GB1480688A - Transportable screening and grading appliances - Google Patents

Abstract

1480688 Screening apparatus MACHINES & STRUCTURES Ltd 14 Nov 1975 [47138/75 Heading B2H Transportable screening and grading apparatus comprises a wheeled framework 1, a hopper 4 disposed to deliver material to be screened onto the lower end of an inclined main conveyor 5, an elevated screen arrangement 15 receiving material from the top of the conveyor, and a plurality of discharge chutes 7, 8, 9, 10 for the screened material, each discharging onto the lower end of a respective inclined auxiliary conveyor 11, 12, 13, 14, each auxiliary conveyor being pivotable at its lower end about vertical arms laterally spaced from the axis of the main conveyor, whereby it can be nested alongside the main conveyor for storage or transport, or swung out so that the graded material can be discharged into well separated heaps. In the Figs., each auxiliary conveyor is mounted on pivot 21 and supported by stay 22 on pivot 23. The two auxiliary conveyors on one side nest one above the other, the stay 22 of the lower conveyor being kinked as in Fig. 2 to permit storage or supports 25 without exerting on the conveyor a force which tends to pivot it. The apparatus includes a towing hitch 26 and feet or jacks 27. The screening apparatus includes three screens of successively finer mesh (not shown) in frame 15 resiliently supported on sub-frame 6 and suitably vibrated. Washing water is fed onto the material on the screens, and a dewatering screen is located in a frame 18 resiliently supported on a sub-frame 19, and vibrated by a linear vibrator having a line of action at an angle of 45‹ to the horizontal so that material passes up the screen. The angles of inclination of the screens are adjustable by variable length stays 17, 20.