Abstract: In accordance with the present invention there is provided a new and improved internal core lifter for molding and ejecting plastic parts having undercuts. The preferred internal core lifter has a core blade with a first end configured to cooperate with the surfaces of the mold for molding a plastic part and for assisting in safe ejection of the plastic part. The core blade may be pivotally mounted at an opposite end for being disposed at a predetermined molding angle in a range of angles for accommodating various molding angles of mold apparatus. In ejecting the plastic part, the first end of the core blade moves horizontally away from the undercut while moving vertical to assist in safe ejection of the plastic part.

Abstract: An internal core lifter in a mold is provided with both linear motion and pivotal seating in a universal coupling that slides linearly along an ejector plate. The pivotal seating allows the core blade to be used at various angles in different molds, thereby reducing the inventory of core blade needed. To resist high forces encountered during ejection and during the opening and closing of the mold, the preferred pivotal seating comprises wide arcuate dovetail surfaces on the lower end of the core blade and on a slidable support which has linear dovetail surfaces with the ejector plate. The upper end of the core blade may be configured to be part of the molding surfaces to mold an undercut in a plastic part. The upper end of the core blade is moved laterally from the undercut and then is shifted upwardly to engage and eject the part.