| 摘要 |
PURPOSE:To prevent contactors of an electrostatic charging roller from setting and prevent the unevenness of charging by changing the directions of rotation of the charging roller in normal and reverse rotations every time the charging treatment is completed once or several times. CONSTITUTION:When a photosensitive drum 2 is charged, the charging roller 1 consisting of a roller body 1a and a fiber brush 1b is rotated as shown by an arrow A and a voltage is applied to the charging roller 1 to charge the surface of the photosensitive drum 2 by contact friction through tips of the fiber brush 1b. At this time, the charging roller 1 is reversed in the opposite direction of the arrow A every time the photosensitive drum 2 is charged once, so the force of contacting applied to the fiber brush 1 changes its direction and the fiber brush 1b is prevented from setting. |
