Patent ID: 7175419
Filing Date: 2007-02-13
Classification: B29C

Abstract:
1. An injection molding apparatus comprising: a first manifold having a first manifold channel for receiving a first melt stream of moldable material under pressure, said first manifold channel having a first outlet for delivering the first melt stream to a first nozzle channel of a nozzle; a second manifold having a second manifold channel for receiving a second melt stream of moldable material under pressure, said second manifold channel having a second outlet for delivering the second melt stream to a second nozzle channel of said nozzle; a mold cavity receiving said first melt stream and said second melt stream from said nozzle, said first nozzle channel and second nozzle channel communicating with said mold cavity through a mold gate; a gating mechanism for selectively enabling communication between said first nozzle channel, said second nozzle channel and said mold gate; an injection piston extending through an injection channel located between said first outlet of said first manifold channel and said first nozzle channel of said nozzle, said injection piston being slidable through said injection channel and having an outer wall for abutting an inner wall of said injection channel, said injection piston being movable from a retracted position enabling communication between said first outlet of said first manifold channel to an extended position blocking said first outlet of said first manifold channel; wherein movement of said injection piston towards said extended position forces melt located in a melt chamber of said first nozzle channel to flow into said mold cavity.