| 摘要 |
A chuck for holding and driving fasteners such as screws or nails comprises a spring-loaded bearing sleeve with fastener-clamping balls and a spring-loaded clamping sleeve tapered to constrict the balls around the shank of a fastener inserted into the chuck, the clamping sleeve having a space to receive the balls during insertion of the fastener and for releasing the fastener, after completion of the driving operation. |
