Apparatus for blow molding

摘要

An apparatus for blow molding a thermoplastic container having a concave bottom. A plurality of concentric, nested tubes surround a central rod, the tubes and rod have cooperating end faces which define the bottom of a blow mold. The tubes are interconnected through an actuating key fixed to the central rod and projecting through slots in the tubes. Actuation of the rod actuates the tubes in sequence as the key bottoms in the slots. A second, stop key is fixed relative to the rod and all of the tubes to position the rod and tube end faces in either a concave or convex configuration to defining two consecutive desired bottom shapes for the blow mold.