| 摘要 |
There is shown apparatus 1 for obviating back flow of water through a plug hole 2 (figure 1) of an installation such as a bath, sink or shower, comprising a chamber 3 for receiving water through an inlet 4 and means 5 adjacent the inlet 4 adapted to mount the chamber 3 at the plug hole 2.The chamber 3 is generally cylindrical and the inlet 4 is at the lower end of a tube 4' which is also generally cylindrical and mounted in the embodiment concentrically with the chamber 3 mounted using an adhesive . The tube 4' forms an orifice 6 through a boundary wall thereof through which back water can flow back into a plumbing system when back flow ceases. |
