| 摘要 |
PURPOSE:To save fuel consumption and improve the smooth return of a steering handle by driving an oil pump only when necessary to supply the required amount of pressure fluid. CONSTITUTION:A power steering device is equipped with a direction selector valve 17 for supplying and discharging pressure fluid to and from a power cylinder 30, and an oil pump 40 for delivering the pressure fluid to the supply circuit of the valve 17, according to pump speed. Furthermore, the power steering device is equipped with an electric motor 50 for driving the oil pump 40 at a speed corresponding to the output of torque sensor 15, for delivering an amount of the pressure fluid corresponding to assisting torque, and a bypass control valve 70 for making both chambers of the power cylinder 30 communicate with each other, when the output of the torque sensor 15 drops to or below the predetermined value. |
