A microfluidic valve

Abstract

This invention relates to the fields of medical devices and precision fluid control technology, specifically a miniature fluid valve, comprising a base and a valve body movably disposed within the base. The base has a first groove and a second groove on each side. This miniature fluid valve is adaptable to the installation and use of microfluidic devices and various miniature medical devices. The valve body is guided by a spring in conjunction with the first and second grooves on the base, ensuring smooth and non-jamming movement. The addition of a circular pin and stop limit structure further enhances stable and reliable operation. The sealing structure, employing an elastic diaphragm, a sphere, and a sealing ring, minimizes reverse leakage and enables unidirectional fluid flow, preventing backflow. Finally, all sealing components are made of medical-grade materials, ensuring safe contact with medications and other fluids. The valve is simple to assemble, performs stably, and effectively meets the practical needs of miniature fluid control applications.

Description

Technical Field

[0001] This invention relates to the fields of medical devices and precision fluid control technology, specifically a miniature fluid valve. Background Technology

[0002] Current medical technology is rapidly developing towards precision, miniaturization, and implantability. New medical devices such as microfluidic chips, implantable drug delivery devices, and in vitro diagnostic equipment have placed unprecedentedly stringent requirements on the size, sealing, and biosafety of fluid control components. As a core component for controlling the directional delivery of medical fluids, the miniature one-way fluid valve directly determines the delivery accuracy and safety of the equipment and is a key link in the industry's technological breakthroughs.

[0003] Traditional fluid valves, limited by structural design and manufacturing processes, generally suffer from drawbacks such as large size, poor sealing performance, and insufficient reliability, making them unsuitable for the application requirements of medical miniaturization scenarios. Existing miniaturized valve products either have a size that is difficult to control to within 3mm. 3 Within this range, either the reverse leakage rate far exceeds 0.1%, which can easily cause fluid backflow, reagent waste, or dosing errors, seriously affecting diagnostic accuracy and treatment safety. At the same time, most conventional valves use non-medical grade materials, and their biocompatibility does not meet the ISO10993 standard. They cannot directly contact blood, drugs, or other human-related fluids, which limits their use in implantable and minimally invasive medical devices.

[0004] With the continuous upgrading of regulations on the safety and reliability of medical devices under the Medical Device Supervision and Management Regulations, and the rapid iteration of microfluidics and biodegradable implantable technologies, the market urgently needs a unidirectional fluid valve that combines ultra-miniature size, low reverse leakage, high biocompatibility, and multi-fluid adaptability. However, there is currently no mature solution in the industry that can simultaneously meet all of the above indicators. Existing technological shortcomings have become the core bottleneck restricting the precision of in vitro diagnostic equipment and the industrialization of implantable medical devices. To solve the above industry pain points and break through the technical barriers of microfluidic control, developing a high-performance microfluidic valve that meets clinical medical requirements is of great practical significance for promoting the upgrading of medical technology and ensuring the safety of clinical use. Summary of the Invention

[0005] To overcome the problems of existing microfluidic valves, such as large size, poor sealing, high leakage, and insufficient biocompatibility, this invention provides a microfluidic valve with miniaturization, high sealing, low leakage, biocompatibility, and unidirectional controllability.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a miniature fluid valve, comprising a base, wherein a first groove and a second groove are respectively formed on both sides of the base; a stop block is disposed on one side of the base; a valve body is disposed inside the base, and a fluid inlet and a fluid outlet are respectively formed on both sides of the valve body; the valve body is a one-way fluid valve, and fluid can only flow from the fluid inlet to the fluid outlet, thus the one-way conduction characteristic can precisely control the fluid direction, meeting the usage requirements of medical devices; a sealing ring is disposed inside the valve body; and a sphere is disposed inside the valve body. The valve body comprises an elastic diaphragm disposed between the valve body and the valve cover, a valve cover bonded to one side of the valve body, a circular pin disposed in the middle of the valve cover, and a spring, one end of which is disposed on the inner wall of the first slide groove, and the other end of which is fixedly disposed with the valve body. The valve body can slide along the first slide groove and the second slide groove. The circular pin forms a limiting fit with the stop block. When there is no external thrust, the spring drives the valve body to abut against the stop block, and the circular pin squeezes the elastic diaphragm and presses the ball. The ball and the sealing ring form a seal. When the external thrust is greater than the spring force, the seal is released, and the fluid flows from the fluid inlet to the fluid outlet.

[0007] Preferably, the valve cover and valve body are fixed together by adhesive. This bonding method can strengthen the connection between the valve cover and valve body, while ensuring the sealing performance at the joint.

[0008] Preferably, the overall volume of the valve body and valve cover is less than 3mm. 3 The small size allows the valve body to be adapted to miniaturized installation scenarios such as microfluidic chips and implantable medical devices.

[0009] Preferably, the elastic diaphragm is pressed tightly against the valve body by the valve cover, and the elastic diaphragm and the sealing ring are made of the same material.

[0010] Preferably, the sealing ring is made of a medical biocompatible material that conforms to ISO10993 standards. This material can directly contact human fluids such as blood and medicines, thus meeting the biosafety requirements of medical devices.

[0011] Preferably, the sphere is a medical-grade rigid sphere, which can stably fit with the sealing ring to ensure the sealing reliability of the valve in the closed state.

[0012] Preferably, the first groove on the base is used for positioning and guiding the spring, and the second groove is used for sliding guidance of the valve body.

[0013] Preferably, the base, the first slide groove, the second slide groove, and the stop are integrally formed.

[0014] Beneficial effects: This miniature fluid valve is compatible with microfluidic devices and various micro-medical devices. The valve body is guided by a spring in conjunction with the first and second slide grooves on the base, ensuring smooth and non-jamming movement. The use of a circular pin and stop block for limiting the position ensures stable and reliable operation. Furthermore, the sealing structure, combining an elastic diaphragm, a ball, and a sealing ring, minimizes reverse leakage and enables unidirectional fluid flow, preventing backflow. Finally, all sealing components are made of medical-grade materials with excellent biocompatibility, allowing safe contact with medications and other fluids. The valve is simple to assemble, performs stably, and effectively meets the practical needs of microfluidic control. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 for Figure 1 Cross-sectional view of the valve body of BB in the open state; Figure 3 for Figure 1 Cross-sectional view of the valve body of BB in the closed state.

[0016] In the diagram: 1. Valve body; 2. Spring; 3. First slide groove; 4. Sealing ring; 5. Ball; 6. Elastic diaphragm; 7. Circular pin; 8. Stop block; 9. Valve cover; 10. Second slide groove; 11. Fluid inlet; 12. Fluid outlet; 13. Base. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0019] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0020] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0021] See Figures 1-3 A miniature fluid valve includes a base 13 and a valve body 1 movably disposed inside the base 13. A first groove 3 and a second groove 10 are respectively provided on both sides of the base 13. A stop block 8 is provided on one side of the base 13. A valve cover 9 is bonded to one side of the valve body 1, and an elastic diaphragm 6 is provided between the valve cover 9 and the valve body 1. A circular pin 7 is provided in the middle of the valve cover 9. A ball 5 and a sealing ring 4 are provided inside the valve body 1. A spring 2 is provided on the inner wall of the first groove 3, and one end of the spring 2 is fixedly connected to the valve body 1.

[0022] This device is mainly used in scenarios with high requirements for fluid control precision, structural size, and biosafety, such as microfluidic chips, in vitro diagnostic equipment, micro-drug delivery devices, and implantable medical devices. The whole device adopts a pure mechanical structure design, which does not require electrical drive. It relies on spring reset and mechanical limit to realize the opening and closing of the valve and unidirectional conduction. While ensuring miniaturization, it has excellent sealing performance and operational stability.

[0023] The base 13, serving as the load-bearing and guiding foundation of the entire valve, is manufactured using an integrated molding process. Its material is engineering plastic with sufficient structural strength and resistance to medical fluid corrosion. The integrated molding design effectively avoids assembly errors caused by split structures, reduces the number of parts, simplifies the overall assembly process, and enhances the integrity and durability of the valve structure. The first slide groove 3 and the second slide groove 10 are symmetrically arranged along the length of the base 13, and the inner walls of the slide grooves are finely polished, with surface roughness controlled to a low range. This effectively reduces frictional resistance during component sliding, preventing jamming or sticking. The stop block 8 and the base 13 are of the same material and are integrated, primarily used to limit the sliding stroke of the valve body 1, preventing the valve body 1 from sliding out of the installation range of the base 13 under spring thrust. Simultaneously, it works with the circular pin 7 to achieve positioning constraint when the valve is closed.

[0024] The external dimensions of the valve body 1 are adapted to the internal cavity of the base 13, ensuring that the valve body 1 can slide smoothly within the base without radial wobbling. As the core carrier for fluid flow, the valve body 1 has a fluid inlet 11 and a fluid outlet 12 on its two sides, respectively. The fluid inlet 11 and the fluid outlet 12 are coaxially arranged, and the orifice diameter is customized according to the flow requirements of micro fluid delivery. This can meet the delivery requirements of conventional medical fluids without causing the overall valve size to exceed the standard due to excessively large orifice diameter. The sealing ring 4 is made of medical-grade biocompatible elastic material, and its shape matches the internal cavity of the valve body 1. After installation, it fits tightly against the inner wall of the valve body 1.

[0025] The sphere 5 is a medical-grade rigid sphere made of medical stainless steel or medical ceramic. It has the characteristics of high hardness, smooth surface, resistance to acid and alkali corrosion, and no reaction with the drug solution. The diameter of the sphere 5 is matched with the inner diameter of the sealing ring 4, which can form a tight surface seal with the sealing ring 4 under the compression of the elastic film, blocking the flow path of the fluid.

[0026] The elastic membrane 6 also uses medical biocompatible elastic material, which has good deformation and reset capabilities. Its edge area is tightly pressed and fixed to the end face of the valve body 1 by the valve cover 9. The valve cover 9 and the valve body 1 are bonded and fixed with medical adhesive. The adhesive is evenly applied to the bonding surface, which not only ensures the connection strength between the two and prevents them from falling off or separating during long-term use, but also ensures the sealing performance of the joint and prevents fluid from leaking from the bonding gap.

[0027] The circular pin 7 and the valve cover 9 are installed with an interference fit, and their ends are set towards the elastic diaphragm 6. The ends of the circular pin 7 are rounded to avoid scratching the elastic diaphragm 6 during the compression process, which would affect the sealing effect and service life.

[0028] Spring 2 is a compression spring made of medical-grade stainless steel, which has good elasticity and fatigue resistance. It will not experience elastic decay or breakage after long-term repetitive use. One end of spring 2 is fixedly connected to the inner wall of the first slide groove 3, and the other end is fixedly connected to the end of the valve body 1.

[0029] In the absence of external force, spring 2 is in its initial extended state. Under the elastic thrust of spring 2, valve body 1 slides along the first slide groove 3 and the second slide groove 10 toward the stop block 8 until valve body 1 abuts against the stop block 8. At this time, the end of the circular pin 7 in the middle of valve cover 9 tightly squeezes the elastic film 6. The elastic film 6 deforms under force, and then presses the ball 5 into the inside of valve body 1, so that the ball 5 is tightly attached to the surface of the sealing ring 4, forming a complete sealing structure, blocking the flow channel between fluid inlet 11 and fluid outlet 12. The valve is in a stable closed state, and the fluid cannot flow from the inlet to the outlet. The reverse leakage rate is controlled at an extremely low level, effectively avoiding the problem of medical fluid backflow and leakage, and meeting the stringent requirements for sealing performance in medical scenarios.

[0030] When fluid needs to be channeled, an external thrust is applied to the valve body 1 toward the side of the spring 2. When the magnitude of the external thrust is greater than the elastic force of the spring 2, the valve body 1 will overcome the elastic force of the spring 2 and slide along the first slide groove 3 and the second slide groove 10 in the direction of spring 2 contraction. At this time, the circular pin 7 moves synchronously with the valve body 1, gradually releasing the squeezing force on the elastic diaphragm 6. The elastic diaphragm 6 resets under its own elastic action and no longer presses the ball 5. The sealing fit between the ball 5 and the sealing ring 4 is released, and a smooth flow channel is formed between the fluid inlet 11 and the fluid outlet 12. The medical fluid can enter the interior of the valve body 1 from the fluid inlet 11, and flow out from the fluid outlet 12 after passing through the sealing gap, realizing the directional delivery of the fluid.

[0031] When the external thrust is removed, the valve body 1 is no longer constrained by external force. The spring 2 will quickly release its elastic potential energy, pushing the valve body 1 to slide in the opposite direction along the slide groove and reset back towards the stop block 8. The circular pin 7 will squeeze the elastic diaphragm 6 again, so that the ball 5 and the sealing ring 4 will resume their sealing fit. The valve will quickly return to the closed state. The entire reset process is responsive and requires no additional drive components. The purely mechanical structure design makes the valve operation more reliable and will not cause opening and closing failures due to electrical faults.

[0032] Meanwhile, the overall volume of the device is controlled within 3mm. 3 Its extremely miniaturized size allows it to be easily adapted to devices with limited space, such as microfluidic chips and micro diagnostic instruments, solving the problem that traditional fluid valves are too large to be used in micro medical devices.

[0033] This miniature fluid valve is compatible with microfluidic devices and various micro-medical devices. The valve body 1 is guided by a spring 2 in conjunction with the first and second slide grooves 3 and 10 on the base 13, ensuring smooth and stable movement without jamming. The limiting structure of the circular pin 7 and the stop block 8 ensures stable and reliable operation. The sealing structure, which combines an elastic diaphragm 6, a ball 5, and a sealing ring 4, minimizes reverse leakage and enables unidirectional fluid flow, preventing backflow. Finally, all sealing components are made of medical-grade materials with good biocompatibility, allowing safe contact with medications and other fluids. The valve is simple to assemble, has stable performance, and effectively meets the practical needs of microfluidic control.

[0034] Working principle: In use, under normal conditions without external force, the spring 2 in the first groove 3 of the base 13 is in an extended state, continuously applying a pushing force to the valve body 1. This causes the valve body 1 to slide along the first groove 3 and the second groove 10 towards the stop block 8 and press against the limit position. At this time, the circular pin 7 in the middle of the valve cover 9 tightly presses the elastic film 6 between the valve body 1 and the valve cover 9, causing the elastic film 6 to press inward against the ball 5 inside the valve body 1. The ball 5 and the sealing ring 4 fit tightly together to form a sealed barrier, blocking the passage between the fluid inlet 11 and the fluid outlet 12. The valve remains closed, effectively preventing fluid backflow and leakage. When fluid needs to be transported, an external thrust is applied to the valve body 1 towards the spring 2. When the thrust exceeds the spring force of the spring 2, the valve body 1 moves along the groove towards the contraction direction of the spring 2. The circular pin 7 moves synchronously with the valve body 1 and no longer applies pressure to the elastic diaphragm 6. The elastic diaphragm 6 resets itself due to its own elasticity, releasing the pressure on the ball 5. A flow gap is formed between the ball 5 and the sealing ring 4, allowing fluid to flow in from the fluid inlet 11 and out from the fluid outlet 12 after passing through the gap, thus achieving unidirectional fluid transport.

[0035] After the external thrust is removed, the spring 2 quickly rebounds and resets, pushing the valve body 1 to slide towards the stop block 8 again. The circular pin 7 then squeezes the elastic diaphragm 6 and presses the ball 5, and the valve quickly returns to the closed and sealed state, thus completing a complete opening and closing cycle. Stable fluid flow and unidirectional control are achieved by relying on a purely mechanical structure.

[0036] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A miniature fluid valve, characterized in that, include: The base (13) has a first groove (3) and a second groove (10) respectively on both sides. A stop (8) is provided on one side of the base (13); The valve body (1) is located inside the base (13), and fluid inlet (11) and fluid outlet (12) are respectively provided on both sides of the valve body (1). A sealing ring (4) is disposed inside the valve body (1); A sphere (5) is disposed inside the valve body (1); An elastic diaphragm (6) is disposed between the valve body (1) and the valve cover (9); Valve cover (9), which is bonded to one side of valve body (1); A circular pin (7) is provided in the middle of the valve cover (9); Spring (2), one end of which is disposed on the inner wall of the first slide groove (3), and the other end of which is fixedly disposed with the valve body (1); The valve body (1) can slide along the first slide groove (3) and the second slide groove (10). The circular pin (7) and the stop block (8) form a limiting fit. When there is no external thrust, the spring (2) drives the valve body (1) to abut against the stop block (8). The circular pin (7) squeezes the elastic film (6) and presses the ball (5). The ball (5) and the sealing ring (4) form a seal. When the external thrust is greater than the elastic force of the spring (2), the seal is released and the fluid flows from the fluid inlet (11) to the fluid outlet (12).

2. The microfluidic valve according to claim 1, characterized in that, The valve cover (9) and valve body (1) are fixed by adhesive. This adhesive method can strengthen the connection strength between the valve cover (9) and valve body (1) and ensure the sealing performance at the joint.

3. The microfluidic valve according to claim 1, characterized in that, The overall volume of the valve body (1) and valve cover (9) is less than 3 mm. 3 The small size allows the valve body (1) to be adapted to miniaturized installation scenarios such as microfluidic chips and implantable medical devices.

4. The microfluidic valve according to claim 1, characterized in that, The elastic diaphragm (6) is pressed tightly onto the valve body (1) by the valve cover (9), and the elastic diaphragm (6) and the sealing ring (4) are made of the same material.

5. The microfluidic valve according to claim 1, characterized in that, The sealing ring (4) is made of a standard medical biocompatible material that can directly contact human fluids such as blood and medicine, and meets the biosafety requirements of medical devices.

6. The microfluidic valve according to claim 1, characterized in that, The sphere (5) is a medical-grade rigid sphere. The rigid sphere can fit stably with the sealing ring to ensure the sealing reliability of the valve in the closed state.

7. The microfluidic valve according to claim 1, characterized in that, The first groove (3) on the base (13) is used for positioning and guiding the spring (2), and the second groove (10) is used for sliding guidance of the valve body (1).

8. The microfluidic valve according to claim 1, characterized in that, The base (13), the first slide groove (3), the second slide groove (10) and the stop (8) are integrally formed structures.

9. The microfluidic valve according to claim 1, characterized in that, The valve body (1) is a one-way fluid valve, and the fluid can only flow from the fluid inlet (11) to the fluid outlet (12). Therefore, the one-way conduction characteristic can accurately control the fluid direction and meet the needs of medical equipment.

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