Sand filter with concentric filter vessels, has sand suction tube movable along circular groove in base of outer vessel as sand suction part rotates

摘要

The outer vessel (A) is tapered towards its base and a suction tube for the sand can move along a circular groove in the base of this vessel as the sand suction part rotates about the filter central axis. A sand filter comprises at least two concentric, partly cylindrical filter vessels, the inner vessel (B) containing at least one sand suction part. The outer vessel is tapered towards its base and contains a base opening in the form of a circular groove. The movable sand suction part can be rotated about the filter central axis so that a suction tube for the sand can move along the groove as the sand suction part rotates.