Research on Interface Programming Method of CNC Milling Machine

After completing the 3D modeling, first set the blank size, then select the machining method, and set the machining parameters, and finally generate the machining tool path. The generated tool path is as shown. Since only the finishing of the part is done, only contour finishing is selected here. Comparing the two programming methods, the program written by the macro program is short and fine, and the program compiled by the automatic programming is much larger. The author uses the processing program generated by ProEngineer to adopt the contour finishing method. When the parameter is used, the minimum layer spacing and the maximum layer spacing setting value in the residual height are doubled, the machining precision and the machining allowance are doubled, and the generated program amount is also multiplied, and the user macro program is modified and processed. After the parameter, the amount of program remains unchanged. The user macro program has a clear structure, and the automatically programmed program cutting part of the statement reaches thousands of blocks, which is very difficult to understand.

If the contour curve of a machined part can be easily described by a mathematical expression, programming with a user macro is a relatively simple method. If you use automatic programming, you must use the computer and CAD / CAM software, first shape, then define the processing parameters, and finally generate the processing trajectory and processing code, the whole process is relatively troublesome. However, when the contour of a part is difficult to describe with mathematical equations, there is basically no way to program with a macro program, in which case only automatic programming is used.

The machining program obtained by the two methods has different control conveniences during the machining process of the machine tool. The user macro program can modify the parameters during the machining process, that is, the amount is found to be incorrect during processing, and can be modified immediately. If the program generated by the automatic programming finds that there is a problem in the operation, it must stop, re-use the CAD/CAM software to define the machining parameters, regenerate the program, and finally pass it to the CNC system, and the control time is very long.

The conclusion is that user macro programming and automatic programming have their own advantages and disadvantages. When the contour of a part can be described by a mathematical function, the application of user macro programming is an ideal choice. If the shape of the part is an irregular geometry, it is difficult to accurately describe it with a mathematical model, or describe it very well. Complex, only automatic programming methods can be used.

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