Collet chuck with run-out adjustment - has ring nut with adjusting set screws bearing against end face of pressure ring that closes collet

摘要

The tool shank (2) is gripped by the collet (1), which fits into the taper bore (4) of a machine tool chuck (5) and is closed by tightening the ring nut (6). Between the ring nut and collet is interposed a pressure ring (7) having a taper bore (9) fitting the front taper (8) of the collet, and a parallel guide bore fitting the nose (12) of the chuck with a small clearance. When the ring nut is tightened, the axial closing force on the collet is exerted through the pressure ring, which is held concentric by the fit of the guide bore on the chuck nose (12). Equally spaced around the end face of the ring nut are set screws (18) which bear against the end of the pressure ring in a shallow track (20). Any remaining run-out of the tool can be reduced to less than 5 micron by appropriate adjustment of the set screws. ADVANTAGE - Run-out of tool can be minimised. Commercially available collets can be used.