A METHOD FOR THERMAL-ANALYSIS OF SPIRAL BEVEL GEARS

A modelling method for analyzing the three-dimensional thermal behavio r of spiral bevel gears has been developed. The model surfaces are gen erated through application of differential geometry to the manufacturi ng process for face-milled spiral bevel gears. Contact on the gear sur face is found by combining tooth contact analysis with three-dimension al Hertzian theory. The tooth contact analysis provides the principle curvatures and orientations of the two surfaces. This information is t hen used directly in the Hertzian analysis to find the contact size an d maximum pressure. Heat generation during meshing is determined as a function of the applied load, sliding velocity, and coefficient of fri ction. Each of these factors change as the point of contact changes du ring meshing. A nonlinear finite element program was used to conduct t he heat transfer analysis. This program permitted the time- and positi on-varying boundary conditions, found in operation, to be applied to a one-tooth model. An example model and analytical results are presente d.