| 摘要 |
PURPOSE:To improve the degree of freedom of coil winding as well as the cooling efficiency by a method wherein a plurality of magnetic poles, around which coils are wound, is projected radially while the base ends of respective magnetic poles are formed with a width narrower than the width at the tip ends thereof. CONSTITUTION:A plurality of magnetic poles 17, around which coils 14 are wound, is projected radially while respective magnetic poles 17 are formed so as to have a tapered configuration, in which the width at the base end thereof becomes narrower than the width at the tip end of the same. Accordingly, the coil 14 having multiple turns may be wound around the magnetic poles 17 as required. According to this method, the occupying ratio of the coil 14 may be reduced in accordance with the ventilating capacity of an axial flow fan whereby the temperature-rise of a stator 13 due to the heat generation in the coil 14 may be restricted efficiently. |
