Patent · US Active

Image forming apparatus and image forming method

US8032043B2 · kind B2 · utility

0Cited by
0References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 4, 2009
Grant dateOct 4, 2011
Priority date
Expiry dateApr 6, 2030

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G15/0879
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

In case new and old toners may be mixed, a developing bias is set as follows. The time is first clocked. The number of times toner is replenished from a hopper into a buffer for a clocked period is counted. If a replenishment amount per clock time is a threshold value or higher, considering that new and old toners are mixed, the setting of the developing bias is changed. An electric field intensity between a developing roller and a photoconductor is set to cause normally-charged toner to fly in an image area but not to fly in a background area. No image fogging is therefore generated in the background area. Thus, an image forming apparatus and method capable of preventing low-charged toner and oppositely-charged toner generated by mixing of new and old toners from adhering to the background area of an electrostatic latent image on the photoconductor, thereby avoiding generation of image fogging.

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