动力总成异常振动的研究

针对某SUV车动力总成产生的异常振动,运用自主开发的模态分析系统,通过动力总成单独的模态试验及整车的道路试验和转鼓试验,连续测量换挡杆的振动信号并进行分析处理。结果表明,换挡杆异常振动的根本原因是飞轮壳和离合器壳刚度相对较低,以致动力总成固有频率偏低,落在发动机工作转速对应的2阶激振频率区间而引起共振。通过对飞轮壳的结构进行改进,消除了换挡杆的异常振动。

Research of Abnormal Vibration for Power Assembly

In view of the abnormal vibration of the powertrain of a sport utility vehicle, by utilizing the self-developed modal analysis system and conducting the separate modal test of powertrain and the complete vehicle tests on road and chassis dynamometer, the vibration signals of shift level are continuously measured, analyzed and processed. The results show that the radical cause of the abnormal vibration of shift level is the relatively low stiffness of flywheel housing and clutch housing, leading to low natural frequency of powertrain, which falls into the range of 2nd-order excitation frequency corresponding to the working rotation speed of engine, resulting in resonance. The modifications of the structure of flywheel housing eliminate the abnormal vibration of shift level.