| 摘要 |
PROBLEM TO BE SOLVED: To prevent the stop of an engine by reducing discharge flow rate of a variable pump when the rotation condition of the engine is at low level. SOLUTION: When an output value of a throttle knob 104 (a voltage value outputted in correspondence to rotation angle of the throttle knob) is lower than a predetermined value, it is judged that the rotation condition of an engine 102 is at low level, a solenoid 120 is changed over to make discharge pressure P1 of a gear pump 122 act on a shuttle valve 124 to produce negative control pressure, and the discharge pressure P1 is inputted into a variable pump 106. As a result, discharge flow rate of the variable pump 106 is reduced. |
