PC Fan Generator

[geotron]

I've been experimenting with 3x6mm disc magnets lately,
and have found that connected along their diameters and
fixed to a PC fan, it makes quite an effective spinning
device.

http://www.youtube.com/watch?v=ASVbgBCq57s

The motor powering the fan is a 12VDC .18mA running at 5V.
All of the magnets - 12 of them in groups of two are high-
powered Neodymium permanent magnets, and weigh in at probably
3-5x that of the fan by itself.

The ratio of total magnet power between the motor itself and
the ones I have attached is far in excess towards the latter.

I'm thinking of the weight & flux-strength of the magnets in
the motor versus that of the Neodymium spinners. The ratio is
so far in excess I will not even attempt a guess.

What I'm thinking to accomplish with this small project is
somehow winding a bunch of copper wire into a shape or shapes
that will be able to pick up a charge from the spinning
North-South-North-South top surface of the device.

Honestly I do not know what other parts (diodes etc) that I
may be in need of to get it working properly, but the concept
of overunity I'm getting at is to spin a proportionately huge
amount of magnets around pickup coils with a tiny DC motor,
thereby amplifying the output.

The power input is 5V 74mA... and so far, my attempts at
using a single small coil for collection of charge have been
unsuccessful. What I did was hook the ends of a small 6mm
wide coil directly to the leads on my meter.

My working knowledge of electronics is not exceptional by any
means, so for now I must rely on the probablility that I'm
going about some stuff completely wrong.

Any and all help will be greatly appreciated!

[e2matrix]

Almost surprising the magnets stay in place.  I think you want to turn your coil 90° from the way you have it - i.e. the bottom of the coil (or top) should face the magnets instead of the side of the coil. 

[mscoffman]

All you can do is put bunches of coils around the motor's periphery.
You can use diodes preferably either germanium or Schotky
that have lower .2vdc pedestal voltages to put all the coils
in parallel boosting their current. Or you can run each diode
to a capacitor and stack up those boosting it's voltage or a little
of both.

Here's the rub, as you add coils and as you begin to put a load
resistor on them to extract electricity - you make the rotor
to harder to turn, ie you add a braking force to the rotor's
turning - As the motor becomes harder to turn that little
circuit inside the motor makes use of more input current or
else the motor slows down. The energy you use will almost
always be exactly balanced with what you get.
This is why generators are so extensively used...they can do
this balancing act with almost 100% efficiency. To see this
happening spread a few of the magnets around outside the
loaded rotor. The rotor should begin to cogging and the motor
using more energy. Exactly the same thing will happen with a
electrically loaded coil.

:S:MarkSCoffman

[geotron]

Ah... interesting.

Now what if one was to collect the back-EMF from
the motor, as well as the same from each coil,
and then rout all of it into the same location
as where the foward-current of the coils lead to?

Alternately, is there a way to collect back-EMF
from the motor and simply feed it back into the load,
thereby helping to speed up the fan?

[FatBird]

The inside magnets aren't doing anything because they are too far from the coil.

1.  All you need to do is to remove all of the magnets except the outermost 2 at both ends so it is balanced.

2.  AIM the CENTER of your coil (NOT the side of the coil) ABOVE the 2 rotating magnets.  The closer you hold the END of the coil to the magnets, the more voltage it will output.

3.  The output will be AC which is fine.  You should get enough output to light up a small flashlight bulb, or at least several LEDs in parallel.

.