Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
IMAGE FORMING APPARATUS
Document Type and Number:
Japanese Patent JP2011145714
Kind Code:
A
Abstract:

To provide an image forming apparatus, preventing an exposure trace on the surface of a photoreceptor drum caused by an optical sensor from being left in a transfer image.

A control part 115 controls an exposure device 111 to form a density detecting toner image on the photoreceptor drum 110, and the density detecting toner image is detected by the optical sensor 106. The optical sensor 106 applies LED light to the density detecting toner image, so that a surface potential difference between an irradiated part of the photoreceptor drum 110 and a non-irradiated part thereof is enlarged to leave the exposure trace. Then, the control part 115 causes a transfer power supply 114 to output a recovery bias voltage opposite in polarity to the normal transfer bias voltage in timing when the density detecting toner image passes a primary transfer roller 113. The recovery bias voltage applied to the primary transfer roller 113 recovers the surface potential of the irradiated part of the photoreceptor drum 110 in the direction of the primary charging.


Inventors:
UNO MASAMI
TOMIZAWA TAKASHI
Application Number:
JP2011100312A
Publication Date:
July 28, 2011
Filing Date:
April 28, 2011
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
CANON KK
International Classes:
G03G21/00; G03G13/16; G03G15/00; G03G15/01; G03G15/16; G03G21/14
Domestic Patent References:
JPH096067A1997-01-10
JP2001166558A2001-06-22
Attorney, Agent or Firm:
Kazuo Chikajima
Yoshiro Sakamoto