【作者】 董景石；

【导师】 吴博达；

【作者基本信息】 吉林大学 ， 机械制造及其自动化， 2012， 博士

【摘要】 流体的高精度输送和分配是现代科技领域重要的试验手段，在生物医学、精细化工、医药研究等领域有着广泛应用，如实验室的药液配比系统、生物分析技术和高通量筛选技术等。现有的流体输送和分配系统通常体积较大、造价昂贵，使用上受到较多的限制，通常只能在实验室的环境当中使用。近年国内外开展了小型与微型流体输送和分配系统的研究。流体泵与流量传感器是流体输送和分配系统的主要部件，起着对流体的微量输送与精确检测并控制的重要作用，是系统中不可或缺的。在体积较大的传统型电磁泵的基础上，是无法制造出小型或微型流体输送和分配系统的，因此该系统的关键是如何设计制造小型化或微型化的流体泵。近年来，采用压电元件作为换能器的压电泵，成为微小型流体泵研究领域的热点。因为压电泵具有无电磁干扰、耗能低、结构紧凑、易于微小型化等特点，同时便于控制，可根据施加电压或频率精确控制压电泵的输出，所以压电泵比较适宜作为微型或小型流体输送和分配系统的流体泵。本文结合两个国家高技术研究发展项目“具有自检测功能的微型精密压电泵研究”（项目编号：2007AA04Z336）和“血糖检测与胰岛素注射微系统”（项目编号：2011AA040406）、国家自然科学基金重点项目“压电精密致动技术的基础研究”（项目编号：50735002）开展研究。以研发微型精密压电泵和用于胰岛素推注的压电微泵为目标，开展了关于精密压电泵的理论分析、有限元仿真、设计加工、试验测试等方面的研究。具体内容如下：1、压电驱动理论及压电振子振动分析压电振子是压电泵的换能器，其性能很大程度上决定了压电泵的输出能力。通过分析压电陶瓷材料的特性，选择与压电泵结构匹配的压电振子参数，对构建输出性能稳定的压电泵具有重要意义。在了解压电陶瓷基本性能参数的基础上，结合层合板理论，应用Hamilton原理，采用改变支撑边界的扭簧、弹簧和阻尼的方法模拟压电振子的真实工作边界条件，建立了压电振子在外力和外加电场作用下的振动方程，通过进一步的推导，得到了压电振子挠度的表达式，根据这个表达式分析了振子变形的影响因素，利用有限元软件对压电振子的变形进行了仿真。在不同的边界条件下，利用激光测微仪测试了双晶片压电振子的中心点的变形量，通过对比分析，测试结果能够验证有限元模型的正确性。2、压电泵用单向截止阀研究对于被动截止阀压电泵来说，其采用的单向截止阀的性能（工作中的阻尼，单向阀的刚度，开启压力，开启和关闭的滞后性）直接影响着压电泵的输出性能，比如自吸性、截止性、输出流量的精密性。对压电泵中单向截止阀的工作机理、工作方式及节流特性进行了分析。建立了单向截止阀的动力学模型，对动力学方程进行了仿真求解，验证了主要参数对单向截止阀运动规律的影响趋势。针对所采用的双腔体压电泵设计了悬臂梁式截止阀和盘式整体开启阀两种被动截止阀，分析了它们的过流特性，进行了相应的实验测试。应用有限元工程分析软件对悬臂梁式单向阀和盘式整体开启阀进行了设计和相关实验。3、双腔体精密压电泵的设计对现有的多振子压电泵设计方案进行分析，研究其工作特性，讨论了压电振子个数、腔体间的联接形式与输出能力的关系。针对精密输出的目的，给出了采用悬臂梁式单向截止阀和盘式整体开启阀构建双腔体精密压电泵的两种方案，设计并制作了不同结构的压电泵。分析了泵腔初始容积对压电泵工作的影响，提出了提高压电泵输出能力的方法。通过实验分析了悬臂梁式单向截止阀和盘式整体开启式单向截止阀对双腔体压电泵的性能影响，对压电泵的压力、流量－频率特性及精密输出特性进行了实验，验证了压电泵具有精密输出的能力。4、微型精密压电泵系统的应用研究提出了两种不同的实现流体精密输送的方案。方案一：后推式压电驱动型胰岛素泵的研究方案。提出把压电泵作为动力源，从注射器后面推动活塞注射药物的结构，通过试验研究表明：具有良好的截止性，可以避免药物的回流现象，压电泵不必与输药管一起频繁更换，可以重复使用，该系统的输出具有很好的稳定性。方案二：具有自检测功能的压电泵。提出将微型流量传感器和微型压电泵结合成为具有自检测功能的压电泵。研制了自检测功能压电泵及其实验装置，利用开环控制、最优线性二次型控制及模糊PID控制方法分别输送目标体积100μl，对输出重复性误差进行了分析，利用BP神经网络对压电泵的输出进行了辨识。5、自检测压电泵电控单元的研制根据压电泵的工作特点，针对不同应用场合，设计制作了压电泵专用电源控制器。进行了模糊自整定PID控制方法研究，根据输入、输出特性建立隶属函数和模糊控制规则，对比例因子进行自适应调整，以提高模糊控制精度，为掌握微流量控制规律提供了重要的设备和技术保障。本文的研究内容涉及压电学、机械学、流体力学、振动分析、控制学等多学科交叉的知识。论文的研究工作为精密压电泵的研究提供了新的思路，为小型或微型流体输送和分配系统提供了研究基础，对相近流体驱动装置的研制具有借鉴参考意义。更多还原

【Abstract】 The high precision delivery and distribution of reagent is a very important test means inthe mordern science and technology field. It is widly used in the fields of biomedicine, finechemical engineering and medical research, such as Liquid medicine proportion system,biological analysis technology and high throughput screening technology. The existingreagent delivery and distribution system usually features large volume and high cost. It isalso limited in the laboratory environment. In recent years, more and more small and microreagent delivery and distribution systems are developed at home and abroad.The pump and flow sensor is the main part of reagent delivery and distribution systemwhich is ndispensible part with the function of micro delivery, accurate detection and controlin this system. It can not be produced small and micro reagent delivery and distributionsystem based on a large volume fluid pump. The key point of this system is how to designand manufacture small and micro fluid pump.In recent years, adopting piezoelectric pump has been a focal point in the area of smalland micro fluid pump. The piezoelectric pump has the characteristics of no electromagneticinterference, low power consumption, compact structure, easy micro-miniaturization andgood controllability. The output of piezoelectric pump can be controlled by applied voltageor frequency precisely. So the piezoelectric pump is suitable for the adoption of fluid pumpin the small and micro delivery and distribution system of reagent.Funded by the two863programs of “Micro precision piezoelectric pump with thefunction of self-detection” and “Blood glucose test and insulin injection system”, Chinesenature science foundation key project of “Foundation research of piezoelectric precisionactuation technologies”, this dissertation aims to the development of micro precisionpiezoelectric pump and insulin injection micro piezoelectric pump. The theoretical analysis,FEM simulation, prototyping and experimental test are conducted for the precisionpiezoelectric pump. The specific contents are as follows.1. Piezoelectric actuation theory and vibration analysis of piezoelectric vibratorPiezoelectric vibrator is the transducer of piezoelectric pump. It’s performance determines the output abilities of piezoelectric pump. The matching piezoelectric vibrator forthe pump structure is chosen by analyzing the characteristics of piezoelectric material for theconstruction of piezoelectric pump with stable output performance.Combined with laminated plate theory and Hamilton principle, the vibration equationunder the external force and electric field is established and the deflection equation ofvibrator is derived based on comprehending performance parameters of piezoelectricceramic. The real working boundary conditions of vibrator are simulated by method ofchanging the torsional spring and damping. The influencing factors of vibrator deformationare analyzed by the equations. The deformation of piezoelectric vibrator is simulated by theFEM software. The central deformation of vibrator is tested by laser micrometer under thedifferent boundary conditions. The test results verify the correctness of FEM model throughthe comparative analysis.2. Study on the check valve of piezoelectric pumpFor passive valve piezoelectric pump, the performance of check valve, such as damping,stiffness of check valve, opening pressure and on/off hysteresis, influences the abilities ofself priming, cuting-off and accuration.The working principle, working mode and restriction characteristics of check valve inthe piezoelectric pump are analyzed.The dynamic model of check valve is established andthe main parameters for the influencing trend of check valve movement are verified bysolving and simulating the dynamic equations. The two type passive valves of cantilevercheck valve and disc holistic opening valve are designed for the twin vibrator pump. Theflow characteristic is analyzed and the corresponding performances are tested. The two typecheck valves are designed optimally by using the FEM software and the correspondingexperiments are conducted.3. The design theory of twin vibrator precision piezoelectric pumpThe existing design proposals of multi-vibrator piezoelectric pump are analyzed and theworking characteristics are studied. The relation of the vibrator number, the chamberconnection format and output abilities is discussed.The two type piezoelectric pumps with cantilever valve and disc holistic opening valveare designed according to the precise flow output. The prototypes of piezoelectric pumps aremanufactured. The influence of piezoelectric pump performance by the chamber initialvolume is analyzed and the method for improving the pumping abilities is presented. Theinfluence of pump performances by the two type check valves is tested. The precision output performance of piezoelectric pump is verified by the experiments of pressure, flow rate,frequency and precision4. The design of micro precision piezoelectric pump system and experimentalstudyThe two designs of fluid precision delivery are presented.Design1, back-push piezoelectric insulin pump. The piston of injector is pushed by thepower source of piezoelectric pump for the injection of fluid medicine. The results show thesystem has good cutting-off ability and can avoid the back flow of medicine. Thepiezoelectric pump is unnecessary to be replaced with the medicine pipe frequently. It is alsocan be re-used andthis system has a good continuity.Design2, the piezoelectric pump with the function of self detection. The piezoelectricpump with the function of self detection which is a combination of micro flow sensor andmicro pump structure is proposed. The pump system and experimental apparatus aredeveloped. The100μL fluid is delivered by the control methods of open loop, the optimallinear quadratic control and fuzzy PID. The output repeatability error is analyzed. The outputof piezoelectric pump system is identified by BP neural network.5. The development of control unit for the piezoelectric pump with self detectionThe power source controller for the piezoelectric pump is designed according to theoperating features of piezoelectric pump and different application occasions. The controlmethod of fuzzy self-tuning PID for the piezoelectric pump, control law of micro flow andthe abilities of precision delivery are studied. The membership function and fuzzy controllaw are established according to the input/output characteristics. The proportion factor isadjusted adaptively to improve the fuzzy control accuracy.The content of this dissertation relates to the piezoelectricity, mechanology, fluidmechanics, vibration analysis and contrology. The paper work provides a new idea for theresearch of precision piezoelectric pump and research foundation for the application of smalland micro reagent delivery and distribution system.It has the reference significance for the similar development of fluid delivery apparatus.更多还原