GB740126A - Improved apparatus for use in classifying or both classifying and drying loose material - Google Patents

Abstract

740,126. Sifting-apparatus. TOPP, H. J. B. April 21, 1954, No. 11566/54. Class 117. Material to be classified is fed from a hopper 10, Fig. 1 onto a rotating disc 14 from the edge of which it spills onto a rotating screen 22. A fixed spider 11 supports a cage 15, comprising rings 13, over the disc and may also carry baffles 25, 26, Fig. 2, to facilitate the movement of material on the edge of the disc 14. The disc 14 is carried by arms 16 from a container 18 which carries the screen 22. Conduits 20, 24 receive the classified material, and radial blades 23, Fig. 3, rotating with the container 18 and screen 22 urge the fines into the conduit 24. The inner surface of the screen may have ribs. A drying wind may be injected at 24 to issue at 5. In the modification of Fig. 5, the rotating screen 48 is inverted and the classified materials are taken from ducts 45, 46. A brush 51 bears on the screen for cleaning, and the pressure exerted by the brush may be adjustable, e.g. as by a counterweight. The brush may be rotated about its axis by an electric motor, Fig. 9 (not shown). Several such brushes may be used. In Fig. 10, the shaft 36 carrying the screen and disc is supported in a bearing 63 which is resiliently supported from a base-plate 29. The screen-disc assembly may additionally be supported against lateral displacement as shown in Fig. 11; a spider 68 extending from the disc carries rollers 69 which run on a rim 70 of the stationary casing. To allow adjustment of the vertical position of the rotating disc and screen, each roller 69, Fig. 13, may have a bearing 72 eccentrically mounted on the spider, so that by loosening nut 73a the bearing may be rotated to raise or lower roller 69. In Fig. 15, the casing 30 rotates with the screen 48, a rim 74 bearing on fixed rollers 75. By corrugating the under surface of rim 74, Fig. 15, or the rim 70, Fig. 11, the screen may be given a vibrating movement while rotating. The lower portion of the feed tube 33, Fig, 5, 11 may have an adjustable skirt 78, Fig. 6, to vary the gap between the feed tube and the rotating disc 35. A plurality of screens, each feeding a different channel, may be employed.