Abstract: A drive assembly for rotating and translating a shaft comprising a hollow shaft motor and a fluid cylinder. The hollow shaft motor rotates the shaft and the fluid cylinder moves the shaft lengthwise. The drive is particularly useful in the injection unit of an injection-molding machine. In one preferred embodiment the injection unit includes a hollow electric motor and a hydraulic cylinder. A first cylinder wall of the hydraulic cylinder is joined to a rotor of the hollow motor. A second cylinder wall of the cylinder is connected to a stationary portion of the hollow motor. A piston has two end portions. One end portion of the piston engages the first cylinder wall and the other end portion of the piston engages the second cylinder wall. Means for rotating the piston are attached to the rotor. The means for rotating also permits the piston end portions to slide along the cylinder walls.

Abstract: Methods for enhanced purging of an injection molding shooting pot assembly are provided. Old melt is purged from a shooting pot having an injection plunger slidably received in an injection cylinder. The plunger is moved by a powered piston, which moves the injection plunger to a purging position. The plunger is then arrested in the purging position. Sufficient new melt is injected through an inlet positioned such that the new melt sweeps substantially an entire volume of the injection cylinder ahead of the injection plunger in flowing between the inlet and a single outlet remote from the inlet.

Abstract: The present invention relates to a device for unloading and cooling molded parts from an injection molding machine having an index turret block rotatable about a central axis. The device comprises a cooling turret block rotatable about an axis substantially parallel to the central axis, which cooling turret block has a plurality of faces. At least one of the faces includes a plurality of nozzles for applying a cooling fluid to surfaces of the molded parts while the molded parts are resident on the index turret block. At least two of the other faces of the cooling turret block include a plurality of receiving tubes for receiving molded parts from the index turret block for further cooling. The cooling turret block of the present invention is capable of cooling multiple sets of molded parts.

Abstract: A pre-plasticizing injection molding machine includes a plasticizing and flow regulating assembly connected to the tip of an injection chamber or shooting pot having an injection cylinder. A distributor valve allows the transfer of plastic resin into the shooting pot at low pressure and prevents the backward flow of resin to the plasticizing unit when the injection plunger injects the resin. A plurality of distribution channels in communication with either the distributor valve or a separate valve, and having outlets in the shooting pot angularly equispaced in proximity to the perimeter of the conical tip of the plunger uniformly distributes new resin behind resin retained in the shooting pot from the previous injection cycle, thereby obviating stagnation zones.