| 摘要 |
PURPOSE:To effectively prevent the scattering of a toner by placing a magnetic member which is opposed adjacently to a developer carrying member and brought to face movement driving in the same direction as the carrying direction of a developer, in apart where a residual developer progresses into a developer chamber. CONSTITUTION:On a part where the residual developer returned and carried from a developing part side progresses into the developer chamber, a magnetic material roller 12 is provided so as too be opposed adjacently to the lower face of a developing sleeve 71. By a magnetic field by the magnetic pole S2 of a magnet roller 72 working on an opposed gap part of the magnetic material roller 12 and the developing sleeve 71, a magnetic grain portion contained in the developer becomes a magnetic brush-like state Tc. The toner portion scattered due to the influence of turbulence P and the vibration of the device, etc., is caught by the insulating covering 12a surface of the magnetic material roller 12 to which a bias voltage is applied, adsorbed electrically, taken successively into the magnetic brush Tc by following up a face movement by the rotation of the magnetic material roller 12, and carried into the developer chamber side together with the residual developer which is returned and carried. |
