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Output of electric motor

  1. Aug 25, 2010 #1
    Hi all,

    I bought a small gearhead motor for a uni project, however the shaft is a strange shape. Round for the most part with a flat section. Not sure how I'd connect it to something? I could use glue I guess but would prefer a cleaner solution. Is there washers/couplers for these type of shafts that are easily available? Been searching online for a good hour with no luck.
     
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  3. Aug 25, 2010 #2

    Mech_Engineer

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    That is a very common shaft for a motor. The flat spot is to be used with a set-screw to hold the coupling in place whicle in motion.

    You can find a coupling that will work at http://www1.mscdirect.com/CGI/N2DRVSH?SISHNO=14263762&SISRCH=1&SIS0NO=1490332&SIT4NO=92383665".
     
    Last edited by a moderator: Apr 25, 2017
  4. Aug 25, 2010 #3
    Most of those components are more expensive than the motor...just to clarify, the motor's shaft is only ~2mm. Also, I didn't see any thing there that wasn't fully round.

    [PLAIN]http://www.jaycar.com.au/products_uploaded/productLarge_7971.jpg [Broken]
     
    Last edited by a moderator: May 4, 2017
  5. Aug 25, 2010 #4

    Mech_Engineer

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  6. Aug 25, 2010 #5
    Trying to attach it to a wooden axle. While I managed to get a D-ish shaped hole, the shaft grinded it round when the load got to heavy. Decided to just drill a flat screw through the axle onto the flat end of the shaft to keep it in place and it seems to be working well enough.
     
  7. Aug 25, 2010 #6

    Mech_Engineer

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    That's working because that's how it's supposed to be used. Making a D-shaped hole is expensive and unnecessary.
     
  8. Aug 25, 2010 #7
    Now I get what you were trying to say! So those small holes on the side of the couplers are for set (flat) screws?

    Thanks for the help.
     
  9. Aug 25, 2010 #8

    Mech_Engineer

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    Excactly!
     
  10. Aug 25, 2010 #9

    sophiecentaur

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    Flats on shafts can also be used in conjunction with 'Cotter Pins' like we used to have on all bicycle pedal cranks.
     
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