主权项 |
1. A flow control valve comprising:
a valve housing defining a valve chamber internally and having an inlet port and an outlet port, the inlet port and the outlet port being opposed to each other in an axial center direction of the valve chamber and opened to the valve chamber; a valve element equipped in the valve chamber and movable between an OFF position, which is on a side of the inlet port, and an ON position, which is on a side of the outlet port; and a spring configured to bias the valve element toward the OFF position, wherein the valve element is configured, on receiving pressure of fluid flowing into the inlet port, to move from the OFF position to the ON position to switch a flow quantity of fluid, which flows through the valve chamber, from a large flow quantity to a small flow quantity, the valve element is further configured, on decrease in pressure of fluid flowing in the inlet port, to return from the ON position to the OFF position to switch the flow quantity from the small flow quantity to the large flow quantity, the valve chamber has a fluid passage including an outer passage to flow fluid therethrough, the outer passage being defined between an inner periphery of the valve chamber and an outer periphery of the valve element, the valve chamber has a throttle shape
to decrease in an inner diameter gradually from an upstream end of the outer passage toward a downstream end of the outer passageto decrease a minimum passage area of the fluid passage in a non-linear form andto increase a front-rear differential pressure of the valve element in a linear form relative to a stroke of the valve element when the valve element moves from the OFF position toward the ON position. |