Injection molding elongated probe having integral heating element and locating means

Claim 1

In an injection molding system having an elongated heated probe and a melt passage which extends to convey pressurized melt from a heated manifold to a gate in a cavity plate leading to a cavity, the heated probe having a generally cylindrical outer surface and a forward tip end, the heated probe being mounted to extend through the manifold and centrally axially into a straight portion of the melt passage which leads to the gate, said melt passage being substantially larger in diameter than the heat probe, the heated probe extending to a position wherein the tip end of the heated probe is adjacent the gate and the melt flows around the probe longitudinally to the gate, the improvement wherein; a locating sleeve having a forward end and a rear end is seated in the cavity plate in coaxial alignment with the straight portion of the melt passage, the sleeve having a central bore extending axially therethrough which is equal in diameter to and forms part of the straight portion of the melt passage with the heated probe extending centrally therethrough, the locating sleeve having a plurality of spaced locating means extending radially inward into the central bore to contact the outer surface of the probe to accurately locate the probe centrally in the straight portion of the melt passage with the tip end of the probe in central alignment with the gate, at least one of the locating means being partially hollow to receive a thermocouple therein to measure the temperature of the melt flowing past the said one locating means.