Alignment assemblies for plastic injection molds

Claim 1

In a die for molding plastic parts in which there are a plurality of openings therein communicating with cavity means for the reception of plastic and which is adapted to coact with a plurality of nozzles, one for each opening, an alignment assembly in each opening comprising, said opening having a bore portion and a counter bore portion separated by a shoulder, a valve body having a stem portion axially slidably and sealingly disposed in said bore portion and an enlarged head portion disposed in said counter bore portion, said stem of the valve body being configured to coact with the bore to provide tilting movement of the valve body within the bore, said enlarged head portion being disposed to coact with said shoulder to limit the axial travel of said body in the direction toward said cavity means, said body having a through axial opening, said head portion having an outwardly oriented surface thereof shaped complimentary to the external shape of its respective nozzle and disposed to mate therewith, whereby the pressure generated by the plastic in the cavity means at the conclusion of the ejection cycle will move the valve body axially in the bore and force the surface on the head portion thereof into sealing engagement with its respective nozzle.