EP0568902A2 - Mikropumpe ohne Mikrokavitation - Google Patents
Mikropumpe ohne Mikrokavitation Download PDFInfo
- Publication number
- EP0568902A2 EP0568902A2 EP93106828A EP93106828A EP0568902A2 EP 0568902 A2 EP0568902 A2 EP 0568902A2 EP 93106828 A EP93106828 A EP 93106828A EP 93106828 A EP93106828 A EP 93106828A EP 0568902 A2 EP0568902 A2 EP 0568902A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- pump
- membrane
- micropump
- pump chamber
- descending
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 239000012528 membrane Substances 0.000 claims abstract description 31
- 230000001174 ascending effect Effects 0.000 claims abstract description 24
- 230000005284 excitation Effects 0.000 claims abstract description 19
- 230000007423 decrease Effects 0.000 claims abstract description 8
- 238000000034 method Methods 0.000 claims description 5
- 230000003247 decreasing effect Effects 0.000 claims description 2
- 239000011521 glass Substances 0.000 description 15
- 239000007788 liquid Substances 0.000 description 10
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 8
- 229910052710 silicon Inorganic materials 0.000 description 8
- 239000010703 silicon Substances 0.000 description 8
- 238000005452 bending Methods 0.000 description 5
- 230000008602 contraction Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005459 micromachining Methods 0.000 description 2
- 230000004913 activation Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 238000004581 coalescence Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000001259 photo etching Methods 0.000 description 1
- 238000000206 photolithography Methods 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B43/00—Machines, pumps, or pumping installations having flexible working members
- F04B43/02—Machines, pumps, or pumping installations having flexible working members having plate-like flexible members, e.g. diaphragms
- F04B43/04—Pumps having electric drive
- F04B43/043—Micropumps
- F04B43/046—Micropumps with piezoelectric drive
Definitions
- the descending ramp has a linear shape starting from the end of the holding phase during which the voltage is kept at maximum level, until the beginning of the next following ascending ramp.
- the descending ramp is linear and shorter than the time period between the end of the holding phase and the beginning of the next following ascending ramp.
- the descending ramp follows an exponential or otherwise non-linearly decaying curve.
- the present invention relates to a method of operating a micropump having a pump chamber which is closed by a pump membrane, which membrane is driven by a piezoelectric microactuator, whereby this method is characterized by the following steps:
- reference number 1 designates a micropump comprising a glass support body 4, a glass membrane 2 and sandwiched therebetween a silicon wafer 3, which has been machined by any appropriate technique such as photo lithography and etching in order to obtain a structure such as indicated in Fig. 1 in very simplified fashion.
- micropump of Fig. 1 The structure of the micropump of Fig. 1 is of course only an example, it being understood that the activation mode for a micropump according to the present invention is applicable to any other specifically structured micropump.
- micropump 1 comprises an inlet 6 and an outlet 5 for a liquid to be transported by the operation of the micropump, inlet 6 being provided with an inlet valve 7 and outlet 5 being provided with an outlet valve 8.
- Inlet and outlet valves 7 and 8 comprise membranes 11 and 12, which carry on their lower surface ring-shaped projections 13, 14 and 15, 16, which are located such as to surround the opening holes of inlet and outlet 6, 5 at the interface level between glass plate 4 and silicon wafer 3.
- a pump chamber 10 is provided whereas the thickness of land 17 of the silicon wafer determines the volume of pump chamber 10.
- Glass membrane 2 comprises a central portion 18 which carries a piezoelectric microactuator 9, which may be excited by an appropriate electric wave form in order to produce a periodically alternating contraction and expansion movement in a direction parallel to the plane of the membrane.
- the microactuator Since the microactuator is intimately attached to the membrane, the two elements together execute a bending movement according to the principle of a bimetallic strip, whereby the bending direction depends on the polarity of the applied voltage.
- microactuator 9 executes a contraction movement and, together with glass plate 2, bends in a direction such as to assume an upwards directed concave shape, and due to the maintenance of the side portions of glass plate 2 on the silicon wafer, membrane 18 of the glass plate bulges downwards such as to decrease the volume of the pump chamber 10.
- membrane 12 of outlet valve 8 bulges upwards in response to the pressure build-up within pump chamber 10 and annular projections 15, 16 are lifted from their seat on the upper surface of glass plate 4 in order to permit escape of the liquid contained within pump chamber 10 through outlet 5.
- microactuator 9 not only executes a bending movement but also a downwards movement due to the downwards bulging of center portion 18 of the glass membrane 2, whereas the degree of this downwards movement of microactuator 9 is a measure for the decrease of the volume within pump chamber 10.
- Fig. 3 illustrates an operation phase of micropump 1 corresponding to the end of a suction stroke whereby microactuator 9 has been excited previously in order to assume, together with the glass plate 2, a configuration in which both elements together form an upwards convex shape such that center portion 18 bulges upwards, due to the fact that glass membrane 2 is withheld at the side edges on silicon wafer 3.
- Pressure in chamber 21 which is located between the membrane of outlet valve 8 and glass membrane 2 is maintained at a level between minimum and maximum pressure of the liquid within pump chamber 10, in order to secure that outlet valve will securely open if pressure in pump chamber 10 essentially exceeds the pressure in chamber 21, and that the outlet valve is closed when the pressure in pump chamber 10 is essentially inferior to the pressure in chamber 21. Since a certain amount of pressure difference is required in order to overcome the pretension of the valve, this pressure difference has to be taken into account when regulating the pressure in chamber 21.
- the pressure in chamber 21 may be atmospheric pressure for applications where the liquid which enters into the micropump is maintained under atmospheric pressure and where, accordingly, the suction pressure of the micropump is slightly below and the thrust pressure of the micropump is slightly above atmospheric pressure, however, the pressure in chamber 21 can be adapted to any desired value corresponding to the needs and the application of the micropump.
- Fig. 4a illustrates a typical wave form for the excitation voltage of a prior art piezoelectric actuator for a micropump, whereby an ascending ramp 19 lasts approximately 1 ms, which is followed by a holding phase 22 at the end 24 of which begins the descending ramp 20 which lasts also approximately 1 ms. For the rest of the duration of a pump cycle which lasts between 100 and 1000 ms typically, the excitation voltage is kept at the lower level.
- the descending ramp according to Fig. 4b may last 10 to 100 ms depending on the entire duration of a pump cycle and on the duration of the holding phase 22.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Reciprocating Pumps (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB9209593A GB2266751A (en) | 1992-05-02 | 1992-05-02 | Piezoelectric micropump excitation voltage control. |
GB9209593 | 1992-05-02 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0568902A2 true EP0568902A2 (de) | 1993-11-10 |
EP0568902A3 EP0568902A3 (de) | 1994-03-02 |
Family
ID=10714963
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP93106828A Withdrawn EP0568902A2 (de) | 1992-05-02 | 1993-04-27 | Mikropumpe ohne Mikrokavitation |
Country Status (2)
Country | Link |
---|---|
EP (1) | EP0568902A2 (de) |
GB (1) | GB2266751A (de) |
Cited By (21)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE4405026A1 (de) * | 1994-02-17 | 1995-08-24 | Rossendorf Forschzent | Mikro-Fluidmanipulator |
DE19534378C1 (de) * | 1995-09-15 | 1997-01-02 | Inst Mikro Und Informationstec | Fluidpumpe |
EP0789146A1 (de) * | 1995-07-27 | 1997-08-13 | Seiko Epson Corporation | Mikroventil und methode zu seiner herstellung, mikropumpe die dies mikroventil benutzt und methode zu seiner herstellung, sowie vorrichtung die diese mikropumpe verwendet |
US5942443A (en) * | 1996-06-28 | 1999-08-24 | Caliper Technologies Corporation | High throughput screening assay systems in microscale fluidic devices |
US6074725A (en) * | 1997-12-10 | 2000-06-13 | Caliper Technologies Corp. | Fabrication of microfluidic circuits by printing techniques |
US6132685A (en) * | 1998-08-10 | 2000-10-17 | Caliper Technologies Corporation | High throughput microfluidic systems and methods |
US6267858B1 (en) | 1996-06-28 | 2001-07-31 | Caliper Technologies Corp. | High throughput screening assay systems in microscale fluidic devices |
WO2001090577A1 (fr) * | 2000-05-25 | 2001-11-29 | Westonbridge International Limited | Dispositif fluidique micro-usine et son procede de fabrication |
US6382254B1 (en) | 2000-12-12 | 2002-05-07 | Eastman Kodak Company | Microfluidic valve and method for controlling the flow of a liquid |
EP1313949A1 (de) * | 2000-08-31 | 2003-05-28 | Advanced Sensor Technologies, Inc. | Mikropumpe |
US6622746B2 (en) | 2001-12-12 | 2003-09-23 | Eastman Kodak Company | Microfluidic system for controlled fluid mixing and delivery |
DE10238564A1 (de) * | 2002-08-22 | 2004-03-11 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Pipetiereinrichtung und Verfahren zum Betreiben einer Pipetiereinrichtung |
EP1403518A2 (de) * | 2002-09-19 | 2004-03-31 | The Foundation for the Promotion of Industrial Science | Mikrofluidische Vorrichtung bestehend zumindest teilweise aus elastischem Material |
EP1489306A2 (de) * | 2003-06-17 | 2004-12-22 | Seiko Epson Corporation | Pumpe |
EP1959255A2 (de) | 1997-04-04 | 2008-08-20 | Caliper Life Sciences, Inc. | Biochemische Analysatoren mit geschlossenem Regelkreis |
US7749444B2 (en) | 2004-05-13 | 2010-07-06 | Konica Minolta Sensing, Inc. | Microfluidic device, method for testing reagent and system for testing reagent |
WO2011058140A3 (en) * | 2009-11-13 | 2011-12-01 | Commissariat à l'énergie atomique et aux énergies alternatives | Method for producing at least one deformable membrane micropump and deformable membrane micropump |
JP2017196614A (ja) * | 2010-05-21 | 2017-11-02 | ヒューレット−パッカード デベロップメント カンパニー エル.ピー.Hewlett‐Packard Development Company, L.P. | 流体ネットワークにおける流体流れの生成 |
US10272691B2 (en) | 2010-05-21 | 2019-04-30 | Hewlett-Packard Development Company, L.P. | Microfluidic systems and networks |
CN109882380A (zh) * | 2019-03-01 | 2019-06-14 | 浙江师范大学 | 一种双振子自激泵 |
US10415086B2 (en) | 2010-05-21 | 2019-09-17 | Hewlett-Packard Development Company, L.P. | Polymerase chain reaction systems |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4344743A (en) * | 1979-12-04 | 1982-08-17 | Bessman Samuel P | Piezoelectric driven diaphragm micro-pump |
US4519751A (en) * | 1982-12-16 | 1985-05-28 | The Abet Group | Piezoelectric pump with internal load sensor |
EP0393602A2 (de) * | 1989-04-17 | 1990-10-24 | Seiko Epson Corporation | Treiber für einen Tintenstrahldrucker |
EP0467656A2 (de) * | 1990-07-16 | 1992-01-22 | Tektronix, Inc. | Verfahren zum Betrieb eines auf Abruf arbeitenden Tintenstrahldruckkopfes |
GB2248891A (en) * | 1990-10-18 | 1992-04-22 | Westonbridge Int Ltd | Membrane micropump |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4449893A (en) * | 1982-05-04 | 1984-05-22 | The Abet Group | Apparatus and method for piezoelectric pumping |
-
1992
- 1992-05-02 GB GB9209593A patent/GB2266751A/en not_active Withdrawn
-
1993
- 1993-04-27 EP EP93106828A patent/EP0568902A2/de not_active Withdrawn
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4344743A (en) * | 1979-12-04 | 1982-08-17 | Bessman Samuel P | Piezoelectric driven diaphragm micro-pump |
US4519751A (en) * | 1982-12-16 | 1985-05-28 | The Abet Group | Piezoelectric pump with internal load sensor |
EP0393602A2 (de) * | 1989-04-17 | 1990-10-24 | Seiko Epson Corporation | Treiber für einen Tintenstrahldrucker |
EP0467656A2 (de) * | 1990-07-16 | 1992-01-22 | Tektronix, Inc. | Verfahren zum Betrieb eines auf Abruf arbeitenden Tintenstrahldruckkopfes |
GB2248891A (en) * | 1990-10-18 | 1992-04-22 | Westonbridge Int Ltd | Membrane micropump |
Cited By (45)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE4405026A1 (de) * | 1994-02-17 | 1995-08-24 | Rossendorf Forschzent | Mikro-Fluidmanipulator |
EP0789146A1 (de) * | 1995-07-27 | 1997-08-13 | Seiko Epson Corporation | Mikroventil und methode zu seiner herstellung, mikropumpe die dies mikroventil benutzt und methode zu seiner herstellung, sowie vorrichtung die diese mikropumpe verwendet |
EP0789146A4 (de) * | 1995-07-27 | 1998-10-28 | Seiko Epson Corp | Mikroventil und methode zu seiner herstellung, mikropumpe die dies mikroventil benutzt und methode zu seiner herstellung, sowie vorrichtung die diese mikropumpe verwendet |
DE19534378C1 (de) * | 1995-09-15 | 1997-01-02 | Inst Mikro Und Informationstec | Fluidpumpe |
US7091048B2 (en) | 1996-06-28 | 2006-08-15 | Parce J Wallace | High throughput screening assay systems in microscale fluidic devices |
US6306659B1 (en) | 1996-06-28 | 2001-10-23 | Caliper Technologies Corp. | High throughput screening assay systems in microscale fluidic devices |
US5942443A (en) * | 1996-06-28 | 1999-08-24 | Caliper Technologies Corporation | High throughput screening assay systems in microscale fluidic devices |
US6630353B1 (en) | 1996-06-28 | 2003-10-07 | Caliper Technologies Corp. | High throughput screening assay systems in microscale fluidic devices |
US6150180A (en) * | 1996-06-28 | 2000-11-21 | Caliper Technologies Corp. | High throughput screening assay systems in microscale fluidic devices |
US6267858B1 (en) | 1996-06-28 | 2001-07-31 | Caliper Technologies Corp. | High throughput screening assay systems in microscale fluidic devices |
US6274337B1 (en) | 1996-06-28 | 2001-08-14 | Caliper Technologies Corp. | High throughput screening assay systems in microscale fluidic devices |
US6046056A (en) * | 1996-06-28 | 2000-04-04 | Caliper Technologies Corporation | High throughput screening assay systems in microscale fluidic devices |
US6558944B1 (en) | 1996-06-28 | 2003-05-06 | Caliper Technologies Corp. | High throughput screening assay systems in microscale fluidic devices |
US6558960B1 (en) | 1996-06-28 | 2003-05-06 | Caliper Technologies Corp. | High throughput screening assay systems in microscale fluidic devices |
US6399389B1 (en) | 1996-06-28 | 2002-06-04 | Caliper Technologies Corp. | High throughput screening assay systems in microscale fluidic devices |
US6413782B1 (en) | 1996-06-28 | 2002-07-02 | Caliper Technologies Corp. | Methods of manufacturing high-throughput screening systems |
US6429025B1 (en) | 1996-06-28 | 2002-08-06 | Caliper Technologies Corp. | High-throughput screening assay systems in microscale fluidic devices |
US6479299B1 (en) | 1996-06-28 | 2002-11-12 | Caliper Technologies Corp. | Pre-disposed assay components in microfluidic devices and methods |
EP1959255A2 (de) | 1997-04-04 | 2008-08-20 | Caliper Life Sciences, Inc. | Biochemische Analysatoren mit geschlossenem Regelkreis |
US6509085B1 (en) * | 1997-12-10 | 2003-01-21 | Caliper Technologies Corp. | Fabrication of microfluidic circuits by printing techniques |
US6074725A (en) * | 1997-12-10 | 2000-06-13 | Caliper Technologies Corp. | Fabrication of microfluidic circuits by printing techniques |
US6495369B1 (en) | 1998-08-10 | 2002-12-17 | Caliper Technologies Corp. | High throughput microfluidic systems and methods |
US6132685A (en) * | 1998-08-10 | 2000-10-17 | Caliper Technologies Corporation | High throughput microfluidic systems and methods |
WO2001090577A1 (fr) * | 2000-05-25 | 2001-11-29 | Westonbridge International Limited | Dispositif fluidique micro-usine et son procede de fabrication |
US7311503B2 (en) | 2000-05-25 | 2007-12-25 | Debiotech S.A. | Micromachined fluidic device and method for making same |
US7005078B2 (en) | 2000-05-25 | 2006-02-28 | Debiotech Sa | Micromachined fluidic device and method for making same |
EP1313949A1 (de) * | 2000-08-31 | 2003-05-28 | Advanced Sensor Technologies, Inc. | Mikropumpe |
EP1313949A4 (de) * | 2000-08-31 | 2004-11-24 | Advanced Sensor Technologies I | Mikropumpe |
US6382254B1 (en) | 2000-12-12 | 2002-05-07 | Eastman Kodak Company | Microfluidic valve and method for controlling the flow of a liquid |
US6622746B2 (en) | 2001-12-12 | 2003-09-23 | Eastman Kodak Company | Microfluidic system for controlled fluid mixing and delivery |
DE10238564B4 (de) * | 2002-08-22 | 2005-05-04 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Pipettiereinrichtung |
DE10238564A1 (de) * | 2002-08-22 | 2004-03-11 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Pipetiereinrichtung und Verfahren zum Betreiben einer Pipetiereinrichtung |
EP1403518A3 (de) * | 2002-09-19 | 2004-04-28 | The Foundation for the Promotion of Industrial Science | Mikrofluidische Vorrichtung bestehend zumindest teilweise aus elastischem Material |
EP1403518A2 (de) * | 2002-09-19 | 2004-03-31 | The Foundation for the Promotion of Industrial Science | Mikrofluidische Vorrichtung bestehend zumindest teilweise aus elastischem Material |
EP1489306A2 (de) * | 2003-06-17 | 2004-12-22 | Seiko Epson Corporation | Pumpe |
EP1489306A3 (de) * | 2003-06-17 | 2005-11-16 | Seiko Epson Corporation | Pumpe |
US7749444B2 (en) | 2004-05-13 | 2010-07-06 | Konica Minolta Sensing, Inc. | Microfluidic device, method for testing reagent and system for testing reagent |
WO2011058140A3 (en) * | 2009-11-13 | 2011-12-01 | Commissariat à l'énergie atomique et aux énergies alternatives | Method for producing at least one deformable membrane micropump and deformable membrane micropump |
US10082135B2 (en) | 2009-11-13 | 2018-09-25 | Commissariat à l'énergie atomique et aux énergies alternatives | Method for producing at least one deformable membrane micropump and deformable membrane micropump |
JP2017196614A (ja) * | 2010-05-21 | 2017-11-02 | ヒューレット−パッカード デベロップメント カンパニー エル.ピー.Hewlett‐Packard Development Company, L.P. | 流体ネットワークにおける流体流れの生成 |
US10272691B2 (en) | 2010-05-21 | 2019-04-30 | Hewlett-Packard Development Company, L.P. | Microfluidic systems and networks |
US10415086B2 (en) | 2010-05-21 | 2019-09-17 | Hewlett-Packard Development Company, L.P. | Polymerase chain reaction systems |
US11260668B2 (en) | 2010-05-21 | 2022-03-01 | Hewlett-Packard Development Company, L.P. | Fluid ejection device including recirculation system |
CN109882380A (zh) * | 2019-03-01 | 2019-06-14 | 浙江师范大学 | 一种双振子自激泵 |
CN109882380B (zh) * | 2019-03-01 | 2020-04-21 | 浙江师范大学 | 一种双振子自激泵 |
Also Published As
Publication number | Publication date |
---|---|
GB2266751A (en) | 1993-11-10 |
GB9209593D0 (en) | 1992-06-17 |
EP0568902A3 (de) | 1994-03-02 |
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