高速走丝电火花线切割数控技术应用研究

【作者】 罗智恒；

【导师】 郭钟宁；

【作者基本信息】 广东工业大学 ， 机械制造及其自动化， 2004， 硕士

【摘要】 电火花线切割加工技术具有切削力小，容易加工复杂、精密和高硬度零件的特点，因而在模具制造、成型刀具加工、难加工材料及精密复杂零件的加工中占有重要的地位。高速走丝电火花线切割机床在我国的应用十分广泛，经过数十年的发展已经到达了比较成熟的水平，但是，目前高速走丝线切割机床的数控技术并不完善，而数控系统是机床的核心部分，其性能直接影响机床加工精度和稳定性，同时也决定了机床的使用范围和复杂零件的加工能力。随着开放式数控技术逐渐成为数控发展的主流，电火花线切割数控系统同样应该朝着开放式的方向发展，建立开放式的线切割数控系统有着十分重要的现实意义。 从这个角度出发，本文研究了高速走丝电火花线切割机床的数控系统，采用PC+运动控制卡的模式，并设计和分析了该系统的软硬件结构。本文主要就数控系统中的三个部分进行了研究：首先，研究了数控系统的控制软件，包括根据3B代码生成相应的图形、数据处理、模拟仿真，与硬件设备通信及数控辅助功能等几个方面。其次，选择AVR单片机作为运动控制卡核心并研究其相关的应用技术，主要包括扩展单片机外部数据存储器的方法，在不改变控制卡电路板的情况下实现几种RAM芯片的互换；同时还就单片机驱动数控工作台、控制步进电机加减速的问题进行了研究。最后，研究了如何利用CPLD实现PC与单片机之间通过ISA总线进行数据传递，并设计出控制卡的电路，为整个数控系统提供了硬件基础，同时采取了一些抗干扰措施以提高系统的稳定性。更多还原

【Abstract】 The Wire Electric Discharge Machining (WEDM) shows a relatively small cutting force compared to traditional machining, so it is suitable for the machining of parts with complex shapes, high precision and hardness. It plays an important role in mould industry, tool industry, and special machining field et al. Wire electric discharge machining with high travelling speed (WEDM-HS) machine tools are widely used in China. By decades of developments, it has reached a mature level. However, the NC part, which is the core module of the WEDM-HS needs to be improved. Because the performance of NC will direct affect the machining precision and stability, and it also decides the application scopes and machining ability of complex parts, much attention should be paid on it. When the Open Architecture Numerical Control is becoming the future of the numerical control technology, the numerical control system for WEDM should follow the stream. So it has important significance to build an Open Architecture Numerical Control system of WEDM.From this point of view, this paper discusses the numerical control system for WEDM-HS. The construct mode of OANC system adopted in the research is "PC plus Motion Control Board", and the soft and hard structure of this system have been designed and analyzed. The research on numerical control system includes three parts:First, the software of the system has been studied, including generating process drawing according to the machining code (3B), data processing, simulation of machining process, communication with hardware and other assistant functions of numerical control etc.Second, selecting AVR microprocessor as the core of Motion Control Board and studying the relevant application technology, mainly consists of the methods to expand microprocessor exterior data memorizer, realizing the exchange of several kinds RAM CMOS chips without change the circuit board, some techniques how the microprocessor drives the numerical controlled worktable and how to control step motor to accelerate and decelerate etc.At last, how to use CPLD to realize the data transmission through ISA bus between PC and microprocessor is investigated. A control board circuit to supply a hardware foundation for the total numerical control system is designed with anti-jamming measures improving the stability of the system.更多还原