| 摘要 |
PROBLEM TO BE SOLVED: To suppress a flicker without requiring complicated constitution.SOLUTION: A power supply device connects first to third heaters to a common AC power supply source via a plurality of switch elements, and includes a power source circuit switchable to a serial connection of two heaters among three heaters, a parallel connection of three heaters, and/or the connection combining the parallel and serial connections. The power supply device allows the second and third heaters in a serial connection state to start the supply of the power, and allows the first heater in the parallel connection state with the second heater to start the supply of the power while kept in a power supply state, and after an elapse of the predetermined time, the first to third heaters are switched to the parallel connection state, and after that, a duty control is executed for two or less heaters among the first to the third heaters.SELECTED DRAWING: Figure 8 |
