JP2764316B

PURPOSE:To surely cool a power source and an electric parts assembled substrate by consecutively operating a fan cooling the power source and the substrate even if a unit dividing a device main body is opened. CONSTITUTION:The upper unit 10a of a laser printer is hinged to be opened with respect to a lower unit, and is provided with the fan 43, which simultaneously cools a power source unit 33 and the substrate 34 and remove ozone around a photosensitive body, and an exhaust fan 51. When the unit 10a is opened, a prescribed switch is moved to an open position to stop the fan 51. However, the fan 43 and the substrate 34 are not disconnected to a low voltage power source to continuously operate. Consequently, even if the unit 10a is opened, contents stored in the memory of the substrate 34 are not erased, and the substrate 34 and the unit 33 are continuously cooled.