Kinematics Simulation And Dynamic Balancing Analysis For ZJ116 Cigarette Cutting System

ZJ116 cigarette-making machine at ultra-high speed is self-developed by China Tobacco Machinery Equipment Group.The research object of this thesis is the cigarette cutting system of the machine,which is mainly composed by ledger mechanismand cutter head mechanism.The geometric models of these mechanisms are established firstly,and then the virtual prototype model ofthe cigarette cutting system is built.The horizontal velocity ofthe blade is obtained by kinematic simulation,and the cutting error of the cigarette is sequentially calculated according to horizontal velocity deviation of the blade and the cigarette,which is a key evaluation index of cigarette cutting quality.Thereafter,the principle of dynamic balancing for the Ledger mechanism is investigated,and its dynamic balancing is analyzed and optimized by BP neural network and genetic algorithm.The main contents of this thesis are concluded as bellows:(1)The working principle of cigarette-cutting system was analyzed,and its geometric modelingand virtual prototype modeling were established.Based on the working principle of cigarette-cutting system,the modeling of Ledger mechanism and cutter head mechanism were established,the geometric modeling and virtual prototype modeling of the cigarette-cutting system were finished.To verify reliability of virtual prototype model and calculation results,taken inertia force of Ledger mechanism and horizontal velocity of the blade regard as evaluation index,the Ledger mechanism and cutter head mechanism were researched respectively by simulation and analytical calculation method.(2)The kinematics analysis forcutting process of cigarette-cutting system was conducted and thecutting error of cigarette was studied.The horizontal velocity of the ledger and the blade were obtained by simulating calculation of the kinematic model for cigarette-cutting system.Based on difference values of horizontal velocity between cigarette and blade,the process of cigarette cutting was analyzed and the cutting error was calculated.(3)The principle of dynamic balancing for the Ledger mechanism was analyzed.Dynamic balancing of the Ledger mechanism,takenmass-radius product of counterweight as evaluation index,was researched in terms of considered linkage and irrespective of linkage.The analysis results proved that linkage have important influence on dynamic balancing of the Ledger mechanism.Besides that,relationship between mass-radius product of two counterweights and length of cigarette was studied,relationship between equivalent mass of sliding block and length of cigarette was also studied.And the corresponding functions were obtained and its validity were verified.(4)Dynamic balancing for the Ledger based on BP neural network and genetic algorithm.While the angles of two counterweights in the ledger were taken as design variables and the root mean squares(RMS)of its inertia force and torque as optimal targets,the optimum function of its dynamic balance was constructed.The training sample of BP neural network was obtained by simulating calculation.Moreover,the numerical model for dynamic balance of the ledger was established based on BP neural network,and then a genetic algorithm(GA)was used to improve the prediction accuracy of BP neural network and to search the optimal value of the model.