弹性模量-温度效应对POM齿轮副啮合刚度的影响OA

With the emergence of high-strength engineering plastics,plastic gears have begun to be widely adopted in power transmission.However,their mechanical properties exhibit significant temperature sensitivity.To accurately evaluate the meshing stiffness of polyoxymethylene(POM)gear pairs under varying temperatures,this paper proposes a calculation method for the time-varying meshing stiffness of plastic gear pairs that incorporates the Young's modulus-temperature effect.Firstly,combined with the theories of gear grease lubrication and convective heat transfer,the frictional heat flux density and convective heat transfer coefficient of the gears were calculated,and the Young's modulus-temperature curve of the POM material was obtained through a temperature-controlled tensile test.Subsequently,a thermoelastic contact model of the gear considering the Young's modulus-temperature effect was constructed based on the finite element,and then verified by the Blok flash temperature theory.Finally,based on this model,the temperature field and stress field during the meshing process of the POM spur gear pair,as well as the influences of ambient temperature,torque,and rotational speed on the meshing stiffness,were studied.The research results show that the Young's modulus-temperature effect has a negligible impact on the steady-state temperature field of plastic gear pairs.However,it can enhance the meshing stiffness of plastic gears at low temperatures,while it will also significantly weaken the meshing stiffness above room temperature.Therefore,when evaluating the meshing stiffness of plastic gears,the influences of temperature rise and modulus-temperature effect should be taken into account to avoid the design risks caused by overestimating the gear meshing stiffness.