Patent ID: 6922309

Claim:
A spindle motor comprising: a stator including: a stator plate; a fixed shaft secured to said stator plate; a bearing secured to said fixed shaft; and a coil secured to said stator plate about said fixed shaft; and a rotor adapted for being rotated relative to said stator, said rotor including: a turntable that carries and secures a disc-shaped recording medium and adapted for being rotated relative to said fixed shaft via said bearing; a first ring-shaped magnet secured to said turntable and positioned inwardly of said coil about said fixed shaft; and a second ring-shared magnet secured to said turntable and positioned outwardly of said coil about said fixed shaft; said rotor being rotated relative to said stator about said fixed shaft by a first magnetic field generated in said coil by a current and a second magnetic field produced between said first and second magnets; wherein said bearing includes a first sleeve secured to the outer peripheral surface of said fixed shaft, a first flange secured to one end of said first sleeve, a second flange secured to the opposite end of said first sleeve, and a second sleeve securing said first magnet to said turntable and said second sleeve kept in contact with said first sleeve, said first flange and said second flange; and wherein herringbone grooves are formed in a surface of said first sleeve that contacts said second sleeve, a surface of said first flange that contacts said second sleeve, and a surface of said second flange that contacts said second sleeve, and wherein oil is applied to a first space between said second sleeve and the surface of the first sleeve, a second space between said second sleeve and the surface of the first flange, and a third space between said second sleeve and the surface of the second flange.