Patent ID: 7234929
Filing Date: 2007-06-26
Classification: B29C

Abstract:
1. In a molding machine having a manifold for distributing a melt material flowing under pressure to a channel leading to a gate of a mold cavity wherein the rate of flow of the melt material is determined by positioning of a pin that is controllably movable through the channel to create a gap of controllable size between the pin and the channel, wherein the pin is disposed within the melt material on which the melt material exerts a melt pressure force, an apparatus for controlling positioning of the pin comprising: an actuator adapted to controllably move the pin through the channel and adjust the rate of material flow by positioning of the pin and controlling the size of the gap, the actuator having a piston receiving a force that is exerted on the piston by the melt material through the pin, the piston being adapted to respond to the melt pressure force received through the pin with a predetermined controlling force.