| 摘要 |
In a hand-held tool, such as a power drill, a hammer drill, a powered screwdriver or the like, a chuck is secured on one end of an axially extending rotary spindle by ball-shaped locking members. The chuck has a driver socket which fits on one end of the rotary spindle. The locking members are located within openings in the driver socket and are displaced radially inwardly into recesses in the spindle by a support ring encircling the driver socket. Recesses in the spindle, in which the locking members are held, have a first surface extending transversely of the axial direction of the spindle with the first surface forming a pair of run-up ramp surfaces, each inclined to the axis of the spindle and relative to one another. Due to the rotation of the spindle, the locking members move along one of the run-up ramp surfaces within each recess and develop a force component in the axial direction of the spindle, pressing abutment surfaces of the spindle and the driver socket into contact with one another. If the direction of rotation is reversed, the ball members move from one run-up ramp surface to the other within the recess and maintain the contact of the abutment surfaces. |
