Rear steering apparatus for four-wheel steering cars

Four-wheel steering vehicle rear wheel steering apparatus according to the present invention by returning the rear wheels to calculate the return speed of the rear wheels suitable for addition, the vehicle speed and also self test failure or absence of a rear wheel steering apparatus in a running state, the burden of the operation of the knob to the driver and a phase control mechanism for synthesizing the rotation with the rotation of the bevel gear 29 of the control yoke 25 in order to avoid feeling the encoder to feedback on the rotational angular velocity controller 30 of the control motor 24 to the phase controller on-site and , according to the control valve 23 which is opened and closed according to the control amount of the phase control mechanism, four-wheel steering vehicle rear wheel steering apparatus comprising a left and right moving power cylinder 21 which is in accordance with the movement of the control valve (23) , the power cylinder 21 is a four-wheel steering vehicle, characterized in that Potency air meter 31 is installed is connected to feed back the operation amount of displacement of the power cylinder 21 It provides a rear wheel steering apparatus. The control operation amount of the phase control device; and the step of inputting an operation amount (PS) of the power cylinder 21, the phase control mechanism (40) for inputting a control operation amount (MS) of 40 ( MS) and the step of determining the operation amount (PS) is equal to the power cylinder 21, the above two values ​​(MS, PS), the control valve in accordance with the steps and the vehicle entering the vehicle speed when it is determined different from each other, 23 and the step of computing a corrected operation amount (C), and a step in which the power cylinder 21 works in accordance with the operation amount of the control valve 23, the operation amount of displacement (PC) of the power cylinder 21 determining the step of the input and corrected operation amount (C) and the power cylinder (21) operating the displacement amount (PC) of the control valve 23 is the same is determined; and the above two values ​​(C, PC) are equal to each other and ends when the four-wheel steering vehicle, characterized in that step consisting of the vehicle speed that is returned to the input step, when it is determined different from each other, It provides a control method for a steering wheel unit.