The design of low-noise gear transmissions and their guaranty in practice

During the last years the legislator pushed the reduction of traffic noise caused by automobiles. That is why up to now subordinate sources of noise, for example the manual transmission, become the focus of attention. First of all, the noise excitation in manual transmissions is determined by the contact conditions in gear meshing. Therefore it is of major importance to develop and to calculate strength- and noise-optimized contact geometries already during gear configuration. The tool introduced in this publication is used to iteratively calculate the best possible gear configuration considering the particular boundary conditions. A further option is to represent the influences of precision tuning of gearing on the acoustic performance. Only by firm examination of the concrete vehicle's components and correlation with the results of the transmission end-of-line test bench a high acoustic quality can be ensured. If the acoustic performance of the transmission components is analyzed early with manufacturing conditions (tolerance examinations) in mind, a sufficient precise balancing between subjective assessment by the customer and objective measurement on a test bench can be achieved.