| 摘要 |
<p>The present invention relates to water purification devices, particularly to gravity- fed water purification devices that operate without electricity and pressurised water. The invention relates to a gravity- fed water purification device comprising a chamber (3) that has the sediment filter (6), also has a compartment (7) that surrounds the sediment filter (6). The compartment (7) has sidewalls (16) rising upwardly from bottom of the chamber (3) to define an open top with a rim having a notch (7a). The compartment (7) is spaced apart from the walls of the chamber (3) to define a space around the compartment (7). Preferred devices were surprisingly found to solve the problem of tapering -off of the flow- rate from the device over a period of use, and the need to frequently back wash the carbon block filter (9), particularly under conditions of poor water quality and at the same time provide the required residence time for the chemical purifying agent to act on the pathogens.</p> |
