| 摘要 |
PURPOSE:To obtain a hydraulic control device with reduced power loss and smaller occupying space, by carrying out the rotating speed control of the electric motor of a fixed delivery pump by the signal in which the delivery pressure has been corrected by the deviation pressure between the delivery pressure and the load pressure in which the pressure loss has been corrected. CONSTITUTION:An electric motor 1 is coupled with a fixed delivery pump 2 so as to obtain the same rotating speed. The discharge power of the pump 2 being proportional to the rotating speed is output into a main pipe line 6, and is supplied to a load 8 via a solenoid valve 19. The delivery pressure in the main pipe line 6 is input into a first pressure sensor 9, and the load pressure is input into a second pressure sensor 10. The differential pressure equivalent to the pressure loss between the discharge power and the load power is added to the output of the second pressure sensor 10 by a differential pressure correcting unit 11 to obtain the deviation pressure by a differential circuit 12. After the output of the differential circuit 12 in response to the load variation has been input into the output of the first pressure sensor 9, it is input into a control circuit 13 to output a correcting signal. By the output of this signal, the rotating speed control of the motor 1 is carried out, enabling the hydraulic control having been power-matched and with reduced power loss to be carried out. Thus, the deterioration of oil can be reduced, and the volume of each oil tank 3 can be decreased.
|
