| 摘要 |
A container (10) for water comprising: a container housing (11) for holding water, the housing having a base, side walls and a top wall; a water filter (19) comprising one or more membranes (22) which are effective to pass water in preference to air under the influence of a pressure differential; an output valve (20) coupled to the water filter (19); and, a pump (18) for establishing a pressure differential across the walls of the container housing, wherein the container housing comprises a main volume (MV) within which the water filter (19) extends and a header volume (HV) above the water filter. For a given internal capacity of a water container of the present invention, the provision of a header volume ensures that the surface area of the water filter in contact with water in the main volume is constant so long as there is water within the header volume. This keeps the membranes of the water filter working at maximum efficiency for longer than they would otherwise. In a preferred embodiment, the container has a capacity of between 1 and 6 litres, more preferably between and 6 litres. Preferably, the ratio of the header volume to the main volume is at least 1:6, more preferably at least 1:5. |
