VARIABLE-SPEED DRIVEN TYPE COAL MILL

摘要

PROBLEM TO BE SOLVED: To improve the mill function and suppress the roller wear in a variable-speed driven type coal mill controlling the rotation speed of a mill table to be optimum corresponding to the load quantity and type of coal and controlling the gap between a roller of the mill and the table to be constant. SOLUTION: A table 14 of a mill main body 15 is rotated by a motor 22 through a gear connection apparatus 16. A load instructing signal (the load quantity and the type of coal) 31, a coal layer signal 32 from an angle detector 23 for detecting the angleθof a roller 5, and a rotation speed feedback signal 35 of the motor 22 are transmitted to a control apparatus 20. The data of the optimum rotation speed of the motor 22 corresponding to the load and the type of coal and the optimum angleθare previously stored in the memory part 24 in the control apparatus 20 and those signals are compared with the data in the memory part 24 by a computing part 25 and a frequency instructing signal 33 to give the optimum values to the load and the coal layer and to keep the gap (t) constant is transmitted to an inverter 21. The inverter 22 converts the signal into a rotation speed instructing signal 34 to rotate a motor 22 and drive the table 4 at the rotation speed suitable for the load quantity and the type of coal with which the table is loaded at the time.