Using a bearing as a conductor

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Hi,

I'm faced with a problem of powering a device on the non stationary side of a rotating joint.

I know the traditional solution is brushes, but would it be possible to use a bearing for this purpose? Would a bearing be always connected even while rotating?

I'm asuming a small ( 10-20mm outer diameter) ball bearing, but any type might do.

If this would work, would the bearing withstand say, 24V @ 1Amp? Or even 1.5Amp?

I'm going to do some experiments into this, but I'd like to know if anyone tried.

Thanks,

David

There are pointy haired bald people.
Time flies when you have a bad prescaler selected.

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Arcing of electricity can cause early bearing failure if conditions are correct/incorrect. This happens when welding equipment for instance.

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Gee, an arc adjacient a petroleum base lubricated bearing...

JC

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Closely coupled transformer cores?

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One of the issues … beyond arcing is the fact that, ideally, the concept of lubricant is to have a very thin sheen of lubricant coating the friction surface area. This is what prevents mechanical wear on the metal surfaces; theoretically, metal never touches metal. This is a problem for low current/voltage connections.

The other issue is that, when metal does touch metal, the transfer of electrons will cause metal degradation, first be the process of electrolysis, then by arcing. As the metal surfaces deteriorate, the bearing surfaces become rough, causing accelerated mechanical wear. And to boot, conduction of power will be diminished due to oxidation and contamination of the surfaces at the mechanical and electrical transfer point on the metal surface.

Did someone bring up the possibility of explosion or fire due to arcing in the presence of volatile chemical composition of the lubricant?

You can avoid reality, for a while.  But you can't avoid the consequences of reality! - C.W. Livingston

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http://www.electricstuff.co.uk/bbmotor.html
Better read this first!
This does actually work - many, many years ago I made such a device out of part of a junked disk drive. Having two ball races on the same shaft meant that I could take the power from one outer race through the bearings, through the shaft and out through the other bearing. Connected to a car battery(!) it was scarily fast.

Four legs good, two legs bad, three legs stable.

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One other thing: In the past when I wanted to do something similar I toyed with the idea of two motors, one to turn the assembly, and one at the other end of the shaft, with the motor body attached to the shaft and the motor rotor fixed to the outside world, so that the second motor acts asa generator.

Four legs good, two legs bad, three legs stable.

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Thought it would not be as simple as that. Thanks anyway guys!

There are pointy haired bald people.
Time flies when you have a bad prescaler selected.