| 摘要 |
PROBLEM TO BE SOLVED: To provide a self-exciting inverter device at a low cost for conducting a frequency control for preheating and starting a discharge lamp, and an operation frequency control corresponding to load current fluctuation. SOLUTION: A self-exciting inverter circuit is provided with a drive circuit driven by using a current transistor 8' input with the load current of the transistor 3 being an output switching element of a high frequency conversion means. Therein, since the driving circuit of the transistor 3 has a thermistor 13, a temperature depending variable resistant element, the resistant value of the thermistor 13 changes by temperature change resulting from the increasing and decreasing of self generation or the fluctuation of an ambient temperature so that the current and the phase of a secondary winding changes comparing with the current (the load current) phase of the primary winding side of the current transformer 8'. Therefore, the timing of the transistor 3 changes so that the operation frequency of the inverter device can be changed without any special control circuit. |
