Design,Analysis And Experiment Of High-performance Piezo Jet Dispenser System Based On Compliant Mechanism

With the application of electronic information technology in people’s daily life more and more widely,people’s demand for consumer electronic products such as smart phones,AR glasses,wearable devices,etc.is changing day by day.In order to meet the manufacturing needs of miniaturization and high density of these electronic products,precision dispensing technology is increasingly applied to the packaging manufacturing of such products.With the advantages of non-contact,high precision and high efficiency,piezo jet dispensers are gradually becoming the core equipment in electronic packaging manufacturing.In order to improve the efficiency and dispensing quality of piezo jet dispensers,this paper completes the design of a high-performance piezo jet dispenser system based on a compliant mechanism,and carries out structural design,static and dynamic modeling analysis,finite element simulation and experimental testing.Firstly,by analyzing the working efficiency and dispensing quality of piezo jet dispenser on the design requirements of piezoelectric actuator,this paper designs a hybrid displacement amplification mechanism based on the design principle of compliant mechanism,which combines a half-bridge amplification mechanism and a lever amplification mechanism,and has a large displacement amplification ratio to meet the working requirements of dispensing motion.The designed mechanism is analyzed with the simulation of fluid-solid coupling to prove the dispensing effect.Finally,the three-dimensional model a piezo jet dispenser system with high frequency response is designed.Secondly,in order to analyze the flexible deformation of the compliant displacement amplification mechanism,the static analysis of the amplification mechanism was carried out based on the compliant matrix method,during the analysis,it was found that the lever amplification mechanism has large lateral deformation,furthermore,based on the constrained beam theory,a more accurate theoretical modeling of the established static model was built to obtain the static performance of the equivalent stiffness and amplification ratio of the compliant displacement amplification mechanism,and the static performance was analyzed.Then finite element simulation analysis was performed to correlate the accuracy of the static model,the maximum structural design stress and the high transverse stiffness,and the structural parameters are optimally designed based on the finite element method.After that,the kinetic characteristics of the piezoelectric actuator and the dispense operation load in the piezo jet dispenser are investigated.Based on the kinematic analysis of the displacement amplification mechanism,the kinetic modeling of the designed mechanism is carried out based on the Lagrange method,and the hysteresis model of the piezoelectric ceramic,the liquid load generated by the solid-liquid coupling,the friction force during the movement of the firing pin and the impact force of the firing pin-nozzle impact are further established to form an overall dynamics model of the piezo jet dispenser system,and the advantages of the high frequency response characteristics of the designed mechanism are analyzed in conjunction with the solid-liquid coupling simulation.Finally,a compliant displacement amplification mechanism was fabricated to verify the static modeling work and the finite element simulation results,and the experimental test system of the piezo jet dispenser was built according to the dispensing experimental requirements.The accuracy of the static model was verified by comparing the experimental theoretical and simulation results,and the effects of dispensing frequency,glue supply pressure and duty cycle on the size of glue droplets were analyzed by dispensing experiments,and the dispensing consistency performance of the designed piezo jet dispenser system was tested.