The Procter & Gamble Company
Apparatus for molding hollow workpieces

Abstract:

An apparatus and process for molding workpieces usable for consumer products. The workpieces may be injection molded with a cavity formed by a core pin and have an undercut, such as internal threads, in the cavity. The apparatus has a drive system with a stripper plate mounted for alternatingly forward and retracting axial movement. The stripper plate is axially driven and drives a stripper sleeve barrel cam and a core pin base barrel cam, each having respective cam followers. The respective motions of the cam followers are superimposed on a stripper sleeve insert, which drives a core pin sleeve. The core pin sleeve is subjected to responsive three dimensional motion, allowing an internally threaded workpiece to be unscrewed from the core pin sleeve. The system does not require separate drives for the core pin sleeve, a single stripper plate drive being sufficient.