GB1166710A - Method and apparatus for the Transfer and Injection Molding of Synthetic Thermosetting and Thermoplastic Resins - Google Patents

Abstract

1,166,710. Injection moulding. HULL CORP., and W. T. LA ROSE & ASSOCIATES Inc. 18 Dec., 1967, No. 57476/67. Heading B5A. In the transfer and injection moulding of thermosetting or thermoplastic resin, which may contain glass fibre reinforcement, provided initially in the form of preforms P, the latter pass down a shoot 10 and are fed singly on to rods 18 by the controlled operation of a pair of stop-rods 12<SP>1</SP>, 14<SP>1</SP> operated by pneumatic cylinders. The preform is then pushed up a guide 22 to a pair of rollers 32 on arms 34, 36 by the piston-rod 20<SP>1</SP> of an air cylinder 20, whereby the preform is rotated and heated uniformly by an electronic heater 26. When the preform reaches the desired moulding temperature, i.e. the curing temperature in the case of thermosetting materials, and, in the case of thermoplastic materials, the maximum softening temperature enabling it to be transferred to the mould, the arms 34, 36 are separated and the preform falls to a guide 46 from which it is delivered by a ram 48 to the transfer pot 50 of a closed mould. The latter includes a fixed section 56, with the transfer pot, connected to a stationary heated platen 54, and a movable section connected to a heated platen 58 and urged to mould closed position by an hydraulic cylinder 64. In a modification, instead of the rotatable roller assembly 32, 34, 36, the preform is received in the guide 46 directly from the guide 22 and is rotated by rollers projecting through the guide 46, heated therein, and delivered by the ram to the mould.