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:
Mar. 30, 1993
Filed:
Dec. 02, 1991
Yumiko Noda, Kanagawa, JP;
Ichiro Kamiya, Tokyo, JP;
Manabu Toshimitsu, Kanagawa, JP;
Yoshio Sato, Kanagawa, JP;
Ryoichi Shinjo, Kanagawa, JP;
Ebara Corporation, Tokyo, JP;
Abstract
A ceramic hydrodynamic bearing used as a radial or a thrust bearing in a spindle motor for a hard disk driver. The bearing includes a ceramic bearing base having hydrodynamic pressure generating grooves. A sliding surface of the bearing base is irradiated with an energy beam with a high energy density to remove said material, thereby forming hydrodynamic pressure generating groove, and at the same time the grooves are coated with a modification layer that is formed by melting the ceramic material that constitutes said ceramic bearing base with the energy beam and by solidifying said ceramic bearing base.