GB575071A - Granular material grader and purifier - Google Patents

Abstract

575,071. Centrifugal, apparatus. HART-CARTER CO. Feb. 24, 1944, No. 3476. Convention date, Dec. 26, 1942. [Class 23] A granular material classifying machine comprises a rotary, grooved table A, leading to a non-rotary tube B having troughs 35, 35<1> into which'the material is sorted due to the combined action of centrifugal force, and air currents caused by an external fan sucking in air through holes 23 in the casing top. The table A carries sweeps 39 to force the graded material into separate delivery troughs 38. Periodically stiff brushes carried by A, can be rocked over by hand, to sweep the troughs 35, 35<1>. The currents of air, can be regulated by movement of a shield 23<1> having holes to align, or otherwise, with the holes 23. A further regulation comprises a plate 107 which can be turned by rotating a knob 112 to reduce, or increase; the size of the hole 106 leading to the air exhaust 66. A disc 72, for scattering the material admitted through a duct 22a, is fixed to a high speed shaft 64 driven by an external pulley 88, and internal pulleys 95, 96 connected by rope drives. The table A is driven from the same source through pulleys 92, 91 and a slow-speed shaft 34. The belt drives are tensioned by a jockey wheel 81 acted on by a spring 85. Adjustable deflectors 45 sweep material into grooves 28 on either side. The deflection may be angularly adjusted by screw knobs 57 causing movements of slides 50. The position of each slide is shown by a pointer protruding through a slot in a graduated scale S. The air currents pass either downwards or upwards inside a partition 69, through holes 62, and down the inside of a tube 27. Baffles 76 prevent the air from being rotated. The table A and the disc 72 are rotated in the same direction. A cone 67 acts as a material spreader. Windows are provided in the casing 21. Specification 549,019 is referred to.