摘要配气机构是内燃机的重要组成部分，它是由气门组、气门传动组、凸轮轴传动机构三部分组成。它的功能是实现换气过程，即根据气缸的工作次序，定时地开启和关闭进气门、排气门，以保证气缸吸入新鲜空气和排除燃烧废气。其设计的合理不合理接关系到内燃机的经济性能、动力性能、排放性能及工作的可靠、耐久性。ND485柴油机采用下置式传动形式，由凸轮、挺柱、推杆、摇臂、调整螺钉等组成。因为发动机进排气过程由配气机构控制,直接影响着发动机的性能，所以它是衡量发动机可靠性的指标之一。随着内燃机高功率、高速化的发展，其性能指标的要求也越来越高，为了能够使其在高速运行的条件下仍然能够工作的平稳、可靠，因而对配气机构有了更高的要求。52564

毕业论文关键词：柴油机；配气机构；凸轮型线

ABSTRACT   The valve train is one the most important mechanisms in a internal combustion engine.It is set by the valve, valve transmission group, camshaft drive mechanism consists of three parts.Its function is to achieve the ventilation process, that is based on the work order of the cylinder, timed to open and close the intake valve and exhaust valve to ensure fresh air and remove the suction cylinder combustion exhaust gas.The design of a reasonable relationship to the internal combustion engine connected to unreasonable economic performance, power performance, emissions performance and work reliable durability.ND485 diesel engine mounted under the drive forms, by the cams, tappets, push rod, rocker, adjusting screws and other components.Because the engine intake and exhaust valve train control process consists of a direct impact on the performance of the engine, so it is one of the indicators to measure engine reliability.With the high engine power, high-speed development, its performance requirements are getting higher and higher, in order to enable it to run at high speed under the conditions still able to work smoothly and reliably, and thus have higher gas distribution mechanism requirements.

Key words:Internal combustion engine; Valve train; Cam profile

目 录

第一章 绪论 1

1.1 本课题背景 1

1.2 本课题研究的目的与意义 1

1.3 配气机构的研究历程和现状 2

1.4 本课题主要研究内容 3

第二章 配气机构总体布置的设计 4

2.1 配气机构设计要求 4

2.2 气门的数目、布置 4

2.3 凸轮轴的布置和传动方式 4

第三章 配气机构的零件和组件的设计计算 6

3.1 气门组的设计 6

  3.1.1气门的设计 6

3.1.2 气门座圈的设计 11

3.1.3气门导管的设计 12

3.1.4气门弹簧的设计 13

3.2凸轮轴的设计 19

3.3 几何凸轮的设计 20

3.4挺柱的设计 22

3.5推杆的设计 25

3.6摇臂的设计 26

第四章 基于SolidWorks的三维建模 30

4.1 SolidWorks软件简介