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. 25, 1992
Filed:
Aug. 08, 1990
Daisuke Konno, Kanagawa, JP;
Sachihiko Miwa, Kanagawa, JP;
Shunichi Aiyoshizawa, Tokyo, JP;
Kazuyuki Kasahara, Kanagawa, JP;
Yoshio Sato, Kanagawa, JP;
Kazuto Hirokawa, Kanagawa, JP;
Yumiko Noda, Kanagawa, JP;
Ebara Corporation, Tokyo, JP;
Abstract
A bearing structure suitable for a spindle motor or the like, which enables such a motor to rotate with minimal vibrations. The bearing structure comprises a stator including a support shaft which is disposed on a base, and a rotor which is rotatably disposed around the support shaft. A radial hydrodynamic bearing and a thrust hydrodynamic bearing are disposed between the stator and the rotor. The stator has the support shaft, a thrust plate and a radial cylindrical member which is concentric with the support shaft. The thrust plate is secured to an end surface of the radial cylindrical member. The support shaft extends through the centers of the radial cylindrical member and the thrust plate. The rotor has a radial sleeve. The radial hydrodynamic bearing is formed from the inner peripheral surface of the radial sleeve and the outer peripheral surface of the radial cylindrical member, which face each other and either of which is formed with herringbone-shaped grooves for generating dynamic pressure. The thrust hydrodynamic bearing is formed from an end surface of the radial sleeve and a sliding surface of the thrust plate, which face each other and either of which is formed with spiral grooves for generating dynamic pressure. A rolling bearing may be added in order to minimize the starting torque in the bearing structure.