Injection nozzle with a removable heater device having one or more heating elements

An injection molding apparatus, comprising:

• a manifold having a melt channel;
• a mold cavity plate having a mold gate and a nozzle bore therein;
• at least one nozzle including a nozzle body positioned in the nozzle bore, the nozzle body having an outer surface and a nozzle melt channel in fluid communication with a melt channel in a manifold;
• and
• a releasably securable film heater device releasably secured to the outer surface of the nozzle body, the film heater device including first and second film heating elements that are positioned about the nozzle body to cover substantially the same area of the melt channel;
• wherein the film heater device provides a desired amount of heat from one or both of the first and second film heating elements.

A method of heating a hot runner nozzle, comprising:

• providing an injection molding apparatus including a nozzle having a nozzle body with an outer surface and a melt channel;
• and
• releasably securing a film heater device to the outer surface of the nozzle body, the film heater device including first and second film heating elements that are positioned about the nozzle body to cover substantially the same area of the melt channel;
• and
• controlling one or both of the first and second film heating elements to provide a desired amount of heat.

An injection molding apparatus, comprising:

• an injection molding manifold having a manifold melt channel;
• an injection molding nozzle adjacent said manifold, said nozzle having a nozzle head portion and a nozzle body portion and including a nozzle melt channel, wherein said nozzle body has a substantially flat nozzle body surface;
• a nozzle heater having a substantially flat heater substrate and a first film heater element patterned on said heater substrate along a portion of said nozzle melt channel;
• and
• means to attach said nozzle heater to said substantially flat nozzle body surface,
• wherein said nozzle heater further includes a second film heater independent from the first film heater, and
• wherein said second film heater is patterned on said heater substrate at least partially along the same portion of said nozzle melt channel.