Abstract: A power chuck assembly for securing a workpiece as the chuck assembly moves or rotates the workpiece is disclosed. The assembly includes a body portion, at least two gripping members and at least two counterweights wherein said counterweights operate to assist in securing a workpiece upon the chuck assembly.

Abstract: A system for holding workpieces during machining providing a plate to which the workpiece can be rigidly secured. The plate, on its rear face, has a central frusto-conical boss which seats into a complementary central recess in a support member. The support member has plural, radially reciprocal latch members which engage pockets in the boss. A ring rotatably mounted on and surrounding the support member is operatively connected to the latch members for simultaneously extending and retracting them.

Abstract: A chuck for heavy duty applications has a plurality of radially slidable jaw mounts each actuated by an L-shaped lever mounted for rocking motion about a supporting trunnion. The levers each have a leg engaging one of the jaw mounts and another engaging an actuator. An external lubricant receiving port is provided adjacent each trunnion and a multiple conduit lubricant distribution system is provided extending through the supporting trunnion and actuating lever. The chuck body also has a lubricant flow channel through which lubricant flows circumferentially of the chuck to assure uniform distribution, eliminating lubricant concentrations and eccentric weight distribution in the chuck.