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:
Dec. 08, 1998
Filed:
Apr. 15, 1997
Jian M Wang, Tigard, OR (US);
Leoi Sun, Tigard, OR (US);
Charles J Cheever, Beaverton, OR (US);
Frank A Gray, Portland, OR (US);
SAE Magnetics (H.K.) Ltd., San Jose, CA (US);
Abstract
A hydrodynamic spindle motor of the present invention may include a shaft having a thrust bearing plate, an insert surrounding the shaft above the thrust bearing plate, and a sleeve surrounding the shaft below the thrust bearing plate. In one embodiment the thrust bearing plate is substantially centrally positioned along the longitudinal axis of the shaft. Preferably either the shaft has annular skewed herringbone shaft grooves or, alternatively, the insert has annular skewed herringbone insert grooves and the sleeve has annular skewed herringbone sleeve grooves. A set of circulation channels above the thrust bearing plate and a set of circulation channels below the thrust bearing plate preferably cross a shaft bore to allow for flow of lubricating fluid. A face seal may be formed between the lower radial cap surface of an end cap and an upper radial insert surface of the insert. The face seal may be used to form a capillary seal when the motor is in a static state and a pumping seal when the motor is in a dynamic state. The face pattern, in one embodiment, has a first annular zone adjacent the shaft, a middle annular groove, and a second annular zone.