Microfluidic integrated multi-cavity extrusion structure

Abstract

The invention relates to the technical field of micro-fluidic chips, in particular to a micro-fluidic integrated multi-cavity extrusion structure which comprises a main body shell, a first flow channel module, a second flow channel module and a third flow channel module are sequentially embedded in the main body shell from top to bottom, an axially-penetrating central liquid inlet channel is formed in the first flow channel module, and a liquid outlet channel is formed in the second flow channel module. A plurality of lateral liquid inlet channels which are annularly distributed are arranged in the second flow channel module, a converging guide head is fixedly connected to the lower end of the third flow channel module, an inverted-cone-shaped multi-phase converging cavity is formed in the converging guide head, and the lower end of the multi-phase converging cavity is converged to form a micro-scale liquid outlet which is axially led out. According to the microfluidic integrated multi-cavity extrusion structure, multi-phase fluid can be effectively converged and centered before being led out, the initial convergence stability and interface definition of the fluid are improved, and the uniformity of extrusion molding is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of microfluidic chip, in particular to a microfluidic integrated multi-lumen extrusion structure. BACKGROUND

[0002] Microfluidic technology has been widely used in biological detection, drug screening, cell culture and material micro-machining fields due to its high precision, low consumption and high integration in micro fluid control. Among them, the microfluidic extrusion structure as the key component to realize the precise distribution and forming of multi-phase fluid, its design directly affects the uniformity and process stability of the product.

[0003] At present, most microfluidic multi-lumen extrusion devices adopt planar laminated or coaxial nested channel design, and the fluid distribution usually relies on the parallel or concentric leading out through multiple independent micro-holes at the end of the chip. However, when realizing the synchronous extrusion of multiple-phase materials, the outlet ends of each flow channel are often directly exposed to the external environment or receiving substrate. However, this kind of open outlet layout has obvious defects in actual operation: when multiple fluids are extruded and merged at the same outlet area, due to the lack of effective constraint on the initial confluence form, each phase fluid is easily affected by the difference in surface tension and external disturbance at the moment of leaving the outlet, and horizontal diffusion or deviation occurs, resulting in blurred multi-phase interface, uneven extrusion filament diameter, and even component misplacement phenomenon. This problem is particularly significant under high flow rate or low viscosity fluid conditions, which seriously restricts the consistency and precision of complex microstructure forming. SUMMARY

[0004] The purpose of the present application is to provide a microfluidic integrated multi-lumen extrusion structure to solve the problem that the current multi-lumen extrusion structure lacks effective guidance and constraint at the fluid outlet area, leading to horizontal diffusion, deviation and interface mixing of multi-phase fluid at the initial stage of leading out, thereby affecting the uniformity and precision of complex microstructure forming.

[0005] To achieve the above purpose, the present application provides the following technical scheme: a microfluidic integrated multi-lumen extrusion structure, comprising a main body shell, a first flow channel module, a second flow channel module and a third flow channel module are sequentially embedded inside the main body shell from top to bottom, a center liquid inlet channel axially penetrating is arranged in the first flow channel module, a plurality of lateral liquid inlet channels distributed in a ring shape are arranged in the second flow channel module, a converging guide head is fixedly connected to the lower end of the third flow channel module, a multi-phase confluence cavity in an inverted conical shape is arranged inside the converging guide head, and the lower end of the multi-phase confluence cavity is narrowed into a micro-scale liquid outlet axially leading out.

[0006] Preferably, the main body shell is provided with stepped installation cavities matching the outer shapes of the first, second and third flow channel modules, and sealing gaskets are arranged between the first, second and third flow channel modules.

[0007] Preferably, the number of lateral liquid inlet channels is four, which are evenly distributed along the circumferential direction of the second flow channel module, and the upper surface of the third flow channel module is provided with an annular converging groove, the inner ends of the lateral liquid inlet channels are in communication with the annular converging groove, and the annular converging groove extends downward and is in communication with the upper part of the multi-phase converging cavity.

[0008] Preferably, the lower end outlet of the central liquid inlet channel is located at the center of the third flow channel module, the central region of the third flow channel module is provided with a vertically extending central through hole, the upper end of the central through hole is connected with the outlet of the central liquid inlet channel, and the lower end of the central through hole is in communication with the top center of the multi-phase converging cavity.

[0009] Preferably, the lower end of the third flow channel module is provided with an external threaded segment, and the upper end of the converging guide head is provided with a matching internal threaded hole.

[0010] Preferably, the inner wall of the multi-phase converging cavity is a continuous smooth taper with a taper angle of 30°-60°, the upper end opening diameter is 1.0mm-1.5mm, and the lower end opening diameter is 0.3mm-0.6mm.

[0011] Preferably, the micro-scale liquid outlet is a circular through hole with a diameter of 80μm-300μm, and its axis coincides with the central axis of the multi-phase converging cavity.

[0012] Preferably, the converging guide head is made of wear-resistant ceramic material, the outer wall of the converging guide head is provided with a positioning flat key, and the inner wall of the main body shell is provided with an axial key groove matched with the positioning flat key.

[0013] Preferably, the lower end of the converging guide head extends beyond the bottom end surface of the main body shell, and the outer wall of the extended segment of the converging guide head is provided with an anti-rotation flat surface.

[0014] Preferably, the outlet end of the micro-scale liquid outlet is provided with an inwardly tapered annular taper, and the inner surface of the annular taper is a tapered surface which gradually shrinks towards the liquid outlet direction.

[0015] Compared with the prior art, the beneficial effects of the microfluidic integrated multi-lumen extrusion structure are that the multi-phase fluid can be effectively converged and centered before being introduced, the stability of the initial convergence of the fluid and the interface definition are improved, and the uniformity of the extrusion molding is improved. Through the collaborative design of the third flow channel module and the inverted cone-shaped multi-phase convergence cavity in the convergence guide head, the pre-convergence and axial guidance of the multi-phase fluid in the closed cavity are realized, the spatial distribution of the center liquid inlet channel and the lateral liquid inlet channel is combined, and the converging structure of the micro-scale liquid outlet is combined, so that the diffusion and deviation of the fluid at the outlet are effectively suppressed, and the controllability and molding precision of the multi-phase extrusion process are significantly improved. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 Figure 1 is a structural schematic diagram of a microfluidic integrated multi-lumen extrusion structure of the present application;

[0017] Figure 2 Figure 2 is a structural schematic diagram of a first flow channel module of the microfluidic integrated multi-lumen extrusion structure of the present application;

[0018] Figure 3 Figure 3 is a structural schematic diagram of a second flow channel module of the microfluidic integrated multi-lumen extrusion structure of the present application;

[0019] Figure 4 Figure 4 is a structural schematic diagram of a third flow channel module of the microfluidic integrated multi-lumen extrusion structure of the present application;

[0020] Figure 5 Figure 5 is a structural schematic diagram of an external structure of a convergence guide head of the microfluidic integrated multi-lumen extrusion structure of the present application.

[0021] In the figure: 1, main body shell; 2, first flow channel module; 21, center liquid inlet channel; 3, second flow channel module; 31, lateral liquid inlet channel; 4, third flow channel module; 41, annular convergence groove; 42, center through hole; 5, convergence guide head; 51, positioning flat key; 6, multi-phase convergence cavity; 7, micro-scale liquid outlet; 71, annular converging; 8, sealing washer. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the present application.

[0023] Please refer to Figures 1-5The application provides a technical scheme: a micro-fluid integrated multi-lumen extrusion structure, which comprises a main body shell 1, a first flow channel module 2, a second flow channel module 3 and a third flow channel module 4 are sequentially embedded in the main body shell 1 from top to bottom, the first flow channel module 2 is internally provided with a central liquid inlet channel 21 penetrating in the axial direction, the second flow channel module 3 is internally provided with a plurality of lateral liquid inlet channels 31 distributed in a ring shape, the lower end of the third flow channel module 4 is fixedly connected with a converging guide head 5, the converging guide head 5 is internally provided with a multi-phase converging cavity 6 in an inverted conical shape, the lower end of the multi-phase converging cavity 6 is narrowed into a micro-scale liquid outlet 7 leading in the axial direction, multi-phase fluids are synchronously introduced through the central liquid inlet channel 21 of the first flow channel module 2 and the plurality of lateral liquid inlet channels 31 of the second flow channel module 3, the central phase fluid is downwardly conveyed through the central liquid inlet channel 21, the peripheral multi-phase fluid is circumferentially converged through the lateral liquid inlet channels 31, the two are spatially intersected in the connecting area of the third flow channel module 4 and the converging guide head 5, the multi-phase fluid after intersection immediately enters the inverted conical multi-phase converging cavity 6 in the converging guide head 5, the fluid is forced to converge to the central axis under the geometric constraint of the conical surface, dynamic centering and interface integration are realized, then the fluid is axially led out through the micro-scale liquid outlet 7 formed by the lower end of the multi-phase converging cavity 6, the closed inverted conical multi-phase converging cavity 6 is arranged at the front end of the liquid outlet, so that the multi-phase fluid has completed preliminary convergence and stable guidance before leaving the micro-scale liquid outlet 7, the horizontal diffusion and deviation phenomenon caused by the difference in surface tension and external disturbance is effectively inhibited, the clarity of the multi-phase interface and the consistency of the filament diameter in the initial extrusion stage are significantly improved, the problems of disordered fluid convergence, fuzzy interface and uneven forming caused by the open outlet layout in the prior art are solved, the main body shell 1 is internally provided with a stepped mounting cavity matched with the shapes of the first flow channel module 2, the second flow channel module 3 and the third flow channel module 4, and the first flow channel module 2, the second flow channel module 3 and the third flow channel module 4 are all provided with sealing gaskets 8, the stepped mounting cavity in the main body shell 1 is used for realizing the accurate positioning and stable embedding of the first flow channel module 2, the second flow channel module 3 and the third flow channel module 4, the axial centering of the multi-stage flow channel is ensured, and reliable sealing is formed between the modules by the sealing gaskets 8, so that the multi-phase fluid is prevented from leaking in the high-pressure conveying process, the independence and operation stability of the flow channel system are ensured, the number of the lateral liquid inlet channels 31 is four, the lateral liquid inlet channels 31 are uniformly distributed along the circumferential direction of the second flow channel module 3, the upper surface of the third flow channel module 4 is provided with a ring-shaped converging groove 41, the inner ends of the lateral liquid inlet channels 31 are all in communication with the ring-shaped converging groove 41, the ring-shaped converging groove 41 downwardly extends and is in communication with the upper part of the multi-phase converging cavity 6, the communication design of the four circumferentially distributed lateral liquid inlet channels 31 and the ring-shaped converging groove 41 enables the peripheral fluid to be uniformly converged into the third flow channel module 4 and smoothly transferred to the multi-phase converging cavity 6 through the ring-shaped converging groove 41, the deviation and turbulent flow of the fluid in the fluid introduction process are effectively avoided,The uniformity of distribution and the stability of flow of multiphase fluid before merging are improved, the lower end outlet of the central liquid inlet channel 21 is located at the central position of the third flow channel module 4, the center of the second flow channel module 3 is provided with a through hole, the central area of the third flow channel module 4 is provided with a vertically extending central through hole 42, the upper end of the central through hole 42 is connected with the outlet of the central liquid inlet channel 21, and the lower end of the central through hole 42 is in communication with the top center of the multiphase merging cavity 6, the structure connects the outlet of the central liquid inlet channel 21 with the top center of the multiphase merging cavity 6 through the central through hole 42, ensures that the central phase fluid is stably introduced into the merging area along the axial direction, meanwhile, the through hole in the center of the second flow channel module 3 avoids hindering the central flow channel, guarantees the continuity and centration of the central fluid passage, and is beneficial to the symmetric and orderly initial merging of the multiphase fluid in the merging cavity, the lower end of the third flow channel module 4 is provided with an external thread section, and the upper end of the converging guide head 5 is provided with a matching internal thread hole, the structure realizes the firm fixing and axial centration between the external thread section of the third flow channel module 4 and the internal thread hole of the converging guide head 5, ensures the accurate butt joint of the multiphase merging cavity 6 and the flow channel system, is convenient for dismounting and maintaining, improves the assembly precision and use reliability of the structure, the inner wall of the multiphase merging cavity 6 is a continuous and smooth conical surface, the taper angle is 30°-60°, the upper end opening diameter is 1.0mm-1.5mm, and the lower end opening diameter is 0.3mm-0.6mm, the structure of the inner wall of the multiphase merging cavity 6 produces a gradual convergence effect on the merging multiphase fluid, guides the fluid to stably gather around the central axis, effectively reduces the flow resistance and vortex, and simultaneously optimizes the flow field distribution through the cooperation of the taper angle and the stepped diameter change, improves the integration quality and extrusion stability of the multiphase interface, the micro-scale liquid outlet 7 is a circular through hole with a diameter of 80μm-300μm, and the axis thereof is coincident with the central axis of the multiphase merging cavity 6, the structure of the micro-scale liquid outlet 7 ensures that the multiphase fluid maintains axial symmetric flow when being led out, avoids deflection and jet deviation, simultaneously, the micron-level pore diameter cooperates with the pre-merging design, effectively controls the liquid flow and filament diameter, and improves the precision and consistency of microstructure forming, the converging guide head 5 is made of wear-resistant ceramic material, the outer wall thereof is provided with a positioning flat key 51, and the inner wall of the main body shell 1 is provided with an axial key groove matched with the positioning flat key 51, the structure improves the wear resistance and corrosion resistance of the converging guide head 5, prolongs the service life, simultaneously, the circumferential limiting is realized through the cooperation of the positioning flat key 51 and the axial key groove of the inner wall of the main body shell 1, the rotation in the use process is prevented, the centration precision and assembly stability of the flow channel are ensured, the lower end of the converging guide head 5 extends out of the bottom end surface of the main body shell 1, and the outer wall of the extension section of the converging guide head 5 is provided with an anti-rotation flat surface, the lower end of the converging guide head 5 is convenient for being clamped and fixed by using tools when the downstream device is installed or connected, the rotation of the converging guide head 5 in the tightening process is prevented, the reliable thread connection is ensured, the outlet end of the micro-scale liquid outlet 7 is provided with an inwardly closed annular closing 71, the inner surface of the annular closing 71 is a conical surface, the taper angle thereof gradually contracts towards the liquid outlet direction,The annular converging section 71 further enhances the converging effect when the fluid is drawn out, suppresses the diffusion of the fluid at the outlet and the edge disturbance, and improves the stability of the jet. Meanwhile, the tapered converging section helps to form a uniform and continuous extruded filament, and improves the surface quality and size consistency of the microstructure.

[0024] Working principle: When the microfluidic integrated multi-lumen extrusion structure is used, the central phase fluid is first introduced into the central liquid inlet channel 21 of the first flow channel module 2, and the peripheral multi-phase fluid is introduced into the multiple lateral liquid inlet channels 31 of the second flow channel module 3. The fluids flow synchronously under the action of pressure. The central phase fluid passes through the through hole in the center of the second flow channel module 3 through the central liquid inlet channel 21, enters the third flow channel module 4, and intersects with the peripheral fluid introduced by the lateral liquid inlet channel 31 through the annular converging groove 41 at the connection area between the third flow channel module 4 and the converging guide head 5. The multi-phase fluid then enters the multi-phase converging cavity 6 inside the converging guide head 5, and then the fluid is axially extruded through the micro-scale liquid outlet 7 connected to the lower end of the multi-phase converging cavity 6. The annular converging section 71 at the outlet end of the micro-scale liquid outlet 7 further guides the stable drawing of the fluid, thereby completing a series of work.

[0025] Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can modify the technical solutions described in the foregoing embodiments, or make equivalent replacements to some of the technical features, as long as they are within the spirit and principles of the present application. Any modification, equivalent replacement, improvement, etc. made within the scope of the present application shall be included in the protection scope of the present application.

Claims

1. A microfluidic integrated multi-cavity extrusion structure, comprising a main body shell (1), characterized in that: The main body shell (1) is provided with a first flow channel module (2), a second flow channel module (3) and a third flow channel module (4) in sequence from top to bottom. The first flow channel module (2) is provided with an axially penetrating central liquid inlet channel (21), the second flow channel module (3) is provided with a plurality of annularly distributed lateral liquid inlet channels (31), the lower end of the third flow channel module (4) is fixedly connected to a converging guide head (5), the converging guide head (5) is provided with an inverted conical multiphase converging chamber (6), and the lower end of the multiphase converging chamber (6) converges into an axially extending microscale liquid outlet (7).

2. The microfluidic integrated multi-cavity extrusion structure according to claim 1, characterized in that: A stepped installation cavity matching the outer shapes of the first flow channel module (2), the second flow channel module (3) and the third flow channel module (4) is provided in the main body shell (1), and sealing gaskets (8) are provided between the first flow channel module (2), the second flow channel module (3) and the third flow channel module (4).

3. The microfluidic integrated multi-cavity extrusion structure according to claim 1, characterized in that: The number of the lateral liquid inlet channels (31) is four and they are evenly distributed along the circumferential direction of the second flow channel module (3), and the upper surface of the third flow channel module (4) is provided with an annular confluence groove (41), the inner ends of the lateral liquid inlet channels (31) are connected to the annular confluence groove (41), and the annular confluence groove (41) extends downward and is connected to the upper part of the multiphase confluence chamber (6).

4. The microfluidic integrated multi-cavity extrusion structure according to claim 1, characterized in that: The lower end outlet of the central liquid inlet channel (21) is located at the center of the third flow channel module (4), and a vertically extending central conduction hole (42) is provided in the central area of ​​the third flow channel module (4). The upper end of the central conduction hole (42) is connected to the outlet of the central liquid inlet channel (21), and the lower end of the central conduction hole (42) is connected to the top center of the multiphase confluence chamber (6).

5. The microfluidic integrated multi-cavity extrusion structure according to claim 1, characterized in that: The lower end of the third flow channel module (4) is provided with an external thread section, and the upper end of the converging guide head (5) is provided with a matching internal thread hole.

6. The microfluidic integrated multi-cavity extrusion structure according to claim 1, characterized in that: The inner wall of the multiphase confluence cavity (6) is a continuous and smooth conical surface with a cone angle of 30°-60°, an upper opening diameter of 1.0 mm-1.5 mm, and a lower opening diameter of 0.3 mm-0.6 mm.

7. The microfluidic integrated multi-cavity extrusion structure according to claim 1, characterized in that: The microscale liquid outlet (7) is a circular through hole with a diameter of 80 μm-300 μm, and its axis coincides with the central axis of the multiphase confluence cavity (6).

8. The microfluidic integrated multi-cavity extrusion structure according to claim 1, characterized in that: The converging guide head (5) is made of a wear-resistant ceramic material, and a positioning flat key (51) is provided on its outer wall, and an axial key groove matching the positioning flat key (51) is provided on the inner wall of the main body shell (1).

9. The microfluidic integrated multi-cavity extrusion structure according to claim 1, characterized in that: The lower end of the converging guide head (5) extends out of the bottom end surface of the main body shell (1), and the outer wall of the extended section of the converging guide head (5) is provided with an anti-rotation plane.

10. The microfluidic integrated multi-cavity extrusion structure according to claim 1, characterized in that: The outlet end of the micro-scale liquid outlet (7) is provided with an inwardly contracting annular opening (71), and the inner surface of the annular opening (71) is a conical surface, the cone angle of which gradually contracts toward the liquid outlet direction.

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