| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a power steering device capable of reconciling eliminating of ripple feeling and enhancing of steering followability without enhancing steering angle resolution of a steering angle sensor. <P>SOLUTION: This device is provided with a flow control valve for adjusting flow rate QP of hydraulic fluid led to a power steering output part, and a controller for controlling the flow rate QP according to a steering angle θ detected by the steering angle sensor. The device is provided with a steering angular velocity calculation means 81 for calculating steering angular velocity ω1 by differentiating the steering angle θ, a low-pass filter 82 for inputting the steering angular velocity ω1 and outputting a signal in which a frequency component higher than a cut-off frequency fc is cut as steering angular velocity ω2, a high speed steering time detection means 86 for detecting a high speed steering time having the steering angular velocity ω1 higher than a threshold value ω3, a cut-off frequency changing means 87 for changing the cut-off frequency of the low-pass filter 82 into a higher cut-off frequency at the high speed steering time, and a flow rate control means 80 for controlling the flow rate QP according to at least one of the steering angle θ and the steering angular velocity ω2. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
