Co-injection nozzle assembly

An apparatus for use in a co-injection molding system, comprising:

• a gate adapter body having at least a pair of nozzle passages formed therein, including a first nozzle passage and a second nozzle passage, each extending between an inlet and a passage outlet;
• at least a pair of nozzle assemblies mounted in said adapter body, each of said nozzle assemblies being in fluid communication with a source of liquid extruded material and having a nozzle outlet in fluid communication with an associated one of said nozzle passage inlets;
• a gate body releasably attached to said adapter body and forming a gate outlet in fluid communication with said passage outlets
• an elongated fixed sleeve disposed in said adapter body and having an inside and an outside, said inside of said elongated sleeve being in fluid communication with said first nozzle passage, whereby at least a portion of said second nozzle passage is in fluid communication with said outside of said sleeve;
• and
• a valve stem being at least partially disposed in said elongated sleeve, said valve stem being reciprocatingly movable within said elongated sleeve, said valve stem being operable to selectively:
• i) prevent material flow through each of said first nozzle passage and said second nozzle passage;
• ii) prevent material flow through said first nozzle passage while allowing material flow through said second nozzle passage;
• and iii) allow material flow through each of said first nozzle passage and said second nozzle passage to said gate outlet, wherein a length of said of said nozzle passages is selected to minimize heat transfer between the materials in said nozzle passages.

An apparatus for use in a co-injection molding system, comprising:

• a gate adapter body including at least a pair of nozzle passages formed therein, including a first nozzle passage and a second nozzle passage, each said nozzle passage having an inlet end in fluid communication with a passage outlet;
• an elongated fixed sleeve disposed in said adapter body and having an inside and an outside, said inside of said elongated sleeve being in fluid communication with said first nozzle passage, whereby at least a portion of said second nozzle passage is in fluid communication with said outside of said sleeve;
• and
• a valve stem being at least partially disposed in said elongated sleeve, said valve stem being reciprocatingly movable within said elongated sleeve;
• and
• an actuator connected to said valve stem for selectively:
• i) preventing material flow through each of said first nozzle passage and said second nozzle passage:
• ii) preventing material flow through said first nozzle passage while allowing material flow through said second nozzle passage:
• and iii) allowing material flow through each of said first nozzle passage and said second nozzle passage to said gate outlet, wherein said nozzle passages are configured in length and spacing to minimize thermal transfer between materials in said nozzle passage.