Macro geometry optimization of a helical gear pair for mass, efficiency, and transmission error. (February 2020) - Kim, Su-chul
Highlights: Macro geometry of a helical gear pair was optimized. The objective functions used were gear mass, efficiency, and transmission error. All three exhibited a trade-off relation in the optimal design space. Five combinations were set to compare the optimal solution performance according to the combinations of the objective functions. The optimization considering all three objectives showed better performance than the other combinations. Abstract: When designing helical gears, the goal is to optimize gear weight, efficiency, and noise while simultaneously achieving the required strength. In this study, the macro geometry of a helical gear pair was optimized for low weight, high efficiency, and low noise; further, trends of optimal solutions for five combinations of the three objectives were analyzed. The gear mass and efficiency were directly used as the design objectives. However, since the calculation of the gear noise is generally very complicated and time-consuming, the gear noise has not been directly used as the design objective, and the peak-to-peak static transmission error (PPSTE), which is the main source of the gear vibration, was selected as the design objective for the gear noise in the optimization. The objectives exhibited a trade-off relation between each other in the optimal space. If one of them was omitted, the objective considerably deteriorated. To analyze the results, the objectives were normalized and scored. As a result, most of the top ranks were from the optimal solutions considering the mass, efficiency, and PPSTE. Therefore, all three objectives should be considered in the gear optimization for low weight, high efficiency, and low noise.