Patent ID: 7941064
Filing Date: 2011-05-10
Classification: G03G

Abstract:
1. An image forming apparatus for transferring a toner image formed on a latent image carrier to a recording medium to output an image, comprising: a charging portion for charging a surface of the latent image carrier; a developing device for developing an electrostatic latent image formed on the surface of the latent image carrier as a toner image; a developing bias applying portion for applying a developing bias voltage to the developing device; a surface potential sensor for measuring a surface potential of the latent image carrier; an image density sensor for detecting an image density of the toner image formed on the surface of the latent image carrier; and a control portion for controlling an output value of the developing bias applying portion, wherein the control portion adjusts the developing bias voltage based on an average print coverage of document in previous printing jobs and an effective developing bias voltage which is based on the measured surface potential of the latent image carrier.