Study on power split characteristics of planetary multistage face gear transmission device and its effect to drive efficiency under variable speed working condition

摘要

The planetary gear system consists of several concentric single stage face gears symmetrically meshing with multiple cylindrical gears that as the core component of planetary multistage face gears transmission device (PMFGTD), which is the key to realizing shifting and principle innovation that able to flexibly extend the speed ratio region of single stage face gear. The speed ratio distribution mechanism is directly related to the feasibility of the design scheme. The stability, reliability and loading capacity of each power split branch affect the performance of the whole system directly. For the requirements of maximizing drive efficiency and optimizing drive performance under different conditions, this study analyzes the gear matching relationship and driving characteristics by using numerical calculation method basing on the PMFGTD structural characteristics, and calculates the corresponding transmission ratio value. According to the torque equilibrium equation, the torque relation and power ratio relation of each component are established, and then the power distribution relation between system components is calculated. The flow characteristics of system input power and each branch output power under the condition with or without meshing power loss are analyzed. The influence relationship model of power split coefficient on drive efficiency is established to calculate the corresponding rules, thus the dynamic characteristics of PMFGTD on power split under various working conditions are proved by experiments. The result provides reference for the transmission ratio distribution and structure design of planetary multistage face gears transmission.