CHARGING DEVICE AND IMAGE FORMING APPARATUS HAVING THE SAME

摘要

PROBLEM TO BE SOLVED: To ensure the uniform charging of the surface of a photoreceptor drum for a long period. SOLUTION: A magnetic brush charger 3 as a main charger is disposed downstream of the photoreceptor drum 1 in the direction of its rotation (the direction of the arrow R1). A contact charging roller 2 as a sub-charging member for a sub-charger is disposed upstream of the magnetic brush charger 3. The contact charging roller 2 is in contact with the surface of the photoreceptor 1 by gravity. The longitudinal flexure of the contact charging roller 2 is prevented to make the pressure distribution of it uniform. This restrains the longitudinal nonuniform charging and prevents partial power supply deterioration resulting from pressure dependance. Minute nonuniform charging that may occur by the contact of its gravity is made uniform by the magnetic brush charger 3 located downstream. COPYRIGHT: (C)2005,JPO&NCIPI