Fluid dynamic bearing system of spindle motor used for operating hard disk drive for rotary-driving magnetic storage disk, has asymmetrical-arranged radial bearing grooves towards which bearing fluid is predominantly promoted

摘要

The system has a shaft (12) that is arranged in a bearing bore of a bearing bush (10) relative to the bearing sleeve. The bearing surfaces are formed between bearing bush and the shaft and are filled with a bearing fluid bearing gap (14). The shaft is provided with several shaft sections (12a-12c) of different diameters. The fluid-dynamic radial bearings (16,18) are provided with the radial bearing grooves (16a,18a) that are asymmetrical. The bearing fluid in the bearing gap is predominantly promoted towards the radial bearing grooves of radial bearings.