manster34
Mechanical
- Apr 26, 2001
- 2
Hello,
I've been looking for a practical way to determine the Lewis form factors "Y" for gears. This factor is defined as Y=(t^2 x Dp)/6l, where t= tooth thickness at critical bending stress points, DP= diametral pitch, l= tooth length as measured from t to top of gear tooth. Reputable gear literature suggests that to find t and l, to inscribe the gear tooth profile with a parabola, sometimes refered to as the stress parabola or Lewis parabola, tangent to the fillet radius. "t" is then found by measuring or calculating the distance across the tangency points. This is not as easy as it sounds, even with CAD or Solidmodeling software.
I have seen Y factors listed in books written by Buckingham and also in the AGMA information sheet 908-B89, however I would like to find a mathematical formula that I could put into an spreadsheet or into code.
Any suggestions?????
I've been looking for a practical way to determine the Lewis form factors "Y" for gears. This factor is defined as Y=(t^2 x Dp)/6l, where t= tooth thickness at critical bending stress points, DP= diametral pitch, l= tooth length as measured from t to top of gear tooth. Reputable gear literature suggests that to find t and l, to inscribe the gear tooth profile with a parabola, sometimes refered to as the stress parabola or Lewis parabola, tangent to the fillet radius. "t" is then found by measuring or calculating the distance across the tangency points. This is not as easy as it sounds, even with CAD or Solidmodeling software.
I have seen Y factors listed in books written by Buckingham and also in the AGMA information sheet 908-B89, however I would like to find a mathematical formula that I could put into an spreadsheet or into code.
Any suggestions?????