| 摘要 |
PURPOSE:To make it possible to smoothly return rear wheels to their neutral positions, by communicating first and second pressure acting chambers in a rear wheel steering power cylinder through a bypass passage when an electronic system circuit or the like fails. CONSTITUTION:A rear wheel steering power cylinder 2 is provided therein with a control valve 26 and a bypass passage 25 connecting a first pressure acting chamber 22 with a second pressure acting chamber 23. The control valve 26 is disposed in the bypass passage 25, and is applied with electrical current so as to release the bypass passage 25 in its normal condition. When an electronic circuit system becomes abnormal, the control valve 26 is actuated to open the bypass valve 25, thereby the hydraulic pressures in the first and second pressure acting chambers 22, 23 gradually become equal to each other to return rear wheels to their neutral position. |
