| 摘要 |
A chuck (10) transmits the rotational force of an operating ring (17) fitted over a body (11) to a nut ring (15), opening and closing the jaws (12). An input ring (18) is fitted into the inner surface of the operating ring (17) opposing the nut ring (15), and a thrust bearing (22) between the inner side of the input ring (18) and the body (11) positions a ball holder (21) on the body (11) side, forming a ball thread (23) between the inner surface of the input ring (18) and the outer surface of the nut ring (15), which feeds the nut ring (15) in the direction of thrust by balls (27) held in a retainer (26) through the rotation of the input ring (18) in the clamping direction. An inner edge of the nut ring (15) is engaged with the inner surface of the ball holder (21), and a return spring (30) between the operating ring (17) and the nut ring (15) returns the nut ring (15) when the clamping load is released from the nut ring (15). |
