| 摘要 |
<p>The invention relates to a hydraulic rock breaking device, a protection valve and a method of operating a hydraulic rock breaking device. The rock breaking device comprises a percussion device (4) to which pressure fluid is fed along an inlet channel (13). The inlet channel is provided with a protection valve (23) arranged to monitor the volume flow of pressure fluid flowing through it. If the flow is larger than what has been preset, the protection valve closes, at least partly, the connection through it, protecting thus the percussion device against too high an input power. The protection valve comprises a throttle (38) which generates a pressure difference the magnitude of which is dependent on the fed volume flow. Information on the pressure difference is utilized in controlling the protection valve.</p> |
