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:
Aug. 10, 2004
Filed:
Nov. 01, 2001
Hirohide Inayama, Yamatokoriyama, JP;
Tomofumi Takahashi, Komaki, JP;
Minoru Kitabayashi, Nagoya, JP;
Koyo Seiko Co., Ltd., Osaka, JP;
Abstract
In a brushless DC motor constructed by a rotor to which a permanent magnet is attached; and a stator having a plurality of slots, when an effective opening angle of magnetic pole of the rotor that was set to a predetermined opening angle whose base is the rotation axis of the rotor is &thgr;2 and a salient area opening angle of magnetic pole formed within the effective opening angle &thgr;2 of magnetic pole is &thgr;3, the opening angles &thgr;2 and &thgr;3 are set so that cogging torque generated by the effective opening angle &thgr;2 of magnetic pole and cogging torque generated by the salient area opening angle &thgr;3 of magnetic pole are mutually in antiphase. Accordingly, a brushless DC motor capable of reducing cogging torque is realized.