| 摘要 |
PURPOSE:To enable the efficient operation by a simple constitution by blocking a current to be supplied to a coil for demagnetization or changing the current into a smaller current than that current by detecting the magnitude of the current flowing in the demagnetization coil which changes by separation of an object to be demagnetized from a demagnetizer after completion of a demagnetizing process. CONSTITUTION:When a work is separated away from a demagnetizer 1 gradually, the output of a current detecting coil 13 increases gradually by a change of an inductance of a coil 2 and also a detected voltage Ep1 increases. When the magnitude of the detected voltage Ep1 becomes larger than a reference voltage Eo2, the output S2 of a comparator 22 becomes high level. As a result, a transistor Q3 gets in off-state and a transistor 4 gets in off-state after the constantly continuous time T according to a discharge of a capacitor C4 thereby blocking the energizing of an excitation coil 21z. Then relay swtiches 12x and 12y are changed into the side of b-junction 12bx and 12by so that the supply of the main current I to the coil 2 is prevented and the detecting current Ip is supplied again. Consequently, the output S2 of comparator 22 also moves to a low level. |
