GB1453183A - Separating devices - Google Patents

Abstract

1453183 Separating solid materials A W B DAVIES 8 Feb 1974 [9 Nov 1972] 21497/72 Heading B2H In a method of separating a first material, e.g. stones and clod ,from a second material, e.g. potatoes, having a greater tendency to roll than the first material, the materials are discharged from a first conveyor 4, Fig. 1, onto a second conveyor 12 travelling slower than the first conveyor so as to cause the second material to roll faster than the first material and the materials are discharged from the second conveyor 12 onto a third conveyor 14 travelling in a direction generally counter to that in which the first conveyor 4 travels, the first material being discharged from one end of the third conveyor and the second material being discharged from another end of the third conveyor. Potatoes, stones and clod collected by a harvester may be delivered by an elevator onto a conveyor belt 1 by means of which they are deposited onto a conveyor belt 2 which in turn feeds them transversely across a conveyor belt 4. Due to the greater rolling motion imparted to the potatoes on conveyor belt 2 they are carried across to the side 6 of the conveyor belt 4, while the more irregularly shaped stones and clod with lesser tendency to roll drop from the conveyor belt 2 onto the nearest side 8 of the conveyor belt 4. The latter delivers the potatoes, stones and clod onto a conveyor belt 12 which travels at a slower speed than the belt 4 so that the potatoes, which roll faster than the stones and clod, fall onto and roll along a contramoving conveyor belt 14 from one end of which they are discharged onto a conveyor belt 16. The stones and clod rolling more slowly than the potatoes are carried by the belt 14 and delivered at its opposite end onto a conveyor belt 22. A deflector plate 20 may be provided to ensure that the stones and clod are directed onto the belt 22. In a modification, the belt 12 may travel in the same direction as the belt 14. In a further modification, Fig. 7 (not shown), the belt 4 may carry slots (28) which project from its surface and which extend partially or wholly across the belt. The outer surfaces of any of the conveyor belts may be smooth or, as shown in Fig. 6, may be provided with resilient rubber or plastics projections which may be located over the entire outer surface of the belt or over only part (e.g. belt 4 in Fig. 1) of the outer surface. The belts 4 and 12 may have a graded profile of projections 10, Fig. 4. The belts 4, 12 and 14 may be adjustable with respect to the horizontal in both the longitudinal and transverse directions.