A Comparison Study on Performances of Four Types of Oil Lubricated Hydrodynamic Thrust Bearings for Hard Disk Drive Spindles.

Abstract

In this paper, we numerically analyzed the static and dynamic performances of herringbone thrust bearing, step-pocket thrust bearing, taper-pocket thrust bearing and taper-fiat thrust bearing. The optimal values of design parameters of each type of thrust bearing in terms of both maximum axial stiffness (kzz) and maximum axial stiffness to friction torque (T) ratio (kzz/T) and bearing performances in both cases are calculated. We compared their optimal performances in terms of application conditions for a hard disk spindle. It is found that step-pocket thrust bearing and taper-pocket thrust bearing are obviously superior to herringbone thrust bearing and taper-fiat thrust bearing with respect to both maximum kzz and maximum kzz/T. We also found that the dams of thrust bearings with pockets play a great role in improving the bearing performances. It was made clear that taper-pocket thrust bearing and taper fiat thrust bearing have much larger maximum load capacity than pocket thrust bearing and herringbone thrust bearing.