| 摘要 |
PROBLEM TO BE SOLVED: To restrain the consumption of an useless energy of a pump by that an operation oil is passed through a peculiar throttle, when the discharge amount of a variable capacity pump is changed. SOLUTION: A variable capacity pump 1 having a change means 2 for changing a discharge amount is installed and an operation oil pressure passage 3 for introducing the operation oil discharged from this variable capacity pump 1 to an actuator 4 is installed. A control orifice 5 is installed on the way of this operation oil pressure passage 4. A first control device 21 provided with a first piston 22 connected to the change means 2, a first control oil room 23 and a second control oil room 24 is installed. The operation oil of the more downstream side than the control orifice 5 is introduced in the first control oil room 23 and the operation oil of the upperstream side is introduced in the second control oil room 24. A second control device 36 provided with a second piston 37 connected to the change means 5, a third control oil room 38 and a fourth control oil room 39 is installed. The operation oil of the downstream side is introduced in the third control oil room 38 and an atmospheric pressure is introduced in the fourth control oil room 39. |
