Patent GB-470768-A (GB)
Title: Improvements in or relating to methods of and machines for use in the manufacture ofpre-welted boots or shoes
IPC: A43D21/12
Filed: 1936-02-20
Abstract: 470,768. Lasting &c. ; pre - welted shoes. BRITISH UNITED SHOE MACHINERY CO., Ltd. (United Shoe Machinery Corporation) Feb. 20, 1936, No. 5099. [Classes 17 (i) and 17 (ii)] In a method of making pre-welted shoes, a welt is attached to the margin of an upper and the forepart of the upper is subsequently' positioned on a last by movement between last-engaging and welt-engaging means of a machine, the upper being retained on the last by the welt, which is substantially shorter than the periphery of the bottom of the last. A machine for pulling a pre-welted shoe upper on to its last for use in carrying out the above method comprises upstanding upper supporting members 30, 37, Figs. 1 and 8, which engage the exterior of the upper 232 within the crease formed between the welt and the upper, spreader members 40, 42 which engage the interior of the welted margin of the upper, gripping plates 158, 204 which engage the face of the welt to which a sole is to be attached, and a presser plate 118 which presses the last 236 into the upper. The side and toe welt crease-engaging plates 30 and 37 terminate in springy fingers 32 and 43 respectively, and are adjustably mounted on a plate 28 which is arranged to slide forwardly and rearwardly of the machine and is secured in position by means of a thumb screw 38. The toe and side spreader plates 40, 42, which are provided with springy fingers similar to those on the plates 30, 37, are secured to a bracket 44 extending forwardly from a vertical cross-head 46. The cross-head is slidably mounted on parallel vertical shafts 48 extending between a fixed cross-head 50 and a cross-bar 25 at the top of the machine, so that the spreader plates can be raised and lowered. For bending the side spreading plates 42 inwardly to facilitate their entrance into the forepart of the upper and holding them so positioned during their downward movement, a pair of horizontal screws 54 are mounted in arms 56 extending from a slide 58 also mounted on the shafts 48. The screws 54 bear against cam surfaces 60 on the spreader plates, and the plates are bent inwardly to the full extent when the cross-head 46 and the slide 58 are in abutting relationship, a position in which they are normally held by a spring 62. The toe spreader is similarly bent inward by a screw and cam surface (not shown). The movement of the cross-head 46 is limited by stops 90, 92, Fig. 2, and an abutment 88 on the cross-head. The crosshead 46 and the slide 58 are normally held at the limit of their upward movement by means of a spring 68 attached to the machine at 70, Fig. 2, and operating through a bell-crank lever 72 and a link 78 attached to an ear 80 on the slide. The slide and cross-head may be lowered by the operation of a treadle connected to the bell-crank lever 72, by a link 84. When however the cross-head 46 is stopped by the stop 92, the spreaders then being within the upper, the slide can be moved still further down by the treadle, extending the spring 62, moving the screws 54 away from the cam surfaces and thus allowing the spreaders to move apart to engage the inner margin of the upper. As the cross-head and slide are moved apart, a spring 98 pulls a spacer member 94 pivoted on the slide into position beneath a block 96 on the cross-head. This prevents the cross-head and slide from abutting, and thereby maintains the spreaders in their outspread position until they are removed from the shoe and the spacer is released by means of a stop 102 which engages an arm 100 attached to the spacer as the slide is raised. When the spreaders reach the limit of their downward movement, a latch 106 pivoted to the machine head at 107 and operated by a spring 110 prevents them from rising again until the latch is released by a screw 198 secured to the movable presser cross-head 124. As the screw descends during the pressing operation, it engages an arm 200 on the latch and releases it. The presser rod 116 is secured in a vertical bore 121 in a boss 122 projecting downwardly from the front of the presser cross-head, and a presser plate 118 is secured on the end of the rod. The presser can be raised or lowered on the shafts 48 by means of a treadle operating through a link 148, a bell-crank lever 146, toggle links 140, 142, and a link 134. The presser head is normally held at the limit of its upward movement by a spring attached to the treadle. The toe gripper member 158, Fig. 2, is formed as a plate with the under surface of its forward end serrated, and is slidably mounted in a groove in the top of a plate 162 secured to the bottom of the fixed cross-head 50. The gripper 158 is yieldingly held in its retracted position by a spring 166. For moving the toe end gripper 158 forwardly during the first part of the downward movement of the last depresser, a cam plate 174 is secured to the rear portion of the presser cross-head 124. As the cross-head moves downward, the cam engages a cam roll 178 at the end of a lever 180 pivotally mounted in a boss 182. The lower end of lever 180 has adjustably clamped in it a rearwardly and forwardly extending threaded sleeve 184 within which there is slidably mounted a plunger 186 the forward end of which engages the rear end of the toe end gripper 158 and moves the latter forward during the downward movement of the presser cross-head 124. The plunger 186 is backed up by a compression spring 188 coiled about a reduced stem 190 formed integrally with the plunger. The rear portion of the stem 190 extends through the rear portion of the sleeve 184 and has its projecting end threaded for the reception of stop nuts 192. The side grippers 204 are similarly operated. A gauge plate 238 is secured to a cross-bar at the front of a horizontal slide which is secured in the desired position by screws 244. The gauge plate is used for centering the heel portion of the upper which is supported by hand. The upper is first placed on the welt crease engaging plates 30 and 37 and the spreading plates lowered by the appropriate treadle so as to engage the inner margin of the upper. The presser head is then depressed, the gripper members being brought forward by the operation of the cams so as to engage the welt. The cams are so designed that further depression of the presser takes place without movement of the grippers, after which the toe gripper acts slightly in advance of the side grippers to push the welt over the edge of the last, the spreaders having previously been withdrawn.