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:
Apr. 17, 1984
Filed:
Aug. 26, 1982
Ryoji Yamaguchi, Tokyo, JP;
Tokyo Shibaura Denki Kabushiki Kaisha, Kawasaki, JP;
Abstract
In a motor unit, a motor shaft is supported by a pair of journal bearings of a herringbone dynamic pressure type. A polygonal mirror is fixed to one end of the motor shaft, and a magnetic thrust bearing is arranged at the other end so that the motor shaft is suspended thereby. The magnetic thrust bearing is formed of ring-shaped first and second permanent magnets. The first permanent magnets are coaxially fixed to the motor shaft and each have one pole on their outer surfaces. The second permanent magnets are fixed to a motor housing, and have their inner surfaces opposed to the outer surfaces of the first permanent magnets. The inner surface of each second permanent magnet has a pole different from that of its corresponding first permanent magnet. The first and second permanent magnets attract one another so that the motor shaft is suspended by attraction.