Excitation current control device and the excitation current control method of the lifting magnet

摘要

PROBLEM TO BE SOLVED: To provide an exciting current control device for a lifting magnet, capable of carrying out efficient lifting work for safely carrying articles even if they are wide, while preventing the burnout of a coil without increasing the size of the lifting magnet, and to provide its method.;SOLUTION: The control device controls an exciting current I(t) to be supplied to the lifting magnet M. It comprises a normal mode processing part 11 for setting the exciting current I(t) to be a normal value lower than a mode threshold value, a ferromagnetic force mode processing part 12 for setting the exciting current I(t) to be higher than the mode threshold value, a remaining operation amount calculating part 22 for calculating a remaining operation amount F for operating the ferromagnetic force mode processing part 12, and a ferromagnetic force mode restriction processing part 23 for restricting an operation amount for operating the ferromagnetic force mode processing part 12 corresponding to the remaining operation amount F calculated by the remaining operation amount calculating part 22.;COPYRIGHT: (C)2005,JPO&NCIPI