| 摘要 |
<p>PURPOSE:To prevent a loss of energy and occurrence of a noise, by interposing a solenoid valve between a servo valve and piston in a delivery amount control mechanism and obtaining a delivery amount to 0 when oil hydraulic actuators are not in operation. CONSTITUTION:A solenoid valve 29 is provided in a pipe line of a servo valve 10 and piston 8, and this solenoid valve 29 is electrically connected to a selector lever 13a. When the solenoid valve 29 is not excited, the servo valve 10 is communicated to the piston 8, when the solenoid valve is excited, both ends of the pison 8 are short-circuited to disconnect communication. Then said solenoid valve 29 is excited when the selector lever 13a is placed in a nautral position. Accordingly, at closing of open-close valves 4, 5, that is, at non-operation of actuators 2, 3, a swash plate 7 in a pump 1 is placed in neutral, and a deilivery amount becomes zero.</p> |
