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Tesla coil for electromagnets

  1. Apr 3, 2011 #1
  2. jcsd
  3. Apr 3, 2011 #2
    Actually something doesn't have to work necessarily to receive a patent. For example an umbrella with a big hole in it could be patented if you wanted, it would be useless but you could patent practically any idea. What a patent is meant to do is to protect your intellectual property so that no one rips you off. Use and or function is in the eye of the beholder.

    I have no idea about this though. It seems that you could produce an electromagnetic force using this, whether the magnet would work very or better than the electromagnets of the time well I have no idea. early electromagnets were just essentially coils around a core though so?

    My guess is that this worked no better than the designs at the time, and so it never really took off or made him any money. But that would be a guess.

    I would of liked to of seen his death ray or his theory of gravity. :smile:
    Last edited: Apr 3, 2011
  4. Apr 3, 2011 #3
    I did not know that about patents of this sort, thanks.
  5. Apr 3, 2011 #4
    Yeah the primary use of a patent is to prevent plagiarism. It working is of no real consideration in most patents although if the government offered a patent out to tender to design say the next evolution in airforce combat, it would probably expect it to work. I've seen some pretty mental patents in my time for some pretty absurd things. :smile:

    Trouble is I suppose is how do you define useful. Something can work badly and still be useful somewhere. Equally someone somewhere might actually find a device that keeps your gerbil clean automatically very useful. Or self extending clown shoes: who knows?

    When the guy patented the hula hoop would you of told him it wasn't patentable. I would of said this is crazy its a fricking circle, why patent that? I wonder how much money he made from them though?
    Last edited: Apr 3, 2011
  6. Apr 6, 2011 #5
    Well it talks about it being a coil for electro-magnets. However, it later states that it is a self canceling coil. The double winding series connected magnetic canceling coils could be useful in products like grid connected power inverters used by the solar and wind industry on smaller home based units. The ability to cancel out it own magnetic field would in theory lessen interference with other electronics. The effects might be able to be applied to other wire types like trams mission lines, extension cords, electrical wiring in buildings to reduce exposure to high E. M. Fields. I do not know for sure I too have never seen his coil in action. I am just making some guesses from what I read in the patent.
  7. Apr 6, 2011 #6
    So is this saying that it is reducing Lenz's law?

    So this could be applied to transformers and motors theoretically too?

  8. Apr 6, 2011 #7
    If I've read it correctly, he's winding it to increase the self-capacitance so it behaves more like a transmission line at the working frequency than a pure inductance...

    I'm sorry, I can't think of a power-handling application as, IMHO, they're better done with separate coils and capacitors...

    FWIW, the configuration looks rather like 'passive' shop-tags, with a flat spiral designed to self-resonate near the security gate frequency...
  9. Apr 6, 2011 #8


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    That's the way I read the introduction page. The "new idea" seems to be that inductors have self-capacitance.

    Of course any EE student who does a course in RF circuits knows that now, but somebody had to think of if first.

    But it's often hard to be sure what Tesla was really thinking about, or if what he was thinking was actually right.
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