A Study On The Piezoelectric Pump With Hydraulic Pressure Magnification Valve With Membrane And Homocentric Valve

In recent years, micro-flow systems and related technologies have become a very active research field. Piezoelectric pump due to have the merit of non- electromagnetic interference, compact structure, excellent response characterstic and can be controled accurately , especially received people's attention and already becomes hotspot in domestic and overseas research. Based on the analysis of the current status of piezoelectric pump research, this article propose the research program to active valve piezoelectric pump as follows:Through active controling the opening and closure of the enter valve and outlet valve of piezoelectric pump, explore the structure,material and response properties of one-way valve how to influence pump's performance,understood the basic issues and key technologies of the working performance of piezoelectric pump,building the foundtion for improvement and enhancement of the performance of piezoelectric pump, for development of high-energy output piezoelectric pump.Concrete research content as follows:1st, first carries on the theoretical analysis to vibration,bend and distortion of compound rounded piezoelectric vibrator , then conducts the more comprehensive experimental study to the piezoelectric vibrator, test its working ability in different operating conditions, and discovers the rule, determine the best work plan. May know through the experiment, piezoelectric vibrator distortion quantity is influenced by some factor as belows:voltage,waveform of the powersource, frequency and magnitude it's loaded.The magnitude of piezoelectric vibrator's distortion is increases along with the voltage increase,that is linear relationship;The waveform of power source also have a great influence to the distortion,under the same conditions as in the voltage andfrequency ,magnitude of piezoelectric vibrator's distortion is smallest when the supply waveform is the triangle wave ,next when it is sine wave,biggest when it is rectangular wave . Vibrator deformation magnitude is reduced when the load increased. Moreover, take the vibrator center as the zero point, its distortion quantity assume the parabola distribution along the radial direction, in the article also utilizes least squares method to fit this parabola concrete equation.2nd,With the full analysis of the current research status of piezoelectric pump, author proposed the concept of active cut-off valve ,and produced the heoretical model, elaborated it's working principle and the process.3rd, In view of the characteristic that distortion quantity of piezoelectric vibrator is very small , author designed the hydraulic pressure amplifier ,which can magnify distortion of the piezoelectric vibrator and used the membrane-type structure.This structure resolve the traditional hydraulic amplifier's problem effectively that leak-proof quality and high production cost.4th, A membrane-type hydraulic amplifier valve prototype has be made.Through the theoretical calculation and the experiment,the largest valve port size of active cut-off valve has be choosened.When the size between 0.2mm-0.4mm,the membrane-type hydraulic amplifier valve has better traffic and closure capacity.5th, Use piezoelectric vibrator as the derect driver,a kind of concentric active cut-off valve has be designed,in which piezoelectric vibrator used not only as a driver but also been involved in the sealing valve port. Because entry and exit valve is in the concentric position, therefore was called the concentric type active valve,whose merit lay in the non- enlargement organization, so the structure is simple, but considering from the craft angle,because of high processing precision request,traditional craft and techniques can hardly satisfy the demand.6th, Take the analysis of active cut-off valve as foundation, author has designed two kinds of piezoelectric pump separately use the hydraulic pressure amplificatory valve and concentric valve as active valve,and has analyzed theoretically respective principle of work and the work process,has calculated two the kind of pumps theroretical flow.7th,Two kind of different structure active valve piezoelectric pumpprototype has be made,it's performance trait has be studied experimental .As to membrane-typehydraulic pressure amplificatory valve piezoelectric pump, has tested the frequency -flux characteristic and the voltage - flux characteristic.The experiment indicated,when it's frequence is low,especially between 20 - 90HZ ,the membrane-typehydraulic pressure amplificatory valve piezoelectric pump has the better output current capacity level.Its current capacity increases along with the frequency increase, and presents good linear relation. This finding lay the foundation for the accurately control the pump flux.There is much disparity between the data obtained from experiment and the theoretically analytic result in the research of concentric piezoelectric pump.The reason is analysized and the main is that lower processing accuracy making prototype did not meet design requirements...