考虑正负转速差的湿式离合器带排扭矩损失研究

Research on the Drag Torque Losses of Wet Clutch Considering Positive and Negative Rotational Speed Difference

基于某湿式多片式离合器的实际结构与带排扭矩损失的产生机制,分析在正负转速差下油液对摩擦片油槽作用的不同以及对带排扭矩损失的影响,并通过仿真与试验获得正负转速差下带排扭矩损失的变化规律。仿真与试验结果表明:在负转速差下,由于摩擦片的转速较大,其油槽侧面产生的动压力也较大,带排扭矩损失也相比正转速差时要大。对离合器带排扭矩损失在正负转速差下对自动变速箱换挡过程换挡力的影响进行分析,发现负转速差下需要的换挡力比正转速差下的换挡力大,因此负转速差下有换挡困难的风险。

Based on the actual structure of a wet multi-plate clutch and the mechanism of generating drag torque loss,the different effects of oil on the friction plate oil groove and the influence on the drag torque loss under the difference of positive and negative rotational speed were analyzed,and the variation rule of drag torque loss under the difference of positive and negative rotational speed was obtained through simulation and experiment.Simulation and test results show that under the negative speed difference,due to the larger speed of the friction plate,the dynamic pressure generated on the side of the oil groove is also larger,and the drag torque loss is also larger than that with the positive speed difference.The influence of the clutch drag torque loss on the transmission shift process was analyzed.It is found the shift force required under negative speed difference is larger than that under positive speed difference.Therefore,there is a risk of difficult shifting under negative speed difference.