GB1383424A - Sand mould formation - Google Patents

Abstract

1383424 Foundry moulding machine S LARKIN 3 Aug 1972 36366/72 Heading B3F A foundry moulding machine for forming two parallel rows of "flaskless" sand moulds has a moving bed 20 upon which are mounted four hinged walls 40, 41, 42, 43 forming two moulding chambers. At a moulding station 39 a toggle mechanism lowers a cover plate 50 upon the walls 40, 41 to clamp them in grooves 78. A pair of patterns 86 (Fig. 5) are introduced into opposite ends of the so-formed moulding chamber 40, 41,50 and the chamber is filled with sand through a hole 51. The patterns 86 are moved towards one another to compress a sand mould formed in the chamber 40, 41, 50 and, after withdrawal of the patterns 86 and cover-plate 50, the walls 40, 41 are moved away from the sand mould by springs 47, 48. The bed 20 slides rightwards to present the formed mould to an extracting device 96 at one side of the moulding station 39. While the mould is extracted from walls 40, 41 a further mould is formed in the walls 42, 43, which have been moved into the moulding station 39. The bed 20 then moves leftwards to present the second mould in walls 42, 43 to a second extracting device 96 on the other side of the moulding station 39 and the walls 40, 41 return to the moulding station 39 for the production of another mould. In this way, by reciprocating the bed 20, two lines of moulds are built up opposite the extracting devices 96. The extracting device (Fig. 9) comprises a box 102, of approximately the same cross-section of the moulds formed. A rubber ring 106 extends around its periphery and is brought into contact with a mould in a moulding chamber by a ram 98. Pressure air is then admitted to the box 102 through a port 110 during forward ejection movement of the box 102 to distribute pressure equally over the mould surface and avoid deformation. A pattern shuttle (not shown) is provided which lifts and lowers pairs of patterns into and out of the moulding station 39.