Abstract: A fan motor includes base, stator and rotor units. The base unit includes a base plate with a shaft tube extending therefrom. The stator unit includes a stator core member, stator coils, and a circuit board. The stator core member has a metal core body that includes a central hub portion sleeved on the shaft tube, and a plurality of core-winding spokes extending from the central hub portion and having the stator coils wound thereon. The circuit board is coupled electrically to the stator coils. The rotor unit includes a drive shaft mounted rotatably in the shaft tube and extending outwardly of the shaft tube, a sensing ring having an inner ring surface that forms an annular clearance with end faces of the core-winding spokes, and a cover member having the drive shaft extending fixedly therethrough.

Abstract: A brushless dc motor applied to ac power in accordance with the present invention includes a conversion circuit. The conversion circuit includes a metallized film capacitor, a rectifier and a filter. The metallized film capacitor is serially connected to an ac power source, and adapted to supply with a rated ac voltage for the brushless de motor. The metallized film capacitor is further serially connected to the rectifier and the filter. The rectifier is converted an alternating current supplied from the metallized film capacitor into a direct current. The filter is filtered the direct current supplied from the rectifier and then sent to a motor drive circuit.

Abstract: An outer rotor structure for the ac fan mainly comprises a plurality of annular pole plates used to stack each other to form an outer rotor. Each of the pole plate includes an axial hole, a plurality of poles, at least one aligning member and a plurality of recessions. The aligning member is used to align the two adjacent pole plates for stacking so that the recessions of the pole plate are turned a slight angle in stacked relationship with those of the adjacent pole plate. The longitudinally connected recessions are formed a plurality of assembling members adapted to mount ends of metal blades therein at predetermined positions by welding.

Abstract: An outer rotor structure for an ac fan includes a plurality of annular pole plates used to stack on each other to form an outer rotor. Each of the pole plates includes an axial hole, a plurality of poles, at least one aligning member and a plurality of recessions. The aligning member is used to align two adjacent pole plates for stacking so that the recession of the pole plate are turned at a slight angle in stacked relationship with those of the adjacent pole plate. The longitudinally connected recessions form a plurality of assembling grooves adapted to mount ends of metal blades therein at predetermined positions by welding.