Study On Numerical Control Last-Making Machine And Development Of Shoe Last CAM System

The last plays an important role in the shoe making industry. The design and manufacturing quality of last affects the quality of finished shoes directly. As the standard of living improved, people request better style and higher quality of shoes. On the other hand, compared with the developed countries, our nation's shoemaking industry is still backward. Only with advanced manufacture technology can we improve traditional shoemaking, and thus further to meet the need of consumers and get involved in the more and more intense international competition. So, the study on numerical control last-making machine with high reliability and low cost and the development of shoe last CAM system are very necessary. On the other hand, the research results can be used in other fields.Firstly, this paper introduces the domestic and international current situations of last designing and manufacturing, points out the distance between our country and other's in this field, and analyses the meaning of CAM technology in last making industry. The author analyses the principle and weakness of numerical control last-producing machine made by Chongqing University, on these basis, the author introduce the whole structure design of the numerical control last-producing machine. The last-making machine adopts inclined Lathe bed as its total arrangement scheme, which is not only good at getting rid of cut trifles, but also enhance the strong character and stability during manufacturing-process. Module design method is adopted during the lath bed design and alternating servo system is employed as the auto-control system of the last-making machine.Secondly, on the basis of introducing discrete modeling method, the author creates last's three-dimensional model, and build up algorithm model of tool position for numerical control last-making machine. Algorithm model applies sphere tool, which is most popular in processing curved surface nowadays. Moreover, the author puts forward "one-time approach method" as the theoretic foundation for the algorithm of tool position, so that this simplifies the calculation and increases greatly the efficiency of design and process. To verify the correctness of the algorithm for tool position, the author introduces digital simulation technology and simulates the calculated tool position using the technology. The result not only proves the algorithm for tool position, but also guarantees the accuracy and quality in last making, at the same time it analysesthe errors existing in the tool position calculating process.At last the author analyses the principle of digital control programs' manufacturing process, writes programs with Microsoft's visual C++ language, therefore controls the last-making machine to complete the last auto-process with software.