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Transmission/Gear setup with constant output and variable input?

  1. Jan 8, 2005 #1
    is there such a thing as what's mentioned in the subject heading? Preferably a small device would be wanted...

  2. jcsd
  3. Jan 8, 2005 #2


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    What's meant by constant and variable? Speed? Torque?
  4. Jan 9, 2005 #3
    well speed primarily, but information on a device that has the constant/variable setup with torque would be useful also.
  5. Jan 9, 2005 #4


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    Yes there is. It is called a CSD, or Constant Speed Drive. They are used on jet engines. The main aircraft generators are driven off of the engines accessory gear drive. When the engine changes speeds due to operating requirements (i.e. takeoff vs cruise speed) the generator must maintain the same speed. That is where the CSD comes in. There are newer versions also called IDG for Integrated Drive Generator which is the same thing essentially excapet the generator and CSD are combined into one single unit. You can look these up for information on their principles of operation to give you ideas.

    What do you mean when you say "small size?"
  6. Jan 9, 2005 #5
    thanks for the help!

    and by small size i mean definitely not a jet engine lol, and more along the lines of a shoe box perhaps. but it would not be for an huge amount of torque.
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