Injection mold for elongated, hollow articles

摘要

Thermometer probe covers having an extremely thin wall integral tip for enhanced heat transfer are injection molded by unique mold core construction and venting configuration. A tungsten carbide core minimizes core deflection to maintain improved concentricity of core and cavity. Maintainance of concentricity in quantity production apparatus is improved by a combination of relatively loose cantilevered mounting of an end of the core together with a press fit locking of the core upon closing of the mold. Venting of cavity gas during injection of mold material is precisely controlled through symmetrically distributed vent orifices in both the core and the female mold part. Core venting is controlled by a plurality of orifices and a manifold provided by a water cooled core vent pin within a bore of the core.