Templates Based Automatic Programming System For Electrode

For EDM, a tool electrode needs to be manufactured according to the shape of the geometry. For a complex workpiece, many electrodes are needed. Using general purpose CAD/CAM software to finish the NC programming work depends on the experience of programmers, and a lot of human-computer interaction have to be done. Owing to the large number of repetitive operations, the programming is not only inefficient, but also makes mistakes very often in choosing geometry and inputting parameters. Many electrodes examples and CNC milling process are studied in this paper. A templates based automatic programming system for electrode has been developed on the Unigraphics platform.According to CNC milling process and the programming characteristic of Unigraphics , in this system electrodes are classified, and the processing experiences of typical electrodes are incorporated into the templates. The templates contain tool library, processing methods, processing routine, common processing parameters and other useful information. In programming, the system invokes the templates, in accordance with user-selected electrode type and the size of electrode, to create processing parameters and process routes automatically.Because different parts of an electrode play different roles in EDM, electrodes are divided into three parts, i.e. discharge, extension and base. To differentiate them, three colors are used in design, so that the system is able to recognize different parts of electrode by colors. By means of classification and calculation of the identified geometries, the system can add geometry and change relative processing parameters automatically. According to the type of CNC machine tools, the system uses the equipped post-processor to generate NC program for the machines.The calculation efficiency of programming is considered in the paper, and a batch program is developed to calculation of tool path and NC programming, in which huge calculation is needed. Therefore, it is only needed for the programmer to configure the parameters for each electrode according to system requirements, and the huge amount of calculations will be done by computer in a batch mode and efficiency is improved drastically.