Design of helical gear transmission systems with high power density

High power density has become an important development direction of gear transmission system. The current research is solely focused on the volume or the efficiency, but the combination of the two is extremely lacking. In the paper, the design method of helical gear transmission system with high power density is put forward. Firstly, the transmission efficiency model of helical gear is proposed by the calculation of sliding friction power losses of meshing point and the further integral along the meshing line. Secondly, volume formulas of different structure of helical gears arc derived, and the volume model of helical gear transmission system is proposed. Finally, the optimization to minimize the volume and power loss (i.e., the highest transmission efficiency) of helical gear transmission system is set as the target. The linear weighted combination method is used to construct the target function; the design parameters of helical gear are set as the optimization variables. To meet the helical gear design and requirements of transmission are set as the constraint conditions; the design method of high power density of helical gears transmission system is proposed. A single stage helical gears transmission system is used to demonstrate the proposed method; the optimal design is completed. It can be found that the power loss of the optimized gear system is reduced by 18.07%, and the volume is reduced by 11.39%.