Influence of Manufacturing and Alignment Error on the Maximum Tooth Fillet Stress of Involute Helical Gears

Abstract

For helical gears which have tooth form error and pitch error simultaneously, the calculating method of the maximum tooth fillet stress σ_max is shown, and the effect of tooth form on σ_max is discussed: The ratio between σ_max and the maximum tooth fillet stress of error free gears can be expressed as a function of two variables: one variable is the ratio between amplitude of tooth form error and tooth loading, and the other is the ratio between pitch-difference and tooth loading. Some charts and diagrams for the ratio concerning the maximum tooth fillet stress are shown. It is also theoretically shown, that the convex tooth form induces the least or almost least stress increase comparing with another tooth form, and for some gears convex tooth form prevents the stress increase due to pitch error, if its amplitude is properly chosen.