Patent ID: 7541708

Claim:
A spindle motor comprising: a stator comprising a stator core having teeth; a wire wound around the teeth of the stator core; and a rotor comprising: a rotation support shaft, a rotor hub and a magnet, the rotor capable of being rotationally driven by a rotational magnetic field created when a current is applied to the wire, wherein the stator core comprises a laminated plurality of magnetic steel plates mounted to an outer periphery of a supporting part of the rotation support shaft of the rotor, the supporting part of the rotation support shaft comprises sintered metal containing a ferromagnetic material, and can be passed through a magnetic flux of the rotational magnetic field, a hydrodynamic bearing comprising an operating fluid filled between the rotation support shaft and the supporting part, and at least a portion of the supporting part of the rotation support shaft which comes into contact with the operating fluid is pore-sealed treated.