Abstract：The interior sound quality of automobiles is greatly affected by gear rattle noise. To investigate the neutral gear rattle problem of automotive transmission, a lumped parameter model with four degrees of freedom was established with two nonlinear factors of the clutch torsional stiffness and the elastic compression force between conjugate gear pair. Based on the model of gear rattle problem, the dynamic equations were established to determine the rattle criterion. The influences of clutch parameters and nonclutch parameters were analyzed in detail through simulation. The clutch parameters include stiffness, hysteresis, viscous damping coefficient and stiffness transition, while the nonclutch parameters include damping coefficient and inertia of input gear and output gear, engine speed and amplitude of excitation torque. The results show that for the clutch parameters, low stiffness and hysteresis of first stage are required to obtain low rattle level.Because the rattle level reduces firstly and then increases with the increase of viscous damping coefficient, there is an optimal value of viscous damping coefficient to realize low rattle level. For the nonclutch parameters, the decreased damping coefficient of input gear and inertia of output gear, the increased damping coefficient of output gear and inertia of input gear, the enhanced engine speed and the low amplitude of excitation torque are preferable to reduce the gear rattle.
2013, Vol. 34 
