| 摘要 |
<p>The invention relates to a percussion device having a body (1a) and a percussion piston (2) moving therein, pressure fluid spaces (3, 4) in the rear and front ends of the percussion piston (2) and pressure fluid channels for feeding pressure fluid into the percussion device. The percussion piston (2) and the control valve (5) comprise surfaces, which, when aligned, substantially close the pressure fluid flow from the pressure fluid space (4) locating behind the percussion piston (2) in front of the control valve (5), whereby the produced pressure displaces the control valve (5) to another position.</p> |
