To provide a check valve and a hot water storage type water heater including the same, which suppress noise when a water hammer is performed and an abnormal pressure rise on a secondary side, in an inexpensive and simple structure.
The check valve 11 includes a valve element 15 displaced in an open position and a close position in response to the difference between a pressure of a primary side and a pressure of a secondary side, a guide member 14 guiding the movement of the valve element 15, and an energizing means (a spring 17) for energizing the valve element 15 in a direction of the close position. A guide shaft 15b is provided on either the valve element 15 or the guide member 14, and the guide shaft 15b is inserted into a guide hole 14b provided in the other. A spiral groove 15g comprising a spiral shape is formed on either the outer periphery of the guide shaft 15b or the inner periphery of the guide hole 14b, and a protrusion 14b formed on the other is inserted into the spiral groove 15g. When the valve element 15 is displaced between the open position and the close position, the relative movement of a protrusion 14d in a longitudinal direction of the spiral groove 15g automatically rotates the valve element 15.
SAKUMA TOSHIYUKI
FURUKAWA YOSHIHIRO
AKAISHI TAKAAKI
TERASHI KENTARO
Hideki Takahashi