The final work deals with thermomechanical heating of a polymer gear tooth due to cyclic loading. The first part of the work focuses on the theoretical basis and current research on heating and loading of polymer gears. We considered a gear tooth whose width is twice it’s length, whereby shear stresses are no longer negligible. We focused on the influence of shear stresses on heating, so we used Timoshenko’s theory of beams for the mechanical equations. The model includes the influence of stress, deformation, friction, inhomogeneity of the cross-section due to the involute shape and the movement of force along the length of the gear tooth. Heating and cooling were calculated analytically using the thermal equation. The results were compared with the Euler-Bernoulli theory. They showed that, during cyclic loading, shear has no significant effect on heating. However, it has a great influence on stresses and deformations in the problem under consideration. We then showed how heat is generated in a gear tooth due to frequency, force and friction.
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