| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To surely prevent reverse inflow from a storage tank side even in an abnormal operation. <P>SOLUTION: A hot water filling solenoid valve 53, an edge cutting valve set 7 and check valves 54, 55 are mounted in a hot water filling channel 50 branching from a hot water supply circuit for filling hot water in bathtub. The hot water filling solenoid valve is opened during filling the hot water to thrust a subsidiary selector valve 71 with water supply pressure and move down the subsidiary selector valve and an air charge valve 72 integrated with a valve shaft 711 against a spring 715. The lower movement causes the opening of the subsidiary selector valve, the closing of the air charge valve and the opening of the check valves to fill the hot water. Upon completing the filling of the hot water, the check valves are closed by closing the hot water filling solenoid valve and then remaining water supply pressure in a valve chamber 741 is opened by opening a pressure release valve 73, whereby the subsidiary solenoid valve is closed and the air charge valve is opened to be reset to a steady state. In a steady state, even when the hot water filling solenoid valve fails in closing operation, air is momentarily sucked therein to avoid negative pressure because of the air charge valve being always opened, if negative pressure is produced in the hot water supply circuit, resulting in no occurrence of a counter flow. <P>COPYRIGHT: (C)2003,JPO</p> |
