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:
Nov. 25, 2008
Filed:
Dec. 13, 2007
Applicants:
Masato Gomyo, Kyoto, JP;
Mineo Kurita, Kyoto, JP;
Masayoshi Saichi, Kyoto, JP;
Inventors:
Assignee:
Nidec Corporation, Kyoto, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02K 1/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
In a spindle motor, a core includes a plurality of core plates, which are laminated one on another. The core is constituted by laminating two cores, that is, a first core and a second core, which are different from each other in shape of a surface facing to a rotor magnet. At least a part of a cogging torque generated at the second core can be cancelled by a cogging torque generated at the first core.