| 摘要 |
PURPOSE:To protect a hydraulic power equipment by closing without delay an inlet valve when RPM of a main engine rises extraodinarily, opening again the inlet valve when operation of guide vanes is normal, and stopping the main engine in case when the guide vanes do not close. CONSTITUTION:A load cut off control apparatus 7, a timer 8 and a protection apparatus 9 are arranged in a hydraulic power engine system. When the load is cut-off, a detector of the load cut-off control apparatus 7 (not shown in chart) detects this situation to operate an inlet valve close-command device (not shown in chart) closing the inlet valve 1. When the guide vanes 2 are normal, they are closed and again the inlet valve 1 opens. On the contrary, when the guide vanes 2 do not close owing to some trouble, a releaser (not shown in chart) of the load cut-off control apparatus 7 is not made ON and so the inlet valve is closed. After a predetermined time elapses, the timer 8 is made ON and the protection apparatus 9 operates to stop the main engine. Consequently, when load is cut-off, rapid increase of RPM of the hydraulic wheel can be controlled promptly as well as useless stopping of operation can be avoided. |
