thijsco19
(thijsco19)
26
I think I understand what you are saying.
The fan blades themselves forms the rotor with the permanent magnets and a shaft.
That shaft fits inside the stator, probably with some sealed ballbearings, and is purely for alignment of the fan blades.
The stator has the electromagnets and the electronics. If you can make the electronics waterproof, coating them with resin for instance, you have made a waterproof fan.
The only challenge for the flashlight itself is to make the hole where the wires go through watertight.