【作者】 裴中涛；

【导师】 李剑敏；

【作者基本信息】 浙江理工大学 ， 机械设计及理论， 2012， 硕士

【摘要】 装载机属于铲土运输类工程机械，具有作业速度快、效率高、机动性好等优点，因而成为工程现场施工的主要机种之一。驱动桥作为装载机传动系统的关键结构部件，准确的激励载荷分析和动力学响应分析是进行驱动桥动态特性分析的基础，利用虚拟样机技术来分析预测驱动桥传动部件的动力学响应可以提高其传动性能、缩短研发周期等；驱动桥桥壳支撑着装载机的荷重，并将载荷传给车轮，并且承受来自路面和装载机本身的各种冲击和作用，根据实践总结，引起桥壳破坏的主要形式是交变载荷作用下损伤长期积累而导致的疲劳失效。本文以装载机驱动桥为研究对象，结合浙江省科技厅重大科技专项项目（2009C11111）“轮式装载机驱动桥关键技术研究与产业化”，对ZL50型驱动桥进行了动力学特性分析及桥壳疲劳寿命预测的研究。首先利用UG建立了驱动桥各零部件的三维实体模型并进行装配，进行了其运动学和动力学理论分析。考虑了桥壳和半轴的柔性效应，通过建立桥壳和半轴的模态中性文件将其作为柔性体，并根据装载机某种实际行驶工况，建立轮胎和路面谱，在Adams中得到驱动桥刚柔耦合多体动力学仿真模型，并进行了运动学和动力学仿真分析，得到了驱动桥传动系的一些动态特性，仿真结果与理论吻合。由于装载机行驶工况比较复杂，本文针对驱动桥通过某种仿真路面的动力学分析对主要承载部件驱动桥壳进行了动态安全性分析，得到其动载荷文件，结合Ansys对桥壳进行了有限元静力学分析，利用分析结果得到的桥壳的应力谱，在nSoft的疲劳分析模块中，对桥壳进行了基于有限元模型的疲劳寿命预估，得到了桥壳疲劳寿命云图及最低疲劳寿命。针对上述桥壳疲劳寿命理论的计算结果，本文对装载机驱动桥桥壳的实际工况进行了动力学测试，对采集到的载荷数据进行了详细的分析，利用Nsoft的数据处理模块，对测试数据进行了雨流计数处理，得到其各采样点应力-时间历程的雨流/损伤直方图和损伤时间历程，并进行了基于实测载荷谱的桥壳疲劳寿命计算分析，最后与理论计算的结果进行了比较。本文对装载机驱动桥的动力学特性分析及桥壳疲劳寿命预测的研究为进一步进行驱动桥优化设计打下了基础,也为其它车辆机械零部件的动力学特性分析和抗疲劳设计提供了参考。更多还原

【Abstract】 Wheel loader is one kind of engineering machines about spading soil and transporting. Ithas the properties of rapid working speed, high efficiency and well maneuverability, so it hasbecome the main type of engineering machines for site operation. Drive axle is a key structuralcomponent of the transmission system of a wheel loader, accurate stimulating load analysis anddynamic response are the foundation of the dynamic characteristic analysis of drive axle. Byusing the virtual prototype technology to analyse and predict the dynamic response of the driveaxle transmission components, the transmission property can be improved, and the research anddevelopment cycle can be shorten. The drive axle housing sustains the load of the wheel loaderand transmit the load to the wheels, besides, it bears various forces and impacts both from roadand the vehicle itself. According to the theoretical study, the main style of forcing the ruin of theaxle housing is the fatigue failure which is caused by the long-term accumulation of damagecaused by the cyclic loading.Taking the drive axle of the wheel loader as the study object, this paper combines a specialproject of major technology in charge by the Zhejiang province science and technologydepartment, named "Study of key technologies and industrialization of the drive axle housing ofwheel loader"(2009C11111). In this paper, the analysis of dynamic properties and study of thefatigue life prediction of the axle housing of ZL50drive axle have been conducted. Firstly, useUG software to build the three dimensional models of all the parts of the drive axle and thenfinish the assembly. Also the theoretical analysis of both kinematics and dynamics have beencarried out. Considered the flexible effect between the axle housing and driver shaft, throughestablishing the mode neutral file of axle housing and drive shaft, they are regarded as flexiblebody. Then according to one kind of practical working condition of the wheel loader, build thespectrum between the tyre and road surface, obtain the rigid and flexible coupling multibodydynamic simulation model of the drive axle in Adams software to conduct the kinematic anddynamic simulation analysis. Finally some dynamic properties of the drive axle transmissionsystem can be got, and the results of simulation are basically identical with the theoretical ones. Because the working condition of the wheel loader is relatively complicated, this paper aims atthe dynamic analysis of wheel loader under the condition of passing through some kind ofemulational road surface, then conduct the dynamic safety analysis of the main loadedcomponents of the drive axle, obtain the dynamic load file, combine with the Ansys software tocarry out the finite element static analysis of the axle housing, then use the analysis results toobtain the stress spectrum of the axle housing. In the fatigue analysis module of Nsoft, thefatigue life prediction of the axle housing based on its finite element model has been made, thefatigue life nephogram and minimum fatigue life of the axle housing can be obtained.Aiming at the calculated results of the fatigue life theory above, the author has conductedthe dynamic test of the drive axle housing of wheel loader under practical working condition,and detailed analysis of the collected load data has been made. Using the data processing moduleof Nsoft, conduct the rainflow counting process of the measurement data, and rain flow/damagehistogram and damage time history of the stress-time history of all sample points can be got.Besides, carry out the calculation and analysis of the fatigue life of axle housing based on actualmeasured load spectrum, finally make comparison with the results of theoretical calculation.The analysis of dynamic properties of the drive axle on wheel loader and study of fatiguelife prediction of the axle housing in this paper have laid foundation for the further optimumdesign of the drive axle, also supply a reference of analysis of dynamic property and anti-fatiguedesign for the parts and components for other vehicles and machines.更多还原