| 摘要 |
PURPOSE:To change a pulsation pressure in a piston chamber so as to reduce production of noise by generating a control signal having a functional relation with a basic frequency of the pulsation pressure in the piston chamber, and controlling a fluid pressure in driving a stroke control member. CONSTITUTION:For a variable displacement pump where the stroke of a plurality of pistons 2 engaged freely reciprocally in a cylinder block 2 is controlled by a stroke control member of an inclined plate 5, the inclined plate 5 has its inclination angle adjusted by action of a bias cylinder 7 which applies a bias force to an operation cylinder 6 and the inclined plate 5 receiving a discharge fluid pressure. In this case, a control device 12 generates a control signal having a functional relation with the basic frequency of a pulsation pressure in a piston chamber relating to noise. A servo valve 13 is controlled by this control signal to control a fluid pressure, and a controlled fluid pressure is supplied to the bias cylinder 7 to control an inclination angle of the inclined plate 5. |
