Patent · US Expired

Contact charging image forming apparatus having improved image transfer

US5708929A · kind A · utility

6Cited by
5References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 13, 1996
Grant dateJan 13, 1998
Priority date
Expiry dateMar 13, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G2221/0005
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

In an image forming apparatus, when a transferred material exists in a transfer position between a photoreceptor drum and a transfer unit during an image forming operation, a transfer voltage, which has opposite polarity to that of a voltage applied to a brush charger and is used for transferring a developer image on the photoreceptor drum onto the transferred material is applied to the transfer unit. Meanwhile, when a transferred material does not exist in the transfer position during the image forming operation, a non-transfer voltage, which is lower than the transfer voltage, is applied to the transfer unit. As a result, defects on an image due to returning of a developer from the brush charger to the photoreceptor drum can be prevented from being generated.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.