【文章內(nèi)容簡介】 C programmer and yet offers virtually unlimited freedom in the development of the program structure. Programming manually does have some disadvantages, but it teaches a tight discipline and organization in program development. It forces the programmer to understand programming techniques to the last detail. In fact, many useful skill learned in manual programming are directly applied to CAD/CAM programming. Programmer has to know what is happening at all times and why it is happening. Very important is the indepth understanding of every detail during the program development.Contrary to many beliefs, a thorough knowledge of manual programming methods is absolutely essential for efficient management of CAD/CAM programming.CAD/CAM AND CNCThe need for important improved efficiency and accuracy in CNC programming has been the major reason for development of a variety of methods that use a puter to prepare part programs. Computer assisted CNC programming has been around for many years. First, in the form of language based programming, such as APT? or Compact Ⅱ?. Since the late 1970’s, CAD/CAM has played a significant role by adding the visual aspect to the programming process. The acronym CAD/CAM means Computer Aided Design and Computer Aided Manufacturing. The first three letters (CAD) cover the area of engineering design and drafting. The second three letters (CAM), covers the area of puterize manufacturing, where CNC programming is only a small part. The whole subject of CAD/CAM covers much more than just design, drafting and programming. It is a part of modern technology also known as CIM – Computer Integrated Manufacturing.In the area of numerical control, puters have played a major role for a long time. Machine controls have bee more sophisticated, incorporating the latest techniques of data processing, storage, tool path graphics, machining cycles, etc. Programs can now be prepared with the use of inexpensive puters, using graphical interface. Cost is no longer an issue。 even small machine shops can afford a programming system in house. These systems are also popular because of their flexibility. A typical puterized programming system does not have to be dedicated only to programming – all related tasks, often done by the programmer, can be implemented on the same puter, for example, cutting tool inventory management, database of part programs, material information sheet, setup sheets and tooling sheets, etc. The same puter could also be used for uploading and downloading CNC programs.* IntegrationThe keyword in the acronym CIM is – integration. It means putting all the elements of manufacturing together and work with them as a single unit and more efficiently. The main idea behind a successful integration is to avoid duplication. One of the most important rules of using a CAD/CAM puter software is: Never Do Anything Twice!When a drawing is made in a CAD software (such as AutoCAD), then done again in a CAM software (such as MasterCAM), there is a duplication. Duplication breeds errors. In order to avoid duplication, most of the CAD system incorporate a transfer method of the design to the selected CAM system to be use for CNC programming. Typical transfers are achieved through special DXF or IGES files. The DXF stands for Data Exchange Files or Drawing Exchange Files, and the IGES abbreviation is a short form of Initial Graphics Exchange Specification files. Once the geometry is transferred form the CAD system to the CAM system, only the tool path related process is needed. Using a post processor (special kind of formatter), the puter software will prepare a part program, ready to be loaded directly to the