Apparatus for retaining a workpiece

A collet clamp assembly comprising:

• an arbor configured to be fixed to a workpiece support, the arbor includes an outer surface;
• a collet located adjacent the outer surface of the arbor and configured to move relative to the outer surface of the arbor in an axial direction between a released position and a clamped position such that the collet expands in a radial direction perpendicular to the axial direction when the collet moves toward the clamped position and the collet contracts in the radial direction when the collet moves toward the released position;
• and
• a threaded screw actuator mechanism including:
• a support fixed to the arbor, the support includes a hollow passage extending through the support in the axial direction, the hollow passage includes a first inner circumferential portion that includes internal threads and a second inner circumferential portion that is a smooth cylindrical inner surface;
• a drawbar connected to the collet, the drawbar extends into the hollow passage, the drawbar has a first outer circumferential portion and a second outer circumferential portion, and the second outer circumferential portion is a smooth cylindrical outer surface that opposes the smooth cylindrical inner surface of the second inner circumferential portion of the support;
• a socket surrounding the first outer circumferential portion of the drawbar and terminating at first and second ends, the socket includes external threads engaging the internal threads on the first inner circumferential portion of the support such that rotation of the socket relative to the support displaces the socket in the axial direction;
• a first thrust bearing rotatably supporting the first end of the socket on the drawbar to allow the socket to rotate relative to the drawbar;
• and
• a second thrust bearing rotatably supporting the second end of the socket on the drawbar to allow the socket to rotate relative to the drawbar, and
• the socket, support, and drawbar are configured such that rotation of the socket in a first direction relative to the support displaces the drawbar in the axial direction such that the drawbar moves the collet toward the released position and rotation of the socket in a second direction different from the first direction and relative to the support displaces the drawbar in the axial direction such that the drawbar moves the collet toward the clamped position.

A pallet assembly for removably securing a workpiece, the pallet assembly comprising:

• a workpiece pallet including a mounting surface, at least one recess, and at least one mounting hole adjacent to the recess;
• and
• at least one collet clamp assembly configured to selectively clamp a workpiece to the workpiece pallet, the collet clamp assembly including:
• an arbor connected to the workpiece pallet, and including an outer surface;
• a collet located adjacent on the outer surface of the arbor and movable relative to the outer surface of the arbor in an axial direction between a released position and a clamped position such that the collet expands in a radial direction perpendicular to the axial direction when the collet moves toward the clamped position and the collet contracts in the radial direction when the collet moves toward the released position;
• and
• a threaded screw actuator mechanism extending into recess and including:
• a support fixed to the arbor, the support includes a hollow passage extending through the support in the axial direction, the hollow passage includes a first inner circumferential portion that includes internal threads and a second inner circumferential portion;
• a drawbar connected to the collet, the drawbar extends into the hollow passage, the drawbar has a first outer circumferential portion and a second outer circumferential portion, and the second outer circumferential portion opposes and is spaced away from the second inner circumferential portion of the support;
• a socket surrounding the first outer circumferential portion of the drawbar and terminating at first and second ends, the socket includes external threads engaging the internal threads on the first inner circumferential portion of the support such that rotation of the socket relative to the support displaces the socket in the axial direction;
• a first thrust bearing rotatably supporting the first end of the socket on the drawbar to allow the socket to rotate relative to the drawbar;
• and
• a second thrust bearing rotatably supporting the second end of the socket on the drawbar to allow the socket to rotate relative to the drawbar, and
• the socket, support, and drawbar are configured such that rotation of the socket in a first direction relative to the support displaces the drawbar in the axial direction such that the drawbar moves the collet toward the released position and rotation of the socket in a second direction different from the first direction and relative to the support displaces the drawbar in the axial direction such that the drawbar moves the collet toward the clamped position.