Patent · US Expired

Electrostatic printing apparatus comprising improved electrode drive means

US4262294A · kind A · utility

16Cited by
7References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 31, 1978
Grant dateApr 14, 1981
Priority date
Expiry dateJul 31, 1998

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB41J2/41
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

A sheet of copy paper (24) is moved perpendicular to a linear array (22) of printing electrodes (221, 222, 223, 224 . . . ). The electrodes (221, 222, 223, 224 . . . ) are selectively energized to form an electrostatic charge pattern on the copy sheet (24) corresponding to one horizontal scan line of an original document. The electrostatic charge pattern is developed by a toner and the resulting toner image fixed to the copy sheet (24). The electrodes (221, 222, 223, 224 . . . ) are divided into a first set (221, 223, 225 . . . ) and a second set (222, 224, 226 . . . ), the electrodes in the second set (222, 224, 226 . . . ) being alternatingly spaced from the electrodes in the first set (221, 223, 225 . . . ) along the length of the array (22). The first set (221, 223, 225 . . . ) of electrodes are selectively energized during a first time period (t1) and the second set (222, 224, 226 . . . ) of electrodes are selectively energized during a subsequent second time period (t2). The second time period (t2) may be made longer than the first time period (t1) and/or a voltage (V2) applied to the second set (222, 224, 226 . . . ) of electrodes may be made higher than a voltage (V1) appli…

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