Patent ID: 9098005
Filing Date: 2015-08-04
Classification: G03G

Abstract:
1. An image forming apparatus comprising: a rotatable image bearing member configured to bear an electrostatic latent image; a plurality of development devices, each device including a developer bearing member configured to bear a developer for developing the electrostatic latent image; a rotatable development device supporting member configured to support the plurality of development devices, wherein the developer bearing member is configured to execute development while contacting the image bearing member at a development position via the developer, wherein the developer bearing member rotates in the same direction as a rotating direction of the image bearing member at the development position and a surface moving speed of the developer bearing member is faster than a surface moving speed of the image bearing member, wherein the development device supporting member rotates so that the development device supporting member changes a developer bearing member existing at the development position to another developer bearing member, and wherein a first relative speed of a surface moving speed of the developer bearing member with respect to a surface moving speed of the image bearing member when the developer bearing member is about to abut on or is about to separate from the image bearing member becomes higher than a second relative speed of the surface moving speed of the developer bearing member with respect to the surface moving speed of the image bearing member when the electrostatic latent image is developed; and wherein a first potential difference is a potential difference during the first relative speed between a potential of a bias applied to the developer bearing member when the developer bearing member is about to abut on or is about to separate from the image bearing member and a potential of a non-image area of the image bearing member when the electrostatic latent image is developed, wherein a second potential difference is a potential difference during the second relative speed between the potential of the bias applied to the developer bearing member when the electrostatic latent image is developed and a potential of a non-imaging area of the image bearing member when the electrostatic latent image is developed, wherein the first potential difference is higher than a second potential difference.