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Spur gears

  1. Jul 26, 2011 #1

    i would like some help on how to calculate the forces acting on each gear if the machine had 4

    for example gear 1 has a diameter of 100, gear 2 has 300, gear 3 has 133.34 and gear 4 has 266.66

    the machine is driven by an 80kW motor through a 2 stage gearbox having four spur gears. The input motor runs at 1850 rev/min and all gears have a pressure angle of 20 degrees

    if anyone can give me a helping hand with this it would be of most help thank you
  2. jcsd
  3. Jul 26, 2011 #2


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    This link might do what you need: Spur Gear Calculator v1.07 http://www.dakeng.com/spurgear.html
    It doesn't seem to accept pressure angles directly, but you should be able to derive what you need from the equations here: http://shopswarf.orconhosting.net.nz/spur.html [Broken]
    Last edited by a moderator: May 5, 2017
  4. Jul 27, 2011 #3
    thanks for the link however its not letting me download it
  5. Jul 27, 2011 #4


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    The full version installed OK for me. On trying it out, it's not as useful as I hoped, though, but perhaps I'm not using it right. Its help file is in an old format and I didn't bother to try to install the old helpfile reader. Googling "spur gear calcultor" gives some other results, but I'm not sure what you need.
    http://www.roymech.co.uk/Useful_Tables/Drive/Gears.html#Forces has some force formulas that should help once the other geometric factors are known.
    Last edited: Jul 27, 2011
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