| dc.description.abstract | Fluid dynamic bearings(FDB) possess some characteristics of low noise, low friction, and shock resistance. In contrast to conventional ball bearings, FDBs have the advantages of high precision and an extended service life. Since FDBs use lubricant as a medium, the conventional herringbone grooves (HGJB) pump the lubricant in the inward direction during operation, i.e. toward the center of the bearing. Thus it has been known that HGJB increases the pressure within the journal, and improve the bearing performances. Therefore, the use of FDB has attracted particular interest for next-generation data storage applications.
However, the conventional HGJB has a chief drawback. The load capacity of the conventional HGJB decreases with decreasing dimension of the bearing, thus the spindle stiffness could be insufficient for miniaturized conventional HGJB. Nonetheless, some studies in the past have investigated the inner diameter of bearing at only Ø2 mm, and no study has analyzed the most miniature inner diameter of bearing at Ø0.6 mm. Therefore, aim in this study, the load capacity and side leakage of FDB of Ø0.6 mm inner diameter are analyzed respectively. In order to further improve the load capacity and provide greater spindle stiffness, this study will develop a newly designed multi-step elliptical groove journal bearing (Multi-step EGJB) and utilize numerical analysis program to find its optimal design parameters. In addition, this study also analyzes the performance of reversibl groove journal bearing (RGJB) using Comsol software. And this software can simulate different groove patterns.
Therefore, the aim of this study is to utilize numerical simulation program, Comsol software and Taguchi method to analyze the optimal design parameters of the HGJB, EGJB, and RGJB of Ø0.6 mm inner diameter. | en_US |