| 摘要 |
PURPOSE:To reduce the size of a fan motor by annularly mounting magnets on the outer periphery of a fan, arranging a plurality of stationary coils outside the magnet, and providing an annular yoke outside the coil, thereby eliminating a wasteful space. CONSTITUTION:Blades 3, 3... are radially mounted on a cylinder 2, at which a rotational shaft 1 is secured to the center, and circular permanent magnets 4 are secured to the outer periphery of the blades 3. A plurality of windows 5 are formed on the bottom of a bottomed cylindrical housing 6, an annular yoke 7 is mounted inside the side wall in the housing 6, stationary coils 8, 8..., are arranged inside the yoke, and bearings 9 are provided at the center of the bottom of the housing 6. Magnetic flux detecting Hall elements 14, 15 for detecting the magnetic flux are mounted at suitable positions on the inner surface of the yoke 7. |
