GB728108A - Improvements in or relating to machines for making shell moulds - Google Patents

Abstract

728,108. Moulding-machines. SUTTER PRODUCTS CO. June 5, 1953 [June 18, 1952], No. 15633/53. Class 38 (1). A machine for automatically making shellmoulds comprises a displaceable oven located in its upper portion and a sand-resin-mix box in its lower portion, a pattern-carrying assembly invertibly disposed intermediate the box and oven, mechanism for intermittently moving the assembly from an upright to an inverted position, mechanism operable in its inverted position for clampingly engaging the assembly over the box, permitting said box to be carried with the assembly to the upright position to dump the mix upon the pattern, means for maintaining the assembly at a predetermined temperature to attract to it a sufficient quantity of the mix to form a shell-mould thereon, and control means for actuating said mechanisms in timed relationship with each other. The mix box 26 is carried on sprung supports 19 on a cradle having a limited vertical movement through a pneumatic cylinder 25. Above the cradle, rotatable stub shafts 31, 31<SP>1</SP> are keyed to, and support, a roll-over pattern-plate assembly comprising a frame 33 with a depending support frame 34. The assembly is rotatable through 180 degrees by a chain 37 connected to piston rods 38, 38<SP>1</SP> and passing over a sprocket wheel 36 keyed to the shaft 31. The assembly supports a pattern plate 44, Fig. 8, beneath which are disposed heater-units 46, a refractory plate 47 and insulation 48. A stripper-plate 51 supports ejector pins 50 normally flush with the upper face of the pattern-plate, the stripper plate being vertically movable by a piston 64. Guide pins 67, 67<SP>1</SP> on the stripper-plate move in guides 65, 65<SP>1</SP>. The frame 33 carries pistons 69 at front and rear which operate clamping- fingers 73, 73<SP>1</SP> which may engage pins 75, 75<SP>1</SP> on the mix box and lock it to the pattern. Above the pattern assembly a curing oven 77, Fig. 4, is movable on tracks 82, 82<SP>1</SP> to an operative or inoperative position under the action of a piston 87 operating on a lever 86<SP>1</SP>, 88. Supported on the roof of the oven is a spray system, for spraying parting liquid on the pattern-plate before investment, comprising four jets 100 each directed to a quarter section of the patternplate. The sprays are vertically movable by a piston rod 96 connected to a pivoted arm 97. The actuating pistons are sequentially operated in timed relationship by a cam-shaft operating hydraulic valves.