PNEUMATICALLY DRIVEN, PIN VELOCITY CONTROLLED INJECTION MOLDING APPARATUS AND METHOD

摘要

An injection molding apparatus comprising: a pneumatically driven actuator having a piston mounted within a fluid sealed chamber for slidable axial movement along or against an interior surface of the fluid sealed chamber via a non-elastomeric engagement or with a non-elastomeric material disposed between the piston and the interior surface of the fluid sealed chamber, the piston forming first and second drive chambers within the fluid sealed chamber, each drive chamber having respective fluid flow ports, a source of pressurized gas that generates gas flow at a selected maximum pressure or flow rate, a gas metering mechanism, a controller interconnected to the gas metering mechanism, the controller controllabiy moving the gas metering mechanism to selectable positions that correspond to reduced pressures or reduced flow rates during the course of pin travel from the fully downstream gate closed position to the fully upstream gate open position.