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Homework Help: Gear Problems

  1. Sep 16, 2012 #1
    1. The problem statement, all variables and given/known data
    A belt conveyor with a 1-foot diameter is driven by an electric motor. The conveyor must travel at 300 linear feet per minute while the motor turns at 1760 RPM. Design a gear train to connect the motor and conveyor and choose gears from McMaster-Carr.

    2. Relevant equations

    3. The attempt at a solution
    I calculated the RPM of the conveyor to be 95.5 RPM. I thought the simplest design would be if there was a compound gear on the shaft of the conveyor and the shaft of the electric motor, giving a simple two gear design. However, the calculated gear ratio is 18.4 and I cannot find two gears on the McMaster-Carr website that would give me that gear ratio. I read somewhere that between two spur gears the highest gear ratio is usually 10:1. I don't think a worm gear applies because that is for converting a high speed to a very low speed. Is that correct, or is 95.5 RPM sufficiently slow?
  2. jcsd
  3. Sep 16, 2012 #2


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    Have you considered 3 gears?

    Looks possible and keeps each stage <10:1

    PS I haven't actually checked the web site to see if the right gears exist.
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