INJECTION MOLDING NOZZLE HAVING NOSE PORTION WITH HEATING ELEMENT ENCIRCLING THE BORE AND METHOD

摘要

An integral sprue gated injection molding nozzle (10) and method having a melt bore (38) extending centrally therethrough wherein a circular forward end portion (100) of the electrical heating element (68) encircles the melt bore (38) in the nose portion (24) to provide additional heat adjacent the gate (42). The method includes locating the circular portion (100) of the heating element (68) in a circumferential space (172) between a hub member (146) and a funnel member (120) and integrally brazing them together in a vacuum furnace to form the nose portion (24) of the nozzle. The nose portion (24) is drilled and machined to provide the desired gate (42) and configuration depending upon the particular application.