变速器齿轮敲击参数灵敏度分析

Sensitivity Analysis of Gear Rattle Parametric of Transmission

以某款手动变速器为研究对象,基于SIMdrive软件,搭建考虑输入轴转速波动、齿侧间隙、空套齿轮转动惯量及拖拽力矩等影响因素的变速器齿轮敲击仿真分析模型,计算各空套齿轮的角速度及各非承载齿轮对的啮合力。进行变速器齿轮敲击台架试验,测得空套齿轮转速信号,验证仿真分析模型的有效性。从冲击能量的角度出发,选取非承载齿轮对的啮合力对时间的导数为敲击评价指标(Jerk指标),并用向前差分法求解各个工况下的Jerk指标。分别对转速波动、齿侧间隙、空套齿轮转动惯量及拖拽力矩这4个参数求偏导,从而求得各参数对变速器齿轮敲击的灵敏度规律。发现转速波动对敲击的灵敏度始终为正,转速波动在40 r/min时,对敲击的影响开始陡增。齿侧间隙小于0.1 mm时,敲击灵敏度为正,大于0.1 mm时为负。空套齿轮转动惯量对敲击的灵敏度始终为负,在转动惯量大于0.000 6 kg·m^2时,敲击灵敏度值几乎不变,转动惯量的改变对敲击的影响并不明显。拖拽力矩小于0.6 N·m时,敲击灵敏度为负,大于0.6 N·m时为正,在0.2~0.3 N·m之间时,拖拽力矩对敲击的影响并不明显。

Taking a manual transmission as research object,a simulation analysis model of transmission gear rattle is conducted by using the SIMdrive software,this model considering the influencing factors such as input shaft speed fluctuation,clearance,inertia of loose gear and drag torque,and these influence factors are used to calculate the angular velocity of each loose gear and the engaging force of each idler gear pair. The transmission gear rattle is tested and the loose gear speed signals are measured to verify the effectiveness of the simulation analysis model. From the point of view of the impact energy,the derivative of the idler gear on the meshing force is taken as the rattle index( Jerk index),and using the forward difference method to solve the Jerk index under various conditions. The partial derivative of the four parameters of speed fluctuation,clearance,inertia of loose gear and drag torque are obtained respectively,and the sensitivity of each parameter to the transmission gear rattle is obtained. It is found that the sensitivity of the speed fluctuation to the rattle is always positive,and when the speed fluctuates at 40 r/min,the influence on the gear rattle starts to increase sharply.When the clearance is less than 0. 1 mm,the rattle sensitivity is positive,more than 0. 1 mm when the negative.The sensitivity of the inertia of loose gear is always negative,and when the inertia is more than 0. 000 6 kgm^2,the rattle sensitivity value is almost unchanged and the effect of the change in inertia on the gear rattle is not noticeable. When the drag torque is less than 0. 6 N·m,the rattle sensitivity is negative,more than 0. 6 N·m when the positive,and at 0. 2 N·m to 0. 3 N·m between the drag torque on the gear rattle is not noticeable.