Electro Fluid Driven Actuator and Method

An injection molding method, comprising:

• providing a valve pin that is disposed in a flow channel, the flow channel adapted to pass injection fluid though a gate and into a mold cavity;
• providing a first fluid drive cylinder having a first piston that is interconnected to a second fluid drive cylinder having a second piston in an arrangement wherein reciprocating movement of the first piston drives concomitant back and forth movement of the second piston,
• interconnecting the valve pin to the second piston in an arrangement wherein reciprocating movement of the second piston drives concomitant back and forth movement of the valve pin through the flow channel between gate open and gate closed positions,
• providing an electrically powered actuator that is interconnected to the first piston;
• injecting a flow of the injection fluid to a heated manifold;
• distributing the injection fluid, via the heated manifold, to the flow channel;
• driving the first piston reciprocally within the first fluid drive cylinder via the electrically powered actuator according to a drive program that instructs the valve pin to be driven between the gate closed and gate open positions and one or more selected positions therebetween.

An injection molding system comprising:

• an injection molding machine (IMM) that delivers an injection fluid to a heated manifold mounted between a top clamp plate and a mold having a cavity, the heated manifold adapted to distribute the injection fluid to a flow channel that is adapted to pass the injection fluid through a gate to the mold cavity;
• a first fluid drive cylinder having a first piston disposed within the first fluid drive cylinder adapted to be driven reciprocally upstream and downstream within the first fluid drive cylinder;
• a second fluid drive cylinder having a second piston disposed within the second fluid drive cylinder and interconnected to a valve pin
• wherein the first fluid drive cylinder and the second fluid drive cylinder are interconnected in an arrangement wherein reciprocating movement of the first piston drives concomitant back and forth movement of the second piston and concomitant back and forth movement of the valve pin along a selected path of travel (Y) within the flow channel between gate closed and gate open positions;
• an electrically powered actuator adapted to drive the first piston reciprocally within the first fluid drive cylinder according to a program that instructs the valve pin to be driven between the gate closed and gate open positions and one or more selected positions therebetween.