Patent ID: 7668480
Filing Date: 2010-02-23
Classification: G03G

Abstract:
1. A cleaning device for use with an electrophotographic image forming apparatus, comprising: a charging brush positioned in contact with an endless image bearing surface of a rotatable image bearing member to form a contact region in which the brush provides an electric charge with a certain polarity to toner particles passing through the contact region according to a rotation of the image bearing member; and a cleaning member positioned on a downstream side with respect to a rotational direction of the image bearing member and in contact with the image bearing surface of the image bearing member to collect the toner particles from the image bearing surface; wherein the charging brush has a base and a number of bristles planted in the base, and a contact force of the brush against the image bearing surface is set to be more than 0 N/m and equal to or less than 1.5 N/m, which is defined by a following equation: wherein “y” is defined by a following equation: F: Contact force of charging brush y: Deflection of bristle (m) E: Young's modulus of bristle (N/m I: Geometric moment of inertia of bristle (=πd d: Diameter of brush D: Density of bristles (number/m L: length of bristle (m) Δu: Tip offset of contacted brush (m).