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. 24, 2004
Filed:
Oct. 16, 2002
Masafumi Sakamoto, Gunma, JP;
Japan Servo Co., Ltd., Gunma, JP;
Abstract
A permanent magnet type rotary machine according to the present invention has a stator having an annular magnetic member and three, four, five or six stator magnetic poles ( ) extending radially from the annular magnetic member, windings ( ) of three, four or five phases, each wound around each of the stator magnetic poles ( ), two sets of rotors ( ) adjacent each other arranged in the axial direction and faced to the stator with an air gap therebetween, and two permanent magnets ( ) magnetized in the axial direction. Each of the stator magnetic poles ( ) has a plurality (Nr) of magnetic teeth at the tip end thereof, each set of the rotors ( ) consists of two rotor elements ( ), each having Nr pieces of small tooth on the outer peripheral surface thereof, each of two permanent magnets ( ) is held by the two rotor elements ( ) in each set of the rotor ( ), and the two rotor elements ( ) in each set of the rotor ( ) are deviated by ½ the pitch of the small rotor tooth from each other in the circumferential direction so that the small rotor teeth of adjacent rotor elements ( ) of two adjacent sets of the rotors ( ) are the same in polarity. Nr is 3n±1, 4n±1, or 6n±1 (where, n is a positive integer).