Patent GB-1027293-A (GB)
Title: Filter
IPC: B04B1/00
Filed: 1963-05-08
Abstract: 1,027,293. Centrifugal separators; centrifugal strainer separators. H. MULLER. May 8, 1963 [May 19,1962; Jan. 31, 1963], No. 18233/63. Headings B1D and B2P. Material to be centrifuged is introduced at 6, Fig. 5, where the hollow part of the driving shaft communicates with the space between plates 2 and 3. Solids 4 accumulate against a tubular closure member 5, and may be released, into the surrounding trough shown, by the sliding of member 5 to the left over plate 2. Liquid separated by decantation only passes over the edge of a radial circular deflecting disc to apertures 9 and is collected at 10. Liquid passing through an annular portion of filtering fabric 20 emerges at 21 and is also collected at 10. Parts 2, 3 and 5 are all rotated by the shaft. The filtering fabric 20 may be dispensed with, Fib. 1 (not shown). In Fig. 9, (not shown), the shaft supports only parts 2 and 5 directly. Plate 3 is secured by rods to plate 2, and its centre is cut away to provide a feed opening; here, fabric 20 is retained but the deflecting disc and apertures 9 are dispensed with. Lateral displacement of closure member 5 may be effected by a pneumatic diaphragm mechanism rotating with the shaft. The deflecting disc may have, on both faces, paraxial vanes which extend outwards nearly radially, Figs. 2 to 4, (not shown). The filtering fabric 20 may be replaced by several paraxial filter tubes extending between plates 2 and 3 near their periphery, Figs. 6a and 6b, (not shown). Alternatively, it may be replaced by a number of hollow annular filter leaves arranged in planes perpendicular to the axis between plates 2 and 3, Figs. 7 and 8, (not shown). In a modification of Fig. 5, the shaft stops short at plate 2, and plate 3 is open at the centre (as in Fig. 9), but the deflecting disc and apertures 9 are retained, the apertures 9 being joined to apertures 21 by radial pipes, Fig. 11 (not shown). The pneumatic diaphragm mechanism may be dispensed with, and compressed air fed instead directly to the space between plate 2 and closure member 5 to move the latter, return movement being effected by a spring, Fig. 12 (not shown). Closure member 5 may form an extension to a cylinder slidably mounted on the driving shaft, the cylinder cooperating with a radial piston disc also mounted on the driving shaft, the cylinder being fed or evacuated to move member 5, Fig. 13 (not shown). In Fig. 14, not shown, a radial piston disc is arranged between two spaced plates 2, and a closure member 5, secured to the disc periphery, extends in both axial directions. Axially beyond each plate 2 is a plate 3 so as to form two "back-to-back" separators. When the piston disc is forced by compressed air into proximity with one plate 2, the closure member closes the separator on that side and leaves the other separator open, and vice versa. In Fig. 17, (not shown), the filtrate outlet 21 is controlled by a valve; in Fig. 18 (not shown) an automatic baffle device replaces the valve. In Fig. 19 (not shown), deflecting disc apertures 9 and 21, and filtering fabric 20, are all dispersed with; instead, a narrow annular gap is provided between plate 3 and closure member 5, which now surrounds it radially; also, a layer of coarsegrained material is deposited around the inside of member 5, along which layer liquid must flow axially to be filtered before emerging through the annular gap referred to. In Fig. 20 (not shown), perforated rings, steel wool or the like may be inserted between the deflecting disc and plate 2 to reduce turbulence. In Fig. 21, (not shown), an annular collecting channel surrounds the outside of all apertures 9 to promote uniform flow. In certain cases the closure member 5 may be lined with a filtering fabric or screen, from which solid particles are brushed off by plate 2 when member 5 is moved to open the separator.