| 摘要 |
A wrench has a head portion ( 10 ) adapted to engage and apply torque to a workpiece, including a ring member ( 14 ) which surrounds the workpiece and has a fixed end ( 16 ) and a free end ( 18 ) such that, when the ring engages a workpiece and a torque is applied in a predetermined direction ( 48 ), the ring closes around the workpiece, increasing the grip between the wrench and the workpiece even if the workpiece is substantially worn, damaged or undersized. |
