摘  要本次毕业设计的题目是QY20汽车起重机悬挂系统设计。设计的汽车起重机的采用钢板弹簧非独立式悬挂作为前悬挂系统，后悬挂系统是采用平衡梁结构的钢板弹簧，也是非独立悬挂系统。设计的时候，我们应该首先确定悬挂系统的主要结构形式，然后确定悬挂系统的主要性能参数。在前悬挂系统的设计中应该首先设计钢板弹簧，材料和许用应力，以及悬挂系统方案布置的设计；还有选择适当的减震器。在后悬挂系统设计中主要设计合适的平衡梁结构的钢板弹簧，并对钢板弹簧的刚度和许用应力进行校核。73842

最后对悬挂系统进行了平顺性分析，判断所设计方案的悬挂系统是否满足汽车正常行驶时对平顺性的使用要求。在进行平顺性分析时运用了时域分析法，采用了两个自由度进行分析，然后利用软件进行计算，如果显示结果表明该设计方案提供的平顺性符合使用要求。那么就可以确定该设计对提高汽车起重机的动力性，经济性和操纵稳定性是有利的。

该论文有图14幅，表6个，参考文献39 篇。

毕业论文关键词：QY20汽车起重机  悬挂系统  钢板弹簧  平顺性

YL20-type crane suspension system

Abstract The title of this thesis is the design of front and rear suspension systems of QY20-type crane.

The front suspension system is the leaf spring, dependent suspension. The rear suspension system consists of the main spring and the helper spring and it is also dependent suspension. In the procedure of the design we made certain the structural style of the suspension system in the first, then we made certain the main parameters. In the design of the front suspension we designed the leaf spring firstly, material and allowable stress and the design of scheme , moreover the design of shock absorber. In the design of rear suspension we carried out the design of the main spring and the helper spring, specially the counting of distribution of angular rigidity between the main spring and the helper spring and the checking of the angular rigidity.

 Then there is the analysis of the comfort of the suspension system, determine whether the design of suspension system meet the requirements for the use of comfort when the car moving. Using the time domain analysis method to the car's comfort are analyzed, and the two degrees of freedom is analyzed, and then use software to calculate, if according to the results show that the design scheme to provide comfort to accord with the demand. You can determine if the design can make the motion of the crane, efficient and stable. Design and material is cheap, is able to improve on economic performance.

Key Words: QY20-type crane  Suspension Design  Leaf spring  Ride Performance

目  录

摘要Ⅰ

AbstractⅡ

目录-Ⅲ

图清单Ⅴ

表清单Ⅴ

变量注释表-Ⅵ

1 绪论 -1

 1.1 简述起重机- 1

 1.2 QY20起重机介绍4

 1.3 QY20起重机结构组成6

 1.4 课题简介 - 8

 1.5 小结  -9

2 QY20汽车起重机悬挂系统结构与分析10

 2.1 悬挂系统概论-10

 2.2 悬挂系统设计要求-12

 2.3 悬挂主要参数-12

 2.4 小结 14

3 前后悬挂系统设计-15

 3.1 前悬挂系统设计15

 3.2 后悬挂系统设计-21

 3.3 小结- 24

4 平顺性分析 -25

 4.1 平顺性定义- 25

 4.2 平顺性评价发布方法25

 4.3 平顺性的研究分析 25

 4.4 小结 30

5 结论31

5.1 本文完成主要任务31

5.2 结论31