395468$wlun86$汽车发动机缸盖零件毕业设计.doc

（2009届） 本科毕业设计 题 目 名 称： 汽车发动机缸盖零件 机加工工艺与夹具设计 学 院（部）： 机电工程学院 专 业： 机械设计制造及其自动化 学 生 姓 名： 摘 要 缸盖是内燃机零件中结构较为复杂的箱体零件，也是关键件，其精度要求高，加工工艺复杂，且加工质量直接影响发动机整体性能，对于内燃机气缸盖制造。随着科技的发展，汽车制造商们对发动机缸盖的机加工越来越重视，缸盖的机械加工工艺技术也在不断地进步。本缸盖与缸体合成球形燃烧室，缸盖上有同轴的凸轮轴孔，进、排气阀座与导杆孔，火花塞孔等做其尺寸精度、几何形状精度和相互位置精度，以及各表面质量均影响发动机的性能与工作寿命，是一个关键。 为保证缸盖的加工精度要求，需要拟定合理的机械加工工艺路线。工艺路线决定了各表面的加工方法、工序数目和各工序所用的基准，之后具体编排各工序的顺序，包括机械加工工序、热处理、表面处理、检验，以及各种辅助性工序，安排工艺路线必须合理，符合客观规律。 机床夹具是机床上用来装夹工件的一种装置，其作用是使工件相对于机床或刀具有一个正确的位置，并在加工过程中保持这个位置不变。工件装夹的实质是在机床上对工件进行定位和夹紧，装夹的目的是通过定位和夹紧使工件在加工过程中始终保持正确的加工位置，以保证该工序所规定的加工技术要求。 关键词：缸盖，技术，工艺，定位 ABSTRACT The cylinder cover is in the internal combustion engine components the structure more complex box body components, also is the key, its precision requests high, the processing craft is complex, also the processing quality directly affects the engine overall performance, regarding internal combustion engine cylinder cover or cap manufacture. Along with the technical development, the automobile manufacturers more and more take to the engine cylinder cover machining, the cylinder cover machine-finishing craft technology also in unceasingly progresses. This cylinder cover and the cylinder body synthesis spherical combustion chamber, on the cylinder cover has the coaxial cam shaft hole, enters, the exhaust valve seat and the guide rod hole, the spark plug hole and so on makes its size precision, the set shape precision and the mutual position precision, as well as various surface quality affects the engine the performance and the working life, is a key. Be to ensure that the treating accuracy that the jar covers up with demands a handicraft , needs to design rational machine work. The handicraft route has decided criterion used by every surface job operation , working procedure number and every working procedu