Patent ID: 8339731
Filing Date: 2012-12-25
Classification: B23H,F16C,G11B

Abstract:
1. A bearing assembly comprising: a sleeve comprising a first surface and a second surface, wherein said first surface is relatively larger than said second surface; and a shaft comprising a third surface and a fourth surface, wherein: said first surface, said second surface, said third surface, or said fourth surface is grooved, said first surface of said sleeve and said third surface of said shaft form a first fluid dynamic bearing, said second surface of said sleeve and said fourth surface of said shaft form a second fluid dynamic bearing, a fifth surface of said sleeve and a sixth surface of said shaft form a journal bearing disposed between said first fluid dynamic bearing and said second fluid dynamic bearing, said first fluid dynamic bearing is a small gap, high stiffness bearing, said second fluid dynamic bearing is a large gap, small stiffness bearing, and said first and second fluid dynamic bearings are operable to allow a relative axial movement between said sleeve and said shaft responsive to a relative tilting between said sleeve and said shaft.