| 摘要 |
<p>PURPOSE:To reduce the cost of an image forming device main body by providing a member which changes the set conditions of the various processes of the image forming of the image forming device main body on an automatic both-side unit. CONSTITUTION:The automatic both-side unit is provided with a power source 36 to supply a bias voltage to a fixing roller 18. When the automatic both-side unit 2 is attached to the main body 1, terminals 35 and 35' in the main body 1 are connected with the power source 36. The terminal 35 is electrically connected to the fixing roller 18, and the bias voltage having the same polarity as toner is impressed on the fixing roller 18. Consequently, offset which easily occurs on the second surface at the time of the both-side printing is effectively prevented, so that a good image can be obtained. And when the automatic both-side unit 2 is detached from the main body 1, the terminal 35 and the terminal 35' are shorted and the fixing roller 18 is grounded. Therefore, since the offset does not occur even when one side printing is performed, the good image can be obtained. Thus, the power source of the image forming device 1 can be reduced.</p> |
