| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a rush current preventing device for preventing a rush current and a flicker phenomenon caused in controlling the temperature of a heater, particularly, a rush current preventing device for performing an optimum rush current prevention to suppress the generation of harmonic waves (generation of the flicker phenomenon). <P>SOLUTION: In a heater temperature control circuit for heating a heater 11 by the power of an AC power source 10, the current carried to the circuit is detected by a current detector 13, a control signal is outputted from the terminal B of a control circuit 16, and a switching element 12 is set ON/OFF to keep the heater 11 at a saturated temperature (set temperature). The control circuit 16 outputs a control signal from a terminal A according to the current value to ON/OFF-control a switching element 18. In the supply of a current to the heater 11, for example, the switching element 18 is set OFF, a triac 19 is set OFF, and the current is carried to a resistor 5 to prevent the generation of a rush current. After the current is carried to a resistor R5 for the time according to the current value, the triac 19 is set ON to directly supply the current to the heater 11. According to such a structure, the rush current can be prevented, and the power consumption by the resistor R5 can be also reduced. <P>COPYRIGHT: (C)2003,JPO |
