摘 要

为了模拟发动机高压燃油喷射系统，开发了一款基于压缩空气加压的燃油喷射实验装置。首先，对实际发动机燃油喷射系统进行系统分析，对实验常用的模拟方式进行了分析与比较，在优缺点明确以及制造成本和加工难度可以接受的情况下，确定出此设计方案。本设计包括：气动系统设计、燃油供给系统设计、零部件设计以及标准件选定。本方案采用大口径气缸提供动力，推动缸径较小的油缸，燃油密封在油缸活塞一端，实现最大大于20MPa的喷射压力。

本设计具体包括：对油缸的缸头、缸体、端盖、活塞、活塞杆、导向套进行设计，同时设计了防尘装置和密封装置等。根据各部件的构造，结合行业标准，设计出了气缸与油缸的固定支撑件，并进行了强度校核。此外，还选用了与设计油缸配套的并能达到实验需求的气缸，以及气缸与油缸的连接件。以上各部件构成了此套实验装置的类共轨燃油加压系统。此实验装置的燃油喷射系统采用现有的缸内直喷发动机喷油嘴，喷油时长及喷油频率由汽车发动机电脑和信号发生器控制，油管和各部位管接头选用强度符合实验需求的标准配件。气缸内气源由空气压缩机提供。

系统各部件设计完成后，对各零部件及整体结构进行建模，并进行仿真分析，同时完成图纸设计。

关键词：高压共轨、燃油喷射、增压系统、油缸设计

Abstract

In order to simulate the engine high pressure fuel injection system,a fuel injection experiment based on compressed air pressure was developed.Firstly,analyzed the actual engine fuel injection system systematically,and analyzed and compared the simulation methods commonly used in the experiment.The design scheme is determined under the condition that the advantages and disadvantages are clear and the manufacturing cost and processing difficulty are acceptable.The design includes: pneumatic system design, fuel supply system design, component design and standard parts selected. The program uses large diameter cylinder to provide power to promote the cylinder smaller cylinder, fuel sealed at the end of the cylinder piston to achieve greater than 20MPa injection pressure.

The design specifically includes: the cylinder head, the cylinder, the cover, the piston, the piston rod, the guide sleeve , while design the dust-proof devices and sealing devices. According to the structure of each component, combined with industry standards, designed the fixed support of the cylinder and the fuel tank , and check the strength. In addition, also selected the cylinder which can be work together with the fuel tank and can meet the needs of the experiment, and the connection of the cylinder with the fuel tank. The above components constitute the set of experimental devices of the common rail fuel pressure system. The fuel injection system of this experimental device adopts the existing in-cylinder direct injection engine injector, the fuel injection time and the fuel injection frequency are controlled by the automobile engine computer and the signal generator. The tubing and the parts of the pipe joint are selected to meet the requirements of the experimental standard Accessories. The air supply in the cylinder is provided by the air compressor.

After the design of the components of the system is completed, modeling the components and the overall structure,and simulation analyzed,at the same time to complete the drawings design.

Key Words：high pressure common rail, fuel injection, pressurization system, cylinder design

目 录

第1章 绪论 1

1.1 现状、目的及意义 1

1.1.1 国内外发展现状 1

1.1.2 研究的目的 1

1.1.3 研究的意义 1

1.2 研究内容与目标 1

1.2.1 研究的内容 2

1.2.2 研究的目标 2

1. 燃油喷射系统方案的选用 3

2.1 发动机共轨系统的结构 3

2.2 实验用燃油喷射系统备选方案 4

2.2.1 利用高压油泵加压 4

2.2.2 利用蓄能器改装类共轨燃油喷射系统 4

2.2.3 自制类蓄能器制作类共轨燃油喷射系统 6

2.2.4 利用大缸径气缸推动小缸径油缸实现加压 6

2.3 实验用燃油喷射系统方案的确定 8

1. 燃油喷射系统设计 9

3.1 气动装置的选用 9

3.2 油缸的设计 12

3.2.1 缸筒的设计 12

3.2.2 活塞组件的设计 14

3.2.3 导向套的设计 17

3.2.4 缸头和端盖的设计 19

3.3 固定件及连接件的设计 21

3.3.1 固定件的设计 21

3.3.2 固定件的仿真分析 22

3.3.3 连接件的设计 25

3.4 燃油喷射装置的选用 27

第4章 总结 28

参考文献 29

致谢 30

第1章 绪论

1.1 目的、意义及现状

1.1.1 设计的目的