Study of flow characteristics of lubricant in spiral groove bearings by the fluorescent method©

The hard disk drive spindle is one of the critical mechanical components in hard disk drives (HDDs). It has great influence on overall performance, including track density, data transfer rate, energy consumption and noise, etc. Nowadays, HDDs with higher density and speed, larger capacity and smaller size are under active development. This requires that HDD spindles have fast rotating speed, excellent accuracy and small size. However, ball bearing spindles, which are widely used in current HDDs, cannot meet these requirements. HDD spindles supported by oil-lubricated spiral groove bearings are considered to be a candidate to replace ball bearing spindles. There is no oil supply device in the bearing, and the flow characteristics of the lubricant in the bearing have a great effect on the performance of the spindle. In this paper, the fluorescent method is used to study the flo w characteristics of the lubricant in a spiral groove bearing. The establishment and recovery of the lubricant film during start/stop of the spindle are observed. The effects of working conditions on the thickness and distribution of the lubricant film are investigated. The influence of oil supply on the performance of the bearing is also studied.