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. 21, 1996
Filed:
Nov. 08, 1994
Applicant:
Inventors:
Tomoe Hagiwara, Fuji, JP;
Mitsuo Aoki, Numazu, JP;
Masanori Suzuki, Suntou, JP;
Tomio Kondou, Numazu, JP;
Takahisa Kato, Numazu, JP;
Assignee:
Ricoh Company, Ltd., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
G01N / ; G03G / ;
U.S. Cl.
CPC ...
324204 ; 118690 ; 355208 ;
Abstract
In an electrophotographic or electrostatic image forming device, the toner concentration of a two-component developer, i.e., a mixture of toner and carrier is measured on the basis of an output of a magnetic bridge type concentration sensor responsive to the magnetic permeability of the developer. The sensor has a surface whose mean roughness along the center line is less than 0.4 .mu.m Ra.