Patent ID: 6491305
Filing Date: 2002-12-10
Classification: B23B,Y10T

Abstract:
A chuck comprising:a chuck body capable of being attached to a spindle of a machine tool; a plurality of master jaws attached to the chuck body along the normal of the chuck body and formed with T-shaped grooves extending along the length thereof, a plurality of T nuts having tops and trunks, the tops being slidably fitted in the T-shaped grooves of the master jaws; a plurality of gripping claws having work holding surfaces and grooves for engagement with the trunks of the T nuts; and a plurality of claw attaching members inserted in holes in the T nuts and the gripping claws and used for attaching the gripping claws to the T nuts; wherein: the holes are formed across the T nuts and the gripping claws which are engaged with one another; the claw attaching members include eccentric shafts which have eccentric cams, are rotated and relatively move the T nuts and the gripping claws; the holes in the T nuts are provided with cam parts with which the eccentric cams of the eccentric shafts come into contact; the holes in the T nuts have cam parts with which the cams of the eccentric shafts come into contact, and the cams of the eccentric shafts are positioned in accordance with the holes of the T nuts; and the holes in the T nuts have flat parts and the claw attaching members have flat parts leading to the cam part and facing with the flat parts in the holes in the T nuts.