PURPOSE: To improve image quality and extend the life of a carrier by preventing excessive accumulation of a developer on the tip part of a cleaning blade with a thin plate member to prevent the occurrence of filming on the surface of the image carrier.

CONSTITUTION: While the remaining developer is scraped by a cleaning blade 40, the developer rises around a tip part 40a of the blade 40 and is brought into contact with a thin plate member 47 at the rear of the blade 40. Since the member 47 is always oscillated by the contacting operation between the blade 40 and a photosensitive body 25 during the copying operation, a free end part or a tip part 47a of the member 47 is lightly oscillated in a very minute range by this oscillation. Therefore, oscillation of the member 47 is transmitted to the developer by this oscillating action and the elastic action of the member 47 itself. Then, a light beating action acts always upon the developer to break the rise form in the blade tip part 40a, and the developer is dropped positively little by little.