| 摘要 |
PROBLEM TO BE SOLVED: To stably form an image having excellent image quality by suppressing noise due to charge stored on a toner carrier. SOLUTION: A fixed electrode (ground electrode) 150A is disposed at the most proximate conjugate position where it is the most proximate to a fixed electrode (bias supply electrode) 150D on the upstream side in a rotating direction D3. Therefore, when a black developing device is positioned at a developing position, a magenta developing device to be positioned at the developing position next to the black developing device is positioned at the conjugate position, and a developing roller 44M is grounded through an electrode 48M and the fixed electrode 150A. As a result, the charge stored on the developing roller 44M is discharged before developing processing, thereby drastically suppressing the noise due to the charge stored on the developing roller 44M when the magenta developing device is positioned at the developing position. COPYRIGHT: (C)2008,JPO&INPIT |
