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:
Oct. 06, 2015
Filed:
Mar. 04, 2011
Makoto Iwasaki, Tokyo, JP;
Fumitaka Baba, Tokyo, JP;
Satoshi Tanaka, Tokyo, JP;
Hideki Sasaki, Tokyo, JP;
Takahide Kurahashi, Tokyo, JP;
Hitoshi Maro, Tokyo, JP;
Keiichi Morimoto, Tokyo, JP;
Seiichi Endo, Tokyo, JP;
Makoto Iwasaki, Tokyo, JP;
Fumitaka Baba, Tokyo, JP;
Satoshi Tanaka, Tokyo, JP;
Hideki Sasaki, Tokyo, JP;
Takahide Kurahashi, Tokyo, JP;
Hitoshi Maro, Tokyo, JP;
Keiichi Morimoto, Tokyo, JP;
Seiichi Endo, Tokyo, JP;
TDK CORPORATION, Tokyo, JP;
Abstract
In the rare earth sintered magnet, the ratio of R2 to the sum of R1 and R2 that are contained in crystal grain boundaries surrounding the crystal grains in the rare earth sintered magnet body is higher than the ratio of R2 to the sum of R1 and R2 in the crystal grains, and the concentration of R2 increases from the central portion of the rare earth sintered magnet body toward the surface of the rare earth sintered magnet body. In addition, the degree of unevenness in residual magnetic flux density on the surface of the rare earth sintered magnet body is smaller than 3.0%.