| 摘要 |
PROBLEM TO BE SOLVED: To improve the image quality without any great deterioration in productivity. SOLUTION: The rotary developing device is constituted of a developing device supporting member rotation drive device with which a developing device supporting member H, supporting developing devices GY to GK, is rotated in one direction and having it stopped at a 1st stopping position where a black developing device GK is stopped at a developing position P1, a 2nd stopping position that is rotated 90 deg. from the above mentioned 1st stopping position and a 5th stopping position that is a standby position that is deviated from the developing position P1 and a developing device supporting member rotation control means with which the black developing device GK that is installed more upstream from the developing position P1 in the direction of rotation and in a position closest to the developing position P1 and the developing device supporting member H are moved to and stopped at the before mentioned standby position after developing is finished of a black toner image at the developing position P1 and in the case of color developing, they are moved to and stopped at the before mentioned 2nd stopping position and then after the developing action of each developing device GY to GY is completely finished, they are moved to and stopped at the before mentioned standby position. |
