| 摘要 |
PROBLEM TO BE SOLVED: To provide a check valve in which a back flow does not occur even when a large shock wave generates when a hot water/water mixing faucet is suddenly switched from an open state to a closed state, in the check vale used for a hot water/water mixing faucet and the like.SOLUTION: At an end surface of a body 3 facing a downstream side, a cylindrical wall surface 3f is formed extending toward an upstream side from an inner periphery of a valve seat 3e. At a surface of a contact member 6 facing the upstream side, a valve part 6a seated in the valve seat 3e is formed, and also, an annular groove 6c coming into contact with the inner periphery of the valve part 6a is formed. On a side surface on the inside of the annular groove 6c, a contact wall surface 6d is formed in an annular manner. The contact wall surface 6d is formed in a taper shape so that a diameter reduces toward the upstream side. A diameter of the contact wall surface 6d is set to be the same as a diameter of the cylindrical wall surface 3f in an intermediate part in the upstream and downstream directions, so that, when a pressure to the upstream side acts on a valve body 5 by a shock wave, a portion on the downstream side from the intermediate part of the contact wall surface 6d comes into press contact with the cylindrical wall surface 3f. |
