Adjustable valve pin actuator for an injection molding apparatus

A method of adjusting an axial position of a valve pin of an injection molding apparatus, comprising:

• providing an adjustment piece coupled to said valve pin, wherein said adjustment piece moves in an axial direction with respect to a piston of a valve pin actuator;
• allowing said valve pin to move with respect to said piston by removing a locking device from said valve pin actuator;
• moving said adjustment piece relative to said piston a predetermined distance
• measuring said predetermined distance via an indicator to determine movement of said valve pin;
• and
• restricting additional movement of said adjustment piece by replacing said locking device.

An injection molding apparatus, comprising:

• a manifold including a manifold melt channel;
• a nozzle including a nozzle melt channel in communication with said manifold melt channel;
• a valve pin driven by a piston of an actuator, wherein said actuator retracts and extends said valve pin towards a mold gate;
• an adjustment piece that is movable in an axial direction with respect to said piston and that is coupled to said valve pin;
• a locking device including a threaded bore in said adjustment piece, wherein a bolt is threadedly engaged with said threaded bore and said bolt selectively engages an upper surface of said piston to hold adjustment piece from rotating with respect to said piston;
• and
• an indicator of a first axial position of said adjustment piece with respect to said piston, said first axial position of said adjustment piece corresponding to a second axial position of said valve pin with respect to said mold gate.

An injection molding apparatus, comprising:

• a manifold including a manifold melt channel;
• a nozzle including a nozzle melt channel in communication with said manifold melt channel;
• a valve pin driven by a piston of an actuators, wherein said actuator retracts and extends said valve pin towards a mold gate;
• an adjustment piece axially movable with respect to said piston, wherein said valve pin is coupled to said adjustment piece and said adjustment piece includes a first set of teeth;
• and
• an indicator that indicates an axial position of said valve pin with respect to said mold gate;
• and
• an adjustment gear rotatably coupled to an upper surface of said piston, wherein said adjustment gear includes a second set of teeth that engages said first set of teeth of said adjustment piece;
• wherein rotation of said adjustment gear causes adjustment piece to rotate with respect to said piston to axially move said adjustment piece and said valve pin with respect to said piston.