| 摘要 |
PURPOSE:To perform a precise machining by preventing distortion and flaw of a workpiece by means of a diaphragm plate for supporting a finger claw, and a plunger and a spherical bearing seat associated with the diaphragm plate in a finger chuck for a machine tool. CONSTITUTION:When a plunger 8 and a wedge plunger 25 moves in an arrow direction a, a finger claw 2a at an extreme end turns clockwise along a non- illustrated spiral groove of a finger shaft 12 through a diaphragm plate 10. In the same manner, a centering claw 3a mounted on a base jaw 22 moves in a central direction. When a workpiece 46 is loaded and the plunger 8 and the wedge plunger 25 are moved in an arrow direction b inversely, the work piece is gripped by the centering claw 3a and the finger claw 2a from the out side and the inside. At this moment, the action of a counterweight 20 reduces centrifugal force applied to the finger claw 2a for preventing deformation of the work-piece 46 and the diaphragm 10 provided with spherical bearings 11, 16 ensures a uniform gripping regardless of dispersion in the thickness of a workpiece gripping portion. |
