In the final thesis, we analyzed the deformation state of a polymer gear tooth, which is a result of the forces in contact with the driving and driven gear. The gear tooth
is treated as a cantilever beam with variable geometry along its length. The contact force, which moves along the tooth flank with time, is simplified as a vertical force
acting at the end of the beam. The deformation was calculated according to two deformation theories (Euler-Bernoulli and Timoshenko beam theory), which were compared.
The equations that describe the change in position of the neutral axis are first derived assuming an elastic beam with constant mechanical properties. With the help of
defining the temperature field of the gear tooth and certain assumptions, we included an essential property of polymer materials in the mathematical model - dependence of
mechanical properties on elevated temperature, which is a consequence of losses due to viscoelasticity of the material. We evaluated the amount of heat generated in the
tooth and compared the deflection of the beam with temperature-dependent mechanical properties to the deflection of the beam with constant mechanical properties. The aim was to demonstrate the suitability of both deformation theories under different circumstances and emphasize the importance of considering the influence of temperature when ensuring the reliability of polymer gears.
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