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. 21, 2015
Filed:
May. 01, 2014
Nidec Corporation, Kyoto, JP;
Akinobu Sumiji, Kyoto, JP;
Nidec Corporation, Kyoto, JP;
Abstract
A spindle motor includes an upper bearing portion and a lower bearing portion each of which is inclined with respect to a central axis. The upper bearing portion includes an upper dynamic pressure generating groove defined in at least one of an upper outer circumferential surface of a shaft portion and an upper inner circumferential surface of a sleeve. The lower bearing portion includes a lower dynamic pressure generating groove defined in at least one of a lower outer circumferential surface of the shaft portion and a lower inner circumferential surface of the sleeve. The radial distance between a lower end portion of the upper dynamic pressure generating groove and the central axis is shorter than the radial distance between an upper end portion of the lower dynamic pressure generating groove and the central axis.