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:
May. 10, 1994
Filed:
Feb. 09, 1993
Applicant:
Inventors:
Shiro Nakagawa, Chiba, JP;
Taisuke Domon, Ichikawa, JP;
Takehiro Imai, Ichikawa, JP;
Eiji Takahishi, Ichikawa, JP;
Assignee:
TDK Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B05C / ; G03G / ;
U.S. Cl.
CPC ...
118689 ; 355246 ;
Abstract
A toner concentration detecting device for detecting a toner concentration of a two component developer including a differential transformer which is connected with a phase detecting circuit. A variable capacitance diode is connected between the primary coil and the secondary coil and a variable resistor is provided to supply the variable capacitance diode with a DC voltage to vary the capacitance of the diode. The variable resistor and DC voltage are located at a remote location from the transformer.