Analysis And Optimization Of Structural Parameters For Round Forming Shoulder Of Vertical Packing Machine

The vertical packaging machine can greatly reduce the dust leakage during the packaging process and can be used to package flake caustic soda,calcium chloride and other special chemical raw materials due to its no bag opening.However,it becomes a key technical issue that film of vertical packaging may fail in the process of surface forming,such as tearing and folding,and the structural parameters of lapel former is the main factor responsible for the failure above.In this thesis,the mechanical model and numerical simulation are studied,and the main contents and conclusions of this thesis are as follows:The system requirements and principle scheme of vertical packaging machine were described.The design constraints and external interface of the lapel shaper were analyzed.The working principle and key technology of the lapel shaper were studied.The core requirements of the lapel shaper were sorted out and its quantitative standards were given.The dynamic model of the lapel shaper was established.The difficulty of establishing the model was caused by complexity of geometric shape of the shaper.On the basis of the streamline model,the comprehensive surface segmentation was simplified into a set of several spatial surfaces.The equilibrium state dynamic equation of a single streamline was established.The single line model was sorted out and the mechanical model of the lapel shaper was built,and the mapping of structural parameters to film tension distribution was completed.The mechanical model was solved by numerical simulation,and three basic types of film tension distribution were summarized.The visualization of tension distribution was completed.The relationship between the tension curve and three-dimensional diagram of tension distribution,film failure mode and film forming quality was analyzed,and the solution results of mechanical model were corresponding to the requirements of forming machine.The interaction between streamlines,the unsteady state of acceleration and deceleration,and the influence of external environment factors on film tension were analyzed,and the optimization of mechanical model was completed.The influence trend and sensitivity of various structural parameters on the film tension distribution were analyzed.The mathematical expressions of the boundary conditions of cracks and folds and the optimization objective functions of fit degree and friction were derived.The optimization model of the structural parameters of the lapel shaper was established,and the numerical solution was obtained.The optimal structural parameters of the lapel shaper was obtained.A computer software simulation experiment based on Recur Dyn was designed.The similarities and differences between the model results and the simulation results were analyzed.The defects of the model were discussed and the direction of further optimization of the model was proposed.