湿式多片离合器摩擦转矩衰减特性分析

Experimental study on attenuation characteristics of friction torque transferred by the wet multi-disc clutch

摘要:

为研究湿式多片离合器滑摩过程中摩擦转矩衰减现象，在SAE#2试验台制动工况下进行了不同摩擦副数离合器的摩擦转矩试验.针对于湿式多片离合器的摩擦转矩衰减现象，提出湿式多片离合器摩擦转矩衰减系数，以表征多摩擦副离合器实测摩擦转矩相对于计算摩擦转矩的减小程度.根据两副和六副摩擦转矩试验拟合得到受相对转速和平均面压影响的两副－六副摩擦转矩衰减系数，并分析相对转速和平均面压对摩擦转矩衰减值和摩擦转矩衰减系数的影响.研究表明：摩擦转矩衰减系数受摩擦转矩衰减值和计算摩擦转矩的共同影响，在润滑流量充足的条件下，摩擦转矩衰减值随着相对转速的增大逐渐减小，随着平均面压的增大而增大；而摩擦因数随相对转速和平均面压的变化规律较为复杂, 但总体上湿式多片离合器摩擦转矩衰减系数呈现随相对转速的增大逐渐减小，随平均面压的增大先增大后减小的趋势.

Abstract:

Sliding friction experiments of wet multi-disc clutch with different frictional pairs under braking condition in the SAE#2 test bench are designed to investigate the friction torque attenuation phenomenon. The attenuation coefficient of friction torque of wet multi-disc clutch is proposed to describe the decrease degree of the tested friction torque. According to the test data of friction torque transferred by two and six frictional pairs respectively, the calculation formula of attenuation coefficient for two-six frictional pairs is fitted and the influences of relative rotational speed and average pressure on attenuation coefficient are analyzed. The results show that the attenuation coefficient is influenced by attenuation value of friction torque and calculated friction torque. Under the full oil film condition, the attenuation value of friction torque decreases with the rise of the relative rotational speed and increases while the average surface pressure increases. In general, the attenuation coefficient declines with the rise of the relative rotational speed, and when the average surface pressure increases, the coefficient increases first and then decreases.