| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming apparatus including a developer peeling mechanism which resolves poor peeling of a developer, which causes uneven developer supply to a developing roller of a developing unit, to form an image free of unevenness.SOLUTION: A developing roller 15 of a developing unit 14 incorporates a magnet roller 57, has the outer peripheral surface covered with a sleeve 58 and has a main pole N1 facing a photosensitive drum 10 and a developer peeling area formed between magnetic poles N3 and N2 on the opposite side of the main pole N1. A magnetic body 71 is attached to an inner wall surface of an enclosure 16 in an extension direction of a line of magnetic force of the magnetic pole N3 to largely intensify and extend the line of magnetic force 72 of the magnetic pole N3 which is originally equivalent to that of the magnetic pole N2. The developing roller 15 supplies toner to the photosensitive drum 10 and splashes a return developer brought into an upper development tank 42a and having a reduced toner density, far toward the magnetic body 71 along the line of magnetic force 72 of the magnetic pole N3 to shake off the return developer to the outside of an agitating conveyance screw 19 and newly pumps up a developer having toner and carrier mixed adequately in the upper development tank 42a. |
