Abstract: A molding arrangement is provided for multi-level stack molds wherein mold sets and runners are made up of modular sections interchangeable individually or as larger assemblies for exchanging molds for one part for those for different parts or exchanging runners between hot tip and valve gate designs to accommodate different molding arrangements. The arrangement has discrete melt paths for each mold level, at least some of which extend around rather than through the mold levels and which incorporate readily separable connectors. This enables one set of molds and possibly as well the runners for one mold level to be interchanged without interfering with the mold and runner arrangement for an adjacent level.

Abstract: A molding arrangement is provided for multi-level stack molds wherein mold sets and runners are made up of modular sections interchangeable individually or as larger assemblies for exchanging molds for one part for those for different parts or exchanging runners between hot tip and valve gate designs to accommodate different molding arrangements. The arrangement has discrete melt paths for each mold level, at least some of which extend around rather than through the mold levels and which incorporate readily separable connectors. This enables one set of molds and possibly as well the runners for one mold level to be interchanged without interfering with the mold and runner arrangement for an adjacent level.

Abstract: A melt distribution system for a four-level stack mould which avoids the use of a central spruebar extending axially along the moulds. The melt distribution system incorporates leg manifolds for registering with an injection machine nozzle to divert melt radially outwardly from the injection machine nozzle. A first conduit extends from the leg manifold parallel to but axially spaced apart from a mould axis to a central distribution block. Melt is bifurcated in the central distribution block to respective crossover conduits extending from opposite sides of the central distribution block. The crossover conduits are generally parallel to but spaced apart from a mould axis. The crossover conduits fluidly communicate with first and second main manifolds in which melt flow is directed to respective injection nozzles.