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. 01, 2008
Filed:
Aug. 05, 2004
Noriyuki Kamiya, Yokohama, JP;
Takahiro Yasunaga, Ebina, JP;
Tsuyoshi Imamura, Sagamihara, JP;
Sumio Kamoi, Tokyo, JP;
Kyohta Koetsuka, Fujisawa, JP;
Mieko Kakegawa, Atsugi, JP;
Noriyuki Kamiya, Yokohama, JP;
Takahiro Yasunaga, Ebina, JP;
Tsuyoshi Imamura, Sagamihara, JP;
Sumio Kamoi, Tokyo, JP;
Kyohta Koetsuka, Fujisawa, JP;
Mieko Kakegawa, Atsugi, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A development magnet roller for use in a development roller of an electrophotographic image forming apparatus is provided. The development magnet roller has a development pole to form a magnetic field causing a developer born on a surface of the development roller including the development magnet roller to rise in a form of a series of ears in a development area of the image forming apparatus where the development roller opposes an image bearing member, and in a magnetic flux density distribution in a normal line direction of the development pole, a peak magnetic flux density is 120 mT or greater, a zero gauss region width is 70° or greater, and a half-value region width is 40° or smaller.