| 摘要 |
<P>PROBLEM TO BE SOLVED: To accurately detect toner concentration according to a quantity of developer in a developing unit, which changes accompanying the supply of developer. <P>SOLUTION: The image forming apparatus (U) comprises: the developing unit (G) having a developer discharge port (7) for discharging developer in a developing container (V), and used to develop an electrostatic latent image into a toner image with the developer; a cumulative drive quantity measuring means (C5) for measuring the cumulative quantity (tr) by which developer supply units (11 to 17+G5) have been driven is measured; a toner concentration detecting member (SN2) for detecting the toner concentration; a concentration correcting means (C7) for correcting a target toner concentration (TCO) based on the cumulative quantity (tr) by which the developer supply units have been driven; and a supply unit driving means (C9B) by which, based on the corrected target concentration obtained by the concentration correcting means, the developer supply units (11 to 17+G5) are driven so that the toner concentration reaches the target toner concentration. <P>COPYRIGHT: (C)2008,JPO&INPIT |
