Introduction motivation the market for micropumps is steadily emerging especially in the field of medical products. The output voltage issued from the membrane transducer is monitored thanks to a digital oscilloscope. The displacement of the transducer was first measured statically and dynamically. The core component of the system is a piezoelectric diaphragm that can convert the reciprocating movement of a diaphragm actuated by a piezoelectric actuator into a pumping effect. Pump membrane the piezoelectric actuator model is imported into piezoelectric device module to analyze its behavior when a voltage is applied on the surface of the pzt5a disc. A novel piezoelectric pump called singlebimorph doubleacting checkvalve piezoelectric pump was proposed in this paper in order to improve the output performance of the singlebimorph singlechamber piezoelectric membrane pump. Intelligent control of piezoelectric micropump based on. Development and characterization a singleactivechamber. The effect of piezoelectric vibration on the flux at longer times 80 min was even more dramatic. Theory of piezoelectric materials and their applications in civil engineering by antoine ledoux submitted to the department of civil and environmental engineering on may, 2011 in partial fulfillment of the requirements for the degree of master of engineering in civil and environmental engineering 1 abstract.
It is bonded to the membrane with a conductive silver epoxy. Piezoelectric sensors are versatile tools for the measurement of various processes. This model considers pump and valve geometry, ambient pressures, excitation voltage shape sinusoidal, square. Micro piezoelectric pump is one core part of micro fluid system.
A piezoelectric driven variable volume having a chamber pump with a flexible tube and a noncompressible fluid therein. The piezoelectric effect is now used in many everyday products such as lighters, loud speakers and signal transducers. A radially polarized piezoelectric tube is simulated, with two sets of boundary conditions. Us6869275b2 piezoelectrically driven fluids pump and.
In this paper, a singleactivechamber piezoelectric membrane pump with multiple passive check valves is proposed. The piezoelectric actuator is a pzt5h piezodisk, the diaphragm is a borosilicate glass plate. It covers the piezoelectric properties of materials found inside the human body including blood vessels, skin, and bones as well as how the piezoelectricity innate in those materials aids in disease treatment. Design and simulation of a piezoelectric actuated valveless.
Piezo actuator technology has also gained acceptance. The pump uses a piezoelectric diaphragm transducer as the driving component, and two check valves located at the inlet and outlet to control the flow direction. A piezo ceramic mounted on a coated brass membrane is deformed when voltage is applied. A piezoelectric sensor is a device that uses the piezoelectric effect to measure changes in pressure, acceleration, temperature, strain, or force by converting them to an electrical charge. Jan, 2014 microdiaphragm pumps require compact drives which can provide a continuous flow and variable flow rates. Ultrasonic handpiece with cutting tips for a broad range of applications. Pdf intrinsic flow control of a piezo membrane pump. Piezoelectric micropump with nanoliter per minute flow for. The membrane transducer and a force sensor are rigidly fixed on the piezoelectric actuator.
Production and characterization of piezoelectric membranes. The first case illustrates the inverse piezoelectric effect, and the second case shows the direct piezoelectric effect. Thus, sensitivity of the sensors made with the piezoelectric polymers may be insufficient to detect detailed features of physiological signals. Wettability for the flow passage surface has a direct influence on the air bubbles flowing in the fluid. Modelling of micropumps using unimorph piezoelectric actuator. The metered amounts range from the milli, micro and nano to the picoliter range. Sensors free fulltext development and characterization a. Piezoelectric actuator vibration produces an oscillating flow and alters the chamber volume via curvature change of the membrane. Increasing the cross flow to 30 mlmin boosted this enhancement to 300%. What youre doing, when you press the switch, is squeezing a piezoelectric crystal, generating a voltage, and making a spark fly across a small gap. A classic piezoelectric membrane pump is comprised of a piezoelectric membrane, a pumping chamber connected to inlet and outlet valves, and pump body, as illustrated in figure1. The constituent parts of the newly designed piezoelectric pump have no difference with the singlebimorph single. Theory of piezoelectric materials and their applications in. Over the decades of research, the piezoelectric membrane pump referred to as piezoelectric pump has achieved significant improvement in terms of its performance and stability.
Under the condition of a fixed total number of passive check valves, by means of changing the inlet valves and outlet valves configuration, the pumping characteristics in terms of flow rate and backpressure are. The natural frequency of the pump is calculated as well as its performance as a function of. The effect of surface wettability on the performance of a. The fields of application for piezoelectric micropumps are in laboratory technology, medical technology, biotechnology. Swanson school of engineering in partial fulfillment. Due to the impedance matrices connecting the efforts and ows of the membrane, we have established the dynamic electric equivalent circuit of the transducer. Micro pump, micropump, curiejet piezoelectric micropump is a kind of micro diaphragmmembrane pump developed by microjet technology. The influence on the pumping performance is experimentally studied by altering the number of inlet valves and outlet valves, keeping the total number of check valves constant. Energy harvesting from vibration using a piezoelectric membrane. Bachelor of mechanical engineering, wuhan university of technology, 2012. The small volumes per pumping cycle mean high cycle rates of up to several 10 khz are. Diaphragms can be classified into external drive type and self drive type.
Ucl discovery is ucls open access repository, showcasing and providing access to ucl research outputs from all ucl disciplines. Piezoelectric materials for medical applications intechopen. Press a lighter switch and youll hear a clicking sound and see sparks appear. Us4344743a piezoelectric driven diaphragm micropump. A microdiaphragm pump comprises a valve unit and the pump diaphragm which, together with the piezoelectric actuator, form the pump drive. Piezoelectric diaphragm for vibration energy harvesting. Study on a piezoelectric micropump for the controlled drug. First, the piezoelectric actuator and membrane thicknesses were chosen by means of a stationary simulation, using the piezoelectric devices module we. A piezoelectric pump uses a pzt actuator to move a membrane in a chamber providing. Shapememory alloys magnetostrictive materials piezoelectric materials driving force thermal field magnetic field electric field materials tini, tipd tbfe, tbdyfe, smfe pzt, quartz advantages large forces high energy density high material strength high elasticity contactless control via magnetic field high frequencies. Piezoelectric effect and piezo technology piezoelectric materials convert electrical ener gy into mechanical energy and vice versa. In some applications however membrane type pumps suffer from flow rate dependency on backpressure for example. A ringshaped piezo centered around the aperture, on the membrane, flexes the membrane. In this model the piezoelectric action is considered as a periodic force acting on a pumping membrane.
While the last two models refer, respectively, to speci. In another embodiment, a fluid pump includes a chamber having one flexible membrane sidewall. Solenoid operated valves are associated with the inlet and outlet of the flexible tube. This disadvantage can be overcome by implementing flow control. Intelligent control of piezoelectric micropump based on mems. In this study, piezoelectric membrane sensor, consisting of a metal foil, a piezoelectric ceramic film and a top electrode, has been developed.
Figure 4 from intrinsic flow control of a piezo membrane pump. Development of piezoelectric diaphragm pump scientific. In order to prevent the backward flow of piezoelectric pumps, this paper presents a singleactivechamber piezoelectric membrane pump with multiple passive check valves. In fact, for macroscopic reciprocating pumps, where a. In this paper, we studied the effect of surface wettability on the bubble tolerance of a piezoelectric membrane pump, by applying the superhydrophilic or superhydrophobic surface to the key elements on the pump. Design and simulation of micro fluidic pump for drug delivery. This paper presents the design, fabrication, and performance evaluation of a biocompatible piezoelectric membrane actuator pma using polyvinylidene fluoridetrifluoroethylene pvdftrfe. Development and application of a diaphragm micro pump with piezoelectric device the actuator is moving downward for decreasing chamber volume shown in fig. Piezoelectric diaphragms are piezoelectric ceramic disks adhered to a metal plates of brass or nickelalloy. While the actuator is moving upward to increase chamber. The natural frequency of the pump is calculated as. By the resulting down stroke, the medium is being displaced out of the pump chamber below. The functional principle is based on a piezoelectric diaphragm in combination with passive check valves. Next, numerical solutions allow for great design flexibility and analysis which is not constrained by known analytical equations.
In piezoelectric pump actuation, a voltage is applied. A valveregulated inlet or outlet aperture through the membrane communicates with the pump chamber. It has a wide range of application and broad prospects in the industries such as biomedical science, fine chemicals, fuel feeding and household appliance. All the simulations were made using comsol multiphysics software. In order to avoid any interference from the noise in surrounding environment, the shaker is placed in an isolated bench. The piezoelectric actuator is excited at the working voltage of 50v 0 to peak and the excitation frequency much lesser than the natural frequency. In this paper some discrete parts of an electrostatic and flatwalled selfaligned valveless, micropump for drug delivery system is designed and simulated. While a few approaches with off the shelf micropumps and flow sensors have been demonstrated, up to now. In a rst study and in order to validate theoretical results, we. The piezoelectric element made from quartz, li tao 3, pzt or zno, has a thickness of 0. Nov 09, 2019 piezoelectricity is also used, much more crudely, in spark lighters for gas stoves and barbecues. It also covers piezoelectric materials and their use in medical implants.
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