GB772354A - Improvements in filters for removing fine particles from liquids - Google Patents

Abstract

772,354. Filters. AUTO-KLEAN STRAINERS, Ltd. Aug. 11, 1952 [Aug. 10, 1951], No. 18902/51. Class 46. A filter cartridge comprises a tubular former 2 supporting an inner filtering element 6 consisting of a rigid element or elements providing a plurality of accurately dimensioned small slots or apertures, and an outer filtering element 14 consisting of a plurality of turns of a sheet of fibrous material formed into a sleeve by attaching the outer turn securely to the underlying turn or turns. The inner element may comprise a wire 6 closely wound in grooves in longitudinal ribs 4, Fig. 1 (not shown) of the former 2, the spaces between adjacent convolutions define the filtering apertures. Alternatively the inner element may comprise wire gauze or a plurality of closely spaced rings or annular discs. The fibrous sheet 14 may be a felt cloth or a filter paper of which three layers are provided with the starting edge stitched to the overlying layer at 15, Fig. 2 (not shown) and the finishing edge stitched to the underlying layer at 16, Fig. 3 (not shown) ; the two lines of stitching are out of alignment. Wire bindings 19, 20 or spring circlips secure the sheet 14 into grooves 17, 18 of end pieces 7, 11 secured to the perforated former 2. The cartridge is detachably mounted in a liquid filter unit comprising a housing 10 with a detachable end plate 25 and inlet and outlet connections 21, 22 respectively for the liquid.