JP2006161779A - Micro pump and manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a micro pump delivering a minute quantity of liquid at high pressure with high accuracy. <P>SOLUTION: The micro pump 50 comprises a port substrate 13 provided with two liquid entrance and exit flow passages 19 opening to a minute flow passage 16, a valve substrate provided with two valve diaphragm 11A and pump diaphragm 11B, a valve piezoelectric element 15A for displacing the valve diaphragms 11A and a valve piezoelectric element 15B for displacing the pump diaphragms 11B. Thick-wall portions 18A, 18B are formed in a central part of the valve diaphragm 11A. The valve piezoelectric elements 15A, 15B are composed of laminated piezoelectric elements and are installed in drive section installing holes 12A, 12B of the valve substrate 13. One sides of the piezoelectric elements 15A, 15B are fixed to the thick-wall portions 18A, 18B and the other sides are fixed to positioning pins 20A, 20B. The positioning pins 20A, 20B are fitted in and fixed to the drive section installing holes 12A, 12B. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a micropump and a method for manufacturing the same, and in particular, a micropump capable of feeding a small amount of liquid to a chemical synthesis device, a chemical analysis device, a medical analysis device, or the like using a microchip having a microchannel, and It is suitable for the manufacturing method.

  As a conventional micropump applied in the fields of medicine, chemical synthesis and analysis, for example, there is one disclosed in JP-A-11-257232 (Patent Document 1). This micro pump is bonded to a valve substrate (glass substrate), forms a micro flow channel (flow channel part) between the micro pump and the port substrate with a liquid inlet / outlet channel opened on both sides of the micro flow channel. A port substrate (silicon substrate) provided in the main body, a valve diaphragm facing the opening of the liquid inlet / outlet channel (through hole), and a pump diaphragm facing the micro channel located between the liquid inlet / outlet channels on both sides A provided valve substrate, a valve piezoelectric element that displaces the valve diaphragm to open and close the opening of the liquid in / out flow path through the packing, and a pump piezoelectric element that displaces the pump diaphragm to change the volume of the micro flow path. , And is configured.

JP-A-11-257232

  In a chemical synthesis device, a chemical analysis device, a medical analysis device, or the like using a microchip having a microchannel, a micropump for feeding a liquid at a high pressure is required because the channel resistance of the microchannel is large. In addition, since it is necessary to feed a minute amount of liquid with high accuracy, it is necessary to operate the diaphragm with respect to the minute flow path composed of the diaphragm substrate and the port substrate with high accuracy. Furthermore, chemical synthesizers, chemical analyzers, medical analyzers, etc. require chemical resistance because they use reagents with various properties.

  However, the micropump of Patent Document 1 uses a simple piezoelectric element as a drive source, and liquid feeding at high pressure is difficult. Further, Patent Document 1 does not disclose operating the diaphragm with high accuracy. In particular, when a laminated piezoelectric element is used, since the driving force increases and the thickness dimension increases, it is particularly important to consider operating the diaphragm with high accuracy. Further, the micropump of Patent Document 1 is not suitable for feeding a basic liquid because silicon and glass face the liquid contact portion.

  An object of the present invention is to provide a micropump capable of feeding a minute amount of liquid at high pressure and with high accuracy, and a method for manufacturing the same.

  Another object of the present invention is to provide a micropump capable of feeding a minute amount of liquid at high pressure and high accuracy while having chemical resistance.

  The first aspect of the present invention for achieving the above-described object is to form a microchannel between the valve substrate and the valve substrate, and to enter and exit two liquids that open on both sides of the microchannel. A port substrate provided with a flow path, two valve diaphragms facing the openings of the liquid flow channels, and a pump diaphragm facing the micro flow channel positioned between the openings of the two liquid flow paths , A valve substrate that displaces each valve diaphragm to open and close the opening of the liquid in / out channel, and a pump that displaces the pump diaphragm to change the volume of the microchannel In the micropump including the piezoelectric element, a thick wall portion having a diameter larger than the diameter of the opening portion of the liquid inlet / outlet flow path is provided in the central portion of each valve diaphragm. In the valve substrate, an independent drive part installation hole located on the anti-microchannel side of the pump diaphragm and the pump diaphragm is formed in the valve substrate, and each of the valve piezoelectric elements and the pump piezoelectric elements is formed of a laminated piezoelectric element. Each valve piezoelectric element and each pump piezoelectric element are fixed in contact with each valve diaphragm and the thick part of the pump diaphragm, respectively. In addition, the positioning pin is abutted and fixed to the other side of each of the pump piezoelectric elements, and the positioning pins are fitted and fixed in the driving portion installation holes.

A more preferable specific configuration example in the first aspect of the present invention is as follows.
(1) A flat plate-like packing made of metal that is easily deformed is installed on the surface of each valve diaphragm on the side of the minute flow path, and a ring-shaped packing made of metal that is easily deformed is installed around the opening of each flow path of liquid. What you did.
(2) A port diaphragm is provided in a portion of the port substrate facing the valve diaphragm, and the liquid inflow / outflow channels are provided so as to open in a central portion of the port diaphragm.

  In order to achieve the above, the second aspect of the present invention is a two-channel liquid flow in and out of both sides of the microchannel, which is joined to the valve substrate and forms a microchannel between the valve substrate. A port substrate provided with a path, two valve diaphragms facing the openings of the liquid inlet / outlet channels, and a pump diaphragm facing the microchannel located between the openings of the two liquid inlet / outlet channels. A provided valve substrate; two valve piezoelectric elements for displacing each valve diaphragm to open and close the opening of the liquid inlet / outlet channel; and a pump piezoelectric for displacing the pump diaphragm to change the volume of the microchannel. In the manufacturing method of the micropump including the element, a thick wall portion having a diameter larger than the diameter of the opening portion of each liquid inlet / outlet channel is formed on the valve substrate at the center portion of each valve diaphragm. In addition, the valve piezoelectric elements and the pumps constituted by the laminated piezoelectric elements are formed in the valve substrate after forming independent drive portion installation holes on the valve substrate on the anti-micro flow path side of the valve diaphragms and the pump diaphragms. Each piezoelectric element is housed in each driving portion installation hole, and one side of each of the valve piezoelectric element and the pump piezoelectric element is brought into contact with and fixed to the thick part of each of the valve diaphragm and the pump diaphragm, The positioning pins fixed in contact with the other sides of the valve piezoelectric elements and the pump piezoelectric elements are fitted and fixed in the drive portion installation holes.

A more preferable specific configuration example in the second aspect of the present invention is as follows.
(1) After the port substrate and the valve substrate are joined, the valve piezoelectric element is operated with the valve piezoelectric element fixed to the thick part of the pump diaphragm and the positioning pin, and the positioning pin Is pressed with a predetermined pressure, and the positioning pin is adhered and fixed to the valve substrate in a state where the thick part of the pump diaphragm is in contact with the port substrate.

  According to a third aspect of the present invention for achieving the above-described another object, in addition to the first aspect described above, the valve substrate and the port substrate are formed of stainless steel SUS316, and the valve substrate and the port substrate are formed. The surface which comprises the said micro flow path and the said liquid in / out flow path in a port board | substrate performs the surface treatment which has acid resistance.

A more preferable specific configuration example in the third aspect of the present invention is as follows.
(1) The flat packing and the ring packing are formed of a noble metal having chemical resistance such as gold, palladium, platinum, ruthenium, the valve substrate and the port substrate are formed of stainless steel SUS316, and the valve The surface which comprises the said microchannel in a board | substrate and the said port board | substrate performed the surface treatment which has acid resistance.

  According to the present invention, it is possible to realize a micropump capable of feeding a minute amount of liquid at high pressure with high accuracy and a method for manufacturing the micropump.

  Further, according to the present invention, it is possible to realize a micropump capable of feeding a minute amount of liquid at high pressure with high accuracy while having chemical resistance.

Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings. The same reference numerals in the drawings of the respective embodiments indicate the same or equivalent. In the present invention, the installation state of the micropump shown in each embodiment will be described as a normal installation state. However, the installation state in which the micropump is installed vertically or inverted is allowed.
(First embodiment)
A micropump and a manufacturing method thereof according to the first embodiment of the present invention will be described with reference to FIGS. The micro pump 50 of the present embodiment is particularly concerned with the micro pump driving source, valve shut-off performance, control of the passage between the diaphragm substrate and the port substrate to control the minute flow rate, the distance between the pump chamber, chemical resistance, etc. It is structured with consideration.

  The overall configuration of the micropump of this embodiment will be described with reference to FIG. FIG. 1 is a longitudinal sectional view showing a micro pump according to a first embodiment of the present invention.

  The micropump 50 of this embodiment is used for feeding a liquid (such as a reagent) of a chemical synthesizer, a chemical analyzer, a medical analyzer, or the like at a high pressure. The micropump 50 includes a port substrate 14, a valve substrate 13, a valve piezoelectric element 15 </ b> A, a pump piezoelectric element 15 </ b> B, and positioning pins 20.

  The port substrate 14 is joined to the valve substrate 13 so as to form a micro flow channel 16 between the port substrate 14 and the valve substrate 13. The joining in the present invention includes welding, adhesion, and other fixing. The microchannel 16 is formed by providing a recess in the port substrate 14. The micro flow channel 16 may be formed by providing a recess on the valve substrate 13 side, or the micro flow channel 16 may be formed by providing a recess on both the port substrate 14 and the valve substrate 13. Good. The microchannel 16 is formed to extend from side to side, the upper surface of the microchannel 16 is formed by the lower surface of the valve substrate 13, and the bottom surface of the microchannel 16 is formed by the bottom surface of the recess of the port substrate 14. In a state where the valve piezoelectric element 15A and the pump piezoelectric element 15B are not operating, the lower surface of the valve substrate 13 and the bottom surface of the recess of the port substrate 14 are parallel.

  The port substrate 14 is provided with two liquid inlet / outlet channels 19 that are located on both sides of the bottom surface of the microchannel 16 and open. In this embodiment, the fluid inflow / outflow channel 19 is configured by a vertically extending through hole. The fluid inflow / outflow channel 19 may be a liquid inflow port or a liquid outflow port depending on the operation state of the valve piezoelectric element 15A.

  The valve substrate 13 is provided with a valve diaphragm 11 facing the opening of the liquid inlet / outlet channel 19 and a pump diaphragm 12 facing the microchannel 16 positioned between the openings of the two liquid inlet / outlet channels 19. It is configured. The lower surface of the valve diaphragm 11A and the lower surface of the pump diaphragm 11B form part of the upper surface of the microchannel 16 respectively.

  Considering the chemicals used in the apparatus to which the micropump 50 of this embodiment is applied, it is necessary to have resistance mainly to acidic, basic, and organic solvents. A material that is resistant to all chemicals is a noble metal, but is expensive and difficult to apply to the entire substrate. Silicon is resistant to acidic and organic solvents, but is not applicable to basic chemicals. Therefore, in the present embodiment, stainless steel SUS316 is used as the metal material of the valve substrate 13 and the port substrate 14, so that it can be applied to chemicals such as basic and organic solvents, and the minute amounts in the valve substrate 13 and the port substrate 14 can be used. By applying a surface treatment having acid resistance to the surfaces constituting the flow path 16 and the fluid in / out flow path 19, it is possible to apply to acidic chemicals. That is, since stainless steel SUS316 has a functional group on the surface, it is possible to impart acid resistance by performing a surface treatment using this functional group. In addition, when the same surface treatment is performed on silicon, there is no resistance to basicity, which causes a problem of peeling of the surface treatment agent. Therefore, according to the configuration of the present embodiment, chemical resistance can be ensured with an inexpensive configuration and high reliability.

  A thick part 18A having a larger diameter than the diameter of the opening of the liquid inlet / outlet channel 19 is provided in an island shape at the center of the valve diaphragm 11A. The upper surface of the thick portion 18A is formed in a plane parallel to the lower surface of the thick portion 18A, and is in contact with and fixed to the lower surface of the valve piezoelectric element 15A via an adhesive 22 (see FIG. 2). When the deforming force of the valve piezoelectric element 15A is applied to the thick wall portion 18A from the upper surface, the thin wall portion around the thick wall portion 18A is bent, and the thick wall portion 18A is displaced in parallel without being bent and enters and exits the liquid. It is pressed by the opening of the channel 19. This makes it possible to reliably open and close the fluid inflow / outflow passage 19 by the valve diaphragm 11A and improve the valve closing performance. Note that the upper surface of the thick portion 18A is a completely flat surface in the present embodiment, but may be any configuration that substantially forms a flat surface and is fixed to the valve piezoelectric element 15A.

  A thick portion 18B is provided in an island shape at the center of the pump diaphragm 11B. When the deformation force of the pump piezoelectric element 15B is applied to the thick part 18B from the upper surface, the thin part around the thick part 18B is curved, and the thick part 18B is displaced in parallel without being curved. Thereby, the pump action by the pump diaphragm 11B can be performed with high accuracy. The upper surface of the thick portion 18B is formed in a plane parallel to the lower surface of the thick portion 18B, and is in contact with and fixed to the lower surface of the pump piezoelectric element 15B via an adhesive 22. Note that the upper surface of the thick portion 18B does not have to be a flat surface as long as it is configured to be substantially flat and fixed to the pump piezoelectric element 15B.

  Drive unit installation holes 12A and 12B, which are located on the anti-microchannel side of the valve diaphragm 11A and the pump diaphragm 11B, are formed in the valve substrate 13 in a vertically long shape. The wall surfaces of the drive unit installation holes 12A and 12B are formed vertically.

  The valve piezoelectric element 15 </ b> A is a drive source for displacing the valve diaphragm 11 </ b> A to open and close the opening of the fluid in / out channel 19, and is configured by a laminated piezoelectric element. By using the laminated piezoelectric element, it is possible to reliably open and close even the opening portion of the fluid inlet / outlet flow channel 19 for feeding a liquid at a high pressure. The valve piezoelectric element 15A is housed and installed in the drive portion installation hole 12A, and one side of the valve piezoelectric element 15A is fixed in contact with the thick portion 18A of the valve diaphragm 11A. The other side is fixed in contact with the positioning pin 20A. One side and the other side of the valve piezoelectric element 15A are formed in a plane parallel to the bottom surface of the recess of the port substrate 14 and the top surface of the thick portion 18A. Thereby, opening and closing of the opening part of the fluid inflow / outflow channel 19 by the valve diaphragm 11A can be accurately performed.

  The pump piezoelectric element 15B is a drive source for displacing the pump diaphragm 11B and changing the volume of the micro flow path 16 to send liquid, and is composed of a laminated piezoelectric element. By using the laminated piezoelectric element, the thickness is increased, but a large driving force can be generated, so that the liquid can be fed at a high pressure. The pump piezoelectric element 15B is housed and installed in the drive unit installation hole 12B. One side of the pump piezoelectric element 15B is fixed in contact with the thick part 18B, and the other side of the pump piezoelectric element 15B is fixed. It is fixed in contact with the positioning pins 20B. One side and the other side of the pump piezoelectric element 15B are formed in a plane parallel to the bottom surface of the recess of the port substrate 14 and the top surface of the thick portion 18B. Thereby, the liquid feeding action by the pump diaphragm 11B can be accurately performed.

  The operations of the valve piezoelectric element 15A and the pump piezoelectric element 15B are controlled by a control device (not shown). The liquid feeding operation by the valve piezoelectric element 15A and the pump piezoelectric element 15B is performed as follows.

  A voltage is applied to one valve piezoelectric element 15A to extend the laminated piezoelectric element portion, and the corresponding valve diaphragm 11A is displaced to close the fluid inlet / outlet flow path 19. In this state, a voltage is applied to the pump piezoelectric element 15B to extend the laminated piezoelectric element portion, and the liquid in the microchannel 16 is fed through the other fluid inlet / outlet channel 19. After the liquid feeding is completed, a voltage is applied to the other valve piezoelectric element 15A to extend the laminated piezoelectric element portion, and the corresponding valve diaphragm 11A is displaced to close the fluid inflow / outflow flow path 19.

  Next, the voltage application to one valve piezoelectric element 15A is stopped, the laminated piezoelectric element portion is contracted, the valve diaphragm 11A corresponding thereto is restored, and the fluid inflow / outflow passage 19 is opened. Thereafter, the voltage application to the pump piezoelectric element 15B is stopped, the laminated piezoelectric element portion is returned to its original position, and the corresponding pump diaphragm 11B is returned to its original position, thereby opening one fluid inflow / outflow channel 19 and Liquid is sucked into the microchannel 16 through the entrance / exit channel 19.

  Next, a voltage is applied to one of the valve piezoelectric elements 15A to extend the laminated piezoelectric element portion, and the corresponding valve diaphragm 11A is displaced to close the fluid inlet / outlet flow path 19. In this state, a voltage is applied to the pump piezoelectric element 15B to extend the laminated piezoelectric element portion, and the liquid in the microchannel 16 is fed through the other fluid inlet / outlet channel 19. Thereafter, by repeating this, continuous liquid feeding is performed.

  In addition, if the voltage application of the two valve piezoelectric elements 15A is reversed as described above, the liquid can be fed in the opposite direction.

  The positioning pins 20A and 20B are for determining the positions of the valve diaphragm 11A and the pump diaphragm 11B in the micro flow path 16, and are fixed to the valve piezoelectric element 15A and the pump piezoelectric element 15B and driven as described above. It fits and is fixed to the part installation holes 12A and 12B. The side walls of the positioning pins 20A and 20B are formed vertically, and the outer shape thereof is formed almost the same as the inner shape of the drive unit installation holes 12A and 12B. With the fixing structure of the positioning pins 20A and 20B, the upper and lower surfaces of the valve piezoelectric element 15A and the pump piezoelectric element 15B can be fixed in parallel with high accuracy.

  In order to improve the shut-off performance of the valve, a deformable metal flat packing 17A1 is installed on the surface of the valve diaphragm 11A on the minute flow path side, and the metal is easily deformed around the opening of the liquid in / out flow path 19. Ring-shaped packing 17A2 is installed. In other words, the flat packing 17A1 is provided at a portion of the valve diaphragm 11A that presses the opening of the fluid inlet / outlet flow path 19, and the flat packing 17A1 and the ring packing 17A2 are provided. In this way, by installing a material that is easily deformed as a packing, when the valve diaphragm 11A is pressed against the opening of the fluid inlet / outlet channel 19, the material is deformed, thereby improving the shut-off performance of the valve. Can do.

  The flat packing 17A1 and the ring packing 17A2 are made of a noble metal having chemical resistance such as gold, palladium, platinum, ruthenium. Thus, by forming only the packing portion with a noble metal, it is possible to improve the valve shut-off performance while suppressing an increase in cost.

  Next, a method for manufacturing the micropump 50 according to the present embodiment will be described.

  The valve substrate 13 is manufactured by bonding the lower substrate and the upper substrate. Specifically, the valve diaphragm 11A, the pump diaphragm 11B, and the island-shaped thick portions 18A and 18B are formed by photolithography and etching on the lower substrate, and then the valve piezoelectric element 15A and the pump piezoelectric element 15B are accommodated in the upper part. At the same time, the valve substrate 13 is manufactured by joining the drive unit installation hole 12A for fixing the positioning pins 20A and 20B and the upper substrate having the drive unit installation hole 12B. Further, after forming the micro flow channel 16 by photolithography and etching, the port substrate 14 is manufactured by forming the fluid flow channel 19. The casing of the micro pump 50 is manufactured by bonding the valve substrate 13 and the port substrate 14.

  Next, a method of assembling the valve piezoelectric element 15A, the pump piezoelectric element 15B, and the positioning pins 20 and 20B will be described with reference to FIG. FIG. 2 is a longitudinal sectional view showing an assembly process of the micropump of FIG. In the present embodiment, the valve diaphragm 11A and the pump diaphragm 11B, the thick part 18A and the thick part 18B, the valve piezoelectric element 15A and the pump piezoelectric element 15B, the positioning pin 20 and the positioning pin 20B have the same structure. Below, the alphabet of a code | symbol is abbreviate | omitted and it demonstrates by a typical example using a common name. Further, the liquid inlet / outlet channel 19 and the packings 17A1 and 17A2 are not shown.

  As shown in FIG. 2A, the laminated piezoelectric element 15 is bonded to the positioning pin 20 and the thick portion 18 using an adhesive 22. The adhesive 22 is preferably a polycyanate-based adhesive that does not absorb the amount of displacement of the laminated piezoelectric element 15. Further, the amount of displacement of the laminated piezoelectric element 15 may not be absorbed by introducing particles that do not deform into the adhesive 22.

  Thereafter, as shown in FIG. 2B, in a state where a voltage is applied to the laminated piezoelectric element 15 and the laminated piezoelectric element 15 is displaced, a predetermined pressing force F is applied to the positioning pin 20 from the upper side in parallel. The positioning pin 20 is pressed to press the diaphragm 11 against the bottom surface of the recess of the port substrate 14. The predetermined pressing force F is set to a pressing force that can reliably and accurately close the opening of the fluid in / out channel 19 by the diaphragm 11.

  After that, as shown in FIG. 2C, the positioning pin 20 is fixed to the valve substrate 13 with an adhesive 22 in a state where the positioning pin 20 is fitted in the driving portion installation hole 12 of the valve substrate 13. To do.

  Thereafter, as shown in FIG. 2D, the displacement of the laminated piezoelectric element 15 is restored by stopping the application of voltage to the laminated piezoelectric element 15. As a result, the diaphragm 11 is also returned to the original position.

By assembling in this way, it is possible to reliably displace the diaphragm 11 to the bottom surface of the microchannel 16 by the amount of displacement of the laminated piezoelectric element 15. Therefore, the micropump 50 capable of stably feeding the liquid can be manufactured.
Example 1
Next, an example of a specific manufacturing method of the micropump 50 manufactured by applying the present embodiment will be described.

  Stainless steel SUS316 resistant to basic aqueous solution and organic solvent was applied to the casing of the micropump (valve substrate 13 and port substrate 14). The valve diaphragm 11A, the pump diaphragm 11B and the island-shaped thick portions 18A and 18B in the valve substrate 13 were formed by photolithography and etching to form a valve lower substrate. Further, a portion of the valve substrate 13 to which the positioning pins 20 are fixed was drilled by machining to obtain a valve upper substrate. The valve substrate 13 was formed by bonding the valve lower substrate and the valve upper substrate.

  Further, a flat packing 17A1 was formed on the portion of the valve diaphragm 11A that presses the port substrate 14 by photolithography, sputtering, or plating. Gold was used for the material of the flat packing 17A1.

  Next, after the micro flow channel 16 of the port substrate 14 was formed by photolithography and etching, the liquid flow channel 19 was formed by machining. Similarly to the valve substrate 13, a ring-shaped packing 17 </ b> A <b> 2 was formed around the opening of the liquid inlet / outlet channel 19 by photolithography, sputtering, and plating. Gold was used for the material of the ring-shaped packing 17A2.

  The valve substrate 13 and the port substrate 14 produced by the above method were joined to produce a micropump housing.

Next, the laminated piezoelectric element 15 was fixed to the positioning pin 20 with an adhesive 22. As the adhesive 22, a polycyanate-based material was applied, and about ₂ μm of SiO ₂ particles were mixed and adhered. Next, the laminated piezoelectric element 15 is similarly fixed to the island structure 18 of the valve substrate 13 with the adhesive 22. As shown in FIG. 2, the micropump 50 was created by pressing the pin 20 with the laminated piezoelectric element 15 being displaced and fixing the pin 20 to the valve substrate 13 with a polycyanate adhesive.
(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 3 is a longitudinal sectional view of a micro pump according to a second embodiment of the present invention. The second embodiment is different from the first embodiment in the following points, and is basically the same as the first embodiment in other points.

  In the second embodiment, in order to further improve the shut-off performance of the valve, a port diaphragm 21 is provided in a portion of the port substrate 14 facing the valve diaphragm 11A, and a liquid in / out flow path is opened so as to open at the center of the port diaphragm 21. 19 is provided. By providing the port diaphragm 21, when the valve diaphragm 11 A is pressed against the opening of the liquid inlet / outlet channel 19, the port diaphragm 21 at the opening of the liquid inlet / outlet channel 19 follows this pressing. It is possible to improve the deadline performance.

  A thick portion 23 having an island structure is provided on the side of the center portion of the port diaphragm 21 opposite to the minute channel. The thick portion 23 has the same outer shape as the outer shape of the ring-shaped packing 17A2. Such a thick portion 23 can ensure a good contact state between the ring-shaped packing 17A2 and the flat-plate-shaped packing 17A1, and it is also possible to improve the shut-off performance of the valve from this point.

It is a longitudinal section showing a micro pump of a 1st embodiment of the present invention. It is a longitudinal cross-sectional view which shows the assembly process of the micropump of FIG. It is a longitudinal cross-sectional view of the micro pump of 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11A ... Valve diaphragm, 11B ... Pump diaphragm, 12 ... Drive part installation hole, 13 ... Valve board, 14 ... Port board, 15A ... Valve piezoelectric element, 15B ... Pump piezoelectric element, 16 ... Micro flow path, 17A ... Flat plate packing , 17B ... Ring-shaped packing, 18A / 18B ... Thick part, 19 ... Liquid in / out channel, 20A / 20B ... Positioning pin, 21 ... Port diaphragm, 22 ... Adhesive, 23 ... Thick part, 50 ... Micro pump .

Claims (7)

A port substrate bonded to the valve substrate to form a micro flow channel between the valve substrate and two liquid inflow / outflow channels opened on both sides of the micro flow channel;
A valve substrate provided with two valve diaphragms opposed to the openings of the liquid inlet / outlet channels and a pump diaphragm facing the minute channel located between the openings of the two liquid inlet / outlet channels;
Two valve piezoelectric elements for displacing each valve diaphragm to open and close the opening of the liquid flow path;
In a micropump comprising a pump piezoelectric element that changes the volume of the microchannel by displacing the pump diaphragm,
A thick part having a diameter larger than the diameter of the opening of the liquid inlet / outlet channel is provided at the center of each valve diaphragm,
Each valve diaphragm and the pump diaphragm are located on the anti-micro flow path side and independent drive part installation holes are formed in the valve substrate,
Each valve piezoelectric element and the pump piezoelectric element are composed of laminated piezoelectric elements and are respectively housed and installed in the drive unit installation holes,
One side of each of the valve piezoelectric elements and the pump piezoelectric elements is in contact with and fixed to the thick parts of the valve diaphragms and the pump diaphragms,
A positioning pin abuts and is fixed to the other side of each of the valve piezoelectric elements and the pump piezoelectric elements,
A micropump characterized in that each positioning pin is fitted and fixed in the drive part installation hole.   2. The micropump according to claim 1, wherein a flat plate-like packing made of metal that is easily deformed is installed on the surface of each valve diaphragm on the side of the micro flow channel, and is made of metal that is easily deformed around the opening of each liquid flow channel. A micro pump characterized by the installation of a ring-shaped packing.   3. The micropump according to claim 1, wherein a port diaphragm is provided in a portion of the port substrate facing the valve diaphragm, and the liquid inlet / outlet channels are provided so as to open at a central portion of the port diaphragm. A micropump characterized by that.   2. The micropump according to claim 1, wherein the valve substrate and the port substrate are made of stainless steel SUS316, and the surface of the valve substrate and the port substrate that forms the micro flow path and the liquid flow path is acid-resistant. A micropump characterized by being subjected to a surface treatment.   5. The micro pump according to claim 4, wherein the flat packing and the ring packing are made of a noble metal having chemical resistance such as gold, palladium, platinum, ruthenium, and the valve substrate and the port substrate are made of stainless steel SUS316. A micropump characterized by being formed and subjected to a surface treatment having acid resistance on the surfaces of the valve substrate and the port substrate that constitute the microchannel. A port substrate bonded to the valve substrate to form a micro flow channel between the valve substrate and two liquid inflow / outflow channels opened on both sides of the micro flow channel;
A valve substrate provided with two valve diaphragms opposed to the openings of the liquid inlet / outlet channels and a pump diaphragm facing the minute channel located between the openings of the two liquid inlet / outlet channels;
Two valve piezoelectric elements for displacing each valve diaphragm to open and close the opening of the liquid flow path;
In a method of manufacturing a micropump comprising a pump piezoelectric element that displaces the pump diaphragm and changes the volume of the microchannel,
A thick wall portion having a diameter larger than the diameter of the opening portion of each liquid inlet / outlet channel is formed on the valve substrate at the center of each valve diaphragm, and is positioned on the anti-microchannel side of each valve diaphragm and pump diaphragm. After forming the independent drive part installation holes in the valve substrate,
Each of the valve piezoelectric elements and the pump piezoelectric elements constituted by laminated piezoelectric elements are respectively housed in the respective drive unit installation holes, and one side of each of the valve piezoelectric elements and the pump piezoelectric elements is arranged on the valve diaphragm and the Abut against the thick part of the pump diaphragm,
Next, a positioning pin fixed in contact with the other side of each of the valve piezoelectric elements and the pump piezoelectric elements is fitted and fixed in the drive portion installation holes, and the micropump manufacturing method is characterized. . 7. The micropump manufacturing method according to claim 6, wherein after the port substrate and the valve substrate are joined, the valve piezoelectric element is fixed to the thick part of the pump diaphragm and the positioning pin. The element is operated and the positioning pin is pressed with a predetermined pressure, and the positioning pin is adhered and fixed to the valve substrate in a state where the thick part of the pump diaphragm is in contact with the port substrate. A manufacturing method of a micropump characterized by the above.

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