To improve the safety of an image forming apparatus equipped with a power unit which can be charged.
When it is time T1' being the time before time T1 when the operation of the image forming apparatus is stopped (for example, finishing time), power is supplied to an auxiliary heat source 384b from a capacitor C in an auxiliary power unit 3 by the control of a control unit 2. The time T1' is defined as "(the time T1)-(time difference ΔT1)", and the time difference ΔT1 is time longer than time required for discharging the capacitor C to a safe voltage level. By starting the discharge of the capacitor C at the time T1', the voltage of the capacitor C is lowered to a safe level by the time the operation stop time T1 comes, so that the safety of the image forming apparatus is guaranteed. For example, since the voltage of the capacitor C shows the safe level by the time the finishing time comes, the safety of the image forming apparatus is guaranteed even in circumstances that there is no person or a few persons at and after the finishing time.
GOTO KATSUAKI
SASAMOTO YOSHIFUMI
OKUTOMI TAKAHARU
