| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image-forming apparatus preventing damages to a communication control means, such as a CPU of the side of optional equipment. <P>SOLUTION: An image-forming apparatus is provided with a constant-voltage power source for supplying DC voltage to a first load system and a voltage changer means for changing a voltage value of the DC voltage outputted from the constant-voltage power source and supplying the DC voltage, after change to a second load system at least including the communication control means controlling communication with optional equipment. The image-forming apparatus supplies the DC voltage outputted from the constant voltage power source to the connected optional equipment. In addition, the image-forming apparatus is provided with a power source shut off means stopping supply of the DC voltage from the voltage changer means, when the DC voltage outputted from the constant-voltage power source is lower than a prescribed threshold. <P>COPYRIGHT: (C)2008,JPO&INPIT |
