| 摘要 |
PURPOSE:To prevent the sticking of a developer to a non-image part by providing a removing means which removes the developer on a developing sleeve by sucking away the same to a titled device and removing the developer in the unnecessary region on the developing sleeve. CONSTITUTION:The suction means such as suction motor 23 which removes the developer 18' on the developing sleeve 13 by sucking away said developer is provided to remove the developer In the unnecessary region on the sleeve 13. If, for example, all valves 21 are held closed, the developer 18' coated on the sleeve 13 is not sucked by nozzles 20 and therefore the electrostatic latent image on a photosensitive drum 10 is visualized by the developer 18' on the sleeve 13. On the other hand, when the valves 21-1-21-3, 21-(n-2)-21-n are opened, the developer 18' on the sleeve 13 is sucked by the nozzles 20-1-20-3, 20-(n-2)-20-n corresponding to these valves and is removed from the sleeve 13, thus the electrostatic latent image is not visualized even if such image exists on the drum 10. The visualizing region of the electrostatic latent image on the drum 10 is thus controlled by controlling the opening and closing of the valves 21-1-21-n. |
