Only on the basis of understanding and mastering the mechanism of transmission noise of electric vehicle reduction gearbox and helical gear pair, can we suit the remedy to the case, so as to improve the characteristics of gear vibration and noise by rational use of gear modification technology. Therefore, the mechanism of vibration and noise of electric vehicle reduction gearbox and helical gear pair is deeply analyzed.
The formation mechanism of reduction gearbox noise and gear vibration noise of electric vehicle is deeply studied, the nonlinear vibration mathematical model of the first level helical gear pair is established, and the vibration excitation of the helical gear pair, especially the internal dynamic excitation, is deeply analyzed. The main conclusions are as follows:
(1) The gearbox noise is the most serious in the whole vehicle noise of electric vehicles, and the gear whine and gear rattle are the main sources of gearbox noise.
(2) The internal dynamic excitation and tooth shape of helical gears are the main factors affecting the vibration noise of helical gears, especially the howling noise.
(3) The meshing impact excitation is mainly caused by the joint action of stiffness excitation and error excitation, and belongs to force excitation. Therefore, the meshing impact excitation can be suppressed by simultaneously reducing the transmission error, time-varying meshing stiffness and time-varying meshing force.