| 摘要 |
PURPOSE: To provide a power steering system having a satisfactory responsing property to steering aid and an excellent steering feeling. CONSTITUTION: A power steering gear detects a load on a hydraulic pump 5 driven by an electric motor 4 and controllably changes over the rotational speed of the electric motor 4 to high or low speed to aid steering with hydraulic pressure produced by the hydraulic pump 5. There are provided a target rotational speed determining means 1a for determining the target rotational speed of the electric motor 4 on the basis of a load detecting signal to output the indicating signal and a threshold determining means 18 to determine the threshold value of the load detecting signal for changing over the aimed rotational speed to high or low speed on the basis of the indicating signal. The target rotational speed determining means 1a is constituted to determine the target rotational speed of the electric motor 4 according to the threshold determined by the threshold determining means 18. |
