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Gearbox - transmission

  1. Jan 26, 2014 #1
    Hi guys,
    i would like to ask
    how do i increase my rpm using a gearbox (2,3,4 stages i don't mind)
    Input rpm 10 target output rpm 1500 and after that how can i calculate my torque?
  2. jcsd
  3. Jan 26, 2014 #2


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    Welcome to the forum.

    A speed increasing gearbox will probably need at least 3 stages to give a 150 x increase in RPM.
    There will be significant losses. The practical solution will be dependent on how much power output you require.
    What is the application? How much torque do you require at 1500 RPM?

    Power = torque * RPM

    There is possibly a single stage solution. A big shaft hydraulic pump driving a small shaft hydraulic motor where the pump has 150 times the displacement of the motor would achieve the required ratio.
  4. Jan 27, 2014 #3
    Föttinger clutch and the Torque converter come to mind. Porsche uses them in their SUV. But,what the OP is talking about is the 5th gear i.e overdrive.
    How the 'Turbine'(the output side) is made to spin faster than the flywheel side(input side) just by pumping-in more oil has always been a mystery(to me). Could you please clear that up? I know the structure and working principle of the hydraulic coupling. But,its overdrive characteristics are always left to merky insider info. People say its the KERS unit that kicks-in as the overdrive but I'm not really sure....
  5. Jan 27, 2014 #4


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    kotsios7 is asking about a 10 RPM = 1 rev per 6 seconds. That is a very big windmill or a water wheel.
    The 1500 RPM output speed is the same as an electric motor or generator.

    I was suggesting positive displacement hydraulic components.

    So, I don't think this thread is about a torque converter used in a vehicle.
    Questions about torque converters would probably be better under engineering/mechanical/automotive.
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