CONTROL METHOD AND DEVICE OF COIL LIFTER FOR CRANE

PROBLEM TO BE SOLVED: To reduce the arm moving time by hanging up a coil by an arm in the condition controlling each coil to make the mutual interval between a pair of claws into a preset value larger than the width of the coil in the axial direction. SOLUTION: The arm interval detecting means 16 of a control device 12 detects the arm interval of a coil lifter and outputs it to a control means 19, an instruction means 17 outputs the coil width to the control means 19, and the control means 19 operates the object value of the arm interval at each coil, depending on the output of the instruction means 17, the winding slippage amount of the coil in the width direction, and the stopping accuracy of a crane found beforehand, and controls to make the detecting value of the arm interval to the found object value. Since the arm interval is controlled to be made to an adequate object value according to the width of the coil, the arm moving time can be reduced compared in case of releasing until the full opening constantly. Since the control of the arm interval is carried out simultaneously in the moving condition of the crane, the working time of one cycle of the crane can be reduced.