| 摘要 |
PURPOSE:To always assure stable control of a fluid control device by feeding oil to be delivered from an auxiliary pump and oil to be delivered from a variable delivery rate pump selectively to a control valve by means of a position switching means and controlling pressurized oil to be supplied to the control cylinder of the variable delivery rate pump by means of this control valve. CONSTITUTION:A fluid control device 1 is constructed integrally of a swash plate type variable delivery rate pump (main pump) 2 driven by a motor 12 and an auxiliary pump 6. The auxiliary pump 6 is so constructed that a rotary shaft 18 used commonly for the main pump 2 and the auxiliary pump 6 is supported pivotally in a casing 3 and a rotor 33 provided with multiple vanes is closely fitted in a space P formed inside a cover-like casing 3b. An oil to be delivered from the auxiliary pump 6 and a pressurized oil to be supplied from the main pump 2 through a port 29b are selectively fed to a control valve 4 by a switching means 7, and a control cylinder 3 is driven by the pressurized oil through the control valve 4 to vary the angle of the swash plate 22 in the main pump 2, i.e., the discharge rate of the main pump 2. |
