基于台架NVH试验环境的制动器虚拟样机分析

Virtual Prototype Analysis of Brakes Based onNVH Test Environment

针对NVH台架试验时某汽车鼓式制动器产生的制动抖动现象,在ADAMS软件中建立该鼓式制动器各部件模型、边界和载荷条件,以及NVH实验台相关模型,得到包含试验环境的虚拟样机模型。仿真分析拖滞制动工况时低频振动的激励源和传递特性。结果表明:制动抖动现象是因为摩擦衬片各部位和制动鼓接触不同步所致的低频振动,与制动压力和转速等因素有关;悬架的螺旋弹簧下端振动最大,减振器和衬套都起到了对振动衰减的作用。

To study the braking judder phenomenon of an automobile drum brake during NVH bench test,the model of the drum brake as well as the related model of NVH test bench were established in ADAMS.The virtual prototype model including test environment was obtained.The excitation source and transmission characteristics of low frequency vibration in drag braking status were simulated and analyzed.The results show that the braking judder is due to the low frequency vibration caused by the out-of-synchronous contact of the friction lining,which is related to the braking pressure and rotation speed.The vibration at the bottom end of the suspension coil spring is the largest,shock absorber and bushing play an important role in vibration attenuation.