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:
May. 05, 1998
Filed:
Dec. 18, 1996
Jeco Co., Ltd., , JP;
Abstract
In a stepping motor, each of four integrally molded annular stators constituting two pairs has an annular plate having a central hole in which a magnet rotor is to be inserted, and pole teeth that form magnetic pole portions separated from the magnet rotor at a predetermined gap. The pole teeth of one annular stator of a given pair extend from the annular plate to be perpendicular to the other of the given pair, and are equidistantly arranged around the central hole to be shifted from the pole teeth of the other annular stator by a half pitch. Mounting holes are formed in each annular plate at predetermined spaces in the circumferential direction, and the mounting holes formed in the annular plates of given annular stators of different pairs that are arranged back to back are located at the same positions. Molded insulating films are formed on surfaces, which do not oppose the magnet rotor, of all the annular stators. The insulating films are coupled to each other through the mounting holes formed in the annular plates of the given annular stators. Excitation coils are wound on all the annular stators through the insulating films. A plate-like yoke has a major portion inserted between opposing surfaces of the annular plates adjacent to the outer circumferential surfaces of all the annular stators.