| 摘要 |
PURPOSE:To eliminate an irregularity in the density of an image and to obtain a stable development quantity by setting the rotary angular velocity of a magnet roller and the number of magnetic poles so that the radii and rotary angular velocities of a latent image carrier and the magnet roller and the number and development nip width of magnetic poles of the magnet roller satisfy a specific relational inequality. CONSTITUTION:The rotary angular velocity omegam and the number 2p of magnetic poles of the magnet roller 7 are so set that the inequality holds, where rd and omegad are the radius and rotary angular velocity of the latent image carrier 1, rm and omegam the radius and rotary angular velocity of the magnet roller 7, and (d) the nip width of the magnet roller 7. When omegam or 2p is made large, a magnetic force varies repeatedly at a short period in the development time when one point on the carrier 1 passes a nip part and the magnetic brush of a developer becomes rough and fine repeatedly. Therefore, a similar developing force distribution and a developer supply amount are obtained at any development position and the stable development quantity is obtained. |
