| 摘要 |
PCT No. PCT/SE84/00379 Sec. 371 Date Jun. 18, 1985 Sec. 102(e) Date Jun. 18, 1985 PCT Filed Nov. 7, 1984 PCT Pub. No. WO85/02233 PCT Pub. Date May 23, 1985.An arrangement for supplying pilot oil to a servo-valve arranged to activate a main valve of a hydraulic system. The hydraulic system also includes a hydraulic oil pump, a valve located between the pump and the main valve, a pressure reducing valve located between the pump and the servo-valve, and at least one auxiliary assembly is arranged to deliver an electric signal to electromagnetic means arranged to activate the servo-valve. In accordance with the invention, the valve located between the pump and the main valve is arranged to be substantially or fully closed when standing at a given, pre-determined pressure corresponding to the servo pressure required by the servo-valve in order to carry out its intended function, and is arranged to be open when the pressure slightly exceeds the aforementioned pre-determined pressure. An electromagnetically operable shunt valve is located between the pump and pressure reducing valve and, when open, to pass oil direct from the pump to a tank. The shunt valve is arranged to take its closed position upon receipt of a signal delivered from the auxiliary assembly when same is activated in turn, to activate the servo-valve more than one auxiliary assembly can be used. |
