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Converting Rotational Motion to Pendulum-Like Oscillation

  1. May 7, 2016 #1

    I am trying to create a mechanism that will allow for a motor to power a pendulum-like motion (but not an actual pendulum), back and forth. As shown in the picture, I need 180 degrees of rotation about the swinging part. I have researched escapement, but I need this design not to rely on gravity and to move much faster than I imagine the anchor escapement works. Ideally, such a mechanism would minimize the loss of torque on the output gear, so that I can use this oscillating motion to accomplish other tasks in my application.

    I would appreciate any help you can provide!

    Attached Files:

  2. jcsd
  3. May 7, 2016 #2

    Simon Bridge

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    There are lots of ways to do this - you know how to turn back-and-forth motion into circular motion ... this is just going the other way.
  4. May 7, 2016 #3
    Could you please provide an example?

    I'm not sure if it's clear in my drawing, but the green part is intended to rotate, not slide linearly. I could easily come up with mechanisms that convert linear to rotational or vice versa, but my problem is achieving a back-and-forth rotational motion to power another mechanism.

    I would really appreciate an example name or reference site! Thank you!
  5. May 7, 2016 #4

    Simon Bridge

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    A reciprocating motor turns back-and-forth motion into rotating motion.

    Now: none of us are going to present you with a design - this is what you pay engineers for.
    What we can do is attempt to match your existing knowledge with a direction for you to do your own research, maybe some trial and error.

    Imagine your green wheel has a peg sticking out of it ... that peg can fit into a groove in a rod. If one end of the rod is fixed to a pivot, then, as the wheel turns, the rod is forces to swing back and forth.

    This won't give you the full 180 ... but you can put a section of toothed gear on the swinging end and use that to drive another cog that your pendulum arm is fixed to.

    This is not actually a pendulum - it is a motor that waves a rod back and forth.
    If you prefer to have a free swinging pendulum that can be driven by a motor, that is a different design.
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