Apparatus for the manufacture of patterns or models of synthetic material for precision foundry castings

Claim 1

Apparatus for the manufacture of patterns for blade wheels from synthetic material, said apparatus comprising a rotatable shaft, means for supporting on said shaft an annular rim which Is to serve as the hub of a blade wheel pattern, means for rotating said shaft and said rim thereon, means for positioning said shaft in angular positions corresponding to locations at which blades are to be applied to said rim, the rim having adhesive applied thereto at the locations whereat the blades are to be applied, a mould adjacent said rim and constituted by two parts one movable with respect to the other, said mould having an external shape permitting it to be intimately applied against said rim, said parts of said mould having respective external recesses cooperatively defining a moulding cavity with a profile corresponding to that of a blade when said parts are assembled together, said cavity communicating with the exterior, on the one hand by a first orifice closed by said rim during the moulding operation and on the other hand, by a second orifice through which a moudable material can be introduced into said cavity; means arranged opposite said cavity of said mould at the time of the moulding operation for injecting said moudable material into said cavity via said second orifice and means for controlling the relative movements of said parts of said mould one with respect to the other so as to (a) assemble them together and apply them intimately against said rim before the moulding operation and (b) separate them from each other and from the rim after the moulding operation, each part of said mould having a face applied against the corresponding face of the other part of said mould during the course of the moulding operation, said external recess in each of said parts forming the molding cavity being formed in said face, a second recess being formed in each of said parts at the rear of said parts opposite said face, said means for controlling the relative movement of said parts of said mould being engaged in the rear recesses of said parts of said mould and being articulated on a fixed frame, and means for actuating the means which controls the relative movement of said parts to pivot on said fixed frame.