Valve pin actuator

A valve pin actuator for use in an injection molding system adapted for mounting between a plastic distribution manifold and an overlying clamping plate, the valve pin actuator coupled to a valve pin adapted to extend through an injection nozzle and positioned to seat and unseat at a mold gate, said valve pin actuator comprising:

• a cylinder mounted to the clamping plate;
• a piston slidably mounted in the cylinder;
• a valve pin assembly carried by the piston and for holding a top end of the valve pin;
• and
• a circuit coupled to said piston to control sliding movement thereof and in turn translation of said valve pin between the seated and unseated positions;
• said valve pin assembly including;
• a first part removably secured to the piston so as to translate therewith, the first part including an actuator cap;
• and a second part for receiving said valve pin and secured to said manifold, the second part including an actuator support and means for securing the actuator support to the top of the manifold;
• wherein the valve pin includes a pin head secured to the actuator cap.

A valve pin actuator for use in an injection molding system adapted for mounting between a plastic distribution manifold and an overlying clamping plate, the valve pin actuator coupled to a valve pin adapted to extend through an injection nozzle and positioned to seat and unseat at a mold gate, said valve pin actuator comprising:

• a cylinder mounted to the clamping plate;
• a piston slidably mounted in the cylinder;
• a valve pin assembly carried by the piston and for holding a top end of the valve pin;
• and
• a circuit coupled to said piston to control sliding movement thereof and in turn translation of said valve pin between the seated and unseated positions, wherein said circuit is a hydraulic circuit and includes:
• first and second hydraulic lines for respectively providing pressurized fluid to first and second chambers, wherein during operation of the hydraulic circuit, one line is pressurized, and one line is not pressurized;
• a check pin disposed between the first and second chambers that permits flow from said first chamber to said second chamber when said first hydraulic line is pressurized, and blocks flow from said second chamber to said first chamber when said second hydraulic line is pressurized;
• said valve pin assembly including;
• a first part removably secured to the piston so as to translate therewith;
• and a second part for receiving said valve pin and secured to said manifold .