Miniature valve and piezoelectric pump

Abstract

This invention discloses a miniature valve and a piezoelectric pump, comprising: a first valve body with a fluid inlet; and a valve disc connected to the first valve body, wherein a guide hole is formed on the valve disc. The valve disc is responsive to a pressure difference between the pressure on the side of the fluid inlet away from the valve disc and the pressure on the side of the guide hole away from the first valve body, causing it to bend and deform, thereby changing the relative position between the valve disc and the first valve body, thus opening or closing the fluid passage through the guide hole. This invention uses a double-layer structure to form the smallest valve unit, utilizes pressure difference to achieve valve opening and closing, and the double-layer structure can be bonded together in one step, offering high assembly tolerance and reliable sealing.

Description

Technical Field

[0001] This invention relates to the field of fluid control technology, and more particularly to a miniature valve and a piezoelectric pump. Background Technology

[0002] As the core control element of microfluidic systems, microfluidic valves are widely used in precision instruments such as biochips, MEMS sensing (Micro-Electro-Mechanical Systems) and drug infusion systems.

[0003] For example, the "improved valve" with the existing patent publication number GB2616883A is a miniature fluid valve mainly composed of a four-layer structure. Although it can achieve basic flow control functions, the multi-layer assembly requires precise positioning. At the microscale, misalignment is prone to occur, reducing the production qualification rate. There are many sealing interfaces between the layers, which increases the risk of leakage, and misalignment of the flow channel is more likely to cause abnormal increase in flow resistance.

[0004] The elastic diaphragm is responsible for the core opening and closing function of the valve. Under frequent deformation, collision and friction, it faces fatigue failure problems, mainly manifested as microcrack propagation and springback nonlinearity in the stress concentration area, which directly affects the long-term reliability of the valve body and the accuracy of micro-flow control.

[0005] However, the miniaturization of fluid valves forces the support structure to be weakened, which leads to a contradiction between unidirectional cutoff and flow resistance characteristics. Miniaturization is often accompanied by a decrease in cutoff and a reduction in the cross-sectional area of ​​the flow channel, which ultimately leads to an increase in leakage rate and a surge in energy consumption.

[0006] Therefore, existing improvement solutions either rely on redundant structures at the expense of compactness, or use thickened diaphragms to reduce dynamic response. Seeking a miniaturized, simple, and long-life valve structure is the key to improving performance and achieving widespread application. Summary of the Invention

[0007] The purpose of this invention is to provide a miniature valve and a piezoelectric pump, which form the smallest valve unit through a double-layer structure, and realize the opening and closing of the valve by utilizing pressure difference. Furthermore, the double-layer structure can be bonded together in one step, with large assembly tolerance and reliable sealing.

[0008] The objective of this invention is achieved through the following technical solution:

[0009] A miniature valve, comprising:

[0010] The first valve body is equipped with a fluid inlet;

[0011] A valve disc is connected to the first valve body, and a flow guide hole is provided on the valve disc;

[0012] The valve disc can elastically deform in response to the pressure difference between the pressure on the side of the fluid inlet away from the valve disc and the pressure on the side of the guide hole away from the first valve body, thereby changing the relative position between the valve disc and the first valve body, so that the fluid passage flowing through the guide hole is opened or closed.

[0013] Preferably, the elastic deformation of the valve disc includes:

[0014] When the pressure on the side of the fluid inlet away from the valve disc is greater than the pressure on the side of the guide hole away from the first valve body, the valve disc bends and deforms in the direction away from the first valve body, so that the fluid can flow out through the guide hole.

[0015] When the pressure on the side of the fluid inlet away from the valve disc is less than the pressure on the side of the guide hole away from the first valve body, the valve disc bends and deforms toward the direction closer to the first valve body to seal the area where the fluid inlet is located.

[0016] Preferably, it further includes:

[0017] The second valve body is located on one side of the valve disc and is disposed opposite to the first valve body, and is provided with a fluid outlet;

[0018] A constraint structure is disposed on the surface of the second valve body relative to the first valve body and / or between the first valve body and the valve disc, the constraint structure being used to abut against the deformed portion of the valve disc for support.

[0019] Preferably, the second valve body includes a valve plate, the valve plate being provided with a protrusion, and at least one outlet hole and at least one spacer hole being formed around the protrusion as the fluid outlet;

[0020] The outlet hole may or may not intersect with the spacer hole.

[0021] Preferably, the constraint structure includes a limiting ring, which is integrally formed with or separately connected to the surface of the valve plate;

[0022] The limiting ring has a through portion for accommodating the portion of the valve disc that bulges toward the direction of the second valve body.

[0023] Preferably, the height of the through portion is greater than or equal to the height of the protrusion, which is used to limit the maximum displacement of the valve disc when it deforms toward the second valve body.

[0024] Preferably, the top of the protrusion is a flat surface or an outwardly convex arc surface.

[0025] Preferably, the projection of the outlet hole onto the valve disc at least partially overlaps with the guide hole to form a fluid passage, and the spacer hole is coaxial and collinear with the fluid inlet.

[0026] Preferably, the diameter of the valve disc is smaller than the diameter of the through portion, and the through portion around the valve disc forms an annular buffer zone.

[0027] Preferably, the constraint structure further includes a first support layer, which is disposed between the first valve body and the valve disc. The first support layer is provided with a support portion corresponding to the fluid inlet. The support portion is used to allow fluid to pass through the fluid inlet and to provide support and limit the portion of the valve disc that is deformed.

[0028] Preferably, the support portion includes at least one first support ring and a connecting beam for interconnection with the first support ring, wherein the outer diameter of the first support ring is larger than the orifice diameter of the fluid inlet.

[0029] Preferably, the valve disc surface is provided with at least one corrugated structure to guide and enhance the elastic deformation of the valve disc under pressure.

[0030] Preferably, the cross-sectional profile of the corrugated structure is wavy, including alternating upper and lower convex regions;

[0031] When the pressure on the side of the fluid inlet away from the valve disc is greater than the pressure on the side of the guide hole away from the first valve body, the upper convex area arches outward and the lower convex area is concave, moving in a direction away from the first valve body;

[0032] When the pressure on the side of the fluid inlet away from the valve disc is less than the pressure on the side of the guide hole away from the first valve body, the upper and lower convex areas fold back and move toward the direction closer to the first valve body.

[0033] Preferably, the projection of the inner edge of the upper convex area of ​​the adjacent corrugated structure onto the first valve body falls within the outline of the fluid inlet;

[0034] The projection of the outer edge of the upper convex region of the adjacent corrugated structure onto the first valve body falls outside the outline of the fluid inlet.

[0035] Preferably, the corrugated structure has a reinforcing structure at its center, which is at least one support rib provided on the upper and / or lower surfaces of the center.

[0036] Alternatively, the reinforcing structure may be a lightweight filler block that fills the upper and / or lower surfaces of the central portion.

[0037] Preferably, the support ribs are arranged in a central radial, non-central offset, or non-radial oblique pattern.

[0038] Preferably, the lightweight filler block is made of porous SiO2, hollow glass microspheres, PDMS composite or aluminosilicate foam.

[0039] Preferably, a second support layer is provided between the valve disc and the second valve body, and the projection of the second support layer on the valve disc completely covers the flow guide hole.

[0040] Preferably, the second support layer is a ring-shaped structure or a sheet-like structure;

[0041] The second support layer is made of porous sponge, aerogel or 3D mesh fiber.

[0042] Preferably, the surface of the first valve body facing the valve disc is provided with a sealing structure surrounding the fluid inlet, which is used to contact the valve disc to achieve a seal when the valve disc deforms towards the first valve body.

[0043] Preferably, the sealing structure is an annular groove surrounding the fluid inlet and recessed into the first valve body.

[0044] Preferably, the sealing structure includes a second support ring protruding from the surface of the first valve body, the second support ring forming line contact or surface contact with the valve disc.

[0045] Preferably, the second support ring includes an inner ring body and an outer ring body arranged concentrically, an annular groove is formed between the inner ring body and the outer ring body, and at least one notch for fluid flow is provided on the inner ring body or the outer ring body.

[0046] Preferably, the surface of the first valve body facing the valve disc is further provided with at least one drag-reducing structure, which is isolated from the fluid inlet and is used to support the first valve body.

[0047] A piezoelectric pump includes: at least one housing, the housing having at least one inlet and / or at least one outlet, the at least one inlet being provided with at least one inlet valve, and / or the at least one outlet being provided with at least one outlet valve;

[0048] At least one piezoelectric element is arranged opposite to the housing to form a pump chamber;

[0049] The inlet valve and outlet valve are miniature valves as described above.

[0050] Preferably, the housing is a single unit;

[0051] Alternatively, there are two housings, which are stacked opposite each other, with the piezoelectric element located between the two housings;

[0052] Alternatively, there may be multiple housings, which are stacked sequentially; there may also be multiple piezoelectric elements, which are arranged alternately with the housings.

[0053] Preferably, the piezoelectric element has at least one through hole communicating with the pump chamber, and at least one of the micro valves is installed in the at least one through hole; or, the pump chamber is not communicating with the through hole.

[0054] Compared with the prior art, the beneficial effects of the present invention include at least the following:

[0055] The pressure difference generated by the pressure on the side of the fluid inlet away from the valve disc and the pressure on the side of the guide hole away from the first valve body enables a rapid response and allows the valve to be opened or closed in one direction, making the overall structure simple and compact, with low flow resistance and high reliability.

[0056] By setting up a second valve body and a constraint structure, the deformed part of the valve disc can be limited and supported when the valve disc deforms, so as to avoid excessive deformation of the valve disc, which would affect the valve's response time. It also ensures a reliable seal and reduces the risk of misalignment between multi-layer structures. Attached Figure Description

[0057] Figure 1 This is a schematic diagram of the separation structure of the first valve body and valve disc in an embodiment of the present invention;

[0058] Figure 2 a2 is a cross-sectional view of the first valve body and valve disc connected together in an embodiment of the present invention, and b2 is a partially enlarged schematic diagram of point A in a2;

[0059] Figure 3 Figure a3 is a diagram showing the deformation of the valve disc structure in an embodiment of the present invention, and figure b3 is a partially enlarged schematic diagram of point B in figure a3.

[0060] Figure 4 Figure a4 is a diagram showing another deformation of the valve disc structure in an embodiment of the present invention, and figure b4 is a partially enlarged schematic diagram of point C in figure a4.

[0061] Figure 5 This is a schematic diagram of the separation structure of the first valve body, valve disc, and second valve body according to an embodiment of the present invention;

[0062] Figure 6 This is a schematic diagram showing the separation of the first valve body, valve disc, second valve body, and constraint structure according to an embodiment of the present invention.

[0063] Figure 7 This is an embodiment of the present invention. Figure 6A magnified view of a portion of point D in the middle;

[0064] Figure 8 A8 is a cross-sectional view of the first valve body, valve disc, second valve body, and constraint structure connected together in an embodiment of the present invention, and B8 is a partially enlarged schematic diagram of point E in A8.

[0065] Figure 9 This is an embodiment of the present invention. Figure 8 A schematic diagram of the structure in which the outlet hole and the spacer hole of B8 are integrated;

[0066] Figure 10 a10 is an embodiment of the present invention. Figure 8 The valve disc structure in b8 is deformed and the inner diameter of the first support ring is smaller than the outlet orifice diameter. b10 is... Figure 8 The diagram shows the deformation of the valve disc structure in b8 and the inner diameter of the first support ring being equal to the outlet orifice diameter, and c10 is... Figure 8 A schematic diagram showing that the valve disc structure of b8 is deformed and the inner diameter of the first support ring is larger than the diameter of the outlet hole.

[0067] Figure 11 This is an embodiment of the present invention. Figure 8 A schematic diagram showing the deformation of the valve disc structure in b8;

[0068] Figure 12 a12, b12, and c12 are schematic diagrams of different shapes of the fluid outlet of the second valve body in an embodiment of the present invention;

[0069] Figure 13 In the diagram, a13 is an integrated structure diagram of the valve plate and the limiting ring according to an embodiment of the present invention; b13 is a separate structure diagram of the valve plate and the limiting ring; c13 is a structure diagram in which the height of the protrusion is lower than the height of the through part of the limiting ring; and d13 is a schematic diagram of different structures of the protrusion.

[0070] Figure 14 A14 is a schematic diagram of the structure of the protrusion at different positions in an embodiment of the present invention, and B14 is a cross-sectional schematic diagram of A14.

[0071] Figure 15 This is a schematic diagram of a valve disc structure with a small diameter according to an embodiment of the present invention;

[0072] Figure 16 This is a schematic diagram of the corrugated structure on the valve disc according to an embodiment of the present invention;

[0073] Figure 17 This is an embodiment of the present invention. Figure 16 A magnified view of a portion at point F;

[0074] Figure 18 This is an embodiment of the present invention. Figure 17A schematic diagram of the corrugated structure supporting ribs;

[0075] Figure 19 This is an embodiment of the present invention. Figure 16 A cross-sectional view of one of the corrugated structures;

[0076] Figure 20 This is a schematic diagram showing the position of the valve disc with a corrugated structure relative to the first valve body and the second valve body, and the direction of fluid flow when the valve disc with the corrugated structure deforms according to an embodiment of the present invention.

[0077] Figure 21 a21 is a diagram of the second support layer in an embodiment of the present invention as a sheet structure, and b21 is a diagram of the second support layer as a ring structure;

[0078] Figure 22 In diagram a22, we see a structural diagram of the annular groove on the first valve body in an embodiment of the present invention, and in diagram b22, we see a partially enlarged schematic diagram of point G in a22.

[0079] Figure 23 In diagram a23, we see a structural diagram of the second support ring on the first valve body in an embodiment of the present invention, and in diagram b23, we see an enlarged structural diagram of section H of a23.

[0080] Figure 24 This is an embodiment of the present invention. Figure 23 A partially enlarged schematic diagram of another structure of b23;

[0081] Figure 25 In this embodiment of the invention, a25 is a front view of the first valve body with a drag reduction structure, b25 is a cross-sectional view of a25, and c25 is a partially enlarged schematic diagram of point I in b25.

[0082] Figure 26 This is a schematic diagram of a piezoelectric pump with a micro-valve according to some embodiments of the present invention.

[0083] Figure 27 This is a schematic diagram of a piezoelectric pump with a micro-valve in some other embodiments of the present invention.

[0084] In the diagram: 100, First valve body; 11, Fluid inlet; 111, Inflow hole; 12, Drag reduction structure; 13, Annular groove; 14, Second support ring; 141, Outer ring; 142, Inner ring; 143, Notch; 144, Annular groove; 200, Valve disc; 21, Guide hole; 22, Corrugated structure; 221, Support rib; 222, Upper convex area; 223, Lower convex area; 224, Central part; 300, Second valve body; 31, Valve plate; 32, Protrusion; 33. Fluid outlet; 332, spacer hole; 331, outlet hole; 34, outflow hole; 400, limiting ring; 41, through section; 500, first support layer; 51, support section; 511, first support ring; 512, connecting beam; 600, second support layer; 700, piezoelectric pump; 7, piezoelectric element; 71, pump chamber; 72, inlet; 721, inlet valve; 73, outlet; 731, outlet valve; 74, substrate; 75, piezoelectric wafer; 76, drive circuit; 77, through hole. Detailed Implementation

[0085] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided to make the invention more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore repeated descriptions of them will be omitted.

[0086] The terms used to express position and direction in this invention are illustrated with reference to the accompanying drawings, but changes can be made as needed, and all such changes are included within the scope of protection of this invention.

[0087] This invention provides a miniature valve, such as Figure 1 As shown, the miniature valve consists of a first valve body 100 and a valve disc 200 forming the smallest working unit.

[0088] The first valve body 100 is a thin sheet or plate structure with a preset thickness. Its main material can be monocrystalline silicon, glass, stainless steel, titanium alloy, or engineering plastics (such as PEEK, polyimide, etc.). The first valve body 100 can be manufactured through micromachining processes such as photolithography, etching, precision stamping, injection molding, or milling. A fluid inlet 11 is provided in the main body area of ​​the first valve body 100. The fluid inlet 11 can be one or more inflow holes 111 penetrating the thickness of the first valve body 100. The cross-sectional shape of the inflow hole 111 is preferably circular to facilitate uniform fluid flow and processing. The hole diameter can be set according to actual flow requirements, and multiple inflow holes 111 are evenly distributed in an array or ring. The shape of the inflow hole 111 can also be triangular, elliptical, semi-circular, trapezoidal, or polygonal.

[0089] The valve disc 200 is a flexible thin-film structure, serving as a valve plate. Its material can be polydimethylsiloxane (PDMS), polyimide (PI), silicone rubber, parylene, ultra-thin metal foil (such as beryllium copper alloy), or a polymer material with good elasticity and fatigue life. The valve disc 200 is a circular thin sheet with an overall diameter larger than the circumcircle diameter of the distribution area of ​​all inflow holes 111. This ensures that the orthographic projection of the valve disc 200 on the first valve body 100 completely covers all inflow holes 111, and the boundary of the valve disc 200, when projected onto the first valve body 100, lies outside all inflow holes 111.

[0090] The aforementioned valve disc 200 is fixedly connected to the edge region of the first valve body 100 through its edge region. The connection methods include, but are not limited to, thermoforming, adhesive bonding, bonding, laser welding, or ultrasonic welding. To ensure connection strength while allowing free deformation of the central region of the valve disc 200, the connection is not a continuous circle, but is achieved by setting multiple independent connection points or connection areas. For example, at least one or N connection points can be evenly arranged on the circumference of the edge regions on the valve disc 200 and the first valve body 100, where N is a natural number greater than 0. The orthographic projection position of the connection point or connection area on the first valve body 100 must not overlap or intersect with the orthographic projection areas of all inflow holes 111 and subsequent guide holes 21. Furthermore, the number and spacing of connection points or connection areas are parameters that adjust the overall average stiffness of the valve disc 200, thereby affecting the valve's response frequency and shut-off performance. Generally speaking, the more connection points or connection areas there are, and the smaller the adjacent spacing, the stronger the edge constraint of the valve disc 200, the greater the average stiffness, and the faster the valve's response speed. Under reverse pressure, the valve disc 200 has better shut-off sealing performance. The connection point or connection area can also be unevenly distributed to achieve differentiated stiffness in different areas of the valve disc 200 to meet the needs of different frequency responses.

[0091] In the central region or near the center of the valve disc 200, one or more guide holes 21 penetrating its thickness are provided. The number and diameter of the guide holes 21 can be set according to actual needs, and may be equal to, less than, or slightly more than the number of inflow holes 111. The orthographic projection of the guide holes 21 on the first valve body 100 must be completely offset from the orthographic projection areas of all inflow holes 111, i.e., without any overlap. That is to say, from the top view, the guide holes 21 and the inflow holes 111 are offset.

[0092] The working principle of this miniature valve is based on the pressure difference on both sides of the valve disc 200, which drives its elastic deformation. Specifically, the pressure difference between the pressure P1 on the side of the fluid inlet 11 away from the valve disc 200 and the pressure P2 on the side of the guide hole 21 away from the first valve body 100 causes the valve disc 200 to undergo elastic deformation, thereby changing the relative position between the valve disc 200 and the first valve body 100. For example... Figure 2 As shown, when the valve is in static pressure balance or initial state or when the pressure difference is 0, the valve disc 200 relies on its own material elasticity to recover to slightly adhere to the surface of the first valve body 100, thereby preparing for the next pressure difference change.

[0093] like Figure 3 As shown, when fluid transport needs to be opened, i.e. when the fluid flows downstream, the pressure P1 (i.e., the pressure generated upstream) on the side of the fluid inlet 11 away from the valve disc 200 and the pressure P2 (i.e., the pressure generated downstream) on the side of the guide hole 21 away from the first valve body 100, the pressure difference between the two is P1>P2. The part of the valve disc 200 (i.e., the area covering the inlet hole 111) will bend and deform in the direction away from the first valve body 100, i.e., elastic bulging deformation. After the deformation occurs, the inlet hole 111, which was originally blocked by the surface of the valve disc 200, is immediately opened. The external fluid can enter the space between the first valve body 100 and the valve disc 200 through the inlet hole 111. Since the guide hole 21 and the inlet hole 111 are misaligned, the fluid needs to turn briefly in the space between the first valve body 100 and the valve disc 200, and then flow out smoothly with low resistance from the guide hole 21. The entire opening process is achieved by the overall bulging of the membrane. The flow channel is directly without an intermediate layer, the dead volume is about 0, and the response time is less than 1 millisecond.

[0094] Conversely, such as Figure 4 As shown, when the pressure condition reverses and the fluid flows backward, i.e., P1 < P2, a reverse pressure difference is formed from top to bottom. Under the action of this pressure difference, part of the valve disc 200 will also bend and deform in the direction closer to the first valve body 100, i.e., elastic rebound deformation, or concave deformation. The entire valve disc 200 quickly and tightly adheres to the surface of the first valve body 100. At this time, the surface of the valve disc 200 acts like a whole sealing gasket, tightly sealing all the inlet holes 111, blocking the path of fluid entering backward, and achieving reliable zero-leakage unidirectional shut-off.

[0095] In some embodiments, this miniature valve consists of only two components, resulting in a simple structure that eliminates the need for precise interlayer alignment and multiple sealing interfaces required by traditional multilayer valves. This significantly reduces assembly difficulty, improves production yield, and fundamentally reduces the risk of leakage. Furthermore, the opening and closing of the valve disc 200 is entirely driven autonomously by the fluid pressure difference, eliminating the need for external mechanisms such as springs or electromagnetic actuators. This achieves the functionality of a minimalist, low-resistance, and highly reliable valve.

[0096] This embodiment further optimizes the structure of the first valve body 100 to reduce flow resistance, suppress cavitation, improve sealing reliability, and extend the lifespan of the valve disc 200, such as... Figure 22-25 As shown, the first valve body 100 in this embodiment has one or more of the following features:

[0097] Specifically, such as Figure 25 As shown, at least one drag-reducing structure 12 is provided on the surface of the first valve body 100 facing the valve disc 200. That is, a number of grooves are etched or machined on the surface of the first valve body 100, which are drag-reducing grooves. These drag-reducing grooves are arranged alternately with the inflow holes 111. Crucially, the drag-reducing grooves are not directly connected to any of the inflow holes 111, that is, they are isolated from each other in three-dimensional space. The drag-reducing structure 12 can also be a series of parallel shallow grooves, dot matrix pits, or grid-like grooves. When the valve disc 200 abuts against the first valve body 100, the drag-reducing groove and the valve disc 200 immediately enclose to form a series of low-pressure buffer microcavities. Because the cavity of the low-pressure buffer microcavity is isolated from the main flow channel, the fluid within the cavity is instantly compressed / expanded, converting the pulsating kinetic energy into reversible elastic energy, which rapidly decays under viscous dissipation, significantly weakening the turbulence intensity of the fluid by 20%-30%, resulting in an overall flow resistance reduction of more than 10%. Simultaneously, the groove wall of the drag-reducing groove provides local support for the valve disc 200, preventing micro-fluttering of the valve disc 200 under high-speed fluid impact, thereby reducing cavitation noise and extending fatigue life. Since the drag-reducing groove is physically isolated from the inlet hole 111, it neither introduces additional leakage channels nor interferes with the main flow. In terms of manufacturing, it can be formed in the same photolithography and etching steps as the inlet hole 111, achieving low resistance, low noise, and long lifespan with zero additional cost and no additional processes. Furthermore, the drag-reducing groove continuously suppresses boundary layer separation, maintaining low noise at 40dB.

[0098] To improve the sealing effect between the valve disc 200 and the first valve body 100 when closed, a special sealing structure can be provided around each inlet hole 111 on the surface of the first valve body 100 facing the valve disc 200. This sealing structure can take various forms:

[0099] like Figure 22As shown, on the surface of the first valve body 100 facing the valve disc 200, an annular groove is formed around the outer periphery of each inflow hole 111, which is called an annular groove 13, and the annular groove 13 at least partially surrounds the inflow hole 111. Meanwhile, the orthographic projection of the annular groove 13 onto the valve disc 200, the orthographic projection of the inlet hole 111 onto the valve disc 200, and the guide hole 21 do not overlap simultaneously. That is, the flow channels of the annular groove 13 and the hole are spatially offset. The function of the annular groove 13 is to form an annular local expansion cavity when the valve disc 200 is closed. When the valve disc 200 is under countercurrent pressure and presses against the first valve body 100, the air or residual fluid in the annular groove 13 is compressed, i.e., the groove cavity is compressed, producing an effect similar to an elastic pad. This makes the contact stress distribution between the valve disc 200 and the edge of the inlet hole 111 more uniform, avoiding local stress peaks and even reducing local pressure peaks by about 30%, thereby significantly reducing the risk of microcrack initiation on the valve disc 200 and improving cycle life. Since the groove does not affect the cross-sectional area of ​​the main flow channel, it does not increase flow resistance or generate eddies. Meanwhile, the annular groove 13 is etched simultaneously with the inlet hole 111 during the photolithography stage, achieving vibration reduction, pressure equalization, and long lifespan with zero additional processes. This further improves the reliability and process consistency of the micro-valve under high-frequency and high-pressure differential conditions. Specifically, when the valve disc 200 is closed, its material is partially pressed into the annular groove 13 under pressure, increasing the contact area and forming a compression sealing effect similar to an O-ring. At the same time, the space inside the groove can absorb some of the impact energy.

[0100] like Figure 23 and 24 As shown, a raised annular structure, serving as a second support ring 14, is machined around each inlet hole 111 on the surface of the first valve body 100 facing the valve disc 200. The top of the second support ring 14 can form a precise line contact or a narrow surface contact with the valve disc 200. The line contact can generate high local pressure, achieving excellent sealing, while the narrow surface contact provides a certain support area while ensuring sealing.

[0101] Specifically, the outer diameter of the second support ring 14 is larger than the diameter of its corresponding inlet hole 111 to ensure that it can completely cover and surround the edge of the inlet hole 111, providing a rigid annular support surface for the valve disc 200. This prevents the flexible valve disc 200 diaphragm from being pressed into the inlet hole 111, causing excessive deformation, stress concentration, or sealing failure. Furthermore, it ensures sufficient effective flow area (over 90%) during downstream flow while also accommodating sensitive opening under low pressure and reliable shut-off under high pressure.

[0102] Furthermore, the inner region of the second support ring 14, i.e. the inner region of the ring, at least partially overlaps with the inflow hole 111, i.e., the inner diameter of the ring is less than or equal to the diameter of the inflow hole 111, thereby partially blocking the inflow hole 111. This restricts the main bending deformation area of ​​the valve disc 200 when closed to the vicinity of the top of the second support ring 14, thus preserving a sufficient flow cross section and transferring the maximum stress point of the membrane from the edge of the orifice to the more fatigue-resistant top region of the ring, reducing the probability of fatigue crack initiation and increasing the life of the valve disc 200 by more than double.

[0103] In addition, the orthographic projection of the inner region of the second support ring 14 onto the valve disc 200 does not overlap with all the guide holes 21. During the opening and closing of the valve disc 200, the diaphragm always avoids the valve hole region, avoiding local shearing and micro-tears, and maintaining flow linearity and long-term stability.

[0104] Furthermore, the second support ring 14 can also be processed or etched in the same step as the inflow hole 111 to form a single piece, without adding any process steps, thus achieving the characteristics of high rigidity support, low flow resistance, and long life.

[0105] Furthermore, the second support ring 14 can be configured as a single ring or a double ring. In this embodiment, a double ring is preferred, comprising an inner ring 142 and an outer ring 141 arranged concentrically. An annular groove 144 is formed between the inner ring 142 and the outer ring 141 (i.e., the top surface of the second support ring 14 in contact with the valve disc 200). This annular groove 144 is located inside the top surface of the second support ring 14 and does not intersect with the inner or outer circle of the second support ring 14, thereby forming a closed annular micro-elastic cavity. This micro-elastic cavity is compressed when the valve disc 200 is closed, generating additional elastic restoring force, making the contact stress distribution between the valve disc 200 and the second support ring 14 more uniform, avoiding fatigue cracks caused by local high pressure points. During the opening phase of the valve disc 200, the cavity quickly recovers its volume, reducing opening hysteresis and improving dynamic response. Since the annular groove 144 is completely located inside the second support ring 14 and does not penetrate the inner or outer circle, it neither weakens the overall rigidity of the second support ring 14 nor introduces new leakage paths. Meanwhile, it can be photolithographically formed with the second support ring 14 in one step, without any additional processes, and can achieve the characteristics of vibration reduction, pressure equalization and speed increase, further improving the reliability and consistency of the micro valve under high frequency and high pressure differential conditions.

[0106] To enable the annular groove 144 to have damping and pressure relief functions, one or more notches 143 communicating with the fluid can be made on the inner ring 142 or the outer ring 141. These notches 143 connect the annular groove 144 to the internal inflow hole 111, or connect the annular groove 144 to an external area. Thus, at the moment the valve disc 200 opens and closes, the fluid in the annular groove 144 can slowly flow in or out through the notches 143, forming controllable fluid damping. This effectively absorbs the impact energy of the valve disc 200's impact, reduces the amplitude of high-frequency flutter, and lowers the noise by approximately 20%. After backflow closure, the residual pressure in the groove can also be quickly released through the notches 143, preventing the valve disc 200 from being adsorbed onto the second support ring 14 and affecting the response speed of the next opening, thus improving response consistency. In addition, the notch 143 and the annular groove 144 are completed in the same photolithography step without adding a mask or process, so that the second support ring 14 has the triple functions of rigid fulcrum, adjustable damping and self-pressure relief, which significantly enhances the stability and life of the micro valve in high frequency and high pressure differential environment.

[0107] In some embodiments, such as Figure 16-20 As shown, the structure of the valve disc 200 has been optimized to further improve its deformation performance, reduce opening and closing pressure, and extend its service life.

[0108] Specifically, at least one corrugated region, a biomimetic corrugated structure 22, is formed on the valve disc 200 using photolithography, patterning, or molding processes. This corrugated structure 22 can guide and enhance the elastic deformation of the valve disc 200 under pressure. The corrugated structure 22 can be disposed on the surface of the valve disc 200 facing the first valve body 100, the surface facing away from the first valve body 100, or on both sides of the first valve body 100. Furthermore, the corrugated structure 22 is formed in the region corresponding to the inlet hole 111. The corrugated region is achieved by forming an undulating wave-shaped structure on the valve disc 200, with a wave-shaped cross-sectional profile including alternating upper convex regions 222 and lower convex regions 223 arranged from the center to the outer edge.

[0109] Specifically, such as Figure 19 and 20 As shown, the corrugated structure 22 resembles the bellows of an accordion. In downstream flow, P1 > P2, the upper convex region 222 arches outward (away from the first valve body 100), and the lower convex region 223 recedes inward, moving away from the first valve body 100. The entire corrugated structure 22 unfolds like an accordion, causing the valve disc 200 to present a pre-stressed arch shape. This allows the valve disc 200 to achieve greater deformation displacement with less force, thereby reducing the opening pressure threshold by approximately 25% and achieving a rapid and sensitive response. Figure 20As shown in b20. During reverse flow, P1 < P2, the corrugated structure 22 folds and rebounds, moving towards the direction closer to the first valve body 100. This helps the valve disc 200 to fit more quickly and smoothly against the first valve body 100, achieving instantaneous contact, enhancing the sealing effect, and ensuring zero-leakage shut-off. Figure 20 As shown in c20.

[0110] The outer contour boundary of the corrugated structure 22 does not completely cover the guide hole 21. Preferably, the guide hole 21 is located outside the umbrella surface of the corrugated structure 22. In this way, in the fully open state, the flow area of ​​the guide hole 21 will not be blocked by the corrugated structure 22, the utilization rate is maintained at 100%, and there is no additional dead volume.

[0111] On the corrugated structure 22, there is an upper convex region 222 closest to or adjacent to its center 224. The outer edge of the upper surface of the upper convex region 222 (i.e. the surface opposite to the first valve body 100) is projected onto the first valve body 100 outside the outline of its corresponding inlet hole 111. That is, when the valve is closed, the top of the upper convex region 222 will directly press against the surface of the first valve body 100 (or the second support ring 14), forming an annular external pressure contact band. This can prevent the edge of the valve disc 200 from warping and move the stress concentration area outward to the corrugated structure 22, rather than the flat part of the membrane, thereby improving fatigue life and ensuring the integrity of the seal. Furthermore, the inner edge of the upper surface of the convex region 222 is projected onto the first valve body 100 within the outline of its corresponding inlet hole 111. This allows the fluid ejected from the inlet hole 111 to directly impact the center of the corrugation (the area from the inner edge of the convex region 222 to its center), utilizing fluid force to more effectively drive the corrugation deformation and create a uniform pressure distribution. Specifically, the top surface of the convex region 222 closest to or adjacent to its center 224 on the corrugated structure 22 contacts the first valve body 100, reducing the contact area between the corrugated structure 22 and the first valve body 100, increasing pressure, and improving the sealing performance when the passage is closed.

[0112] The aforementioned corrugated structure 22 and valve flap 200 can be photolithographically formed simultaneously, with zero additional processes, taking into account low stress, large stroke, long life and wafer-level batch consistency.

[0113] like Figure 18 and 19 As shown, in order to further enhance the stiffness and stability of the central part 224 of the corrugated structure 22 and prevent it from undergoing plastic deformation or collapse during repeated deformation, a reinforcing structure can be provided in the central part 224 of the corrugated structure 22. This reinforcing structure can take the following two forms:

[0114] like Figure 18As shown, one approach involves fabricating at least one raised rib, or at least one support rib 221, on the upper or lower surface, or both surfaces, of the central portion 224 of the corrugated structure 22. The support ribs 221 can be arranged radially from the center, where all ribs converge at the center point to enhance the strength of the central support, resulting in a faster and more symmetrical opening action of the valve disc 200. Alternatively, they can be arranged off-center, with the convergence point of the support ribs deviating from the center, shifting the area of ​​maximum stress concentration outwards and delaying fatigue crack initiation. Finally, they can be arranged obliquely, breaking the axial symmetry of the structure, suppressing resonance and flutter at specific frequencies, and reducing noise. All of these arrangements of the support ribs 221 can be etched and formed simultaneously with the corrugated structure 22, achieving adjustable stiffness, vibration reduction, noise reduction, and long service life with zero additional steps.

[0115] like Figure 19 As shown, another form involves filling the grooves on the upper or lower surface, or both surfaces, of the center portion 224 of the corrugated structure 22 with lightweight filler blocks, such as... Figure 19 As shown in b19, the lightweight filler block is made of a lightweight and non-deformable material, such as porous silica (SiO2), hollow glass microspheres, PDMS composite, or ultralight aluminosilicate foam. In other words, the lightweight filler block acts as a lightweight core, increasing the bending stiffness of the central portion 224 of the corrugated structure 22 by 20%-40% without significantly increasing the mass of the valve disc 200. This makes the deformation of the valve disc 200 more controllable and reduces opening and closing hysteresis. In some embodiments, a lightweight filler block is provided on the upper or lower surface of the central portion 224 of the corrugated structure 22, and a support rib 221 is provided on the opposite surface, or both the support rib 221 and the lightweight filler block are provided on the same surface. This arrangement allows the lightweight filler block and the support rib 221 to jointly transfer bending stress from the film itself to the lightweight filler block, further optimizing stress distribution and significantly extending fatigue life. Furthermore, the porous material of the lightweight filler block can absorb the energy of local fluid microjets, reducing cavitation collapse impact and lowering noise and cavitation erosion. The aforementioned filling material can be formed at the wafer level in one step through processes such as spin coating, spraying, or sol-gel method, and can be seamlessly integrated with existing MEMS production lines to achieve the characteristics of lightweight, high strength, and long life.

[0116] In some embodiments, such as Figure 5-15 As shown, the valve also includes a second valve body 300 and a corresponding constraint structure to optimize the movement stroke of the valve disc 200 and improve sealing reliability and a more stable flow path.

[0117] The second valve body 300 is also a thin sheet or plate structure, arranged parallel to the first valve body 100, and sandwiching the valve disc 200 in between. Furthermore, the connection methods of the second valve body 300 include, but are not limited to, the following: synchronous hot pressing or adhesive bonding with the first valve body 100 via the valve disc 200 as an intermediate layer; forming an annular sealing band with the opposing surfaces of the second valve body 100 through laser welding, ultrasonic welding, or anodic bonding; a snap-fit ​​or pin structure on the outer edge of the second valve body 300, forming a mechanical fit with the corresponding groove on the edge of the first valve body 100, and then reinforced by adhesive sealing or welding; three layers (i.e., as shown in the image)... Figure 5 As shown, the first valve body 100, valve disc 200, and second valve body 300 are bonded to form a single sealing interface, which can effectively reduce the leakage rate. The material of the second valve body 300 is typically similar to that of the first valve body 100. A fluid outlet 33 is provided on the second valve body 300 to guide the fluid flowing out through the guide hole 21 to a downstream channel. The second valve body 300 can be connected to the first valve body 100 via the valve disc 200, or the second valve body 300 can be directly connected to the first valve body 100.

[0118] The constraint structure is disposed on the surface of the second valve body 300 relative to the first valve body 100 and / or between the first valve body 100 and the valve disc 200, for abutting against the deformed portion of the valve disc 200, thereby providing physical support.

[0119] Specifically, such as Figure 13 As shown, the second valve body 300 includes a valve plate 31 or valve disc. At least one protrusion 32 is machined onto the surface of the valve plate 31 facing the valve disc 200. The protrusion 32 can be a continuous annular boss or an array of discrete protrusions. The protrusion 32 is positioned corresponding to the projection area of ​​the connection point or connection area between the valve disc 200 and the first valve body 100 onto the second valve body 300. The top of the protrusion 32 contacts the valve disc 200 when it bulges excessively, limiting its maximum upward displacement and preventing material fatigue or damage due to excessive deformation. Furthermore, the protrusion 32 and the first valve body 100 together clamp the valve disc 200, providing additional annular preload and further enhancing the reverse sealing capability.

[0120] Around the protrusion 32 (i.e., the area inside the annular boss or between discrete protrusions), at least one outlet hole 331 serving as a fluid outlet 33 is machined. The orthogonal projection of the outlet hole 331 onto the valve disc 200 should at least partially overlap with the guide hole 21 to ensure that the fluid can smoothly enter the outlet hole 331 after flowing out of the guide hole 21, greatly reducing flow resistance and response time. In addition, at least one spacer hole 332 serving as a fluid outlet 33 is also provided on the valve plate 31. The function of the spacer hole 332 is to provide additional flow space for the fluid or to balance the pressure. Its position can be coaxial and collinear with the inlet hole 111, or it can be staggered.

[0121] like Figure 8 As shown, the outlet orifice 331 and the spacer orifice 332 can operate independently without intersecting. In this case, the outlet orifice 331 works independently, which is suitable for low flow rate and low back pressure scenarios. Figure 9 As shown, they can also be designed to be interconnected, intersecting, crossing, or enveloped to form outflow regions, thus creating larger and more complex outflow areas to adapt to different flow rate and back pressure requirements. For example, Figure 12 As shown, when the outlet hole 331 intersects with the spacer hole 332 to form an outlet hole 34, the shape of the hole can be... Figure 12 The wire mesh structure shown in a12, the linear type shown in b12, or the large-diameter circular type shown in c12 are all examples of the wire mesh structure. Of course, the shape of the hole can also be elliptical, rectangular, square, waist-shaped, or irregular.

[0122] Therefore, by simply replacing the second valve body 300 with a different array of outlet holes 331, the flow rate or pressure rating can be quickly switched, thus shortening the serialization development cycle.

[0123] Furthermore, the constraint structure includes a separate limiting ring 400, which can be a ring-shaped component with a central through hole, and can be integrally formed (e.g., Figure 13 (a13 in the figure is directly etched on the valve plate 31) or a separate connection (such as...) Figure 13 (b13 is manufactured separately and then bonded) and fixed to the surface of the valve plate 31. The through portion 41 enclosed by the limiting ring 400 constitutes a receiving space, such as... Figure 11 As shown, when valve disc 200 bulges under a positive pressure differential (i.e., in the direction of flow), its bulging portion can extend into this through-hole 41, as... Figure 13As shown in a13 and c13, the depth (height) of the through portion 41 is greater than, equal to, or less than the height of the protrusion 32. Thus, the bottom surface (i.e., the surface of the valve plate 31) and the sidewalls of the through portion 41 work together to restrict the upward displacement of the valve disc 200 and provide guidance and space for its bulging deformation, making the deformation more regular and stable. Furthermore, when the depth of the through portion 41 is equal to the height of the protrusion 32, the valve disc 200 and the second valve body 300 can be coplanarly bonded through the protrusion 32, achieving wafer-level one-time alignment and batch bonding, significantly reducing the risk of multilayer misalignment, and minimizing the overall thickness. If the height of the protrusion 32 is greater than the depth of the through portion 41, the connection point or connection area between the first valve body 100 and the valve disc 200 is subjected to a controllable clamping force provided by the protrusion 32, achieving an elastic pre-pressure seal. This allows for a double-layer redundant seal without the need for additional adhesive or solder, improving pressure resistance and simplifying the process steps. In this configuration, the projection of the through portion 41 onto the first valve body 100 covers all inlet holes 111, forming an integrated flow channel chamber, reducing fluid diversion abruptly by 90% and lowering the flow resistance coefficient. In some embodiments, the protrusion 32 is in the form of one or more support beams and is connected to the outer wall of the through portion 41.

[0124] Furthermore, such as Figure 13 As shown in a13-c13, the top surface of the protrusion 32 can be flat, forming a large-area uniform contact surface with the valve disc 200 or the first valve body 100, increasing the effective bonding area, reducing local stress concentration, and improving bonding strength and long-term sealing reliability. Figure 13 d13 and Figure 14 The surface shown can also be designed as an outwardly convex arc (such as a sphere or cylinder). Under pressure, the arc surface undergoes progressive elastic deformation, forming an adaptive sealing ring. This allows for adhesive-free adaptive bonding between wafers with different thickness tolerances, significantly widening process tolerances and reducing assembly stress. Simultaneously, the curvature of the arc surface directs fluid dynamic pressure towards the outlet 73 sink, further suppressing cavitation and reducing flow resistance. Figure 14 The protrusion 32 in the middle can form an arched surface together with the outlet hole 331 and the spacer hole 332.

[0125] Furthermore, such as Figure 15As shown, the diameter of the valve disc 200 is slightly smaller than the diameter of the through portion 41. This means that the projection of the valve disc 200 onto the second valve body 300 is completely covered by the through portion 41 on the second valve body 300. This creates an annular buffer zone around the valve disc 200, between the inner wall of the limiting ring 400 and the edge of the valve disc 200. This buffer zone helps to balance the surrounding pressure during the opening and closing of the valve disc 200, improving the response speed. This buffer zone can also act as a secondary pressure relief chamber, rapidly absorbing the micro-jet kinetic energy generated by cavitation collapse, suppressing cavitation noise and diaphragm erosion, while preventing frictional jamming between the edge of the valve disc 200 and the inner wall of the limiting ring 400, ensuring that the valve disc 200 always maintains axially symmetrical expansion.

[0126] like Figure 6-10 As shown, the constraint structure also includes a first support layer 500, which is a single, thin sheet with a hollow structure, typically made of a rigid material such as silicon, stainless steel, or hard polymer, and is also formed through precision machining, such as photolithography / etching. The first support layer 500 is disposed between the first valve body 100 and the valve disc 200, either in close contact with both or with a small gap. The first support layer 500 is provided with a support portion 51 corresponding to the inlet hole 111. The support portion 51 specifically includes at least one first support ring 511, and a connecting beam 512 connecting each of the first support rings 511 or connecting the first support rings 511 to the outer frame of the first support layer 500. The support portion 51 is used to allow fluid to pass through the fluid inlet 11 and to provide support and limit the deformation of the valve disc 200.

[0127] like Figure 10 As shown, the outer diameter of the first support ring 511 is larger than the orifice diameter of its corresponding fluid inlet 11, ensuring that the first support ring 511 can completely cover the edge area of ​​the fluid inlet 11. When the valve disc 200 is subjected to reverse high pressure, the first support ring 511 provides a rigid support surface to prevent the diaphragm from collapsing into the orifice, thus avoiding the sudden reduction of the flow channel cross-sectional area and sealing failure caused by the collapse of the traditional thin valve disc 200.

[0128] However, the inner diameter of the first support ring 511 can be selected in several ways: such as Figure 10 As shown in b10, the inner diameter of the first support ring 511 is equal to the orifice diameter of the fluid inlet 11. At this time, the inner wall of the first support ring 511 is aligned with the inlet edge, providing precise edge support.

[0129] like Figure 10 As shown in a10, the inner diameter of the first support ring 511 is smaller than the orifice diameter of the fluid inlet 11. In this case, the first support ring 511 will partially block the inlet, but provides a larger support area, which is suitable for occasions that require higher pressure resistance.

[0130] like Figure 10As shown in c10, the inner diameter of the first support ring 511 is larger than the orifice diameter of the fluid inlet 11. At this time, the first support ring 511 mainly provides annular peripheral support, and the central flow area is completely open.

[0131] Therefore, regardless of the inner diameter setting, when the valve disc 200 is pressed against the first valve body 100 under reverse pressure differential, the surface of the first support ring 511 will provide a rigid support surface for the valve disc 200, preventing the valve disc 200 diaphragm from sinking into the orifice of the fluid inlet 11, thereby ensuring an effective sealing surface and preventing stress concentration and fatigue damage caused by excessive diaphragm indentation. The projection of the area inside the orifice of the first support ring 511 onto the valve disc 200 does not overlap with the guide hole 21. Simultaneously, the partial shielding arrangement retains sufficient flow area while limiting the bending area of ​​the diaphragm within the edge of the annular orifice. Without the first support layer 500, the valve disc 200 would only have the plane of the first valve body 100 (or a sealing structure or drag-reducing structure 12) on one side. In this case, the valve disc 200 would have less deformation resistance under positive pressure differential, allowing it to open rapidly at lower pressure differentials, such as <5 kPa, with an extremely sensitive response time reduced to the millisecond level. Furthermore, in some embodiments, the first support layer 500 can serve as an insert, enabling micro-valve chips based on the same core (first valve body 100 and valve disc 200) to quickly switch between operating modes suitable for different pressure scenarios through simple addition or removal operations, greatly improving the efficiency of product series development. The connecting beam 512 ensures the structural stability and positional accuracy of the first support ring 511.

[0132] In some embodiments, such as Figure 21 As shown, a second support layer 600 is added between the valve disc 200 and the second valve body 300. The main function of the second support layer 600 is to provide a flexible and breathable auxiliary support for the valve disc 200 under static pressure or low differential pressure conditions, allowing it to better fit any microscopic unevenness on the surface of the first valve body 100, thereby enhancing the sealing performance in the closed state. The orthogonal projection of the second support layer 600 onto the valve disc 200 should completely cover the area where all the guide holes 21 are located to ensure that they do not block the main flow channel.

[0133] Among them, such as Figure 21 As shown in b21, the second support layer 600 can be a ring structure, the shape of which matches the through portion 41 of the limiting ring 400, and is filled in the through portion 41, located between the valve disc 200 and the bottom surface of the valve plate 31.

[0134] like Figure 21 As shown in a21, the second support layer 600 can also be a sheet structure, a thin layer with a larger coverage area, which can cover the entire surface or main part of the valve disc 200 facing away from the first valve body 100.

[0135] The material of the second support layer 600 needs to be soft, have a certain degree of compression resilience, and be breathable or water-permeable. A preferred embodiment is made of a porous sponge material, such as a polymer open-cell foam (e.g., polyurethane PU foam). Other optional materials include gel materials with a certain degree of support, or 3D mesh fiber structure materials. These materials can undergo elastic deformation under pressure, filling microscopic gaps, while allowing trace amounts of air or fluid to pass through, preventing vacuum adsorption between the valve disc 200 and the second support layer 600, which would affect the opening response.

[0136] In addition, the second support layer 600 acts like a soft mattress, supporting the valve disc 200 so that it can achieve more uniform and tighter surface or line contact with the sealing structure of the first valve body 100 when closed. This is particularly beneficial for dealing with minor leakage problems under low pressure differentials and improves the overall sealing performance of the valve.

[0137] The miniature valve of any of the above embodiments is applied in a piezoelectric pump 700, such as Figure 26 As shown, the piezoelectric pump 700 includes at least one housing, each housing having a pump chamber 71 formed therein (i.e., the pump chamber 71 is formed by the relative arrangement of the piezoelectric element 7 described below with the housing), and the housing having at least one inlet 72 and / or at least one outlet 73. In this embodiment, at least one micro-valve is installed at the inlet 72 of at least one pump chamber 71 as an inlet valve 721; and / or at least one micro-valve is installed at the outlet 73 of at least one pump chamber 71 as an outlet valve 731.

[0138] At least one piezoelectric element 7 is disposed within the pump chamber 71. The piezoelectric element 7 typically consists of a piezoelectric wafer 75, a drive circuit 76 (such as a flexible circuit board), and a substrate 74. When an alternating voltage is applied to the piezoelectric wafer 75, it undergoes periodic bending vibration, thereby driving the diaphragm or pump chamber wall connected to it to move, causing the volume of the pump chamber 71 to alternately increase and decrease. When the volume of the pump chamber 71 increases, the internal pressure decreases, the inlet valve 721 opens, and the outlet valve 731 closes, allowing fluid to be drawn into the pump chamber 71. When the volume of the pump chamber 71 decreases, the internal pressure increases, the inlet valve 721 closes, and the outlet valve 731 opens, allowing fluid to be discharged from the pump chamber 71. This cycle repeats, achieving unidirectional continuous fluid delivery. A through-hole 77, which may or may not be connected to the pump chamber 71, may be provided on the piezoelectric element 7. A micro-valve may also be selectively disposed within the through-hole 77 as a connecting valve to further regulate the flow path.

[0139] Specifically, the pump body structure has several optional implementations, including but not limited to the following configurations:

[0140] Single-shell structure (e.g.) Figure 27(a27): An outlet valve 731 (or inlet valve 721) can be provided at the center of the housing. The piezoelectric element 7 is provided with a through hole 77 that is not connected to the pump chamber 71. There is only one housing. Several holes can be opened on the side of the housing. The inlet valve 721 (or outlet valve 731) is provided in the hole. Alternatively, no additional holes can be provided on the housing, or the housing can work by relying solely on the cooperation between the center valve and the through hole valve on the piezoelectric element 7.

[0141] Double-shell structure (e.g.) Figure 26 (a26, b26, c26): There are two housings, which can be arranged symmetrically. Each housing can have an inlet valve 721 or an outlet valve 731 at its center. The piezoelectric element 7 can have two through holes 77, which can be connected to or not connected to the pump chamber 71. A connecting valve can be optionally installed in the through hole 77. One or more additional holes can be opened on the bottom and / or side of the housing, and miniature valves can be installed in the holes or no valves can be installed. The types of the central valve and the peripheral valve can be interchanged (i.e., the central valve is the inlet valve 721 and the peripheral valve is the outlet valve 731, or vice versa), so as to achieve different flow path combinations.

[0142] Multi-shell stacked structure (e.g.) Figure 27 (b27): There are multiple housings, for example, four housings stacked in layers. Each housing can be equipped with an inlet valve 721 or an outlet valve 731 at its center. Multiple piezoelectric elements 7 can be configured. Each piezoelectric element 7 can be provided with a through hole 77 communicating with the pump chamber 71. A connecting valve can be optionally installed in the through hole 77. One or more holes can also be opened on the bottom and / or side of the housing. A micro valve can be installed in the hole or no valve can be installed. Holes can also be opened on the housing and configured with corresponding micro valves.

[0143] In addition, the aforementioned inlet 72 or outlet 73 is positioned relative to the position of the largest relative support point of the piezoelectric element 7. That is, it is arranged relative to the position of the piezoelectric element 7 with the largest amplitude relative to its support point. This arrangement can effectively drive the fluid through the valve body, significantly improving the pump's flow rate and control effect.

[0144] In all the above layouts, the type of valve at the center of the housing, the position and number of auxiliary holes on the housing and whether or not they are equipped with valves, and the number of through holes 77 on the piezoelectric element 7 and whether or not they are equipped with valves and their types can all be combined and adjusted in a variety of ways according to the actual pumping requirements.

[0145] These different structural configurations can optimize the flow field distribution inside the pump, enabling more complex multi-stage or coordinated pumping actions. This helps to improve the stability of the output flow rate and increase the output pressure. Furthermore, without significantly increasing the overall volume, the pump's overall performance can be enhanced through superposition or complementary effects.

[0146] The miniature valve of this invention is particularly suitable for applications with stringent requirements for size, power consumption and reliability, such as implantable drug infusion systems, microfluidic chips, MEMS sensor cooling devices, portable analytical instruments and other precision flow control fields, due to its simple structure, rapid response, reliable sealing, long life and easy miniaturization and integration.

[0147] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the invention without departing from the principles and spirit of the invention, and all such changes should fall within the protection scope of the claims of the present invention.

Claims

1. A miniature valve, characterized in that, include: The first valve body is equipped with a fluid inlet; A valve disc is connected to the first valve body, and a flow guide hole is provided on the valve disc; The valve disc can elastically deform in response to the pressure difference between the pressure on the side of the fluid inlet away from the valve disc and the pressure on the side of the guide hole away from the first valve body, thereby changing the relative position between the valve disc and the first valve body, so that the fluid passage flowing through the guide hole is opened or closed.

2. The miniature valve according to claim 1, characterized in that, The elastic deformation of the valve disc includes: When the pressure on the side of the fluid inlet away from the valve disc is greater than the pressure on the side of the guide hole away from the first valve body, the valve disc bends and deforms in the direction away from the first valve body, so that the fluid can flow out through the guide hole. When the pressure on the side of the fluid inlet away from the valve disc is less than the pressure on the side of the guide hole away from the first valve body, the valve disc bends and deforms toward the direction closer to the first valve body to seal the area where the fluid inlet is located.

3. The miniature valve according to claim 1, characterized in that, Also includes: The second valve body is located on one side of the valve disc and is disposed opposite to the first valve body, and is provided with a fluid outlet; A constraint structure is disposed on the surface of the second valve body relative to the first valve body and / or between the first valve body and the valve disc, the constraint structure being used to abut against the deformed portion of the valve disc for support.

4. The miniature valve according to claim 3, characterized in that, The second valve body includes a valve plate, the valve plate being provided with a protrusion, and at least one outlet hole and at least one spacer hole being formed around the protrusion as the fluid outlet; The outlet hole may or may not intersect with the spacer hole.

5. The miniature valve according to claim 4, characterized in that, The constraint structure includes a limiting ring, which is integrally formed with or separately connected to the surface of the valve plate; The limiting ring has a through portion for accommodating the portion of the valve disc that bulges toward the direction of the second valve body.

6. The miniature valve according to claim 5, characterized in that, The height of the through portion is greater than or equal to the height of the protrusion, which is used to limit the maximum displacement of the valve disc when it deforms toward the second valve body.

7. The miniature valve according to claim 4, characterized in that, The top of the protrusion is either a flat surface or an outwardly convex arc surface.

8. The miniature valve according to claim 4, characterized in that, The projection of the outlet hole onto the valve disc at least partially overlaps with the guide hole to form a fluid passage, and the spacer hole is coaxial and collinear with the fluid inlet.

9. The miniature valve according to claim 5, characterized in that, The diameter of the valve disc is smaller than the diameter of the through portion, and the through portion around the valve disc forms an annular buffer zone.

10. The miniature valve according to claim 3, characterized in that, The constraint structure further includes a first support layer, which is disposed between the first valve body and the valve disc. The first support layer is provided with a support portion corresponding to the fluid inlet. The support portion is used to allow fluid to pass through the fluid inlet and to provide support and limit the portion of the valve disc that is deformed.

11. The miniature valve according to claim 10, characterized in that, The support includes at least one first support ring and a connecting beam for interconnection with the first support ring, wherein the outer diameter of the first support ring is larger than the orifice diameter of the fluid inlet.

12. The miniature valve according to claim 1, characterized in that, The valve disc surface is provided with at least one corrugated structure to guide and enhance the elastic deformation of the valve disc under pressure.

13. The miniature valve according to claim 12, characterized in that, The cross-sectional profile of the corrugated structure is wavy, including alternating upper and lower convex regions; When the pressure on the side of the fluid inlet away from the valve disc is greater than the pressure on the side of the guide hole away from the first valve body, the upper convex area arches outward and the lower convex area is concave, moving in a direction away from the first valve body; When the pressure on the side of the fluid inlet away from the valve disc is less than the pressure on the side of the guide hole away from the first valve body, the upper and lower convex areas fold back and move toward the direction closer to the first valve body.

14. The miniature valve according to claim 13, characterized in that, The projection of the inner edge of the upper convex area of ​​the adjacent corrugated structure onto the first valve body falls within the outline of the fluid inlet; The projection of the outer edge of the upper convex region of the adjacent corrugated structure onto the first valve body falls outside the outline of the fluid inlet.

15. The miniature valve according to claim 14, characterized in that, The corrugated structure is provided with a reinforcing structure at its center, which is at least one support rib provided on the upper and / or lower surfaces of the center. Alternatively, the reinforcing structure may be a lightweight filler block that fills the upper and / or lower surfaces of the central portion.

16. The miniature valve according to claim 15, characterized in that, The support ribs are arranged in a central radial, non-central offset, or non-radial oblique pattern.

17. The miniature valve according to claim 15, characterized in that, The lightweight filler block is made of porous SiO2, hollow glass microspheres, PDMS composite or aluminosilicate foam.

18. The miniature valve according to claim 3, characterized in that, A second support layer is provided between the valve disc and the second valve body, and the projection of the second support layer on the valve disc completely covers the flow guide hole.

19. The miniature valve according to claim 18, characterized in that, The second support layer is a ring-shaped structure or a sheet-like structure; The second support layer is made of porous sponge, aerogel or 3D mesh fiber.

20. The miniature valve according to claim 1, characterized in that, The surface of the first valve body facing the valve disc is provided with a sealing structure surrounding the fluid inlet, which is used to contact the valve disc to achieve a seal when the valve disc deforms towards the first valve body.

21. The miniature valve according to claim 20, characterized in that, The sealing structure is an annular groove that surrounds the fluid inlet and is recessed into the first valve body.

22. The miniature valve according to claim 20, characterized in that, The sealing structure includes a second support ring protruding from the surface of the first valve body, and the second support ring forms line contact or surface contact with the valve disc.

23. The miniature valve according to claim 22, characterized in that, The second support ring includes an inner ring body and an outer ring body arranged concentrically, an annular groove is formed between the inner ring body and the outer ring body, and at least one notch for fluid flow is provided on the inner ring body or the outer ring body.

24. The miniature valve according to claim 1, characterized in that, The surface of the first valve body facing the valve disc is also provided with at least one drag-reducing structure, which is isolated from the fluid inlet and is used to support the first valve body.

25. A piezoelectric pump, characterized in that, include: At least one housing, the housing having at least one inlet and / or at least one outlet, the at least one inlet being provided with at least one inlet valve, and / or the at least one outlet being provided with at least one outlet valve; At least one piezoelectric element is arranged opposite to the housing to form a pump chamber; The inlet valve and outlet valve are miniature valves as described in any one of claims 1 to 24.

26. The piezoelectric pump according to claim 25, characterized in that, The housing is a single unit; Alternatively, there are two housings, which are stacked opposite each other, with the piezoelectric element located between the two housings; Alternatively, there may be multiple housings, which are stacked sequentially; there may also be multiple piezoelectric elements, which are arranged alternately with the housings.

27. The piezoelectric pump according to claim 26, characterized in that, The piezoelectric element is provided with at least one through hole communicating with the pump chamber, and at least one of the micro valves is provided in the at least one through hole; Alternatively, the pump chamber is not connected to the through hole.

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