摘 要

本文选择长安福特新世代全顺短轴多功能轻客为研究对象，参考相关汽车设计指导书籍和文献，结合国内外相关设计和研究方法，设计了一款商用车传动轴总成模型，利用UG NX 12.0软件建立该传动轴的三维模型并进行运动仿真，并利用ANSYS Workbench 软件对传动轴进行有限元分析和优化。

根据给定的原始参数，结合商用车传动轴实际使用情况，确定了传动轴的布置形式和主要零件的设计参数，校核了设计部件的极限应力指标，完成了各项零件三维实体模型建模和总体装配。

运动仿真分析表明，各部件均能在约束条件下自由转动。并且整体能保持等速运转，将输入端的转矩准确地进行输出。但由于滑动花键轴上的往复运动，传动轴装配体在高速转动时稳定性较差，存在一定的振动现象。

有限元静载荷分析表明，传动轴轴管中等效应力最大值136.86 MPa，出现在轴管固定端；花键轴等效应力最大值63.23 MPa，剪切应力最大值25.40 MPa；十字轴上等效应力最大值位于轴颈根部，为215.2 MPa，剪切应力主要分布在Y轴上，最大值同样位于轴颈根部，为58.91 MPa。分析得到的应力最大值与理论计算结果基本一致。验证了设计计算的正确性和有限元分析方法在传动轴设计过程中的可行性。

模态分析表明，传动轴轴管七至十阶模态的固有频率分别为313.63Hz和828.04Hz；传动轴总成一至三阶整体约束模态的固有频率分别为116.84 Hz、121.54Hz和304.79Hz，四至六阶的固有频率为318.61Hz、577.2Hz和577.64Hz。固有频率的数值与汽车正常行驶时车架的固有频率（10-50Hz）差距较大，共振现象不容易发生。

优化设计中，将中间支承轴承修改为双列圆锥滚子轴承，缓冲了滑动花键轴的轴向运动，提升了高速运转时的稳定性。借助拓扑优化分析结果，修改了十字轴轴颈内油道尺寸。优化后模型最大应力减小了7.11%；部件的体积和质量减小了4.27%，成功地改善了十字轴的受力情况，减小了十字轴的重量，达到了轻量化的目的。

关键词：传动轴总成；传动轴设计；有限元分析；拓扑优化

Abstract

In this paper, a commercial vehicle was selected as the research object, and a commercial vehicle transmission shaft assembly model was designed with reference to relevant automobile design guide books and documents, combined with relevant design and research methods at home and abroad. UG NX 12.0 software was used to establish a three-dimensional model of the drive shaft and perform motion simulation, and ANSYS Workbench software was used to perform finite element analysis and optimization of the drive shaft.

According to the given original parameters, combined with the actual use of the commercial vehicle drive shaft, the layout of the drive shaft and the design parameters of the main parts were determined, the ultimate stress indicators of the designed components were checked, and the 3D solid model modeling of each part was also completed to complete the overall assembly.

Motion simulation analysis showed that all components can rotate freely under restraint conditions. The whole shaft can maintain constant speed operation, accurately output the input torque. However, due to the reciprocating motion on the sliding spline shaft, the stability of the transmission shaft assembly during high-speed rotation was poor, and there was a certain vibration phenomenon.

The finite element static load analysis showed that the maximum equivalent stress in the shaft tube of the transmission shaft was 136.86 MPa, which appeared at the fixed end of the shaft tube. The maximum equivalent stress of the spline shaft was 63.23 MPa, and the maximum shear stress was 25.40 MPa. The maximum value of the equivalent stress on the cross shaft was 215.2 MPa at the base of the journal, and the shear stress was mainly distributed on the Y axis. The maximum value was also 58.91 MPa at the base of the journal. The maximum stress value obtained by the analysis was basically consistent with the theoretical calculation result, which verified the correctness of the design calculation and the feasibility of the finite element analysis method in the design process of the transmission shaft.

The modal analysis showed that the natural frequencies of the seventh to tenth modes of the transmission shaft tube were respectively 313.63 Hz and 828.04 Hz. The natural frequencies of the first to third order overall constrained mode of the drive shaft assembly were 116.84 Hz, 121.54 Hz and 304.79 Hz, and that of the fourth to sixth orders were 318.61Hz, 577.2Hz and 577.64Hz. The value of the natural frequency was quite different from the natural frequency of the frame of the car (10-50Hz) when the car is running normally, and the resonance phenomenon was not easy to occur.

In the optimized design, the intermediate support bearing was modified to a double-row tapered roller bearing, which buffered the axial movement of the sliding spline shaft and improved the stability during high-speed operation. With the help of topology optimization analysis results, the size of the oil passage in the cross journal was modified. After optimization, the maximum stress of the model was reduced by 7.11%; the volume and mass of the components were reduced by 4.27%, the purpose of light weight was achieved by successfully improving the stress condition of the cross shaft and reducing the weight of the cross shaft.

Keywords: Drive shaft assembly; Drive shaft design; Finite element analysis; Topology Optimization

目录

摘 要 I

Abstract II

第1章 绪论 1

1.1 选题的研究目的和研究意义 1

1.2 国内外汽车传动轴研究现状 1

1.2.1 国外研究现状 1

1.2.2 国内研究现状 2

1.3 论文研究的基本内容、目标及技术方案 3

1.3.1 研究的基本内容 3

1.3.2 研究目标 3

1.3.3 技术方案及措施 3

1.4 本章小结 5

第2章 传动轴布置方案选择 6

2.1 长安福特新世代全顺短轴多功能轻客原始数据 6

2.2 传动轴总成的结构特点和基本要求 7

2.3 传动轴总成主要结构形式及其选择 8

2.4 中间支承的选择 10

2.5 本章小结 10

第3章 传动轴总成的设计 12

3.1 多万向节传动轴夹角设计 12

3.2 传动轴轴管设计 14

3.3 传动轴花键设计 17

3.3.1 主传动轴花键设计 17

3.3.2 中间传动轴花键设计 19

3.4 十字轴设计 21

3.5 滚针轴承选用 22

3.6 万向节叉设计 24

3.7 深沟球轴承选取与轴承座设计 25

3.8 连接螺栓强度校核 27

3.9 本章小结 28

第4章 传动轴总成UG三维模型建立 30

4.1 UG三维建模相关理论 30

4.1.1 UG软件简介 30

4.1.1 传动轴总成建模流程 30

4.2 主要零件仿真模型创建 30

4.2.1 轴管模型的建立 30

4.2.2 十字轴模型的建立 31

4.2.3 万向节叉模型的建立 32

4.2.4 凸缘叉-联轴器模型的建立 32

4.2.5 花键轴模型的建立 33

4.2.6 轴承座模型的建立 36

4.2.7 轴承的调用 38

4.2.8 中间支承花键轴轴管模型的建立 39

4.2.9 伸缩套轴管与中间支承花键套模型的建立 39

4.3 模型装配 40

4.4 运动仿真 43

4.5 本章小结 45

第5章 传动轴总成静载荷和模态分析 46

5.1 ANSYS有限元分析软件简介 46

5.2 传动轴总成静载荷分析 46

5.2.1 基于ANSYS的有限元模型生成 46

5.2.2 中间传动轴有限元受力分析 47

5.2.3 花键轴齿侧有限元受力分析 49