Patent · US Expired

Image forming apparatus

US5930556A · kind A · utility

20Cited by
9References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 6, 1998
Grant dateJul 27, 1999
Priority date
Expiry dateJul 6, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G2215/0141
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

The image forming apparatus has a first through a fourth image forming stations which form images in respective colors. Under theses image forming stations, there is provided the transfer belt to convey a paper. Inside the transfer belt, transfer rollers are arranged to apply prescribed transfer bias voltage to the image carriers of the image forming stations. When, for instance, a monochromatic image is formed at the fourth image forming station, 500V transfer bias voltage is applied to the transfer rollers of the first through third image forming stations and 1,00V transfer bias voltage is applied to the transfer roller of the fourth image forming station. Thus, it is possible to prevent undesirable charge-up to the paper and form monochromatic image of good quality.

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