Patent · US Expired

Color image forming apparatus having bias controller for cleaning transfer roller

US5689771A · kind A · utility

13Cited by
9References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 23, 1996
Grant dateNov 18, 1997
Priority date
Expiry dateFeb 23, 2016

Classification

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

Abstract

A color toner image forming apparatus comprises a transferring roller having an average cell diameter of 1 .mu.m to 300 .mu.m to transfer a toner image from a photoreceptor drum to a sheet. During the transferring operation, the electric bias member applies onto the transferring roller an opposite electric bias of a constant current having the opposite electric polarity to that of the toner image, and during a cleaning operation to shift toner adhered on the transferring member to the photoreceptor, the electric bias member applies onto the transferring member alternately an identical electric bias of a constant voltage having the identical electric polarity with that of the toner image and an opposite electric bias of a constant current having the opposite electric polarity to that of the toner image six times or more.

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