GB700404A - Improved feeder for granular bulk material - Google Patents

Abstract

700,404. Screw conveyers. BUHLER, GEB July 3, 1950 [July 21, 1949], No. 16575/50 Class 78 (1). A feeder for granular material comprises a hopper 1, a downwardly-opening worm trough 2 disposed in the hopper, a distributing worm 5 and a feeding worm 10 journaled in the hopper in parallel relationship, the worm 5 having a greate pitch than the worm 10 and moving the materia partly from the middle of the hopper outwardly whereas the worm 10 moves the material axially from the ends of the hopper inwardly, and gate 14 pivoted in the hopper above the worm and adjustable in a direction at right angles to them for controlling the flow of material. The helices of the worms are of opposite hand and the helices 6, 7 of the worm 5 are mutilated. The ends of the worm 5 are provided with blades 8, 9 each of which forms part of a helix of opposite hand to the adjacent helix. The gate 14 has a slide 19 mounted on it which carries a rack 18. A toothed sector 17 pivoted at 29 in the gate engages the rack and is turned by rotating the screw 16. This screw engages a member 30 rotatably mounted in the sector and its end is connected to a member 32 rotatably mounted in the gate. The trough 2 may be adjustable vertically. The worm 10 is driven at constant speed from a pulley 23 through reduction gearing 24 and is coupled to the worm 5 through gears 25, 26 designed to enable the latter to be driven at a maximum speed equal to half the speed of the worm 10.