考虑行走弹性影响下的车辆换挡过程分析

为研究行走弹性对工程车辆行走换挡过程的影响，建立了考虑驱动轮轮胎变形引起的车辆行走弹性影响的整车行走动力学模型，该模型适用于换挡过程分析。计算与分析了典型装载机动力换挡过程，将考虑或不考虑行走弹性时计算得到的整车加速度和瞬时冲击度的变化过程分别进行了对比，利用实车试验对单一换挡过程进行了验证；并将考虑行走弹性时升挡过程中变速箱输入输出转速变化过程、离合器滑摩功率特性的计算结果与不考虑行走弹性时换挡过程的计算结果进行了对比。研究结果表明：与不考虑行走弹性的情况相比，行走弹性变形使得换挡过程中整车加速度的变化更加平缓；换入挡离合器有两次滑摩过程，冲击度更小，换挡时间更长；离合器接合时的冲击度与其接入时间有关；滑摩功更小。

Vehicle Shifting Process Analyses in Consideration of Walking Elasticity

In order to study the influences of walking elasticity on the shifting processes of construction vehicles, a vehicle walking dynamics model was established considering the influences of driving wheel tire deformations on vehicle walking elasticity, which was suitable for shifting process analyses. The dynamic shifting processes of typical loaders were calculated and analyzed, and the calculated change processes of acceleration and instantaneous impacts of the vehicle with and without considering the walking elasticity were compared respectively. The results of gearbox input and output speed variations and clutch sliding friction power characteristics in the processes of gear shifting with the consideration of walking elasticity were compared with those of gear shifting processes without the consideration of walking elasticity. The results show that compared with the situations without considering of walking elasticity, the changes of vehicle acceleration during gear shifting processes are more gentle. The shift into the clutch has two sliding processes, less impact, longer shift time. The impact of clutch engagement is related to the connection time. The sliding friction work is smaller.