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:
Oct. 20, 2015
Filed:
Aug. 13, 2014
Nidec Corporation, Kyoto, JP;
Nidec Corporation, Kyoto, JP;
Abstract
A spindle motor includes a stationary portion with a shaft, a circular plate portion, a wall portion, and a plate portion. The plate portion has a flat plate portion and an annular convex portion. The sleeve includes an annular portion, an outer side cylindrical portion, and an inner side cylindrical portion. The inner side cylindrical portion and an upper radial dynamic pressure groove array are superimposed in a radial direction. The upper radial dynamic pressure groove array includes a plurality of upper spiral grooves that is inclined in one direction with respect to an axial direction and a plurality of lower spiral grooves that is inclined in another direction opposite to the one direction. A lower end of the upper spiral grooves is positioned farther on an upper side than an upper surface of the annular portion.