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Rod that slides up easily but slowly on way down

  1. Mar 12, 2014 #1
    I'm sort of stuck on a fiddly point at the moment. I'm trying to make a rod go upwards with ease but slow down on the way down (or even stop for a few seconds) when it has been completely let go by the pulling action (without any external energy). Anyone have any clues of how I can achieve this? Please ask me questions for additional details as I may have missed out vital points to include in my post.
    Last edited: Mar 12, 2014
  2. jcsd
  3. Mar 12, 2014 #2


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    Staff: Mentor

    Something like a ratchet?
  4. Mar 12, 2014 #3


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    Staff: Mentor

    Or a hydraulic shock absorber mechanism with 1-way valves for different damping rates for the up and down directions...?
  5. Mar 12, 2014 #4
    My first thought exactly
  6. Mar 13, 2014 #5


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    A hand bicycle pump come to mind.
  7. Mar 13, 2014 #6
    Thanks all, I've got a superb idea now, im going down the ratchet route although a hydraulic type pump was also a good idea but takes up a small amount of pull energy due to the tight conceals I would've had to put around it. Whereas with the ratchet design I'm thinking of there would be almost no extra energy needed and more crucially I can time it to execute an exact timed drop. Cheers all, this forum is the best :)
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