| 摘要 |
PROBLEM TO BE SOLVED: To more quickly and accurately detect rapid descent of raw material charged into a blast furnace than before. SOLUTION: When the charge of the raw material 1100 into the blast furnace 1000 is completed, speed control is performed on a motor 400 and a weight 800 is descended from a waiting position. Thereafter, when the weight reaches a lowering speed reducing point, the control of the motor 400 is changed from the speed control to torque control. Consequently, the torque control is performed on the motor 400 in such a manner that torque having a magnitude of a first torque setting value T<SB>1</SB>generates in the motor 400 in a direction of raising a wire 700 wound on a drum 600. Thereafter, when it is determined that the position of the surface 1100a of the raw material 1100 is rapidly descended caused by slippage etc., the torque setting value is changed to a setting value (a third torque setting value T<SB>3</SB>) corresponding to the rapid descent of the position of the surface 1100a of the raw material 1100. COPYRIGHT: (C)2011,JPO&INPIT |
