| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a pressure relief valve of high long-term reliability capable of preventing shortening of service life caused by corrosion and damage of a tip side of a valve seat having a valve hole. <P>SOLUTION: This pressure relief valve is provided with a pressure input passage 3 and a pressure relief passage 4 in a valve main body 2. The valve seat 5 is mounted at an outlet side of the pressure inlet passage 3, the pressure input passage 3 and the pressure relief passage 4 are communicated through the valve hole 6 of the valve seat 5, and a valve portion 7 is energized to a valve seat 5 side by an energizing spring 18 to apply the energizing force in the valve closing direction. When a pressure of the pressure input passage 3 is lower than a set pressure, the valve portion 7 is brought into contact with the valve seat 5 by the energizing force of the energizing spring 18 and valve closing motion for closing an inlet end of the valve hole 6 is performed, and when the pressure of the pressure input passage 3 is higher than the set pressure, the valve portion 7 is separated from the valve seat 5 against the energizing force of the energizing spring 18, and valve opening motion for opening the valve hole 6 is performed. The valve seat 5 is formed by concentrically circularly arranging a plurality of circular projecting portions 8 projecting to a valve portion 7 side at intervals in a state of surrounding the valve hole 6. <P>COPYRIGHT: (C)2007,JPO&INPIT |
