为了改善汽车驱动桥动态性能，提出基于 Ease-off 修形准双曲面齿轮齿面减振优化设计方法。该方法通过预置传动误差参数及抛物线修形参数设计小轮法向 Ease-off 曲面，小轮修形齿面表示为与大轮共轭的小轮齿面叠加 Ease-off 曲面。结合齿面接触分析 (TCA)、齿面承载接触分析 (LTCA) 方法获得齿轮啮合刚度。以啮合位置受力分析为基础，应用集中质量法建立准双曲面齿轮弯－扭－轴耦合动力学模型，采用数值方法求解运动微分方程得到系统的振动响应。以法向振动加速度均方根最小为优化目标获得最佳修形齿面，并分析修形导致的刚度波形及幅值变化对系统动态性能的影响。算例表明: 当修形量过大时导致刚度下降较多，引起法向振动增加; 修形齿面的平均啮合刚度相差不大情况下，刚度曲线的形状较幅值对振动的影响更为敏感; 最优 Ease-off 修形后系统振动明显降低，齿轮副的平均啮合刚度下降较少且刚度曲线中主要为啮合频率，基本无倍频成分; 修形齿面承载传动误差幅值 (ALTE) 降低且曲线中的高频成分增加时，未必能减小振动; 多载荷 ALTE 曲线基本可以反映振动随载荷的变化趋势。

An optimization design method of vibration reduction for ease-off modification based hypoid gears was proposed to improve dynamic performances of automobile drive pinion axle． The modified pinion were represented by a sum of two vector functions determining the tooth of conjugate and the pinion normal ease-off deviations ，which were expressed by both predesigned transmission error function and tooth profile modification curves． Mes-hing stiffness was obtained with tooth contact analysis (TCA) and loaded tooth contact analysis (LTCA)． Based on force analysis of the meshing position，the bending-torsional-axial coupling dynamic lumped mass model for hy-poid gears was established，and the vibration response of the system was obtained by solving the differential equa-tion of motion with numerical method． The best ease-off deviations were determined by a optimizing minimal mean square value of normal vibration． Besides，influences of stiffness curve shape and amplitude caused by modifica-tion on the dynamic performance of the system were explored． A numerical example shows that excessive modifica-tion leads to decrease of meshing stiffness，which are responsible for the increase of normal vibration． In case of a little differences in value of average meshing stiffness for the modified tooth surfaces，the shape is more sensitive to vibration than the amplitude for stiffness curve． After the optimal ease-off modification，the vibration of system is obviously reduced． Besides，the average meshing stiffness decreases a little and main frequency in the stiffness curve is meshing frequency，and there is no frequency doubling component． When the amplitude of load transmis-sion error (ALTE) decreases and the high frequency component in the curve increases，the vibration may not be reduced，and ALTE can basically reflect the variation tendency of vibration with loads．