Patent · US Expired

Control method of an electrophotographic record apparatus and image formation apparatus including controlling developing bias and photoconductor surface potential

US6686943B2 · kind B2 · utility

8Cited by
5References
20Claims
0Family size

Assignees

Inventors

Key dates

Filing dateJul 12, 2002
Grant dateFeb 3, 2004
Priority date
Expiry dateJul 12, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G2215/00037
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An image formation apparatus for keeping secularly stable image quality for all image patterns if change in the charge amount of a developer caused by environment variation or over time or change in the photoconductor characteristic occurs in electrophotographic record apparatus. A test patch image formed on a photoconductor by a parallel electric field is detected by an image density sensor, the developing bias and the photoconductor surface potential are controlled so that the density detected by the image density sensor becomes constant, a test patch image formed on the photoconductor by a peripheral electric field is detected by the image density sensor with the control condition of the image density sensor maintained, and the light application amount in which an image area of a several-dot width adjacent a blank paper part is exposed to light is controlled so that the density detected by the image density sensor becomes constant.

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