| 摘要 |
PURPOSE: A spindle motor is provided to prevent evaporation of oil by forming a fluid dynamic bearing between a shaft and a sleeve, to extend the length of a support unit for forming a labylinth sealing and to preserve a rotational property and the durability of a motor by preventing the evaporation of the oil. CONSTITUTION: A spindle motor includes a shaft, a sleeve (120), a rotor and a stator. The shaft includes a top thrust plate (111) in a top part and includes a bottom thrust plate (112) in a bottom part. The sleeve has a cylindrical shape having a void section in the center to be supported by the shaft in a rotatable manner. A hub (130) includes a cylindrical unit (131), a circular plate unit and a skirt unit. The circular plate unit is externally extended from the cylindrical unit which is fixed in an upper end part of the sleeve. The skirt unit is extended to a vertical lower direction from an edge of the circular plate unit. A base has a support unit (141) having a cylindrical shape in the center. The support unit is extended to be overlapped with the cylindrical unit leaving a small gap with the cylindrical unit of the hub and supports the sleeve using the void section formed in the center of the support unit. |
