Abstract: A self-compensating support skate (46) for an annular hydraulic ram (15) mounted in the front stationary platen (10) of a “two-platen” injection molding machine (1) is disclosed. The hydraulic ram (15) fits into a central bore (22) in the stationary platen (10) and connects directly to a relatively thin die platen (11) that provides a mold mounting surface. The purpose of the skate (46) is to prevent movement (tilting) of the die platen (11) and the resulting misalignment with the movable platen (20) when the mold (30) is attached. The skate (46) is adjusted during assembly to compensate for the tolerance stack-up in the ram assembly. The “zero” clearance is maintained by disc springs (56) within the skate (46) that compensate for the expansions and contractions of the large diameter parts due to temperature variations. The die platen (11) is held in the aligned position by contact with the lower tie rods (7).

Abstract: A movable platen structure for an injection molding machine in which the platen is in the form of a box-like structure that includes spaced front and rear plates. The platen structure includes a plurality of longitudinally extending beam members that interconnect the front and rear plates and are positioned in parallel relationship and in a generally rectangular array. The rear plate includes on its rear face a plurality of vertically extending pillow block members for pivotally carrying a pivot pin, the pillow block members having inclined sides that intersect with the rear face of the rear plate. Extending across the front face of the rear plate and opposite from the ends of the respective pillow blocks are an upper and a lower transverse beam member, each of which is formed integrally with the rear plate to provide additional structural stiffening and thereby permit the rear plate to be of a thinner and lighter structure.

Abstract: Part ejection apparatus for ejecting molded parts from a mold carried by a movable platen in an injection molding machine. A plurality of linearly operating hydraulic cylinders are provided to move an ejector bar that is carried along guide rods supported by a movable platen so that the ejector bar moves toward and away from a mold member that is carried by the movable platen. Suitable connections can be provided between the ejector bar and the ejection mechanism of the mold to drive ejector pins carried by the mold for separating the molded part from the mold surface. Additionally, a rotary motor is also carried by the movable platen and has its axis coincident with the longitudinal axis of the movable platen for connection of an output shaft of the motor with a drive mechanism carried by a mold, the drive mechanism suitable for rotating rotatable cores that form internal threads on the molded article.