| 摘要 |
PURPOSE:To provide a brushless motor which is suitable for the increase of a rate of speed of a hard disc and is right fit for a HDD of a portable-type equipment and has a high efficiency and an excellent shock resistance. CONSTITUTION:When current is caused to flow in a coreless coil 64 with the conduction direction being controlled, a magnetic field generated by the coreless coil 64 and a magnetic field by a magnet 66 act on each other and it makes a hub 58 rotate in the FA direction shown by an arrow (or in the opposite direction). A bearing holder 54 and the hub 58 are formed in a body and this united body also works as a yoke. Therefore, an inner space of the hub 58 is used quite effectively and the size can be reduced and bearing balls of a good shock resistance can be used. Since the careless coil 64 is used, there is no iron loss or cogging torque. Because of this reason, an efficient and high- speed operation can be available, less in consumption of current. |
