Abstract: An axial hydrodynamic bearing having two parts which are rotatable relative to each other about an axis of rotation comprises a first surface and a second surface facing the first surface. The first surface is formed with one or more patterns of bearing grooves which in the case of a rotation of the surfaces relative to each other act to build up pressure in a lubricant which is present between the surfaces during operation. A reservoir for the lubricant is present between the first surface and the second surface, one of the surfaces being formed with a pattern of feed grooves at the location of the reservior, which pattern is situated in an annular area which is concentric with the axis of rotation, to pump lubricant towards the pattern of bearing grooves operation.

Abstract: A bearing system comprises two hydrodynamic bearings by means of which two bodies having two cooperating bearing surfaces are supported for rotation relative to one another about an axis of rotation. At least one of the bearing surfaces of each of the bearings has patterns of helical grooves for building up pressure in a lubricant between the bearing surfaces during rotation. Further, the bearing system comprises a chamber which is arranged between the hydrodynamic bearings and which serves as a reservoir for an additional amount of lubricant. The chamber is bounded by two cylindrical wall portions. The two cylindrical wall portions off-set from each other to build up pressure in the lubricant in the chamber during rotation.