| 摘要 |
PURPOSE:To improve steering stability and travel performance with four-wheel steering by controlling a rear wheel steering angle so as to maintain the same state as before the start of a vehicle or the like, when a steering angle at the start is within the opposite phase steering zone of the rear wheel. CONSTITUTION:In a four-wheel steering vehicle, front wheels 9 are steered by a front wheel steering mechanism 1, according to the operation of a steering wheel 3, and rear wheels 19 are steered to a phase opposite to the phase of the front wheels 9 with a rear wheel steering mechanism 10 under the predetermined condition. Also, the rear wheel steering mechanism 10 is actuated and controlled by a control means 20 via an electric motor 21 on the basis of each detected signal from a steering angle sensor 23 and a shift position sensor 38. In this case, when a steering angle is within the opposite phase steering zone of the rear wheels 19 at the start of the vehicle, the steering angle of the rear wheels 19 is maintained at the same state as before the start. On the other hand, when the rear wheels 19 are steered to the opposite phase, the opposite phase steering angle thereof is maintained, regardless of a shift change among the first, reverse and neutral positions. |
