A Parametric Study to Investigate the Dynamic Behavior of Worm Gear with Plastic Wheel

Plastic gears use is in an increasing growth. Plastic material has many interesting characteristics that cannot be found in metallic ones. Searching for more efficiency, combining advantages of metallic and plastic components of worm gears sets is thus employed. Most of the researches done for years had focused on the phenomena that occur in the contact area between the worm and the wheel. In this paper, a parametric approach is presented to, quickly and efficiently, investigate the vibration levels of worm gears including plastic wheel and metallic worm. A dynamic model is first described to establish equations of motion. The viscoelasticity of the worm gear’s material is then taken into consideration. It is described by two parameters: The storage modulus describing the elastic behavior; and the loss factor describing the viscous one. The dependency of viscoelastic materials on frequency and temperature is considered. A parametrized linear viscoelastic problem is thus investigated here. Finally, numerical simulation based on modal analysis is established. The result is an estimation of the evolution of natural frequencies regarding the variation of the viscoelastic material’s parameters. Consequently, it can give the range of frequencies that can reach a worm gear model including a specific plastic material.