Research On The Full-cone Forming Shoulder And Analysis About Mechanical Properties

As one of the most important part on the vertical packaging machine, forming shoulder greatly affect forming quality, style and efficiency of the film bag. With the increasing demand for packaging products, diversification of shoulder and deeply study of its mechanical properties are urgently needed. Based on previous studies, this paper proposed a new kind of forming shoulder, and further studied the mechanical properties of the bending curve of the shoulder.First of all, this paper proposed the concept of the full-cone forming shoulder, the difference between it and traditional shoulder is changing rearview into conical surface too. In the paper, has established mathematical models when rearview and shoulder surface on one or two conical surfaces, derived relational curves and surface equations, finally verified them by establishing three-dimensional model under Pro/E. Also, based on the rearview and shoulder surface are on the same conical surface, deviated the collar bending curve and established three-dimensional model.Next, proposed the concept of mixed-back forming shoulder, it formed in the process when the traditional shoulder is changing into full-cone forming shoulder, derived relational curves and surface equations, established its 3-D model.Analyzed the position between two kind of shoulders and guide roll, especially the full-cone forming shoulder, to fix the position of guide better, studied changes in the distance between its rearview boundary curve and guide roll. Solution out the film boundary curve equation in all directions of this area. As several parameters are the same, contrasted changes of streamline included angle at collar bending curve, obtained conclusions that each shoulders has its advantages and disadvantages in this respect.At the end of the paper, created a new model about film go through a corner, provided a new clue to study stress condition when the film going through the collar bending curve of shoulder. Finally, had done a series of experiment, got some conclusions by analyzing experimental data, which supported some theories above and laid a foundation for the following experimental research.