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. 22, 2003
Filed:
Feb. 09, 2001
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
Provided is a durable spindle motor with a precise rotation but free from a shaft vibration, a decrease of rotation accuracy or a contact due to a swing during rotation. A shaft ( ) is inclined relative to a sleeve ( ) by an external biasing force, generating and then utilizing a hydrodynamic pressure generated during the rotation. The sleeve ( ) has a central cylindrical section (C) extending parallel to the axis and two tapered sections (A), (B) each connect(d with the cylindrical section (C) at its opposite ends and enlarged outwardly, so that a dynamic force is generated between the tapered sections (A), (B) and the shaft ( ). Preferably, an inclination of the tapered sections (A), (B) is identical to that of the shaft ( ), and lengths of the tapered sections (A), (B) is one fourth of that of the sleeve ( ). Similar advantages can be attained in an arrangement in which the sleeve ( ) is defined in the form of cylinder while the shaft ( ) is defined at its peripheral center with cylindrical section (c) and at its opposite ends with tapered sections (a), (b).