| 摘要 |
PROBLEM TO BE SOLVED: To provide a spindle motor configured to reduce data writing error and data reading error of an optical disc fixed to a turn table by optimizing the size of a ball and the size of a yoke related to vibration to further reduce vibration of a rotor and the turn table.SOLUTION: A spindle motor 600 includes: a rotation shaft 100; a stator 200 including a coil 220 wound around a core 210 arranged around the rotation shaft; a rotor 300 including a yoke 310 coupled to the rotation shaft and including a magnet 350 arranged on an inner surface of the yoke to face the core; and a turn table 400 coupled to the rotor and provided with a groove 420 formed to accommodate a ball 410. The ratio Yr/Bd of the radius (Yr), defined by the distance between the center of the rotation shaft and an outer surface of the yoke, to the diameter Bd of the ball is in the range from 4.6 to 4.9 to reduce vibration of the rotor and the turn table. |
