Design And Injection Characteristics Of A Single Piezoelectric Injection Dispensing Valve Based On ?-shaped Preloaded Spring

As the core technology of microelectronic packaging industry,dispensing technology has made outstanding contributions to the rapid development of the electronic industry.The rapid development of dispensing technology has greatly promoted the development and progress of electronic products,especially 3C products.Piezoelectric injection dispensing technology in the dispensing technology has become the most important choice of most electronic packaging at present,piezoelectric injection dispensing has a very high dispensing efficiency and excellent dispensing effect.In this paper,most of the existing piezoelectric injection type dispensing valve relies on the traditional spring to preload the piezoelectric ceramic.Due to the high assembly precision requirements of the piezoelectric valve,it has a greater dependence on the spring's dimension accuracy,which affects the assembly efficiency of the piezoelectric valve to some extent.In addition,because the traditional spring occupies a larger space,it is bound to hinder the miniaturization of the point valve development.Based on the accumulated dynamic theory of fluid injection and the design and development experience of the dispensing valve,aiming at the above problems,the paper aims to design a more compact and can be applied to a wider viscosity range of multi-functional high-precision single piezoelectric driven dispensing valve,to promote the renewal and development of the piezoelectric injection dispensing technology.In this regard,this is carride out in this paper mainly the following aspects of research:(1)based on the theory of piezoelectric ceramic,the working principle of piezoelectric dispensing valve system level modeling analysis,respectively for piezoelectric glue dispensing valve drive control valve system power link,link of piezoelectric ceramic,displacement and displacement amplification mechanism linkflow transformation part four analyses the evaluation of modeling and feature.(2)the single piezoelectric ceramic drive scheme is adopted to design a space-saving and efficient integrated wire-cut type return spring,and the stiffness design requirements of the return spring are determined.Through the comparison and analysis of the displacement amplification principle of different types of amplification,it is determined that the displacement amplification mechanism is designed based on the lever displacement amplification principle.ANSYS workbench was used to analyze the stress and output displacement performance of the drive structure,and the test bed was built to test the static and dynamic performance of the drive structure,and the output displacement was almost the same as that of the simulation structure.The heating characteristics of the piezoelectric ceramics were tested,the heating law of the piezoelectric ceramics was summarized,and the heat insulation performance of the dispensing body was tested.(3)the structure of the firing needle and nozzle is determined.In order to improve the neutralization of the firing needle,a guiding device of the firing needle is proposed.Using Fluent fluid simulation software on the firing pin guide device model for the simulation analysis of fluid jet behavior separately inspected the firing pin internal cone Angle,firing pin head diameter,nozzle hole diameter,nozzle hole length,firing pin movement form for glue,glue solution viscosity,pressure,firing pin movement speed the influence law of the performance of dispensing valve injection,to determine the effectiveness of the proposed structure.(4)complete the dispensing valve assembly and dispensing injection test system,chose to fusing agent,UV glue,adhesive glue,conductive silver pulp and other four different viscosity range of industrial adhesive solution is commonly used for piezoelectric valve injection experiment,based on the access jet under different injection process parameters of high-speed photograph,system analysis and contrast the change rule of different viscosity colloidal injection form,based on the jet colloid quality measurement,the performance of the piezoelectric dispensing valve injection consistency and accuracy is evaluated and analyzed.