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Rotating Electrical Wires

  1. Sep 20, 2013 #1
    I don't have extensive knowledge of electrical engineering so I need a little help.

    I want to make an electrical connection, but with one small hurdle. One wire must be stationary, and the other must be allowed to rotate. How would you guys go about solving this problem?

    My first thought was some sort of bearing. I've done a little research and found that there are some conductive bearings out there, but I would have no idea where to find a good one. Does anybody have any insight on this type of thing?

    Also, if any body has other ideas, please teach me!
  2. jcsd
  3. Sep 20, 2013 #2


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  4. Sep 20, 2013 #3
    based on what type of connection you are using this can be split ring (dc supply) or slip ring (ac supply)
  5. Sep 21, 2013 #4


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    If the voltage is less than 48V then you could make your slip rings from the brushes and rings of a disused automotive alternator.
  6. Sep 22, 2013 #5
    Hello kld15

    Google "Mercotac" They have all kinds of slip ring type connectors.
    The Leslie loudspeaker company used connectors like that to connect their rotating loudspeakers.

    Somewhere I've seen a low cost rotatable connector for telephone cables, to prevent twisting.


  7. Sep 22, 2013 #6

    jim hardy

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    Take apart an old car alternator and study the slip=rings & brushes.

    Don't re-invent the wheel - it's no shame to copy and adapt to your needs.
  8. Sep 22, 2013 #7
    About reinventing the wheel

    Remarks like that always get to me.
    I looked at all the posts and noone seems to suggest to reinvent anything.
    Every time I heard that remark in the past, it was used as a put-down.

    Besides, the invention of the wheel wasn't that great of an achievement until someone cut its corners off.

  9. Sep 23, 2013 #8

    jim hardy

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    But that has nothing to do with the op's question, which was:
  10. Sep 23, 2013 #9


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    Most steel ball bearings are conductive. I have some problems imagine your idea. Is it so that the stationary wire is connected to the center of this bearing while the rotating wires are connected to the outer part of the same bearing, and looped back somehow to the other end of the stationary wire?

  11. Sep 23, 2013 #10


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    Why? This time it was made 'helpfully'(as is normal for Jim :approve:) so there is no need for offence - and even less for vicarious offence). Start from where others have left off and, if by then, you have become an expert, you may improve on things. Engineering very seldom starts from square one - it's not an intuitive subject and relies on experience and incremental advances.
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