【作者】 张杰；

【导师】 高峰；

【作者基本信息】 西安理工大学 ， 机械电子工程， 2008， 硕士

【摘要】 电火花铣削加工是二十世纪九十年代发展起来的一种新型加工工艺。它具备放电加工不受工件材料强度、硬度、韧性等物理性能制约的特点,同时又具有机械加工利用多轴联动对工件进行铣削加工的特点。在航空制造业、模具加工业等领域应用前景十分广阔。本文结合五轴联动电火花加工机床的研究与开发,以理论分析和工艺试验为基础,围绕电火花铣削加工的关键技术问题进行了探索性的研究。本文的主要研究工作如下:(1)分析五轴电火花机床的结构布局,确定布局方案。对摆动机构和电极夹头进行结构设计,分别提出不同的设计方案,并对各方案进行比较,选择最优方案作为最终方案。(2)根据圆柱形电极的损耗规律,建立了电极损耗的补偿模型,并进行与无补偿电火花铣削加工工件之间尺寸精度的对比实验。实验结果表明,本文提出的电极损耗补偿模型能够正确反映加工过程中电极的损耗状态,以补偿模型为依据进行损耗补偿的方法是可行的。(3)针对放电加工的特殊性,研究了电火花铣削加工的数控编程技术。在所建补偿模型的基础上,提出了典型轮廓、平面型腔及曲面加工的电极运动轨迹算法。根据五轴联动电火花加工机床的结构,在所建立机床坐标系统的基础上求解该机床的运动学逆解,得到了该机床各个坐标轴驱动量的数学表达式。为机床数控系统自动编程软件的开发提供了重要的理论依据。(4)总结了电火花铣削加工的工艺路线及电火花铣削加工工艺参数的选择原则,通过加工实验分析了加工精度和效率的影响因素,验证了所提出电极运动轨迹算法的正确性和UG CAM应用于电火花铣削的可行性。更多还原

【Abstract】 Electrical Discharge Milling is a new kind of processing technology since 1990s. Electrical Discharge Milling has not only the characteristics of Electrical Discharge Machining which can not be restricted by physical properties of workpiece materials, such as strength, hardness, toughness, but the features of milling workpieces using multi axes synchronously. Therefore, Electrical Discharge Milling has wide prospect of application in aeronautical and astronautical manufacturing industry, mold machining industry and so on.Based on the theoretical analysis and process experiments, the thesis investigates the key technical problems incorporating the research and development of five-axis linkage EDM machining tool. The main research contents are as follows:(1) The structural layout scheme of five-axis EDM machine tool has been designated by analyzing movement function. The structures of the swing mechanism and the electrode holders are designed. Several designs are proposed and compared each other. Finally, the optimal scheme is selected as the final decision-making scheme.(2) The compensating model with electrode wear is established on the basis of cylindrical electrode loss rule. The contrasting experiments of size precision are carried out between no-compensating and compensating EDM Milling. The experimental results indicate that the compensating model can reflect the electrode loss status accurately during processing and the compensating method of electrode wear proposed is feasible.(3) Accounting for the particular properties of discharge machining, NC programming technology in EDM Milling is studied. On the basis of the compensating model presented, the thesis puts forward the path generating algorithm of the electrode movement on typical two-dimensional profile、plane pockets and surface machining. The solution of inverse kinematics of five-axis EDM machining tool is achieved based on the coordinates system of machine tool. The mathematical expression of driving value of each axis is deduced out, which provides an important theoretical foundation for developing automatic programming software for CNC system of EDM machining tool.(4) The machining process route and the selecting principles of processing parameters in EDM Milling are summarized. Through the machining experiments, the influencing factors of machining accuracy and efficiency are analyzed, and the correctness of the algorithm on electrode movement path proposed and the feasibility of UG CAM application in EDM Milling are verified.更多还原