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. 06, 2001
Filed:
Apr. 10, 2000
Toshimi Abukawa, Gunma, JP;
Kazuo Ohnishi, Gunma, JP;
Yuji Takagai, Gunma, JP;
Sachio Hatori, Gunma, JP;
Kiyomichi Inoshita, Gunma, JP;
Japan Servo Co., Ltd., Tokyo, JP;
Abstract
An electric rotary machine has a concentrated winding stator and a rotor facing the stator with a gap therebetween. The stator has M number of stator magnetic poles extending in the radial direction from an annular yoke, pole pieces each extending in the circumferential direction of the rotor from the tip end of each of the stator magnetic poles, and windings wound around the stator magnetic poles. The rotor having a permanent magnet with P number magnetic poles, wherein P:M=6n−2:6n, or P:M=6n+2:6n, where n is an integer not less than 2, and the figure of each of the pole pieces is so determined that a gap formed between the pole piece and the rotor is increased going toward the both ends of the pole piece.