| Domestic and international markets competes drastically nowadays, the business enterprise wants to win the competetion in the end, have to carry on a new product development, CAD/CAM technique is the only way for the business enterprise to develop a new product.In the last few years, CAD part library's fast development brought business enterprise an efficiency.But also exist the problem of data explosion and data disorder, CAD software mostly and respectively for themselves, lack united standard, the parts library data can't share, can't carry out product class to use a design.Therefore it is urgent to establish parts library according to a united standard.The ISO13584 is an international standards of explanation on the computer,depicting and exchange of data of standard parts library.The parts libraty that is built in this standard, don't be under the controll of any CAD system, and can also be a kind of public data information and a data share to use, The standard structure of the ISO13584 is make up of concept layer, logic layer and physical layer three layer structure constitute.Concept layer the frame structure which defines a parts database and mechanism that allow a parts database to exchange and update.Logic layer use the EXPRESS language to describe database information model and source part that is needed .The physical layer regulate the way tocarry out the parts database model.According to the certain CAD terrace, the establishment of the spare parts database accoring to the ISO13584 standard, overcomes former weakness that independently develope a parts database leads to, carry out standard consistency that a parts database express and exchange information, thus can share resources.The CAD platform is an Unigraphics(brief name UG) in this thesis, is software system gathering CAD/CAM/CAE that the American EDS company releases.Aiming at the UG terrace I examin an establishment to match the possibility of the standard parts library of the ISO13584.Pipe connection is a part that is widely used in the machine design, and it's category is numerous, the series turns degree is high, it is necessiry to build up their 3D models in the parts library.The thread is one main characteristics of the pipe connection, the screw thread include three kinds of typical model forms :a common pipe thread,parallel screw thread, taper screw thread, each screw thread have an own ending of affair form. Constructing a pipe thread with the neutral language becomes the key to set up 3D entity for the pipe thread.Crest and tooth bottom of the parallel screw thread both have poured Cape, but the UG platform didn't supply a circle cape function, I adopt 2 kinds to carry out a method differently accoring to thread ending or not.This thesis made use of B curved face to carry out the ending of pipe thread for the first time, enriches the methods of stucturing complicated curved face. Because pipe connetion's thread amount may not only 1, and each thread type specification also don't be same, we can consider screw thread procedure as sub- procedure and adjust to use the screw thread sub- procedure in the pipe connection, it can reduce program task, and be advantageous to solve match phenomenon because of long main procedure.This thesis according to the demand of concrete topic item, on the foundation that the people of the past study a result, the entity model which studies familiar pipe connetions a body sets up a mold technique, write their neutral procedure according to ISO13584 standards .The thesis carry out 3D model of the fixer machine's rotor according to work experience before.
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