In order to study the influence of tooth surface friction on the non-linear bifurcation characteristics of multi-clearance gear drive system, a 6 degree-of-freedom bending torsional coupled vibration model was established. The time-varying mesh stiffness, backlash, support clearance and damping were considered comprehensively in this non-linear vibration model. Loaded tooth contact analysis was used to calculate the time-varying mesh stiffness. Based on the elasto-hydrodynamic lubrication, the time-varying friction coefficient was calculated. Runge–Kutta numerical method was used to solve the dimensionless dynamic differential equation. Using phase diagram, Poincaré diagram, time history diagram, and spectrum diagram, the influence of tooth surface friction on bifurcation characteristics was studied. The results show that the system undergoes a change from 1-periodic motion, multi-periodic motion, to chaotic motion through bifurcation and catastrophe when the speed changes independently. When the friction coefficient of tooth surface changes from 0, 0.05 to 0.09, the chaotic motion of the system is suppressed. Similarly, with the increase in tooth friction, the chaotic motion characteristics are suppressed. Tooth surface friction is the main factor affecting chaotic motion. With the increase in friction coefficient of tooth surface, the chaos characteristic does not change obviously and the vibration amplitude decreases slightly.

为了研究齿面摩擦对多间隙齿轮传动系统非线性分叉特性的影响，建立了六自由度弯曲扭转耦合振动模型。在该非线性振动模型中，时变网格刚度，齿隙，支撑间隙和阻尼被综合考虑。加载的齿接触分析用于计算随时间变化的网格刚度。基于弹性流体动力润滑，计算了随时间变化的摩擦系数。Runge-Kutta数值方法用于求解无量纲的动态微分方程。利用相图，庞加莱图，时间历程图和频谱图，研究了齿面摩擦力对分叉特性的影响。结果表明，当速度独立变化时，该系统经历了从1周期运动，多周期运动到分叉和突变的混沌运动。当齿面的摩擦系数从0、0.05变为0.09时，系统的混沌运动得到抑制。类似地，随着牙齿摩擦的增加，混沌运动特性被抑制。牙齿表面摩擦力是影响混沌运动的主要因素。随着齿面摩擦系数的增加，混沌特性没有明显改变，振动幅度略有减小。09，系统的混沌运动被抑制。类似地，随着牙齿摩擦的增加，混沌运动特性被抑制。牙齿表面摩擦力是影响混沌运动的主要因素。随着齿面摩擦系数的增加，混沌特性没有明显改变，振动幅度略有减小。09，系统的混沌运动被抑制。类似地，随着牙齿摩擦的增加，混沌运动特性被抑制。牙齿表面摩擦是影响混沌运动的主要因素。随着齿面摩擦系数的增加，混沌特性没有明显改变，振动幅度略有减小。