Actuator apparatus and method enabling multiple piston velocities

1. An injection molding apparatus comprising an injection machine, a manifold, a mold, a clamp plate, an actuator interconnected to a valve pin and an actuator controller,

the actuator comprising an actuator housing having a drive piston disposed within a drive piston bore, the drive piston dividing the drive piston bore into an upstream fluid drive chamber communicating with a source of drive fluid through an upstream drive fluid channel and a downstream fluid drive chamber communicating with the source of drive fluid through a downstream drive fluid channel,

the actuator controller comprising a controller housing having a drive fluid receiving channel that receives drive fluid exiting the upstream fluid drive chamber of the actuator,

the controller housing including a controller piston adapted to control upstream flow of drive fluid from the upstream fluid drive chamber such that the rate of travel of the drive piston is selectively adjustable to a first rate of travel or velocity over the course of travel of the drive piston from a gate closed position to a predetermined intermediate upstream position of upstream travel and such that the rate of travel of the drive piston over the course of travel of the drive piston beyond the predetermined intermediate upstream position is a second rate of travel or velocity that is higher than the first rate of travel or velocity,

wherein the controller piston is reciprocally drivable in a forward and a backward direction through a controller piston bore, the controller housing and the controller piston being adapted to route drive fluid that exits the upstream fluid drive chamber of the actuator to exert a drive fluid force that drives the controller piston upstream through a predetermined path of upstream controller travel in the forward direction through the controller piston bore such that drive fluid is routed through the controller housing to the source at a first rate of flow, the controller housing being further adapted to route drive fluid to the source at a second rate of flow that is higher than the first rate of flow after the controller piston has travelled through the predetermined path of controller travel, and,

wherein the controller piston bore is divided by the controller piston into a downstream controller chamber that receives the drive fluid exiting the upstream fluid drive chamber and an upstream controller chamber that routes drive fluid to the source via a restriction channel that has a metering valve that is controllably adjustable to enable a user to selectively vary the first rate of flow.

2. The apparatus of claim 1 wherein the actuator controller includes a travel length adjuster that is actuatable by a user to selectively adjust the length of travel of the drive piston from the gate closed position to the predetermined intermediate upstream position of upstream travel.

3. Apparatus according to claim 1 wherein the actuator controller includes a velocity adjuster that is actuatable by a user to selectively adjust the rate of travel or velocity of the drive piston over the course of travel of the drive piston from the gate closed position to the predetermined intermediate upstream position of upstream travel.

4. Apparatus according to claim 1 wherein the metering valve is disposed in a first fluid path to the source and the controller housing includes a second fluid path through which drive fluid flows at the second rate of flow to the source.

5. Apparatus according to claim 1 wherein the controller housing includes a first drive fluid channel route that routes drive fluid at the first rate of flow to the source and a second channel route that routes drive fluid to the source at the second rate of flow.

6. Apparatus according to claim 1 wherein the controller housing is adapted to route drive fluid downstream to the upstream fluid drive chamber such that the drive piston travels at a single velocity over the course of downstream travel from an upstream-most position to the gate closed position.

7. Apparatus according to claim 1 wherein the actuator controller includes a spring adapted to constantly urge the controller piston downstream in the backward direction toward an injection cycle start position, the spring exerting a spring force on the controller piston that is substantially less than the drive fluid force of the drive fluid exiting the upstream fluid drive chamber such that the drive fluid exiting the upstream fluid drive chamber readily drives the controller piston upstream in the forward direction.

8. Method of driving the drive piston in the apparatus of claim 1 upstream from the gate closed position at multiple upstream velocities over the course of an injection cycle.

9. An injection molding apparatus comprising an injection machine, a manifold, a mold, a clamp plate, an actuator interconnected to a valve pin and an actuator controller,

the actuator comprising an actuator housing having a drive piston disposed within a drive piston bore, the drive piston dividing the drive piston bore into an upstream fluid drive chamber communicating with a source of drive fluid through an upstream drive fluid channel and a downstream fluid drive chamber communicating with the source of drive fluid through a downstream drive fluid channel,

the actuator controller comprising a controller housing containing a controller piston reciprocally drivable in a forward and a backward direction through a controller piston bore divided into a downstream controller chamber and an upstream controller chamber,

the controller housing including a first drive fluid port that routes drive fluid between the upstream fluid drive chamber of the actuator and the downstream controller chamber of the actuator controller and a second drive fluid port interconnected to the source of drive fluid that receives drive fluid from the upstream controller chamber of the actuator controller,

the controller housing being adapted to route drive fluid that exits the upstream fluid drive chamber of the actuator to drive the controller piston under a drive fluid force through a path of controller travel during which drive fluid is routed through the controller housing to the second drive fluid port at a first rate of flow, the controller housing being further adapted to route drive fluid through the controller housing to the second drive fluid port at a second rate of flow that is higher than the first rate of flow after the controller piston has travelled through the path of travel,

wherein the controller piston bore is divided by the controller piston into the downstream controller chamber that receives the drive fluid exiting the upstream fluid drive chamber and an upstream controller chamber that routes drive fluid to the source via a restriction channel that has a metering valve that controllably restricts flow of the drive fluid to the first rate of flow.

10. An apparatus according to claim 9 wherein the controller housing is adapted to enable the rate of travel of the drive piston to be selectively adjustable to a first rate of travel or velocity over the course of travel of the drive piston from the gate closed position to the predetermined intermediate position of upstream travel and to adjust the rate of travel of the drive piston over the course of travel of the drive piston beyond the predetermined intermediate upstream position to a second rate of travel or velocity that is higher than the first rate of travel or velocity.

11. Apparatus according to claim 9 wherein the actuator controller includes a travel length adjuster that is actuatable by a user to selectively adjust the length of travel of the drive piston from the gate closed position to the predetermined intermediate position of upstream travel.

12. Apparatus according to claim 9 wherein the actuator controller includes a velocity adjuster that is actuatable by a user to selectively adjust the rate of travel or velocity of the drive piston over a course of travel of the drive piston from the gate closed position to a predetermined position of upstream travel.

13. Apparatus according to claim 12 wherein the velocity adjuster is controllably adjustable to restrict flow of the drive fluid to a selectable rate of restricted flow.

14. Apparatus according to claim 9 wherein the controller housing includes a diversion channel that interconnects to the downstream controller chamber when the controller piston has travelled through the path of controller travel, the diversion channel being adapted to enable flow of the drive fluid to the source at the second rate of flow.

15. Apparatus according to claim 9 wherein the controller housing includes a first drive fluid channel route that routes drive fluid at the first rate of flow to the source and a second channel route that routes drive fluid at the second rate of flow to the source.

16. Apparatus according to claim 9 wherein the controller housing is adapted to route drive fluid downstream to the upstream fluid drive chamber such that the drive piston travels at a single velocity over the course of downstream travel from an upstream-most position to the gate closed position.

17. Apparatus according to claim 9 wherein the actuator controller includes a spring adapted to constantly urge the controller piston in a downstream in the backward direction toward an injection cycle start position, the spring exerting a spring force on the controller piston that is substantially less than the drive fluid force of the drive fluid exiting the upstream fluid drive chamber such that the drive fluid exiting the upstream fluid drive chamber readily drives the controller piston upstream in the forward direction.

18. Method of driving the drive piston in the apparatus of claim 9 upstream from the gate closed position at multiple upstream velocities over the course of an injection cycle.

19. An injection molding apparatus comprising an injection machine, a manifold, a mold, a clamp plate, an actuator interconnected to a valve pin and an actuator controller,

the actuator comprising an actuator housing having a drive piston disposed within a drive piston bore, the drive piston dividing the drive piston bore into an upstream fluid drive chamber communicating with a source of drive fluid through an upstream drive fluid channel and

a downstream fluid drive chamber communicating with the source of drive fluid through a downstream drive fluid channel,

the actuator controller comprising a controller housing having a drive fluid receiving channel that receives drive fluid exiting the upstream fluid drive chamber of the actuator,

the controller housing including a controller piston adapted to control upstream flow of drive fluid from the upstream fluid drive chamber such that the rate of travel of the drive piston is selectively adjustable to a first rate of travel or velocity over the course of travel of the drive piston from a gate closed position to a predetermined intermediate upstream position of upstream travel and such that the rate of travel of the drive piston over the course of travel of the drive piston beyond the predetermined intermediate upstream position is a second rate of travel or velocity that is higher than the first rate of travel or velocity,

wherein the controller housing and the controller piston are adapted to route drive fluid that exits the upstream fluid drive chamber of the actuator to exert a drive fluid force that drives the controller piston upstream through a predetermined path of controller travel such that drive fluid is routed through the controller housing to the source at a first rate of flow, the controller housing being further adapted to route drive fluid to the source at a second rate of flow that is higher than the first rate of flow after the controller piston has travelled through the predetermined path of controller travel.