The Study And Development Of Gears CAPP System

Computer Aided Process Planning(CAPP) means computer aided design and document formation for the mechanical parts manufacturing process.The application of this method in process design can make the problems such as heavy works for filling the forms,lower efficiency,lower reliability and the correct data information for share solved.CAPP is the key point of linking CAD/CAM and the integration of CAD/CAM and one of technical bases of CIMS.Therefore,the study and application of CAPP has very important significance.Hybrid system method was carried in the gear CAPP system based on Chunguang Mechanical Factory of Jiangsu University.And VB6.0,Access and AutoCAD were used in this system.The main research contents of this paper are as following:(1) The present situations of CAPP,development current of CAPP and the application of CAPP in mechnical industry were summarized.Considering the situation of Chunguang Mechanical Factory and process characters of gears,the function requirement of CAPP system was analyzed,the whole structure and the function modules of system were designed,and the supporting flat was decided.(2) The charchters and contents of design which combined structuring feature models technology with grop technology(GT) were studied deeply.Considering the situation of Chungnang Mechanical Factory and process characters of gears,the methods which included parts feature description and parts coding description were used.These methods can describe parts' information very well.(3) The data structure and the characters of process data in CAPP system were analyzed.The data models and the methods of structuring database were studied,and lots of data tables were constructured.(4) At first,the new gear coding system was used to describe gear information and constructure gear information model.Through selection of standard examples, calculation and comparison of similar coefficient(K,0≤K≤1) and transferring standard process document,the new gear technological process was formated.If K＜0.75,then the generative system(child system) was used.In this child system, through utilization of feature description,process reasoning strategy based on knowledge and the process decision automatically based on gear process stencil-plate, the new gear technological process was formated.Accordingly the practical requirement,intelligently and plasticity of CAPP system were enhanced.Moreover, because of man-machine interaction the practical requirement,reliability and plasticity of CAPP system were enhanced unlimitedly.The system can design practical processes,alleviate the burden of technologists, shorten producing cycle and enhance enterprise competitive power.