Numerical control program generation

Abstract

Numerically controlled (NC) machine tools arise as a result of putting accurate digital measuring devices on the movements of machine tools and using electronically controlled motors to position them. Numbers coded into electronic signals can then position spindle and workpiece precisely without a human operator. If these signals are recorded on tape with other codes to activate the cutter motor and any auxiliary devices, clamping devices etc then the entire cycle of the machine can be controlled by a tape. Which codes achieve what is decided by the designer of the machine tool control circuits and can be different for different models of machine. The wide use of NC machine tools led to the development of languages for specifying the program of the cycle independently of the particular codes required for a particular machine. Using these languages, NC machine tools are programmed like a computer, the work being done by a part programmer who studies the drawings of the component and, using his knowledge of machining practice and the machine tool in particular, writes a program for the machine in the language. The program is compiled and the result is a cutter location file which is still independent of the particular codes of the machine tool. This file is then converted by a program written specifically for the machine, known as a post-processor, into the particular codes it requires.