| 摘要 |
PROBLEM TO BE SOLVED: To make steering-controllable a power steering apparatus for a front two-axle vehicle at the time of stoppage of an engine driving type pump or the like. SOLUTION: This apparatus is provided with a main power cylinder 6 and a sub-power cylinder 30 for steering-controlling front and rear steering wheels of a front two-axle vehicle, a main pump 10 driven by an engine of a vehicle a main control valve 15 for switching a flow passage for fluid pressure from the pump 10, a sub-pump 11 driven by a means other than the engine, and a sub-control valve 31 for switching a flow passage for fluid pressure from the sub-pump 11. A pilot type check valve 40 to allow a fluid pressure flow from a return passage 42 a tank 13 to a supply passage 41 to the sub-pump 11 using, as pilot pressure, fluid pressure in a fluid pressure supply passage 43 from the main pump 10 is provided between the the fluid pressure supply passage 41 from the sub-pump 11 and the return passage 42 to the tank 13. |
