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:
Aug. 04, 2009
Filed:
Feb. 17, 2005
Hiromitsu Gotoh, Chiba, JP;
Kazuaki Oguchi, Chiba, JP;
Shinji Kinoshita, Chiba, JP;
Chihiro Tazawa, Chiba, JP;
Tomohiko Hayashi, Klong Luang, TH;
Hiromitsu Gotoh, Chiba, JP;
Kazuaki Oguchi, Chiba, JP;
Shinji Kinoshita, Chiba, JP;
Chihiro Tazawa, Chiba, JP;
Tomohiko Hayashi, Klong Luang, TH;
Seiko Instruments Inc., , JP;
Abstract
A fluid dynamic pressure bearing has an annular dynamic pressure generating face having a dynamic pressure generating groove, which draws a working fluid toward a midway position in the radial direction from the inside and outside of a thrust bearing plate in the radial direction when a shaft and a housing are rotated relative to each other. The dynamic pressure generating groove is provided on thickness direction end faces of the thrust bearing plate or on an inner surface of the housing, and an inner groove section is located on an inner peripheral side of the dynamic pressure generating face on the end faces and is recessed more than the dynamic pressure generating face in the thickness direction. A through-hole extends through the thrust bearing plate in the thickness direction so as to open to the dynamic pressure generating face, and a communicating cavity connects the opening portion of the through-hole and the inner groove section.