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.
Patent No.:
Date of Patent:
Aug. 06, 1991
Filed:
May. 30, 1990
Applicant:
Inventors:
Assignee:
Ricoh Company, Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G03G / ;
U.S. Cl.
CPC ...
355246 ; 355204 ; 355214 ;
Abstract
A method of controlling the density of images produced by an electrophotographic image forming apparatus to a constant value. A toner density sensor is provided with a first reference level variable in response to the output of an image density sensor, and a second reference level representative of a state associated with the optimum condition of a developer (e.g. immediately after replacement thereof). During usual control, the toner concentration of the developer is detected on the basis of the output of the toner density sensor, and the toner supply to the developer is controlled on the basis of the result of comparison of the detected toner concentration and the first reference level.