The relation between heat generation and fatigue of plastic gears.

Abstract

Recently, the plastic gears are used for the dynamic gears. The fatigue of plastic gears is a problem which becomes progressively worse with use. When studying fatigue heat generated in plastic gears must be taken in consideration. There are two kind of heat that can be generated by the meshing of plastic gears. The first is frictional heat and the second is heat generation due to hysteresis. These heat generations give the local temperature rise in plastic gears. The elastic modulus and the coefficient of viscosity have an influence on the calculation of this heat. These two values are considered to change by fatigue of plastic materials. This paper describes the relation between the elastic modulus and the coefficient of viscosity have an influence on the calculation of this heat. These two values are considered to change by fatigue of plastic materials. This paper describes the relation between the elastic modulus and the coefficient of viscosity, giving more clarification to the fatigue phenomenon. The calculated values of equilibrium temperature and local temperature were compared with the measured values, and the two values were found to agree with each other. Calculated values of the temperature rise of plastic gear could be obtained with better accuracy. The results provided data for the design and use of new and better plastic gears.