Abstract: An injection molding apparatus method and system for molding a plastic article having inward or outward projections on the exterior surface. The injection mold has a first and second mold part adapted to move between a closed, molding position and an open, article-recovering position and which defines a mold cavity for an article to be molded. The first expandable cavity mold part has a base with an opening therethrough and a plurality of outwardly tapered arms extending from the base to an open end that extends into the mold cavity where it is held in place by a striker plate during the injection molding process. The second inner mandrel mold part has a one and other end adapted to move reciprocally and longitudinally within the base and arms of the expandable cavity element, the top end threaded to form the interior threaded surface of the injection molded article.

Abstract: An expandable cavity core element for use in a method and system for molding a plastic article having inward or outward projections on the exterior surface. The injection mold has an expandable cavity core element adapted to move between a closed, molding position and an open, article-recovering position and which defines a mold cavity for an article to be molded. The cavity element has a base with an opening therethrough and a plurality of outwardly tapered arms extending from the base to an open end that extends into the mold cavity where it is held in place by a striker plate during the injection molding process. The cavity element has an outer, tapered exterior surface length which is always equal to or larger than the total molding length of the interior molding cavity. The cavity element may include an outwardly tapered exterior surface or a multiple-tapered exterior surface, such as an outwardly tapered surface and then an inwardly tapered surface.

Abstract: An injection molding apparatus method and system for molding a plastic article having inward or outward projections on the exterior surface. The injection mold has a first and second mold part adapted to move between a closed, molding position and an open, article-recovering position and which defines a mold cavity for an article to be molded. The first expandable cavity mold part has a base with an opening therethrough and a plurality of outwardly tapered arms extending from the base to an open end that extends into the mold cavity where it is held in place by a striker plate during the injection molding process. The second inner mandrel mold part has a one and other end adapted to move reciprocally and longitudinally within the base and arms of the expandable cavity element, the top end threaded to form the interior threaded surface of the injection molded article.

Abstract: A collapsible core and molding apparatus and method for molding a plastic article having an undercut and a non-undercut portion. The collapsible core includes a center core pin and a core sleeve about the core pin and with the core pin having a small plurality of alternating, uniform, narrow, non-collapsing segments secured to the center pin and the same plurality of uniform, alternating, wider, arcuate, collapsing segments secured to the core sleeve, the wide collapsible segments adapted to move between the non-collapsed segments to form the expanded position for a molding operation where the wide segments are separated by the narrower segments, and a collapsed position where the collapsible segments collapse radially inward on the axial withdrawal of the center pin to form a generally cylindrical, cross section, arcuate area and to permit the ejection of a small molded plastic article from the mold.

Abstract: A molding core has side by side segments assembled for rocking about pivots intermediate their ends, and are rocked to their alternate positions by an actuating pin (or pins) having camming surfaces for that purpose, arranged for non-interference of the pin with the rocking movements of the segments.