Research Of The Piezoelectric Driven High Speed On-off Valve Based On Ellipse Amplification Mechanism

1,IntroduceThe high speed on-off valve has the high frequency sound, the high accuracy,the structure simple, the movement is quick, the reliable higher characteristic,specially with is accused as the electronic accounting machine relation bridgebetween the object, enables the people to be able to complete directly using theelectronic accounting machine to is accused the object control duty. Therefore, inrecent years more and more obtained people's value the high speed on-off valvetheory and the applied research, and has made the certain progress.This article introduced the domestic and foreign related high speed on-offvalves research present situation and the progress situation, has carried on thecomparison among the different type high speed on-off valve, and in the existinghigh speed switch valve foundation, design the Piezoelectric Driven High Speedon-off Valve Based On Ellipse Amplification Mechanism, A kind of hinge microdisplacement amplifier on the basis of the triangle amplification principle has beendeveloped for the first time on the basis of summarizing forefathers' study. Thepre-stage driver that make up of the displacement amplifier and the MPA (multilayerpiezoelectric actuators) is designed and produced. And the test of the piezoelectricon-off valve driven by pre-stage driver directly was carried.2,The basic principle of piezoelectric Actuation technologyBefore the system design of high-speed on-off valve, the paper was discussed deeplythe basic principles of piezoelectric ceramic and kinds of piezoelectric actuator forrationally designing the pre-stage driver of high speed on-off valve. It providedtheoretical dependence to the selection of piezoelectric actuator and the pre-stagedriver design of high-speed on-off valve.3,The characteristics analysis of MPAFor better understanding characteristics of piezoelectric actuator, based on theexisting experimentation data, measured the new data of the statics and dynamicsoutput characteristics of MPA, analyzed measure result and got the outputcharacteristics of the MPA displacement. According to the analyse, the MPA have theadvantages as following: the large displacement and high frequency of the actuator,high orientation resolving power, high efficient energy transition, steady outputdisplacement, small volume, low drive voltage, easy to use and low cost. Thecharacteristics of piezoelectric actuator's structure showed that it is adapted to thepre-stage drive component of piezoelectric High Speed on-off Valve.4,The analytic method and FE method of rhombus hinge micro displacementamplifierThe modeling study of the displacements amplifier, based on flexure hinges, wasprocessed by analytic method and FE method. The statics and dynamics analysis ofthe mechanism was carried on, and got the conclusion that the output displacementswere influenced by various structure parameters. The results were compared withanalytical solutions and showed that the output displacements of flexure hinge isinfluenced by centre thickness T, arc radius r, radianα , furthermore the outputdisplacements is not influenced by width . The resonance frequency and vibrationmodes of the mechanism were resulted by FE method. Finally, the system dynamicsparameter data from the analytic method and FE method was compared andanalyzed.5,Test and Research on the Piezoelectric Driven High Speed on-off ValveIn this thesis, an ellipse micro displacement amplifier based on the triangleamplification principle has been developed. The experiment and research ofpre-stage driver that was made up of amplifier mechanism and MPA was carried.The output characteristics of pre-stage driver of High Speed on-off Valve driven bypiezoelectric actuator were measured by using the precise measure and controlsystem. The statics and dynamics analysis of the mechanism was carried on. Theconclusion showed that the driver has the characteristics that large outputdisplacement and high response speed from the experimental research of pre-stagedriver that was made up of amplifier mechanism and MPA. So it can be shown thatFE analysis result has high accuracy. Flow characteristics,turn-on characteristics ,turnoff characteristics,response frequency were also measured in the paper.According to the analyze of the measure result, the Piezoelectric Driven High Speedon-off Valve almost achieves the ideal output characteristics.6,Conclusions1).The experiments proved that the FE method has good accuracy. The FEmethod is a effective method of statics and dynamics of structures.2).lacement amplifier based on the triangle amplification principle. To reducethe centre thickness t can enhance the output displacement;There is a maximum ofoutput displacement around 5°, and further reduction of angle α cannot increase theoutput displacement.3).he output displacement of pre-stage driver is 71μm, the amplification is6,and resonance frequency is 1450Hz. So the pre-stage has high speed characteristicsand certain drive capability.4).The experimental results of the Piezoelectric Driven High Speed on-offValve Based showed that the valve has flow characteristics. Through the dynamicanalysis we have measured the turning on time of this valve is 1.6ms, the turning offtime of this valve is 2.5ms.