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:
Jan. 22, 2008
Filed:
Aug. 21, 2002
Thomas Strothmann, Wallenhorst, DE;
Thomas Strothmann, Wallenhorst, DE;
Invacare Corporation, Elyria, OH (US);
Abstract
A multi pole electrical machine includes an armature and a stator. The armature is movable in a direction of armature motion with regard to said stator and includes armature pole pairs. These armature pole pairs follow each other in the direction of armature motion. Each armature pole pair corresponds to one magnetic period. The stator includes a differing fixed number of stator poles per armature pole pair to reduce a cogging force of the electrical machine. An arrangement of the stator poles, with regard to both electrical and magnetic aspects, includes at least two identical sub-arrangements of stator poles. These sub-arrangements of stator poles follow each other in the direction of armature motion. Each of the sub-arrangements of stator poles is associated with one or more armature pole pairs and includes more than three of stator poles.