| 摘要 |
PURPOSE:To provide a power steering allowing stable steering feelings to be obtained with a little steering torque change caused by the ground load change of steered wheels. CONSTITUTION:The higher the vehicle speed, the more becomes the exciting current quantity of a solenoid valve to reduce assisting torque. The ground load W of front wheels, steered wheels, is computed from the oil pressure of a hydraulic cylinder forming a suspension, and the initial ground load Wo in the case of an ignition switch being turned on is subtracted to compute variation W (S1-S3). A solenoid exciting current correction factor I1 is computed on the basis of the variation W (S4), and a solenoid exciting current I2 determined according to the vehicle speed V is corrected (S7). The correction factor I1 is so set as to make assisting toque larger as the ground load W is larger than the initial ground load Wo and to make assisting torque smaller as the ground load W is smaller than the initial ground load Wo. Accordingly, even if the ground load is increased/decreased, the change of steering torque caused by this increase/decrease is reduced or nullified. |
