| 摘要 |
PURPOSE:To adjust a cleaning bias voltage and obtain expected stable cleaning effect by varying a voltage impressed to a magnetic brush roll according to the amount of toner in a cleaner. CONSTITUTION:An electrostatic latent image when formed on a photosensitive body 1 rotating as shown by an arrow is developed at a developing part 3 to form a toner image corresponding to the electrostatic latent image, and this image is transferred onto a form 5 by a transfer part 4. Then, toner on the surface of a photosensitive body 1 which is not transferred onto the form 5 is removed by a cleaning device 6, but a sleeve 7 is impressed with a bias voltage E1 from a bias power source 9 so that its polarity is opposite to the charge of toner on the photosensitive body 1 and comes into slide contact with the surface of the photosensitive body 1 while rotating as shown by an arrow, separating the toner from the surface of the photosensitive body 1 with the assistance of the cleaner 8. Simultaneously, an attracting roller 12 is impressed with a bias voltage E2 from a bias power source 13 so that its polarity is opposite to that of the charge on the sleeve 7 and slides on the cleaner 8 on the sleeve 7 in contact while rotating as shown by an arrow, attracting and removing the toner in the cleaner 8. |
