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. 04, 2011
Filed:
Sep. 11, 2008
Toshiyuki Aso, Tokyo, JP;
Hiroshi Kaneshige, Tokyo, JP;
Akie Tanaami, Tokyo, JP;
THK Co., Ltd., Tokyo, JP;
Abstract
Provided is a linear motor capable of reducing cogging. The linear motor has a field magnet parthaving a plurality of permanent magnetsarranged to form N and S poles alternately; a corehaving a plurality of salient polesandarranged facing the field magnet part; and a three-phase coilwound around the salient polesandof the core. At respective sides in the moving direction of an armature having the three-phase coiland the core, auxiliary coresmade of a magnetic material are provided to sandwich the armature. The distance Pbetween a center of each auxiliary core and a center of a center salient poleis set to be substantially ¼×(2N+1)×a magnetic pole pitch between N poles of the field magnet part(N: an integer equal to or greater than 1).