| 摘要 |
<p>PURPOSE:To avoid hazard due to misoperation under running by furnishing a solenoid-operated selector valve for ensuring safety of priority operation provided in a pilot circuit, and putting a left and a right solenoid of this selector valve in communication with a pressure switch for the pilot pressure. CONSTITUTION:A solenoid-operated selector valve 51 for ensuring safety of priority operation is installed in a pilot circuit, which puts a pilot pump 30 in communication with pilot valves 8F, 8B, 9F, 9B, 10F, 10B of normal pedal devices 4, 4 and a pedal device 6 solely devoted to straight running. Pressure switches 54, 55 are furnished to apply the pilot pressures, which are led out of pilot valves 8-10, to the normal pedal device 4 and straight run pedal device 6. The pressure switches 54, 55 are connected with a left and a right solenoid 52, 53 of the selector valve 51 through respective electric paths. This prevents abrupt direction change even though the normal pedal device 4 is stamped and by mistake during running, the straight run pedal device 6 is stamped.</p> |
