| 摘要 |
1,139,096. Chucks. PAUL FORKARDT K.G. 13 May, 1966 [22, May, 1965], No. 21281/66. Heading B3B. In a self-centring chuck the jaws of which are radially displaceable by means of levers 3 operated by a central axially displaceable piston 4, each lever has two coaxial cylindrical journals 5, 6 constituting a short lever arm and located in a bore 2a in the corresponding jaw carrier 2, the axis about which the lever turns being offset in the axial direction of the chuck from the axis of the bore, the jaw carrier 2 being recessed at its side opposite the face which carries, the jaw, as at 2b for the long arm of the lever and one of the two remaining walls of the jaw carrier being cut away at the rear of the journal bore by approximately the breadth of the long lever arm. In the end surface of each of the two journals 5, 6 of each lever, a transverse groove 9 is provided into each of which a corresponding blade 10 is introduced parallel to the journal axis, the blades being located on the ends of cylindrical bearing pins 11 rotatably mounted in a bore 1a in the chuck body parallel to the bore 2a but offset rearwardly therefrom in the axial direction of the chuck by a distance corresponding to the length of the required short arm of the lever 3. The two bearings associated with a lever 3 are connected with the lever 3 by a screw 12. On movement of the piston 4 to the left from the position shown in Fig. 1, the lever 3 swings in clockwise direction about the axis of the bore 1a so that the jaw carrier 2 is displaced radially inwards. In a modification (Fig. 3, not shown) the position of the bore 1b in the chuck body is offset forwardly from the axis of the bore 2a so that a displacement of the piston 4 to the left produces an outward jaw movement. In another modification (Fig. 4, not shown) the bearing pins 11 are mounted eccentrically in bushes 13 which are rotatably mounted in the chuck body and can be held in various angular positions by screws 14 so that the extent and direction of movement of the chuck jaws can be varied. |
