GB1352562A - Foundry sand article forming machine and method - Google Patents

Abstract

1352562 Foundry moulding processes and apparatus SHERWIN-WILLIAMS CO 21 April 1971 10576/71 Heading B3F A method of producing a foundry moulding comprises supplying resin/sand mixture to a mould- or core-box and passing compressed air through the moulding formed in the mould- or core-box, the compressed air being injected with a measured quantity of liquid resin-hardening catalyst. In a core-making machine, sand in a hopper 18 is mixed with resin in mixers 15, the mixture passing by way of a hopper 12 and a cut-off valve 11 to a blowhead 8, 9, from which it is blown via tubes 10 into a two-part core-box 21, 22, Fig. 5, supported on a bellows clamping table 6, 7 to form a core. After core-blowing the table 6 is lowered and a gassing-head 42 swung above the core-box 21, 22 and below the blowhead 8, 9. Clamping pawls 28, 29 (which held the core-box parts 21, 22 together during coreblowing) are operated to hold the gassing-head to the core-box part 21. A blast of compressed air is supplied to a manifold 52 and passes through the moulding in the core-box 21, 22, carrying with it a measured quantity of vaporized hardening catalyst, e.g. triethylamine which has previously been injected into the compressed air in liquid form by a single-stroke pump (108). The gassing takes 8 to 12 seconds, catalyst being carried by the air, only for 6 to 10 seconds, the last two seconds of gassing acting to pure the moulding. The spent gases leave through vents 85 and pipe 86 to be vented to atmosphere after passing through a scrubber (106). The table 6 is once again lowered thereby ejecting the moulding from the core-box 21, 22 by means of ejector pins on a spring-loaded ejector plate 80.