A bunch of questions regarding radially magetized ring magnet.

[Magluvin]

Ive looked for radially magnetized rings and only found these so far.

You would think they could magnetize a ring radially just by having one part of the magnetizing core in the inner radius and the other end of the magnetizing core on the outer radius. But so far i only see pies. magpies.

https://supermagnetman.com/collections/neodymium/products/rr0100n?variant=11410371011

https://supermagnetman.com/collections/neodymium/products/rr0090n?variant=11410370819

Mags

[gyulasun]

Hey Mags,

Manufacturing radially magnetized rings has come to reality it seems.
Check these links from my earlier posts above:

https://www.alibaba.com/showroom/radial-magnetization-ring-magnet.html

http://www.materialhandlingzone.biz/product/aomag-uni-pole-radial-oriented-magnetization-neodymium-large-ring-magnets-diametrically-magnetized-od-70-x-id-62-x-20mm/

Gyula

[PolaczekCebulaczek]

gyulasun ok I understand now, thank you for better explanation, you are right about repulsion however if the ring is wide enough there should be no magnetism in the center because filed lines wont reach that far?

and my last stupid question, how such magnet can be used as generator? I have one (from speaker) and only when I move coil (coil is inside the ring in vertical position) or magnet up and down then current is generated, is there any other method ?

[gyulasun]

gyulasun ok I understand now, thank you for better explanation, you are right about repulsion however
if the ring is wide enough there should be no magnetism in the center because filed lines wont reach that far?

What do you mean on wide?
IF you mean that the inner diameter of a radially magnetized ring magnet is high enough, then yes
the magnetic field strength should be at a very low level in the very center axis line of the ring.
IF you mean something else on wide then I do not understand your question, try to put it otherwise.

and my last stupid question, how such magnet can be used as generator? I have one (from speaker)
and only when I move coil (coil is inside the ring in vertical position) or magnet up and down
then current is generated, is there any other method ?

Sorry to ask but are you sure your speaker magnet is magnetized radially? 
Because most speaker magnets are magnetized through their thickness i.e. axially:
one of their flat surfaces is say North and the other flat surface is the South pole.

This would explain your current induction in a coil moved axially through the center line of the your magnet.
If your ring magnet would be indeed radially magnetized, the induction would be at a minimum level
when you move a coil in it as you described. I am not saying there would be no induction in it but it would be
rather small compared to a similar sized and strong ring magnet magnetized axially like most speaker magnets.

Is your speaker magnet made of ferrite i.e. ceramic? By the way, you can check very easily how the poles
are made for your speaker magnet by a compass. Did you check it?  Is your speaker magnet magnetized
radially indeed like your drawing shows for a radial ring in your first post above.
In attachment below I included an axially and a radially magnetized ring magnet drawing.

Of course I am not saying your speaker magnet cannot be a radially magnetized ring magnet, in this case
you have to find the best coil-ring magnets arrangement to utilize it in a generator.
I think however that with multipole radial ring magnets you could get higher output
versus an unipole one of same size and strength.

Gyula

[PolaczekCebulaczek]

Sorry to ask but are you sure your speaker magnet is magnetized radially?
Because most speaker magnets are magnetized through their thickness i.e. axially:
one of their flat surfaces is say North and the other flat surface is the South pole.

You are right, I just did some better tests and I found that my magnet is magnetized axially

What do you mean on wide?

yes by wide I meant inner diameter, big hole.

IF you mean that the inner diameter of a radially magnetized ring magnet is high enough, then yes
the magnetic field strength should be at a very low level in the very center axis line of the ring.

yet compass needle(that can't reach magnet field lines would still point to earth pole?

I will buy some magnets online meanwhile can you tell me which of (7) induction methods would generate current when coil or magnet rotate.(I know that some of the configurations have 0 difference between then when we consider induction law but I just want to be 100% sure)