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Toleracing of center distance with internal gear

  1. Jul 26, 2010 #1
    Hi all,
    first to say sorry if the question is repeated second time
    I've order a couple of internal gears from Rollix as picture below:
    [PLAIN]http://img155.imageshack.us/img155/5996/centerdistance2.jpg [Broken]
    The calculation from them for internal gears with center distance C=331.494 (mm)
    Backslash at center distance maxi: 0.98 (mm)
    Backslash at center distance mini: 0.53 (mm)
    module of bearing & pinion: m=10
    number of teeth: bearing=79, pinion=13
    pitch dia: bearing= 790, pinion=130
    The trouble now i'm facing is chosing tolerancing grade of center distance on bores to fit with shaft of pinion & bearing, more illustration on picture below:
    [PLAIN]http://img293.imageshack.us/img293/3594/74496622.jpg [Broken]
    Does any one know which of standard can be used to look up or formular to calculate the tolerancing grade of center distance in this case pls give me a help :redface:
    Thanks a lot for your reading this asking
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Jul 27, 2010 #2
    The pitch diameters should be tangential.
    Use that diameter to lay out your centers for the bearings and shafts.
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