Patent ID: 6533292
Filing Date: 2003-03-18
Classification: B23B,Y10T

Abstract:
A chuck comprising:a housing with a bore therein that defines a longitudinal axis; a collet disposed within the housing, the collet having a first portion, a collapsible second portion, and a collet bore therein substantially coaxial with the bore of the housing; a ramp body within the bore and surrounding the first portion of the collet, the ramp body having integral securing means for securing the ramp body to the housing, the ramp body having a ramp surface substantially transverse to the longitudinal axis of the housing; second means for securing the collet to the ramp body so that the integral securing means and the second securing means substantially prevent longitudinal movement of the ramp body and the collet within the housing; a piston reciprocable within the bore and surrounding the collet, the piston having a bearing surface adjacent the ramp surface of the ramp body; means for longitudinally actuating the piston within the bore; a wedge within the housing between the ramp surface of the ramp body and the bearing surface of the piston, the wedge having multiple bearing surfaces providing surface-to-surface contact, a first bearing surface camming against the bearing surface of the piston, a second bearing surface camming against the ramp surface of the ramp body, and a third bearing surface, the ramp surface of the ramp body, the bearing surface of the piston, and the first and second bearing surfaces of the wedge being operable to cause the wedge to move radially inward toward the collet when the piston moves toward the ramp body; pusher means within the bore and engaged with the third bearing surface of the wedge for causing the second portion of the collet to collapse radially inward to grip a workpiece disposed within the collet bore when the wedge moves radially inward toward the collet.