Patent · US Expired

Image forming apparatus having contact charger

US5689777A · kind A · utility

5Cited by
9References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 9, 1995
Grant dateNov 18, 1997
Priority date
Expiry dateNov 9, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G15/0216
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An image forming apparatus includes a charging rotary brush in contact with a photosensitive member, a laser beam irradiator to form an electrostatic latent image, a developing unit for developing the latent image into a visible image and collecting residual developer remaining on the surface of the photosensitive member after the visual image is transferred to a transfer material, and a power source unit for applying to the charging rotary brush an oscillating voltage fulfilling the requirement of: EQU .DELTA.t<L/Vpc or .DELTA.t>3.times.L/Vpc wherein .DELTA.t is the time taken for the oscillating voltage to vary between .+-.300 V above and below the central oscillating voltage value between the peaks of the voltage, L is the printing pitch, and Vpc is the speed of movement of the surface of the photosensitive member.

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