GB1080108A - Improvements relating to roller mills - Google Patents

Abstract

1,080,108. Automatic level control. GEBRUDER BUHLER. Nov. 4, 1965, No. 46800/65. Heading G3R. [Also in Divisions B2 and G1J Operation of a roller mill is controlled in accordance with variations in the quantity of material fed to the mill, measured capacitively. Material entering through shute 4 passes between feedroller 5 and flap 6 and then between fixed roll 2 and adjustable roll 3. Material piled above feedroller 5 determines the capacitance between plate 33 and housing 1, the value of this capacitance being displayed at 45 to indicate the throughput. This signal is modified by adjusting elements 83, 97 and 93 and the resulting signals control solenoids 63, 77 and 73. Solenoid 63 controls the position of flap 6 to vary the feed of material, solenoid 77 controls the spacing of rolls 2, 3 and solenoid 73 separates the rolls when the flow of material ceases. Instead of, or in addition to, controlling flap 6 the signal may be used to control the speed of a motor driving roller 5. The supply of coolant to rolls 2, 3 may also be controlled. Plate 33 may extend the whole length of roller 5 or merely the width of shute 4. Additional detecting elements may also be provided. A doubleroller mill is referred to, having two pairs of rolls fed from a single shute. In this case a single live plate is disposed between two earthed plates and operation of the feedrollers and rolls in the two mills is controlled in accordance with the feed through the corresponding channel.