| 摘要 |
Liquid filter, in particular for purifying sea water or river water, has one or more screen tubes (11, 11', ...), into which the liquid to be filtered is introduced at one end and which retain impurities, but which allow the purified liquid to pass through the perforations. For cleaning the screen tubes (11, 11', ...), in whose perforations thread-like foreign bodies can be attached, a reduced pressure, distributed over the active surface of the screen tubes is produced with the aid of a cleaning valve (12, 12', ...) of a suitable shape and size at the other end of each screen tube (11, 11', ...). The valve (12, 12', ...), preferably a pinch valve, has a passage cross-section which permits the screen tube (11, 11', ...) to empty in a short time and without the occurrence of blockages. During the operation of the filter, the valves (12, 12', ...) can be opened in a predetermined sequence, optionally controlled by the pressure in one or more of the screen tubes (11, 11', ...). <IMAGE> |
