Abstract: An injection molding nozzle for disposition in a mold. The nozzle is for injecting melt into a cavity of the mold, and includes a body having a through bore extending therethrough for receiving the melt. Attached to the body of the nozzle is a nozzle piece secured to the body that defines an outlet communicating between the body through bore and the cavity gate. A nozzle member surrounds the body at a position upstream of the nozzle piece and has an inner surface contacting the body, and an outer surface contacting the mold. The outer surface forms a seal against melt flow upstream from the nozzle member.

Abstract: An injection molding nozzle for disposition in a mold. The nozzle is for injecting melt into a cavity of the mold, and includes a body having a through bore extending therethrough for receiving the melt. Attached to the body of the nozzle is a nozzle piece secured to the body that defines an outlet communicating between the body through bore and the cavity gate. A nozzle member surrounds the body at a position upstream of the nozzle piece and has an inner surface contacting the body, and an outer surface contacting the mold. The outer surface forms a seal against melt flow upstream from the nozzle member.

Abstract: An injection molding nozzle is provided that includes a heater disposed about an insert seated in the nozzle body. The heater provides extra heat about the insert where heat loss to the mold can cause a reduction in melt temperature. The heater remains on from one injection cycle to the next injection cycle. In one embodiment, a thermocouple is used to measure the temperature about the insert so that the intensity of the heater can be adjusted accordingly. The heater can also be used with nozzles used in multiple nozzle applications to balance the flow of the nozzles.

Abstract: An injection molding apparatus and a bushing for use therein. Pressurized molten material flows intermittently from a source through runner channels in a heated manifold and internal lumens in heated bushings for injection through gates into article formation cavities of a mold. Each bushing includes a conically shaped, distalmost section extending substantially centrally into a mold gate. Each bushing also includes a distally opening annular cavity located between its distalmost section and its inner lumen. The annular cavity has outer walls which are substantially parallel to the bushing axis, and inner walls. The inner walls form a distally tapered shoulder having an outer edge and an inner edge. The outer edge extends substantially helically and distally along an axial projection of the proximal portion of the bushing. The inner edge extends substantially helically and distally along an axial projection of the smaller maximum diameter of the conically shaped portion.