| 摘要 |
PROBLEM TO BE SOLVED: To properly control a charge bias potential of a heating roller in response to an environmental change, by simple constitution, by changing a rating of a Zener diode arranged in a grounding route for grounding the heating roller, in response to a temperature and a humidity, to reliably prevent transfer blurring and an electrostatic offset from being generated, and to form an image of high quality. SOLUTION: The image forming device has a fixing device including the heating roller 26 and a pressurizing roller 27, the plurality of Zener diodes 31 different in ratings arranged in the grounding route for grounding the heating roller 26, a change-over switch for selecting any of the Zener diodes 31, a sensor for detecting the temperature and the humidity, and a control means for controlling an operation of the change-over switch, and the control means controls the operation of the change-over switch, in order to select the Zener diode 31 of the rating corresponding to the temperature and/or the humidity detected by the sensor. COPYRIGHT: (C)2009,JPO&INPIT
|
