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:
Jun. 15, 1993
Filed:
Aug. 01, 1991
Shinichi Ohi, Konan, JP;
Zexel Corporation, Tokyo, JP;
Abstract
A rotor magnet of the type including a plurality of circumferentially arranged magnets of alternately opposite polarities, wherein each of the magnets has a magnetizing pattern such that the magnetic force is minimum at predetermined portions near opposite ends of the magnet and gradually increases from the predetermined portions toward the center of the magnet and also from the predetermined portions toward the opposite ends of the magnet. With this magnetizing pattern, the rotor magnet has a substantially sinusoidal waveform-like magnetic flux density distribution pattern when the motor is rotating. As a consequence, the magnetic polarity changes smoothly and the motor can, therefore, operate at a low operation noise.