PURPOSE: To make various controls more exactly by knowing the respective timings for the start and end of raw material falling in accordance with the change signal of the oil pressure in a hydraulic circuit in the stage of charging the raw materials dischaged from a stationary hopper via a swiveling chute into a blast furnace.
CONSTITUTION: The pressure change of the hydraulic circuit for driving a hydraulic motor 11 is detected by a pressure gage 15 with external signal output to detect the swiveling resistance of the swiveling chute 9. The detected resistance is outputted to a raw material falling timing discriminator 16. A calculator 18 calculates the swiveling angle of the swiveling chute 9 in the stage when the falling of the raw materials starts and the angles of swiveling and rotating during the falling of the raw materials from the output signal for the raw material falling timing from the discriminator 16 and the swiveling angle signal from a position detector 17. The swiveling angle of the chute 9 in the succeeding stage for starting the raw material falling is determined by the arithmetic process using the calcualated angles as variables and is outputted to a gate conrol device 19. The gate control device 19 controls the opening action of sealing valves 6, 7 then gates 4, 5.
KIGUCHI MITSURU
SATO KAZUYUKI
Next Patent: DEVICE FOR THROWING CHARGE INTO BLAST FURNACE