US Patent 9091352 Flow path opening/closing valve

A flow path opening/closing valve is equipped with a main body having a valve chamber housing therein a rotatable valve body, and a sleeve that abuts without gaps against an inner circumferential surface of the valve chamber, such that the inner circumferential surface of the valve chamber and an inner circumferential surface of the sleeve slide without gaps against an outer circumferential surface of the valve body, for thereby shielding the valve chamber by the valve body and the sleeve. First and second seat members, and first and second o-rings that urge the first and second seat members toward the side of the valve body are arranged inside first and second annular grooves, which are provided on the inner circumferential surface and the inner circumferential surface.