钢板弹簧的扭转特性分析及其对制动性能的影响研究

Study on torsional characteristics of leaf spring and its influence on braking performance

为了研究钢板弹簧在制动过程中扭转特性及其对汽车制动抖动和制动使用性能的影响,首先针对某型商用车在紧急制动中后桥的抖动现象进行了分析和实验研究,并通过测试数据分析了制动抖动的特征以及对汽车使用性能的影响,然后根据后桥在制动中的受力模型阐述了钢板弹簧在制动中的抖动机理,进而利用仿真平台Adams软件在Chassis模块中建立等刚度钢板弹簧模型,并结合View中建立的商用车整车模型模拟整车紧急制动的工况,研究了钢板弹簧在制动过程中的扭转特性,分析了前后轮的制动时间差对后桥抖动的影响,并提出了增大钢板弹簧纵向角刚度的改进措施。仿真结果表明,采用改进措施后的后桥质心制动时的最大摆动角减小17.8%,第二峰值摆动增量由6.99°降为2.1°,后轮胎跳离地面次数由4次减少为2次。研究结果从钢板弹簧扭转特性的角度为后续的设计及匹配提供了参考。

In order to determine the torsion characteristic of leaf springs during braking and its influence of vehicle braking jitter and braking performance, the rear axle＇s torsion of a designated commercial vehicle during emergency braking was analyzed and experimentally studied. The characteristic of brake jitter and its influence on vehicle performance was analyzed according to experimental data. Afterward, the torsional mechanism of the leaf spring in braking was expounded according to the force analysis of the rear axle model. Furthermore, the equal stiffness leaf spring model was established by using the Chassis module of the simulation platform Adams software, and the emergency braking condition of the whole vehicle was simulated by the commercial vehicle model which was built in View module. The torsional characteristic of leaf spring during braking was determined, and the influence of the braking time difference between front and rear wheels on the torsion of the rear axle was analyzed. Finally, the improvement measure to increase the longitudinal angular stiffness of leaf spring was proposed. The simulation results show that the maximum swing angle of the rear axle eentroid of the improved model decreased by 17.8% during emergency braking , the second peak swing decreased from 6.99 degrees to 2. 1 degrees, and the times of rear tires jumping off the floor were reduced from 4 to 2 by comparing with original model. The results can provide reference for designing suspension and matching the angle of torsion of leaf spring.