Tooth Fillet Stresses of Gear with Thin Rim : 3rd report, Examination of Approximation Formulae for Gear Tooth Fillet Stresses

To confirm the reliability of the approximation formulae for tooth fillet stresses of thin-rimmed gears (5) and to reveal the influences of many factors on the stress value, the tooth fillet and root stresses of a thin-rimmed gear calculated by the approximation formulae have been compared with the FEM calculated values : The influences of the radius of curvature of tooth fillet, of the width of the bottom of tooth space, of the pressure angle and of the loading position on tooth flank on the tooth fillet and root stress distribution for the case of a rack have been investigated and the scope of validity for the approximation formulae has been indicated. The calculation of the fillet and rootstresses for the loaded and unloaded teeth under a single and double tooth pair meshing was worked out by use of the approximation formulae, and the accuracy of calculation has been confirmed to be as good as that of FEM.