| 摘要 |
PURPOSE:To prevent the reverse flow of water from a downstream side by closing an overflow hole with a diaphragm valve by the pressing force of the water being poured in a hot water feeder and by a suction force due to negative pressure. CONSTITUTION:When water is being poured in a hot water supplying device from upstream water feed passages U1 and U2, the water is received in a receiving container part 10 and thereafter part of the water enters a pressure application chamber 60 to press a diaphragm value 50 normally spring-biased to be under an open condition to an overflow hole against the force of a spring 51. On the other hand, since a major part of the water passes through an inner cylinderical body 30 as a primary passage, a space S between the inner cylindrical body 30 and an outer cylindrical body 20 becomes a secondary passage which, during water pouring, is made negative in pressure due to the ejector effect resulting from the overflowing from the primary passage. Therefore, the diaphragm value 50 held against the overflow hole 21 from outside is further held thereon by the negative pressure from inside to completely seal the overflow hole 21. In this way this method can prevent the water from reverse flow from the downstream side. |
