Building Of Open Three-axis CNC Milling Machine And Study On Function Modules

Open CNC compared to the traditional CNC system has many advantages, it can solve many problems in the field of NC. The PC-based open CNC system can be achieved most of the functionality of traditional numerical control system, It has become a major way of open CNC system implementation. The CNC system based on PC relying on the PC resources, so how to design a faster match NC code, how to improve the machining quality of the workpiece surface is the difficulties of open CNC system. This paper develops an open numerical experiment platform based on PC + motion control card, built hardware platforms, compiled the NC code, developed and designed the interface, and so on. The following are the main contents of this dissertation:Firstly, three major architecture of open CNC system is analyzed. The platform chose the NC board embedded in a PC as the type of research, the specific choice of "PC + motion control card" is chosen as the basic structure. Then the hardware platform is designed, the tasks of motion contro l is confirmed. Procurement is selected motion control card, motors, drives, drive and machine without the system. Through the selection of specific hardware and design of electrical schematic of the system, set up a three-axis milling machine and control cabinet.Secondly, compiling the decoding module which is very important to open CNC system, compiled into the language which motion control card can recognized. Selecting lexical analysis, parsing analysis, processing information table storage, and target code generation as the main structure of compilers. The common error types were in a different structure, so that the compiler has an error detection function, it can be given reported according to different error. At the same time, in the string matching, using the comparison of matching from right to left as the search keyword, not only can effectively identify the NC code, but the matching principle is simple, the compiling time is short er, the response speed is improved.Again, according to the modularity of open CNC system, man-machine interface module and simulation module had been designed. The interface had been achieved a good human-computer interaction, the CNC machine can complete the majority of operations; at the same time, the development of the machining path simulation module had been done; the tool path simulation had been achieved.Finally, through the experiments of face milling, end milling in mold and kanji track, so that it can verify that this platform can complete most of the three-axis milling capabilities.