Image forming apparatus

Patent metadata

Field	Value
Publication number	US-8942604-B2
Application number	US-201213472897-A
Country	US
Kind code	B2
Filing date	May 16, 2012
Priority date	Jun 16, 2011
Publication date	Jan 27, 2015
Grant date	Jan 27, 2015

Abstract

An image forming apparatus includes a primary transfer device to transfer a toner image formed on a photosensitive member onto an intermediate transfer member formed into a loop, a secondary transfer device disposed outside the looped belt to contact the intermediate transfer member to form a secondary transfer nip therebetween and transfer the toner image from the intermediate transfer member onto a recording medium, a first power supply to apply a constant-current controlled direct current bias to an inner circumferential side of the intermediate transfer member, and a second power supply to form an alternating electric field between the intermediate transfer member and the recording medium. The direct current bias has the same polarity as that of the toner image. The first power supply and the second power supply apply predetermined biases simultaneously when the recording medium is in the secondary transfer nip to transfer the toner image thereon.

First claim

What is claimed is:

1. An image forming apparatus, comprising:
a photosensitive member to bear an electrostatic latent image on a surface thereof;
a developing device to develop the electrostatic latent image formed on the photosensitive member using toner to form a toner image;
an intermediate transfer member to bear the toner image on the surface thereof, the intermediate transfer member disposed opposite the photosensitive member and formed into a loop;
a primary transfer…

Assignees

• Ogiyama Hiromi
• Ricoh Co Ltd

Inventors

• Ogiyama Hiromi

Classifications

• G03G15/1605

  Physics · mapped topic

• G03G15/0189

  Physics · mapped topic

• G03G2215/0129

  Physics · mapped topic

• G03G15/1675 Primary

  Physics · mapped topic