Patent ID: 7832422

Claim:
A valve comprising: a valve element; a valve seat; a coil spring; and a spring bearing portion, wherein the coil spring, provided between the valve element and the spring bearing portion, presses the valve element toward the valve seat, wherein the coil spring has an effective winding region that bends when an axial load is applied to the coil spring, the effective winding region being between an effective upper winding end, which is a point in an upper portion of the coil spring at which an axial direction rigidity of the upper portion of the coil spring is largest, and an effective lower winding end, which is a point in a lower portion of the coil spring at which the axial direction rigidity of the lower portion of the coil spring is largest, and the effective upper winding end of the coil spring, and the effective lower winding end of the coil spring being offset from each other by 180 degrees in a plan view.