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Propeller and pulley

  1. Jun 29, 2011 #1
    Hi everyone!

    I want a string on a pulley to supply the power for the propeller, meaning i pull the string and the force is transformed to the propeller. I was wondering how could i create the system so that i can pull the string time after time and give the propeller more power (keeping somewhat of a constant speed and not just a one time pull) without stopping or disturbing its rotation.

    any ideas? thanks !
  2. jcsd
  3. Jun 29, 2011 #2


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    Gold Member

    A gear mechanism akin to a bicycle gear setup would accomplish this. Start off in low gear, once it gets up to speed, you switch gears on-the-fly.

    There are transmissions that use a continuous, fluid movement to gear up, rather than the chunkiness of gears. I can't remember what they're called. Instead of gears, they use a pulley over a sort of cone-shape. Some autos of yore had this.

    You could have a governor that fed back into the system so that, as the axle sped up, it would cause the pulley to move from the small end of the cone to the large end. Durr... technical terms escape me right now

    Here's a concept:
    [PLAIN]http://blog.arwdesigns.com/pics/CVT/CVT1.jpg [Broken]
    Last edited by a moderator: May 5, 2017
  4. Jun 29, 2011 #3
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