Patent ID: 8104742

Claim:
A flow control valve comprising; a first port; a second port; a valve seat provided between the first port and the second port; a valve element body movable into or out of contact with the valve seat; an operation member coupled to the valve element body; a cover in which the operation member is movably inserted; a differential screw to adjust a position of the operation member to adjust a position of the valve element body; and a rotation member mounted in the cover to be slidable along a moving direction of the operation member, the rotation member being adapted to apply a rotation force to the differential screw, wherein: the rotation member is provided with a locking portion to prevent the rotation member from rotating when the rotation member is slid, along the moving direction of the operation member, the operation member comprises: a stroke adjustment rod inserted in the cover; and a movable member which is coupled to the valve element body and which is allowed to move inside the cover but prevented from rotating, the cover is formed with an open end in which the stroke adjustment rod is inserted and is provided with a cylindrical holding member around the open end in which the rotation member is fitted, the differential screw includes a first thread portion which engages the stroke adjustment rod with the cover and a second thread portion which engages the stroke adjustment rod with the movable member, and a projected area of the rotation member is smaller than a projected area of the cover.