On optimal tooth profile modification for reduction of vibration and noise in spur gear pairs

The usefulness of deliberate modification of the tooth profile of a spur gear pair in reducing the level of vibration is studied. The severity of vibration and noise at different operating conditions have been measured by different metrics namely dynamic mesh force, dynamic tooth force, bearing force along line-of-action and off-line-of-action directions. The optimal modification of the tooth profile has been obtained by solving an optimization problem. Two methods, namely, a graphical method using contour plots and a semi-analytical method are presented for the said purpose. It is shown that if properly modified the vibration caused by geometrical errors like profile and pitch error can be reduced considerably.