JPH0233785U

JPH0233785U -

Info

Publication number: JPH0233785U
Application number: JP11386988U
Authority: JP
Priority date: 1988-08-30
Filing date: 1988-08-30
Publication date: 1990-03-02

Description

[Brief explanation of drawings]

第１図はこの考案の実施例を示す構成図、第２
図はコントローラの制御動作の一例を示すフロー
チヤートである。１……後輪、６……後輪アクチユエータ、７，
９，１４……電磁弁、１０……ステアリングロツ
クアクチユエータ、１３……タンク、１５……可
変オリフイス、１６……コントローラ。 Figure 1 is a configuration diagram showing an embodiment of this invention, Figure 2
The figure is a flowchart showing an example of the control operation of the controller. 1... Rear wheel, 6... Rear wheel actuator, 7,
9, 14... Solenoid valve, 10... Steering lock actuator, 13... Tank, 15... Variable orifice, 16... Controller.

Claims

[Scope of utility model registration request]

A rear wheel actuator that steers the rear wheels, a directional flow control valve that controls hydraulic pressure to this actuator, and a rear wheel steering angle control circuit that steers the rear wheels according to the steering angle of the front wheels via the directional flow control valve. In a four-wheel steering vehicle equipped with a steering lock actuator, the piston rod extends due to the spring force of a return spring when the hydraulic pressure in the working pressure chamber is released, and the steering lock actuator restricts the steering of the rear wheels to a neutral position. A switching valve that selectively connects the working pressure chamber to the pump side and the tank side, a variable orifice that adjusts the flow of hydraulic pressure from the steering lock actuator to the tank side, and a switching valve that is used in the event of a failure such as a hydraulic pressure failure. A rear wheel neutral lock for a four-wheel steering vehicle, characterized in that a back-up control circuit is provided to release the hydraulic pressure in the working pressure chamber of the steering lock actuator to the tank side through the back-up control circuit and to reduce the orifice diameter of the variable orifice. Device.