engage the heel end of the shoe, the blocks being pivoted but separated by V-pins to limit their swing, and carried on a lever 640 pivoted at 642 and actuated by a piston 654 in a fluid cylinder. The upper trimming device 670, Fig. 3, and the cement-applying device 672 are supported on a carrier 674 clamped on a vertical hollow post 676 guided for vertical and for turning movements in a cylinder 678, Fig. 6, carried by the frame, the downward movements being to operative position and the turning movements into position over the toe end part of the shoe, bumpers 684, 688, Fig. 3, determining the limits of swing. Both movements are effected by fluid pressure, the downward movements against the urge of a spring 724, Fig. 6. The upper-trimming device comprises a middle knife 756 for the toe end and two side knives 758 movable in paths curved about a vertical axis opposite the end of the toe. The knives move in a plane parallel to the top faces of the wipers, with their cutting edges spaced from those faces a distance equal to the thickness of the outer layer of the upper materials, the lining and box toe being cut away. The side knives are actuated first, the knife holders being moved along guide-ways 762, Fig. 3, by links pivoted to levers 772 provided with rolls actuated by cam surfaces on a slide 780, Fig. 6, reciprocated by a lever 802 actuated by a fluid pressure piston 794. The middle knife 756 is carried by a curved arm 824 urged upwardly by a spring and depressed by a roll 836 carried by a lever 832 actuated by a roll 842 on the lever 802. During trimming the toe end of the insole is depressed by a holdown 860. The waste material severed is held by a resilient plate 870. As the carrier 674, Fig. 3, is swung to position the cementing device over the shoe the toe end knife is swung over a receptacle 874. As the trimming means is moved downwardly to cause the cementing means to approach the shoe, a push rod 900, Fig. 6, actuates a plunger 894 to move the plate 870 from the knife. Also a cleaver swings between the plate and knife and removes the waste if it has not previously dropped. Thermoplastic cement is maintained liquid in a chamber 924, Fig. 9, and is pumped by a plunger 978 actuated by a lever abutting a fixed stop on the descent of the device towards the shoe. Rise of the plunger, produced by a spring, draws cement by a valve 980, and descent of the plunger forces cement by a valve 984 to a chamber 964, whence diverging pipes with perforations 966, Fig. 11, on their lower sides deliver to the toe end of the insole. The cementapplying device acts as a retarder on the margin of the upper as the wipers advance, and is levelled at 1034 so that it is raised by the wipers. An additional retarder 1036 is provided with teeth 1039. When the machine is in use a pump driven by an electric motor draws fluid from a reservoir 1076, Fig. 29, and delivers it to a pressure chamber 1070 communicating with valves controlling the various fluid cylinders. Normally, the fluid returns freely to the reservoir through a sleeve valve 1088 slidable on a tube having a partition 1098 and parts 1100, 1102 on either side of the partition. The valve is controlled by an arm 1106 pivoted at 1108, urged in a direction to open the valve by a spring 1116 and in a direction to close it by a spring 1126 actuated by a lever 1118 the rear part of which can yield against a spring 1122. A latch 1132 prevents return movement of the valve until released by an arm 1138 actuated by a pin on an arm fixed to a control shaft 1220. The lever 1118 is actuated by a rod 1150 connected to an arm 1152 fast on a rock-shaft 1154 carrying an arm 1160 supporting a latch 1162 connected to a treadle lever 1172. The same depression of the treadle which establishes pressure in the chamber 1070 also causes the jaws of the grippers 88 and 90 to close on the upper by similar valve mechanism actuated by upward movement of a rod 1200 actuated by a block on an arm of the rock-shaft 1154. A screw 1212 frees the rod at the end of its upward movement. If the upper materials are not properly positioned the operator may release the upper for repositioning by engaging with his foot a pad at the end of a rod 1214, swinging the arm 1160 and depressing the rear half of the lever 1118, a face thereon freeing the latch 1132 to terminate the pressure in the chamber 1070 causing the gripper jaws to open. A depression of the treadle causes the jaws to close on the upper. The machine is started by a succeeding depression of the treadle, the shaft 1220 being driven in one direction by a pinion gearing with a rack 1230 integral with a piston 1226 returned by a spring. A brake is provided on the shaft 1220 to prevent reverse movement. The valve supplying the cylinder housing the piston 1226 is similar to those previously described and is similarly controlled by an ar