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. 25, 2014
Filed:
Oct. 12, 2012
Minebea Motor Manufacturing Corporation, Tokyo, JP;
Hiroshi Sano, Tokyo, JP;
Taketoshi Ohyashiki, Tokyo, JP;
Makoto Kinoshita, Tokyo, JP;
Katsutoshi Suzuki, Tokyo, JP;
Osamu Nakamura, Tokyo, JP;
Minebea Co., Ltd., Kitasaku-gun, JP;
Abstract
A stepping motor uses a low-cost ferrite magnet instead of an expensive rare-earth magnet. The stepping motor has characteristics equivalent or superior to those of a conventional stepping motor. The stepping motor is provided with a rotor, a stator yoke, and bearingsandwhich rotatably hold the rotorwith respect to the stator yoke. The rotorhas a columnar shape and has plural magnetic poles arranged in the circumferential direction of the outer circumferential surface. The stator yokehas an outer cylindrical portion and an inner circumferential portion which surrounds the rotorand which has plural first pole teeth and plural second pole teeth. The outer diameter 'd' of the rotorand the outer diameter 'D' of the stator yokeare set so that the ratio of “d/D” is greater than 0.6.