Spindle motor for disk drives, has shaft including larger and smaller diameter sections with step containing hydrodynamic thrust and radial bearings formed in area of larger diameter section of shaft

摘要

The motor has a shaft (12) including larger and smaller diameter sections (38,48) with a step. The shaft is inserted into a central opening of a bearing sleeve (30). A bearing gap (40) is formed between the shaft and the bearing sleeve. A hydrodynamic thrust bearing is formed in the area of step and a hydrodynamic radial bearing is formed in the area of the larger diameter section of the shaft.