| 摘要 |
PROBLEM TO BE SOLVED: To prevent interruption of damping force control and stepping-out of a stepping motor when damping force control is carried out using the stepping motor as a driving source. SOLUTION: A suspension control unit can judge whether a spool action force Ff which acts to a spool 77 by the movement of hydraulic oil exceeds the detent torque of a stepping motor 14, that is to say, whether the stepping motor causes an unforeseen rotation or stepping-out when any treatment is not provided by comparing an upper limit value in an elongation side VP+ and an upper limit value in a contraction side VP- responding to relative velocity VP(n) and an opening of a spool valve at that time. Then, when the present relative velocity VP(n) is other than the relative velocity between the upper limit value in an elongation side VP+ and the upper limit value in a contraction side VP-, (VP(n)>VP+, VP(n)(VP-), it is determined that there is the possibility of stepping-out in the stepping motor 14, and an electric current is applied for holding the present rotating position. |
