| 摘要 |
PROBLEM TO BE SOLVED: To provide a power boosting switching valve that can be put in stable power boosting action with simple structure. SOLUTION: An operating member 26 slid in a parallel direction to a valve stem 22 is provided separately from the valve stem 22 slidably supported on a housing 21 so as to move a valve element in the direction of approaching/ separating from a valve seat. Valve stem roller members 23 with shafts orthogonal to the sliding direction of the valve stem 22 without intersecting are supported to the valve stem 22. Floating roller members 25 are inserted between the valve stem roller members 23 and a tapered face part 27a provided at the valve stem 22 side end part of the operating member 26, so as to come in contact with both the valve stem roller members 23 and tapered face part 27a. The operating member 26 moves the taper of the tapered face part 27a, the floating roller members 25 and valve stem roller members 23 onto the valve stem 22 side, and when the valve stem 22 moves to the valve seat side through the tapered face part 27a, floating roller members 25 and valve stem roller members 23, it is so set and arranged that the valve stem 22 moves by smaller moving quantity than the unit moving quantity in relation to the unit moving quantity of the operating member 26. |
