GB1422383A - Chucks - Google Patents

Abstract

1422383 Chucks PAUL FORKARDT 21 Sept 1973 44313/73 Heading B3B A chuck comprises a plurality of jaws radially slidable in a chuck body 1, each jaw including a base jaw 2 and a replaceable gripping jaw 5 which lies in a recess formed in the forward face of the base jaw, or in an intermediate member fixed relative thereto, the base and gripping jaws being radially connected for transmitting clamping loads by co-operating abutment surfaces 6 and being engaged with each other by interlocking holding bars 2a and 5a formed at radially inner ends of the base and gripping jaws 2, 5 and the gripping jaws being secured to the base jaws in the axial direction by spring clamping means which are overcome when a gripping jaw 5 is pulled off for replacement. The spring clamping means comprises a pair of oppositely directed thrust members (8) (Fig. 2, not shown) which are biased by springs (7) to engage detent recesses in the gripping jaws 5. The abutment faces 6 may be arcuate or straight (Fig. 6, not shown) and instead of being formed at the holding bars 2a, 5a, may be formed adjacent the radially outward end of the base and gripping jaws 2, 5 (Fig. 4, not shown). The gripping jaw 5 may have two circumferentially spaced work gripping portions (5c) (Fig. 9, not shown) and be pivotally mounted by means of a pivot recess (2b) and pivot pin (13). The chuck jaws are operated by a spindle drawbar which moves a plunger 3 to actuate the jaws radially through inclined ramps and " wedge-claw " connections.