| 摘要 |
<P>PROBLEM TO BE SOLVED: To realize a structure capable of reducing the occurrence of image failures such as toner stripe, etc., without regard to usage of a developer. <P>SOLUTION: In the case of paper interval time x 400 ms or more at a paper interval in the state of non-developing operation, developing drive and developing AC bias are turned off, and developing DC bias is switched. The switching of developing DC bias makes Vback smaller when the counted number of image-forming sheets becomes larger. This makes it difficult for toner to attach to a developing sleeve even when there are many image-forming sheets which cause a tendency of a toner charge amount to decrease, and reduces the occurrence of image failures. <P>COPYRIGHT: (C)2012,JPO&INPIT |
