| 摘要 |
PROBLEM TO BE SOLVED: To provide a degmagnetizing current control circuit which narrows the variation width of a current flowing in a demagnetizer circuit to avoid deteriorating the demagnetizing effect even for a large input AC voltage width. SOLUTION: After a charging time (corresponding to a required decision time of an AC voltage decision circuit 3) with resistors R6, R7 and a capacitor C2 in a second OFF circuit 2, a transistor Q2 turns on to form a conduction state of a demagnetizer circuit ON/OFF relay RL2, thereby turning on a demagnetizer circuit. When a DC voltage applied to a Zener diode D2 exceeds a Zener potential in the AC voltage decision circuit 3, a transistor Q1 turns off to form a conduction state of a resistor short-circuiting AC relay RL1, thereby forming an intermediate state of a demagnetizing current limiting resistor R9. If not exceeding the Zener potential, a short-circuit state of the resistor R9 is formed. COPYRIGHT: (C)2004,JPO
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