控制油压对湿式多片离合器分离动态特性的影响

During the disengaging process of a wet-multi clutch, the disengaging time, the friction torque and the friction pair gaps have a dramatic influence on the shifting quality of the vehicle. Thus, a comprehensive dynamic model is proposed to investigate the clutch disengaging process, which includes hydrodynamic lubrication, elastic-plastic contact between asperities, spline friction, and impact between piston and clutch hub. The influence of control oil pressure and its decreasing rate on the disengaging performance of a six friction-pair wet clutch are studied, and the non-uniformity coefficient is employed to characterize the disengaging uniformity. The results show that the decline in the pressure's decreasing rate not only prolongs the disengaging time, but also deteriorates the disengaging uniformity dramatically. Moreover, the decline in contact torque is retarded and the viscous torque is increased. However, the initial value of control oil pressure has a slight influence on the disengaging time and uniformity. The rise in control oil pressure increases the initial contact torque and its decreasing rate, and also decreases the viscous torque.