摘要 |
A percussion device has a machine housing (1), a forwards and backwards movable percussion piston (2) in the machine housing, and a reciprocatingly movable valve body (6) in the machine housing. The percussion piston has a first (4) and a second (5) driving surface subjected to pressure to drive the percussion piston (2) forwards and backwards. The valve body (6) has a first end surface (12) and a second end surface (13) for driving the valve body in first and second directions by applied pressure. The valve body (6) is arranged over a channel (7) in the machine housing, to connect at least the second (5) driving surface alternately to a pressure source (8) or to low pressure (9), and the second end surface (13) is alternately connectable by the percussion piston (2) to the pressure source (8) or, over a valve device (11) for creating a counter-pressure, to the low pressure (8). |