| 摘要 |
<P>PROBLEM TO BE SOLVED: To supply toner to a head section from the toner storage section of a developing unit used for monochrome image formation in a monochrome image formation mode, while suppressing a decrease in image productivity and efficiently using toner in a developing unit. <P>SOLUTION: In the monochrome image formation mode, when a quantity of toner use in a developing unit 4K mounted on a developing unit rack 4H used for image formation is equal to or greater than a predetermined quantity of use as a result of a measurement by a toner use quantity measuring means from the start of image formation, the rack 4H is turned reciprocally and toner t is supplied to the head section 42 from the toner storage section 41 of the developing unit 4K. In addition, according to the integrated quantity of toner use in the developing unit 4K measured by the toner use quantity measuring means, the smallest angle that allows toner supply is selected from a plurality of predetermined angles as the angle by which the rack is reciprocally turned at the time. <P>COPYRIGHT: (C)2009,JPO&INPIT |
