| 摘要 |
A hydraulic rotary and percussive device, for example a hand-held hammer or a rock drill, comprises hydraulic reciprocatory percussive means and hydraulic rotary drive means. The means are connected in series hydraulically with the rotary drive means on the exhaust side of the reciprocatory percussive means. The rotary drive means comprise a drive motor actuated by an exhaust pressure pulse on the return stroke of the reciprocatory percussive means, a rotary bush in which a tool is received and a ratchet mechanism coupling the motor to the bush. Valve means are provided by which the rotary drive means can selectively be rendered operative or inoperative. |
