A hydrodynamic thrust bearing, particularly forming a part of a bearing system
for a rotary bearing of spindle motors utilized to power hard disk drives. The
thrust bearing includes at least one annular thrust plate and a counter bearing
corresponding to the thrust plate. The thrust plate is fixedly mounted on a shaft
rotatably supported by means of a radial bearing system. The thrust plate is arranged
on the shaft which is provided with an axial bore in the area where the thrust
plate is to be positioned. A spherical element fixing the thrust plate is pressed
into the axial bore. An outer diameter of the fixing element is greater than the
inner diameter of the axial bore. This type of press connection between the thrust
plate and the shaft allows comparatively thinner thrust plates to be used while
the performance of the thrust bearing remains the same or improves.