INJECTION MOLDING FLOW CONTROL APPARATUS AND METHOD

摘要

An apparatus for controlling the rate of flow of fluid mold material from an injection molding machine to a mold cavity, the apparatus comprising: a manifold having a delivery channel that delivers fluid material to a first gate; an actuator interconnected to a valve pin having a tip end drivable along a drive path that extends between a first position, a second position upstream of the first position and a third position upstream of the second position, the actuator and the valve pin being translationally driven at a controllable rate of travel by a valve system that is controllably adjustable between a start position, one or more intermediate drive rate positions and a high drive rate position, the valve system comprising a source of valve drive fluid that pumps the drive fluid at a maximum drive rate, a first valve interconnected to the source that is selectively adjustable to adjust rate of flow of the drive fluid from the source to a selected less than maximum drive rate and a second valve controllably movable between a first position and a second position; a controller instructing the valve system to drive the actuator and the valve pin continuously upstream from the start position to the second position to the third position; the controller including instructions that instruct the second valve to move from the second position to the first position on receipt by the controller of a signal that is indicative of the valve pin having reached the second position or an elapse of a predetermined amount of time.