输入转速不一致对机电短程截割传动耦合轮系动态特性的影响

Effect of inconsistent input speed on dynamics of torque coupled gear set in electromechanical short-range cutting transmission of shearer

为解决采煤机截割部摇臂箱体变形导致传动系统失效的问题,提出了由多台电动机、耦合轮系和行星轮系构成的机电短程截割传动系统。耦合轮系汇集多台电机的动力,其动态性能影响系统的承载能力和使用寿命。分析了引起耦合轮系输入转速波动且不一致的原因,在输入转速波动且相位差恒定的情况下,通过仿真研究了输入转速不一致对耦合轮系动态特性的影响规律。机电短程传动系统中的制造装配误差、多台电机转速响应的差异等因素可使耦合轮系输入转速波动且不一致。输入转速波动且不一致使耦合轮系的动态啮合力出现低频波动,且各个传动路线中的动态啮合力的相位不同;随输入转速不一致程度的增加,动态啮合力波动幅度增加。动态啮合力的低频波动使得作用在主动齿轮上的载荷出现低频波动,影响主动齿轮的切向和径向振动加速度;输入转速不一致程度由0增加至0. 005时,切向振动加速度增大11. 89 m/s^2,径向振动加速度增大7. 07 m/s^2,输入转速不一致对切向振动加速度的影响更大。进行了机电短程传动系统的动态特性实验,耦合轮系存在输入转速波动且不一致的现象,测得的耦合轮系输入轴振动加速度的时域特征与仿真结果的相近,振动加速度幅值谱的主要频率成分与仿真结果的相似,验证了仿真结果的合理性。

A compacted cutting powertrain consisting of multiple motors,a torque coupled gear train and a planetary gear train was proposed to avoid the influence of longwall shearers’ ranging arm deformation.Dynamic behavior of the torque coupled gear train affects the load carrying capacity and service life of the powertrain. Causes of inconsistent fluctuant input speeds in the torque coupled gear train were analyzed. Effects of the inconsistent input speeds on the dynamic behavior of the gear train were studied through simulating. Manufacturing and assembly errors in the powertrain and different responses from multiple motors can cause inconsistent fluctuant input speeds.Inconsistent fluctuant input speeds make the dynamic meshing forces in the torque coupled gear train to fluctuate.The phase of the dynamic meshing force of each transmission path is different from each other.The inconsistent input speeds also affect the pinion vibration acceleration in the torque coupled gear train.When the inconsistent degree of input speeds increases from 0 to0.005,the tangential and radial vibration accelerations increase by 11.89 and 7.07 m/s^2,respectively.The inconsistent input speeds have a greater impact on the tangential vibration acceleration.Some dynamic behaviors of the torque coupled gear train were verified by an experiment.There exist inconsistent fluctuant input speeds in the gear train.Features of the input shaft vibration acceleration acquired by the experiment are similar with those acquired by simulation in the time and frequency domains.