Research And Development Of High Frequency Piezoelectric Injection Valve For Loom

In modern weaving industry,air-jet loom is widely used because of its high efficiency,low noise and clean energy.But the air-jet loom consumes a lot of energy,and the gas consumption accounts for 70% of the total energy consumption.This is determined by the working characteristics of weft insertion mechanism of air-jet loom,so the optimization research and design of high-performance weft insertion control valve has become the focus of textile professionals.Based on the piezoelectric ceramics,a high frequency injection valve for weft insertion of air-jet loom is designed by means of theoretical analysis,simulation and experiment.The injection valve is analyzed from the model,response characteristics and control algorithm.Firstly,according to the working characteristics of piezoelectric ceramics,the electromechanical coupling model of piezoelectric actuator is established by analyzing the energy equation.The variable parameter simulation of the actuator model is carried out from the time domain and frequency domain,and the dynamic performance index data is obtained,which ensures the effectiveness of the model.Then,the structure and working principle of the high frequency jet valve driven by piezoelectric ceramics are studied,and the finite element model and coupling model of the jet valve driving mechanism are established.The fourth-order mode of the flexure hinge lever is simulated,and the effects of damping ratio,equivalent stiffness of the actuator and equivalent mass of the valve core on the dynamic characteristics of the driving mechanism are analyzed.The results show that the step response time of the driving mechanism is 6 ms,the working bandwidth is stable,and the stable air flow can be output.Furthermore,the injection valve drive control system is built,and the system is designed from two aspects of hardware and software.Finally,aiming at the inherent hysteresis nonlinearity of piezoelectric ceramics,a self-tuning control method based on Fuzzy PID is designed.Through the analysis of the simulation platform,it is determined that the injection valve driving mechanism can open in 4.5 ms and close in 9.98 ms.Compared with the experimental data of weft insertion solenoid valve,the opening speed is increased by about 40%,and the closing speed is increased by about 30%.Considering the complexity of air consumption of air-jet looms,the air consumption can be reduced by about20% only from data observation.