| 摘要 |
PURPOSE:To make improvements in steerability, by making a control value of an oil flow rate on the basis of a car speed signal a fixed value till it reaches the specified car speed, and afterward, decreasing it with increment of the car speed. CONSTITUTION:At the time of car driving, a car speed signal out of a car speed sensor 1 is fed to a solenoid drive circuit 4 via a voltage conversion circuit 2 and a smoothing amplification circuit 3. At this time, size of DC voltage to be secured out of the voltage conversion circuit 2 is the smaller the larger in a car speed, while an oil flow rate to be fed to a power steering via a solenoid valve to be connected to output terminals SOL 1 and 2 is controlled to be large at low speed but small at high speed, respectively. A car speed-output voltage characteristic of an operational amplifier 3j in the said voltage conversion circuit 2 is set so as to keep its output voltage constant till the car speed reaches the specified car speed V1, and afterward to be decreased with increment of the car speed, so that the oil flow rate should be kept constant at less than the specified car speed V1. |
