Image forming apparatus controlling power from a commercial AC power supply to a heater and detecting current flowing in a power supply path from the commercial AC power supply to the heater

摘要

Part of a plurality of power levels of control patterns selected to control power supplied from an AC power source to a heater of an image forming apparatus include power levels of a) waveforms in which power is supplied in part of negative and positive half cycles in order after no power supply during a one half of a positive half cycle, and waveforms in which power is supplied in part of a positive cycle after no power supply during one half of a negative half cycle, or b) waveforms in which power is supplied in part of positive and negative half cycles in order after no power supply during one half of a negative half cycle, and waveforms in which power is supplied in part of a negative half cycle after no power supply during one half of a positive half cycle.