a diaphragm micro-pump with piezoelectric device
DIAPHRAGM PUMP
专利名称：DIAPHRAGM PUMP 发明人：FOMIN, Vladimir Fjodorovich 申请号：RU2009000577 申请日：20091027 公开号：WO10/05084 8P 1 公开日：20100506
摘要：The diaphragm pump (3), for supplying salt water to a desalinator (1a body, the inner cavity of which is divided into three isolated sections by two symmetrically arranged flexible diaphragms. The central section (Б) is provided with a salt water inlet and an outlet for supplying the salt water to the desalinator (10). The side sections (A, B) contain a high viscosity liquid; furthermore, a multiplier (7) acting on the flexible diaphragm through the high-viscosity liquid, when the brine, flowing into the first side section from the desalinator (10), performs an action thereon, is accommodated in the first side section. A reciprocating plunger (4) is arranged in the second side section so that an action is produced on the flexible diaphragm through the high-viscosity liquid.
A Tactile Micro Gripper with Piezoelectric Actuator based on microsystem technology
A Tactile Micro Gripper with Piezoelectric ActuatorBased on Microsystem TechnologyFeng Qiao, Helmut WurmusIlmenau Technical University, Department of Microsystem Technology;P.O.Box 100565, D-98684 Ilmenau, GERMANY. Tel: 0049-3677-691295, Fax: -691296 Email: Feng.Qiao@mb.tu-ilmenau.deAbstractFor handling and assembling of small components one sort of micro gripper was developed. It has planar structure and flexure hinges, uses piezoelectric actuation and is fabricated with standard microsystem technology. Micro grippers made of both silicon and glass have been fabricated. Due to its etching angle, gripper made of silicon has no ideal hinge form, which leads to no good mechanical feature, while at glass almost all designs can be fabricated. HF signal was imposed at piezoactutor. A combination of resonant vibration of gripper structure and utilizing self-sensing effect of piezoelectric materials enables micro gripper tactile.Key words: micro gripper flexible hinge piezoelectric actuator tactileIntroductionAs a rapidly rising field, more and more micro components in different branches have been produced. Thus handling these micro components become necessary. Since the development of parallel-plate electrostatic micro gripper in the University of California [1], some micromachined grippers have been proposed in the literature. They use different actuation types: electrostatic, piezoelectric, suction, SMA and thermal bimorph effect [2,3]. Among them micro gripper with sensitivity of ETH Zürich [4] attracts attention.In Ilmenau Technical University micro grippers with planar structure made of silicon or photosensitive glass have been developed. It also uses planar piezoactuator (PZT), which simplifies the assembling work. In this paper one novel idea of combine resonant vibration of gripper structure and self-sensing effect of piezoelectric materials to enable gripper sensitive is presented.Design and FabricationFor the fabrication with microsystem technology, a planar structure gains advantage. This type of micro gripper uses piezoelectric actuation. Due to the limited produced displacement of piezoelectric actuator, a four-bar linkage mechanism is used to amplify the displacement ( Figure 1 ). Using compliant mechanism without screws brings much convenience. In this situation flexible hinges ( Figure 2 ) are used, which are also easy to fabricate using lithography and etching technology. The construction for flexure hinges and calculation of those dynamics will not be discussed in details here.Figure 1: Mechanism and sketch of micro gripperThe compliance of this type of flexure hinge is ( see Fig. 2 ) :2/52/129tb R M Z Z ⋅⋅⋅⋅⋅=πα (1)where ε is the Young’s modulus. And the stiffness of flexure hinge is the reciprocal of the compliance.For the fabrication both silicon and glass have been used as standard materials for microsystem technology. The fabrication will be done with standard process: with photo-lithographic method to get its outline, then the wafer will be etched.Due to its etching angle in fabrication, the hinge form of silicon-gripper can not be optimised as at glass wafer in Figure 2(Figure 3), which affects its mechanical features. Glass, in normal state, has an amorphous structure. It will be etched in all directions as an isotropic material. The UV-exposure changes the inner structure of a photosensitive glass. Through a final thermal treatment a real crystallisation will be generated. After these two processes a so-called anisotropic property will be got and glass can be etched as a real anisotropic material. The fabricating steps are listed in Fig.4. Compared with silicon,photosensitive glass has the advantage of being transparent, highaspect ratio and can generate any outline, which is impossible at silicon because of its etching angle. Thus grippers made of glass were chosen for further usage.characteristics of one microgripper with dimensions of 8.7mm ×13mm ×0.5mmWithout extending the gripper finger length, with simply changing construction parameter for flexure hinges different tip-displacement demands can be fulfilled . At another type with the same dimensions as the one shown in Fig.5, tip displacement with ±2×120µm at ±200V has been realised, and the maximal gripping force amounts 2mN. According to the theoretical calculation, the gripping force ought to be much higher. Perhaps the flexure hinges have consumed too much mechanical energy.Novel Idea Enabling Micro Gripper SensitiveIn technology it’s difficult to bring a sensing layer down to the glass service. A novel method to bring it sensitivity will be used.As shown in Figure 6, piezoelectric ceramic is covered with metallic layers on both sides, which serve as contact pad. At one side the metallic layer is cut into two parts. Onepart is used for actuating signal, the other for sensing signal. The sensor-part uses the inverse piezoelectric effect. At actuator-part DC-voltage overlapped with AC-signal is imposed. DC-voltage drives the gripper arm and AC-signal with small amplitude is used for sensing. Normally the sensing signal is also unclear opposite noise. Direct measuring brings no satisfying result. Thus HF-vibration helps to find one solution.For one free mechanical structure, for example a micro gripper without object, there are several resonant frequencies due to its elasticity. And at one micro gripper three resonant frequencies are found: 737 Hz,1605 Hz and 2340 Hz. And at resonant frequencies the phase shift between sensing and actuating signals is about π/2 (Figure 7). At resonant frequency the gripping process will be obvious. After gripping object both amplitude and phase of sensing signal will be greatly changed, which can be used as a criterion for detecting object.(a) (b)Figure 7 Dynamic features of free gripper: (a)Sensor signal spectrum; (b) Amplitude of sensing signal and phase shift between sensing and actuating signals around one resonant frequency (1605Hz): DC = 0V, AC-signal-amplitude = 8VAt one resonant frequency (1605Hz), the sensing signals of free gripper and gripper with object are shown in Figure 8. In Figure 8 (a), a little vague figure of gripper can be seen, because the free gripper vibrates at resonance. In Figure 8 (b), about π/2 phase shift between sensing and actuating signal can be observed. Correspondingly, the pictures in (c) (d) presentsensing signals after gripping object, and the sensing signalamplitude decreases greatly where the resonance disappeared.To investigate the gripping process, at beginning point one frequency at not exact resonance was chosen. Naturally when the DC-voltage is imposed on piezoactuator, the resonant frequencies will also depart from the originals because of the generated mechanical stress at flexure hinges. For gripping test one frequency of 750 Hz was chosen, while the original was 737Hz. And the AC-signal amplitude (p-p) was reduced to 4v. Inrunning course of gripping with object in Fig. 9, at point P1gripper tip just touched object, the resonant vibration was obstructed, which led to a sudden jump of phase shift up to 180degree. The gripper tips moved further towards inside till P2. AtP2 the sensing signal disappeared and there was only noise signal till P3. From P3 there appeared sensing signal again, with constant phase shift. We can conclude that under this situation there existed one firm gripping and the vibration of gripper tip was transferred through object. Also in running course of phaseshift in Fig. 9, the similar conclusion can be got from points A1, A2 and A3.Figure 8 (a) Figure 8 (c)Figure 8 (b) Figure 8 (d)Figure 8: (a) resonance of gripper tip; (b) actuating signal(above) and sensing signal under resonance;(c) one lens-carrier in gripper; (d) actuating signal (above) and sensing signal after gripping lens-carrier. Meaningfully the points P1, P2 and P3 coincide well with the points A1, A2 and A3, which means from both sensing amplitude and phase shift running courses information for gripping process can be got.Discussion and Further DevelopmentThe gripping tests were executed on different grippers. The resonant frequencies differ from each other a little. But with this method the gripping information could always be got. For further optimisation electronic circuits for automatically searching resonant frequencies within certain frequency field will be developed. We hope more information could be got through HF-vibrating.References:[1] Patrick B. Chu; Kristofer S.J. Pister: Analysis of Close-loop Control of Parallel-Plate Electrostatic MicroGrippers; IEEE Intl. Conf. On Robotics and Automation, San Diego, CA 1994[2] E. Westkämpfer, R.D. Schraft, C. Bark, etc.: Adhesive Gripper – a new approach to handling MEMS; ACTUATOR 96, 5th International Conference on New Actuators, Bremen[3] P. Lerch, C. K. Slimane, B. Romanowicz and P. Renaud: Modelization and characterization of asymmetrical thermal micro-actuators; J. Micromech. Microeng. 6 (1996), 134 – 137[4] G. Greitmann, R. A. Buser: A tactile microgripper for application in Microrobotics; SPIE Photonics East: Int. Symp. on Intelligent Systems and Advanced Manufacturing; Boston, Massachussettes, Nov. 1996[5] R. Kerschkerjan, F. Qiao, H. Wurmus : Piezoelectric X-Y-Micropositioner made of photosensitive glass to form one micro-handling unit. Actuator 2000, Bremen, June 2000。
MEMS-Micropumps A Review
Nam-Trung NguyenAssistant Professor,Mem.ASME Xiaoyang HuangAssociate ProfessorToh Kok ChuanAssociate Professor,Mem.ASME School of Mechanical and ProductionEngineering, Nanyang Technological University,Singapore639798MEMS-Micropumps:A ReviewMicrofluidics has emerged from the MEMS-technology as an important researchfield and a promising market.This paper gives an overview on one of the most important microf-luidic components:the micropump.In the last decade,various micropumps have been developed.There are only a few review papers on microfluidic devices and none of them were dedicated only to micropumps.This review paper outlines systematically the pump principles and their realization with parisons regarding pump size,flow rate,and backpressure will help readers to decide their proper design before starting a microfluidics project.Different pump principles are compared graphically and discussed in terms of their advantages and disadvantages for particular applications.͓DOI:10.1115/1.1459075͔1IntroductionMicroelectromechanical systems͑MEMS͒have enabled a wide range of sensors and actuators to be realized by allowing nonelec-trical devices onto microchips.In the early years of MEMS-development,fluidic components were among thefirst devices which were realized in microscale using silicon technology.The most common components were:flow sensors,microvalves and micropumps.With the growing importance of genomics,proteom-ics,and the discovery of new drugs,microfludic systems became hot research objects.Thefield of microfluidics expanded to the development of numerous micro devices:filters,mixers,reactors, separators.New effects such as electrokinetic effects,acoustic streaming,magnetohydrodynamic effect,electrochemical,and more,which previously were neglected in macroscopic applica-tions,now gained their importance in microscale.A recent report of System Planning Corporation͓1͔estimated a microfluidics market of3to 4.5billions US$and an annual growth rate for scales of25percent–35percent.The report con-sidered four types of microfluidic devices:fluid control devices, gas and liquid measurement devices,medical testing devices,and other devices.The reportfigured out that the most promising mi-crofluidics products are devices for DNA,protein analysis,and drug discovery.Since the establishment of the term‘‘microfludics,’’several ex-cellent review papers on microfluidic devices have been pub-lished.Gravesen et al.gave a general overview onfluidic prob-lems in micro scale͓2͔.Shoji and Esashi discussed microfluidics from the device point of view and considered micropumps,micro-valves andflow sensors͓3͔.Ho and Tai discussed the MEMS-applications forflow control in the macroscopic domain͓4͔.El-wenspoek et al.summarized their works on microfludics in͓5͔. Stemme discussed microfluidic devices under such categories: passive devices͑channel,valves,filters͒,flow sensors,and dia-phragm pumps͓6͔.Zengerle and Sandmaier concentrated on mi-crovalves,micropumps and their commercialization strategy͓7͔. Since thefield has been growing rapidly,it’s very difficult to cover all kinds of microfluidic devices in a single review.In con-trast to the previous reviews,this paper only deals with micro-pumps and discusses their design methodology as well as the de-velopment of pump designs in the published examples.The design methodology will cover two main aspects:the pump principles and their comparison.With this concept,the paper tries to give a general view on micropumps,and to help microfluidics designers making their development decision easily.Using the micromachining technology,a wide range of mi-crodevices has been realized.The most important micromachiningtechniques are bulk micromachining,surface micromachining,and LIGA technology.Bulk micromachining uses the starting sub-strate͑a silicon wafer͒as device material.Surface micromachin-ing is performed on the surface of a substrate,the substrate itselfusually doesn’t have a function in devices.LIGA-technology ͑German acronym for Lithographie Galvanoformung Abformung͒creates high aspect ratio structures using X-ray lithography andelectroplating.A short description of these technologies was givenin͓4͔.Many MEMS-devices combine two or more of the abovetechniques.A new trend,especially for microfluidic devices,usesplastic as device material.The common machining technologiesfor these devices are micro plastic molding or hot embossing.Combining with on-going investigation of polymer microelectron-ics,plastic microdevices promise a low-cost alternative to theirsilicon counterparts.2Pump PrinciplesIn contrast to another MEMS-devices,micropumps are one ofthe components with a largest variety of operating principles.Likeother MEMS-applications,thefirst approach made by researcherswas the micromachining realization of well-known principlesfrom the macroscale.Micropumps can be divided in two meancategories:mechanical pumps and nonmechanical pumps.Thefirst category usually utilizes moving parts such as checkvalves,oscillating membranes,or turbines for delivering a con-stantfluid volume in each pump cycle͓8͔.The second categoryadds momentum to thefluid for pumping effect by convertinganother energy form into the kinetic energy.While thefirst cat-egory was mostly used in macroscale pumps and micropumpswith relatively large size and largeflow rates,the second categorydiscovers its advantages in the microscale.Since the viscous forcein microchannels increases in the second order with the miniatur-ization,thefirst pump category cannot deliver enough power inorder to overcome its highfluidic impedance.Forflow rates larger than10ml/min,miniature pumps or mac-roscale pumps are the most common solution.The typical opera-tion range of positive displacement micropumps lies between10l/min to several ml/min.Forflow rates less than10l/min, alternative dynamic pumps are needed for accurate control of these smallfluid amounts.With theseflow rates,most of the pumps are working in the range of Reynolds number from1–100, and therefore in a laminar regime.All the pump principles,which were realized recently in mi-croscale,are discussed in details in the following subsections. 2.1Mechanical Pumps.All mechanical pumps require a mechanical actuator,which generally converts electric energy into mechanical work.The comparison of mechanical works generatedContributed by the Fluids Engineering Division for publication in the J OURNALOF F LUIDS E NGINEERING.Manuscript received by the Fluids Engineering DivisionAugust7,2000;revised manuscript received November7,2001.Associate Editor:Y.Matsumoto.384ÕVol.124,JUNE2002Copyright©2002by ASME Transactions of the ASMEby different pumps is discussed later in this paper.Shoji ͓3͔di-vided actuators into two mean categories:external actuators and integrated actuators.External actuators include:electromagnetic actuators with sole-noid plunger and external magnetic field,disk type or cantilever type piezoelectric actuators,stack type piezoelectric actuators,pneumatic actuators,and shape memory actuators.The biggest drawback of external actuators is their large size,which restricts the size of the whole micro-pumps.The advantage is the relatively large force and displacement generated by external actuators.Integrated actuators are micromachined with the pumps.Most common integrated actuators are electrostatic actuators,thermop-neumatic actuators,electromagnetic actuators,and thermome-chanic ͑bimetallic ͒actuators.Despite their fast response time and good reliability,electrostatic actuators cause small force and very small stroke.With special curved electrodes,electrostatic actua-tors are suitable for designing micropumps with very low power consumption.Thermopneumatic actuators generate large pressure and relatively large stroke.This actuator type was therefore often used for mechanical pumps.Thermopneumatic actuators and bi-metallic actuators require a large amount of thermal energy for their operation,and consequently,consume a lot of electric power.High temperature and complicated thermal management are fur-ther drawbacks of these actuator types.Electromagnetic actuators require an external magnetic field,which also restricts the pump size.Their large electric current causes thermal problems and high electric energy consumption.Check-Valve Pumps.Check-valve pump is the most common pump type in the macroscale.The first attempts in designing a micro pump were the realization of check-valve pumps.Figure 1illustrates the general principle of a check-valve pump.The pump consists of:•An actuator unit;a pump membrane that creates the stroke volume ⌬V ,•A pump chamber with the dead volume V 0,•Two check-valves,which start to be opened by the critical pressure difference ⌬p crit .Richter et al.͓16͔determined the operation conditions of a check-valve pump as:•Small compression ratio which is the ratio between the stroke volume and the dead volume ϭ⌬V /V 0,•High pump pressure p (͉p Ϫp out ͉Ͼp crit ,͉p Ϫp in ͉Ͼp crit ).Following design rules can be used in order to fulfill the above conditions:•Minimize the critical pressure ⌬p crit by using more flexural valve design or valve material with small Young’s modulus,•Maximize the stroke volume ⌬V by using actuators with large stroke or more flexible pump membrane,•Minimize the dead volume V 0by using thinner spacer or wafer,•Maximize the pump pressure p by using actuators with large forces.The terms for passive microvalves used in this paper were de-fined by Shoji in ͓3͔.One of the first micropumps made in silicon was presented by van Lintel ͓9͔.The pump had check-valves in form of a ring diaphragm,which was relatively stiff and need a large lateral area.That makes one valve consume a large silicon area,which has almost the same size of a pump chamber,Fig.2͑a ͒.The same valves were also used in the pumps reported in ͓10͔and ͓11͔,which had thermopneumatic actuators instead of piezodisks.The next improvement was the pump presented by Shoji ͓12͔,which had check-valves made of polysilicon by using surface micromachining.The valve is a disk supported by four thin polysilicon beams.This design allows small valves to be integrated under the pump chamber.Zengerle ͓13,14͔presented another small and more flexible design.The valve has a form of a cantilever,Fig.2͑f ͒.Koch et al.͓15͔and Wang et al.͓16͔pro-posed the same valve type in their micropumps.Another way to make check-valve flexible is using material with smaller Yong’s modulus.Table 1compares the common ma-terials used for check-valves in micro pumps.Polyimide,polyes-ter,and parilene is one order more flexible than silicon.Pumps presented by Shomburg et al.͓17,18͔used polyimide as material for the disk valve ͑Fig.2͑b ͒͒.The pump reported in ͓19͔and that presented by Kaemper et al.͓20͔had polyimide ring diaphragm valves ͑Fig.2͑c ͒͒.A similar design using polyester valve was reported by Boehm et al.͓21͔.In the pump presented by Meng et al.͓22͔,the disk valve was realized in parylene ͑Fig.2͑d ͒͒.The next optimization is to fabricate the pump membrane with flexural material like polyimide ͓19͔͑Fig.2͑c ͒͒or silicone ruber ͓22͔͑Fig.2͑d ͒͒.These membranes require small actuatingpres-Fig.1General structure of a micro check-valvepumpFig.2Check-valve micropumps:…a …piezoelectric actuator with ring mesa valves;…b …pneumatic actuator with polyimide disk valves;…c …pneumatic actuator with membrane valves;…d …pneumatic actuator with rubber membrane and parylene disk valves;…e …piezoelectric actuator with polysilicon disk valves;…f …electrostatic actuator with silicon cantilever valves;…g …pi-ezoelectric actuator silicon cantilever valves;…h ,i ,j …piezoelec-tric actuator with ring mesa valves.Journal of Fluids EngineeringJUNE 2002,Vol.124Õ385sure and have large deflection as well as large stroke volume.This type of membrane is suitable for pneumatic or thermopneumatic actuators.Using thinner spacer or thinner wafer for the pump chamber can minimize the dead volume.The pump presented by Zengerle ͓13͔͑Fig.2͑f ͒͒was in this way improved in the version presented by Linnemann et al.͓23͔.The middle wafer was polished and thined to 70micron.As a result,the compression ratio increased from 0.002to 0.085͓24͔.The improved pump design was able to pump gas and was self-priming.The design of van Lintel ͓9͔͑Fig.2͑a ͒͒was improved from the later version ͓25͔͑Fig.2͑b ͒͒and had a compression ratio of 1.15.This pump was self-priming and in-sensitive to ambient pressure because of the implementation of a special pump membrane limiter.Another good design,which minimizes the dead volume in the Linnemann’s pump,was com-bining the check-valve with the pump chamber realized by Gass et al.͓26,27͔͑Fig.2͑i ͒͒.Table 2lists the most important parameters of the above check-vale pumps and those reported in ͓28–33͔.The pump designs depicted in Fig.2also illustrate the ‘‘evolution’’in designing check-valve micropumps.The development shows clearly how the pump chamber becomes smaller,and how the check-valves and the pump membrane become more flexible.Most of the de-veloped micropumps tend to have a piezoelectric disk as actuator,which is reasonable for the performance and size needed for this pump type.Peristaltic Pumps.As opposed to check-valve pumps,peri-staltic pumps don’t require passive valves for the flow rectifica-tion.The pump principle is based on the peristaltic motion of the pump chambers,which squeezes the fluid into the desired direc-tion.Theoretically,peristaltic pumps need 3or more pump cham-bers with reciprocating membrane.Most of the realized pumps have 3chambers.Some pumps were designed with active valves,which in fact represent pump chambers,also belong to the cat-egory of peristaltic pumps.The optimization strategies are maxi-mizing the compression ratio and increasing the number of pump chambers ͑Table 3͒.Since a peristaltic pump doesn’t require high chamber pressure,the most important optimization factors are the large stroke vol-ume and the large compression ratio.The first peristaltic micro pump presented by Smits ͓34͔͑Fig.2͑a ͒͒had piezoelectric actua-tors and pump chambers etched in silicon.Shinohara et al.͓35͔presented a similar design with the same performance.Judy ͓36͔proposed a pump,which utilized surface microma-chining and electrostatic actuators ͑Fig.2͑b ͒͒.The pump chamber,and consequently the dead volume,can be kept very small.No results for maximum flow rate and backpressure were reported for this pump.The pump reported by Folta et al.͓37͔͑Fig.2͑c ͒͒used ther-mopneumatic actuators,the pump chamber height was 10micron.However,the heat loss caused by the good thermal conductivity of silicon minimized the thermopneumatic effect and increased the power consumption.Mizoguchi et al.͓38͔͑Fig.2͑d ͒͒also used thermopneumatic actuators for driving 4pump chambers,the pump had external laser light as heat source.Similar to the methods discussed in the previous section,Grosjean et ed silicone rubber in order to form the pump membrane ͓39͔͑Fig.2͑e ͒͒.With external pneu-matic sources,the pump could generate a flow rate up to 120l/min.In thermopneumatic operation,the pump only delivered few l/min like the similar designs in ͓37͔and ͓38͔.The pump presented by Cabuz et al.͓40͔increased the com-pression ratio to 10by using curved pump chambers and flexible plastic pump membrane for electrostatic actuation.The numerous pump chambers were designed by using a three-dimensional array structure ͑Fig.2͑f ͒͒.With these optimization measures,the pump was able to deliver 8ml/min with only 75V drive voltage and 4mW electrical power ͑Fig.3͒.Valveless Rectification Pumps.The structure of valveless rec-tification pumps is similar to those of check-valve pumps.The only difference is that instead of using check-valves the pumps use diffuser/nozzle or valvular conduit structures for flow rectifi-cation.Maximizing the stroke volume and minimizing the dead volume can optimize this pump type.Stemme ͓41͔presented the first pump with diffuser/nozzle structures.The pump was fabricated in brass using precision ma-chining ͑Fig.4͑a ͒͒.Further development of this pump leads to the flat design in silicon ͓42–44͔͑Fig.4͑b ͒͒.Using small opening angles ͑7–15deg ͒,the flow is pumped out of the diffuser structure ͑Fig.2͑a ͒͒.With deep reactive ion etching ͑DRIE ͒,small chamber height,and consequently small dead volume and large compres-sion ratio were achieved.The pump effect appears in the opposite direction if the opening angle is large.The pump presented by Gerlach had an opening of 70.5deg,which is determined by the ͗111͘surface freed with anisotropic wet etching ͓45–47͔͑Fig.4͑c ͒͒.This pump design was optimized in the work of Jeong and Yang ͓48͔.The stroke volume was increased by using the thermopneumatic actuator and corrugated pump membrane.Ullman gave in ͓49͔a theoretical analysis of diffuser/nozzle pumps.Forster et al.͓50,51͔applied the valvular conduits structure which was first invented by Tesla ͓52͔in micro scale.The inlet/outlet structures shown in Fig.5cause the rectification effect without check-valves.This pump type can be realized easily in silicon with DRIE-technology.Table 1Young’s modulus of differentmaterialsTable 2Typical parameters of check-valve micropumps …val-ues for water,except †18‡for air…Table 3Typical parameters of peristaltic micropumps …values for water…386ÕVol.124,JUNE 2002Transactions of the ASMEAnother approach of valve-less pumping was proposed by Stehr et al.͓53,54͔.The pump principles were called the elastic buffer mechanism ͑Fig.6͑a ͒͒and the variable gap mechanism ͑Fig.6͑b ͒͒.This pump type is able to pump liquids in two directions depending on its drive frequency.Nguyen et al.also demonstrated the pump effects in a similar structure ͓55͔͑Fig.6͑c ͒͒.Maysumoto et al.͓56͔presented another valveless concept by using the temperature dependency of water viscosity.The fluidic impedance at the outlet and the inlet are modulated by means of heat.The heating cycles were synchronized with the pump fre-quency.Table 4lists the most important parameters of the dis-cussed valveless rectification micro pumps.Rotary Pumps.Another mechanical pump type,which can be realized with micro machining technique,is the rotary pump.The rotary pump has a big advantage of pumping highly viscous fluids ͑Table 5͒.Ahn et al.͓57͔͑Fig.7͑a ͒͒presented a micropump with a mi-croturbine as rotor in an integrated electromagnetic motor.The pump simply adds momentum to the fluid by means of fast mov-ing blades.The rotor,stator,and coils are fabricated by electro-plating of iron-nickel alloy.The high aspect ratio structures were fabricated at a low cost by using conventional photolithography ofpolyimide.Fig.3Realization examples of peristaltic micropumps …not to scale …:…a …piezoelectric actuators with glass membrane;…b …electrostatic actuators with polysilicon membrane;…c …ther-mopneumatic actuators with silicon membrane;…d …thermop-neumatic actuators with silicon membrane and fiber guided la-ser as heat source;…e …thermopneumatic actuators with rubber membrane;…f …electrostatic actuators with curvedelectrodes.Fig.4Realization examples of valveless rectification micro pumps …not to scale …:…a …piezoelectric actuator with external diffuser Õnozzle elements;…b …piezoelectric actuator with planar integrated diffuser Õnozzle elements;…c …piezoelectric actuator with vertical diffuser Õnozzle elements;…d …thermoelectric actua-tors with corrugated membrane and vertical diffuser Õnozzle el-ements.Fig.5Valvular conduitpumpFig.6Other valveless pumpsTable 4Typical parameters of valveless rectification micro-pumpsTable 5Typical parameters of rotary pumps …typical size is the size of the turbine or the gear wheel…Journal of Fluids EngineeringJUNE 2002,Vol.124Õ387The micropump presented by Doepper et al.͓58͔͑Fig.7͑b ͒͒had two gear wheels made of iron-nickel alloy with LIGA-technique.An external motor drove the gear.The gears forced the fluid along by squeezing it to an outlet.Actuating by means of an external magnetic field is possible,but it is so far not reported.Mass production of this pump can be realized with plastic molding.Ultrasonic Pump.Ultrasonic principle is a gentle pump prin-ciple with no moving parts,heat and strong electric field involved.The pump effect is caused by the acoustic streaming,which is induced by a mechanical traveling wave ͑Fig.8͑a ͒͒.The mechani-cal wave can be a flexural plate wave ͑FPW ͓͒59,60͔or a surface acoustic wave ͓61,62͔.The mechanical waves are excited by in-terdigitated transducers ͑IDT,Fig.8͑b ͒͒placed on a thin mem-brane coated with piezoelectric film ͓59,60͔or on a piezoelectric bulk material ͓61,62͔.The pumps have a thin flow layer of about 20micron ͑for water ͒͑Fig.8͑a ͒͒,and are therefore also suitable for particle separation ing curved IDT,locally sample concentration can be achieved with this kind of pump.2.2Nonmechanical PumpsElectrohydrodynamic Pumps.Electrohydrodynamic ͑EHD ͒pumps are based on electrostatic forces acting on dielectric fluids.The force density F acting a dielectric fluid with free space-charge density q f in an inhomogeneous electric field E is given as ͓63͔:(1)where is the fluid permittivity,P is the polarization vector,and is the mass density.EHD pumps can be categorized into two main types:the EHD induction pump and the EHD injection pump.The EHD induction pump is based on the induced charge at the material interface.A traveling wave of electric field drags and pulls the induced charges along the wave direction ͑Fig.9͑a ͒͒.The first micromachined EHD induction pump was presented by Bart et al.͓63͔,similar designs were reported by Fuhr et al.͓64–67͔and Ahn et al.͓68͔.A fluid velocity of several hundred micron per second can be achieved with this pump type.For better pump-ing effect,a temperature gradient and consequently a conductivity gradient across the channel height was generated by an external heat source and heatsink ͑Peltier element ͓͒67͔.In the EHD injection pump,the Colomb force is responsible for moving ions injected from one or both electrodes by means of electrochemical reaction ͑Fig.9͑b ͒͒.Richter et al.demonstrated this pump principle with micromachined silicon electrodes ͓69,70͔.The pressure gradient bults up in the electric field causes the pump effect.Furuya et ed electrode grids,standing per-pendicular to device surface,in order to increase the pressure gradient ͓71͔.The pump can deliver 0.12ml/min with a drive voltage of 200V .Table 6lists the most important parameters of the EHD-pumps discussed above.Electrokinetic Pumps.In contrast to the EHD-pumps,electro-kinetic pumps utilize the electrical field for pumping conductive fluid.The electrokinetic phenomenon can be divided into electro-phoresis and electroosmosis.Electrophoresis is the effect,by which charged species in a fluid are moved by an electrical field relative to the fluid molecules.The velocity of the charged species is proportional to the field strength E :V ϭep E(2)where ep is the electrophoretic mobility of the species.Electro-phoresis is used for separation of molecules like DNA molecules.In contrast to electrophoresis,electroosmosis is the pumping effect of a fluid in a channel under the application of an electrical field.A surface charge exists on the channel wall.The surface charge comes either from the wall property or the adsorption of charges species in the fluid.In the presence of an electrolyte so-lution,the surface charge induces the formation of a double layer on the wall by attracting oppositely charged ions from the solu-tion.An external electrical field forces the double layer tomove.Fig.7RotarypumpsFig.8UltrasonicpumpsFig.9Principles of electrohydrodynamic pumpsTable 6Typical parameters of electrohydrodynamicmicropumps388ÕVol.124,JUNE 2002Transactions of the ASMEDue to the viscous force of the fluid,the whole fluid in the chan-nel moves with a flat velocity profile ͑plug flow ͒:V ϭeo E(3)where eo is the electroosmotic mobility of the fluid.Due to its nature,the electroosmosis effect was used for pumping fluid in small channels without applying a high external pressure.In micro analysis systems electroosmosis effect is used for delivering buffer solution,and in combination with the electrophoretic effect,for separating molecules.The most common application of elec-trokinetic pumps is the separation of large molecules like DNA or proteins.The device proposed by Harison et al.͓72,73͔could gen-erate a fluid velocity of 100m/s with a field strength of 150V/cm.Webster et al.͓74,75͔uses the gel electrophoresis for sepa-rating DNA-molecules in microchannel with relatively low field strength ͑5to 10V/cm ͒.Phase Transfer Pump.Beside the ultrasonic principle,electro-hydrodynamic principle and electrokinetic principle,phase trans-fer is another principle for pumping fluid in small channels,in order to overcome the high fluidic impedance caused by viscous forces.This principle uses the pressure gradient between the gas phase and liquid phase of the same fluid for pumping it.The realization in microscale is simpler than in other pump types.Takagi et al.͓76͔presented the first phase transfer pump ͑Fig.10͑a ͒͒.The alternate phase change is generated by an array of 10integrated heaters.The same pump principle was realized with stainless steel and 3heaters in ͓77͔.Jun and Kim ͓78,79͔fabri-cated a much smaller pump based on surface micromachining.The pump had 6integrated polysilicon heaters in a channel with 2micron height and 30micron width ͑Fig.10͑b ͒͒.The pump is capable to deliver a flow velocity of 160l/s or flow rates less than 1nanoliter per minute.Electro Wetting Pump.The electro-wetting pump was pro-posed by Matsumoto et al.͓80͔.The pump principle uses the de-pendence of the tension between solid/liquid interface on the charge of the surface.The principle can be used for direct pump-ing,but no example was reported.Lee and Kim ͓81͔reported a micro actuator based on electro-wetting of mercury drop,which can be used for driving a mechanical pump with check valves as proposed in ͓80͔.Electrochemical Pump.Electrochemical pumps use the pres-sure of gas bubbles generated by electrolysis water.Bi-directional pumping can be achieved by reserving the actuating current,which makes the hydrogen and oxygen bubbles reacting back towater ͓82͔.The pumped fluid volume can be measured by esti-mating the gas volume with the measurement of the conductivity between electrodes 2and 3͑Fig.11͒.Magnetohydrodynamic Pump.The pumping effect of a Mag-netohydrodynamic ͑MHD ͒pump is based on the Lorentz force acted on a conducting solution:F ϭI ϫBw ,(4)where I is the electric current across the pump channel,B the magnetic field strength and w the distance between the electrode ͑Fig.12͑a ͒͒.Lemoff et al.͓83,84͔realized this principle in silicon ͑Fig.12͑b ͒͒.The pump was able to generate a not-pulsatile flow like that of EHD-pumps and electrokinetic pumps.A maximum flow velocity of 1.5mm/s can be achieved ͑1M NaCl solution,6,6V ͒.MHD-pumps generate a parabolic velocity profile,similar to a pressure driven flow in channels.3Scaling Law for MicropumpsThe first question,which arises in dealing with micropumps,is what kind of pump can be actually called a micropump?Is that the size of the pump itself or is that the fluid amount the pump can handle?Since the above question is still unanswered,Fig.13il-lustrates the typical sizes versus the maximum flow rates of the published micropumps listed as references.The pumpchamberFig.10Phase transferpumpsFig.11ElectrochemicalpumpFig.12Magnetohydrodynamic pump:…a …schematic of con-cept,…b …design example,fluid flows out of pageplaneFig.13Flow rate versus typical size for mechanical pumps …the numbers indicate the corresponding references …Table 7Typical parameters of phase transfermicropumpsJournal of Fluids Engineering JUNE 2002,Vol.124Õ389。
爱普生的微电喷头结构
爱普生的微压电喷头结构
对于爱普生的微压电喷头技术和佳能的FINE打印头技术可谓无人不知无人不晓吧？一般维修的人都可能很少会去拆解打印头，更何况咱们普通用户更是对此一知半解了。
这次给大家带来的就是一位超强网友对打印头的深度拆解，绝对鲜活！
下面我们就跟随这位网友，以EPSON R290为例，带大家一起去看看打印头内部到底是什么样的内容！
首先要先把图中这3颗螺丝去掉
拿下后的样子
把保护电路板的胶垫去掉
圆圈表面处为墨水管通道
上面还残留有墨水的颜色
精密的导电陶瓷电压片
来个全景
喷头特写密密麻麻
看到一排排的小针了吗？
正面照
喷头电路板上还有小的控制IC
怎么样？很过瘾吧。
不知道大家了解了没，这就是著名的爱普生微压电喷头内部图，其实爱普生看似密密麻麻的喷嘴还不算多，佳能和惠普的产品要比爱普生的喷嘴还要多，只不过工作结构不一样，实际效果来说都是很出色的。
爱普生通过独有的微压电打印技术控制压电晶体形变，精确控制墨滴的大小，
确
保极出色的打印精度，最小墨滴可达
3.5
微微升
；在喷墨过程中，打印头不需
加热过程，
所以墨水的化学成分不会发生变化，
使得单个喷嘴在工作能保持高频
率的稳定性，
微压电喷头的喷射频率比热发泡喷头的喷射频率高，从而直接提升
整体打印速度。
A diaphragm pump
the outlet nozzle are positioned higher than the diaphragm in the case, and portions of the inlet path and the outlet path connecting to the inlet nozzle and the outlet nozzle are positioned higher than the diaphragm.
专利内容由知识产权出版社提供
专利名称：A diaphragm pump 发明人：Onishi, Hitoshi 申请号：EP 04 027523.2 申请日：2004 1119 公开号：EP 154 8284 A2 公开日：20050629 专利附图：
摘要：A compact pump includes a diaphragm vibrated by a piezoelectric element and a case. An inlet nozzle and an outlet nozzle are disposed on an outer surface of the case. An inlet path connects the inlet nozzle to an inlet and an outlet path connects the outlet nozzle to an outlet. At least one portion of the inlet nozzle and at least one portion of
申请人：Alps Electric Co., Ltd. 地址：1-7 Yukigaya-Otsuka-cho, Ota-ku Tokyo 145-8501 JP 国籍：JP 代理机构：Klunker . Schmitt-Nilson . Hirsch 更多信息请下载全文后查看
MICRO-MINIATURE PIEZOELECTRIC DIAPHRAGM PUMP FOR T
专利名称：MICRO-MINIATURE PIEZOELECTRICDIAPHRAGM PUMP FOR THE LOWPRESSURE PUMPING OF GASES发明人：YOUNG, Robert,FREIDHOFF, Carl, B.,POLLA, Dennis, L.,SCHILLER, Peter, J.申请号：EP95935010.9申请日：19950921公开号：EP0787261B1公开日：19981028专利内容由知识产权出版社提供摘要：A pump is provided for use in a solid state mass-spectrograph for analyzing a sample gas. The spectrograph is formed from a semiconductor substrate having a cavity with an inlet, gas ionizing section adjacent the inlet, a mass filter section adjacent the gas ionizing section and a detector section adjacent the mass filter section. The pump is connected to each of the sections of said cavity and evacuates the cavity and draws the sample gas into the cavity. The pump includes at least one piezoelectrically-actuated diaphragm. Upon piezoelectrical actuation, the diaphragm accomplishes a suction stroke which evacuates the cavity and draws the sample gas into the cavity. Preferably, the diaphragm is formed from a pair of electrodes sandwiching a piezoelectric layer.申请人：NORTHROP GRUMMAN CORP地址：US国籍：US代理机构：Harrison, Michael Charles更多信息请下载全文后查看。
Piezoelectric pump
Hale Waihona Puke 专利内容由知识产权出版社提供
专利名称：Piezoelectric pump 发明人：村中 司,宮崎 肇 申请号：JP特願昭63-293998 申请日：19881121 公开号：JP特許第3066027号(P3066027)B2 公开日：20000717
摘要：PURPOSE:To control the microflow of a fluid and prevent the fluid from flowing in and out of itself by constructing the title pump of a plate A stuck with more than at least three piezoelectric elements and a plate B comprising two through holes namely the inflow and discharge ports of a fluid. CONSTITUTION:Piezoelectric components 101104 for driving are bonded at an elastic plate 105. The inflow port 107 and the discharge port 108 of a plate 106 are placed respectively around the piezoelectric components 101 and 104. The plates 105 and 106 are bonded only by a bias part 205. Driving signals of the piezoelectric components 101-104 are sent from a driving circuit. Precise control of flow can be made due to the use of electrically acting piezoelectric components. In addition, as the inflow port is checked by the piezoelectric component, a fluid is prevented from flowing out.
Diaphragm pump
专利名称：Diaphragm pump 发明人：Erich Becker申请号：US05/650761申请日：19760120公开号：US04049366A公开日：19770920专利内容由知识产权出版社提供摘要：A diaphragm pump, especially a vacuum pump for gases, includes at least one diaphragm extending transversely through the pump housing and defining therewith a pumping chamber. Drive means connected to the diaphragm moves the latter between a suction stroke at which gas is sucked into the pumping chamber through an inlet and a compression stroke in which the gas is pushed out of the pumping chambers through an outlet. The diaphragm is clamped at its outer periphery to the pump housing and at its central portion to the drive means moving the diaphragm between the suction and compression strokes. In order to avoid vibrations of the diaphragm during its operation, the space within the pump housing on the side of the diaphragm facing away from the pumping chamber is maintained at a pressure smaller than the inlet pressure of the gas during the suction stroke whereby striking of the unclamped portion of the diaphragm against the surface of the pump housing defining the pumping chamber is avoided and the useful life of the diaphragm increased.申请人：BECKER; ERICH代理人：Michael J. Striker更多信息请下载全文后查看。
DIAPHRAGM FOR A DIAPHRAGM PUMP
专利名称：DIAPHRAGM FOR A DIAPHRAGM PUMP 发明人：RINNINGER, GERHARD申请号：EP97938821.2申请日：19970711公开号：EP0910745B1公开日：20021127专利内容由知识产权出版社提供摘要：The invention relates to a diaphragm for a diaphragm pump which has a diaphragm body (2) consisting of resilient material, comprising a substantially annular outer region of a relatively low thickness and an adjacent central region which becomes thicker radially towards the centre, and a solid moulded core (3) cured in the central region of the diaphragm body (2) and for connection to a pump drive part, wherein (a) the outer diameter (F) of the moulded core (2) is less than a third of the outer diameter (D) of the diaphragm body (1), and (b) the material thickness (L) of the diaphragm body (1) in the central region above the moulded core is between 5 % and 20 % of the outer diameter (D) of the diaphragm. Said diaphragm can be used to avoid, on both sides of the top dead centre region, undesirable deformation of the diaphragm (1) surface facing the pump chamber (5) during a tilt transmitted from the drive rods to the moulded core (3). Said diaphragm (1) can therefore be used to produce a diaphragm pump with a low clearance volume and a large compression ratio.申请人：ASF THOMAS INDUSTRIES GMBH,ASF THOMAS IND GMBH,ASF THOMAS INDUSTRIES GMBH地址：DE国籍：DE代理机构：Körber, Wolfhart, Dr. rer.nat.更多信息请下载全文后查看。
PIEZOELECTRIC MICRO-ACTUATOR FOR MAGNETIC TAPE REA
专利名称：PIEZOELECTRIC MICRO-ACTUATOR FORMAGNETIC TAPE READ/WRITE HEAD发明人：Ming-chih Weng,Turguy Goker,Ashok Nayak申请号：US11676873申请日：20070220公开号：US20080198506A1公开日：20080821专利内容由知识产权出版社提供专利附图：摘要：The claimed embodiments provide methods, apparatuses and systems directed to a servo-actuated positioner for a read/write head that uses a piezoelectric super fine actuator that moves the read/write head to maintain alignment with data tracks on amagnetic tape. The servo-actuated positioner, in one implementation, uses flexures to mechanically support the read/write head. Piezoelectric elements are attached to the flexures in strategic locations to effect movement of the read/write head when the elements are actuated. This configuration achieves a large actuator motion using small piezoelectric elements. Additionally, manufacturability is improved since the piezoelectric elements, which are typically brittle, are attached to the mechanically robust flexures.申请人：Ming-chih Weng,Turguy Goker,Ashok Nayak地址：Los Angeles CA US,Solana Beach CA US,Glendora GA US国籍：US,US,US更多信息请下载全文后查看。
DIAPHRAGM PUMP
专利名称：DIAPHRAGM PUMP 发明人：IMAGAWA ISAO申请号：JP2741484申请日：19840216公开号：JPS60173380A公开日：19850906专利内容由知识产权出版社提供摘要：PURPOSE:To improve the attachable or detachable properties of a valve body to or from a valve seat ever so better, by forming the valve body into being thinned in good measure, while making a top surface of the valve seat into a rising gradient toward a free end part at a tip of the valve body. CONSTITUTION:A tongue piece 22 extended to a sideward direction from a valve diaphragm being vibrated in reciprocating motion is installed. These are formed by eleastic materials including CR, etc. A valve body 23 for suction and another valve body for exhaust are parallelly installed in this tongue piece 22 and formed with some notches. The valve 23 for suction installs a step difference (t) from a top surface of the tongue piece 22 and formed into being thinned on a plane surface in good measure. Likewise, the valve body for exhaust installs the step difference (t) and formed into being thinned on a plane surface. A top surface 13a of a valve seat 13, where the suction valve body 23 is attached or detached at need, is made into an incline in a rising gradient toward a free end part at the tip from a base end part of the valve body 23. The exhaust valve body is also constituted in the same manner.申请人：KIYUUSHIYUU HITACHI MAKUSERU KK更多信息请下载全文后查看。
Diaphragm pump
专利名称：Diaphragm pump发明人：Fessler, Herman S.,Credle, William S., Jr.,Harvill, William A.申请号：EP81100270.8申请日：19810115公开号：EP0033096B1公开日：19841205专利内容由知识产权出版社提供摘要：A pneumatically powerable single action fluid pump has a housing, an improved diaphragm assembly dividing the housing into fluidly discrete propellant and pumping chambers, a fluid inlet and outlet in the pumping chamber, a fluid port to the propellant chamber and a spring motor biasing the diaphragm assembly in a direction away from the pumping chamber side of the housing; the diaphragm assembly includes a perforate rigid diaphragm plate, an elongate motor stem connected to the plate, a contiguous elastomeric diaphragm having an imperforate front layer covering a front side of the plate and stem, a rear layer on a rear side of the plate, pins in the plate perforations and between and adjoining the diaphragm layers, and a bellows section tothe outside of the plate. The spring motor biases the diaphragm to a position in close proximity to the fluid port of the propellant chamber in the absence of propellant therein against a plurality of spacer ribs. The spacer ribs permit an even and rapid distribution of propellant into the propellant chamber to drive the diaphragm assembly against the biasing action of the spring motor toward the pumping chamber.申请人：THE COCA-COLA COMPANY,THE CORNELIUS COMPANY地址：310 North Avenue, P.O.Box 1734 Atlanta, Georgia 30313 US,One Cornelius PlaceHighway 10 West Anoka Minnesota 55303 US 国籍：US,US代理机构：Abitz, Walter, Dr.-Ing.更多信息请下载全文后查看。
MICRO DIAPHRAGM GAS SAMPLING PUMPS 说明书
DATA SHEET E 004INNOVATIVE TECHNOLOGYWORLDWIDENEUBERGERINNOVATIVE TECHNOLOGYWORLDWIDE NMP 015 BNMP 09 M NMP 05 S ConceptThe Micro Diaphragm Gas SamplingPumps from KNF are based on a simple principal - an ela stic dia-phragm, fixed on its edge, moves up and down its central point by means of an eccentric. In this way the medium is transferred using automatic valves.The new range of KNF Micro Pumps is for the first time equipped with the patented stress-optimised structured diaphragm, resulting in a high pneumatic performance, a durable product and compact size.New, very efficient valves and sea-ling systems as well as the precise placement of the pump head are some of the other technical fea-tures we can offer.For pump drive we provide a selec-tion of dc motors with various levels of performance, durability and price.FeaturesUncontaminated flowNo contamination of the media due to oil-free operation Maintenance-freeCompact sizedue to structured diaphragm High pneumatic performance because of structured diaphragm High level of gas tightnessthanks to the closed diaphragm sur-face and special sealing system Low aerodynamic lossby means of a new valve system Long product lifethanks to structured diaphragm Ready for assemblyCan operate in any installed posi-tionFor the version with brushless motor the following also apply:•no sparks•safe and reliable constant use •particularly long durabilityAreas of useKNF Micro Diaphragm Pumps are used frequently in the fields of analysis and medicine.For instance as pumps for gas measurement, for example for sam-pling environmental conditions in the workplace, or for exhaust gas and smoke analysis or built into ma-chines for measuring blood pres-sure.As they are dc driven, the micro dia-phragm pumps are suited for use in portable and stand-alone equip-ment.Dimensions 3)(mm)NMP 05 MNMP 05 B(L i t r e a t S T P )Vacuum atm. Press.Pressure mbar abs.bar Vacuum atm. Press.Pressurembar abs.barVacuum atm. Press.PressureVacuum atm. Press.Pressurefor tube ID 3for tube ID 3Direction of rotationDirection of rotation Direction of rotationfor tube ID 3for max. M 2blackF l o w c a p a c i t y l /m i n (L i t r e a t S T P )a p a c i t y l /m i n a t S T P )a p a c i t y l /m i na t S T P )redMODEL CODES AND MATERIALSLitre at STPNMP 09 S 30.65±150 550NMP 09 S 50.75±150 550NMP 09 M 60.8±150500NMP 09 M2.50.85±150500Pump head Diaphragm Valves Ryton EPDM EPDMDimensions 3)(mm)NMP 09 MNMP 09 BF l o w c a p a c i t y l /m i n(L i t r e a t S T P )Vacuum atm. Press. Pressure …DRIVE OPTIONS“ (DC Motor Version) and …MODEL CODE EASY ORDERING“, see the next page.Vacuum atm. Press.PressureVacuum atm. Press.PressureDirection of rotationfor tube ID 3redblacka p a c i t y l /m i n t S T P )a p a c i t y l /m i nt S T P )mbar abs.bar mbar abs.barDirection of rotationVacuum atm. Press. PressureMODEL CODES AND MATERIALSPump head Diaphragm Valves Ryton 4)EPDM EPDMVacuum atm. Press.Pressurembar abs.bar ümbar abs.bar üVacuum atm. Press.PressureF l o w c a p a c i t y l /m i n (L i t r e a t S T P )F l o w c a p a c i t y l /m i n (L i t r e a t S T P )Direction of rotationfor tube ID 4for tube ID 4spade connector 2.8 x 0.4NMP 015 BNMP 015 MVacuum atm. Press.PressureVacuum atm. Press.Pressurea p a c i t y l /m i n t S T P )a p a c i t y l /m i n t S T P )Direction of rotationfor tube ID 4blackfor max. M 2for tube ID 4blackred Direction of rotationredTECHNICAL DETAILSMaximum permissible gas and ambient temperatur: between +5°C and +40°C.Motors with other voltages on request.4)Phillips Petroleum registered tradmark.In our extensive program you are sure to find the pump you need for your particu-lar application.KNF - the competent partner for vacuum and compressor technology. Especially for unusual problems. Call us and talk to our application engineers.Hints on function and installation:see back side.MICRO DIAPHRAGM GAS SAMPLIN G PUMPS WITH THE WORLD SMALLEST STRUCTURED DIAPHRAGM!MODEL CODE FOR EASY ORDERINGThe model code is identical to the order number. It is made up as follows:DRIVE OPTIONSOur Micro Diaphragm Pumps are availa-ble with a choice of four different drive motors.S - StandardThe pump is equipped with a standard dc motor.M - DC motor with iron-free rotorThe pump is equipped with a dc motor with an iron-free rotor. It provides a hig-her level of performance than the S versi-on and is ideal for more demanding ope-rations.L - DC motor with iron-free rotorThe pump is equipped with a dc motor which is based on the same technology as the M model but is even more robust and durable. This drive is ideal for higher operational. The model L pass the EU guideline 89/336 for EMC.B - brushless DC motorThe pump is equipped with a brushless electronically commutated dc motor (electronics integrated in motor). The motor runs vibration and spark free,almost silently, is very dynamic and extre-mely durable. This model can be used permanently at all pressure levels.KNF Neuberger GmbHDiaphragm Pumps +SystemsAlter Weg 3INNOVATIVE TECHNOLOGY WORLDWIDENEUBERGERINNOVATIVE TECHNOLOGY WORLDWIDE HINTS ON FUNCTION AND INSTALLATIONFUNCTION OFKNF MICRO DIAPHRAGM GAS SAMPLING PUMPSAn elastic diaphragm is moved up and down by an eccentric (see illustration).On the down-stroke it draws the air or gas being handled through the inlet valve.On the up-stroke the diaphragm forces the medium through the exhaust valve and out of the head. The compression chamber is hermetically separated from the drive mechanism by the diaphragm.The pumps transfer, evacuate and com-press completely oil-free. Diaphragm pumpHIN TS ON IN STALLATION AN D OPERATION•Range of use: Transfering air and gasesat temperatures between + 5 °C and + 40 °C.•Please check the compatibility of the materials of the pump head, diaphragm and valves with the medium.•The KNF product line contains pumps suitable for pumping aggressive gases and vapors - please contact us.•Permissible ambient temperature:beetween + 5 °C and + 40 °C.•The standard pumps are not suitable for use in areas where there is a risk of explosion. In these cases there are other products in the KNF program -please ask us for details.•The pumps are not designed to start against pressure or vacuum; when a pump is switched on the pressure in the suction and pressure lines must be atmospheric. Pumps that start against pressure or vacuum are available on request.•To prevent the maximum operating pressure being exceeded, restriction or regulation of the air flow should only be carried out in the suction line.•For the version with brushless motor the following also apply:Caution! Incorrect lead connection will damage motor electronics!•Components connected to the pumpmust be designed to withstand the pneumatic performance of the pump.•Fit the pump at the highest point in the system, so that condensate cannot collect in the head of the pump - that prolongs working-life.If you have any questions, please call our application engineers (see below for contact telephone number).。
Piezoelectric bimorph MEMS speakers
Piezoelectric bimorph MEMS speakersYiming Lang;Chengze Liu;Ahmed Fawzy;Chen Sun;Shaobo Gong;Menglun Zhang【期刊名称】《纳米技术与精密工程(英文)》【年(卷),期】2022(5)3【摘要】One of the key requirements for MEMS speakers is to increase the sound pressure level(SPL)while keeping the size as small as possible.In this paper we present a MEMS speaker based on piezoelectric bimorph cantilevers that produces a higher SPL than conventional unimorph cantilever speakers.The active diaphragm size is 1.4×1.4 mm^(2).The bimorph cantilevers are connected in parallel to make full use of the actuation voltage.At 1 kHz,the measured SPL reached 73 dB and the peak SPL reached 102 dB at the resonance frequency of 10 kHz in a 711 ear simulator under a driving voltage of 10 Vrms.The total harmonic distortion of the MEMS speaker was less than 3%in the range from 100 Hz to 20 kHz.Although the absolute SPL was not the highest,this work provides a better SPL for all piezoelectric MEMS speakers.【总页数】8页(P1-8)【作者】Yiming Lang;Chengze Liu;Ahmed Fawzy;Chen Sun;Shaobo Gong;Menglun Zhang【作者单位】State Key Laboratory of Precision Measuring Technology and Instruments University 300072;Nanotechnology Central Lab Research Institute(ERI) 12622【正文语种】中文【中图分类】TP2【相关文献】1.Modelling and analysis of circular bimorph piezoelectric actuator for deformable mirror2.Disk Bimorph-Type Piezoelectric EnergyHarvester3.Piezoelectric Vibration Harvesters Based on Vibrations of Cantilevered Bimorphs: A Review4.Analytical modeling of self-powered electromechanical piezoelectric bimorph beams with multidirectional excitation5.Applied theory of bending vibration of the piezoelectric and piezomagnetic bimorph因版权原因，仅展示原文概要，查看原文内容请购买。
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In general, avalveless pump cannot provide a high flow rate in a closed system with high flow resistance. Therefore, a new design of a one-side actuating micro-diaphragm pump (Ma et al. 2007) is developed to actuate the liquid by the vibration of a diaphragm with a thinner structure and a higher flow rate. 2 Development of a piezoelectric micro-diaphragm pump Generally, a diaphragm pump with passive check valves can overcome higher flow resistance and improve the performance. Ordinary micro-pumps cannot provide enough flow rates due to the limited actuating force by diaphragm’s displacement. Bohm et al. (1999) developed a plastic micro-pump with a valve which is capable of pumping both liquid and gas at pump rates 2 ml/min for water and up to 50 ml/min for air when the actuation frequencyis between 2 and 500 Hz. A commercial product
input voltage and frequency. The measured maximum flow rate of present design is 72 ml/min at zero total pump head in the range of operation frequency 70–180 Hz . Micro-pumps have been developed by using several actuation methods, such as electromagnetic (Bohm et al. 1999),piezoelectric (Stemme and Stemme 1993; Olsson et al.1996; Koch et al. 1998; Saggere et al. 2000; Suzuki and Yoneyama 2003; Yang et al. 2004; Li et al. 2005), shape memory alloy (Benard et al. 1998), electrostatic (Francais et al. 1997; Teymoori and Abbaspour-Sani 2005), and thermo-pneumatic (Takao et al. 2003) devices. Most of them have complex structures and high power consumption. On the contrary, piezoelectric actuation has advantages of a relatively simple structure and lowerpower consumption.
Micro-diaphragm pump can be classified as with or without valve. A valve-less pump consists of two fluid flow rectifying diffuser/nozzle elements which are connected to the inlet and outlet of a pump chamber with a flexiblediaphragm. Stemme and Stemme (1993) proposed the first prototype of valveless pump consisting of a circular cylin-drical volume where the top side had a thin brass diaphragmto which a piezoelectric disc was fixed. Its flow rate was 15.6 ml/min. Olsson et al. (1995, 1996, 2000) investigated the flow-directing properties of several diffuser elements with different lengths and opening angles for valveless micro-pumps. Numerical simulations were done by using the Computational Fluid Dynamics program ANSYS/ Flotran. Our study group also designed and simulated a valveless micro-pump which has a 0.5 mm thick chamber and a 20 degree open angle (Ma et al. 2006). The peak flow rate in the simulation was only 0.12 ml/min.
Of SDMP305D with central-actuating (Star Micronics Co. 2006), which is shown in Fig. 1, is a thin, compact, and lightweight micro-diaphragm pump. However, it is limited to the height, the control volume, and the mass flow rate due to its actuating displacement in z-direction by Piezoelectric effective. Its maximum flow rate is only 5 ml/min. 2.1 One-side actuating micro-diaphragm pump In Fig. 3, a new micro-diaphragm pump with piezoelectric effect has been designed to actuate the working fluid by the vibration of a diaphragm with one-side sector-shaped piezoelectric device.
Fig. 1 View of SDMP305D micro-amplitude of a piezoelectric device produces an oscillating flow and alters the chamber volume by the curvature change of a diaphragmWhile the actuator is moving downward to decrease chamber volume shown in Fig. 2a, the outflow will be in one direction with inlet valve closed and outlet valve open. While the actuator is moving upward to increase chamber volume shown in Fig. 2b, the inflow will be in the chamber with the inlet valve open and the outlet valve closed. The new design of the one-side actuating diaphragm pump with two check valves, which is shown in Fig. 3, allows the pump to be thinner and generates flow in one direction. In addition, the actuating force can be enforced by its harmonic resonance of the working fluid with the vibration of a rectangular piezoelectric device, PDMS diaphragm, and two check valves in the pump chamber.
List of symbols c Damping coefficient E Module of elasticity f Frequency F External force g Acceleration of gravity HL Head loss I Second moment of area of a rectangular section k Stiffness constant L Length of the valve M Bending moment m Mass P Pressure t Time v Velocity Greek symbols ζ Damping factor ρ Density ω Natural frequency