| 摘要 |
PROBLEM TO BE SOLVED: To prevent the generation of a stained image caused by deficiency in the electrification of a toner by applying a bias voltage to a developer regulating member with a bias voltage applying means and forming an electric field to a gap between the developer regulating member and a developer carrier. SOLUTION: This developing device is provided with a doctor biasing power source 12 for applying a bias voltage for forming an electric field in a gap between a doctor 6 as a developer regulating member and a developing sleeve 4 as a developer carrier. That is, the setting of the doctor bias voltage for forming the electric field in the doctor gap Gd can be changed by controlling the doctor bias power source 12 with a doctor bias control part 13. Therefore, electrostatic constraining force is exerted on a developer 3 trying to pass through the doctor gap Gd. The electrification of the toner of the developer 3 can be excellently started by the friction between the developer 3 trying to be retained in the doctor gap Gd and the developer 3 trying to be held/carried with the developing sleeve 4 by the exertion of the constraining force. |
