Patent GB-930840-A (GB)
Title: Improvements in or relating to the manufacture of shoes
IPC: B29D35/00
Filed: 1959-07-31
Abstract: 930,840. Injection moulding footwear. BRITISH UNITED SHOE MACHINERY CO. Ltd. July 31, 1959 [Aug. 5, 1958], No. 26287/59. Class 87(2). An injection moulding machine for moulding soles to footwear uppers has an injection mechanism, a plurality of mould assemblies which are carried on a conveyer in and out of an injection station, a locating mechanism at the injection station to locate the mould opposite the injection head and a fluid pressure operated device to move the mould into engagement with the injection head. The conveyer, Fig. 1, has two chains 22, 24 which are mounted on sprockets 26, 36 driven by a hydraulic motor and which carry eight plates 34 on which the moulds are mounted, moving each mould into and out of a loading and unloading station, an injection station, six idle stations and back to the loading station. Each plate 34 is supported by rollers 188 running on a rail 184, Fig. 1, and is guided by a roller (not shown) running in a groove 210, Fig. 9, in the rail 184. The lower end of each plate 34 is guided by rollers 202 running between rails 196, 198. The mould, Fig. 6, has side members 60, 62 which are moved inwards towards the base mould 64 by handles 88, 90 connected to the side members by toggles 94, 96 and 98, 102. The foot forms 108 is mounted on a plate 114, adjustably mounted on arms 132 which are pivoted by a spindle 146 to an arm 144 on the plate 34. The foot form 108 is held in operative position by a hook 150 engaging a spindle 148 which is connected to the spindle 146 by links 176, 178. Both spindles 146, 148 have eccentric portions so that on rotating them by the handle 174 the foot form 108 is moved in a direction perpendicular to the plane of the mould to clamp the foot form 108 against the mould. The plate 34 and base mould 64 have a hole containing a bush 218 which engages the injection nozzle 214, Fig. 9. The mould is positioned directly opposite the nozzle 214 by levers 226 which are moved towards each other by a cylinder 240 and piston rod 238 to engage the lower rollers 202. The mould is then swung towards the nozzle 214 by a boss 264 on a piston rod 260, Fig. 6, movement of the mould being permitted by a recess 212 in the guide groove 210, Fig. 9. A tape 288 of plastic material enters a screw feeder 306, Fig. 7, where it is heated and then passes into a heated injection cylinder 290 which has a piston 292 driven by a hydraulic ram 320. The injection nozzle has a valve 268, injection being terminated when a pressure sensitive switch in the base mould 64 is actuated, this also causing the cylinder 290 to be recharged with plastic material. The machine has a control circuit arranged so that it will run for one cycle, i.e. after loading the machine is started by the operator, the mould moves to the injection station, is located opposite the nozzle, then moved into engagement with the nozzle, the plastic material is injected, the injection cylinder is recharged and the machine stops. The control circuit has a selector switch which allows each operation to be initiated manually. The circuit will also prevent operation of the machine until the temperature of the plastic material is satisfactory.