Research On Yarn Tension Control System Of Automatic Winder

A constant yarn tension is a key factor for maintaining constant winding density in the process of automatic winding. The yarn tension is wavy, then the winding density of packages is asymmetric, which results in the inconstant yarn tension during winding in downstream process and the uneven dye. At present, the tension control technology of our nation is still low compared with the advanced technology.Based on the comprehensive yarn tension control technology, and by analyzing the generation of yarn tension, the factors which make the tension fluctuate, and the control method, a single-chip tension control system is brought up by this thesis. This control system consists of the data acquisition module, the tension control module, the tension adjustment and implementation module as well as the tension display and setting module. In the data acquisition module, several kinds of acquisition plans are proposed in this paper. Based on the system's actual situation, by analyzing and comparing this several kinds of acquisition plans, the resistance pressure sensor is finally chosen, and the measuring mechanism and the circuit are analyzed. There are many factors which affect the tension of yarn in the winding process, so it is difficult to build a mathematic model for the yarn tension. In view of this kind problem, the fuzzy control theory is introduced to the tension control module, and tension fuzzy controller is designed. And then, the system can be controlled effectively and owns good steady-state precisions. In the tension adjustment and implementation module, a new type of magnetic powder brake rotary tensioner is designed. Compared with the past tensioners, it reduces the friction to the yarn in high-speed operation and the hairiness. In addition, it is easy for achieving yarn tension control by changing the electrical parameters. In the tension display and setting module, a keyboard that has eight keys is designed, which is used for inputing the set value of tension. The actual yarn tension can be displayed on the liquid crystal display device and be analyzed by operators. Simultaneously the hardware circuit and the software of the control system are designed. By discussing the outside interference to the system in operation, the hardware and software measures are given.At last, based on the SIMULINK toolbox in MATLAB software, the system simulation is carried out. The simulation results show that the yarn tension can be controlled effectively and the system has a good anti-jamming ability.