摘要 |
<p>A flow control valve having a seating surface formed on a valve element to contact a valve seat when the valve is closed has a shape of a part of a hypothetical spherical surface having a spherical center at a center of a supporting member. Therefore, the distance from the center of the supporting member to the seating surface is kept constant, and the valve element can be seated at a periphery of the valve seat without a gap, even if the shaft is inclined. Thus, the valve leakage is reduced. The supporting member supports a shaft connected to the valve element movable in an axial direction of the shaft. The center of the supporting member is aligned with a center of the valve seat. Movement of the supporting member in a radial direction of the supporting member is prohibited. Therefore, the center of the supporting member is not displaced from the center of the valve seat in the radial direction. Accordingly, the displacement of the shaft in the radial direction can be prevented. Therefore, the valve element is certainly seated on the valve seat, and the valve leakage is prevented.</p> |