Study On NC Automatic Programming System Based On The Environment Of Integration

NC machining plays an important role in advanced manufacturing technology .The efficiency and the quality of NC programming are the cruxes in NC machining. At present, auto-programming systems that applicable for medium or small plants of our country are very seldom. So that ,based on the integration environment , designing the auto-programming which combine with CAD, on the microcomputer, is the work having great potentialities and the tendency of NC programming development.Accounting for the NC machining situation of our country and NC programming developing tendency, this paper study on NC automatic programming system in the environment of integration for the NC lathe machining rotational parts. In the paper, the automatic programming is integrated with feature modeling and process planning. The structure of the system and the principle of its implementation are described.Since parts information can be described entirely by feature, feature plays an important role in the modeling. In the paper the feature is classified into internal and external feature according to rotational parts shape and manufacturing characteristics. At the same time the O-O(Object-Oriented) approach describing the feature class is provided.The analysis of process decision is provided, through which process information such as method ,order, remainder of manufacturing can be obtained. At the same time the system can provide technology interactive input and the practicality can be ensured.Some canned cycling functions of NC machine are used widely, which are described in the paper. The questions as how to plan the procedure of manufacturing based on canned cycling functions of NC machine and process information, how to recognize the cutting contour, how to construct the contour which can ensure the former cutting result and easy to go on with the later cutting are studied. The selection of the tool based on the algorithm of the collision, and the generation of the tool path are described. Finally the NC code are generated by the postprocess.