Patent ID: 7090401
Filing Date: 2006-08-15
Classification: F16C

Abstract:
1. A fluid dynamic bearing comprising two surfaces rotatable with respect to each other, a lubricating medium located in a gap between the two surfaces during rotation of the bearing, wherein one of the surfaces is a shaft, and the other of the surfaces is a sleeve, the gap being defined between the outer surface of the shaft and the inner surface of the sleeve, and an interrupted and offset groove pattern formed on one of said two surfaces to distribute the lubricating medium over the surface of the bearing, the groove pattern comprising a plurality of grooves regularly spaced along a line representing a direction of rotation of the bearing, being characterized by a set of first segments and a set of second segments, wherein the set of first segments is offset relative to the set of second segments along the direction of rotation, and the first segments and the second segments are interrupted so that they are not continuous and wherein, during rotation, the lubricating medium is pumped in a substantially single direction by the first segment and the lubricating medium is pumped in a substantially single direction by the second segment.