| 摘要 |
PROBLEM TO BE SOLVED: To obtain a relief valve capable of controlling a relief flow rate at a low oil temperature and at a high oil temperature of relief oil.SOLUTION: A relief valve comprises: a valve element A composed of a valve housing 1 having a hollow chamber 14 in which the back end of only the axis direction is opened so as to form an inflow opening 14a, and a relief hole 15 making the inner circumference communicate with the outer circumference of the hollow chamber 14 in a diameter direction, and a flow rate changing means 2 which changes the flow rate of the hollow chamber 14; a valve passage 4 in which the valve element A is arranged, and having a relief inflow portion 43 at the back end side of the axial direction, and having a first relief port 41 in a position separated along the moving direction of the valve element A rather than the position of the relief hole 15 of the valve element A in an initial halt state from the back end side, and having a second relief port 42 positioned at the back end side relative to the relief hole 15; and a spring 5 which presses the valve element A to the relief inflow portion 43 side of the valve passage 4. The flow rate changing means 2 is arranged in the hollow chamber 14, and controls the flow rate so as to be reduced at a high oil temperature, and increased at a low oil temperature. |
