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[Nali2001]

Hi all, I might have some interesting idea:
An (relatively) easy to realize Hildenbrand style permanent magnet assisted magnet motor.
You might know that next to all washing machines have a motor with a core that can be easily adapted for this use. I think the pictures talk for themselves but just in case I will explain it a bit:

The plan is to make a 3 valve motor much like Hildenbrand has done only this time it is on a budget. So We use old washing machine motor cores. So you need 3 the same core. Might sound difficult but it?s not really so, a lot of brands use the same motors. These things can of course be bought new, but a better option is to go to your local recycle center or repair shop or whatever. There you will be able to scrap them out of old dumped washing machines for free (Or cheap at least.)

So now you have 3 cores, you remove the windings. Now on one side of each core you need to take out a part of the core for the magnet. You can use a metal mill, or go see some metal machinist and have them do it for you. (Mind the laminations)

On the other side of the core you need to wind a coil that should at a given input have the same strength as the permanent magnet. And preferably saturate the core section where it is wound around. So that it acts even more as a gate, to not allow the passage of any flux from the permanent magnet.

Next thing to do it construct some kind of precise rotor.

Now we connect all three valves to each other through a shaft. For far better torque results through the whole rotation of the system you want to advance each rotor 120 degrees relative to each other.
Of course you need to make some circuit that will pulse the coils, you could use opto switching, or maybe even a commutator or some other contact point based system. But I leave that up to you. Next to mechanical output you should be able you recover a good part of the back emf from the input coils. This can be done up to saturation.

So that all, I must say that there are far better rotor shapes possible than the one seen in the pictures. But one should look into variable or switched reluctance motors for more understanding of such a rotor arrangement.

Well maybe in inspires some to start a little project.
Thanks

[FredWalter]

On the other side of the core you need to wind a coil that should at a given input have the same strength as the permanent magnet. And preferably saturate the core section where it is wound around.

How do you figure out how much flux is required to saturate the core (and from this, figure out the best size/strength of permanent magnet to use)?

Once you have the right size/strength of permanent magnet, how do you calculate the wire size/number of turns/voltage/amperage so that the resulting electro-magnet will be the same strength as the permanent magnet?

Next thing to do it construct some kind of precise rotor.

Doesn't the rotor require magnets (whether permanent magnet or electromagnet) so that it will react to the flux through it, and rotate?

Of course you need to make some circuit that will pulse the coils, you could use opto switching, or maybe even a commutator or some other contact point based system.

Would what this guy is developing work here?

http://www.overunity.com/index.php/topic,2071.0.html

[Nali2001]

Hello there FredWalter.
Look mate I don't claim to have all the formula's to super precisely calculate the saturation levels but it can be found by trying the system out, and varying the input to the coil and monitor when it's performance it optimal. But this all is not that much of a problem. And if the coil is completely not able to saturate it at all, just wind another one, costs you a dollars of wire, and 30minutes to do so. Small price to pay, in my opinion. In my experiments with other systems I found that a given cross section of regular silicon laminated steel (from mots or stators) will be saturated, by a n42 magnet of the same cross section.
See the attached movie for an example.

And no you don't need magnets in the rotor. The rotation is coused by the combined flux of the coil and magnet wanting to pull the rotor in better alignment, and so couse rotation. But this principle of rotation is noting new or anything. The variable and switched reluctance motors have worked by the principle for decades. For more info look a google for example.
http://www.srdrives.com/technology.shtml
http://www.sovereign-publications.com/images/srdrives/picture1.jpg
http://www.simulation-research.com/sr/products/tesla/html/Image144.gif
http://images.google.nl/images?hl=nl&q=switched+reluctance&btnG=Afbeeldingen+zoeken&gbv=2

There would be many ways of powering these coils and should not be too hard to create for someone somewhat skilled in circuits.

[JackH]

Hello Nali2001,

Sorry but this design will not work to overunity.   I have allready tryed it.  To get the four times amplifaction the permanent magnet and the coil need to be on the same side.  Also there is not thick steel, you will over saturate the fields.  Also in my experiments with the magnet on one side, the rotor did not want to turn loose of the permanent magnet flux lines.  They would need to travel across over to the coil side to short out.    You can make a motor like this but do not expect it to be very efficient.  Don it.

Later,,,,,,,JackH

[wizkycho]

Hi Nail !

good thinking to use existing motors and "repair" them.
but this I think would not work

In this setup:
 If Core (rotor) is in 90-270 deg position and coil off there will be magnetic flux going thru Core from magnet (if air gap is small (should be)) - can not work that way.

maybe something else...

wiz

[wizkycho]

btw. Nail !

can You post here ziped fem file so I can make some analysis...
have some ideas ....

thanks

Wiz

[wizkycho]

Hi nail2001 !

this could work (simplified core) coil is between two magnets.

Wiz

[wizkycho]

wiz

[broli]

Magnetic transistor!!!

Wizkycho, Good eye on catching this thread, since I understand your idea I'm starting to understand others as well and they seem to have one thing in common. That is the use of a coil to reroute the magnetic field. This concept is easy and simple I hope it inspires others as well.

Edit: wizkycho, since I always find your sims a bit difficult to look at since they lack any solid colors, here's a contribution so others can instantly get what's what.

[gyulasun]

Hi Folks,

Seems very good!   

One notice:  I think there must a small air gap be left where the middle column touches the horizontal core so that

1) the returning flux could easier go back to the left and right side vertical colums

2) in the coils' off state the diagonal unlike poles could find it hard to see each other through the middle column.

Do you agree?

rgds,  Gyula

EDIT:  I'm affraid Lenz can still apply (dispite the small airgap), when you load the output coil (not shown) in the middle column