摩托车发动机顶置凸轮机构的分析与的分析研究.pdf

华中科技大学硕士学位论文摘要凸轮机构的设计在整个内燃机设计中有很重要的地位,特别是对于高速小型汽油机。,对于凸轮型线设计,特别对凸轮升程的算法进行了改进。文中对设计凸轮型线采用了响应谱的方法进行分析。对于摩托车发动机项置凸轮机构进行了运动模型分析,将单自由度和多自由度模型应用于变摇臂比的顶置凸轮机构。此外,对于摇臂不仅进行了传统的!!!三兰廛袭坌堑-而且还进行了三丝接触直E巳五镒丘研究。文中以嘉陵工业集团的CUBl00摩托车发动机配气机构为例进行了计算研究。采用上述方法,改进了原凸轮的设计,获得了性能指标更好的凸轮型线和机构设计参数。提高了凸轮型线的丰满系数和最大升程,从而大大提高了气门的流通面积。用多质量模型找到了原凸轮机构的弹簧碰圈,并在新的设计中消除了这种现象。用三维有限元分析了摇臂的受力分布,找到了应力集中的地方,并改进了摇臂设计,减小了系统的最大应力,保证了结构的强度要求。本文还开发了凸轮机构设计软件,采用Visual !!ji￡泣让语言编写出Windows应用程序·该软件为凸轮设计人员的研究提供了良好的人机对话界面,设计采用模块化思想为今后的凸轮机构设计扩展功能打下了基础。斑讯醐秒三秒元秒华中科技大学硕士学位论文 Abstract The design ofthe valve train isvery important inthewhole design of bustion Engine,especially ofthe small high—speed paper hascalculated andanalyzed theover—head valve train on themotorcycle、Ⅳitll puter design. Firstly pleted theprogram ofthedesign ofvaries profile ofcam,in particular improved themethod ofcalculating the theauthor discussed the design profile withdynamic response thepaper analyzed putation oftheover.-head valve trainwith varies ratioofrockerusingone··degree and multi·degree the author not only calculated the stress intherocker with Hertz method,but also discussed thisproblem inthe 3-D contact FEM method. This paper iS based On thevalve trainofCUBl00 of JIA LING GROUP C0,,LTD, With themethod above,the author improved thedesign ofprofile oftheoriginal cam and obtained good design ofimpro'Ving thecam profile coefficient and raising themax liRofcam new one increases the area isfound that theoriginal valve train has thephenomena ofspring contact with muti—mass—model, and the new one eliminate 3-D FEM method,this paper has notonlyanalyzed the stress distribution inrocker,and also found out where has stress improved rocker decreases themax stress in themodel and ensures therocker’ thispaper,the author developed thecamdesign software,which was base