大功率拖拉机悬浮前桥设计、调试与试验

Design,commissioning and test of suspension front axle of high‑power tractor

针对现国产大功率拖拉机驾驶舒适性差、易驾驶疲劳、作业效率低等问题,设计一种非独立悬浮前桥,运用仿真分析、边界试验、响应试验、隔振质量试验等对其结构参数进行优化确定。按照悬浮前桥寿命15000 h,拖拉机最高时速40 km/h,最大制动减速度5 m/s^(2),悬浮量±65 mm的边界,结合理论分析与经验设计,初步确定悬浮前桥刚度值310~980 N/mm,对应的无阻尼固有频率范围小于2.0 Hz;阻尼系数范围0.2~0.7 s^(-1);模式切换时,位置调整时间6~30 s,泄压时间小于30 s。仿真分析与边界试验的结果表明:悬浮前桥满足15000 h寿命要求,满足40 km/h最高时速,最大制动减速度5 m/s^(2)的使用需求。经响应试验验证及优化,模式切换时,位置调整时间为3.57~14.71 s,泄压时间小于16.69 s。隔振质量试验表明,无阻尼固有频率小于1.8 Hz,阻尼系数0.45~0.56 s^(-1)。

In view of the problems of poor driving comfort,easy driving fatigue and low working efficiency of the domestic high‑horsepower tractor,a non‑independent suspension front axle is designed,the structural parameters are optimized and determined by simulation analysis,boundary test,response test and vibration isolation quality test.According to the boundary of suspension front axle life of 15000 hours,tractor maximum speed of 40 km/h,maximum braking deceleration of 5 m/s^(2),suspension capacity of±65 mm,combined with theoretical analysis and empirical design,the stiffness value of the suspension front axle is initially determined to be 310-980 N/mm,and the corresponding undamped natural frequency range is less than 2.0 Hz.The damping coefficient range is 0.2-0.7 s-1.When the mode is switched,the position adjustment time is 6-30 s,and the pressure relief time is less than 30 s.The results of simulation analysis and boundary test show that the suspension front axle meets the life requirement of 15000 hours,the maximum speed of 40 km/h and the maximum braking deceleration of 5 m/s^(2).After the response test and optimization,the position adjustment time is 3.57-14.71 s and the pressure relief time is less than 16.69 s when the mode is switched.The vibration isolation quality test shows that the undamped natural frequency is less than1.8 Hz,and the damping coefficient is 0.45-0.56 s-1.