Research On The Dynamics Of Rewinding And Unwinding Tension Control Strategy Of Coreless Rewinding Machine

High-speed automatic coreless rewinding machine is new equipment for production of coreless roll paper. The take-up mechanism and reliability of unwinding tension control system are directly related to the success of entire equipment design. So this paper researches the dynamics of paper rewinding process and the unwinding tension control strategy in two aspects of theory and experiment. It can provide a theoretical guidance for research and devel-opment of high-speed automatic coreless rewinding machine with independent property rights.Firstly, based on the model of small rigid bar interconnected by revolute joint with rotational spring-damper forces, dynamic simulations are performed by the software RecurDyn. The effect of Young's modulus, the thickness of paper and the shape of the curved orbit on the performance of coreless re-winding are discussed, which provide a reference for further research.Secondly, this paper builds a model for the paper rewinding tension con-trol system. The mathematical models of magnetic powder brake, swing roller, power amplifier and unwinding roller are established. Then a simulation mod-el is proposed. Based on the established model, four tension control strategies are simulated in the Simulink environment of MATLAB7.0, which are con-ventional PID control, fuzzy control, adjusting factor fuzzy control, adjusting factor fuzzy-PID control. The simulation results show that adjusting factor fuzzy-PID control can improve the adaptive capacity of tension control system. It can adapt the change of roll diameter in the unwinding process.Finally, the electrical control system is designed, which is based on PLC and servo motors. Experiments for dynamics of coreless rewinding and un-winding tension control are done on the machine. On one hand, this paper compares the effect of rewinding with or without baffles, on the other hand compares the effect in different shapes of curved orbit. Then a good shape of cured orbit is proposed. Meanwhile, conventional PID tension control experi-ments are done using the Siemens S7-200 PLC as tension controller,which verify the simulation results.The research on the coreless rewinding is still at the initial stage in China, which has not been reported yet. The study on the high-speed automatic core-less machine in this paper is of certain progressiveness in our country, which provides a reference for the design of similar automatic equipment.