Permanent Magnet Bearings

[Chris]

[WiLi]

sometime ago I was reading that there is a "scientific proof" for the fact that you cannot do a completely self-regulated magnetic bearing with permanent magnets alone. It needs at least one additional mechanical or regulated electronic means to fix ONE direction.

In contradiction to that I was thinking about it and had the idea to use a unipolar <+xxxx+> axle (just like this image with the arrow brackets) where the + signifies both North Pole ( or South).

Now take this axle and suspend it between two cups +<.......>+

like that:
+<<+xxxx+>>+

since the axle should have sharp pointed ends that should sit INSIDE equally sculptured cups from which they repell, my thought was that it should hover between the cups without mechanical contact.

This is what I would try out.

Maybe I am wrong with my idea?




Likewise I was thinking of an ALL Unipolar magnet. Of course it is not(?) possible to magnetize a ball with North outside and South inside, because you cannot put a counterpole into the ball for magnetization and remove it afterwords. But you could glue many smaller cone-like pieces together (all of them magnetized in the same direction) that in the end become a ball. Then you have a magnetic unipolar. (although it will NOT be easy to get them glued together. They will shrapnell apart as soon as you let go

Is there a possibility to "freeze" magnetism? I mean, change temperature so that a magnet becomes inactive, then glue it together and make it active again by returning to original temperature ?

Physicists wanted!


WiLi

[WiLi]

of course it is possible to have an all-permanent-magnetic suspension. The experiment with a super conductor and the hovering magnet shows it nicely. The super conductor forms an ideal counter magnet, exactly sculptured to the field of the PM and thus holds it into position mid air. The magnet can rotate around its own axle (at least as long as it is not a counductor by itself, otherwise eddy currents would have to be taken into consideration)

Maybe it is not possible to have a single ended magnetic suspension (like a coin hovering over a magnet) without a super conductor. But what about a two-ended magnetic suspension? (like with my first example above with the <xxxx> shaped axle?)

asks

WiLi

[Blox]

Hi Cris !

To fix a flywheel in mid air without friction, you could perhaps use
the princips from a levitron. ( See www.levitron.com ).
If the hoovering magnet is rotatet VERY fast, it will contain a HUGE
amount of energy.
This should be done under ( total ) vacuum, to avoid the air friction.
If there is placed cupper coil around the " flywheel " , you are
allmost there.


Blox

[dkmacmillan]

I think that it would be easy to do but probably expensive to do it right. The magnets would have to be 2 cylinders with 1 pole on the inside & 1 on the out. The cylinders would have to be opposites, if 1 cylinder had a north pole in the center, the other would have to have a south pole in its center, 2 more magnets to cap or plug 1 end of each cylinder, like WiLi's cups. The rotor shaft would have to be magnetized. If it works, putting the rotor shaft in the cylinder should be like pushing on a compressed gas piston. The sidewalls should be thick enough to keep the opposite pole far enough from the rotor shaft as possible. You might be able to do it cheaper with bar magnets, but I don't think it would work as well. I think balancing the moving parts would be a major issue as well.

[gregted]

Don't know if this helps but saw a story years ago on beyond 2000 that explained how a monorail with no wheels worked.

Someone found that highly polished alluminium acts like a mirror to magnetism so the rail for the monorail ( highly polished alluminium ), was simply repelling the electromagnets on the train, placed above and below the rail allowing the monorail to hover in place.

Maybe if your axle was polished alluminium placed inside a ring magnet, as a bearing, ( taken say from a magnetron inside a microwave ), this would hover in the centre!

Hope this helps.!!!

Keep free information free!!!

Greg.