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[on:]

Inside one..



What if the magnets were removed and replaced with electro magnets
instead...

Q1 Feasible?
Q2 providing it has no drastic flaws in this idea.... would that be less or more efficient?

[Reply #1 on:]

I don't see any permanent magnets in that photo, I only see the electromagnets (stator).

[Reply #2 on:]

Q1 Feasible?
Q2 providing it has no drastic flaws in this idea.... would that be less or more efficient?

a) No advantage over simply making those coils bigger.

b) How will you connect the electromagnets to a rotating thing? Brushes...?

[Reply #3 on:]

The permanent magnets(*) spin round with the fan, replacing them with electromagnets would require slip-rings....

(*) often in these small fan motors the magnets are actually a single strip of rubberised ferrite material inside the rotor bell
and magnetised with a repeating pattern of N-S-N-S poles.

The whole point of a brushless motor is to avoid the problems with having to conduct current to a spinning armature
via slip-ring or commutator - one less thing to wear out.

[Reply #4 on:]

Probably make a good motor though.. If you used the rubberized Ferrite magnets the torque might be somewhat low...

Doc

[Reply #5 on:]

The pic on this page shows the arrangement of magnetisation in a typical small brushless motor:
http://www.youritronics.com/implementing-a-brushless-dc-motor-controller/

[Reply #6 on:]

If you did this you would be making a brushed motor.
Yours Simon M.