Computer Simulation on the Heat Generation in Meshing of Plastic Spur Gears

In Case of Plastic Spur Gears Pair

Abstract

The application of injection molded plastic gears becomes widespread ; e.g., audio/video equipments, office equipments, and electronic equipments, because of their quietness. In addition, plastic gears are widely used even for power transmissions. When plastic gears are used for power transmissions, the strength evaluation of the gears is one of the most important issues. However, the allowable stress used for the strength calculations has been evaluated in consideration of only atmospheric temperature. Therefore, the strength calculations are not so reliable, because heat generation due to both friction between meshing tooth flanks and hysteresis of material were not considered. If the actual temperature of meshing teeth would be evaluated in consideration of the heat generation, more reliable allowable stress of the material could be obtained. The present paper describes three-dimensional analysis of heat generation and heat conduction of meshing plastic spur gears. As a result, the calculated increase in gear temperature coincided with measured one. Then, the allowable stress of material could be evaluated more accurately.