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:
Jan. 25, 1983
Filed:
Nov. 03, 1980
Koji Hirakura, Yokohama, JP;
Yasuo Sawada, Sayama, JP;
Kenta Watase, Tokyo, JP;
Takahiko Kitamura, Yokohama, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A toner concentration control apparatus of the type for allowing developer to pass through a chute, which is capable of detecting stopping of the flow of the developer in the chute, clogging of the chute with the developer, or coating of a viewing window formed in the chute with the developer, and upon occurrence of such abnormalities, minimizing the trouble therefrom in the operation of the copying machine, in which light from a single light source is simultaneously detected by two photosensors, the light striking one of the photosensors directly and the other after being reflected from the developer comprising toner and carrier particles as the developer passes a viewing window in the chute provided for the detection of the toner concentration within the copying machine, and the output of the photosensors is compared with each other and the concentration of toner in the developer can be determined and adjusted by the comparison value. In addition, the output of the photosensor which receives the light reflected from the developer contains an A.C. component signal which indicates the flow of the developer along the inside of the viewing window, and a D.C. component signal which corresponds to the concentration of toner in the developer, and, by detecting the presence or absence of the A.C. component signal, abnormalities in the flow of developer are detected.