Patent ID: 6290241
Filing Date: 2001-09-18
Classification: B23B,Y10T

Abstract:
A fixed length collet chuck assembly for gripping and releasing a workpiece having a longitudinal, central axis, said assembly comprising:a chuck body disposed about said longitudinal, central axis;a draw tube connector disposed in said chuck body, said draw tube connector being threadedly coupled onto a draw tube of a machine spindle;an actuator connected to said draw tube connector, said actuator being generally cylindrical and having an outer surface which tapers outwardly starting from an end of said actuator closest to said machine spindle;a retaining plate disposed about said draw tube connector and rigidly fixed to said chuck body, said retaining plate limiting axial movement of said actuator;a taper ring disposed about said actuator and including a first annular surface facing toward said machine spindle and an opposed second annular surface facing away from said machine spindle, said first annular surface inclined relative to said longitudinal, central axis and outwardly from said axis toward said machine spindle, with said actuator, said retaining plate, and said taper ring defining a channel;a plurality of ball bearings disposed within said channel;a bushing ring disposed about said draw tube connector adjacent to said taper ring;a plurality of bushings coupled to said bushing ring and extending axially in the direction away from said machine spindle;a collet sleeve disposed in said chuck body and coupled to a free end of said bushings, said collet sleeve being generally cylindrical and having an inner surface that tapers outwardly from said longitudinal, central axis starting at the end of said collet sleeve closest to said machine spindle; anda generally cylindrical collet including an inner and outer surface, wherein said outer surface tapers in a direction opposite of said inner surface of said collet sleeve and wherein said collet is slidingly engageable with said collet sleeve whereby, upon actuation of said draw tube, said collet sleeve moves axially away from said machine spindle engaging said collet causing said collet to radially collapse upon a workpiece.