Graduation Design (Dissertation) of Wuhan University of Technology

Design of Volkswagen MAGOTAN Steering system

(School): International Education College

Specialty amp; Class: Vehicle engineering gj1302

Student name: Li Guozhen

Tutor: Du Xiaofang

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.

Signature of the author: 李果真

Date:2017.5.29

Copyright Letter of Authorization to The Dissertation

The author of this dissertation fully understands provisions stipulated by this school on keeping and using dissertations. The author agrees that the school can reserve and send photocopies and electronic versions of this thesis to relevant departments or institutions managing dissertations. This thesis can be read and borrowed. I hereby authorize excellent provincial institutions appraising bachelor dissertations to incorporate all or any part of this dissertation into relevant databases for retrieval, as well as to preserve and compile this dissertation by photocopying, scanning or reprinting it in a reduced format.

This dissertation is: 1. Confidential until(year) and then this authorization letter will apply. 囗

2. Non-confidential. 囗

(Please tick "√" the corresponding box above)

Signature of the author:李果真 Date;2017.5.29

Signature of the tutor: Date

(Not: this page shall be stapled together with this dissertation as its title page)

Abstract

This topic is the design of the steering system of a car with the the rack and pinion steering gear as the center example. There are several stages, the first one is the overall structure of the vehicle parameters on the impact of steering, the second is the choice of the mechanical steering gear. The third being the gear and rack arranged reasonably to match the correct gear ratio and Strength requirements.

The fourth is the power steering mechanism design and fifth is the trapezoidal structure design. Therefore, this topic is based on the above requirements. The factors are to study the use of the steering wheel drive, drive the gear wheel steering wheel through the universal joint, drive the steering gear shaft rotation, steering gear shaft

Steering gear meshing and the steering rack linear motion to achieve high performance steering. The realization of the steering structure is simple and compact with the axial size being short, and the number of small parts that can increase the advantages of the power so as to achieve the stability and sensitivity of the car steering. In this paper, the design of the geared gear rack and the check of the steering gear shaft are mainly carried out. The main methods and theories are designed with the experience parameters of the automobile design and the course content of the mechanical design. The results meet the strength requirements which are safe and reliable.

Key Words: steering system; EPS; pinion and rack; tie rod

Content

Statement of Originality 2

Copyright Letter of Authorization to The Dissertation 3

Abstract 4

Content 5

1. Introduction 7

1.1 Overview of Automotive Steering System 7

1.1.1 Mechanical Steering System 8

1.1.2 Hydraulic Power Steering System 8

1.1.3 Electronically Controlled Hydraulic Power Steering System 9

1.1.4 Electric Power Steering System 10

1.1.5 Steering-By-Wire 12

2. Steering System Design Overview 14

2.1 The Requirements of the Steering System 14

2.2 Steering Control Mechanism 14

2.3 Steering Linkage 15

2.4 Steering Devices 16

2.5 Turning Angle and Minimum Turning Radius 16

3.Selection of Steering System and Determination of Main Parameters 18

3.1 Selection of Steering System 18

3.1.1 Steering Wheel 18

3.1.2 Steering Axle 18

3.1.3 Steering Gears 19

3.1.4 Steering Trapezium 19

3.2 Main Performance Parameters of Steering System 20

3.2.1 Steering System Design Prerequisites 20

3.2.2 Efficiency of Steering System 20

3.2.3 Positive efficiency of the steering gears 20

3.2.4 Reverse Efficiency of the Steering Gear 21

3.3 Transmission Ratio Variation Characteristics 22

3.3.1 Steering gear ratio 22

3.3.2 Force Transmission Ratio and The Relationship Between The Steering Angle Ratio 22

3.3.3 Steering Angle Ratio Selection 23

3.4 Steering Gear Transmission of The Transmission Gap △ t 24

3.5 The Total Number of Rounds of the Steering Wheel 25

4.Analysis and Design of Mechanical Steering Gear 26

4.1 Rack and Pinion Steering Gear 26

4.2 Other Kinds of Steering Gear 28

4.3 The Principle and Arrangement of Gear and Rack Type Steering Gear, The Choice of Structure 29

4.4 Determination of Parameter 30

4.5 Calculation Process 30

4.5.1 Calculation of Side Deflection Angle of Steering Wheel 30

4.5.2 Steering Parameter Selection 30

4.5.3 Select The Rack and Pinion Material 32

4.5.4 Strength Check 32

4.5.5 The basic parameters of the rack and pinion are shown in the following table: 34

4.6 Structure Design of Gear Shaft 34