Patent GB-222185-A (GB)
Title: Process and apparatus for separating intermixed divided materials of different specific gravities
IPC: B03B4/02
Filed: 1923-06-21
Abstract: 222,185. Peale, R., Peale, R., and Peale, R. June 21, 1923. Separating by shaking-apparatus; pneumatic separating.-In a process for separating intermixed divided materials of different specific gravities the materials on a pervious table are stratified by air forced under pressure through them and by the jigging movements imparted to the table which cause the lower and upper strata to move longitudinally in opposite directions. In the construction shown in Fig. 1 the inclined table 1 forms the top of a compressed air chamber 4 and is pervious to air, the air holes being disposed so as to provide a decreasing pressure towards the lower end. The varying air pressure may be obtained by shrouding a uniformly pervious table to an increasing degree in the lower zones. Transverse ridges 15 inclined upwardly are provided to assist the travel of the lower stratum, or the table may be corrugated. Longitudinal boards 90 divide the table into a number of separate channels, and the sides are formed of high boards 111. Two adjustable plates 110, 121 cover the top to prevent dispersion of dust and also to direct the air downwardly and rearwardly and assist the discharge of the upper stratum of material. The materials are fed from a hopper 125 either bv gravity or a valve device. Blocks 91 with bevel ends 91<a> are positioned beneath the ends of the boards 90 and define passages for the delivery of the heavy material. An adjustable back plate comprising a horizontal board 96 and vertical board 97 closes the top of the passages and acts as a baffle for the lighter material and a deflector for the air. A hinged and weighted door 150 allows delivery of the heavv material under a predetermined pressure. The movable, frame 34 carrying the table and air chamber is supported by links or rollers on the fixed adjustable frame 18 and is actuated by a cam 70, as shown, and springs so as to have a slow backward movement and a rapid forward movement which is suddenly arrested by the contact of abutments 84, 85. The air supply may be controlled by suitable slide valves at the inlet to the fan or in the supply pipe. In a modification, Fig. 14, the upper side of the table is covered by a large expansion chamber 214 in which the dust carried off by the air is deposited and from which it is drawn off by a shoot 225. The hopper 125 is supplied by a large hopper 195 from which the material is fed by a reciprocating plate 198 through an aperture controlled by a slide 209. The. support of the table consists of rocking arms 188 lying in sockets 187, 189. The top end of the frame is connected by slides 190 and compression springs 192 to the fixed frame and is actuated by a cam. The fixed frame is pivoted centrally and adjusted by supports 25 at each end. In the modification shown in Fig. 15 the air is drawn through the table by the suction of a fan 279 exhausting the space formed by a casing 250. The ton of the casing has a part 266 the height and inclination of which is adjusted to regulate the air currents. The fine dust carried off by the air is deposited in the expansion chamber 287. The fixed frame is pivoted at its forward end and adjusted at its rear end by a jack 238. The table is supported by links 36, and actuated by a cam 70 and springs, the impact abutments 84, 85 being relatively adjustable by a transversely sliding bar 240 with inclined surfaces engaging the abutments 85.