Question about interacting magnet fields
Question about interacting magnet fields
(OP)
Im an amatuer designer/inventor and have a question about the nature of magnets. I am currently working on a machine which may incorporate magnets into the design...
OK... i hope this makes sense.
Represented bellow are 3 disc magnets in a tube. Magnet 1 (|1NS|) and magnet 3 (|3SN|) are static. magnt 2 (|2SN|) is attached to magnet 3 via magnet attraction. S & N represent the polarity of the magnets (south and north respectively).
|1NS|.......|2SN|.|3SN|
A force is applied to magnet 2, breaking the connection between 3 & 2.
and propeling it towards 1.
<-----
|1NS|.|2SN|.......|3SN|
When this force has stopped, magnet 1 repels magnet 2 in the direction
of magnet 3 and is then reattached to magnet 3.
----->
1NS|.......|2SN|.|3SN|
In my machine, doing this !consistantly! for periods of time at rates of up to 20 times a second are essential to the function.
Question1 will the interacting magnetic fields gradualy decrease the strength of the magnets?
Question2 are there any undesired effects of moving a magnet in this manner back and forth
Thankyou for your time.
OK... i hope this makes sense.
Represented bellow are 3 disc magnets in a tube. Magnet 1 (|1NS|) and magnet 3 (|3SN|) are static. magnt 2 (|2SN|) is attached to magnet 3 via magnet attraction. S & N represent the polarity of the magnets (south and north respectively).
|1NS|.......|2SN|.|3SN|
A force is applied to magnet 2, breaking the connection between 3 & 2.
and propeling it towards 1.
<-----
|1NS|.|2SN|.......|3SN|
When this force has stopped, magnet 1 repels magnet 2 in the direction
of magnet 3 and is then reattached to magnet 3.
----->
1NS|.......|2SN|.|3SN|
In my machine, doing this !consistantly! for periods of time at rates of up to 20 times a second are essential to the function.
Question1 will the interacting magnetic fields gradualy decrease the strength of the magnets?
Question2 are there any undesired effects of moving a magnet in this manner back and forth
Thankyou for your time.





RE: Question about interacting magnet fields
The above page answers question 1, i beleive.
Consistancy is the key, though... can my above operation move at the same speed given the same force applied each time?
RE: Question about interacting magnet fields
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RE: Question about interacting magnet fields
Hard to say what's an undesired effect is without knowing what the heck the machine is.
You will be creating a time-varying magnetic field. This can induce currents in thick metal or metallic loops. It may also disrupt electronics.
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RE: Question about interacting magnet fields
I have now incorporated a mechanical stop into the design so that the magnets never actually touch also practical as i have chosen Neodymium magnets which are quite brittle. Would this stop any demagnetising from them slamming together?
"You will be creating a time-varying magnetic field. This can induce currents in thick metal or metallic loops. It may also disrupt electronics."
Ok... i had a gut feeling about this so the electronics are located as far away from the magnetic mechanism as possible... my device is mobile so out of curiosity is there a possibility of harnessing the electric currentfrom the time-varying magnetic field to charge a battery?
The rest of my device is constructed from brass and aluminium, strong magnets should have no effect on these materials, right?
Thanks for your time and knowledge
RE: Question about interacting magnet fields
You can nicely demonstrate this to yourself by dropping a magnet down the inside of a piece of copper water pipe. It will slow noticeably.
You could possibly harness the electricity but it will take you more energy to get it than you make.
Mike
RE: Question about interacting magnet fields
so the heat generated from eddy currents could effect the strenght of magnetism possibly causing a loss in consistancy of the operation?
The force that moves magnet 2 is pressurised air, so the air flow may offset any heating of brass and alluminium. The other option would be to not use brass and aluminium and use a strong plastic composite instead... but this could cause components to wear out quicker.
I had it pointed out to me that wrapping a copper coil around the tube which encases the magnets could be used to create an electrical charge which could be harnessed to charge a battery... is this so? and is it worthwhile?
RE: Question about interacting magnet fields
...wrapping a copper coil ...
Yes it could produce a current. Worthwhile is up to you and the application.
A flashlight is made that is charged in this manner.
Mike
RE: Question about interacting magnet fields
Thank you everyone for your help, i'm very grateful, with the advice given i've made several design changes and saved myself a lot of head-aches.
RE: Question about interacting magnet fields
Chuck