Graduation Design (Dissertation) of Wuhan University of Technology

Design of Suspension System for Small Electric Scooter Vehicle

College (Department)： International Education College

Specialty amp; Class: Vehicle Engineering gj1303

Student Name： Chen Shihao

Tutor： Guo Wei

Statement of Originality

I solemnly declare that the thesis I submit is a piece of writing I completed independently based on my own research under the guidance of my supervisor. Except for the quotations, this paper does not include any writings published or completed by other individuals or groups. I am fully aware that the legal consequences of this statement are borne by me.

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Abstract

With the development of the automobile industry of motor vehicles on ride comfort, handling and stability as well as comfort and safety of the increasingly demanding, Vehicle Ride also closely related with the suspension. Therefore, the design of the suspension system has a practical significance.

The main design of the study is small electric car front and rear the suspension system of choice of hardware design, calculate the suspension stiffness, static and dynamic deflection. By damping and unloading of the largest absorber identified the main dimensions. Finally, the related design of the guiding mechanism is carried out. The selection of the design before and after the suspension, the use of independent suspension front suspension, rear suspension with non-independent suspension. Among them, the front suspension uses the current front suspension of the car, the popular Macpherson suspension. The shock absorber front and rear suspension adopts a double acting cylinder, the rear suspension arm drag. The design of the structure effectively improves the comfort and driving stability of the riding seat. CATIA software is used to model and draw the assembly drawings of the front and rear suspension and some main parts drawings.

Key words: suspension; ride comfort; design calculation

Catalog

Chapter 1 Introduction 1

1.1 The purpose and significance of the paper 1

1.2 Research status at home and abroad 1

1.3 Research contents and objectives 2

Chapter 2 Structural scheme analysis of suspension 3

2.1 Structure form of suspension 3

2.2 Non-independent suspension 3

2.3 Independent suspension 4

2.4 Front and rear suspension program selection 5

2.5 Main component selection 6

2.5.1 Elastic element 6

2.5.2Shock absorber 7

2.6 Auxiliary component 7

2.6.1 Horizontal stabilizer 7

2.6.2 Buffer block 8

Chaper3 Determination of main parameters of suspension 9

3.1 Static deflection of suspension 9

3.2 Dynamic deflection of suspension 10

3.3 Elastic characteristics of suspension 11

3.4 Design of elastic components in suspension 11

3.4.1 Spiral spring 12

3.4.2 Selection of material and allowable stress of spiral spring 12

3.4.3 Calculation and selection of spring parameters 13

3.5 Design of shock absorber 15

3.5.1 Shock absorber parameter determination 16

Chapter 4 Design of Independent Suspension Guidance Mechanism 20

4.1 Guidance design requirements 20

4.2 Arrangement of guide mechanism 20

4.2.1 Roll center 20

4.2.2 Roll axis 21

4.2.3 Center of inclination 21

4.3 Design of McPherson Suspension Guidance Mechanism 22

4.3.1 Analysis of force in guidance mechanism 22

4.3.2 Selection of axle Arrangement of Swing arm 23

4.3.3 Swing arm length 24

4.4 Influence of structural parameters on ride comfort 24

4.4.1 Suspension stiffness 24

4.4.2 Suspension damping 25

4.4.4 Non-sprung mass 25

Chapter 5 Conclusion 27

Acknowledgment 28

Reference 29

Chapter 1 Introduction

1.1 The purpose and significance of the paper

With the continued increase in the number of cars in the world today, the pollution of the environment and the use of resources have greatly increased, and the pressure on the environment and resources has continued to increase. With the rapid development of the automobile industry, a large number of internal combustion engine cars, a large number of emissions on the environment is terrible, and now the city center haze phenomenon has been very serious. Moreover, the use of internal combustion engine cars consume a lot of oil this non-renewable resources, which will lead to the shortage of oil resources, in this context, China vigorously promote environmental protection and energy conservation and sustainable development strategy. New energy vehicles in solving environmental and resource issues have many advantages. Compared to the internal combustion engine car, electric vehicles use electricity as energy, power system by the drive motor, unipolar reducer and control unit. One of the pure electric vehicle energy sources, energy economy, the use of basic pollution-free process, the advantages of small environmental damage, has been the attention of most countries, and vigorously develop, and as the impact of electric vehicle comfort and safety Suspension system, its research and development space will be greater.

1.2 Research status at home and abroad