JP2009236284A - Microvalve and micropump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a microvalve and a micropump inexpensively produced in large quantities while having sufficient pressure tightness. <P>SOLUTION: This microvalve 6 for inflow includes: a valve element 10 formed by pressing a metal plate; a metal outer bush (a first columnar portion) 13 having a bottomed recessed portion 11 formed in one end 13a in order to store the valve element 10 and a first minute channel 12 passing from the bottom 11A of the recessed portion 11 through the other end 13b along a center axis CL; a metal inner bush (a second columnar portion ) 16 press-fitted into the recessed portion 11 together with the valve element 10 and having a second minute channel 15 passing through along the center axis CL; and a valve seat 17 arranged oppositely to the valve element 10 at the end of the second minute channel 15. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a microvalve and a micropump.

  In chemical reactions, biochemical reactions, solvent extraction, gas-liquid separation, and chemical analysis of trace components and non-contact optical analysis based on these, it is necessary to transport a small amount of fluid and control the flow rate with high accuracy. Microvalves and micropumps having a size of 1 mm or less are used. In order to realize such a micro structure, a large number of micro-valve and micro-pump structures have been proposed on the surface of a substrate such as glass by a microfabrication technique such as lithography (see, for example, Patent Document 1).

However, when silicon or glass faces the liquid contact portion, it is not suitable for feeding a basic liquid. Therefore, a substrate in which the substrate is a SUS substrate and the durability is improved by surface treatment has been proposed (for example, see Patent Document 2).
JP 2005-013980 A Japanese Patent Laid-Open No. 2006-161779

  However, since the conventional microvalve and micropump have a structure in which the substrates are joined, sufficient pressure resistance cannot be obtained depending on the pressure and flow rate of the fluid. Further, since a fine processing technique of the substrate such as lithography is required, the process is complicated and the manufacturing apparatus is expensive.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a microvalve and a micropump that have sufficient pressure resistance and can be manufactured in large quantities and at low cost.

The present invention employs the following means in order to solve the above problems.
In the microvalve according to the present invention, a valve body formed by machining a metal plate and a bottomed concave portion in which the valve body is accommodated are arranged at one end, and the central axis extends from the bottom to the other end of the concave portion. A first cylindrical column made of metal in which a first micro flow channel penetrating along the central axis and a second micro flow channel penetrating along the central axis are pressed into the recess together with the valve body. And a second cylindrical portion made of metal, and a valve seat is disposed on an end face of the first microchannel or the second microchannel so as to face the valve body.

  In the present invention, the entire body is made of metal, and the second cylindrical portion is press-fitted into the first cylindrical portion and the valve body is clamped. It can suppress suitably.

  Further, the microvalve according to the present invention is the microvalve, wherein the valve body is formed so as to protrude smoothly into a substantially hemispherical shape by pressing, and is arranged in the center of the valve body, A dome portion that communicates or blocks the first micro flow channel and the second micro flow channel according to the presence or absence of contact, and is formed in an annular shape concentric with the dome portion, and is spaced radially outward of the dome portion. And a support part sandwiched between the first cylindrical part and the second cylindrical part, a first elastic part extending in a circumferential direction of the support part, and a second elastic part extending in a radial direction. And a connecting portion connected to the dome portion and the support portion.

  According to the present invention, the rigidity of the connection portion can be adjusted according to the length of the first elastic portion. Therefore, the flow passage area corresponding to the amount of movement relative to the valve seat when the dome portion is pressed by the fluid when the valve is opened and the first elastic portion is elastically deformed can be suitably adjusted. In addition, even if the center axis of the dome portion and the center axis of the valve seat shift due to processing / assembly errors, the second elastic portion is elastically deformed when the dome portion is pressed against the valve seat when the valve is closed, The dome portion can be self-aligned with the valve seat in a direction in which both central axes coincide with each other.

Further, the microvalve according to the present invention is the microvalve, wherein the valve seat is disposed at an end portion of the second microchannel so as to face the valve body, and is directed to the first cylindrical portion side. A small recess that allows the movement of the dome within a certain range is arranged on the bottom.

  The microvalve according to the present invention is the microvalve, wherein the valve seat is disposed at an end of the first microchannel, and the movement of the dome portion toward the second cylindrical portion is constant. A small concave portion allowed within the range is arranged on an end surface of the second cylindrical portion facing the valve body.

  In the present invention, by adjusting the depth of the small concave portion, the movement amount of the dome portion when the dome portion is pressed in the flow direction can be regulated, and the flow rate when the fluid flows in the forward direction is preferable. Can be controlled.

  The microvalve according to the present invention is the microvalve, wherein an elastic layer is disposed on a surface of the valve body.

  According to the present invention, when the valve body and the valve seat are pressed against each other, the elastic layer is elastically deformed and compressed, thereby increasing the contact area between the valve body and the valve seat and further improving the sealing performance. it can.

  The microvalve according to the present invention is the microvalve, wherein the surface of the elastic layer has hydrophilicity.

  According to the present invention, the sealing force can be ensured even if the contact pressure between the valve body and the valve seat is small by increasing the resistance to the fluid flowing on the surface of the valve body.

  The microvalve according to the present invention is the microvalve, wherein the metal plate, the first cylindrical portion, and the second cylindrical portion are made of stainless steel or titanium.

  Since this invention has biocompatibility, it can be suitably used for a living body.

  The micropump according to the present invention includes a pressure chamber, at least two microchannels communicating with the pressure chamber, and the microvalve according to the present invention respectively disposed on the microchannel. Features.

  Since the present invention includes the microvalve according to the present invention, it is preferable to prevent the fluid from leaking to the outside in a state where the valve body and the valve seat are in contact with each other, and to flow in one direction of the microchannel before and after the microvalve. Can be suitably realized.

  According to the present invention, it can be manufactured in a large amount and at a low cost with sufficient pressure resistance.

An embodiment according to the present invention will be described with reference to FIGS.
The micropump 1 according to this embodiment includes a pressure chamber 2, an inflow microchannel (microchannel) 3 and an outflow microchannel (microchannel) 5 that communicate with the pressure chamber 2, and an inflow microchannel 3. An inflow microvalve (microvalve) 6 disposed above and an outflow microvalve (microvalve) 7 disposed on the outflow microchannel 5 are provided.

The pressure chamber 2 includes a diaphragm 8 and a piezoelectric element 9 connected to a drive circuit (not shown).
Since the inflow microvalve 6 and the outflow microvalve 7 have the same configuration, the details of the configuration will be described below.

The inflow microvalve 6 includes a valve body 10 formed by pressing a metal plate, a bottomed recess 11 in which the valve body 10 is accommodated at one end 13a, and the bottom 11A of the recess 11 to the other end 13b. A stainless steel or titanium out bush (first cylindrical portion) 13 in which the first microchannel 12 penetrating along the central axis CL is disposed, and the second microchannel 15 penetrating along the central axis CL. And an inbush (second cylindrical portion) 16 made of stainless steel or titanium press-fitted into the recess 11 together with the valve body 10 and the end of the second microchannel 15 facing the valve body 10. And a valve seat 17.

  The valve body 10 is formed from a thin plate made of stainless steel or titanium having a thickness of 5 μm or more and 50 μm or less by machining such as pressing. The valve body 10 is formed so as to protrude smoothly into a substantially hemispherical shape by press working, and is arranged at the center of the valve body 10. The dome portion 18 that communicates with or blocks the dome portion 15, and is formed in an annular shape that is concentric with the dome portion 18, and is spaced apart radially outward of the dome portion 18, and is sandwiched between the in bush 16 and the out bush 13. The connection part 21 which has the support part 20, the 1st elastic part 21A extended in the circumferential direction of the support part 20, and the 2nd elastic part 21B extended in radial direction, was connected to the dome part 18 and the support part 20. And.

A gold plated layer (elastic layer) 22 that has been subjected to a hydrophilic treatment is disposed on the surface of the valve body 10. The material of the plating layer is not limited to gold as long as it has elasticity and is compatible with both the fluid and the stainless steel or titanium of the base material of the valve body 10.

  The dome portion 18 and the support portion 20 are connected to each other via three connection portions 21 that are spaced apart from each other at substantially equal intervals in the circumferential direction. And the clearance gap between the dome part 18, the support part 20, and the connection part 21 becomes a fluid flow path. The first elastic portion 21A and the second elastic portion 21B are integrally formed in a leaf spring shape.

The valve seat 17 is formed on the in-bush 16 side so that the end of the second microchannel 15 protrudes toward the dome portion 18 side, and is disposed to face the dome portion 18.
In the vicinity of the end of the first microchannel 12 at the bottom 11A of the out bush 13, a small recess 23 that allows the movement of the dome 18 toward the out bush 13 within a certain range is disposed.

Next, operations of the inflow microvalve 6 and the outflow microvalve 7 and the micropump 1 according to the present embodiment will be described.
First, the piezoelectric element 9 is driven by operating a drive circuit (not shown). As a result, the diaphragm 8 is pulled upward, and the pressure chamber 2 becomes negative pressure. At this time, fluid tends to flow from the inflow microchannel 3 and the outflow microchannel 5 toward the pressure chamber 2.

  At this time, the fluid flowing into the inflow microvalve 6 from the inflow microchannel 3 flows through the second microchannel 15 and presses the dome portion 18 of the valve body 10 toward the first microchannel 12 side. At this time, the connection portion 21 of the valve body 10 is elastically deformed, and the dome portion 18 moves away from the valve seat 17 toward the small recess 23. As a result, the inflow microvalve 6 is opened, and the fluid passes through the first microchannel 12 and flows into the pressure chamber 2.

  On the other hand, the fluid flowing into the outflow microvalve 7 from the outflow microchannel 5 flows through the first microchannel 12 and presses the dome 18 toward the valve seat 17. At this time, the connecting portion 21 of the valve body 10 is elastically deformed and the dome portion 18 is pressed against the valve seat 17. Since the gold plated layer 22 is disposed on the surface of the valve body 10, the valve seat 17 bites into the plated layer 22 and the surface pressure is further increased. Therefore, the outflow microvalve 7 is closed, and the fluid does not flow to the second microchannel 15.

  Subsequently, the drive circuit is operated again to drive the piezoelectric element 9 in the direction opposite to the above. As a result, the diaphragm 8 is pushed downward and the pressure in the pressure chamber 2 rises. At this time, the fluid in the pressure chamber 2 tends to flow into the inflow microvalve 6 and the outflow microvalve 7.

  At this time, the fluid flowing into the second microchannel 15 of the outflow microvalve 7 presses the dome portion 18 toward the first microchannel 12 side. At this time, the connecting portion 21 of the valve body 10 is elastically deformed, and the dome portion 18 is separated from the valve seat 17 and moves toward the small recess 23. As a result, the outflow microvalve 7 is opened, and the fluid passes through the first microchannel 12 and flows into the outflow microchannel 5.

  On the other hand, the fluid that has flowed into the first microchannel 12 of the inflow microvalve 6 flows through the first microchannel 12 and presses the dome 18 toward the valve seat 17. At this time, the connecting portion 21 of the valve body 10 is elastically deformed and the dome portion 18 is pressed against the valve seat 17. Since the gold plated layer 22 is disposed on the surface of the valve body 10, the valve seat 17 bites into the plated layer 22 and the surface pressure is further increased. Therefore, the inflow microvalve 6 is closed and the fluid does not flow to the second microchannel 15.

  By repeating this operation, the fluid flows from the inflow microchannel 3 to the outflow microchannel 5 through the inflow microvalve 6, the pressure chamber 2, and the outflow microvalve 7.

  According to the inflow microvalve 6 and the outflow microvalve 7, the whole is made of metal, and the inbush 16 is press-fitted into the outbush 13 so that the valve body 10 is sandwiched. In a state in which the contact with each other is sufficient, and leakage of the fluid to the outside of the valve can be suitably suppressed. In addition, since it is made of metal, it can be manufactured in a larger amount and at a lower cost than conventional methods.

  In particular, since the valve body 10 includes the dome portion 18, the dome portion 18 and the valve seat 17 can be brought into contact with each other in a curved surface, like a valve having a visible size, and a more reliable opening / closing state can be achieved. Can be realized.

Moreover, the rigidity of the connection part 21 can be adjusted according to the length of 21 A of 1st elastic parts in the valve body 10. FIG. Accordingly, the flow passage area corresponding to the amount of movement with respect to the valve seat 17 when the dome portion 18 is pressed by the fluid when the valve is opened and the first elastic portion 21A is elastically deformed is preferably adjusted based on the relationship with the flow rate. Can do. Even if the dome 18 and the valve seat 17 are decentered due to processing / assembly errors or the like, the second elastic portion 21B is elastically deformed when the dome 18 is pressed against the valve seat 17 when the valve is closed, so that the valve The dome portion 18 can be self-aligned in a direction in which the center axes of the two automatically coincide with the seat.

  Further, since the small concave portion 23 is disposed on the bottom portion 11A of the concave portion 11, the movement amount of the dome portion 18 with respect to the flow direction can be regulated by adjusting the depth of the small concave portion 23, so that the fluid flows in order. The flow rate when flowing in the direction can be suitably controlled.

  In addition, since the gold plating layer 22 is disposed on the surface of the valve body 10, when the dome portion 18 and the valve seat 17 are brought into pressure contact, the plating layer 22 is elastically deformed and compressed, so that the dome portion The contact area between 18 and the valve seat 17 can be increased to further improve the sealing performance.

At this time, since the plating layer 22 is gold, the corrosion resistance can be improved without being limited to acids and alkalis. In addition, since the plated layer 22 has a small surface roughness, the hydrophilicity can be enhanced. Further, since gold is originally hydrophilic and has been subjected to a hydrophilic treatment, the resistance of the fluid flowing on the surface of the valve body 10 is improved. Can be increased. Therefore, even if the contact pressure between the dome portion 18 and the valve seat 17 is small, high sealing performance can be ensured.

  Further, since both the inflow microvalve 6 and the outflow microvalve 7 are made of stainless steel or titanium, they have a high affinity with a living body and can be sufficiently used for a living body.

  In addition, according to the micropump 1, since the inflow microvalve 6 and the outflow microvalve 7 described above are provided, the one-way flow in the inflow microchannel 3 and the outflow microchannel 5 before and after the microvalve is preferable. Can be realized.

The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, in the above embodiment, the valve seat 17 is formed on the in-bush 16 side so as to partially protrude on the dome portion 18 side, and is disposed on the end surface of the second microchannel 15. In addition, a small concave portion 23 that allows the movement of the dome portion 18 toward the out bush 13 within a certain range is disposed on the bottom portion 11 </ b> A of the out bush 13.

  However, the present invention is not limited to this, and the valve seat is arranged at the end of the flow path at the bottom of the recess of the out bush, and the small recess that allows the movement of the dome portion to the in bush side within a certain range has an You may distribute | arrange to the flow-path end of a bush. At this time, when the valve is open, the fluid flows from the first microchannel toward the second microchannel.

  The gold plating layer 22 is not limited to the valve body 10 and may be applied to the surfaces of the out bush 13 and the in bush 16. Thereby, sealing performance can be improved more.

  As shown in FIG. 4, the stage S connected to the stage controller SC, the bush B mounted on the stage S, the vacuum pump VP connected to the valve V, and the valve V and the bush B A device E that includes a syringe pump SP that supplies liquid, a pressure gauge P that detects the supply pressure of the liquid, and a load cell R that is connected to the amplifier A and that can adjust the distance between the valve V and the bush B is used. Then, the flow resistance value between the two was measured, and the sealing performance by gold plating was compared. At this time, (1) untreated, (2) soft gold plating layer only, (3) soft gold plating layer and hydrophilic treatment, (4) soft gold plating layer and hydrophobic treatment, 5) Only the hard gold plating layer was subjected to (6) hard gold plating layer and hydrophilic treatment, and (7) hard gold plating layer and hydrophobic treatment. The test results are shown in FIG.

  It was found that the gold-plated layer subjected to hydrophilic treatment has the highest flow resistance and high sealing performance.

It is sectional drawing in the central axis which shows the micropump which concerns on one Embodiment of this invention. It is sectional drawing in the central axis which shows the microvalve which concerns on one Embodiment of this invention. It is a top view which shows the valve body which concerns on one Embodiment of this invention. It is a schematic diagram which shows the performance test apparatus of the microvalve in the Example of this invention. It is a graph which shows the test result using the apparatus of FIG.

Explanation of symbols

1 Micropump 2 Pressure chamber 3 Inflow microchannel (microchannel)
5 Outflow microchannel (microchannel)
6 Micro valve for inflow (micro valve)
7 Micro valve for outflow (micro valve)
DESCRIPTION OF SYMBOLS 10 Valve body 11 Concave part 12 1st microchannel 13 Out bush (1st cylindrical part)
13a one end 13b other end 15 second microchannel 16 in bush (second cylindrical portion)
17 valve seat 18 dome part 20 support part 21 connection part 21A first elastic part 21B second elastic part 22 plating layer (elastic layer)
23 Small recess

Claims (8)

A valve body formed by machining a metal plate;
A metal first cylindrical portion in which a bottomed concave portion in which the valve body is accommodated is arranged at one end, and a first microchannel that penetrates along the central axis from the bottom portion to the other end of the concave portion is disposed; ,
A second micro-fluidic channel penetrating along the central axis, and a metal second cylindrical portion press-fitted into the recess together with the valve body;
With
A microvalve characterized in that a valve seat is arranged on an end face of the first microchannel or the second microchannel so as to face the valve body. The valve body is
It is formed in a substantially hemispherical shape by a pressing process so as to protrude smoothly and is arranged in the center of the valve body. The first microchannel and the second microchannel are communicated or blocked depending on the presence or absence of contact with the valve seat. The dome part to be
A support portion that is formed in an annular shape concentric with the dome portion and is spaced apart radially outward of the dome portion, and is sandwiched between the first cylindrical portion and the second cylindrical portion;
A first elastic portion extending in a circumferential direction of the support portion, and a second elastic portion extending in a radial direction, the connection portion connected to the dome portion and the support portion;
The micro valve according to claim 1, comprising: The valve seat is disposed at the end of the second microchannel so as to face the valve body,
The microvalve according to claim 2, wherein a small concave portion that allows the movement of the dome portion toward the first cylindrical portion within a certain range is arranged on the bottom portion. The valve seat is disposed at an end of the first microchannel;
3. A small concave portion that allows movement of the dome portion toward the second cylindrical portion within a certain range is disposed on an end surface of the second cylindrical portion facing the valve body. The microvalve described in 1.   The microvalve according to any one of claims 1 to 4, wherein an elastic layer is disposed on a surface of the valve body.   The microvalve according to claim 5, wherein a surface of the elastic layer has hydrophilicity.   The microvalve according to claim 1, wherein the metal plate, the first cylindrical portion, and the second cylindrical portion are made of stainless steel or titanium. A pressure chamber;
At least two microchannels in communication with the pressure chamber;
The microvalve according to any one of claims 1 to 7, each disposed on the microchannel,
A micropump characterized by comprising:

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