| 摘要 |
PROBLEM TO BE SOLVED: To provide a brushless motor which stabilizes the reading of record by adjusting finely unbalance due to mutual collision of balancer balls and improving vibration absorption effect in the case of high speed rotation. SOLUTION: The lower side of a shaft 3 is supported rotatably by a bearing 2 fixed in the center of a stator core 1. A boss 4 is fixed to the upper tip side of the shaft, and there a turn table 5 is fixed. A cylindrical rotor yoke 6 whose bottom surface is opened is fixed to the boss 4 so as to surround the stator core 1. A balancer case 11 in which annular sliding space parts 10A, 10B accommodating a plurality of balancer balls 9A, 9B are formed is installed between the turn table 5 and the rotor yoke 6. The balancer balls 9A, 9B are accommodated in the sliding space parts 10A, 10B, respectively, and time difference is set until the balancer balls 9A, 9B stop. |
