Direction-controllable micro-droplet generation chip
By designing a micro droplet generation chip with controllable directions, using inverted trapezoidal structure and piezoelectric devices, the problem of relying on external mechanical equipment and cumbersome operations in the prior art is solved, and the efficient micro droplet generation of various liquids is achieved and Convenient splicing and wide application scope.
Patent Information
- Application Number
- CN202411822268.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-11
- Publication Date
- 2025-02-18
AI Technical Summary
The prior art has problems in the generation of micro droplets, such as relying on external mechanical equipment, complicated operation or poor liquid adaptability, and it is difficult to meet the precise operation needs of liquids of various properties.
A micro droplet generation chip with controllable direction is designed, using an inverted trapezoidal structure of fluid inlet and fluid outlet channel, combining piezoelectric devices and pressure chambers to achieve the generation of micro droplets without external mechanical equipment, and through splicing The grooves and raised designs facilitate multi-chip splicing.
It realizes the generation of micro droplets for liquids of various properties such as water-based and oil-based. It is simple to operate and has a wide range of applications. It can independently generate directional pressure to complete fluid supply and micro droplet generation, reducing costs.
Smart Images
Figure CN119456066A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a microfluidic technology, in particular to a direction-controllable micro-droplet generation chip. Background Art
[0002] At present, there is a wide demand for precise manipulation of trace liquids in the fields of chemistry, biology, environmental testing, medical clinical testing, food, pharmaceuticals, micro-nano material research and development, micro-nano structure molding, etc. Precise division of liquids to generate microdroplets is a key technology in the manipulation of trace liquids, and it is also a difficult problem that needs to be solved in the field.
[0003] In recent years, various methods for generating micro-droplets have been disclosed in domestic and foreign literature, including spray emulsification, membrane emulsification, microfluidic chip, spit injection and jetting methods, etc. Among them, CN113996354B discloses a device for controlling the generation of micro-droplets, a generation method and a use thereof, wherein the device comprises a pressure balancing module and a piezoelectric nozzle connected by a micro-liquid pipeline, wherein the piezoelectric nozzle comprises a capillary and a piezoelectric ceramic disposed in a peripheral area of the capillary, the piezoelectric ceramic is electrically connected to a power supply module, and the pressure balancing module is used to inject liquid into the capillary and maintain the liquid in the capillary without flowing out. This technology is based on the different deformation states of piezoelectric ceramics driven by different voltages, and controls the periodic extrusion and expansion of the capillary by adjusting the driving voltage peak value of the power supply module and the output waveform of the driving voltage, thereby forming micro-droplets of different sizes.
[0004] CN118634872A discloses a high-precision controllable jet and micro-droplet synchronous generation device, which includes a droplet generator; a constant temperature water bath connected to one end of the water inlet of the droplet generator, the constant temperature water bath is connected to the droplet generator through a precision peristaltic pump; and a high-speed camera for monitoring the droplet generation quality of the device, the high-speed camera is connected to a computer to transmit monitoring images; the device also includes a signal generator and a power amplifier connected to the droplet generator. In addition to providing jets and synchronous generation of droplets, the generation device can also realize the generation of droplets of non-uniform diameters, further broadening the use scenarios of the droplet generator.
[0005] In addition, CN118874569A discloses a multi-volume micro-droplet generation chip, which includes an upper plate, a droplet generation disk and a lower plate; wherein the lower plate is arranged at the bottom of the droplet generation disk, the upper plate is arranged at the top of the droplet generation disk, and an operation port is arranged on the upper plate; an upper conductive layer is arranged on the upper plate, a lower conductive layer is arranged on the lower plate, and a plurality of droplet generation holes are arranged at the inner bottom of the droplet generation disk; when a bias voltage is set between the upper conductive layer and the lower conductive layer, the hydrophobicity at the bottom of the droplet generation hole is less than the hydrophobicity at the top of the droplet generation hole; the apertures of the plurality of droplet generation holes are different. The multi-volume micro-droplet generation chip is used to form a plurality of tiny droplets to meet the needs of research and development experiments in the fields of biology, chemistry, and pharmaceuticals for a plurality of tiny droplets, without relying on external mechanical equipment, and is compact and easy to carry, with high-throughput generation capability.
[0006] Although the above-mentioned prior arts can all be used to form micro-droplets, the above-mentioned prior arts all have the problems of either relying on external mechanical equipment, complicated operation or poor liquid adaptability. Summary of the invention
[0007] The purpose of the present invention is to provide a direction-controllable micro-droplet generation chip, which does not need to rely on external mechanical equipment; and can be applied to the generation of micro-droplets of liquids of various properties such as water-based and oily liquids, and has a wide range of applications. In addition, the special structure of the micro-droplet generation chip also allows chips to be spliced on demand to meet different needs in different application scenarios and save unnecessary costs.
[0008] To achieve the above object, the present invention adopts the following technical solutions: A direction-controllable micro-droplet generation chip comprises a chip body, a pressure chamber is formed inside the chip body, a piezoelectric device is arranged on one side wall of the pressure chamber; a fluid inlet channel and a fluid outlet channel connected to a cavity inside the pressure chamber are respectively formed at the upper and lower ends of the pressure chamber; wherein the fluid inlet channel and the fluid outlet channel are both inverted trapezoidal structures.
[0009] Furthermore: the fluid inlet channel is connected to an external fluid source through a fluid pipeline, and the cross-sectional area of the first fluid inlet far away from the pressure chamber is larger than the cross-sectional area of the first fluid outlet directly connected to the pressure chamber.
[0010] Furthermore, the cross-sectional area of the second fluid inlet of the fluid outlet channel directly connected to the pressure chamber is larger than the cross-sectional area of the second fluid outlet away from the pressure chamber.
[0011] Preferably, the second fluid outlet is flush with the bottom end of the chip body, and the second fluid outlet is circular.
[0012] More preferably, the first fluid inlet is formed into a square with a size of (0.2mm-10mm)×(0.1mm-2mm), the first fluid outlet is formed into a square with a size of (0.001mm-2mm)×(0.1mm-2mm); the second fluid inlet is formed into a square with a size of (0.2mm-10mm)×(0.1mm-2mm), and the inner diameter of the second fluid outlet is 0.001mm-1mm.
[0013] Furthermore, the cross-sectional area of the first fluid outlet of the fluid inlet channel is smaller than the cross-sectional area of the second fluid inlet of the fluid outlet channel.
[0014] Furthermore: the cross-sectional area of the first fluid outlet of the fluid inlet channel is greater than or equal to the cross-sectional area of the second fluid outlet of the fluid outlet channel.
[0015] According to another embodiment of the present invention, a splicing groove and a splicing protrusion matched with the splicing groove are respectively formed on two opposite sides of the chip body.
[0016] According to a preferred embodiment of the present invention, the pressure chamber is a square with a volume size of (0.5mm-35mm)×(0.2mm-10mm)×(0.1mm-2mm) or a column with an inner diameter of 0.5mm-35mm and a depth of 0.1mm-2mm; the length of the piezoelectric device is 0.1mm-30mm.
[0017] Preferably, the chip body is a metal plate or a metal block.
[0018] The micro-droplet generation chip of the present invention has a simple structure and is easy to operate. Through the design of the fluid inlet channel and the fluid outlet channel with an inverted trapezoidal cross section, the flow direction of the fluid is always controlled to flow out of the fluid inlet channel and out of the fluid outlet channel through the second fluid outlet to form micro-droplets. No additional pump is required to provide pressure for the fluid. It can generate directional pressure and complete fluid replenishment and micro-droplet generation by itself. In addition, the micro-droplet generation chip of the present invention can also be used by splicing multiple micro-droplet generation chips through the design of splicing grooves and splicing protrusions to form a compact micro-droplet generation chip structure. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 The schematic diagram of the structure of the direction-controllable micro-droplet generation chip of the present invention is shown; Figure 2 A schematic diagram showing the micro-droplet formation process of the direction-controllable micro-droplet generation chip of the present invention when power is turned on; Figure 3A schematic diagram showing the micro-droplet formation process of the direction-controllable micro-droplet generation chip of the present invention when the power is off; Figure 4 A schematic diagram showing the micro-droplet formation process of the direction-controllable micro-droplet generation chip of the present invention when power is turned on again; Figure 5 A schematic diagram showing six direction-controllable micro-droplet generation chips of the present invention are spliced together; Figure 6 A photograph of the oily microdroplets obtained in Example 1 of the present invention is shown; Figure 7 A photograph of aqueous microdroplets obtained in Example 2 of the present invention is shown. DETAILED DESCRIPTION
[0020] The present invention provides a direction-controllable micro-droplet generation chip, such as Figure 1 As shown, the micro-droplet generation chip includes a chip body 1, and the chip body 1 can be formed of a metal plate or a metal block, such as a stainless steel plate. The interior of the chip body 1 can be formed with a pressure chamber 11 having a cavity 111 by etching, laser, CNC lathe, etc., and the pressure chamber 11 preferably has a volume size (length×width×depth) of (0.5mm-35mm)×(0.2mm-10mm)×(0.1mm-2mm) of a square or a columnar shape with an inner diameter of 0.5mm-35mm and a depth of 0.1mm-2mm; a piezoelectric device 12 with a length of preferably 0.1mm-30mm is arranged at a longitudinal side wall of the pressure chamber 11, and the piezoelectric device 12 is connected to an external power source through corresponding wiring so that it can be deformed when a voltage is applied, and the piezoelectric device 12 can adopt any structure or shape known in the art, as long as it can be deformed when a voltage is applied.
[0021] The micro-droplet generation chip also includes a fluid inlet channel 13 and a fluid outlet channel 14, which are respectively located at the upper and lower ends of the pressure chamber 11 and are connected to the interior of the cavity 111 of the pressure chamber 11. In the present invention, the fluid inlet channel 13 and the fluid outlet channel 14 both adopt an inverted trapezoidal structure, that is, for the fluid inlet channel 13, it can be connected to the corresponding fluid source 3 through the corresponding fluid pipeline 2, and the cross-sectional area of the first fluid inlet 131 away from the pressure chamber 11 is larger than the cross-sectional area of the first fluid outlet 132 directly connected to the pressure chamber 11. Specifically, the first fluid inlet 131 is preferably formed into a square, and its size is (0.2mm-10mm)×(0.1mm-2mm), and the first fluid outlet 132 is preferably formed into a size of (0.001mm-2mm)×(0.1mm-2mm ), and the depth of the fluid inlet channel 13 is preferably 0.1mm-2mm; and for the fluid outlet channel 14, the cross-sectional area of the second fluid inlet 141 directly connected to the pressure chamber 11 is larger than the cross-sectional area of the second fluid outlet 142 away from the pressure chamber 11 and preferably flush with the bottom end of the chip body 1; specifically, the second fluid inlet 141 is preferably formed into a square with a size of (0.2mm-10mm)×(0.1mm-2mm), and the second fluid outlet 142 is preferably formed into a circle with an inner diameter of 0.001mm-1mm, and the depth of the fluid outlet channel 14 is preferably 0.1mm-2mm. Further, the cross-sectional area of the first fluid outlet 132 of the fluid inlet channel 13 is smaller than the cross-sectional area of the second fluid inlet 141 of the fluid outlet channel 14, and the cross-sectional area of the first fluid outlet 132 of the fluid inlet channel 13 is greater than or equal to the cross-sectional area of the second fluid outlet 142 of the fluid outlet channel 14. By adjusting the corresponding sizes of the fluid inlet and the fluid outlet, the size of the micro-droplets sprayed through the second fluid outlet 142 can be achieved.
[0022] In addition, in actual use, in order to facilitate the generation of multiple micro-droplets, multiple micro-droplet generation chips can be used simultaneously. To this end, a splicing groove 15 can be formed on one side of the chip body 1 of the micro-droplet generation chip of the present invention by, for example, grinding, and a splicing protrusion 16 is correspondingly formed on the other side opposite to the side. Therefore, when it is necessary to use multiple micro-droplet generation chips at the same time, the multiple micro-droplet generation chips are spliced together by the splicing action between the splicing groove 15 and the splicing protrusion 16 to form a compact micro-droplet generation chip structure, such as Figure 5 As shown, the micro-droplet generation chip structure is composed of 6 micro-droplet generation chips spliced together.
[0023] Figure 2-Figure 4FIG. 2 shows the formation process of micro-droplets during the use of the micro-droplet generation chip of the present invention. First, as shown in FIG. Figure 2 As shown, when the piezoelectric device 12 is powered on, it is deformed under pressure and squeezes the fluid in the cavity 111. At this time, the inside of the pressure chamber 11 is under positive pressure, and due to the existence of the positive pressure, the fluid in the cavity 111 flows to the fluid inlet channel 13 and the fluid outlet channel 14 as shown by the arrows. However, since the cross-sectional area of the first fluid outlet 132 of the fluid inlet channel 13 is smaller than the cross-sectional area of the second fluid inlet 141 of the fluid outlet channel 14, the fluid in the fluid outlet channel 14 will be subjected to a greater pressure and flow rate, thereby causing part of the fluid to be ejected through the second fluid outlet 142 of the fluid outlet channel 14 to form microdroplets 4.
[0024] When the power is disconnected, Figure 3 As shown, the piezoelectric device 12 recovers its deformation, and during the process of stretching and straightening, the volume of the pressure chamber 11 gradually increases and becomes a negative pressure. At the same time, due to the existence of the negative pressure, the fluid is returned to the pressure chamber 11 from the fluid inlet channel 13 and the fluid outlet channel 14. However, since the first fluid outlet 132 of the fluid inlet channel 13 is directly connected to the pressure chamber 11, and the second fluid outlet 142 of the fluid outlet channel 14 is far away from the pressure chamber 11, the first fluid outlet 132 of the fluid inlet channel 13 is subjected to a greater negative pressure and fluid reflux, and the fluid flows back through the first fluid outlet 132 and will fill the pressure chamber 11.
[0025] When the power is turned on again, the piezoelectric device 12 will deform again, and the micro-droplet generation chip will undergo the micro-droplet formation process as described above again, and form a second micro-droplet 42 immediately after the first micro-droplet 41. Figure 4 As shown. Through the above-mentioned reciprocating operation of power on and off, the micro-droplet generation chip of the present invention finally realizes the continuous generation of micro-droplets. Due to the inverted trapezoidal structure design of the fluid inlet channel 13 and the fluid outlet channel 14, the flow direction of the fluid is always controlled to flow from upstream to downstream, that is, the fluid always flows from the fluid inlet channel 13 to the fluid outlet channel 14 to form micro-droplets. In addition, since the inverted trapezoidal structure of the fluid inlet channel 13 and the fluid outlet channel 14 can effectively control the flow direction of the fluid, it is no longer necessary to use additional peristaltic pumps, plunger pumps or air pressure pumps and other complex equipment to provide pressure for the fluid. Therefore, the micro-droplet generation chip of the present invention can generate directional pressure by itself and complete fluid replenishment and the generation of micro-droplets.
[0026] Example 1 Six pieces of the micro-droplet generation chips of the present invention as described above are spliced together through the splicing grooves 15 and the splicing protrusions 16 to form a micro-droplet generation chip as shown in FIG. Figure 5The compact micro-droplet generation structure shown in the figure, wherein, for each micro-droplet generation chip, the chip body 1 is made of 304 stainless steel, the length of its piezoelectric device 12 is 1mm, and it is powered by 12V voltage; the size of the pressure chamber 11 is 3mm×2mm×1mm; the size of the first fluid inlet 131 of the fluid inlet channel 13 is 1.5mm×1mm, and the size of its first fluid outlet 132 is 0.15mm×1mm; the size of the second fluid inlet 141 of the outflow outlet channel 14 is 2.8mm×1mm, and its second fluid outlet 142 is a circle with an inner diameter of 0.15mm; the fluid source 3 is an isoparaffin oily liquid, which enters the pressure chamber 11 through the fluid inlet channel 13 via the fluid pipeline 2 and is sprayed out through the second outlet 142 of the fluid outlet channel 14 to form oily micro-droplets, as shown in FIG. Figure 6 As shown, the diameter of the formed oily microdroplets is about 200 μm.
[0027] Example 2 Six pieces of the micro-droplet generation chips of the present invention as described above are spliced together through the splicing grooves 15 and the splicing protrusions 16 to form a micro-droplet generation chip as shown in FIG. Figure 5 The compact micro-droplet generation structure shown in the figure, wherein for each micro-droplet generation chip, the chip body 1 is made of nickel-titanium alloy material, the length of its piezoelectric device 12 is 0.3mm, and it is powered by 5V voltage; the size of the pressure chamber 11 is 1mm×0.5mm×0.3mm; the size of the first fluid inlet 131 of the fluid inlet channel 13 is 0.4mm×0.3mm, and the size of the first fluid outlet 132 is 0.06mm×0.3mm; the size of the second fluid inlet 141 of the fluid outlet channel 14 is 0.3mm×0.3mm, and the second fluid outlet 142 is a circle with a diameter of 0.05mm; the fluid source 3 is pure water, which enters the pressure chamber 11 through the fluid inlet channel 13 via the fluid pipeline 2 and is sprayed out through the second outlet 142 of the fluid outlet channel 14 to form aqueous micro-droplets. For the convenience of observation, 0.1wt% of carmine dye is added to the pure water, as shown in FIG. Figure 7 As shown, the diameter of the formed aqueous microdroplets is about 70 μm.
[0028] The present invention has been described in detail through preferred embodiments. However, through the study of the foregoing, changes and additions to the various embodiments are also obvious to those of ordinary skill in the art. The applicant intends that all these changes and additions fall within the scope of protection of the claims of the present invention. The terms used herein are only for illustration of specific embodiments and are not intended to limit the present invention. Unless otherwise defined, all terms (including technical terms and scientific terms) used herein are the same as those understood by those of ordinary skill in the art to which the present invention belongs. Any modification and improvement of this product, and the replacement and use of similar or similar substances within the scope or category of the patent, are all within the scope of protection of the present invention.
Claims
1. A direction-controllable micro-droplet generation chip, comprising a chip body, characterized in that: A pressure chamber is formed inside the chip body, and a piezoelectric device is arranged on one side wall of the pressure chamber; a fluid inlet channel and a fluid outlet channel connected to the cavity inside the pressure chamber are respectively formed at the upper and lower ends of the pressure chamber; wherein the fluid inlet channel and the fluid outlet channel are both inverted trapezoidal structures.
2. The direction-controllable micro-droplet generation chip according to claim 1, characterized in that: The fluid inlet channel is connected to an external fluid source through a fluid pipeline, and the cross-sectional area of the first fluid inlet far away from the pressure chamber is larger than the cross-sectional area of the first fluid outlet directly connected to the pressure chamber.
3. The direction-controllable micro-droplet generation chip according to claim 2, characterized in that: The cross-sectional area of the second fluid inlet of the fluid outlet channel directly connected to the pressure chamber is larger than the cross-sectional area of the second fluid outlet far from the pressure chamber.
4. The direction-controllable micro-droplet generation chip according to claim 3, characterized in that: The second fluid outlet is flush with the bottom end of the chip body, and the second fluid outlet is circular.
5. The direction-controllable micro-droplet generation chip according to claim 4, characterized in that: The first fluid inlet is formed into a square with a size of (0.2mm-10mm)×(0.1mm-2mm), and the first fluid outlet is formed into a square with a size of (0.001mm-2mm)×(0.1mm-2mm); the second fluid inlet is formed into a square with a size of (0.2mm-10mm)×(0.1mm-2mm), and the inner diameter of the second fluid outlet is 0.001mm-1mm.
6. The direction-controllable micro-droplet generation chip according to claim 3, characterized in that: The cross-sectional area of the first fluid outlet of the fluid inlet channel is smaller than the cross-sectional area of the second fluid inlet of the fluid outlet channel.
7. The direction-controllable micro-droplet generation chip according to claim 3, characterized in that: The cross-sectional area of the first fluid outlet of the fluid inlet channel is greater than or equal to the cross-sectional area of the second fluid outlet of the fluid outlet channel.
8. The direction-controllable micro-droplet generation chip according to any one of claims 1 to 7, characterized in that: Two opposite sides of the chip body are respectively formed with a splicing groove and a splicing protrusion matched with the splicing groove.
9. The direction-controllable micro-droplet generation chip according to any one of claims 1 to 7, characterized in that: The pressure chamber is a square with a volume size of (0.5mm-35mm)×(0.2mm-10mm)×(0.1mm-2mm) or a column with an inner diameter of 0.5mm-35mm and a depth of 0.1mm-2mm; the length of the piezoelectric device is 0.1mm-30mm.
10. The direction-controllable micro-droplet generation chip according to any one of claims 1 to 7, characterized in that: The chip body is a metal plate or a metal block.