An Intergrated System Of CAD/CAPP For Small Or Medium Manufacture Enterprise

In the past few years, CAD and CAPP have been realized in many Chinese enterprises, most of which were developed independently without the automatic transmission and exchange information between CAD and CAPP. Input of the part information in CAPP not only costs lots of time, but also goes wrong frequently, so the inadequate process is produced. Based on STEP(Standard for the Exchange of Product Model Data) standard, the system makes it possible to get the CAD/CAPP system share integrated information of machine parts, thus While finishing working graph design for a part, it produces the part processing procedures, shortens design and manufacture periods.The minor CAD system of the integration system developed by us is Parametric, comes true the full-scale dimension driving by the double link list. It is convenient to design the 2D working graph. Based on the international STEP standard, it has built the information model of machine part, including management information, shape feature information, precision information, technology information and so on. The system can generate the STEP file automatically through the feature recognition. The minor CAPP can automatically extract all of the geometric and technical information from STEP file. By means of interference expert system, it can generate the machinery manufacture process procedures of the part automatically. At the same time, according to the similitude both the structure and process, and to the structure feature matrix and match step by step, it can extract the similar case. After modifying the working graph and process procedure in the part case database, it can finish the new part design quickly. It is suitable for mechanical manufacture factory that is multiform and small-batch type to design the working graphs and process procedures.This essay introduces the design method and global structure of the system, explains its functions of major modules and design principles.