The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Dec. 17, 1991

Filed:

Apr. 17, 1991
Applicant:
Inventors:

Yasushi Ishikawa, Tokyo, JP;

Fumio Tomono, Tokyo, JP;

Tetsuya Fujita, Tokyo, JP;

Assignee:

Seikosha Co., Ltd., Tokyo, JP;

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G03G / ;
U.S. Cl.
CPC ...
118658 ; 118657 ; 355251 ; 355253 ;
Abstract

A developing device for use in an electrophotographic printer comprises a non-magnetic cylindrical developing sleeve for conveying magnetic toner on its surface in rotating condition, a toner supply unit for supplying the magnetic toner onto the developing sleeve, a fixed magnetic field generating member disposed inside the developing sleeve, and a doctor blade unit disposed in confronting relation to the surface of the developing sleeve for regulating the layer thickness of the magnetic toner. The doctor blade unit includes a pair of magnetic pole plates whose distal ends are spaced a given distance from each other and magnetized as to exhibit opposite magnetic polarities. The fixed magnetic field generating member has a notch formed in a section facing the magnetic pole plates such that its magnetic flux does not act virtually on the magnetic pole plates.


Find Patent Forward Citations

Loading…