摘 要：对一款轿车变速器存在的噪声问题进行研究。分析变速器噪声的组成部分。对该变速器进行半消声室台架实验，通过频谱分析、贡献量分析等方法找到特征频率。计算发现该问题较为特殊，针对因设计不当出现不同传动部件特征频率一致的情况，利用声学照相机技术基本确定辐射声源位置。考虑噪声特征频率范围与箱体的模态频率范围较为接近，通过有限元法计算箱体的模态频率，发现箱体出现共振。研究为修改传动部件参数、变速器箱体结构提供参考依据。

Abstract: The source of gear whine in automotive transmission is identified. Firstly, the whine noise is tested in the Hemi-anechoicroom.Through frequency spectrum analysis and noise contribution analysis ,the whine spectrum is found. The problem is special that different gears have the same mesh frequency. Aim at this special problem, the acoustic camera is used and the source of the gear whine is found.Finally,through FEM the nature frequency of the transmission house is caculated.The transmission house is resonated in some frequency.The research provides experiment basis for modification of the gear design parameter and the structure of the transmission house to achive low noise transmission.