GB1018564A - Improvements in or relating to control devices for hoppers - Google Patents

Abstract

1,018,564. Roller mills. G. BUHLER. Jan. 14, 1964, No. 1610/64. Heading B2A. [Also in Division B8] Material which is fed from a hopper by roller 13 past gate 14 so that it may be ground by rollers 11 and 12 has the gap which lies between roller 13 and gate 14 controlled in size by detector 15 so that whenever the material in the hopper increases in quantity the said gap is increased to increase the feed to the rollers 11, 12. A detector 100 which floats to the surface of the material in the hopper has a propeller 29 which is driven from roller 12 via belt 21 and shaft 25. Arm 17 which carries propeller 29 surrounds shaft 25 and is pivoted at 16 and counter-balanced at 30 so that the up and down movement of the propeller 29 may be transmitted to gate 14 via levers 33, 34, bell-crank 36, arms 39 and 41 and rod 44, the gate 14 being pivoted to turn about shaft 45. Operation. If the material in the hopper (not shown) increases propeller 29 swims to the surface thereof. Additionally propeller 29 drives agitator 80 to spread the material in the hopper. The rise of propeller 29 is transmitted by the linkage shown to gate 14 so that the latter pivots to widen the gap between roller 13 and itself. Also the movement of bell-crank 36 operates switch 50 whenever the propeller 29 falls to a predetermined lower limit. This switches off the motors which drive rollers 11 and 12 or widens the gap therebetween. Alternatively the control between propeller 29 and the rollers 11, 12 may be hydraulic and replace switch 50.