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. 28, 2000
Filed:
Aug. 05, 1998
Japan Servo Co., Ltd., Tokyo-to, JP;
Abstract
A multi-phase PM-type stepping motor comprising: a rotor constituted by a cylindrical permanent magnet with N poles and S poles magnetized alternately on an outer circumferential surface of the rotor; stator cores having teeth arranged in opposition to the N poles or the S poles on the outer circumferential surface of the rotor through a predetermined air gap; and excitation coils wound in the stator cores and for magnetizing the stator cores to thereby rotate the rotor; wherein, when the number of the stator cores is represented by n (n is an odd number not smaller than 5), and the magnetization pitch angle of the permanent magnet is represented by P, the teeth of the stator cores are shifted from each other by an angle of 2P/n.