| 摘要 |
PURPOSE:To prevent generation of fog simply, by providing a means which periodically disturbs magnetic lines of force of a development region with a photoreceptor belt carrying roller opposing to a magnetic brush developing roller. CONSTITUTION:A plurality of permanent magnets 13 are provided along the circumference of a sleeve 10 turning counterclockwise, and a magnet 13a opposing to a roller 2 belted with a photoreceptor belt 1 is constituted with a magnet with a groove 13b extended toward axial line of the sleeve. A plurality of wings 15 are radially provided toward radial direction of the roller 2, and a part of the wings is constituted with a magnetic substance. The wings turn with the roller 2 to periodically disturbs the magnetic lines of force from magnetic poles 13c, 13d. In place of the wings, grooves or projections are provided on the roller shaft 16 or the roller itself, or magnetic substance is used partially for the case. |
