Research Of The Design And Process Technology Of The Variable Pitch Screw

As an important basic part in industrial production, screw is widely used in many industry fields, such as petroleum, metallurgy and chemistry industry. Specially in packaging field, screw must not only finish the arrangement process that make irregular bottle from disorderly movement to orderly movement in the process of transmission, but also make irregular bottle finish a series of actions, such as upright forward, horizontal turning and longitudinal lying. Therefore, the traditional design methods of screw are difficult to meet the transmission requirements of irregular bottle, and we must adopt a new design scheme.As the development of computer technique, simulating machining has become an important means of complex parts designing. Based on the analysis of container shape, on the basis of method for designing screw, which carries cylindrical bottles, a spiral equation of screw, which carries irregular bottles, has been deduced, and with the help of virtual machining, this paper has attempted a new screw design method, corrected the mathematical model of variable pitch screw, and developed a NC processing program of screw. Finally, with the method of actual measurement, the feasibility of this screw design method has been verified.Main jobs in this paper are as follows: The traditional design method of variable pitch screw has been studied, and the merits and demerits of traditional design method have been analyzed; By means of virtual machining, with the help of UG/Open Grip which is a secondary development tool provided by UG, by simulating the process of producing screw in the modeling environment of UG, the parametric design of variable pitch screw has been realized, and a new screw design method has been created; By creating tools, setting cutting parameters and post-processing in machining module of UG, numerical control codes for machining screw are obtained and virtual machining has been done; Based on the simulating of screw machining, by analyzing screws which emerge interference phenomenon, the existing mathematical model has been corrected, and a new mathematical model of variable pitch screw is obtained; According to the new mathematical model of variable pitch screw, an application program has been done with the help of Visual Basic, which can generate numerical control codes for machining variable pitch screw automatically; By measuring screw in the practical production and comparing measuring data with the result of virtual machining based on the new mathematical model of variable pitch screw, the new mathematical model has been verified.