| 摘要 |
<p>A back-flow preventer for household appliances, e.g. washing machines which are connected to the water main, has a section of the inlet conduit open to the atmos, inside a ventilated housing. The water flows from a converging, slit-like jet, around a curved guide surface which is tangential to, and contiguous with, one side of the feed jet, the inner side of the curved path being open to the atmos, and then into a divergent intake jet which is similarly tangential to the curved surface, and symmetrically oriented wrt the feed jet. The device is simple to construct but effective and reliable, giving negligible leakage even with low supply pressures.</p> |
