| 摘要 |
PURPOSE: To obtain an image forming device usable for a long term by recording an image with an electrostatic charging voltage different from that at a normal recording time in the case the ratio of a black image in image data to be recorded is larger than the reference value of the black image ratio, that is, by adjusting/controlling the electrostatic charging voltage and recording the image to reduce load on an electrostatic charging part (electrostatic charger). CONSTITUTION: The ratio of the black image in the image data supplied to a printer part is measured by an image ratio measuring means for measuring the ratio of the black image in the whole original. In the case the measured ratio of the black image in the image data is equal to or below the reference value of the set black image ratio, the electrostatic charger 5, a transfer charger 8 and a separating charger are controlled by a CPU through each driving circuit so that recording may be executed by a voltage applied at the normal recording. In the case the measured ratio of the black image in the image data is larger than the set reference value, the electrostatic charger 5, the transfer charger 8 and the separating charger are controlled by the CPU through each driving circuit so that recording may be executed by a voltage different from the voltage applied at the normal recording. |
