Pump chamber structure and micropump thereof

Abstract

The utility model provides a kind of pump cavity structure and its micropump, the pump cavity structure in it includes cavity and branch channel, one end of branch channel is communicated with pump cavity, and the other end of branch channel is used to connect one-way valve;The number of branch channel is multiple, and the other end of multiple branch channels is uniformly circumferentially arrayed distribution with the axis of one-way valve as reference point.In the scheme, by setting multiple branch channels, and making the other end of each branch channel uniformly circumferentially arrayed distribution, the liquid flowed out of one-way valve can be uniformly dispersed, the uniformity of liquid flow is improved, to maintain the force balance of support structure, avoid the damage of cantilever beam, thereby improve the service life of micropump.

Description

Technical Field

[0001] This utility model relates to the field of fluid transport equipment, specifically to a pump chamber structure and its micropump. Background Technology

[0002] like Figures 1 to 3 As shown, the prior art micropump includes a top glass 11, a silicon wafer 12, and a bottom glass 13. The silicon wafer 12 is disposed between the top glass 11 and the bottom glass 13. A pump chamber 14 is provided on the side of the silicon wafer 12 closest to the top glass 11, and a pump diaphragm 15 is formed below the pump chamber 14. A liquid inlet 16 is provided on the bottom glass 13, and a liquid inlet channel 17 is provided on the silicon wafer 12 to connect the liquid inlet 16 and the pump chamber 14. A liquid inlet check valve 18 is provided in the liquid inlet channel 17. A liquid outlet 19 is provided on the top glass 11, and a liquid outlet channel 20 is provided on the silicon wafer 12 to connect the liquid outlet 19 and the pump chamber 14. A liquid outlet check valve 21 is provided in the liquid outlet channel 20. The piezoelectric ceramic drives the pump diaphragm 15 to reciprocate vertically through a transmission structure to change the volume of the pump chamber 14 and realize the pumping of liquid.

[0003] In existing micropump structures, the pump chamber 14 is directly connected to the inlet check valve 18. At this point, the junction of the inlet check valve 18 and the pump chamber 14 forms an annular through-hole 22, which is used for liquid flow. When pumping liquid, the flow velocity is faster on the side of the through-hole 22 closer to the center of the pump chamber 14, and slower on the side farther from the center. Over long-term use, this can easily cause the support structure 26 of the inlet check valve 18 to tilt due to unbalanced forces, preventing the inlet check valve 18 from fully returning to its original position. (See reference for details.) Figure 3 It is clear that this solution affects the service life of the inlet check valve 18.

[0004] In existing patents, such as the one with publication number CN119373700A and titled "MEMS Microvalve and Micropump," the pump chamber in this design is an integral structure, and the annular flow channel at the top of the one-way valve is connected to the pump chamber at every point. In this design, the flow velocity is faster on the side of the annular through-hole at the top of the inlet one-way valve closer to the center of the pump chamber, while the flow velocity is slower on the side of the annular through-hole farther from the center of the pump chamber. This causes an imbalance in the force on the support structure of the one-way valve in this design. The support structure in this design is a cantilever beam, and the cantilever beam in this design is prone to deformation and breakage, thus affecting the service life of the micropump.

[0005] In summary, this application aims to address the problem of uneven liquid flow rate causing stress imbalance in the support structure of the one-way valve. Utility Model Content

[0006] To solve the above-mentioned technical problems, this utility model proposes a pump chamber structure and its micropump. In this solution, by setting multiple branch channels and distributing the other end of each branch channel in a uniform circumferential array, the liquid flowing out of the one-way valve can be uniformly dispersed, improving the uniformity of liquid flow. This helps maintain the stress balance of the support structure, avoids damage to the cantilever beam, and thus improves the service life of the micropump.

[0007] Specifically, this utility model proposes a pump chamber structure, including a chamber and a branch channel, one end of which is connected to the chamber and the other end of which is used to connect a one-way valve;

[0008] The number of the branch channels is multiple, and the other ends of the multiple branch channels are evenly distributed in a circular array with the axis of the one-way valve as the reference.

[0009] Preferably, the number of the branch channels is two or three.

[0010] In addition, this application proposes a micropump including the above-described pump chamber structure, wherein the one-way valve includes a valve body and a support structure, and the valve body is installed in the inlet or outlet flow channel of the micropump through the support structure.

[0011] Preferably, the support structure is an annular connecting part, and the annular connecting part is provided with a through hole.

[0012] Preferably, the supporting structure is a cantilever beam.

[0013] Furthermore, the number of cantilever beams is multiple.

[0014] Furthermore, reinforcing ribs are provided between adjacent cantilever beams.

[0015] Furthermore, the reinforcing bars between adjacent cantilever beams can be single or multiple.

[0016] Furthermore, the reinforcing rib is either straight or curved.

[0017] Furthermore, the cantilever beam on the valve body is one or more combinations of straight, broken, bifurcated, and curved shapes.

[0018] Furthermore, the connection between the silicon wafer of the micropump and the cantilever beam is provided with a clearance groove, which is located below the cantilever beam. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0020] Figure 1 This is a schematic diagram of the internal structure of a micropump in the prior art;

[0021] Figure 2 yes Figure 1 A cross-sectional view along the AA direction;

[0022] Figure 3 This is a schematic diagram of the impact of water flow on the inlet check valve in the prior art;

[0023] Figure 4 This is a three-dimensional structural diagram of the one-way valve when the supporting structure is an annular connecting part in this embodiment;

[0024] Figure 5 This is a three-dimensional structural diagram of the one-way valve when a through hole is added to the annular connecting part in this embodiment;

[0025] Figure 6 This is a three-dimensional structural diagram of the one-way valve when there are three cantilever beams in this embodiment;

[0026] Figure 7 This is a three-dimensional structural diagram of the one-way valve when a reinforcing rib is set between adjacent cantilever beams in this embodiment;

[0027] Figure 8 This is a three-dimensional structural diagram of the one-way valve when multiple reinforcing ribs are provided between adjacent cantilever beams in this embodiment;

[0028] Figure 9 This is a three-dimensional structural diagram of the one-way valve when the cantilever beam is of the broken line shape in this embodiment;

[0029] Figure 10 This is a schematic diagram of the liquid flow direction between the check valve and the branch channels when there are two branch channels in this embodiment;

[0030] Figure 11 This is a schematic diagram showing the connection relationship between the branch channels and the cavities of the pump chamber structure when there are three branch channels in this embodiment.

[0031] The reference numerals used in the attached figures are as follows:

[0032] 11-Top glass; 12-Silicon wafer; 13-Bottom glass; 14-Pump chamber; 15-Drive pump diaphragm; 16-Inlet; 17-Inlet channel; 18-Inlet check valve; 19-Outlet; 20-Outlet channel; 21-Outlet check valve; 22-Through port; 23-Cavity; 24-Branch channel; 25-Valve body; 26-Support structure; 27-Annular connection; 28-Through hole; 29-Cantilever beam; 30-Reinforcing rib; 31-Reserved space; 32-Allowing groove. Detailed Implementation

[0033] The technical solutions of this application will be further described below with reference to specific embodiments, but this application is not limited to these embodiments.

[0034] like Figure 10 and Figure 11 As shown, this embodiment proposes a pump chamber structure, including a chamber 23 and a branch channel 24. One end of the branch channel 24 is connected to the chamber 23, and the other end of the branch channel 24 is used to connect a one-way valve.

[0035] The number of the branch channels 24 is multiple, and the other ends of the multiple branch channels 24 are evenly distributed in a circular array with the axis of the one-way valve as the reference.

[0036] In this scheme, by setting multiple branch channels 24 and distributing the other end of each branch channel 24 in a uniform circumferential array, the liquid flowing out of the one-way valve can be uniformly dispersed, improving the uniformity of liquid flow. This helps maintain the force balance of the support structure 26, avoids damage to the cantilever beam 29, and thus improves the service life of the micro pump.

[0037] like Figure 9 and Figure 10 As shown, the number of branch channels 24 in this scheme can be set to two, in which case, as follows: Figure 9 As shown, the cantilever beam 29 is a polygonal shape with two inflection points. The effective length of the cantilever beam 29 along the radial direction of the check valve is reduced, effectively avoiding the adhesion effect that may occur during the opening and closing of the check valve. This ensures that the cantilever beam 29 can open and close flexibly and reliably, improving the operational reliability of the check valve. In existing technologies, the impact force of the fluid on the right side of the inlet check valve is greater than that on the left side. When the flow velocity is high, the valve body 25 will tilt significantly and cannot return to its normal position when the forward fluid disappears, failing to cover the orifice of the inlet 16. Compared to existing technologies, this solution improves upon the existing technology by using a symmetrical dual-channel design, enhancing the flow velocity tolerance limit of the check valve.

[0038] Or such as Figure 11 As shown, the number of branch channels 24 is set to three, which can be used in conjunction with a check valve with three cantilever beams 29. The notches between adjacent cantilever beams 29 are connected one-to-one with the branch channels 24. This ensures the force balance of the check valve and enhances its flow velocity resistance limit.

[0039] like Figure 11As shown, in the three branch channels 24 between the annular through-port 22 and the cavity 23 of the one-way valve, the upper and lower branch channels 24 are bent structures, while the middle branch channel 24 is a straight structure. The width and length of the upper and lower branch channels 24 are greater than those of the middle branch channel 24, ensuring consistent flow resistance across the three branch channels 24. This design not only improves the stress balance of the three cantilever beams 29 but also provides ample reserved space 31 for symmetrical arrangement of the three cantilever beams 29.

[0040] Other quantities can also be set.

[0041] In addition, this application proposes a micropump, such as Figures 4 to 11 As shown, including the pump chamber structure described above, the one-way valve includes a valve body 25 and a support structure 26. The valve body 25 is installed in the inlet channel 17 or outlet channel 20 of the micropump through the support structure 26.

[0042] As one implementation method of this embodiment, such as Figure 4 As shown, the support structure 26 is an annular connecting part 27, and the annular connecting part 27 is provided with a through hole 28. In this embodiment, a cantilever beam 29 is not used. On the one hand, this avoids the stress concentration problem at the connection between the cantilever beam 29 and the valve body 25, making the overall stress on the valve body 25 more uniform, significantly improving the structural stability and service life of the check valve, and reducing the risk of breakage and deformation. On the other hand, the check valve has an overall circular structure, which is much easier to manufacture than the traditional cantilever beam 29 structure. High-precision micromachining of the cantilever beam 29 is unnecessary; only circular hole etching is required on the surface of the circular valve body 25. This simplifies the manufacturing process, effectively shortens the production cycle, and reduces manufacturing costs. The circular check valve is compatible with most fluid channel interfaces and can be widely used in different types of fluid control systems, offering a wide range of applications.

[0043] Furthermore, the dimensions of the through hole 28 on the annular connecting part 27 can be modified and adjusted. For example... Figure 5 As shown, for example, by reducing the size of the through hole 28 and increasing the number of through holes 28, the space inside the through hole 28 and the transition area between the through hole 28 and the adjacent flow channel can be reduced without affecting the unidirectional flow function of the fluid, thus ensuring uniform and stable liquid flow.

[0044] As one implementation method of this embodiment, such as Figures 6 to 11 As shown, the support structure 26 is a cantilever beam 29, and further, there are multiple cantilever beams 29.

[0045] Furthermore, such as Figure 7 and Figure 8As shown, reinforcing ribs 30 are provided between adjacent cantilever beams 29 to form an octagonal shape for the entire support structure 26. In this design, the reinforcing ribs 30 can evenly distribute the fluid pressure and forces during the opening and closing process borne by the cantilever beams 29 to the valve body 25, preventing stress concentration at the connection between the cantilever beams 29 and the valve body 25. This significantly improves the stability of the connection between the cantilever beams 29 and the valve body 25, thereby enhancing the overall structural stability of the check valve and extending its service life. The octagonal structure of the check valve itself possesses good mechanical properties. Combined with the supporting effect of the reinforcing ribs 30, the overall structural strength of the check valve is greatly improved, enabling it to withstand greater fluid pressure impacts and expanding its application range. While ensuring structural stability, the cantilever beams 29 can still open and close flexibly, ensuring the reliability of the one-way fluid flow function and preventing the core working performance of the check valve from being affected by structural improvements.

[0046] Furthermore, such as Figure 7 As shown, the stiffeners 30 between adjacent cantilever beams 29 are single; or as... Figure 8 As shown, there are multiple reinforcing ribs 30 between adjacent cantilever beams 29. The greater number and higher density of reinforcing ribs 30 can more effectively disperse the stress at the connection between the cantilever beam 29 and the valve body 25, further enhancing the stability of the overall structure of the valve body 25, allowing it to withstand a wider range of fluid pressures and making it suitable for harsher working environments.

[0047] Furthermore, such as Figure 7 As shown, the reinforcing rib 30 is straight; or as... Figure 8 As shown, the reinforcing rib 30 is arc-shaped.

[0048] Furthermore, the cantilever beam 29 on the valve body 25 is one or more combinations of straight, broken, bifurcated and curved shapes.

[0049] Furthermore, a clearance groove 32 is provided at the connection between the silicon wafer of the micropump and the cantilever beam 29, and the clearance groove 32 is located below the cantilever beam 29. The clearance groove 32 at the bottom of the cantilever beam 29 can break the adhesion force between the cantilever beam 29 and the surface of the valve body 25, effectively avoiding the adhesion effect that may occur during the opening and closing of the one-way valve, ensuring that the cantilever beam 29 can open and close flexibly and reliably, and improving the working reliability of the one-way valve.

[0050] Furthermore, such as Figure 6 As shown, the size of the clearance groove 32 of the cantilever beam 29 can be reduced. By reducing the depth and / or width of the clearance groove 32, the dead volume of the check valve will not be significantly increased, thus avoiding the problem of decreased fluid transmission efficiency due to structural improvement. While solving the adhesion effect and simplifying the process, the core performance of the check valve is guaranteed.

[0051] For those skilled in the art, various modifications and improvements can be made without departing from the inventive concept of this utility model, and these modifications and improvements all fall within the protection scope of this utility model.

Claims

1. A pump chamber structure, characterized in that, It includes a cavity (23) and a branch channel (24), one end of which is connected to the cavity (23), and the other end of which is used to connect a one-way valve; The number of the branch channels (24) is multiple, and the other ends of the multiple branch channels (24) are uniformly distributed in a circular array with the axis of the one-way valve as the reference.

2. The pump chamber structure according to claim 1, characterized in that, The number of the tributary channels (24) is two or three.

3. A micropump, characterized in that, Including the pump chamber structure as described in claim 1 or 2, the one-way valve includes a valve body (25) and a support structure (26), the valve body (25) being installed in the inlet channel (17) or outlet channel (20) of the micropump via the support structure (26).

4. The micropump according to claim 3, characterized in that, The support structure (26) is an annular connecting part (27), and the annular connecting part (27) is provided with a through hole (28).

5. The micropump according to claim 3, characterized in that, The supporting structure (26) is a cantilever beam (29).

6. The micropump according to claim 5, characterized in that, The number of cantilever beams (29) is multiple.

7. The micropump according to claim 6, characterized in that, A reinforcing bar (30) is provided between adjacent cantilever beams (29).

8. The micropump according to claim 7, characterized in that, The reinforcing bars (30) between adjacent cantilever beams (29) can be single or multiple.

9. The micropump according to claim 7, characterized in that, The reinforcing rib (30) is either straight or curved.

10. The micropump according to claim 5, characterized in that, The cantilever beam (29) on the valve body (25) is one or more combinations of straight, broken, bifurcated and curved shapes.

11. The micropump according to claim 5, characterized in that, The connection between the silicon wafer of the micropump and the cantilever beam (29) is provided with a relief groove (32), which is located below the cantilever beam (29).

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