Abnormal Noise Source Identification and Control for Automobile Transmission in the Neutral Idle Condition

Aiming at the abnormal noise of a domestically-made automobile transmission in the neutral idle condition, seriously affecting the vehicle market competitiveness and the riding comfort ability for customers, the objective of this study to reduce the noise and vibration of the automobile transmission by accurately identifying the noise source of the transmission in the neutral idle condition. For this purpose, based on the working characteristics of the transmission, modal analysis of automobile transmission housing is formulated using 3D graphics software Pro/E together with Finite Element Method. In addition, the calculation of meshing frequency of gear pair is conducted also. Finally, through comparing model analysis results to the calculation results, it is indicated that the gear meshing impact noise of the third gear pair was identified as the noise resource of the automobile transmission in neutral idle condition, which will provide the theoretic basis to analyze its dynamic characteristics of the transmission as well as its improvement to reduce vibration and noise.