摘要 |
A heating device includes a heating unit, a main power supply device configured to supply an electric power to the heating unit from an external power supply, an auxiliary power supply device configured to be chargeable by use of the external power supply, and a charger configured to charge the auxiliary power supply device during formation of an image while neither the main power supply device nor the auxiliary power supply device is supplying an electric power to the heating unit, such that a maximum limit of a charge amount of the auxiliary power supply device is set to a predetermined amount smaller than a full-charge amount of the auxiliary power supply device. |