Patent GB-767529-A (GB)
Title: Improvements in or relating to shoe upper shaping machines
IPC: A43D21/18
Filed: 1954-05-27
Abstract: 767,529. Pulling over machines. BRITISH UNITED SHOE MACHINERY CO., Ltd. (United Shoe Machinery Corporation). May 26, 1955 [May 27, 1954], No. 15626/54. Class 17 (1). A pulling over machine having work supporting means, a toe gripper, at least one pair of side grippers, and means to secure the forepart of the upper, in pulled over relation, at least temporarily, to the shoe bottom member, has a plurality of springs associated one with each gripper to exert a pulling force, and a common support for the ends of the springs. The position of the support is changed by manually operated means to vary the intensities of the pulling forces applied to the grippers. The arrangement is such that the intensities of the pulling forces remains substantially constant throughout the movement of the grippers. The tension applied to the upper by the side grippers may be increased or decreased, during the dwell period, by manual operation of means which are normally disconnected but may be connected at will. The machine has a toe gripper 100, side grippers 102, toe tacker 104, side tackers 106, shoe rest 108, side clamps 110 (not shown), heel rest 112, tack separating and supplying mechanism 120, and operating treadles 122. (not shown), 124 (not shown). Rolls 192, 206, 206. (Fig. 3) on arms 190, 204, 204, of pivoted gripper operating levers 130, 132, 132, engage pads 194, 208, 208, on slides 196, 210 moved vertically under control of cams 202, 216, and when the slides move downwardly springs 156, 172, 172, acting through 138, 160, 160, and 136, 162, 162, swing levers 130, 132, 132 to cause the grippers to close upon and then pull the upper. The intensity of this tensioning is controlled by movement of a lever 178, normally locked by a pawl 180 which may be withdrawn by means of a plunger 186, which through 176, 174 turns shaft 150 and integral arms 148, 168, 168 fast thereon, the latter moving rods 146, 166, 166, relative to sleeves. 144, 164, 164 and so adjusting the tension of springs 156, 172, 172. Arm 148 is shorter than arms 168 so that variation of the pull of gripper 100 is less than that of grippers 102. Bell cranks 138, 160, 160 are so angularly disposed that their mechanical advantages increase as the tensions of springs 156, 172, 172 decrease, so that the grippers apply a constant pull throughout their movement. The mainshaft 218 stops to provide a dwell period during which the springs act directly on the grippers, and during this period the pull of the grippers may be adjusted by movement of handles 302, 322, 322 which adjust the position of levers 130, 132, 132. Hand grip 308 is connected through 310, 314, 312, 316 to mechanism for opening the jaws. To facilitate movement of the grippers lengthwise of the shoe the side grippers may be moved simultaneously to relieve the pull on the upper by movement of a hand lever 342 which through other parts not shown and 362, 364, 366, 368, and 374 swings arms 376, 376, integral with bell cranks 160, 160, counterclockwise (Fig. 3). The action of the side grippers is damped by a dash-pot 380 acting through 381, 382, 360. In the collapsing movement of the grippers cam 387 causes the valve of the dash pot to open so that the side grippers move quickly away from the bottom of the shoe. In addition to the control by dash pot the pull of the side grippers may be controlled by operation of lever 342. Grippers 102 are moved lengthwise of the shoe, to enable the upper to be positioned relatively to the last, by means of handles 400 (not shown), 402 (not shown) which through 410, 412 move guide members 408, 414. The grippers are held in these positions by engagement of members 426, 420, when the tackers, in their outermost positions, engage the camming surface 442, but when the tackers later move inwardly springs 416 return the grippers to their normal positions. A toe cap gauge, normally in an idle position in which it may be latched, falls into operative position when handles 322 are moved upwardly on operation of the side grippers. Grippers 100, 102, 102 are positioned initially by spreader mechanism including a bar 500 with roller 502 engaging gripper 100 and wedge block 504 controlling the gripper positioning arms 506. The position of the wedge with bar 500 is adjusted, to vary the spread, by means of a handle 538 which is moved inwardly to engage gears and then swung so that through the gears, the adjusting screw 511 is rotated, and bar 500 is adjusted relatively to wedge 504 the lengthwise position of the toe gripper may be changed without changing the spread of the side grippers by means of a handle which operates similarly to handle 538. The grippers are moved inwardly, by springs, out of the way of the overlaying and fastener inserting devices when rack 584 moves downwardly. The overlaying etc. devices are moved by mechanisms including a support 600 rocked on shaft 602 by a cam 612 acting through arm 606, and the slidable rock bar 584 movable lengthwise by cam 682 acting through 674, 672, 670, and gear 616 which meshes with teeth 614 on the bar. When the rock bar is moved downwardly shortly after the dwell period it moves housings 628, via 618, 620, 624, 626, and housing 650, and hence via plungers 630 and slides 658 moves side tackers 106 and toe tacker 104 inwardly over the bottom of the shoe until these movements are arrested by engagement with side clamps 110 (not shown) and the shoe respectively. On continued movement of bar 584, and hence of housings 628, 650, plungers 640, 652 are wedged outwardly and latch plates 644, 662 withdrawn, so that the driver bars 646, 664 are released to the actions of their springs. Later support 600 is rocked clockwise and then counterclockwise by cam 612, and just before the latter movement bar 584 is moved upwardly to return the tackers and re-engage latches 644, 662 with bars 646, 664, so that on subsequent rocking of support 600 the driver bar operating springs are recocked. Side clamps 110 are moved yieldingly into engagement with the upper at opposite sides just before the grippers are opened, and are later withdrawn under control of a cam 712. The shoe rest 108 is mounted on a platform 760 which is swung about shaft 762 by cam 772, to a limit determined by screw 775. The heel rest 112 is adjustable on a slide 780 movable on member 790 which is pivoted about 792 and swung first to one side and then to the other as a cam roll 828 moves first along one of the cam tracks 830, 832 and then along the other, the linkage from the roll being adjustable so that the extent of swinging may be regulated, and the entrance to the cam tracks being controlled by gate members. A handle 866 may be used, when the machine is stopped, to swing the heel rest to its other position, this movement transferring the roll 828 to the other track. Slide 780 is connected to a piston 894 and is normally retracted against stop 897, as in Fig. 14, by a spring 898 when pressure fluid is introduced through 930 piston 894 moves upwardly and engages the rest with the heel, as the pressure then builds up a shut off valve is actuated and the fluid moves piston 906 which engages pawl 902 with ratchet 900 to lock the rest. Conduit 930 is connected to a pressure source or to exhaust by a cam-actuated slide valve. When treadle 122 is depressed it acts via 1064, 1062, 1044, 1046 to raise link 1048 so that latch plates 1050, 1040 are disengaged, and springs 1020 urge the clutch and brake disc 1014 into engagement with the friction drive surface 1016 of the motor driven pulley 1008, so that through 1004, 1002, and 1000 the main shaft 218 is rotated. Cam 1060 then moves link 1048 to the right, Fig. 23, 1050 moving beyond 1040, and then to the left to restore the parts to the Fig. 23 position, when, with latches 1050, 1040 locking arm 1038, the thrust collar 1022 and rods 1024 press disc 1014 against the friction brake surface 1018, and the mainshaft 218 is brought to rest on a succeeding depression of the treadle the action is repeated. Shaft 218 rotates 155 degrees before and 205 degrees after the dwell. During the dwell, after the initial operation, the grippers may be returned to their original position by actuation of treadle 124, which operates a motor reversing switch, depression of the treadle at all other times being prevented by a cam actuated locking member. As an additional safety measure, at these times, the reversing switch is de-energised. The tack supplying and separating mechanism 120 includes a tack pot 1150 rotated from pulley 1008, a cam-reciprocated separator 1162 which moves to the left, at the beginning of the second stage, to pick up a load of tacks, and to the right, just before completion.of the cycle to discharge the previously separated load of tacks through passages 1182 into tack tubes 1184, and a slidable gate member 1188 which has passages 1190 aligned with passages 1182 in the idle position of the machine, Fig. 28, and angular passages 1192, and which is reciprocated in time relation with and in the opposite direction to separator 1162. When separator 1162 moves to the left it actuates valve 1202 and air under pressure passes through 1200, 1194, 1196, 1192, since gate 1188 has moved to the right, and 1182 to tubes 1184, and tacks are blown therefrom into the driver passages of the tackers. During the operation of the main shaft lubricating oil is continuously delivered by a pump to pipe 1250 to drip from apertures 1252 on to the moving parts. Means are provided for turning over the machine by hand. Specifications 12304/03, [Class 17], and 381,208, are referred to.