Patent ID: 6848829

Claim:
A hydrodynamic bearing system for a spindle motor, said bearing system comprising: a shaft having an outer surface; a sleeve having an inner surface, one of said shaft and said sleeve being rotatable with respect to the other; and a lubricant circulating between said inner and outer surfaces, wherein a lubricant reservoir is defined by a recess in said shaft and said inner surface of said sleeve, wherein said reservoir is provided in the area of at least one opening of said sleeve, wherein said recess further comprises a first tapering transitional area and a second tapering transitional area, wherein contours of said tapering transitional areas form acute angles with the cutting plane of said shaft, wherein said first tapering transitional area is located inside said sleeve, wherein said second tapering transitional area is located outside said sleeve, and wherein said first tapering transitional area is inclined with respect to an axis of said shaft at a smaller angle than said second tapering transitional area.