A microneedle casting system and a microneedle preparation method

Abstract

The present invention discloses a microneedle casting system and a microneedle preparation method, comprising a vacuum chamber, a motion platform, a first motion component, a liquid filling needle component, a second motion component and a controller; the motion platform is arranged in the vacuum chamber; the first motion component comprises a first transmission component and a first driving component connected to each other, the motion platform is connected to the first transmission component, and the first transmission component drives the motion platform to move along a first direction or / and a third direction under the drive of the first driving component; the liquid filling needle component comprises a liquid outlet head and a liquid filling needle rod, one end of the liquid filling needle rod extends into the vacuum chamber and is connected to the liquid outlet head; the second motion component comprises a second transmission component and a second driving component connected to each other, the liquid filling needle is connected to the second transmission component, and the second transmission component drives the liquid filling needle to move along a second direction under the drive of the second driving component; the first driving component and / or the second driving component are connected to the controller in communication. The uniform casting of a large-plane microneedle casting mold can be quickly completed.

Description

Technical Field

[0001] The present invention relates to the field of microneedle technology, and in particular to a microneedle casting system and a microneedle preparation method. Background Art

[0002] Micromolding is a high-precision micro-nano manufacturing technology that uses micro-replication molds to form microstructures. This technology has the advantages of high replication accuracy, low cost, and low residual stress, and is widely used in the preparation of micro-nano structures such as micro-gears, micro-needles, microfluidic chips, and light guides in various fields such as machinery, medicine, and biology. The most critical step in micromolding is mold filling, which is to fill the mold groove with a high filling ratio of the replication liquid material, which is a key factor affecting the replication accuracy of the microstructure.

[0003] Common mold filling methods include pressure filling, centrifugal filling and vacuum filling. Pressure filling is to use pressure to press the filling material into the mold groove. It is very difficult to process molds with high aspect ratio and high precision structures such as microneedle concave grooves by metal one-piece molding. Therefore, micro-groove molds are often made of silicon or polymer materials. However, silicon micro-groove molds are relatively brittle, and polymer micro-groove molds (such as PDMS, SU-8 glue molds) are soft in texture and have strict requirements on the imprint force, which are not suitable for mass production.

[0004] In contrast, vacuum filling has low requirements on mold material and size compatibility, and its advantages are more obvious. The existing vacuum filling method for microneedles is to spread the casting solution on the mold surface under normal pressure, then vacuum the mold to remove the residual gas inside, and the casting solution enters the mold microstructure to complete the filling replication.

[0005] Chinese patent document CN106426687A mentions a high-viscosity liquid vacuum filling device for microneedle molds. The device first completes the tiling of the casting solution, and then maintains a certain negative pressure state on the back of the microneedle mold, so that the high-viscosity liquid flows into the microneedle inverted cone pattern, achieving a better mold filling effect. However, this method requires that the microneedle mold material must have good liquid-isolating and breathable properties, and the mold thickness cannot be too thick, otherwise it will affect the residual gas inside the mold and be sucked out from the back of the mold, reducing the quality of mold filling; at the same time, if the negative pressure distribution on the back of the mold is uneven, it will further affect the consistency of mold filling. In addition, this negative pressure environment makes it difficult to ensure that the solution components do not enter the mold material at all. If the polymer (drug) in the solution penetrates into the mold, it will affect the original properties of the mold material and further affect the repeated service life of the mold.

[0006] Chinese patent document CN110582320A mentions a method for manufacturing microneedle patches. This method also introduces a liquid-permeable material to make a mold, that is, the mold is first evacuated for a period of time before use to remove the gas inside the mold, and then the mold is filled with casting liquid, and the microneedle cavity is filled by utilizing the characteristics of gas back-absorption inside the mold. This method has special requirements for the material used to make the mold. At the same time, during the process of pouring the vacuumed mold under normal pressure, when the gas inside the mold is back-absorbed, it is difficult to ensure quantifiable consistency between different parts of the same mold and between different molds. The entire casting process, including the initial mold vacuum exhaust and the gas back-absorption after filling to fill the needle body, takes a relatively long time, which is not conducive to large-scale mass production.

[0007] The art also needs a new microneedle casting system and a microneedle preparation method to solve one or more of the above problems. Summary of the invention

[0008] The technical problem to be solved by the present invention is to provide a microneedle casting system and a microneedle preparation method, which can quickly complete the uniform casting of a large-plane microneedle casting mold, realize high-precision and rapid replication of micro-nanoscale structures, use a small amount of casting solution, have precise control, high casting efficiency, good consistency, and significantly reduce costs.

[0009] In order to solve the above technical problems, the present invention provides a microneedle casting system, comprising: a vacuum chamber, a motion platform, a first motion component, a liquid filling needle component, a second motion component and a controller; the motion platform is arranged in the vacuum chamber, and is used to support the microneedle casting mold; the first motion component comprises a first transmission component and a first driving component connected to each other, the motion platform is connected to the first transmission component, and the first transmission component drives the motion platform to move along the first direction or / and the third direction under the drive of the first driving component; the liquid filling needle component is used to transport the casting solution for preparing microneedles into the vacuum chamber, and the liquid filling needle component comprises a liquid outlet head and a liquid filling needle rod, one end of the liquid filling needle rod extends into the vacuum chamber and is connected to the liquid outlet head; The second motion assembly includes a second transmission component and a second driving component that are connected to each other, the filling needle rod is connected to the second transmission component, and the second transmission component drives the filling needle assembly to move along the second direction under the drive of the second driving component; the controller is communicated with the first driving component and the second driving component respectively, and the controller is configured to control the second driving component to drive the filling needle assembly to approach the motion platform along the second direction when the vacuum chamber is in a vacuum condition, control the filling needle assembly to output a casting solution for preparing the microneedle, and control the first driving component to drive the motion platform to move along the first direction or / and the third direction; wherein: the first direction, the second direction and the third direction are perpendicular to each other.

[0010] Preferably, the first driving component is a first motor, which has an output end, and the output end of the motor shaft is connected to the first transmission component; the first transmission component includes a support frame, a guide rod, a first screw and a moving member, the first screw is rotatably arranged on the support frame along a first direction, the guide rod is arranged along the first direction, and the guide rod passes through the moving member, the moving member is realized by a threaded connection with the first screw, and moves along the first direction under the action of the guide rod and the first screw, and the motion platform is fixedly connected to the moving member.

[0011] Preferably, the first driving component is located outside the vacuum chamber, the first transmission component is located inside the vacuum chamber, and the first driving component and the first transmission component are connected via a connecting mechanism; the connecting mechanism comprises a connecting shaft, a first coupling and a second coupling, one end of the connecting shaft is connected to the output end of the first motor via the first coupling, the other end of the connecting shaft passes through the side wall and the support frame of the vacuum chamber, and is connected to the first screw via the second coupling, and the connecting shaft seal is rotatably arranged on the side wall of the vacuum chamber between the first driving component and the first transmission component.

[0012] Preferably, the first driving component is a first motor, which has an output end, and the output end of the motor shaft is connected to the first transmission component; the first transmission component includes a support frame, a second screw, a third screw and a moving member, the second screw and the third screw are rotatably arranged on the support frame along a first direction, the moving member is moved along the first direction by threaded connection with the second screw and the third screw, and the motion platform is fixedly connected to the moving member.

[0013] Preferably, the second screw has a second thread threadedly connected to the moving member, the third screw has a third thread threadedly connected to the moving member, the second screw and the third screw are driven to rotate in the same direction, and the second thread and the third thread have the same pitch and the same direction; or,

[0014] The second screw and the third screw are driven to rotate in opposite directions, and the second thread and the third thread have the same pitch and opposite thread directions.

[0015] Preferably, the first driving component is located outside the vacuum chamber, and the first transmission component is located inside the vacuum chamber. The first driving component and the first transmission component are connected via a connecting mechanism, and the connecting mechanism includes a connecting shaft and a connecting gear set. One end of the connecting shaft is connected to the output shaft of the first motor, and the other end of the connecting shaft passes through a side wall of the vacuum chamber and the support frame, and is connected to the first screw and the second screw through the connecting gear set. The connecting shaft seal is rotatably arranged on the side wall of the vacuum chamber between the first driving component and the first transmission component.

[0016] Preferably, a bearing and a sealing ring are arranged between the connecting shaft and the side wall of the vacuum chamber located between the first driving component and the first transmission component, so as to realize a seal that can be rotatably arranged on the side wall of the vacuum chamber located between the first driving component and the first transmission component.

[0017] Preferably, the second driving component is a second motor, and the second transmission component includes a column, a slide rail and a slider, the column is fixedly arranged in the vacuum chamber, the slide rail is arranged on the column along the second direction, one side of the slider is movably connected to the slide rail, and the other side of the slider is fixedly connected to the filling needle rod, and the slide rail is driven by the second motor to drive the filling needle assembly to move along the second direction.

[0018] Preferably, the filling needle assembly further comprises a pressure reducing valve, which is arranged in the filling needle rod and is used to achieve one or more functions of pressure reduction, pressure stabilization and back suction of the pouring solution.

[0019] Preferably, the pressure reducing valve comprises a valve body, an inner cavity is formed in the valve body, a first sliding valve and a second sliding valve can be arranged in the inner cavity at intervals along the axial direction, the first sliding valve and the second sliding valve are movable relative to the inner cavity, an inflow channel, an inflow hole, an outflow hole and an outflow channel are arranged on the valve body, the inflow channel and the outflow channel are blind holes, and the inflow channel and the outflow channel are extended along the axial direction on the valve body; the inflow channel and the inner cavity are connected through the inflow hole, the outflow channel and the inner cavity are connected through the outflow hole, and the inner cavity is divided into a first chamber, a cavity channel and a second chamber in sequence according to the inflow hole and the outflow hole; the first sliding valve is configured as follows: in the initial state, it is subjected to the action of the first elastic force and is maintained in the first position The first slide valve is configured to be positioned in a second position under the action of a second elastic force in an initial state to block the communication between the cavity channel and the outflow channel between the first slide valve and the second slide valve; and when subjected to a first axial pressure of the casting solution greater than the first elastic force, the first slide valve overcomes the action of the first elastic force and moves in an axial direction from the first position to the first chamber to communicate with the cavity channel and the inflow channel. The second slide valve is configured to be maintained in a second position under the action of a second elastic force in an initial state to block the communication between the cavity channel and the outflow channel between the first slide valve and the second slide valve; and when subjected to a second axial pressure of the casting solution greater than the second elastic force, the first slide valve overcomes the action of the second elastic force and moves in an axial direction from the second position to the second chamber to communicate with the cavity channel between the first slide valve and the second slide valve.

[0020] Preferably, the first sliding valve is further configured to return to the first position under the action of the first elastic force when subjected to a first axial pressure of the casting solution that is less than the first elastic force or is no longer subjected to the first axial pressure of the casting solution; the second sliding valve is further configured to return to the second position under the action of the second elastic force when subjected to a second axial pressure of the casting solution that is less than the second elastic force or is no longer subjected to the second axial pressure of the casting solution.

[0021] Preferably, a damping hole is further provided on the cavity wall of the first cavity, and the outflow channel and the first cavity are communicated through the damping hole.

[0022] Preferably, the pressure reducing valve also includes a first fixing member and a second fixing member, the inner cavity has a third end and a fourth end, the first fixing member is fixed to the end of the third end of the inner cavity, and the second fixing member is fixed to the end of the fourth end of the inner cavity; a first elastic structure is provided in the first chamber for providing the first elastic force, one end of the first elastic structure abuts against the first sliding valve, and the other end of the first elastic structure abuts against the first fixing member; a second elastic structure is provided in the second chamber for providing the second elastic force, one end of the second elastic structure abuts against the second sliding valve, and the other end of the second elastic structure abuts against the second fixing member.

[0023] Preferably, the first sliding valve includes a first sliding valve body, the first sliding valve body is provided with a hollow first stop column along the axial extension in the first chamber, and the first elastic structure is placed in the first stop column; the second sliding valve includes a second sliding valve body, the second sliding valve body is provided with a hollow second stop column along the axial extension in the second chamber, and the second elastic structure is placed in the second stop column.

[0024] Preferably, the first fixing member is further provided with a first groove, and the first groove is used to accommodate the first gear column; the second fixing member is further provided with a second groove, and the second groove is used to accommodate the second gear column.

[0025] Preferably, the first groove extends toward the first sliding valve to form a first protrusion, and the other end of the first elastic structure is sleeved outside the first protrusion; the second groove extends toward the second sliding valve to form a second protrusion, and the other end of the second elastic structure is sleeved outside the second protrusion.

[0026] Preferably, a damping hole is further provided on the cavity wall of the first chamber, and the outflow channel and the first chamber are connected through the damping hole; the distance between the damping hole and the first position is greater than the distance between the open end of the first baffle column and the bottom of the first groove.

[0027] Preferably, the valve body is provided with a first valve seat and a second valve seat, the first valve seat is used to keep the first sliding valve in a first position to prevent the first sliding valve from approaching the second sliding valve; the second valve seat is used to keep the second sliding valve in a second position to prevent the second sliding valve from approaching the first sliding valve.

[0028] Preferably, a back-suction hole is further provided on the valve body, the outflow channel is communicated with the inner cavity through the back-suction hole, and the back-suction hole is located between the outflow hole and the outlet of the outflow channel.

[0029] Preferably, the first sliding valve is a piston, and the piston has an inclined surface for causing the casting solution to generate a first axial pressure of the casting solution on the piston.

[0030] Preferably, the filling needle assembly further comprises a filling pump, one end of the filling needle rod away from the end of the liquid outlet head is connected to the filling pump, and the filling pump is communicatively connected to the controller.

[0031] Preferably, a mixing tank is further included, which is connected to the filling pump and is used to evenly mix various raw materials for preparing microneedles to form a casting solution for preparing microneedles.

[0032] Preferably, the other end of the filling needle rod is connected to a pressure relief valve, and the pressure relief valve is respectively connected to the filling needle rod and the filling pump through a hose, so as to discharge the liquid pressure in the filling needle rod.

[0033] Preferably, it comprises a vacuum valve and a vacuum pump, wherein the vacuum valve is connected to the vacuum chamber, and the vacuum pump acts on the vacuum chamber through the vacuum valve to maintain a negative pressure state in the vacuum chamber.

[0034] Preferably, a vacuum vent valve is included, and the vacuum vent valve is arranged in the vacuum chamber to complete the vacuum breaking of the vacuum chamber.

[0035] Preferably, the vacuum chamber is connected to a vacuum gauge, and the vacuum gauge is communicatively connected to the controller for obtaining the vacuum condition of the vacuum chamber.

[0036] Preferably, a display is included, and the display is communicatively connected to the controller to display the status of the system.

[0037] The present invention also provides a microneedle preparation method, which adopts the above-mentioned microneedle casting system, including the following steps: S1: placing the microneedle casting mold on the moving platform and closing the vacuum chamber; and evacuating the vacuum chamber and maintaining the vacuum state; S2: the second driving component drives the filling needle assembly to move to a specified position along the second direction, and fills the filling needle assembly with liquid. At the same time, the moving platform drives the microneedle casting mold to move along the first direction and / or the third direction. When the casting of the microneedle casting mold is completed, the filling is stopped; S3: the vacuum chamber is restored to normal pressure, the chamber door of the vacuum chamber is opened, and the filled microneedle casting mold is taken out.

[0038] Preferably, the microneedle casting system comprises a display connected to the controller, a filling pump connected to the filling needle rod, a mixing tank connected to the filling pump, a vacuum valve and a vacuum gauge connected to the vacuum chamber, a vacuum pump and a vacuum venting valve connected to the vacuum valve, and the filling pump, the vacuum gauge, the vacuum pump, the vacuum venting valve, and the vacuum valve are all connected to the controller, and comprises the following steps: S11: setting process parameters on the display, adding solution configuration raw materials to the mixing tank, and after mixing, placing the microneedle casting mold on the moving platform and closing the vacuum chamber; S21: clicking on the display to start the casting program, opening the vacuum valve, and the vacuum pump evacuates the vacuum chamber; S31: When the vacuum gauge detects that the vacuum value of the vacuum chamber reaches a first set value, the vacuum pump stops working and the vacuum valve is closed to maintain the vacuum state in the vacuum chamber; S41: The second driving component drives the filling needle assembly to move along the second direction to a specified position, and the filling pump starts to fill the filling needle assembly with liquid. At the same time, the motion platform drives the microneedle casting mold to move along the first direction and / or the third direction. When the casting of the microneedle casting mold is completed, the filling pump stops working, and the motion platform and the filling needle assembly are reset to the initial position; S51: Open the vacuum vent valve to restore the vacuum chamber to normal pressure, open the chamber door of the vacuum chamber, and take out the filled microneedle casting mold.

[0039] Compared with the prior art, the present invention has the following beneficial effects: the microneedle pouring system and microneedle preparation method provided by the present invention can realize the uniform paving of the large-surface filling mold plane under a wide range of filling amounts by configuring a motion platform of the microneedle pouring mold in the vacuum chamber, realize high-precision and rapid replication of micro-nanoscale structures, use less pouring solution, and have high pouring efficiency; through the combination of the vacuum chamber, the filling needle, and the motion platform, the vacuum chamber can complete the pouring of solutions of different viscosities under a high negative pressure state, and the pressure difference after pouring ensures that the solutions can flow into the micro-nanostructure under the surface of the mold, thereby ensuring the mold replication accuracy and consistency. In particular, a pressure reducing valve is arranged in the filling needle, which can continuously spray liquid in a wide range when filling solutions of different viscosities, ensuring that less pouring solution is paved on the surface of the mold, which has obvious advantages over other pouring methods. The vacuum chamber is connected to a vacuum pump and a vacuum gauge, and the vacuum chamber can be evacuated before or during solution filling, so that a high negative pressure state is maintained in the vacuum chamber, so that the pouring solution flows into the micro-nanostructure under the surface of the mold, removes residual gas in the microstructure, and ensures the mold replication accuracy. The entire pouring process is controlled by a control system, which uses less liquid and has high efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 Schematic diagram of the overall structure of the microneedle gating system in an embodiment of the present invention;

[0041] Figure 2 It is a schematic diagram of the structure of the vacuum chamber in an embodiment of the present invention;

[0042] Figure 3 It is a partial structural schematic diagram of a moving platform and a liquid discharge head of a liquid filling needle in one embodiment of the present invention;

[0043] Figure 4 It is a partial structural schematic diagram of a moving platform and a liquid discharge head of a liquid filling needle in another embodiment of the present invention;

[0044] Figure 5 It is a partial cross-sectional schematic diagram of the liquid outlet head of the filling needle in the embodiment of the present invention;

[0045] Figure 6 It is a cross-sectional schematic diagram of a filling needle pressure reducing valve in an embodiment of the present invention;

[0046] Figure 7 A bottom view of the liquid filling needle pressure reducing valve in an embodiment of the present invention;

[0047] Figure 8 Schematic diagram of the overall structure of the pressure reducing valve in the embodiment of the present invention;

[0048] Fig. 9 is a cross-sectional schematic diagram of a pressure reducing valve according to an embodiment of the present invention;

[0049] Fig.10 Schematic diagram of the structure of the piston of the pressure reducing valve in an embodiment of the present invention;

[0050] Fig.11 Schematic diagram of the structure of the diaphragm of the pressure reducing valve in the embodiment of the present invention;

[0051] Fig.12 Schematic diagram of the structure of the microneedle casting mold in an embodiment of the present invention.

[0052] In the figure:

[0053] 1-vacuum chamber, 2-vacuum pump, 3-controller, 4-display, 5-mixing tank, 6-filling pump, 7-first motion component, 8-motion platform, 9-second motion component, 10-vacuum gauge, 11-filling needle component, 12-vacuum valve, 13-vacuum deflation valve, 14-microneedle casting mold, 71-first motor, 72-first transmission component, 73-connecting shaft, 74-first coupling, 75-second coupling, 711-output end, 721-support frame, 722-first guide rod, 723-second guide rod, 724-moving part, 725-first screw, 726-second screw, 727-third screw, 728-connecting gear set, 91-second motor, 92-column, 93-slide rail, 94-slider, 11-1 liquid outlet head, 11-2 pressure relief valve, 11-3 pressure reducing valve, 11-4 filling needle rod , 11-30, valve body, 11-31 piston, 11-32 diaphragm, 11-33 inflow channel, 11-34 inflow hole, 11-35 outflow hole, 11-36 damping hole, 11-37 outflow channel, 11-38 outflow hole, 11-300 cavity channel, 11-301-first fixing component, 11-302-second fixing component, 11-391 first compression spring, 11-392 second compression spring, 11-310-piston body, 11-311 first chamber, 11-312 piston seat, 11-313 first stop column, 11-314 first protrusion, 11-315-inclined surface, 11-320-diaphragm body, 11-321 second chamber, 11-322 diaphragm seat, 11-323 second stop column, 11-324 second protrusion, 11-371 back suction hole, 101-side wall, 102-top wall,

[0054] 141-concave cavity, 142-concave hole of microneedle body. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0056] The present embodiment provides a microneedle casting system, including: a vacuum chamber 1, a vacuum pump 2, a controller 3, a display system 4, a mixing tank 5, a filling pump 6, a first motion component 7, a motion platform 8, a second motion component 9, a vacuum gauge 10, a filling needle assembly 11, a vacuum valve 12, and a vacuum release valve 13.

[0057] like Figure 1 As shown, the vacuum chamber 1 is used to provide a closed environment so as to prepare microneedles under vacuum conditions. The motion platform 8 is disposed in the vacuum chamber 1. In this embodiment, the motion platform 8 is unidirectional and is used to support the microneedle casting mold 14. Figure 8As shown, the microneedle casting mold 14 includes a concave cavity 141 for preparing microneedles, and the bottom surface of the concave cavity 141 is densely covered with microneedle body concave holes 142. The shape, size, arrangement shape and density of the microneedle body concave holes 142 match the microneedles to be prepared. This embodiment has no particular restrictions on the vacuum conditions when preparing microneedles. Those skilled in the art can determine the specific vacuum conditions based on the performance of the preparation material of the microneedles, the structure, density, size and other factors of the microneedles.

[0058] like Figure 1-3 As shown, the first motion component 7 is connected to the controller 3 for driving the motion platform 8 to move along a first direction. Figure 2left and right directions. Further, the first motion assembly 7 includes a first driving component and a first transmission component 72. The first driving component is a first motor 71. In the present embodiment, the first motor 71 performs rotational motion. The first transmission component 72 is used to convert the rotational motion of the first motor 71 into a linear motion of the motion platform 8 in the first direction. Further, the first transmission component 72 includes a support frame 721, a first guide rod 722, a second guide rod 723, a moving member 724 and a first screw 725. The first guide rod 722 and the second guide rod 723 are arranged on the support frame 721 along the first direction, and the first guide rod 722 and the second guide rod 723 are penetrated by the moving member 724. The first screw 725 is rotatably arranged on the support frame 721 along the first direction. The moving member 724 is transmission-connected to the first motor 71, and the first screw 725 is threadedly connected to the moving member 724. The motion platform 8 is fixed on the moving member 724 to drive the movement of the microneedle casting mold 14. Specifically, when the output end 711 of the first motor 71 performs a rotational motion, the first screw 725 is driven to perform a rotational motion. Since the moving member 724 is threadedly connected to the first screw 725, and under the constraint of the first guide rod 722 and the second guide rod 723, the moving member 724 can be driven to perform a linear motion in the first direction, thereby driving the motion platform 8 fixed on the moving member 724 to perform a linear motion in the first direction. More specifically, the first motor 71 is located outside the vacuum chamber 1, the first transmission component 72 is located inside the vacuum chamber 1, and the first motor 71 and the first transmission component 72 are connected by a connecting mechanism. The connecting mechanism includes a connecting shaft 73, a first coupling 74 and a second coupling 75. One end of the connecting shaft 73 is connected to the output end 711 of the first motor 71 through the first coupling 74, and the other end of the connecting shaft 73 passes through the side wall 101 of the vacuum chamber 1 between the first driving component and the first transmission component, and is connected to the first screw 725 through the second coupling 75. A bearing and a sealing ring are provided between the connecting shaft 73 and the side wall 101 of the vacuum chamber 1 between the first driving component and the first transmission component to achieve a sealed rotation connection. In some alternative embodiments, the first motion component 7 is configured to drive the motion platform 8 to move in a first direction and a third direction, wherein the first direction is perpendicular to the third direction, for example, the first direction is Figure 2 The third direction is the direction perpendicular to the paper surface; the present invention does not impose any special restrictions on this, and those skilled in the art can configure the motion platform 8 to perform horizontal unidirectional or multi-directional motion as needed. In other embodiments, the first motor 71 can also be placed inside the vacuum chamber 1, and the first motor 71 can be a stepper or servo motor. In this embodiment, there are two guide rods, namely the first guide rod 722 and the second guide rod 723. In alternative embodiments, there can be one guide rod or more than two guide rods.

[0059] In another embodiment, Figure 4 As shown, the first transmission component 72 comprises a support frame 721, a second screw rod 726, a third screw rod 727 and a moving member 724. The second screw rod 726 and the third screw rod 727 are rotatably arranged on the support frame 721 along the first direction, and are threadedly connected with the moving member 724, so as to drive the moving member 724 to move along the first direction. For example, the second screw rod 726 and the third screw rod 727 are provided with external threads, and the moving member 724 is provided with internal threads, and the external threads of the second screw rod 726 and the third screw rod 727 have equal pitches, and the screw direction is the same. Specifically, when the output end 711 of the first motor 71 performs rotational motion, the second screw rod 726 and the third screw rod 727 are driven to perform rotational motion, and because the moving member 724 is threadedly connected with the second screw rod 726 and the third screw rod 727, the moving member 724 is driven to perform linear motion in the first direction, and then the motion platform 8 fixed on the moving member 724 is driven to perform linear motion in the first direction. More specifically, the first motor 71 is located outside the vacuum chamber 1, the first transmission component 72 is located inside the vacuum chamber 1, and the first motor 71 and the first transmission component 72 are connected via a connecting mechanism. The connecting mechanism includes a connecting shaft 73, a first coupling 74, and a connecting gear set 728. One end of the connecting shaft 73 is connected to the output end 711 of the first motor 71 through the first coupling 74, and the other end of the connecting shaft 73 passes through the side wall 101 of the vacuum chamber 1 between the first driving component and the first transmission component, and is connected to the second screw 726 and the third screw 727 through the connecting gear set 728. The second screw 726 has a second thread threadedly connected to the moving member, and the third screw has a third thread threadedly connected to the moving member 724. When the second screw 726 and the third screw 727 are driven to rotate in the same direction, the second thread and the third thread have the same pitch and the same thread direction; or, the second screw 727 and the third screw 728 are driven to rotate in opposite directions, and the second thread and the third thread have the same pitch and opposite thread directions.

[0060] Please continue to see Figure 1-2 and Figure 5, the filling needle assembly 11 includes a filling needle rod 11-4, a filling pump 6 and a liquid outlet head 11-1. The filling needle assembly 11 is used to transport the casting solution for preparing microneedles into the vacuum chamber 1. Specifically, the filling needle rod 11-4 includes a first end and a second end. The first end of the filling needle rod 11-4 passes through the top wall 102 of the vacuum chamber 1 and enters the interior of the vacuum chamber 1 and is connected to the liquid outlet head 11-1. The second end of the filling needle rod 11-4 is connected to the filling pump 6 through a hose, and the filling pump 6 can be a plunger pump, a screw pump, a peristaltic pump, etc. Preferably, the filling needle assembly 11 also includes a pressure reducing valve 11-3. The pressure reducing valve 11-3 is arranged inside the filling needle rod 11-4, and can realize one or more functions of pressure reduction, pressure stabilization, and back suction of the casting solution. The pressure reducing valve 11-3 and the filling needle rod 11-4 can be optionally threaded or tightly fixed. More preferably, as Figure 3 , Figure 4 and Figure 5 As shown, the liquid outlet head 11-1 is a flat-mouthed head, and the liquid outlet head 11-1 and the filling needle rod 11-4 are detachably connected or integrally formed, and the liquid outlet head 11-1 has a liquid outlet extending perpendicular to the third direction, and the liquid outlet cross-section of the liquid outlet head 11-1 can be square, rectangular, torus, trumpet-shaped, etc. The size of the liquid outlet head 11-1 can be customized according to the pouring solution. Preferably, the size of the liquid outlet head 11-1 extending perpendicular to the third direction is smaller than the size of the microneedle pouring mold 14 in the third direction, so that a wide range of liquid spraying can be achieved. More preferably, the liquid outlet of the liquid outlet head 11-1 has a length of 1cm-40cm and a width of 0.05mm-5mm.

[0061] like Figure 2 As shown, the filling needle assembly 11 is driven by the second motion assembly 9 to move closer to or farther from the motion platform 8 along the second direction. The second direction is perpendicular to the first direction and the third direction. In this embodiment, the second direction is Figure 2 The second motion assembly 9 includes a second driving component and a second transmission component, the second driving component is a second motor 91, and the second transmission component includes a column 92, a slide rail 93 and a slider 94. The column 92 can be placed on a frame or fixed on the top wall 102 of the vacuum chamber 1; the slide rail 93 is arranged on the column 92 along the second direction, one side of the slider 94 is movably connected to the slide rail 93, and the other side of the slider 94 is fixedly connected to the filling needle rod 11-4. Specifically, the slide rail 93, driven by the second motor 91, drives the slider 94 to move along the second direction, thereby driving the filling needle assembly 11 to move along the second direction. The second motor 91 can be a stepping motor or a servo motor, etc., and the lifting range of the filling needle assembly 11 (such as the liquid outlet head 11-1) in the second direction is preferably 0-20cm.

[0062] See also Figure 6 , Figure 8 and Fig. 9 In one embodiment, the pressure reducing valve 11-3 includes a valve body 11-30, and an inner cavity is formed in the valve body 11-30. A first sliding valve and a second sliding valve are arranged in the inner cavity along the axial direction, and the first sliding valve and the second sliding valve are movable relative to the inner cavity. The first sliding valve and the second sliding valve can be pistons or diaphragms. In this embodiment, the first sliding valve is a piston 11-31 and the second sliding valve is a diaphragm 11-32 for detailed description. In other embodiments, it can be flexibly configured according to actual needs, such as the first sliding valve is a diaphragm, the second sliding valve is a piston, or the first sliding valve and the second sliding valve are both pistons or diaphragms, and the present invention does not impose any special restrictions on this.

[0063] The valve body 11-30 is provided with an inflow channel 11-33, an inflow hole 11-34, an outflow hole 11-35, a damping hole 11-36, and an outflow channel 11-37. Among them, the inflow channel 11-33 is a blind hole for allowing the casting solution to flow in, and the inflow channel 11-33 is axially extended and arranged on the valve body 11-30. Preferably, there are multiple inflow channels 11-33, and the multiple inflow channels 11-33 are evenly distributed on the valve body 11-30 along the circumferential direction. This embodiment has no special restriction on the number of inflow channels 11-33 and inflow holes 11-34, for example, one, two, four, five, six, eight, or ten. Figure 8 , Fig. 9 In the embodiment shown, the number of the inflow channels 11-33 is two. The open end of the inflow channel 11-33 is closer to the second end of the filling needle rod 11-4. The inflow hole 11-34 is provided on the cavity wall of the inner cavity, and is used to connect the inflow channel 11-33 with the inner cavity. The number of the inflow holes 11-34 is the same as the number of the inflow channels 11-33.

[0064] Similarly, the outflow channel 11-37 is a blind hole for allowing the pouring solution to flow out, and the outflow channel 11-37 is distributed axially on the valve body 11-30. Further, the pressure reducing valve also includes an outflow hole 11-38 connected to the outflow channel 11-37. The open end of the outflow channel 11-37 is closer to the first end of the filling needle rod 11-4. The outflow hole 11-35 is arranged on the cavity wall of the inner cavity, and is used to connect the outflow channel 11-37 with the inner cavity. This embodiment has no special restrictions on the number of outflow holes 11-35, outflow channels 11-37, and outflow holes 11-38, for example, one, two, four, five, six, eight, or ten. Preferably, there are multiple outflow channels 11-37, and they are evenly distributed circumferentially on the valve body 11-30. The number of outflow holes 11-35 and outflow holes 11-38 may be consistent with the number of outflow channels 11-37. In this case, the outlet of the outflow channel 11-37 may be directly connected to the outflow holes 11-38. The number of outflow holes 11-38 may be inconsistent with the number of outflow channels 11-37. Preferably, the number of outflow holes 11-38 is greater than the number of outflow channels 11-37 to achieve rapid outflow of the casting solution. Figure 7 In the embodiment shown, the number of the outflow channels 11-37 is two, and the number of the outflow holes 11-38 is eight. At this time, an annular groove is provided between the outflow channel 11-37 and the outflow hole 11-38 to connect the outflow channel 11-37 and the outflow hole 11-38. The plurality of outflow holes 11-38 are evenly distributed in the circumferential direction. According to the positions of the inflow hole 11-34 and the outflow hole 11-35, the inner cavity is divided into a first chamber 11-311, a cavity channel 11-300 and a second chamber 11-321 in sequence. In this embodiment, the inner cavity includes a third end and a fourth end. The third end is closer to the second end of the filling needle rod 11-4 than the fourth end. The inner cavity between the third end and the inflow hole 11-34 is the first chamber 11-311, the inner cavity between the inflow hole 11-34 and the outflow hole 11-35 is the cavity channel 11-300, and the inner cavity between the outflow hole 11-35 and the fourth end is the second chamber 11-321.

[0065] The piston 11-31 is configured such that, in the initial state, under the action of the first elastic force, the piston 11-31 is maintained in the first position, and the piston 11-31 abuts against the inflow hole 11-34 to block the communication between the cavity channel 11-300 and the inflow channel 11-33; when subjected to a first axial pressure of the casting solution greater than the first elastic force, the piston 11-31 overcomes the first elastic force and moves from the first position to the first chamber 11-311 in the axial direction to enable the cavity channel 11-300 to communicate with the inflow channel 11-33. Further, when subjected to a first axial pressure of the casting solution less than the first elastic force or no longer subjected to the first axial pressure of the casting solution, the piston 11-31 returns to the first position under the action of the first elastic force, abuts against the inflow hole 11-34 to block the communication between the cavity channel 11-300 and the inflow channel 11-33. In a preferred embodiment, the first position is located at a position where the inflow hole 11-34 and the cavity channel 11-300 are connected. The diaphragm 11-32 is configured such that, in the initial state, under the action of the second elastic force, the diaphragm 11-32 is maintained in the second position to block the connection between the cavity channel 11-300 between the piston 11-31 and the diaphragm 11-32 and the outflow channel 11-37; when the diaphragm 11-32 is subjected to a second axial pressure of the casting solution greater than the second elastic force, the diaphragm 11-32 overcomes the second elastic force and moves along the inner cavity axial direction from the second position to the second chamber 11-321, so that the cavity channel 11-300 between the piston 11-31 and the diaphragm 11-32 is connected with the outflow channel 11-37. Similarly, when subjected to a second axial pressure of the casting solution less than the second elastic force or no longer subjected to the second axial pressure of the casting solution, the diaphragm 11-32 returns to the second position under the action of the second elastic force to block the connection between the cavity channel 11-300 between the piston 11-31 and the diaphragm 11-32 and the outflow channel 11-37. In a preferred embodiment, the second position is located between the first position and the outflow hole 11-35. The first axial pressure and the second axial pressure may be equal or unequal.

[0066] In this embodiment, if Figure 6 and Fig. 9As shown, the piston 11-31 is located above the diaphragm 11-32. Correspondingly, the first chamber 11-311 is located above the cavity channel 11-300, and the cavity channel 11-300 is located above the second chamber 11-321. The pressure reducing valve 11-3 also includes a first fixing member 11-301 and a second fixing member 11-302. The first fixing member 11-301 is fixed to the end of the third end of the inner cavity; the second fixing member 11-302 is fixed to the end of the fourth end of the inner cavity. Therefore, the first chamber 11-311 is jointly defined by the first fixing member 11-301 and the inflow hole 11-34; the second chamber 11-321 is jointly defined by the second fixing member 11-302 and the outflow hole 11-35.

[0067] The pressure reducing valve 11-3 also includes a first valve seat and a second valve seat. The first valve seat is used to keep the first slide valve in the first position and prevent the first slide valve from approaching the second slide valve; the second valve seat is used to keep the second slide valve in the second position and prevent the second slide valve from approaching the first slide valve. In this embodiment, the first position is the position where the inflow hole 11-34 and the cavity channel 11-300 are connected; the second position is set between the first position and the outflow hole 11-35. The first valve seat is a piston seat 11-312; the second valve seat is a diaphragm seat 11-322. The piston seat 11-312 is used to prevent the piston 11-31 from approaching the diaphragm 11-32; the diaphragm seat 11-322 is used to prevent the diaphragm 11-32 from approaching the piston 11-31. Specifically, the piston seat 11-312 is a first step portion provided on the valve body 11-30, and the shape of the first step portion matches the shape of the piston 11-32; the diaphragm seat 11-322 is a second step portion provided on the valve body 11-30, and the shape of the second step portion matches the shape of the diaphragm 11-32. Fig.10 As shown, the piston 11-31 has a slope 11-315 so that the first force exerted by the casting solution on it can have an axial component.

[0068] Please also see Figure 6 , Fig. 9 and Fig.10, a first elastic structure, such as a first compression spring 11-391, is provided in the first chamber 11-311, and the first elastic structure is used to provide a first elastic force. Specifically, one end of the first compression spring 11-391 abuts against the piston 11-31, and the other end of the first compression spring 11-391 abuts against the first fixing member 11-301. Further, the piston 11-31 includes a piston body 11-310, which is used to abut the end of the inflow channel 11-33 at one end of the cavity channel 11-300 at a first position to block the connection between the cavity channel 11-300 and the inflow channel 11-33. In addition to the inclined surface 11-315, the piston body 11-310 is also provided with a hollow first stop column 11-313 extending in the direction of the first fixing member 11-301. The inner diameter of the first stop column 11-313 is slightly larger than the outer diameter of the first compression spring 11-391 to accommodate the first compression spring 11-391 and prevent the first compression spring 11-391 from moving, shaking or twisting in the radial direction. Furthermore, the first fixing member 11-301 is also provided with a first groove, and the first groove is used to accommodate the first stop column 11-313. Furthermore, the bottom of the first groove extends toward the piston 11-31 to form a first protrusion 11-314. The end of the first compression spring 11-391 is sleeved on the outside of the first protrusion 11-314 to further prevent the first compression spring 11-391 from moving, shaking or twisting in the radial direction. In the initial state, there is a certain distance between the open end of the first stop column 11-313 and the bottom of the first groove to ensure space for the piston 11-31 to move in the axial direction.

[0069] Please also see Figure 6 , Fig. 9 and Fig.11, a second elastic structure, such as a second compression spring 11-392, is provided in the second chamber 11-321, and the second elastic structure is used to provide a second elastic force. Specifically, one end of the second compression spring 11-392 abuts against the diaphragm 11-32, and the other end of the second compression spring 11-392 abuts against the second fixing member 11-302. Further, the diaphragm 11-32 includes a diaphragm body 11-320, and the diaphragm body 11-320 is provided with a hollow second stop column 11-323 extending in the direction of the second fixing member 11-302. The inner diameter of the second stop column 11-323 is slightly larger than the outer diameter of the second compression spring 11-392 to accommodate the second compression spring 11-392 and prevent the second compression spring 11-392 from moving, shaking or twisting in the radial direction. Further, the second fixing member 11-302 is also provided with a second groove, and the second groove is used to accommodate the second stop column 11-323. Furthermore, the bottom of the second groove extends toward the diaphragm 11-32 to form a second protrusion 11-324. The end of the second compression spring 11-392 is sleeved outside the second protrusion 11-324 to further prevent the second compression spring 11-392 from moving, shaking or twisting in the radial direction. In the initial state, there is a certain distance between the open end of the second stop column 11-323 and the bottom of the second groove to ensure space for the diaphragm 11-32 to move in the axial direction.

[0070] Further, a damping hole 11-36 is provided on the cavity wall of the first chamber 11-311, and the outflow channel 11-37 and the first chamber 11-311 are connected through the damping hole 11-36. The damping hole 11-36 is used to achieve that the pressure in the first chamber 11-311 between the piston 11-31 and the first fixing member 11-301 remains stable when the piston 11-31 moves. Preferably, the distance between the damping hole 11-36 and the first position is greater than the distance between the open end of the first stop column 11-313 and the bottom of the first groove, so as to prevent the piston 11-31 from blocking the damping hole 11-36.

[0071] Furthermore, a back-suction hole 11-371 is provided on the cavity wall of the second chamber 11-321, and the outflow channel 11-37 is connected to the second chamber 11-321 through the back-suction hole 11-371. The back-suction hole 11-371 is used to discharge the casting solution that is back-sucked in the second chamber 11-321. When the diaphragm 11-32 is reset to the second position, the casting solution will flow back into the inner cavity defined by the diaphragm 11-32 and the second fixing member 11-302. If it is not discharged in time, the diaphragm 11-32 will be unable to move toward the second fixing member 11-302. Therefore, it is necessary to provide a back-suction hole 11-371 on the cavity wall of the second chamber 11-321. Preferably, the position of the back-suction hole 11-371 is configured to be at one end of the second fixing member 11-302 close to the diaphragm 11-32.

[0072] When the pressure reducing valve 11-3 of this embodiment is in use, the casting solution enters the inflow hole 11-34 through the inflow channel 11-33 of the pressure reducing valve 11-3, and applies a first force to the piston 11-31; when the first force overcomes the first elastic force, the piston 11-31 moves toward the first fixing part 11-301 to the first chamber 11-311, the inflow hole 11-34 is connected with the cavity channel 11-300, and the casting solution enters the cavity channel 11-300; then the casting solution in the cavity channel 11-300 applies a second force to the diaphragm 11-32; when the second force is greater than the second elastic force, the diaphragm 11-32 moves toward the second fixing part 11-302 to the second chamber 11-321, the outflow hole 11-35 is connected with the cavity channel 11-300, the casting solution enters the outflow channel 11-37, and finally flows out from the outflow hole 11-38. After the pouring solution is stopped from being supplied to the pressure reducing valve 11-3, when the second force applied to the diaphragm 11-32 is less than the second elastic force, the diaphragm 11-32 moves toward the piston 11-31 and remains in the second position to block the connection between the cavity channel 11-300 between the piston 11-31 and the diaphragm 11-32 and the outflow hole 11-35; when the first force applied to the piston 11-31 is less than the first elastic force, the piston 11-31 moves toward the diaphragm 11-32 and remains in the first position to block the connection between the inflow hole 11-34 and the cavity channel 11-300.

[0073] In this embodiment, the axial pressure of the solution and the elastic force of the first elastic structure and the second elastic structure are balanced, and the internal throttling effect of the pressure reducing valve 11-3 is added to achieve the decompression effect of the pouring solution, and can prevent the pouring solution from being ejected when it flows out of the filling needle rod 11-4 under a vacuum environment. Further, the outflow channel 11-37 is connected with the damping hole 11-36, so that when the piston 11-31 moves toward the first fixing part, the first chamber 11-311 discharges pressure outward through the outflow channel 11-37; and the pressure of the outflow hole 11-38 is fed back to the first chamber 11-311 through the outflow channel 11-37 and then fed back to the piston 11-31. Therefore, the setting of the damping hole 11-36 makes the output pressure of the pouring solution more stable when the piston 11-31 reciprocates in the axial direction. When pouring is stopped and the pouring liquid pressure in the pouring pipeline disappears, the piston 11-31 and the diaphragm 11-32 are reset to the first position and the second position respectively under the action of the first elastic force and the second elastic force. At the same time, the solution is sucked back through the outflow hole 11-35 to avoid hanging droplets at the liquid outlet of the filling needle, which greatly reduces the dripping caused by repeated vacuuming when the filling needle assembly is repeatedly filled, thereby improving the filling accuracy and microneedle quality.

[0074] More preferably, a pressure relief valve 11-2 is connected between the filling needle rod 11-4 and the filling pump 6, and the pressure relief valve 11-2 is respectively connected to the filling needle rod 11-4 and the filling pump 6 through a hose. In addition, the pressure relief valve 11-2 is configured to be opposite to the switch signal of the filling pump 6, but completely synchronized. When the filling needle 11 completes a single filling, the filling pump 6 is shut down and the pressure relief valve 11-2 is opened to eliminate the liquid pressure in the filling needle rod 11-4. At this time, the piston 11-31 and the diaphragm 11-32 are reset to the initial position under the action of the first elastic force and the second elastic force, and the quantitative solution is sucked back while resetting, which greatly reduces the dripping of the filling needle assembly 11 during repeated filling, and improves the filling accuracy and the quality of the microneedles.

[0075] The mixing tank 5 is used to evenly mix various raw materials for preparing microneedles to form a casting solution for preparing microneedles. The mixing tank 5 can complete material mixing and stirring; more preferably, the mixing tank 5 can achieve material dispersion, homogenization, emulsification, etc. The filling pump 6 is connected to the controller 3 and is connected to the mixing tank 5 to pump the mixed casting solution to the liquid outlet 11-1. In this way, the mixing tank 5 can continuously feed the filling pump 6 to complete continuous batch casting.

[0076] The vacuum valve 12 is arranged in the vacuum chamber 1, and is used to open or disconnect the vacuum pipeline. The vacuum pump 2 acts on the vacuum chamber 1 through the vacuum valve 12. And the vacuum pump 2 is connected to the controller 3 for communication. The vacuum pump 2 is used to evacuate the vacuum chamber 1 before and / or during solution filling, so that the vacuum chamber 1 maintains a negative pressure state. After filling, due to the internal and external pressure difference of the microneedle casting mold 14, the casting solution can flow into the microneedle needle body concave hole 142 under the surface of the microneedle casting mold 14, thereby ensuring the replication accuracy of the microneedle casting mold 14. The vacuum pump 2 can be selected as an oil pump or a dry pump.

[0077] The vacuum gauge 10 is connected to the controller 3 for communication, and is disposed in the vacuum chamber 1 for detecting the vacuum condition of the vacuum chamber 1, such as the vacuum degree, and feeding back the vacuum condition to the controller 3. The vacuum vent valve 13 is disposed in the vacuum chamber 1 for completing the vacuum breaking of the vacuum chamber 1. The vacuum pump 2 cooperates with the vacuum gauge 10, and the vacuum degree of the vacuum chamber 1 is controlled as a whole by the controller 3. Preferably, the vacuum valve 12 is an electronic vacuum valve, and the vacuum vent valve 13 is an electronic vacuum vent valve, both of which are controlled by the controller 3.

[0078] The display 4 serves as an input and output device of the system and is connected in communication with the controller 3 to receive external instructions and display the status of the system. The controller 3 uniformly controls the operation of the entire microneedle casting system. The controller 3 is connected in communication with the first drive component and the second drive component, and is configured to control the second drive component to drive the filling needle assembly to approach the motion platform along the second direction when the vacuum chamber 1 is in a vacuum condition, control the filling needle assembly to transport the microneedle preparation material into the vacuum chamber, and control the first drive component to drive the motion platform to move along the first direction or / and the third direction. The controller 3 controls the first motor 71, the second motor 91, the filling pump 6, and the vacuum pump 2 to achieve unified and coordinated operation of the entire microneedle casting system. This embodiment has no particular restrictions on the specific type of the controller 3, and the controller may be a central processing unit (CPU), or other general-purpose processors, digital signal processors 301 (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc. The processor is the control center of the electronic device, and uses various interfaces and lines to connect various parts of the entire electronic device.

[0079] The present invention also provides a method for preparing microneedles. The method uses the above-mentioned microneedle casting system and comprises the following steps:

[0080] S1: placing the microneedle casting mold 14 on the moving platform 8, closing the vacuum chamber 1, and evacuating the vacuum chamber 1 and maintaining the vacuum state;

[0081] S2: the second driving component drives the filling needle assembly to move to a specified position, and fills the filling needle rod 11-4 with liquid, and at the same time the motion platform drives the microneedle casting mold to move along the first direction and / or the third direction. When the microneedle casting mold 14 is cast, the filling is stopped, and the motion platform 8 and the filling needle assembly 11 are reset to the initial position;

[0082] S3: restoring the vacuum chamber 1 to normal pressure, opening the chamber door of the vacuum chamber 1, and taking out the filled microneedle casting mold 14.

[0083] Specifically, when using the above-mentioned device, the operator sets the process parameters through the user interface of the display 4, and then adds the configuration raw materials of the microneedle to the mixing tank 5. After the mixing is completed, the microneedle casting mold 14 is placed on the motion platform 8, and the chamber door of the vacuum chamber 1 is closed. Click on the display 4 to start the casting program, the vacuum valve 12 opens, and the vacuum pump 2 evacuates the vacuum chamber 1. When the vacuum gauge 10 detects that the vacuum value of the vacuum chamber 1 reaches the first set value, the vacuum pump 2 stops working, and the vacuum valve 12 automatically closes to maintain the vacuum state of the vacuum chamber 1. Then the second motion component 9 drives the filling needle assembly 11 to move to the specified position, the filling pump 6 starts to fill the liquid, and the motion platform 8 drives the microneedle casting mold 14 to move. Preferably, when the vacuum gauge 10 detects that the vacuum value of the vacuum chamber 1 is lower than the second set value, the vacuum valve 12 opens, and the vacuum pump 2 evacuates the vacuum chamber 1 until the vacuum degree of the vacuum chamber 1 reaches the first set value. After the microneedle casting mold 14 is cast, the filling pump 6 stops working, and the motion platform 8 and the filling needle assembly 11 return to their initial positions. Subsequently, the vacuum venting valve 13 is opened, the vacuum chamber 1 returns to normal pressure, the chamber door of the vacuum chamber 1 is opened, and the filled microneedle casting mold 14 is taken out to complete the single casting task. For batch operation, the above process can be repeated.

[0084] Therefore, the microneedle casting system provided by the present invention can quickly complete the uniform casting of a large flat mold under high vacuum, realize high-precision and rapid replication of micro-nanoscale structures, use less casting solution, and have high casting efficiency. It has at least the following advantages:

[0085] The microneedle casting system is provided with a mixing tank, which can continuously feed materials to the filling pump to complete continuous batch casting; the end of the filling pump is connected to the filling needle assembly inserted into the vacuum chamber, and the filling needle assembly can have functions such as vacuum drip prevention and liquid discharge pressure reduction to achieve accurate filling under high vacuum conditions; the end of the filling needle rod is connected to a flat-mouthed liquid outlet head, and the wide liquid outlet can continuously spray liquid in a wide range. In conjunction with the motion platform for placing the microneedle casting mold, the plane of the microneedle casting mold can be evenly laid under different filling volumes; the vacuum chamber is connected to a vacuum pump and a vacuum gauge, and the vacuum chamber can be evacuated before or during solution filling to maintain a high negative pressure state in the vacuum chamber, so that the casting solution flows into the micro-nano structure under the surface of the microneedle casting mold, removes residual gas in the micro-nano structure, and ensures the replication accuracy of the microneedle casting mold. The entire casting process is controlled by the control system as a whole, with less liquid and high efficiency.

[0086] Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make some modifications and improvements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be based on the definition of the claims.

Claims

1. A microneedle gating system, characterized in that: include: A vacuum chamber, a motion platform, a first motion assembly, a filling needle assembly, a second motion assembly and a controller; The motion platform is arranged in the vacuum chamber and is used to support the microneedle casting mold; The first motion assembly includes a first transmission component and a first driving component connected to each other, the motion platform is connected to the first transmission component, and the first transmission component drives the motion platform to move along the first direction or / and the third direction under the drive of the first driving component; The filling needle assembly is used to transport the casting solution for preparing microneedles into the vacuum chamber. The filling needle assembly includes a liquid outlet head and a filling needle rod. One end of the filling needle rod extends into the vacuum chamber and is connected to the liquid outlet head. The second motion assembly includes a second transmission component and a second driving component connected to each other, the filling needle rod is connected to the second transmission component, and the second transmission component drives the filling needle assembly to move along the second direction under the drive of the second driving component; The controller is in communication with the first driving component and the second driving component, respectively. The controller is configured to, when the vacuum chamber is in a vacuum condition, control the second driving component to drive the filling needle assembly to approach the motion platform along the second direction, control the filling needle assembly to output a casting solution for preparing the microneedles, and control the first driving component to drive the motion platform to move along the first direction and / or the third direction; Wherein: the first direction, the second direction and the third direction are perpendicular to each other.

2. The microneedle gating system according to claim 1, characterized in that: The first driving component is a first motor, which has an output end, and the output end of the first motor is connected to the first transmission component; the first transmission component includes a support frame, a guide rod, a first screw and a moving part, the first screw is rotatably arranged on the support frame along a first direction, the guide rod is arranged along the first direction, and the guide rod is passed through the moving part, the moving part is threadedly connected to the first screw, and moves along the first direction under the action of the guide rod and the first screw, and the motion platform is fixedly connected to the moving part.

3. The microneedle gating system according to claim 2, characterized in that: The first driving component is located outside the vacuum chamber, and the first transmission component is located inside the vacuum chamber. The first driving component and the first transmission component are connected via a connecting mechanism; the connecting mechanism comprises a connecting shaft, a first coupling and a second coupling, one end of the connecting shaft is connected to the output end of the first motor via the first coupling, the other end of the connecting shaft passes through the side wall and the support frame of the vacuum chamber, and is connected to the first screw via the second coupling, and the connecting shaft seal is rotatably arranged on the side wall of the vacuum chamber between the first driving component and the first transmission component.

4. The microneedle gating system according to claim 1, characterized in that: The first driving component is a first motor, which has an output end, and the output end of the first motor is connected to the first transmission component; the first transmission component includes a support frame, a second screw, a third screw and a moving part, the second screw and the third screw are rotatably arranged on the support frame along a first direction, the moving part is moved along the first direction by threaded connection with the second screw and the third screw, and the motion platform is fixedly connected to the moving part.

5. The microneedle gating system according to claim 4, characterized in that: The second screw has a second thread threadedly connected to the moving member, the third screw has a third thread threadedly connected to the moving member, the second screw and the third screw are driven to rotate in the same direction, and the second thread and the third thread have the same pitch and the same thread direction; or, The second screw and the third screw are driven to rotate in opposite directions, and the second thread and the third thread have the same pitch and opposite thread directions.

6. The microneedle gating system according to claim 4, characterized in that: The first driving component is located outside the vacuum chamber, and the first transmission component is located inside the vacuum chamber. The first driving component and the first transmission component are connected via a connecting mechanism, and the connecting mechanism includes a connecting shaft and a connecting gear set. One end of the connecting shaft is connected to the output shaft of the first motor, and the other end of the connecting shaft passes through a side wall of the vacuum chamber and the support frame, and is connected to the second screw and the third screw through the connecting gear set. The connecting shaft seal is rotatably arranged on the side wall of the vacuum chamber between the first driving component and the first transmission component.

7. The microneedle gating system according to claim 3 or 6, characterized in that: A bearing and a sealing ring are arranged between the connecting shaft and the side wall of the vacuum chamber located between the first driving component and the first transmission component, so that the connecting shaft seal can be rotatably arranged on the side wall of the vacuum chamber located between the first driving component and the first transmission component.

8. The microneedle gating system according to claim 1, characterized in that: The second driving component is a second motor, and the second transmission component includes a column, a slide rail and a slider. The column is fixedly arranged outside the vacuum chamber, and the slide rail is arranged on the column along the second direction. One side of the slider is movably connected to the slide rail, and the other side of the slider is fixedly connected to the filling needle rod. When driven by the second motor, the slide rail drives the filling needle assembly to move along the second direction.

9. The microneedle gating system according to claim 1, characterized in that: The filling needle assembly also includes a pressure reducing valve, which is arranged in the filling needle rod and is used to achieve one or more functions of pressure reduction, pressure stabilization, and back suction of the pouring solution.

10. The microneedle gating system according to claim 9, characterized in that: The pressure reducing valve is located at the end of the filling needle rod close to the liquid outlet head, and the pressure reducing valve is provided with an external thread for threaded connection with the filling needle rod, and the end of the filling needle rod close to the liquid outlet head is provided with an external thread for threaded connection with the liquid outlet head.

11. The microneedle gating system according to claim 9, characterized in that: The valve body comprises a valve body, an inner cavity is formed in the valve body, a first slide valve and a second slide valve can be arranged in the inner cavity along the axial direction, the first slide valve and the second slide valve can move relative to the inner cavity, an inflow channel, an inflow hole, an outflow hole and an outflow channel are arranged on the valve body, the inflow channel and the outflow channel are blind holes, and the inflow channel and the outflow channel are extended along the axial direction on the valve body; The inflow channel is connected to the inner cavity through the inflow hole, the outflow channel is connected to the inner cavity through the outflow hole, and the inner cavity is divided into a first chamber, a cavity channel and a second chamber in sequence according to the positions of the inflow hole and the outflow hole; The first sliding valve is configured to: in an initial state, be subjected to a first elastic force, be maintained in a first position, and abut against the inflow hole to block the communication between the cavity channel and the inflow channel; when subjected to a first axial pressure of a casting solution greater than the first elastic force, overcome the first elastic force and move in an axial direction from the first position to the first chamber to enable communication between the cavity channel and the inflow channel; The second sliding valve is configured as follows: in an initial state, under the action of a second elastic force, it is maintained in a second position to block the connection between the cavity channel between the first sliding valve and the second sliding valve and the outflow channel; when subjected to a second axial pressure of the casting solution greater than the second elastic force, it overcomes the second elastic force and moves along the axial direction of the inner cavity from the second position to the second chamber, so that the cavity channel between the first sliding valve and the second sliding valve is connected to the outflow channel.

12. The microneedle gating system according to claim 11, characterized in that: The first sliding valve is further configured to return to the first position under the action of the first elastic force when subjected to a first axial pressure of the casting solution that is less than the first elastic force or when no longer subjected to the first axial pressure of the casting solution; The second sliding valve is further configured to return to the second position under the action of the second elastic force when subjected to a second axial pressure of the casting solution that is less than the second elastic force or when no longer subjected to the second axial pressure of the casting solution.

13. The microneedle gating system according to claim 11, characterized in that: A damping hole is also provided on the cavity wall of the first cavity, and the outflow channel and the first cavity are communicated through the damping hole.

14. The microneedle gating system according to claim 11, characterized in that: The pressure reducing valve further comprises a first fixing member and a second fixing member, the inner cavity has a third end and a fourth end, the first fixing member is fixed to the end of the third end of the inner cavity, and the second fixing member is fixed to the end of the fourth end of the inner cavity; A first elastic structure is disposed in the first chamber for providing the first elastic force, one end of the first elastic structure abuts against the first sliding valve, and the other end of the first elastic structure abuts against the first fixing member; The second chamber is provided with a second elastic structure for providing the second elastic force, one end of the second elastic structure abuts against the second sliding valve, and the other end of the second elastic structure abuts against the second fixing member.

15. The microneedle gating system according to claim 14, characterized in that: The first sliding valve includes a first sliding valve body, the first sliding valve body is provided with a hollow first stop column along the axial extension in the first chamber, and the first elastic structure is placed in the first stop column; the second sliding valve includes a second sliding valve body, the second sliding valve body is provided with a hollow second stop column along the axial extension in the second chamber, and the second elastic structure is placed in the second stop column.

16. The microneedle gating system according to claim 15, characterized in that: The first fixing member is further provided with a first groove, and the first groove is used to accommodate the first blocking column; the second fixing member is further provided with a second groove, and the second groove is used to accommodate the second blocking column.

17. The microneedle gating system according to claim 16, characterized in that: The first groove extends toward the first sliding valve to form a first protrusion, and the other end of the first elastic structure is sleeved outside the first protrusion; the second groove extends toward the second sliding valve to form a second protrusion, and the other end of the second elastic structure is sleeved outside the second protrusion.

18. The microneedle gating system according to claim 17, characterized in that: A damping hole is also provided on the cavity wall of the first cavity, and the outflow channel and the first cavity are connected through the damping hole; The distance between the damping hole and the first position is greater than the distance between the open end of the first stop column and the bottom of the first groove.

19. The microneedle gating system according to claim 11, characterized in that: The valve body is provided with a first valve seat and a second valve seat. The first valve seat is used to keep the first sliding valve in a first position to prevent the first sliding valve from approaching the second sliding valve. The second valve seat is used to keep the second sliding valve in a second position to prevent the second sliding valve from approaching the first sliding valve.

20. The microneedle gating system according to claim 11, characterized in that: The valve body is also provided with a back-suction hole, the outflow channel is communicated with the inner cavity through the back-suction hole, and the back-suction hole is located between the outflow hole and the outlet of the outflow channel.

21. The microneedle gating system according to claim 20, characterized in that: The first sliding valve is a piston, the second sliding valve is a diaphragm, and the piston has an inclined surface for causing the casting solution to generate a first axial pressure of the casting solution on the piston.

22. The microneedle gating system according to claim 1, characterized in that: The filling needle assembly further includes a filling pump, one end of the filling needle rod away from the end of the liquid outlet head is connected to the filling pump, and the filling pump is in communication connection with the controller.

23. The microneedle gating system according to claim 22, characterized in that: It also includes a mixing tank, which is connected to the filling pump and is used to evenly mix various raw materials for preparing microneedles to form a casting solution for preparing microneedles.

24. The microneedle gating system of claim 22, wherein: The other end of the filling needle rod is connected to a pressure relief valve, and the pressure relief valve is respectively connected to the filling needle rod and the filling pump through a hose, so as to discharge the liquid pressure in the filling needle rod.

25. The microneedle gating system according to claim 1, characterized in that: It comprises a vacuum valve and a vacuum pump. The vacuum valve is connected to the vacuum chamber. The vacuum pump acts on the vacuum chamber through the vacuum valve to maintain a negative pressure state in the vacuum chamber.

26. The microneedle gating system according to claim 1, characterized in that: It includes a vacuum deflation valve, which is arranged in the vacuum chamber and is used to break the vacuum in the vacuum chamber.

27. The microneedle gating system according to claim 1, characterized in that: The vacuum chamber is connected to a vacuum gauge, and the vacuum gauge is in communication with the controller to obtain the vacuum condition of the vacuum chamber.

28. The microneedle gating system of claim 1, wherein: A display is included, which is communicatively connected to the controller to display the status of the system.

29. A method for preparing a microneedle, characterized in that: The microneedle gating system according to any one of claims 1 to 28 comprises the following steps: S1: placing the microneedle casting mold on the moving platform, closing the vacuum chamber, and evacuating the vacuum chamber and maintaining the vacuum state; S2: the second driving component drives the filling needle assembly to move along the second direction to a specified position, and fills the filling needle assembly with liquid, and at the same time, the motion platform drives the microneedle casting mold to move along the first direction and / or the third direction, and stops filling the microneedle casting mold when casting is completed; S3: restoring the vacuum chamber to normal pressure, opening the chamber door of the vacuum chamber, and taking out the filled microneedle casting mold.

30. The method for preparing a microneedle according to claim 29, wherein: The microneedle casting system includes a display connected to the controller, a filling pump connected to the filling needle rod, a mixing tank connected to the filling pump, a vacuum valve and a vacuum gauge connected to the vacuum chamber, a vacuum pump and a vacuum venting valve connected to the vacuum valve, and the filling pump, the vacuum gauge, the vacuum pump, the vacuum venting valve, and the vacuum valve are all connected to the controller, and include the following steps: S11: setting process parameters on the display, adding solution-configured raw materials into the mixing tank, placing the microneedle casting mold on the motion platform after the mixing is completed, and closing the vacuum chamber; S21: Click on the display to start the pouring procedure, open the vacuum valve, and use the vacuum pump to evacuate the vacuum chamber; S31: When the vacuum gauge detects that the vacuum value of the vacuum chamber reaches a first set value, the vacuum pump stops working and the vacuum valve is closed to maintain the vacuum state in the vacuum chamber; S41: the second driving component drives the filling needle assembly to move along the second direction to a specified position, the filling pump starts to fill the filling needle assembly with liquid, and at the same time the motion platform drives the microneedle casting mold to move along the first direction and / or the third direction. When the casting of the microneedle casting mold is completed, the filling pump stops working, and the motion platform and the filling needle assembly are reset to the initial position; S51: Open the vacuum venting valve to restore the vacuum chamber to normal pressure, open the chamber door of the vacuum chamber, and take out the filled microneedle casting mold.

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