行星齿轮传动系统碰撞振动特性研究

Vibro-Impact Characteristics of Planetary Gear Transmission

针对行星齿轮传动系统轻载高速下存在碰撞振动的问题进行了研究,为此提出了研究方法和分析模型,即在大载荷下采用线性弹簧来模拟轮齿啮合弹性,在轻载下采用Hertz接触理论来计算齿轮副碰撞力,最终采用集中质量方法建立了行星齿轮传动系统碰撞振动分析模型。研究分析发现:在大载荷、连续增速下,行星齿轮传动系统在太阳轮与行星架扭转振动模式以及内齿圈横向振动模式所对应的固有频率位置出现了共振,并引起了较大的啮合力波动;在轻载下,齿轮副啮合状态发生了变化,出现了碰撞振动,随着负载的增加,接触力的变化呈现出强非线性特征,齿轮副脱啮时间逐渐缩短;当负载达到门槛值时,齿轮副不再脱啮;随着转速的提高,脱啮时间逐渐缩短,碰撞力波动幅值呈线性增大的趋势。该结果可为行星齿轮传动系统减振、降噪研究提供理论依据。

In order to study the dynamic vibro-impact characteristics of planetary gear transmission system under the operating conditions of high speed and light load, a new planetary gear transmission modeling method is presented. In the modeling process, linear springs were used to simulate gear mesh elasticity under heavy load cases, and the Hertz contact theory was used to calculate the contact force under light load cases. In addition, the vibro-impact model of a planetary gear transmission was established by using lumped mass method. The effects of the operating conditions on the system vibro-impact characteristics are analyzed. As results show that, with the growing of the input speed, the mesh force exhibits obvious fluctuations due to the resonance of the sun gear and carrier appears torsion vibration, ring gear＇s transverse vibration under the heavy load. Under the light load condition, the vibro-impact occurs in the gear pair, the changing trend of the contact force shows strongly nonlinear characteristics. The time of contact loss in gear pair decreases gradually as the load is increased, until it is reach vibro-impact threshold value, then no contact loss happens. With increasing of the input speed, the time of mesh-apart is decreased gradually, and the fluctuation amplitude of contact force shows a linearly increasing trend. The study provides useful theoretical guideline to the low-noise design of planetary gear transmission.