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An Inductive Charging Wheel for Free-Wheeling Strollers?

  1. Apr 27, 2015 #1
    Hello all,

    I am trying to come up with a design to have a free moving wheel create electricity using inductive charging... I am doing this project for one of the courses i am taking. I am little stumped on how i would go about designing this to create the maximum power. Do you guys have any suggestions?

    Thanks
     
  2. jcsd
  3. Apr 27, 2015 #2

    phinds

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    I'm not clear on what you are trying to do but from your title it sounds like you are trying to build a Perpetual Motion Machine. Are you?
     
  4. Apr 27, 2015 #3
    No, not really. I am looking to try to build a stroller that has the ability to charge you device. I want to wheels to generate the power using inductive charging. Would this be possible?
     
  5. Apr 27, 2015 #4

    phinds

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    I don't really know but it does not sound like the right approach at all. You should be looking at generators (little bitty ones) that are powered by the wheel turning.
     
  6. Apr 27, 2015 #5
    Yeah. I can do that with a DC motor. I can only do that with a wheel on an axle. I cannot do that with a free moving wheel on like a stroller
     
  7. Apr 27, 2015 #6

    phinds

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    Oh, now I see what you're getting at. Well if you are taking energy away to power something, no matter how you do it, the wheel won't be exactly "free wheeling" any more but if the power drain is not much, you won't likely feel much drag. I don't know how you would manage to do it, but I wouldn't be surprised if it were doable. You'd probably need to attach a super magnet to the wheel and have some sort of pickup on the undercarriage and then you'd need circuitry to handle the fact that the voltage will be quiescent most of the time and then peaking as the magnet goes past the pickup.
     
  8. Apr 27, 2015 #7
    makes sense. Thanks.
     
  9. Apr 27, 2015 #8

    berkeman

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    Have you seen the old bicycle headlight dynamos that had a small wheel that was held up against the bicycle tire to generate the electricity for the headlight? It made pedalling the bike harder, but you did not need to recharge your light every night. I'll post a pic if I can find one...

    I'll also edit your thread title to be more accurate for the question you are asking. You set off the Free Energy / Over Unity / Perpetual Motion Machine detectors with your current title... :smile:
     
  10. Apr 27, 2015 #9

    berkeman

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  11. Apr 27, 2015 #10

    sophiecentaur

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    The kind of dynamo that gets its power by friction against the tyre is convenient to mount on any bike (which is an advantage) but a far more efficient arrangement is the 'Dynohub' style of alternator that uses a static coil and strong permanent magnets mounted inside a cylindrical. This link is from a real enthusiast!!
     
  12. Apr 30, 2015 #11
    You can generate pulsed AC using perm. magnets embedded in the wheel with a stationary coil mounted to the frame.

    The output would mos probably need conditioning depending on application This would be good for a light, efficient, low power output. It is used in applications such as chain saws. Some early motor cycles used magnetos for ignition and lights. The early model T Fords used a magneto system.
     
  13. Apr 30, 2015 #12

    Baluncore

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    If the “inductive generator” has permanent magnets, then it must be sealed against the environment or it will collect magnetic material from the ground or soil.

    The weight of a generator can be reduced proportionally by increasing the RPM. A stroller wheel rotates so slowly that it will require a big generator if it is integrated, (with direct drive), into the wheel.
     
  14. Apr 30, 2015 #13

    sophiecentaur

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    If a dynohub works when walking along with a bicycle then, with the diameter wheels that a stroller has, there will be more than enough rotational speed.
    Keeping it clean could be a problem and it would need a 'blade' of some kind, to wipe away the accumulated nails and iron filings.
     
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