Patent GB-859671-A (GB)
Title: Improvements in or relating to machines suitable for use in the manufacture of shoes
IPC: B29C35/00
Filed: 1956-06-29
Abstract: 859,671. Shoe sole moulding machines. BRITISH UNITED SHOE MACHINERY CO. Ltd., and BARTON, G. C. June 28, 1957 [June, 29 1956], No. 20140/56. Class 87(2). A carrier for a foot on which a shoe to have a sole moulded thereon is supported is raised by power-operated means to an inoperative position, relative to moulds which shape the sole to the shoe bottom, on the conclusion of a moulding operation and allowed to descend into operative position for the commencement of the next moulding operation. The moulds include a pair of side moulds, one of which is brought into shoe-engaging position prior to the other thus providing an opportunity for the shoe to align itself to the moulds, and a sole mould which is held in operative position under relatively low pressure for a predetermined period of time to allow the rubber to spread evenly over the mould surface, a timing device automatically bringing about the application of relatively high pressure after the elapse of this period. Side moulds. The machine illustrated has two moulding stations and secured to the forward and rearward faces of the outer side mould carriage 94 at the right hand station are two links 154 which extend widthwise of the machine and their leftward end portions are connected with the forward and rearward faces of the inner side mould carriage 70 at the left hand station. In a similar way the left hand outer mould carriage 96 is connected to the right hand inner mould carriage 72. When oil pressure is exerted below the pistons 138 in cylinder blocks 134, Fig. 4, the lower arms of the bell crank levers 144 swing upwardly under the action of rods 140 and this movement causes the outer side mould carriages 94, 96 to move inwardly and, at the same time, by reason of links 154, 156 the inner side mould carriages 70, 72 move outwardly towards their respective shoes. Owing to the securing screws connecting them to the links passing through slots in the links, the inner side mould carriages do not at this stage move to their fully closed positions. They are moved to these positions by the rising of pistons 38, 42, Fig. 2, which act through links 56 and blocks 63 to cause toggles formed by links 64, 66 Fig. 1, to be made. Sole mould. The sole mould for each station, indicated at A, Fig. 1, rests on a heater block H which in turn rests on a ram head 31 of the double-acting piston 26. When the ram heads 31 are raised, the cross-bars 44, 74 are likewise raised, causing the compression springs 84 to push upwardly on the collars 82 to raise rods 86 and thus the wedges 90, which are pushed between the bridge blocks 14 on the machine frame and wedge-shaped projections 92 on the outer side mould carriages, 94, 96, thus preventing their outward movement under the thrust to be exerted by the sole moulds. Meanwhile pressure is still being built up below piston 138 and when sufficiently high a spring valve in the timing apparatus is actuated which in turn actuates a linkage system (to be described later) and this causes high pressure oil to be brought beneath pistons 26 so that the sole moulds are thrust more firmly upwards and the soles become firmly vulcanised to the shoes. After a further predetermined period of time, oil under high pressure is admitted above the pistons 26 causing them to move downwardly, and thus also to move the sole moulds and wedges 90 downwardly. Oil is simultaneously admitted above the pistons 138 which cause the outer side mould carriages 94, 96 to move outwardly and the inner side mould carriages 70, 72 to move inwardly, the toggle links being broken by the downward movement of the ram heads 31 causing the cross-bars 44 to bear on the lower portions of slotted links-46 which are connected to toggle break links 52. Shoe carriers. For supporting a shoe between each pair of side moulds, the machine is provided with bridge members 102, 104 in each of which are carriers 158 which support the feet 160 on which the shoes are mounted. When the bridge member 102 is in its downward position its outer limb rests on a roller 164 movable widthwise of the machine in a channel in the machine frame to which a rod encircled by a light compression spring 166 is secured. The roller is restrained from being pressed out of its channel by an upwardly extending leaf spring 168. The inner limb 170 rests on a roller 172 mounted in a channel set in centre bridge block 16, a similar roller 174 on the right side of this channel supporting the left hand limb of the right hand bridge member 104. A compression spring 178 mounted on a rod 176 bears against the rollers 172 and 174. The rearward limb 101 is mounted by means of a ball and socket connection on a plate 110 which rests on rollers 108 set to be movable widthwise in a channel of a bar 106. A downwardly extending lug set in the plate 110 has a spring (not shown) which presses against the rollers 108 which are restrained from excessive movement by leaf springs 107. The carrier is thus free to move both laterally with respect to the side moulds and about an axis extending heightwise of a shoe in operative position. When a pair of shoes have had soles vulcanised to them, the side moulds move apart and the bridge members 102, 104, are raised so that the feet are moved to an exposed position for removal of the shoes. This is effected by fluid pressure which is exerted beneath a piston 136 in the cylinder block 134, the link 180 rising and bearing against the underside of the right hand limb of the bridge member 104, raising it clear of the rollers until its upper-most position is reached. The left hand limb is raised by a similar link extending from the right-hand of a pair of pistons 40. The rearward limbs 101, 103 of the two bridge members are supported on the bar 106 connected by link 100 to piston 98 by which means they are raised. The carrier is prevented from being lifted away from its operative position by the upward pressure of the sole mould by pressure-resisting blocks 188, 190, 192 being moved into engagement with the bridge members as a consequence of the advancement of the side moulds into operative position. The carrier 158 is similar to that described in Specification 824,106 and may be moved forwardly and then pivoted upwardly to present the foot to the operator. It differs from the above however, in that itis hydraulically operated by a piston 264 which causes it to be moved in a channel, the flanged blocks 260 mounted on the carrier travelling along slots 262 in the side walls of the bridge portion so that the carrier rides off rolls 270 supporting its rear end. Continued advance of the piston 264 causes the link 286, Fig. 1, the lower end of which is embraced by upstanding lugs 284, to swing upwardly and forwardly about its connection with a lever 296 and the carrier is thus tilted upwardly. Mechanical linkage system. This is constructed to actuate certain valves at different times during the cycle of operations. These valves include a bridge valve 332 for causing upward and downward movement of the bridge members, the downward movement of which is also controlled by two valves 336. The side moulds and toggles are moved into operative positions by the operation of valve 338, Fig. 4. The ram heads have their upward and downward movement regulated by a valve 340 (not shown) immediately behind valve 338. A changeover valve 342 (set rearwardly of valve 340) switches the low pressure flow to pistons 26 to one of high pressure. To commence operation of the machine, starting handle 310, Figs. 1 and 4, is swung leftwardly causing rod 346 to move upwardly, also lever 348, member 352, rod 360, and the valve 332. This movement of the valve causes the pistons 264 to move rearwardly, so that the foot carriers 158, and feet and shoes thereon, are swung to their rearward operative positions, set screws 334 at the forward extremities of the carriers then engaging push members 362 on valves 336 causing oil beneath the pistons supporting the bridge members to be ducted to exhaust and hence the bridge members to descend. This descent of the bridge members is arranged to bring the valves 338 and 340 to their upward position, the former causing oil at high pressure to be brought beneath the pistons 138, to move the side moulds (the outer only to their final position), and beneath the toggle pistons 38, 42, the arrangement being such that the toggles are not straightened until after the side moulds have been moved by the action of the pistons 138. The latter valve brings oil at low pressure to bear against the pistons 26 causing the ram heads 31; also the wedges 90, to rise. After a predetermined period of time (e.g. 2-3 minutes) the timing device actuates the change over valve 342. After a further predetermined period of time (e.g. 8 minutes) the valves 338 and 340 are returned to their lowered positions and the reverse cycle commences. If at any time during the operating of the machine, an operator wishes to stop the cycle of operations, means are provided whereby the valves 332, 338 and 340 are depressed to their downward positions.