Microfluidic chip ultrasonic welding device and welding method

Abstract

The application provides a micro-fluidic chip ultrasonic welding device and a welding method. The micro-fluidic chip ultrasonic welding device comprises a welding platform, an ultrasonic welding assembly arranged in the upper region of the welding platform, a welding base arranged on the top surface of the welding platform, and an elastic film fixedly connected to the top surface of the welding base at the outer periphery edge, so as to form a pressure fluid chamber between the elastic film and the welding base, and the pressure fluid chamber is controllably communicated with a pressure fluid supply component. The elastic film is deformed under the action of the pressure fluid, so that the micro-fluidic chip placed thereon and formed with an upper limit by a welding head is uniformly and fully extruded from the bottom, the pressure of each part of the micro-fluidic chip is equal, and the problem that the welding effect is good in some positions and the welding effect is poor in some positions caused by the thickness deviation of the cover plate and the base plate and the fact that the upper cover plate and the bottom plate of the clamp cannot be completely parallel is effectively solved.

Description

Technical Field

[0001] This invention belongs to the field of microfluidic chip manufacturing technology, specifically relating to an ultrasonic welding device and welding method for microfluidic chips. Background Technology

[0002] In the research on the molding of polymer microfluidic chips, the bonding (i.e., welding) of the substrate and cover plate is an important research direction and a key process in chip manufacturing. Microfluidic chip substrates contain numerous micropits, with sizes ranging from tens to hundreds of micrometers, as well as many tiny flow channels. Even slight damage can affect detection results. Therefore, the quality of chip bonding directly impacts the chip's detection performance. Currently, a common bonding method for microfluidic chips is ultrasonic welding. Ultrasonic welding has different welding modes, using vibration to weld the chip. However, due to variations in chip thickness and inconsistent weld line height and strength during the molding process, leakage may occur in some areas after liquid injection following chip bonding, resulting in an unsightly appearance. Summary of the Invention

[0003] This invention provides a microfluidic chip ultrasonic welding device and welding method, which can solve the technical problem in the prior art of inconsistent pressure caused by unevenness in the welding lines of the microfluidic substrate and cover plate, resulting in inconsistent strength of the chip welding lines.

[0004] To address the above problems, the present invention provides a microfluidic chip ultrasonic welding device, comprising:

[0005] A welding platform, with ultrasonic welding components installed in its upper area;

[0006] A welding base is placed on the top surface of the welding platform;

[0007] An elastic membrane, the outer periphery of which is fixedly connected to the top surface of the welding base, forms a pressure fluid chamber between the elastic membrane and the welding base, and the pressure fluid chamber is controllably connected to a pressure fluid supply component.

[0008] In some embodiments, a sealing connecting ring is also included, which is connected to the welding base, and the sealing connecting ring is stacked on the outer peripheral edge region of the elastic membrane to achieve the clamping of the elastic membrane by the sealing connecting ring and the welding base.

[0009] In some embodiments, the sealing connecting ring and the welding base have an uneven structure, and the elastic membrane is held in the uneven structure.

[0010] In some embodiments, a first positioning blind hole is formed on the top surface of the welding base, and a first positioning post is formed on the bottom side surface of the elastic membrane. The first positioning post is inserted into the first positioning blind hole, and the free end of the first positioning post is still in the first positioning blind hole when the elastic membrane undergoes maximum elastic deformation under the action of the pressure fluid.

[0011] In some embodiments, a second positioning blind hole is formed on the top surface of the elastic membrane, and the second positioning blind hole is coaxially arranged with the first positioning post. The bottom side surface of the substrate of the microfluidic chip has a second positioning post that is matched and inserted into the second positioning blind hole.

[0012] In some embodiments, the welding base is provided with a fluid supply channel having a channel outlet communicating with the pressure fluid chamber and a channel inlet communicating with the outlet of the pressure fluid supply component.

[0013] The present invention also provides a method for ultrasonic welding of microfluidic chips, which is performed using the above-mentioned ultrasonic welding device for microfluidic chips, and includes the following steps:

[0014] The substrate and cover plate of the microfluidic chip are stacked sequentially on the top surface of the elastic membrane and correspond to the position of the welding head of the ultrasonic welding assembly;

[0015] The ultrasonic welding assembly is controlled to descend so that the welding head contacts the top surface of the cover plate;

[0016] Control the operation of the pressure fluid supply component to supply pressure fluid at the target pressure to the pressure fluid chamber;

[0017] The ultrasonic welding assembly is controlled to perform ultrasonic welding on the welding areas of the substrate and cover plate.

[0018] In some embodiments, when a second positioning post is provided on the bottom surface of the substrate, the ultrasonic welding method further includes:

[0019] Insert each of the second positioning pins into the second positioning blind hole.

[0020] In some embodiments, after the cover plate is welded to the substrate, the microfluidic chip is removed and the second positioning post is cut off.

[0021] The ultrasonic welding device and welding method for microfluidic chips provided by this invention have the following beneficial effects:

[0022] The pressure fluid supply component delivers a pressure fluid (gas, liquid, etc.) with a target pressure into the pressure fluid chamber. The elastic membrane deforms under the action of the pressure fluid, thereby creating a uniform and comprehensive compression of the microfluidic chip placed on it and limited at the top by the welding head. This ensures that the pressure is equal at all points on the microfluidic chip, effectively solving the problem of good welding results in some positions and poor welding results in others due to thickness deviations between the cover plate and the substrate, and the inability of the cover plate and the bottom plate on the fixture to be completely parallel. Attached Figure Description

[0023] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0024] The structures, proportions, sizes, etc. illustrated in this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0025] Figure 1 This is a three-dimensional structural schematic diagram of the ultrasonic welding device for microfluidic chips according to an embodiment of the present invention;

[0026] Figure 2 for Figure 1 Exploded view of some components;

[0027] Figure 3 for Figure 2 A schematic diagram of the welding base in the diagram;

[0028] Figure 4 for Figure 2 A schematic diagram of the elastic membrane in the diagram;

[0029] Figure 5 for Figure 2 A schematic diagram of the sealing connection ring in the middle;

[0030] Figure 6 for Figure 2 Schematic diagram of the substrate structure;

[0031] Figure 7 A schematic diagram of the structure of the component supplying pressure fluid.

[0032] The reference numerals in the attached figures are as follows:

[0033] 1. Transducer; 2. Amplifier; 3. Welding head; 4. Welding platform; 5. Cover plate; 6. Substrate; 7. Sealing ring; 8. Elastic membrane; 9. Welding base; 10. First positioning blind hole; 12. Flow channel outlet; 13. Flow channel inlet; 14. Second positioning blind hole; 16. Threaded hole; 17. Second positioning post; 19. Pressure fluid supply component; 20. Base threaded hole. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0036] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0037] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0038] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0039] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0040] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0041] See Figures 1 to 7As shown, according to an embodiment of the present invention, a microfluidic chip ultrasonic welding apparatus is provided, comprising:

[0042] Welding platform 4 serves as the mounting carrier for its upper components. Specifically, an ultrasonic welding assembly is installed in the upper area of ​​the welding platform 4. This ultrasonic welding assembly is vertically and vertically mounted in the upper area of ​​the welding platform 4 via corresponding lifting columns. As is known in the industry, the ultrasonic welding assembly includes a transducer 1 and an amplitude transformer 2 connected to it. The transducer 1 converts electrical energy into mechanical energy to realize the vibration of the amplitude transformer 2. The amplitude transformer 2 is connected to a welding head 3. The amplitude transformer 2 changes the amplitude of the welding head 3 by increasing or decreasing the amplitude, thereby realizing ultrasonic welding of the microfluidic chip that is in contact with it through the welding head 3.

[0043] A welding base 9 is placed on the top surface of the welding platform 4, and a base threaded hole 20 is constructed thereon, through which the base threaded hole 20 is bolted to the welding platform 4;

[0044] An elastic membrane 8 is fixedly connected to the top surface of the welding base 9 at its outer peripheral edge to form a pressure fluid chamber (not indicated in the figure) between the elastic membrane 8 and the welding base 9. The pressure fluid chamber is controllably connected to the pressure fluid supply component 19.

[0045] In this technical solution, the pressure fluid supply component 19 delivers a pressure fluid (gas, liquid, etc.) with a target pressure into the pressure fluid chamber. The elastic membrane 8 deforms under the action of the pressure fluid, thereby forming a uniform and comprehensive compression of the microfluidic chip placed on it and limited at the top by the welding head 3. This ensures that the pressure is equal at all parts of the microfluidic chip, effectively solving the problem that the welding effect is good in some places and poor in others due to the thickness deviation between the cover plate and the substrate, and the inability of the cover plate and the bottom plate on the fixture to be completely parallel.

[0046] The aforementioned pressure fluid supply component 19, as shown Figure 7 As shown, commercially available water pumps or air pumps can be used.

[0047] In some implementations, see Figure 1 and Figure 2As shown, it also includes a sealing connecting ring 7, which is connected to the welding base 9, and the sealing connecting ring 7 is stacked on the outer peripheral edge region of the elastic membrane 8 to achieve clamping of the elastic membrane 8 by the sealing connecting ring 7 and the welding base 9. Specifically, the aforementioned sealing connecting ring 7 is constructed with threaded holes 16, which form a threaded connection with the welding base 9 through these threaded holes 16. Since the sealing connecting ring 7 and the elastic membrane 8 are stacked, the fixed-position sealing connecting ring 7 and the welding base 9 together form a clamping of the elastic membrane 8, thereby improving assembly efficiency. Furthermore, the aforementioned sealing connecting ring 7 has a concave-convex structure between the side wall of the welding base 9 facing the welding base 9 and the side wall of the welding base 9 facing the sealing connecting ring 7, and the elastic membrane 8 is clamped in the concave-convex structure. This concave-convex structure can ensure reliable clamping of the edge of the elastic membrane 8 on the one hand, and effectively prevent leakage of pressurized fluid in the pressurized fluid chamber on the other hand. The aforementioned concave-convex structure includes a raised ring and a grooved ring arranged around the outer peripheral edge of the elastic membrane 8, wherein the raised ring and the grooved ring are fitted together.

[0048] See details Figure 3 As shown, in some embodiments, a first positioning blind hole 10 is formed on the top surface of the welding base 9, and a first positioning post (not shown in the figure) is formed on the bottom side surface of the elastic membrane 8. The first positioning post is inserted into the first positioning blind hole 10, and the free end of the first positioning post is still in the first positioning blind hole 10 when the elastic membrane 8 undergoes maximum elastic deformation under the action of the pressure fluid.

[0049] In this technical solution, the first positioning post on the bottom surface of the elastic membrane 8 and the first positioning blind hole 10 on the welding base 9 are inserted and matched to limit and guide the deformation direction of the elastic membrane 8, thereby ensuring that the horizontal position of the elastic membrane 8 and the microfluidic chip is relatively stable, and thus ensuring the stability of the relative position of the cover plate 5 and the substrate 6 during the ultrasonic welding process.

[0050] For details, please refer to [link / reference]. Figure 4 and Figure 6 As shown, a second positioning blind hole 14 is constructed on the top surface of the elastic membrane 8, and the second positioning blind hole 14 is coaxially arranged with the first positioning post. The bottom side surface of the substrate 6 of the microfluidic chip has a second positioning post 17 that is matched and inserted into the second positioning blind hole 14.

[0051] In this technical solution, the second positioning blind hole 14 and the first positioning post are coaxially arranged, which can ensure the deformation guidance of the elastic membrane 8, prevent the relative misalignment of the cover plate 5 and the substrate 6, and at the same time ensure the sealing of the pressure fluid chamber, making the structure more compact.

[0052] It is understandable that the number of the aforementioned first positioning post and second positioning post 17 can both be set to multiple.

[0053] See details Figure 3 As shown, in some embodiments, the welding base 9 is provided with a fluid supply channel (not shown in the figure), which has a channel outlet 12 communicating with the pressure fluid chamber and a channel inlet 13 communicating with the outlet of the pressure fluid supply component 19. Constructing the fluid supply channel within the welding base 9 makes the structural design more compact and rational.

[0054] According to an embodiment of the present invention, an ultrasonic welding method for microfluidic chips is also provided, which is performed using the above-described ultrasonic welding apparatus for microfluidic chips, and includes the following steps:

[0055] The substrate 6 and cover plate 5 of the microfluidic chip are stacked sequentially on the top surface of the elastic membrane 8 and correspond to the position of the welding head 3 of the ultrasonic welding assembly.

[0056] The ultrasonic welding assembly is controlled to descend so that the welding head 3 contacts the top surface of the cover plate 5;

[0057] The pressure fluid supply component 19 is controlled to supply pressure fluid at a target pressure to the pressure fluid chamber.

[0058] The ultrasonic welding assembly is controlled to perform ultrasonic welding on the welding areas of the substrate 6 and the cover plate 5.

[0059] The pressure fluid supply component 19 delivers a pressure fluid (gas, liquid, etc.) with a target pressure into the pressure fluid chamber. The elastic membrane 8 deforms under the action of the pressure fluid, thereby forming a uniform and comprehensive compression on the microfluidic chip placed on it and limited at the top by the welding head 3. This ensures that the pressure is equal at all parts of the microfluidic chip, effectively solving the problem that the welding effect is good in some places and poor in others due to the thickness deviation between the cover plate and the substrate, and the inability of the cover plate and the bottom plate on the fixture to be completely parallel.

[0060] In some embodiments, when the substrate 6 has second positioning posts 17 on its bottom surface, the ultrasonic welding method further includes inserting each of the second positioning posts 17 into a second positioning blind hole 14. This stabilizes the relative position of the substrate 6 and the elastic membrane 8, improving the welding effect.

[0061] After the cover plate 5 and the substrate 6 are welded together, the microfluidic chip is removed, and the second positioning post 17 is cut off. This improves the versatility of the microfluidic chip.

[0062] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention. The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. A microfluidic chip ultrasonic welding device, characterized in that, include: Welding platform (4), with an ultrasonic welding assembly installed in the upper area; The welding base (9) is placed on the top surface of the welding platform (4); An elastic membrane (8) is fixedly connected to the top surface of the welding base (9) at its outer peripheral edge to form a pressure fluid chamber between the elastic membrane (8) and the welding base (9), and the pressure fluid chamber is controllably connected to the pressure fluid supply component (19). The welding base (9) has a first positioning blind hole (10) on its top surface and a first positioning post on the bottom side of the elastic membrane (8). The first positioning post is inserted into the first positioning blind hole (10) and the free end of the first positioning post is still in the first positioning blind hole (10) when the elastic membrane (8) undergoes maximum elastic deformation under the action of pressure fluid. The top surface of the elastic membrane (8) has a second positioning blind hole (14) and the second positioning blind hole (14) is coaxially arranged with the first positioning post. The bottom side of the substrate (6) of the microfluidic chip has a second positioning post (17) that is matched and inserted into the second positioning blind hole (14).

2. The microfluidic chip ultrasonic welding device according to claim 1, characterized in that, It also includes a sealing connecting ring (7), which is connected to the welding base (9), and the sealing connecting ring (7) is stacked on the outer peripheral edge area of ​​the elastic membrane (8) to achieve the clamping of the elastic membrane (8) by the sealing connecting ring (7) and the welding base (9).

3. The ultrasonic welding device for microfluidic chips according to claim 2, characterized in that, The sealing connecting ring (7) and the welding base (9) have a concave-convex structure, and the elastic membrane (8) is held in the concave-convex structure.

4. The ultrasonic welding apparatus for microfluidic chips according to claim 1, characterized in that, The welding base (9) has a fluid supply channel, which has a channel outlet (12) communicating with the pressure fluid chamber and a channel inlet (13) communicating with the outlet of the pressure fluid supply component (19).

5. A method for ultrasonic welding of microfluidic chips, characterized in that, Performed using the microfluidic chip ultrasonic welding apparatus according to any one of claims 1 to 4, the process includes the following steps: The substrate (6) and cover plate (5) of the microfluidic chip are stacked sequentially on the top surface of the elastic membrane (8) and correspond to the position of the welding head (3) of the ultrasonic welding assembly. The ultrasonic welding assembly is controlled to descend so that the welding head (3) abuts against the top surface of the cover plate (5); Control the operation of the pressure fluid supply component (19) to supply pressure fluid at the target pressure to the pressure fluid chamber; The ultrasonic welding assembly is controlled to perform ultrasonic welding on the welding areas of the substrate (6) and cover plate (5).

6. The ultrasonic welding method for microfluidic chips according to claim 5, characterized in that, When the substrate (6) has a second positioning post (17) on its bottom surface, the ultrasonic welding method further includes: Each of the second positioning pins (17) is inserted into the second positioning blind hole (14).

7. The ultrasonic welding method for microfluidic chips according to claim 6, characterized in that, After the cover plate (5) and the substrate (6) are welded together, the microfluidic chip is removed and the second positioning post (17) is cut off.

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