| 摘要 |
PURPOSE: To prevent pressure of a line passage from being lowered without providing any pressurizing means. CONSTITUTION: A back pressure valve 62 is provided on a return passage 42 extending from an oil pressure pump 38 for power steering to a reservoir tank 41, an accumulator 61 is provided on a passage 45 connected to a second return passage 46, flowing of oil is allowed to the return passage 42 side only when the pressure oil from the return passage 45 side becomes the specified value or more, the inside of the second return passage 46 is made into the pressurized state and into a state where pressure oil is accumulated by the accumulator 61 without making the inside of the piping into the always pressurized state. Oil from a check valve 47 is reliably allowed to flow without making the piping into the pressurized state by pressurizing the reservoir tank 41, bubbles in the piping are eliminated, and pressure of a line passage 43 is prevented from being lowered regardless of the rotational state of an oil pressure pump 38 without providing a large-scaled pressurizing means to the reservoir tank 41 or firmly fixing the piping and without affecting an oil pressure system for power steering. |
