| 摘要 |
<p>25706 A simplified fan and brushless DC motor has a rotor with an annular permanent magnet that is magnetized in segments about its circumference and is associated with a wave-wound stator coil. Alternate circumferential segments of the magnet are oppositely polarized. Fan blades are located within the annular magnet. The wave-winding varies in position to present alternate magnetic fields opposite in direction to the rotor magnet outer surface to cause rotation thereof. The stator is ironless. The coil can have two bifilar windings alternately energized. A Hall device is, typically, employed for commutation along with suitable switching circuitry.</p> |
