| 摘要 |
PURPOSE:To form good images for a long period by providing the second magnetic field generating means on the outside of a developer holding member and generating a magnetic field, which exists in a developer supply vessel, between this means and a fixed magnetic field generating means. CONSTITUTION:Magnetic particles in a developer supply vessel 3 form a magnetic brush 6 by the action of the magnetic field generated between the N pole of a magnet 7 and a control blade 8. A developer holding member 2 is rotated to agitate and mix magnetic particles and a nonmagnetic developer while holding the magnetic brush 6. In this state, movement of the mixture of the developer and magnetic particles is stopped by the blade 8 in the control blade 8 side of the vessel 3 and is raised and is moved circularly in the direction of an arrow C and is triboelectrified by mixing. The electrostatically charged developer is applied onto the surface of the developer holding member 2 uniformly and thinly with the magnetic brush 6, which is formed near the control blade 8, by an image force and reaches a position facing a photosensitive drum. |
