Looking over videos on youTube, we've found a video by Carl Bugeja
and think it is very interesting. He presents a tiny PCB that are actually coils for a triple phase brushless motor. A brushless motor will create a magnetic field with the coils and push or drag some permanent magnets, in this case some neodynimum magnets. The change of polarity of the coils is made electronically. The board, as we can see has 6 coils on both sides of the PCB to increase the magnetic field created. In the middle it has space for a small bearing on with the top side of the motor will be placed.
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