Patent ID: 10611403

Abstract:
In order to provide a steering device for a construction/transport/farm machine which can be steered by means of a steering wheel operation and by means of a lever operation (or automatic steering) such that not only can a mechanism for prioritizing the steering wheel operation be achieved with a simple configuration, but the mechanism can also be caused to stably operate, the steering device is provided with: steering cylinders 1; a steering valve 2; a pump 3; a steering wheel control valve 4; an electromagnetic control valve 5 for lever/automatic steering; a steering wheel priority valve 6; and a change-over valve 7 which, upon sensing a load pressure generated when the steering wheel control valve 4 is operated, switches the setting of the steering wheel priority valve 6 by using the load pressure, wherein the change-over valve 7 for switching the setting of the steering wheel priority valve 6 has a two-port two-position configuration whereby a drain oil passage of the steering wheel priority valve 6 is closed by utilizing the load pressure generated when the steering wheel control valve 4 is operated.