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:
Feb. 16, 2010
Filed:
Nov. 29, 2005
Rikuro Obara, Kitasaku-Gun, JP;
Tadashi Akahori, Kitasaku-Gun, JP;
Rikuro Obara, Kitasaku-Gun, JP;
Tadashi Akahori, Kitasaku-Gun, JP;
Minebea Co., Ltd., Kitasaku-gun, JP;
Abstract
A fluid dynamic pressure bearing device includes a shaft member () and a bearing member (), at least one of the shaft member or the bearing member being rotatable with respect to the other. A shaft member-side annular member () is fixed with respect to the shaft member. The shaft member-side annular member includes a large-diameter rim portion and a small-diameter outer circumferential surface portion. A bearing member-side annular member () is fixed with respect to the bearing member. The bearing member-side annular member includes an inner circumferential large-diameter step portion, and a small-diameter inner circumferential surface portion. A plurality of convex surface portions are formed either on a surface of the inner circumferential large-diameter step portion facing the large-diameter rim portion of the shaft member-side annular member, or on a surface of the large-diameter rim portion of the shaft member-side annular member facing a surface of the inner circumferential large-diameter step portion. A reflux groove () surrounds the convex surface portions.