Memory alloy microvalve for microfluidics

Abstract

The utility model discloses a memory alloy micro valve for microfluidics. The memory alloy micro valve comprises a chip, a memory alloy sheet and a heat conduction piece, a microfluidic channel is arranged in the chip, and a memory alloy sheet is arranged in a branch intersection of the microfluidic channel; the memory alloy sheet in the unheated state blocks the branch intersection of the microfluidic channel, and the memory alloy sheet is connected with the heat conduction piece; the heat conduction piece is used for transferring heat to the memory alloy sheet, so that the memory alloy sheet deforms and the blocking of the intersection of the microfluidic channel branches is relieved; according to the scheme, the double-pass phase-change temperature is achieved, three-state deformation can be achieved, therefore, opening and closing control over the micro-flow channel is achieved, the response time is greatly shortened, the structure is simple, and integration is easy.

Description

Technical Field

[0001] The utility model relates to the technical field of microvalves, in particular to a memory alloy microvalve used for microfluidics. Background Art

[0002] Microvalve technology has been widely researched and applied in fields such as biology, chemistry, and medicine. Currently, microvalves used in microfluidic chips are divided into active and passive microvalves, but the microvalves currently on the market still have the following problems:

[0003] 1. Requirements for microvalve sealing performance: Insufficient pre-tightening force will cause leakage, while excessive pre-tightening force will easily cause failure;

[0004] 2. Active driving may affect biochemical reactions and is difficult to process and integrate;

[0005] 3. The processing cost is high, the structure is complex, and the response speed is low.

[0006] Therefore, a device with high reliability, strong versatility, low cost, and the basic features of self-sealing and multi-channel is needed so that it can play a greater role. Utility Model Content

[0007] The purpose of the utility model is to provide a memory alloy microvalve for microfluidics, which has high reliability, strong versatility and low cost, and has the basic characteristics of self-sealing and multi-channel, so that it can play a greater role.

[0008] In order to solve the above technical problems, the utility model provides a memory alloy microvalve for microfluidics, including a chip, a memory alloy sheet and a heat conductor; a microfluidic channel is provided in the chip, and the branch intersection of the microfluidic channel is provided with the memory alloy sheet; the memory alloy sheet in an unheated state blocks the branch intersection of the microfluidic channel, and the memory alloy sheet is connected to the heat conductor; the heat conductor is used to transfer heat to the memory alloy sheet to cause the memory alloy sheet to deform and release the blockage of the branch intersection of the microfluidic channel.

[0009] In one embodiment, the microfluidic channel is a two-phase three-way channel structure.

[0010] In one embodiment, the microfluidic channel includes a main circuit, a first branch and a second branch connected to the input end of the main circuit, a third branch and a fourth branch connected to the input end of the first branch, a fifth branch and a sixth branch connected to the input end of the second branch, and a seventh branch whose output end is connected to the input ends of the fourth branch and the fifth branch.

[0011] In one embodiment, the memory alloy sheet includes a first memory alloy sheet and a second memory alloy sheet; the first memory alloy sheet is arranged at the intersection of the first branch, the third branch and the fourth branch; the second memory alloy sheet is arranged at the intersection of the second branch, the fifth branch and the sixth branch.

[0012] In one embodiment, the heat conductor includes a first heat conductor and a second heat conductor, and the first heat conductor and the second heat conductor are both placed outside the microfluidic channel; the first heat conductor is connected to the first memory alloy sheet; and the second heat conductor is connected to the second memory alloy sheet.

[0013] In one embodiment, the memory alloy sheet is connected to a heat-conducting rod, and the heat-conducting rod extends out of the microfluidic channel and is connected to the heat-conducting member.

[0014] In one embodiment, the unheated memory alloy sheet is an arc-shaped sheet, the concave arc position of the memory alloy sheet faces the incoming flow direction of the microfluidic channel, and the memory alloy sheet abuts and seals against the inner wall of the microfluidic channel.

[0015] In one embodiment, the memory alloy sheet is nickel-titanium memory alloy.

[0016] In one embodiment, the memory alloy microvalve further includes a heat generating mechanism, and the heat generating mechanism is used to supply heat to the heat conducting member.

[0017] In one embodiment, the heat generating mechanism is a laser generator.

[0018] The beneficial effects of the utility model are as follows:

[0019] The above-mentioned memory alloy sheet has a fast response speed, high damping and high elasticity, is shape-functional and corrosion-resistant, and can meet the application requirements of engineering and medicine. At the same time, it has a two-way phase change temperature and can have three states of deformation to achieve the open and closed control of the microfluidic channel, greatly shortening the response time, with a simple structure and easy integration. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solution of the present invention, the following is a brief introduction to the drawings required for use in the implementation. Obviously, the drawings described below are only some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1 It is a structural diagram provided by an embodiment of the present utility model;

[0022] Figure 2 yes Figure 1 Schematic diagram of the structure of the memory alloy sheet;

[0023] Figure 3 yes Figure 1 Schematic diagram of the heat conducting component structure;

[0024] Figure 4 yes Figure 1 Schematic diagram of the memory alloy sheet in the open state;

[0025] Figure 5 yes Figure 1 Schematic diagram of the memory alloy sheet in the contraction state.

[0026] The reference numerals are as follows:

[0027] 10. Chip; 11. Microfluidic channel; 110. Main channel; 111. First branch channel; 112. Second branch channel; 113. Third branch channel; 114. Fourth branch channel; 115. Fifth branch channel; 116. Sixth branch channel; 117. Seventh branch channel;

[0028] 20. Memory alloy sheet; 21. First memory alloy sheet; 22. Second memory alloy sheet; 23. Heat conducting rod;

[0029] 30. Heat conducting member; 31. First heat conducting member; 32. Second heat conducting member. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present invention.

[0031] The utility model provides a memory alloy microvalve for microfluidics, which is implemented as follows: Figures 1 to 3 As shown, it includes a chip 10 , a memory alloy sheet 20 and a heat conducting member 30 .

[0032] Regarding the chip 10, Figure 1 and Figure 2 As shown, the chip 10 of this embodiment is roughly rectangular, and a microfluidic channel 11 is provided in the chip 10. A memory alloy sheet 20 is provided at the intersection of the branches of the microfluidic channel 11. There are many options for the arrangement of the microfluidic channel 11, but it should be ensured that it has corresponding main and branch structures to achieve convergence.

[0033] For example, in this embodiment, the microfluidic channel 11 is set as a two-phase three-way channel structure. This type of structure mainly uses two branches and one main form to achieve the connection of three channels to ensure that the two branches can achieve convergence output.

[0034] Specific as Figure 1As shown, the microfluidic channel 11 at this time includes a main path 110, a first branch 111 and a second branch 112 connected to the input end of the main path 110, a third branch 113 and a fourth branch 114 connected to the input end of the first branch 111, a fifth branch 115 and a sixth branch 116 connected to the input end of the second branch 112, and a seventh branch 117 whose output end is connected to the input ends of the fourth branch 114 and the fifth branch 115.

[0035] Regarding the memory alloy sheet 20, it is used to realize the on-off control of the micro-channel 11, such as Figures 1 to 5 As shown, the memory alloy sheet 20 of this embodiment is connected to the heat conductor 30 to fix the installation position of the memory alloy sheet 20; and when the memory alloy sheet 20 is in an unheated state, the memory alloy sheet 20 is in an open state as a whole, so the memory alloy sheet 20 in the unheated state can block the branch intersection of the microfluidic channel 11.

[0036] In order to ensure that the memory alloy sheet 20 is firmly installed, Figures 1 to 5 As shown, in this embodiment, the memory alloy sheet 20 is connected to a heat-conducting rod 23, and the heat-conducting rod 23 passes through the outside of the microfluidic channel 11 and is connected to the heat-conducting member 30. At this time, the memory alloy sheet 20 can be connected to the heat-conducting member 30 by plugging using the heat-conducting rod 23, which not only makes the installation simple, but also ensures the firmness of the installation.

[0037] In addition, the memory alloy sheet 20 utilizes its full contact with the microchannel 11 in the unheated state to achieve a tight sealing of the microchannel 11. Therefore, in order to ensure that the memory alloy sheet 20 has a better sealing ability, Figure 1 and Figure 2 As shown, in this embodiment, the memory alloy sheet 20 in the unheated state is arranged as an arc-shaped sheet, and the concave arc position of the memory alloy sheet 20 faces the incoming flow direction of the microchannel 11, so the memory alloy sheet 20 can abut and seal against the inner wall of the microchannel 11, thereby achieving the blocking of the microchannel 11 by the memory alloy sheet 20.

[0038] After adopting this setting, even if fluid flows in the microchannel 11 and impacts the memory alloy sheet 20, since the memory alloy sheet 20 uses a concave arc surface to face the flow, the impact force generated by the fluid will only cause the memory alloy sheet 20 to expand further, thereby strengthening the abutment and sealing between the memory alloy sheet 20 and the microchannel 11.

[0039] Furthermore, since nickel-titanium memory alloy has a fast response speed, high damping and high elasticity, shape function and corrosion resistance, it can meet the application requirements of engineering and medicine. At the same time, it has a two-way phase change temperature and can have three states of deformation to achieve the open and closed control of the microfluidic channel, greatly shortening the response time, simple structure, and easy integration, so this embodiment sets the memory alloy sheet 20 to be nickel-titanium memory alloy.

[0040] For example, when the temperature increases to the set temperature of the material, the material will deform rapidly. The phase change temperatures of nickel-titanium alloy materials are 20-40 degrees, 45-90 degrees, and 5-15 degrees, and the elongation is 25-50%. The response temperature of both phases can be controlled below 100 degrees, which not only saves the energy required for microvalve deformation, but also greatly reduces the response time of microvalve deformation. The phase change time can reach as fast as 0.01s, and at the phase change temperature, the alloy produces continuous and soft tension, which plays a long-term supporting role and can ensure the rapid passage of fluid.

[0041] Furthermore, in this embodiment, there are two locations where the microfluidic channel 11 needs to be open and closed, so Figure 1 and Figure 2 As shown, this embodiment provides a memory alloy sheet 20 including a first memory alloy sheet 21 and a second memory alloy sheet 22. The first memory alloy sheet 21 is arranged at the intersection of the first branch 111, the third branch 113 and the fourth branch 114, and the second memory alloy sheet 22 is arranged at the intersection of the second branch 112, the fifth branch 115 and the sixth branch 116, that is, the separate opening and closing control of the two positions is realized by the first memory alloy sheet 21 and the second memory alloy sheet 22.

[0042] Regarding the heat conducting member 30, Figures 1 to 5 As shown, the heat conducting member 30 is used to transfer heat to the memory alloy sheet 20 , so as to deform the memory alloy sheet 20 and release the blockage of the intersection of the branches of the microfluidic channel 11 .

[0043] Since there are two memory alloy sheets 20, in order to realize the separate control of the two memory alloy sheets 20, as shown in FIG. Figure 1 and Figure 3 As shown, in this embodiment, the heat conducting member 30 includes a first heat conducting member 31 and a second heat conducting member 32, and the first heat conducting member 31 and the second heat conducting member 32 are both placed outside the microfluidic channel 11; the first heat conducting member 31 is connected to the first memory alloy sheet 21; the second heat conducting member 32 is connected to the second memory alloy sheet 22.

[0044] Therefore, if the deformation of the first memory alloy sheet 21 needs to be controlled, the first heat conductor 31 only needs to be heated to transfer heat to the first memory alloy sheet 21 so that the first memory alloy sheet 21 contracts and deforms, thereby releasing the blockage of the microchannel 11 by the first memory alloy sheet 21.

[0045] Similarly, if the second memory alloy sheet 22 needs to be controlled to deform, the second heat conductor 32 only needs to be heated to transfer heat to the second memory alloy sheet 22 so that the second memory alloy sheet 22 contracts and deforms, thereby releasing the blockage of the microchannel 11 by the second memory alloy sheet 22.

[0046] It should also be pointed out that the source of heat can utilize existing external equipment in conjunction with the above-mentioned memory alloy microvalve, or the above-mentioned memory alloy microvalve can be provided with a heat generating mechanism, which is used to supply heat to the heat conductor 30. For example, providing the heat generating mechanism as a laser generator is a preferred method.

[0047] In order to better reflect the working principle of the above-mentioned memory alloy microvalve, the following will be explained in combination with specific application scenarios.

[0048] Assuming that the memory alloy microvalve is in the initial default state at this time, the first memory alloy sheet 21 and the second memory alloy sheet 22 are fully opened, so that the intersection of the first branch 111, the third branch 113 and the fourth branch 114, and the intersection of the second branch 112, the fifth branch 115 and the sixth branch 116 are all in a blocked state.

[0049] If it is necessary to control the intersection of the first branch 111, the third branch 113 and the fourth branch 114 to be unblocked, the laser generator is controlled to irradiate the first heat conductor 31. At this time, heat will be generated on the first heat conductor 31 and transferred to the first memory alloy sheet 21, so that the first memory alloy sheet 21 will be deformed and contracted, thereby releasing the contact between the first memory alloy sheet 21 and the microfluidic channel 11, so that the fluid can flow smoothly through the intersection of the first branch 111, the third branch 113 and the fourth branch 114.

[0050] Similarly, if it is necessary to control the intersection of the second branch 112, the fifth branch 115 and the sixth branch 116 to be unblocked, the laser generator is controlled to irradiate the second heat conductor 32. At this time, heat will be generated on the second heat conductor 32 and transferred to the second memory alloy sheet 22, so that the second memory alloy sheet 22 will deform and shrink, thereby releasing the contact between the second memory alloy sheet 22 and the microfluidic channel 11, so that the fluid can flow smoothly through the intersection of the second branch 112, the fifth branch 115 and the sixth branch 116.

[0051] When the first memory alloy sheet 21 and the second memory alloy sheet 22 need to be controlled, it is only necessary to stop the laser generator from irradiating.

[0052] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A memory alloy microvalve for microfluidics, characterized in that: Including chips, memory alloy sheets and thermal conductive parts; A microfluidic channel is provided in the chip, and the memory alloy sheet is provided at the intersection of the branches of the microfluidic channel; The memory alloy sheet in an unheated state blocks the branch intersection of the microfluidic channel, and the memory alloy sheet is connected to the heat conducting member; The heat conducting member is used to transfer heat to the memory alloy sheet, so as to deform the memory alloy sheet and release the blockage of the intersection of the microfluidic channel branches.

2. The memory alloy microvalve according to claim 1, characterized in that: The microfluidic channel is a two-phase three-way channel structure.

3. The memory alloy microvalve according to any one of claims 1 or 2, characterized in that: The microfluidic channel includes a main channel, a first branch and a second branch connected to the input end of the main channel, a third branch and a fourth branch connected to the input end of the first branch, a fifth branch and a sixth branch connected to the input end of the second branch, and a seventh branch whose output end is connected to the input ends of the fourth branch and the fifth branch.

4. The memory alloy microvalve according to claim 3, characterized in that: The memory alloy sheet includes a first memory alloy sheet and a second memory alloy sheet; The first memory alloy sheet is provided at the intersection of the first branch, the third branch and the fourth branch; The second memory alloy sheet is arranged at the intersection of the second branch, the fifth branch and the sixth branch.

5. The memory alloy microvalve according to claim 4, characterized in that: The heat conducting member includes a first heat conducting member and a second heat conducting member, wherein the first heat conducting member and the second heat conducting member are both placed outside the microfluidic channel; The first heat conducting member is connected to the first memory alloy sheet; The second heat conducting member is connected to the second memory alloy sheet.

6. The memory alloy microvalve according to claim 1, characterized in that: The memory alloy sheet is connected with a heat conducting rod, and the heat conducting rod passes through the outside of the micro-fluidic channel and is connected with the heat conducting member.

7. The memory alloy microvalve according to claim 1, characterized in that: The memory alloy sheet in an unheated state is an arc-shaped sheet, the concave arc position of the memory alloy sheet faces the incoming flow direction of the microfluidic channel, and the memory alloy sheet abuts and seals against the inner wall of the microfluidic channel.

8. The memory alloy microvalve according to claim 1, characterized in that: The memory alloy sheet is nickel-titanium memory alloy.

9. The memory alloy microvalve according to claim 1, characterized in that: The memory alloy microvalve further includes a heat generating mechanism, which is used to supply heat to the heat conducting member.

10. The memory alloy microvalve according to claim 9, characterized in that: The heat generating mechanism is a laser generator.

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