I have wanted to make an electric motor from scratch for quite a while now. But instead of just making a motor and hooking it to something like a fan I had an idea. What if the motor was integrated into the fan? I tossed around some ideas putting coils on a propeller blade and got hung up on making the brushes and commentators. I finally decided on doing a squirrel cage fan or if you want to get all scientifical a Centrifugal fan http://en.wikipedia.org/wiki/Centrifugal_fan.
With a bit of magic (sure come call it 3D printing) here is the rotor/fan wheel assembled with 30 turns of magnet wire wrapped longitudinal around each one making a total of 10 coils.
assembled rotor
assembled rotor
Dab of hot glue to hold the coil in place
My plan for the commentators and brushes did not quite work out (this is prototyping after all) so I decided to redesign it and make it bigger and glue it on for now. I will reprint it in one piece once I get the design squared away.
close up of failed commentator design
close up of failed commentator design
new design for commentator/ brushes design
new design for commentator/ brushes design
Moving on to the all-important housing which I am still designing. I got the basic shape but I am still thinking about how to design the brushes mount and still print the thing in just two halves. Here is the basic shape I am looking at more to follow once I finalize the design and print it out.
begining of housing design