中文摘要：

一对齿轮的正确啮合条件是它们的法节相等，由此给出了非等模数非等压力角齿轮副的无侧隙啮合方程式、齿轮副基本参数和接触应力计算式等；综合考虑轮系的承载能力、结构紧凑、重量轻等，以轮系的体积最小和行星轮个数最优为目标函数，以齿轮的接触强度、弯曲强度和胶合强度，重合度和结构条件为约束条件，建立优化设计数学模型；应用Matlab优化工具箱中的Fmincon进行三次分步优化求解，将新设计方案与原设计方案和等模数等压力角方案相比，体积分别减小20．2％和17．2％。

英文摘要：

For a pair of gears, the correct action condition is that their normal pitches are equivalent. Under this correct action condition, non-backlash action equation, essential parameters and contact stress computing formula were given for gears with non-equivalent modulus and pressure angle. Comprehensive consideration of loading ca- pacity, compact structure and light-weight of this NGW planetary gear transmission, was applied to building the op- timization design model unlike the existing model. In the model, the mechanism＇s smallest volume and the number of planetary were taken as the objective functions, while the contact intension, bend intension and scoring inten- sion, the contact ratio, and structural conditions were taken as the constraints. Then the function Fmincon in the optimization Toolbox of Matlab was used to solve the model by three steps. Compared with the original scheme and the common optimization design scheme with equivalent modulus and pressure angle, the transmission volume is reduced by 20. 2% and 17.2% respectively.