| 摘要 |
PROBLEM TO BE SOLVED: To provide a developing device capable of reducing driving torque and maintaining high image quality for a long period by setting the magnetic developer of a quantity for obtaining a desired service life. SOLUTION: The device is constituted to provide a sleeveless developing roller 4 consisting of a magnet member whose surface is moved in a state where the developer 3 including toner and magnetic carriers is carried on this surface where plural magnetic poles are arranged, so as to carry the developer 3 to a developing region A facing a photoreceptor drum 1 and a doctor 5 for removing a part of the magnetic developer on the developing roller 4 and regulating the thickness of a layer of the developer on the developing roller 4 for attaining carrying to the developing region A. In such a case, a part of the developer 3 removed from the developing roller 4 is guided to a region where magnetic constraining force exerted on the developer 3 is smaller than gravity, by the doctor 5 and a part of the developer guided by the doctor 5 is supplied to a supplying position in which the magnetic constraining force is greater than the gravity and which is adjacent to the doctor 5 from the upstream side in the rotational direction of the developing roller, by an agitator 6. |
