Patent GB-732060-A (GB)
Title: Improvements in or relating to shoe upper conforming machines
IPC: A43D21/12
Filed: 1952-07-30
Abstract: 732,060. Grippers for lasting machines. BRITISH UNITED SHOE MACHINERY CO., Ltd. (United Shoe Machinery Corporation). July 29, 1953 [July 30, 1952], No. 19216/52. Class 17(1). A shoe upper conforming machine includes a gripper arrangement for pulling an upper over a last which comprises a carrier 60 with a pair of jaws 66, 68, jaw closing means 72 movable relatively to the carrier, an actuating member 58 connectable with the means 72 for moving the latter relatively to the carrier to close the jaws and for then moving the carrier to tension the upper and an anti-friction device positioned between the means 72 and the carrier to facilitate the jaw closing movement of the means 72. A spring 98 applies force in opposite directions respectively to the actuating member and the carrier to hold the carrier against movement during the closing of the jaws, means are provided for disconnecting the actuating member from the means 72 affer tensioning to cause the jaws to release the upper, and a device restrains the carrier from movement by the spring relatively to the actuating member in a direction towards the shoe when the jaws release the upper. The gripper arrangement is fundamentally like those in Specification 12304/03, [Class 17]. The toe gripper 2, pivoted at 6 to an updraw lever 8 which is rocked by the grooved cam 26 through roll 24 and slide 16 to pull the upper, is withdrawn after pulling by updraw and overdraw springs 18, 32. Jaw 66 is fixed to the carrier 60, and jaw 68, pivoted at 70, is initially held in open position by the finger 80 pivoted on the slide, and moved to the closed position by roll 74 on movement of the slide. Slide 72 is held in the position shown in Fig. 3 by springs 82 (not shown). When bar 58 is moved by lever 8, spring 98 at first holds the carrier 60 stationary and slide 72 is moved by a latch 86 pivoted at 84 on bar 58 and engaged with an abutment 88 on the slide by a spring-pressed plunger 92. When the resistance of the upper prevents further expansion of spring 98 bar 58 moves the carrier 60 with it to pull the upper. When the rocker arm 30 moves inwardly after the upper pulling, it causes finger 80 to pivot and disengage latch 86 from abutment 88, whereupon spring 82 (not shown) moves slide 72 towards the jaws relatively to the carrier, allowing the jaws to release the upper. Spring 18 then moves the grippers further from the shoe. To prevent movement of the carrier, relatively to bar 58, towards the shoe when latch 86 is disconnected a pawl 100 is pivoted with latch 86 and arranged to be swung from an inoperative position into engagement with teeth 102 on the carrier, to 'lock bar 58 to the carrier. To prevent friction between slide 72 and the carrier, when the tail 76 of jaw 68 is engaged by roll 74 to close the jaws, with possible prevention of movement of the carrier, a plate 110 with rolls 114 is arranged between the slide and the carrier in a recess 108 in the latter. The plate is confined between jaw 66 and lug 120 on slide 72, and has a clearance aperture 118 for the tail 76. Two double side grippers 4, similarly operated by updraw lever 40, slide 46, cam 56, and spring 48, each comprise a gripper bar 122 and two carriers 124 each with a fixed jaw 134 and pivoted jaw 138 moved by roll 142 on slide 140. The slides 140 are moved through block 152 and slide 154 by the gripper bar, a lever 148 pivoted at 150 on block 152 and swivelled at its ends in blocks 146 mounted in guides in slides 140 permits relative movement of the slides 140 as may be necessitated by the different thicknesses of the upper engaged by the different pairs of jaws. As shown, the arms of lever 148 are of different lengths. Slide 154 is moved by a latch 160 pivoted at 158 to the bar 122 and engaged with block 152 by spring 162 (not shown). As the side rocker arms move inwards they engage and pivot fingers 168, and lugs 170 on the latter disengage the latch 160 from block 152, disconnecting bar 122 from the slides 140. Slides 140 and 154 are then moved towards the jaws by spring 172. When latch 160 is disengaged spring-pressed pawls 180, also mounted on pin 158, are swung to engage teeth 182 on the carriers 124 to lock bar 122 to the carriers 124. Anti-friction devices 196, 198, similar to 110,114, are arranged between slides 140 and carriers 124. Specification 396,086 also is referred to.