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. 12, 1985
Filed:
Jul. 14, 1983
Tokyo Shibaura Denki Kabushiki Kaisha, Kawasaki, JP;
Abstract
In an electric motor unit, a fixed shaft extends within a motor housing. A plurality of parallel grooves are formed on the outer surface of the shaft, said grooves extending in parallel with the axis of the shaft. The shaft is detachably inserted into a hollow cylindrical spindle having a smooth inner surface such that a gap is provided between the outer surface of the shaft and the inner surface of the spindle. A dynamic pressure type radial bearing is formed by the grooved outer surface of the shaft and the smooth inner surface of the spindle to support the spindle in the radial direction. Stator ring magnets are fixed to the motor housing, with rotor ring magnets being fixed to the hollow cylindrical spindle. The inner surfaces of the stator ring magnets face the outer surfaces of the rotor ring magnets. These magnets are magnetized such that the mutually facing regions have opposite magnetic poles. The stator and rotor magnets form a magnetic thrust bearing; that is, the spindle is suspended by the attractive force generated between the magnets.