Patent · US Expired

Image forming apparatus with constant voltage and constant current control

US5179397A · kind A · utility

45Cited by
20References
128Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 28, 1990
Grant dateJan 12, 1993
Priority date
Expiry dateMar 28, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G2215/1652
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An image forming apparatus includes a movable image bearing member; an image forming device for forming a toner image on the image bearing member; image transfer device for transferring the toner image from the image bearing member to a transfer material at an image transfer station, wherein the transfer device includes a charging member press-contacted or faced to the image bearing member and a device for applying a voltage to the charging member, wherein the voltage applying device applies a voltage to the charging member so that the charging member is constant-voltage-controlled when an image region of the image bearing member is in the transfer station, and the charging member is constant-current-controlled during at least a part of a period when it is not in the transfer station, wherein a voltage V2 applied during the constant voltage control is a voltage V1 appearing in the transfer device during the constant current control multiplied by a coefficient R, in which R is larger than 1.

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