| 摘要 |
A rock drilling apparatus comprises a hydraulically rotated drill, a percussion motor having a piston which transfers impact energy to the drill, the piston defining together with the machine housing first and second pressure chambers for receiving pressure liquid to move the piston, the percussion motor having a hydraulic circuit including a high pressure side and a low pressure side, a pressure liquid distributing valve having a control input for receiving a control pressure, the distributing valve being located in the hydraulic circuit of the percussion motor for alternately connecting at least one of the pressure chambers to the high pressure side and low pressure side, respectively, of the hydraulic circuit in response to the control pressure, the hydraulic circuit for rotating the drill being separate from the hydraulic circuit of the percussion motor and including a high pressure side and a low pressure side separate from the high and low pressure sides of the percussion motor, a control valve for controlling the control pressure in response to the pressure at the high pressure side of said rotary motor. |
