GB851851A - Improvements in or relating to rotary filters - Google Patents

Abstract

851,851. Rotary filters. KEENE, E. W. W. Jan. 9, 1957 [Oct. 10, 1955], No. 28735/55. Class 46. The rotor of a rotary filter comprises a rotatable shaft 9, Fig. 2, having centrally mounted thereon a support 14, 15, Fig. 1, carrying filter leaves 22, 23, which overhang the support symmetrically, Fig. 2, to form inner and outer drums with open ends to accommodate scrapers for the filter leaves, (though one drum only need be provided). The support consists of arms 14 tangential to the shaft 9, adjacent arms being crossed, lattice fashion, by shorter arms 15, and the whole being braced by arms 16, 17 mounted on brackets 18, 19 (a, b) respectively on the shaft and secured to the meeting points of the arms 14, 15. These arms support brackets 20, 21, of angle section which carry the overhanging filter leaves 22, 23. Each filter leaf consists of parallel perforated plates 40 spaced apart by V-section struts 36, Fig. 3, and each covered with filter cloth 52 clamped at the inner edge between plates 41, 42. The cloths are also held close to the screens by wire clamps 53, Fig. 6. Rods 47, accommodated between recessed ends 38 of adjacent leaves, retain the filter leaves in their proper relative positions. A tubular stud 45 in each leaf connects the interior of the leaf to a vacuum pipe 33a, communicating with an annular vacuum chamber 34 Figs. 1 and 2, the vacuum drawing liquid from a tank 24, into which the filter dips, into the interior of the leaves. Scrapers 25 ... 28 contact the filter cloths to remove residue which is directed by a guide plate 29 and shoots 30 ... 32 away from the filter. As shown in Fig. 6, a wire scraper 25 is yieldingly pressed against the filter cloth by a counterweight 50 and is guided by a prong 54 having a curved end over the junctions between adjacent filter leaves. Material removed by the scrapers may be broken up by a beater 64 actuated by an eccentric 58, and may be discharged by a screw conveyer 56 instead of a shoot. Alternatively a belt conveyer may be used. The scraper may be replaced by a roller. A quick-release clamping device for the outer edge of a leaf is depicted in Figs. 8-10 (not shown). The rods 47 may be replaced by sealing members for the cloth edges. The raw liquid may be stirred by agitators 66 ... 68, Figs. 1 and 2. The provisional Specification describes and shows inner and outer scrapers guided from one filter leaf to the next by cam washers on the rods 47, the screw conveyer 56 being replaced by a tipping hopper. Specification 519,689 is referred to in the Provisional Specification.