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:
Apr. 27, 2004
Filed:
Sep. 04, 2001
Applicant:
Inventors:
Assignee:
Ricoh Company, Ltd., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
G03G 1/509 ;
U.S. Cl.
CPC ...
G03G 1/509 ;
Abstract
A developing device of the present invention includes an image carrier for forming a latent image thereon, and a developer carrier for depositing a developer thereon in the form of a magnet brush. The magnet brush is caused to contact the latent image to thereby develop it. The developer carrier includes a main magnetic pole for development and an auxiliary magnetic pole adjoining the main pole and helping the main pole exert a magnetic force. The developer carrier and said image carrier are spaced by a gap of 0.35 mm or above, but 0.5 mm or below. The developer carrier has a carrier packing ratio of 15% or above, but 45% or below, measured at the developing region.