Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations waross on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

Search results for query: *

  • Users: JRCD
  • Order by date
  1. JRCD

    Fellows Stub Tooth, 9 teeth on a 10 tooth blank? Help..

    There are two questions in your proposed case. 1) The meaning of Fellows stub – tooth system For example for DP 8/10: a- use DP 8 for pitch diameter calculation d = N / DP = 9 / 8 = 1.125 " b- use DP 10 for addendum and dedendum calculation addendum = a = 1 / DP = 1 / 10 = 0.1”...
  2. JRCD

    worm drive backlash quantification

    EnglishMuffin I would like to send more comments. For backlash reduction, split worm gears are as good as two worms axially adjusted. In fact split worm gears are more compact and cheaper, but the unique drawback is the load capacity reduction unless the design provides larger width worm...
  3. JRCD

    cycloid gears

    didear Take a look at British Standard 978: Part I to III: 1952 (UDC 621.833:681-2), GEARS FOR INSTRUMENTS AND CLOCKWORK MECHANISMS. Part 2 is about Cycloidal Type Gears.
  4. JRCD

    worm drive backlash quantification

    EnglishMuffin Thanks for yours comments. I agree with you all-in.
  5. JRCD

    worm drive backlash quantification

    Involute (Aug 25): Really with splitting worm gear only half the tooth is in full contact. In my opinion the best method for backlash reduction is that using two worms, one at least axially adjusted. Backlash reduction by center distance decrease is not good solution. Firstly because put in...
  6. JRCD

    worm drive backlash quantification

    EnglishMuffin: Thank you for comments. Slice: I come again to the backlash subject. _ Why is backlash necessary? Backlash is necessary to supersede: a) the worst combination of gear meshing tolerances (including assembly center distance) and errors; b) the operational strain deformations; c)...
  7. JRCD

    worm drive backlash quantification

    Single and double enveloping worm gearing must run at the design center distance. To fix the backlash I suggest sliced and adjustable worm wheel or two axial adjusted worm gears, usually positioned 90 degrees apart (as used in table drive of some gears hobbing machines). Small backlash demand...
  8. JRCD

    ISO TR 4467

    Ester a] 0,03 is the right factor for expression x = 0,3 [30 - z]. b] Okay, for z=11 result x1 = 0,57. c] The preliminary [arbitrad] coefficient of profile shift can be accepted only with the knowledge of all requirements of power transmission and after the end of all calculation.You can adopt...
  9. JRCD

    ISO TR 4467

    Sorry, this subject is so extensive that I can’t give here a full development. You will find below only one preliminary example for external cylindrical gear drive design. -------I------- First of all start with estimated or imposed values for m...
  10. JRCD

    ISO TR 4467

    Your quiz is very important. You can buy the ISO/TR 4467:1982 standard directly of ISO (www.iso.ch/) or via AGMA (www.agma.org/). Also take a look at AGMA 901-A92 (R1997) and AGMA 913-A98 standards. During the XIX century gears were manufactured with profiling tools at milling and...
  11. JRCD

    Spur gear excessive wear in harsh environment

    Gears are running at very low speed for significant abrasive wear. I believe more at an overload or tip edge cutting wear, which will be aggravated by eventual hydrogen embrittlement caused by the gears plating. After plating gears must be backed to mend this. Hydrogen embrittlement deleterious...
  12. JRCD

    Spur gear excessive wear in harsh environment

    JRCD For good evaluation of gears teeth surfaces deterioration will be desired photos of teeth surfaces, in addition to gears lateral view. Within limits of available data: 1- Teeth surfaces are very worn in one side, but the opposed side is in good conditions, so gears life will be doubled...
Back
Top