【作者】 何王勇；

【导师】 杨代华；

【作者基本信息】 中国地质大学 ， 机械设计及理论， 2003， 硕士

【摘要】 喷油嘴偶件针阀体是柴油发动机上的重要零部件，它的加工质量优劣将直接影响到柴油发动机的油耗以及废气的排量。对于小孔径的喷油嘴，特别是直径为4mm的P系列喷油嘴的中孔座面的磨削，一直采用进口的数控磨床加工。但由于一台高精度进口数控磨床约需400万人民币，使得一些制造厂家望而生畏。 本文主要论述了在利用即将报废的液压中孔座面磨床本体基础上，使用国产开放型数控系统，经二次开发技术，成功地将其改造成性能优良的数控磨床的具体方法。更为重要的是用在其改造上费用只有进口设备的1／5，而加工质量与进口设备相当，完全满足了高精度小孔径喷油嘴的加工工艺要求。 论文首先分析了针体阀的加工工艺要求，以及国内外目前的加工工艺现状，阐述了利用旧机床进行数控化改造的意义。在经典自动控制理论的指导下，制定了使用数控系统的全闭环控制方式来改造液压中孔座面磨床的具体实施方案。接着文章围绕设备的改造全过程，选择了能满足项目要求的各控制系统部件，设计了喷油嘴针阀体加工的PLC控制软件，以及数控加工程序，并经抗干扰措施和参数整定技术处理，保证了机床性能的稳定和优化。同时创新性的提出了“跳选段”新功能，满足了用户加工的各种要求，完成了整个项目的改造任务，实现了加工过程的全自动化。本文最后对改造的机床与进口设备进行了对比，并对实际加工的零件进行了测试，产品合格率达到94％，从而填补了国内高精度小孔径喷油加工的空白。 该项目的胜利完成。一方面，打破了“高精度机床的数控装置只选用国外数控系统”的惯例，避开了选用国外数控系统在短时间内难以二次开发的难题，解决了喷油嘴中孔座面加工中高精度的加工技术要求问题和方便操作问题。另一方面，作为高新技术的数控化改造技术将会为我国机械制造业缩小与发达国家间差距，提升企业数控化率进程，改变落后生产现状，提供了一条即符合国家产业政策又切实可行的途径。数控化改造具有广阔的市场前景和重大的经济、社会效益。更多还原

【Abstract】 The valve of ejection nozzle is an important part in the diesel engine; its processing quantity will directly affect the amount of the oil usage and the exhaust let off by diesel engine. For small aperture ejection nozzle, especially to the P serial type that the center hole diameter is 4mm, its center hole and inner cone is always adopting imported Numerical Control machine to grind. But an imported Numerical control grinder needs about 0.5 million dollars, most domestic companies can not offer it.In the paper, it mainly discusses how through redevelopment technique on the homemade open type Numerical Control System to successfully reconstruct an old hydraulic injection nozzle center hole and inner cone grinder, and make this declining machine obtain excellent capability. The important is that the expenses used on technical reconstruction only is 1/5 of an new importing equipments, but its processing quantity is almost equal to the importing equipments, completely can satisfy with the rigor craft request of the ejection nozzle’s precision.At first, The paper analyses the craft request on the valve of ejection nozzle processing, and the new status on the domestic and international processing, then puts forward the significance that making use of Numerical Control technology to reconstructing the old machine. Under the classic automatically control theorist’s leading, the thesis establishes idiographic practice methods that using closed loop open type Numerical Control system to reconstruct the old hydraulic injection nozzle center hole and inner cone grinder. The paper, being around with the whole technical reconstruction process, chooses each parts of control system that can satisfy with request, and designs PLC software controlling the grinding process, and G_code grinding program. What is more, through taking anti- interference measure and parameter optimizing settle, it guarantees the machine function’s stability and optimizing. At the same time, in the paper ,it brings up a creative new "skipping the chosen row " function , satisfying the needs of the grinding procedure, completing the whole item mission of reforming, and realizing the whole grinding process automatization. At the Last of the paper, by contrasting the performance of the reconstructed machine with importing machine, and measuring the produced workpiece, it finds that the rate of eligible production attain to 94 percent, and shows that the reconstructed machine is no less than the imported machine in performance, which supplies a gap on tooling small aperture ejection nozzle.This item successfully completed under scheduled. One hand, it breaks the customary practice of only using foreign Numerical Control System to equip with high precision machine,escapes the hard problem that it is difficult to self redevelop in limited time by using foreign Numerical Control System, and resolves the problems that it needs convenience in manipulation and high precision in grinding. On the other hand, Numerical Control technical reconstruction, as a high new technology, it provides a both matching the national policy and reliable method for our reducing the margin between developed countries, advancing the pace owning Numerical Control machine, and changing the behind productive status. It has the vast of market foreground, and immense economic benefits social benefits.更多还原