【作者】 魏力；

【导师】 贾振元； 刘巍；

【作者基本信息】 大连理工大学 ， 机械电子工程， 2012， 硕士

【摘要】 在工业装备中微细结构日益增多,微细结构加工需求随之增大。微细电火花铣削加工技术在微细结构加工方面具有极大的技术潜力和优势,具有材料适用范围广、无宏观切削力等特性。但是,微细电火花铣削加工技术也存在着诸多技术难题：微小的放电能量和放电间隙造成放电状态不稳定,加工过程中易出现短路现象,加工过程难于准确控制,加工效率较低；由于加工过程中电极不断损耗,精确的电极补偿与合理的轨迹规划相结合才能完成微小三维结构加工。因此,解决微细电火花铣削加工中的短路问题,并且进行精确的电极补偿与轨迹规划是微细电火花铣削加工方法中的关键问题。针对微细电火花铣削加工过程中出现的电极与工件间的短路现象,通过分析微细电火花铣削加工特性和短路产生原因,本文提出了一种基于正方形约束的插补算法和基于动态周期的进给控制方法,并为该插补算法所产生的插补数值设计了基于位模式的存储结构。该插补算法与进给模式相结合,充分利用了微细电火花铣削加工的特性,解决了加工过程中出现的短路问题。在解决短路问题的基础上,本文进行电极补偿实验和三维结构加工的轨迹规划研究。以等量补偿和分层铣削加工理论为基础,通过工艺实验确定了电极补偿参数,并将电极补偿与三维结构轨迹规划相结合,设计出三维结构的加工轨迹,实现自动补偿加工。基于以上研究,最终开发出了微细电火花铣削加工机床控制软件,将基于正方形约束的插补算法与动态周期的进给控制方法集成于系统中,并将铣削加工过程中的加工状态、电极补偿参数、手动控制和加工参数调整等集成于系统中,同时对运动控制卡中的PID控制系统进行参数调节,满足伺服运动的灵敏性和精确度要求,实现了对机床三轴联动的精确控制。通过实验验证,本文提出的基于正方形约束的插补算法和动态周期进给控制模式,以及本文开发的微细电火花铣削加工控制软件,能够在微细电火花铣削加工过程中避免电极与工件之间发生短路,将微细电火花铣削加工效率提高了30%。在三维微小结构加工实验中,利用本文确定的补偿参数和轨迹,实现了分层铣削加工过程中电极自动补偿,能够一次性加工完成三维微小结构。更多还原

【Abstract】 There are more and more Mico-constructs in industry equipment. It demands more machining methods. Mico-EDM milling has great advantage and potential ability to machine Mico-constructs. Micro-EDM milling is a kind of manufacturing method of non-contact between tool and workpiece. It can machine many kinds of material and no cut force. But some weak points such as discharge energy, discharge distance and unstable discharge state make it hard to control the machining process and to get effective method. It is also difficult to meet the accuracy for the electrode corrosion. The electrode compensation is important to the accuracy. Therefore, it is necessary to solve short circuit and make accurate compensation and path plan.This paper present a new interpolation method based on square constraint which can preclude short circuit in Mcro-EDM milling. There is also a new storage structure for the NC code. Based on the new interpolation method, this paper researched the feed method and present available period feed method. Meanwhile, a lot of machining experiments have been done to find the optimal electrical parameter. In the machining experiments, the new interpolation method combined with the new feed method can solve the short circuit problem and enhance the efficiency largely. The optimal electrical parameter can enhance the efficiency more. Based on the compensation parameter, this paper researched the3D’ path plan and designs3D path with automatic compensation. Based on the researches above, this paper developed a numerical control software for Mico-EDM milling machine. The software contains control method, machining state display, compensation method, manual control and parameter adjustment. It can control movement of motors and platform to meet the accuracy through PMAC.In the experiments, the software can connect well with hardware and the accuracy can meet the design requirement. As no short circuit in the machining process, the machining efficiency was improved by30%. Also, using this system, the micro-3D structure can be machined in one time with automatic compensation.更多还原