Reduction of planetary gear noise for the automatic transmission was investigated using dynamic stiffness strengthening of the transmission case and the mounting bracket. Dynamic stiffness of case was improved by the reinforcing rib and shape change, ...
Reduction of planetary gear noise for the automatic transmission was investigated using dynamic stiffness strengthening of the transmission case and the mounting bracket. Dynamic stiffness of case was improved by the reinforcing rib and shape change, through the FRF test, and 1’st mode frequency was also improved by the shape change of vehicle mounting bracket. After that, noise reduction was confirmed by the comparing before and after vibration and noise level of automatic transmission at the anechoic chamber and vehicle. Test results show that gear noise of transmission was improved 10dB at anechoic chamber and 8dB reduced in vehicle noise respectively.