JPH05333701

PURPOSE:To reduce remaining developer and to restrain napping so that irregularity in an image is prevented by displacing a magnet inside a developer carrier so that a magnetic force horizontal component in the vicinity of a point close to an image carrier becomes large at the time of non-developing. CONSTITUTION:Developer is recovered from a developing sleeve 31 at the time of finishing of developing, carrier remaining on the developing sleeve 31 is influenced by the magnetic fields of the magnets 71-73, especially by the magnetic field in the vicinity of a main pole 72 on a developing area in which failure occurs. That is, the chain of the carrier is formed and brought into contact or to come close to a photosensitive drum 17. Then after cutting the nap of the developer, the main pole 72 is displaced in the rotating direction on the upstream side of the developing sleeve 31 by an angle beta (beta>alpha) from a line connecting the center of the photosensitive drum 17 with that of the developing sleeve 31, so that the horizontal component of the magnetic field caused by the main pole 72 and the magnetic pole 73 on a downstream side becomes maximum. The horizontal component is the component in a direction at nearly orthogonal to the line connecting the center of the photosensitive drum 17 and that of the developing sleeve 31. Thus, the remaining carrier lies down by an intense horizontal magnetic field.