"Mini Air Cooling Fan" part of the blades have a rubber magnet, it is there in front of magnetization work, magnetic. Also inside the rubber magnet surrounded by silicon steel, the second set of coils wound on silicon steel, when energized, the stator magnetic field will have four poles, silicon steel is due to the size of the head of the points, so the "Mini Air Cooling Fan"the shift is the shift from the bulk of the head, and a Hall sensor IC, control a set of circuits, the use of electromagnetic induction principle, IC turns two coils switching power supply, the use of two magnetic fields of same-sex attraction, repulsion heterosexual principle make "Mini Air Cooling Fan" operation