A pump-valve integrated gas pressure control assembly based on shape memory alloy valve

Abstract

The application relates to a pump-valve integrated air pressure control assembly based on a shape memory alloy valve, which comprises an air pump and a shape memory alloy valve in air-tight connection, the shape memory alloy valve comprising a valve base and a valve cover; the valve base is provided with a valve air outlet and a valve air inlet, and the air outlet pipe of the air pump is located in the valve cavity through the valve air inlet; a plunger is slidably connected in the valve base, the plunger is connected with an SMA wire, the SMA wire is pressure-connected with a terminal, a pin is inserted in the terminal, and the pin is fixed on a fixed base; the plunger is provided with a plug, and the plug is provided with a spring; the top of the valve cover is provided with a valve air outlet, and the valve air outlet is air-tightly connected with a valve air outlet pipe. The pump-valve integrated air pressure control assembly based on the shape memory alloy valve can solve the problems of large debugging workload, insufficient control parameter multiplicity, insufficient pressure control consistency and limited small-size arrangement in the product development, prototype verification and batch manufacturing processes.

Description

Technical Field

[0001] This invention relates to the field of pneumatic control technology for electronic blood pressure measuring devices, and specifically to an integrated pump-valve pneumatic control component based on a shape memory alloy valve. Background Technology

[0002] Electronic blood pressure measuring devices typically require a gas source to inflate the cuff or bladder, and to maintain, regulate, and release the pressure within the cuff or bladder during measurement. To accomplish this, existing products usually include a gas source, valve body, connecting tubing, connectors, pressure sensing elements, and control circuitry. They control the inflow and outflow of gas to achieve pressurization, depressurization, and post-measurement venting. For oscillometric blood pressure measuring devices, the stability of the gas path structure, the controllability of the venting process, and the pneumatic consistency between different products directly affect the repeatability of pressure changes and the engineering stability of the measurement process.

[0003] Existing pneumatic control structures typically employ a split layout, requiring separate installation of the air source, valve body, and connecting air circuits, which are then connected via external pipelines or connectors. This results in numerous connection points and sealing interfaces. Changes in pipeline length, diameter, bends, connector assembly status, and the relative positions of different components can all alter pneumatic impedance, pressure transmission paths, and dynamic response characteristics, making the overall system's functionality highly sensitive to structural layout and assembly consistency. Consequently, during product development, prototype verification, and mass production, issues such as substantial debugging workload, insufficient reusability of control parameters, inadequate pressure control consistency, and limitations on miniaturized layout are likely to arise.

[0004] Therefore, existing technologies have shortcomings and need to be improved and developed. Summary of the Invention

[0005] The present invention provides an integrated pump and valve pneumatic control component based on a shape memory alloy valve, which is used to solve the problems that are easy to encounter in product development, prototype verification and mass production, such as large debugging workload, insufficient reusability of control parameters, insufficient consistency of pressure control and limited miniaturization layout.

[0006] This invention provides an integrated pneumatic control component for a pump and valve based on a shape memory alloy valve, comprising an airtightly connected air pump and a shape memory alloy valve. The shape memory alloy valve includes a valve base and a valve cover that fits onto and is airtightly connected to the valve base. The valve base and the valve cover together form a valve cavity.

[0007] The valve base has a valve vent on its side that connects the inside and outside of the valve cavity; the bottom of the valve base has a valve inlet that connects the inside and outside of the valve cavity. A boss is fixed on one side of the valve inlet, and two second ribs protrude from the boss. An opening is formed between the two second ribs. When the air pump is airtightly connected to the shape memory alloy valve, the air outlet pipe of the air pump passes through the valve inlet and the opening and is located inside the valve cavity.

[0008] An insulated plunger is slidably connected between the two second ribs. The upper and lower surfaces of the plunger have through-hole air intake channels to accommodate the air outlet pipe of the air pump passing through the opening. A limiting groove is formed on one end of the plunger to accommodate an SMA wire. When the SMA wire is energized and contracts, it pulls the plunger towards the valve vent. Terminals are crimped to both ends of the SMA wire, and a pin is inserted into each terminal. Each pin is individually fixed to an insulated fixing base protruding from the inner bottom surface of the valve base. One end of the pin is fixed inside the fixing base, and the other end passes through the valve cover. A plug protrudes from the other end of the plunger towards the valve vent. A spring is fitted onto the plug, with one end fixed to the plunger and the other end fixed to the inner sidewall of the valve base, to provide a restoring force to the plunger away from the valve vent.

[0009] The top of the valve cover has a valve outlet that connects the inside and outside of the valve cavity, and the valve outlet is airtightly connected to a valve outlet pipe on the side facing away from the valve cavity; the top of the valve cover also has two through holes that connect the inside and outside of the valve cavity and are adapted to the protrusion positions of the two pins; the bottom of the valve cover, in a position that avoids the valve outlet, has a first rib protruding to abut against the plunger.

[0010] Furthermore, the valve cover protrudes towards the valve cavity to form a sealing protrusion, which is inserted into the cavity formed by the inner wall of the valve base, and the outer contour of the sealing protrusion is adapted to the inner wall contour of the valve base.

[0011] Furthermore, a rubber ring is fitted around the outer contour of the sealing protrusion to seal the assembly gap between the outer peripheral surface of the sealing protrusion and the inner sidewall of the valve base.

[0012] Furthermore, the valve base and the valve cover are connected by ultrasonic welding or adhesive bonding to form an airtight connection between the valve base and the valve cover.

[0013] Furthermore, the valve base is airtightly connected to the air pump in the connection area surrounding the valve inlet by ultrasonic welding or adhesive bonding.

[0014] Furthermore, each of the pins is inserted into the corresponding through hole, and the gap between the pin and the hole wall of the corresponding through hole is sealed with insulating sealant.

[0015] Furthermore, the plug is a rubber plug or an insulating elastic plug that elastically abuts against the inner edge of the valve vent.

[0016] Furthermore, a flexible spring sheet is fixed to the side of the plug facing the valve vent. The flexible spring sheet protrudes towards the valve vent and elastically fits against the inner edge of the valve vent when the plug seals the valve vent.

[0017] Furthermore, the spring is a bias spring, used to apply a reset bias force to the plunger in a direction away from the valve vent.

[0018] Furthermore, when viewed from above, the air intake channel is racetrack-shaped. When the SMA wire is not energized, the air pump's outlet pipe is located at the end of the air intake channel near the plug, and the outer contour of the air pump's outlet pipe is adapted to the semi-circular end of the racetrack shape. Define the maximum displacement of the plunger along the direction defined by the second rib as d, and the length of the air intake channel along the sliding direction of the plunger as D, then D > d.

[0019] Beneficial effects:

[0020] As can be seen from the above technical solutions, the present invention provides an integrated pneumatic pressure control component for pumps and valves based on shape memory alloy valves, which has the following beneficial effects:

[0021] 1. Reduce the degree to which gas path parameters are affected by external structures.

[0022] This application integrates an air pump and a shape memory alloy valve into a gas-tight, unified assembly. The air pump's outlet pipe extends into the valve chamber via the valve inlet, opening, and plunger's inlet channel. The path of gas entering the valve chamber from the air pump's output is primarily defined by the valve base, boss, opening, plunger inlet channel, and the valve chamber formed by the valve cover and valve base. Since the critical air path no longer relies heavily on external hoses, connectors, and their relative positions after assembly, the impact of pipe length, bends, and connector assembly differences on aerodynamic impedance and pressure transmission is reduced. This structure allows core air path parameters to be largely determined by the prefabricated structure, improving the consistency of pressure response between different machines and reducing the impact of subsequent overall structural adjustments on the core air pressure control function.

[0023] 2. The same valve body structure can accommodate pressurization, linear venting, and rapid exhaust.

[0024] In this application, the SMA wire, plunger, plug, and spring constitute a mutually opposing drive-reset structure. When the SMA wire is energized and contracts, it pulls the plunger towards the valve vent, causing the plug to gradually approach or block the valve vent. When the SMA wire is de-energized or its electrical parameters decrease, the spring applies a reset force to the plunger, causing the plug to move away from the valve vent, thereby opening the vent passage. By adjusting the drive electrical parameters of the SMA wire, the plunger can be in different positions, such as fully closed, partially open, or fully open, allowing the air pump to supply air to the airbag, the airbag to deflate in a controlled manner, and the airbag to de-exhaust rapidly within the same structure. This solution avoids the structural space and control complexity caused by setting up multiple independent valves, and is beneficial for improving the miniaturization and modularity of the pneumatic control components.

[0025] 3. Improve the stability of plunger movement and the repeatability of vent opening control.

[0026] This application employs two second ribs on the valve base boss to guide the plunger laterally, and a first rib at the bottom of the valve cover abuts against the plunger to restrict its vertical position. The first and second ribs together limit the plunger's freedom of movement within the valve cavity, allowing the plunger to move closer to or further away from the valve vent in a predetermined direction. This structure helps reduce the risk of the plunger deflecting, tilting, or jamming during SMA wire traction and spring reset, making the relative position between the plug and the valve vent more stable. Since there is a direct correlation between the effective opening of the vent and the plunger displacement, the stability of the plunger's movement direction and posture further improves the repeatability of vent flow control, thus benefiting pressure drop control during blood pressure measurement.

[0027] 4. Improve the airtightness of the valve body and the reliability of electrical connections.

[0028] This application incorporates a sealing protrusion and an optional rubber ring between the valve cover and valve base, achieving an airtight connection between the valve cover, valve base, and air pump via ultrasonic welding or adhesive bonding. Simultaneously, the two ends of the SMA wire are connected to a pin via terminals. The pin is fixed to an insulating base and passes through the valve cover, with the gap between the pin and the through-hole sealed by insulating sealant. This structure allows for the coordinated sealing of the valve cavity, the electrical connection of the SMA wire, and the insulating seal at the pin's exit point within the same component. This design reduces the risk of leakage points caused by electrical connections extending through the valve body and also lowers the possibility of poor contact between conductive components and moving parts within the valve cavity, thus improving the reliability of the component during long-term power-on / off cycles and repeated gas filling and releasing processes.

[0029] 5. Reduce the risk of plug seal failure and vent leakage.

[0030] This application places a plug at the end of the plunger facing the valve vent, which can be a rubber plug or an insulated elastic plug. Furthermore, a raised flexible spring can be provided on the side of the plug facing the valve vent. When the plunger moves towards the valve vent under the traction of the SMA wire, the plug or flexible spring can elastically fit against the inner edge of the valve vent. The elastic material can compensate for manufacturing tolerances of components, minor assembly deviations, and local unevenness at the edge of the valve vent, resulting in a more stable sealing contact when the vent is closed. This structure helps reduce problems such as insufficient pressure rise rate, unstable pressure maintenance, or increased pump load caused by micro-leakage at the vent during pressurization or pressure holding.

[0031] 6. Avoid interference between the plunger movement and the air pump outlet pipe.

[0032] This application features a through-pass intake channel on the plunger, designed in a racetrack shape, allowing the air pump outlet pipe to pass through the valve inlet and opening and reside within this intake channel. Furthermore, the length D of the intake channel along the plunger's sliding direction is greater than the plunger's maximum displacement d, ensuring that the intake channel always provides clearance for the air pump outlet pipe during reciprocating motion caused by SMA wire drive and spring return. This dimensional relationship reduces the risk of collision, friction, or jamming between the plunger and the air pump outlet pipe during plunger movement, while maintaining the air path connection of the air pump outlet pipe into the valve chamber unaffected by plunger movement, thus balancing compact pump-valve integration with reliable plunger movement.

[0033] It should be understood that all combinations of the foregoing concepts and the additional concepts described in more detail below can be considered part of the inventive subject matter of this disclosure, provided that such concepts do not contradict each other.

[0034] The foregoing and other aspects, embodiments, and features of the teachings of the present invention will be more fully understood from the following description in conjunction with the accompanying drawings. Other additional aspects of the invention, such as features and / or beneficial effects of exemplary embodiments, will become apparent from the following description or may be learned through practice of specific embodiments according to the teachings of the present invention. Attached Figure Description

[0035] The accompanying drawings are not drawn to scale. In the drawings, each identical or nearly identical component shown in the various figures may be denoted by the same reference numeral. For clarity, not every component is labeled in each figure. Embodiments of various aspects of the invention will now be described by way of example and with reference to the accompanying drawings, wherein:

[0036] Figure 1 This is an exploded view of the structure of a pump-valve integrated pneumatic control component based on a shape memory alloy valve, according to an embodiment of this application.

[0037] Figure 2This is a three-dimensional structural diagram of a pump-valve integrated pneumatic control component based on a shape memory alloy valve, as described in an embodiment of this application.

[0038] Figure 3 This is a structural diagram of a shape memory alloy valve at a first angle, representing a pump-valve integrated pneumatic control component based on a shape memory alloy valve in an embodiment of this application.

[0039] Figure 4 This is a structural diagram of a shape memory alloy valve from a second angle in an embodiment of the present application, representing a pump-valve integrated pneumatic control component based on a shape memory alloy valve.

[0040] Figure 5 This is an internal structural diagram of a shape memory alloy valve with a plunger, which is part of a pump-valve integrated pneumatic control component based on a shape memory alloy valve according to an embodiment of this application.

[0041] Figure 6 This is an internal structural diagram of a shape memory alloy valve without a plunger, which is part of a pump-valve integrated pneumatic control component based on a shape memory alloy valve according to an embodiment of this application.

[0042] Figure 7 This is a structural diagram of the plunger of a pump-valve integrated pneumatic control component based on a shape memory alloy valve, as described in an embodiment of this application.

[0043] Figure 8 This is a structural diagram of the valve cover of a pump-valve integrated pneumatic control assembly based on a shape memory alloy valve, according to an embodiment of this application, at a first angle.

[0044] Figure 9 This is a structural diagram of the valve cover of a pump-valve integrated pneumatic control assembly based on a shape memory alloy valve, as described in an embodiment of this application, from a second angle.

[0045] Figure 10 This is a schematic diagram of PID control for an integrated pump-valve pneumatic control component based on a shape memory alloy valve, as described in an embodiment of this application.

[0046] Figure 11 This is a schematic diagram of the first stage of the integrated pump-valve pneumatic control component based on a shape memory alloy valve in an embodiment of this application.

[0047] Figure 12 This is a two-stage schematic diagram of the integrated pump-valve pneumatic control component based on a shape memory alloy valve, as described in an embodiment of this application.

[0048] Figure 13 This is a schematic diagram of the three-stage integrated pump-valve pneumatic control component based on a shape memory alloy valve in an embodiment of this application.

[0049] Figure 14 This is a schematic diagram of the four-stage integrated pump-valve pneumatic control component based on a shape memory alloy valve in an embodiment of this application.

[0050] Figure 15 This is a schematic diagram of the five-stage integrated pump-valve pneumatic control component based on a shape memory alloy valve in an embodiment of this application.

[0051] Explanation of icon numbers:

[0052] 1. Air pump; 2. Valve cover; 201. Perforation; 202. Sealing protrusion; 203. Valve outlet; 204. First rib; 3. Valve outlet pipe; 4. Valve base; 401. Valve inlet; 402. Boss; 403. Fixing base; 5. Valve vent; 6. Plunger; 601. Limiting groove; 602. Inlet channel; 7. Plug; 8. SMA thread; 9. Terminal; 10. Spring; 11. Pin. Detailed Implementation

[0053] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art to which this invention pertains.

[0054] The terms "first," "second," and similar words used in the specification and claims of this patent application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, unless the context clearly indicates otherwise, the singular forms of "an," "a," or "the," etc., do not indicate a quantity limitation, but rather indicate the presence of at least one. Terms such as "comprising" or "including" mean that the element or object preceding "comprising" encompasses the features, integrals, steps, operations, elements, and / or components listed following "comprising" or "including," and do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or collections thereof. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; these relative positional relationships may change accordingly when the absolute position of the described object changes.

[0055] Existing electronic blood pressure monitors, especially oscillometric electronic blood pressure monitors, typically use an air pump to inflate the cuff and a valve body to release and regulate the pressure within the cuff, thus completing the pressurization, stabilization, and deflation measurement process. In existing technology, the air pump and valve body are usually separate units, connected by external air tubing, connectors, and other components to form a complete air circuit system; the valve body typically employs a proportional solenoid valve or other independently installed deflation valve structure.

[0056] The existing solutions described above have at least the following problems:

[0057] 1. In the split structure, the air pump, valve body and connecting air circuit are arranged separately. There are many connection nodes, sealing interfaces and intermediate air circuit volumes in the system, which makes the system structure complex. Moreover, the air circuit parameters are easily affected by factors such as pipeline length, pipe diameter, bending state, joint assembly state and pump-valve relative position, resulting in large uncertainties in pneumatic impedance, pressure transmission characteristics and dynamic response characteristics.

[0058] 2. In the product development process, the design of the external structure and the implementation of system functions in the existing split structure are highly coupled. Local changes in the structural design, such as adjustments to the pipeline layout, changes in connection methods, or changes in the valve body installation position, may cause changes in pressure control characteristics, resulting in fluctuations in system function. This makes the workload of whole-machine debugging, functional verification, and parameter correction large, which is not conducive to improving development efficiency and the standardization and reuse of testing methods, control strategies, and design experience.

[0059] 3. Existing proportional solenoid valves and other valve structures typically require separate configuration and corresponding drive methods to achieve gas regulation. Further optimization is needed for miniaturized, integrated, low-noise, and low-power applications. Especially in blood pressure measurement devices, if the air pump and valve body remain separate, system performance is more susceptible to changes in assembly conditions and structural layout, hindering improvements in product consistency, modularity, and platform development capabilities.

[0060] Therefore, there is an urgent need to provide a new pneumatic control structure to more tightly integrate the air pump and valve body, and to combine the driving characteristics of shape memory alloy valves to reduce the uncertainty of pneumatic parameters, reduce the sensitivity of system functions to the design and assembly status of peripheral structures, thereby improving the system consistency, engineering controllability and integration level of blood pressure measurement devices.

[0061] Therefore, embodiments of the present invention provide an integrated pump-valve pneumatic control component based on a shape memory alloy valve, referring to... Figure 1 and Figure 2 It includes an air pump 1 and a shape memory alloy valve that are airtightly connected. The shape memory alloy valve includes a valve base 4 and a valve cover 2 that is fitted onto the valve base 4 and airtightly connected thereto. The valve base 4 and the valve cover 2 form a valve cavity.

[0062] Reference Figure 3 and Figure 4 The valve base 4 has a valve vent 5 on its side that connects the inside and outside of the valve cavity; the bottom of the valve base 4 has a valve inlet 401 that connects the inside and outside of the valve cavity. The valve inlet 401 is located on one side of the valve cavity and has a boss 402 fixed thereon. The boss 402 has two second ribs protruding from it. An opening is provided between the two second ribs. When the air pump 1 is airtightly connected to the shape memory alloy valve, the air outlet pipe of the air pump 1 passes through the valve inlet 401 and the opening and is located inside the valve cavity.

[0063] Reference Figure 5 , Figure 6 and Figure 7 An insulated plunger 6 is slidably connected between two second ribs. The upper and lower surfaces of the plunger 6 have through air intake channels 602 to accommodate the air outlet pipe of the air pump 1 passing through the opening. A limiting groove 601 is provided on one side of the plunger 6 to accommodate the SMA wire 8. When the SMA wire 8 is energized and contracts, it pulls the plunger 6 toward the valve vent 5. Terminals 9 are respectively crimped to both ends of the SMA wire 8. A pin 11 is inserted into each terminal 9. Each pin 11 is individually fixed on an insulated fixed base 403 that protrudes from the inner bottom surface of the valve base 4. One end of the pin 11 is fixed inside the fixed base 403, and the other end passes through the valve cover 2. A plug 7 protrudes from the other end of the plunger 6 toward the valve vent 5. A spring 10 is sleeved on the plug 7, and one end of the spring 10 is fixed to the plunger 6, and the other end is fixed to the inner side wall of the valve base 4 to provide a restoring force to the plunger 6 away from the valve vent 5.

[0064] Reference Figure 8 and Figure 9 The top of the valve cover 2 is provided with a valve outlet 203 that connects the inside and outside of the valve cavity. The valve outlet 203 is airtightly connected to the valve outlet pipe 3 on the side facing away from the valve cavity. The top of the valve cover 2 is also provided with two through holes 201 that connect the inside and outside of the valve cavity and are adapted to the through positions of the two pins 11. The bottom of the valve cover 2 and the position that avoids the valve outlet 203 has a protruding first rib 204 to abut against the plunger 6.

[0065] Under the joint constraints of the valve base 4, boss 402, opening, air inlet channel 602 of plunger 6, and valve cover 2, the air outlet pipe of air pump 1 extends into the valve cavity and coexists with the moving structure of plunger 6. The structure utilizes the interaction of SMA wire 8 pulling plunger 6, spring 10 resetting plunger 6, and plug 7 sealing valve vent 5 to achieve the change in valve vent 5 opening degree with plunger 6 displacement. Since the contraction state of SMA wire 8 can be changed by electrical parameters, this structure has a basis for continuous or graded adjustment from closed to partially open and then to fully open. The first rib 204 and the second rib also cause plunger 6 to move in a predetermined direction within the limited valve cavity, thereby ensuring that the displacement generated by SMA wire 8 can be stably converted into a change in vent vent opening degree. Furthermore, the contact surface between the first rib 204 and plunger 6 can be polished smooth to achieve smooth sliding.

[0066] The air pump 1, valve base 4, and valve cover 2 form a compact, integrated air circuit structure, reducing the number of external connecting air pipes and connectors, and lowering the risk of air leakage and changes in pneumatic parameters due to assembly differences. The SMA wire 8, plunger 6, plug 7, and spring 10 form a valve port control mechanism that combines electric drive and mechanical reset, enabling the vent to close during pressurization, controlled venting during measurement, and rapid venting after measurement to be achieved within the same valve chamber. The plunger 6 inlet channel 602 avoids the air pump 1 outlet pipe, allowing the air pump 1 outlet path and the plunger 6 displacement path to be overlapped, which helps to reduce component size and improve pump-valve integration.

[0067] In some embodiments, reference is made to Figure 9 The valve cover 2 protrudes towards the valve cavity to form a sealing protrusion 202. The sealing protrusion 202 is inserted into the cavity formed by the inner sidewall of the valve base 4, and the outer contour of the sealing protrusion 202 is adapted to the inner sidewall contour of the valve base 4.

[0068] This design ensures that when the valve cover 2 is closed on the valve base 4, it not only forms a seal through the end face connection, but also achieves positioning and engagement with the inner wall of the valve base 4 through the sealing protrusion 202 extending into the valve cavity. Therefore, the assembly position between the valve cover 2 and the valve base 4 is defined, the boundary of the valve cavity is more stable, and the possibility of lateral misalignment of the valve cover 2 relative to the valve base 4 is reduced.

[0069] By concentrating the sealing and positioning functions on the sealing protrusion 202 on the inner side of the valve cover 2, the connection between the valve cover 2 and the valve base 4 no longer relies solely on the outer peripheral welded or bonded surfaces to ensure the valve cavity position. For a miniature valve body with an internal plunger 6, SMA wire 8, pin 11, and spring 10, a slight offset in the position of the valve cover 2 may affect the contact position between the first rib 204 and the plunger 6, and may also affect the protrusion position of the pin 11 and the position of the valve outlet 203. By adapting to the inner contour of the valve base 4, the sealing protrusion 202 allows the valve cover 2 to first form a geometric limit during the assembly stage, and then form an airtight connection, structurally improving the certainty of valve cavity assembly.

[0070] The sealing protrusion 202 serves as a guide, positioner, and auxiliary sealer during the assembly of the valve cover 2 and valve base 4, making it easier to maintain consistency in the valve cavity dimensions, the position of the first rib 204, and the position of the valve outlet 203. For integrated pump-valve pneumatic control components, the consistency of valve cavity dimensions and the position of moving parts within the valve affects the relationship between the vent opening and flow rate changes. This sealing protrusion 202 structure reduces the impact of valve cover 2 assembly deviations on the plunger 6 movement, valve port sealing, and pneumatic response, thereby improving component assembly quality and pneumatic control stability.

[0071] In some embodiments, a rubber ring is fitted around the outer contour of the sealing protrusion 202 to seal the assembly gap between the outer peripheral surface of the sealing protrusion 202 and the inner sidewall of the valve base 4.

[0072] An elastic seal is introduced to compensate for assembly gaps. When the valve cover 2 and valve base 4 are closed, the rubber ring is clamped between the outer periphery of the sealing protrusion 202 and the inner wall of the valve base 4, thus forming a circumferential seal on the valve cavity boundary. In the integrated pump-valve miniature valve cavity, the sealing protrusion 202 serves as the bearing base for the rubber ring, ensuring that the installation position of the rubber ring directly corresponds to the valve cavity opening. This structure differs from simply applying adhesive or welding to the end face of the valve cover 2 to form a seal. It compensates for manufacturing tolerances and assembly gaps through the elastic ring and works synergistically with the insertion positioning of the sealing protrusion 202. For valve bodies with SMA wire 8 and pin 11 protruding structures, this circumferential sealing structure improves the airtight reliability of the valve cavity body connection and makes it easier to form a complete sealing system for other protruding positions.

[0073] The rubber ring forms an elastic sealing interface between the valve cover 2 and the valve base 4, reducing the risk of air leakage caused by local discontinuities in the welded or bonded surfaces, differences in surface roughness, or assembly dimensional deviations. Since the blood pressure measurement process requires stability in cuff pressure changes, air leakage at the valve body connection affects the pressurization rate, pressure holding state, and deflation control accuracy. By incorporating the rubber ring, the airtightness of the valve cavity is enhanced, which helps improve the stability and consistency of the pneumatic control component during repeated inflation and deflation.

[0074] In some embodiments, the valve base 4 and the valve cover 2 are connected by ultrasonic welding or adhesive bonding to form an airtight connection between the valve base 4 and the valve cover 2.

[0075] A fixed connection is formed between the valve cover 2 and the valve base 4, which, together with the positioning and sealing function of the sealing protrusion 202, constitutes a closed valve cavity. Ultrasonic welding can form a fixed connection by melting local materials, while adhesive bonding can fill and fix the connection interface with adhesive. Both methods can be used for airtight connections of miniature plastic valve bodies or composite material valve bodies.

[0076] The sealing protrusion 202 first positions the valve cover 2, and then ultrasonically welds or adhesively fixes the valve cover 2 to the valve base 4, giving the valve body assembly process a clear structural reference and connection boundary. For valve bodies that internally contain a plunger 6 movement mechanism and a pin 11 protrusion structure, the valve cover 2 should not loosen due to air pressure changes or external vibrations after assembly. Ultrasonic welding or adhesive bonding enables the valve cover 2 and valve base 4 to form a stable mechanical bond, and cooperates with the sealing protrusion 202 to improve the overall sealing performance of the valve cavity. This connection method is suitable for the mass production of small pneumatic control components, which helps to reduce the occupation of component size and assembly space by additional fasteners such as screws and clips. At the same time, the fixedly connected valve cover 2 can stably restrict the vertical position of the plunger 6, ensuring that the limiting effect of the first rib 204 on the plunger 6 is consistent, thereby indirectly improving the stability of the plunger 6 sliding process and the valve vent 5 opening control.

[0077] In some embodiments, the valve base 4 is airtightly connected to the air pump 1 in the connection area surrounding the valve inlet 401 by ultrasonic welding or adhesive bonding.

[0078] This design establishes a mechanically fixed and airtight connection between the air pump 1 and the valve base 4. Combined with the structure where the air pump 1's outlet pipe passes through the valve inlet 401 and enters the valve cavity, the air output from the air pump 1 can directly enter the internal air passage of the shape memory alloy valve. Simultaneously, this design eliminates the need for a long external hose to form a connection path between the air pump 1 and the valve body; instead, it creates an integrated pump-valve structure through a local connection area of ​​the valve base 4. The connection method between the air pump 1 and the valve base 4 is specifically defined as a welded or bonded structure suitable for airtight integration, forming a combined air passage structure with the air pump 1's outlet pipe extending into the valve cavity. Traditional split-type air passages typically consist of the air pump 1 outlet, hose, connector, and valve body inlet connected sequentially, resulting in numerous connection interfaces. This application directly connects the air pump 1 to the valve base 4, fixing the starting section of the critical air passage inside the component or at the component connection surface. This reduces intermediate connecting parts between the air pump 1 and the valve body, facilitating the standardization of the pump-valve relative position, inlet path, and sealing interface.

[0079] After the valve base 4 is connected to the air pump 1 by ultrasonic welding or adhesive bonding, the connection strength and airtightness between the air pump 1 and the valve body are structurally guaranteed, reducing abnormalities caused by loose external hoses, leaking joints, and misaligned pipeline assembly. Since the distance and path from the output end of the air pump 1 to the valve cavity are fixed, the dynamic response of gas entering the valve cavity is more likely to remain consistent. This structure also facilitates the installation and testing of the air pump 1 and valve body as independent modules during product assembly, reducing the debugging complexity in overall machine development and mass production.

[0080] In some embodiments, each pin 11 is inserted into a corresponding through hole 201, and the gap between the pin 11 and the hole wall of the corresponding through hole 201 is sealed with insulating sealant.

[0081] Since the two ends of the SMA wire 8 are connected to the pin 11 through the terminal 9, and the pin 11 passes through the valve cover 2 and is electrically connected to the main board of the blood pressure monitor to supply power to the SMA wire 8, considering the structural feature of the pin 11 passing through the valve cover 2 from the inside of the valve cavity, insulating sealant is set at the point where the conductive part passes through the valve cover 2, so that the pin 11 can be electrically connected to the external circuit, while keeping the perforation 201 position airtight and insulated.

[0082] The pin 11 needs to be fixed to the insulating mounting base 403 of the valve base 4 and pass through the valve cover 2. If there is a gap between the perforation 201 and the pin 11, gas in the valve cavity may leak through this gap, and unstable contact may also form between the conductive part and the valve cover 2 or the external environment. This application uses insulating sealant to simultaneously handle airtightness and electrical insulation, making the electric drive structure of the SMA wire 8 compatible with the valve cavity sealing structure. The insulating sealant can fill the annular gap between the pin 11 and the perforation 201, blocking the path of leakage of gas from the valve cavity through the pin 11 and additionally fixing the pin 11. Since the SMA wire 8 needs to be repeatedly switched on and off, the stability of the pin 11 position will affect the reliability of the electrical connection; since the valve cavity needs to maintain pressure control, the sealing of the perforation 201 position will affect the pneumatic response. Through this design, the component can reduce the risk of leakage and short circuit while maintaining the convenience of external electrical connection, and improve the operational reliability of the pump-valve integrated pneumatic control component.

[0083] In some embodiments, the plug 7 is a rubber plug 7 or an insulating elastic plug 7 that elastically abuts against the inner edge of the valve vent 5.

[0084] For a miniature valve body driven by the SMA wire 8, the plunger 6 needs to close the vent within a short stroke. If the plug 7 is made of a hard material, manufacturing tolerances and assembly errors can easily lead to insufficient local contact at the valve port. By using rubber or an insulating elastic material, the plug 7 can form a more reliable contact seal with a shorter clamping stroke and make the contact process between the end of the plunger 6 and the valve port smoother. This material selection is compatible with the short-stroke driving characteristics of the SMA wire 8.

[0085] The rubber plug 7 or the insulating elastic plug 7 can compensate for minor deviations between the rim of the valve vent 5, the guide position of the plunger 6, and the installation position of the plug 7, reducing the risk of leakage in the closed state. During pressurization or pressure holding, the more stable the sealing effect of the vent, the less likely the gas output from the air pump 1 is to be lost through the vent, thus improving pressurization efficiency and pressure control stability. Simultaneously, the insulating elastic plug 7 can reduce the possibility of abnormal electrical contact between conductive components within the valve cavity and structures near the valve port, thus improving the safety and reliability of the electrically driven valve body.

[0086] In some embodiments, a flexible spring sheet is fixed to the side of the plug 7 facing the valve vent 5. The flexible spring sheet protrudes towards the valve vent 5 and elastically fits against the inner edge of the valve vent 5 when the plug 7 seals the valve vent 5.

[0087] Based on the elastic plug 7, a local flexible seal is further added, so that the sealing contact between the plug 7 and the valve vent 5 is achieved by the protruding elastic part facing the valve port. The flexible spring can first undergo local deformation when contacting the valve vent 5, and then form a covering and compression seal.

[0088] By setting a raised flexible spring on the end face of the plug 7, the sealing contact area of ​​the valve vent 5 has a stronger deformation adaptability. When the SMA wire 8 drives the plunger 6 to move, the plunger 6 has a small stroke and the driving force is affected by temperature and electrical parameters. If the seal requires a large amount of compression to achieve a seal, it will increase the driving burden. The raised flexible spring can contact the valve vent 5 with a small displacement first, and form a local compression by covering the edge of the port with the convex surface, reducing the dependence on the large stroke and large driving force of the plunger 6.

[0089] The flexible spring can further improve the sealing reliability of the valve vent 5 when closed and reduce the impact of local defects at the valve port edge on the sealing effect. Because the flexible spring has a raised structure, it can expand outwards to fit the edge of the valve vent 5 under pressure, which is beneficial for forming a continuous sealing contact. This structure can also reduce the impact of the overall material hardness of the plug 7, the guiding error of the plunger 6, or the machining error of the valve port on the sealing effect, thereby making the pressure build-up process in pressurization mode more stable and reducing the risk of measurement anomalies caused by micro-leakage at the vent port.

[0090] In some embodiments, spring 10 is a bias spring used to apply a reset bias force to plunger 6 in a direction away from valve vent 5.

[0091] A spring 10 is positioned between the plunger 6 and the valve base 4 as a biasing element opposing the SMA wire 8. When the SMA wire 8 is energized, it generates a contraction force, while the spring 10 provides an elastic force in the opposite direction. The position of the plunger 6 is determined by the force balance between the two. Through this opposing relationship, the plunger 6 can not only be in a fully closed or fully open position, but also remain in an intermediate position under certain conditions. This structure provides a mechanical basis for adjusting the vent opening and allows the valve vent 5 to return to the open state under the action of the spring 10 in the event of power failure.

[0092] The bias spring improves the reset reliability of the valve body under power failure or low current conditions, allowing gas in the bladder or cuff to be released through the valve vent 5, reducing the risk of the vent remaining closed due to drive failure. After the spring 10 and SMA wire 8 achieve force balance, the stop position of the plunger 6 can be adjusted by changing the drive electrical parameters of the SMA wire 8, resulting in different opening degrees of the vent. Therefore, this structure is beneficial for both safe venting and obtaining a controlled venting state during measurement, improving the controllability of the air pressure control process.

[0093] In some embodiments, when viewed from above, the air intake channel 602 is racetrack shaped. When the SMA wire 8 is not energized, the air outlet pipe of the air pump 1 is located at one end of the air intake channel 602 near the plug 7, and the outer contour of the air outlet pipe of the air pump 1 is adapted to the semi-circular end of the racetrack shape. The maximum displacement of the plunger 6 along the direction defined by the second rib is defined as d, and the length of the air intake channel 602 along the sliding direction of the plunger 6 is defined as D, then D > d.

[0094] To address the potential spatial interference between the air pump 1's outlet pipe extending into the valve cavity and the plunger 6 sliding within the valve cavity in the integrated pump-valve structure, a racetrack-shaped air intake channel 602 and its dimensional relationships are used to achieve structural avoidance. The end of the air intake channel 602 near the plug 7 is adapted to the outer contour of the air pump 1's outlet pipe, providing a positioning reference for the plunger 6's installation position in the initial state. Since the length of the air intake channel 602 along the sliding direction of the plunger 6 is greater than the maximum displacement of the plunger 6, it ensures that the plunger 6 does not experience hard interference with the air pump 1's outlet pipe within the drive displacement range of the SMA wire 8. This structure simultaneously satisfies the requirements of compact integration and motion reliability.

[0095] The racetrack-shaped air intake channel 602 provides clearance for the air pump 1's outlet pipe along the sliding direction of the plunger 6, allowing the air pump 1's outlet pipe to extend into the valve cavity without obstructing the reciprocating motion of the plunger 6. Since the movement of the plunger 6 directly determines the opening relationship between the plug 7 and the valve vent 5, friction or collision between the plunger 6 and the outlet pipe can lead to unstable opening control or even jamming. By limiting D to be greater than d, a safety margin for the plunger 6's movement throughout its entire stroke can be ensured from a dimensional perspective, thereby improving the manufacturability, assembly tolerance, and long-term operational reliability of the integrated pump-valve structure.

[0096] The following provides a specific example of blood pressure testing during the blood pressure control process based on SMA microfilaments:

[0097] Objective: To achieve air pressure control in a blood pressure measuring device using a shape memory alloy valve.

[0098] 0. Initial steps: Device initialization.

[0099] Read initial blood pressure: Before starting barometric pressure control, first initialize the measuring device to ensure that the system is working properly.

[0100] Device startup: Connect the connector 11 of this device to the main board of the blood pressure monitor, and connect the air pump 1 to the main board of the blood pressure monitor. Start the blood pressure monitor, activate the internal pressure sensor, and ensure that the data acquisition system and display interface are connected to record and display blood pressure data in real time.

[0101] 1. Start air pump 1: Inflation process. (Refer to...) Figure 11 ).

[0102] Air pump 1 and shape memory alloy valve start simultaneously: SMA wire 8 begins to heat up, and plunger 6 moves towards valve vent 5 under the energized contraction of SMA wire 8. Plug 7 blocks valve vent 5, thus closing it. Air pump 1 turns on, forcing gas into the cuff and initiating inflation. The system monitors pressure changes to ensure a stable inflation process. Figure 11 In the diagram, the blue dashed line on the left indicates the connection between the airbag, pressure sensor, and the device of this application (green indicates energized, gray indicates de-energized); the yellow and red arrows indicate the direction of gas flow; the table at the top right shows the function of this stage, and the data graph at the bottom right shows the waveform. Figures 12-15 The meanings expressed in the text are the same.

[0103] 2. Determine if the pressure exceeds the systolic pressure (high pressure). (Refer to...) Figure 12 ).

[0104] Check air pressure: During inflation, the system continuously monitors whether the air pressure inside the cuff has reached the preset systolic pressure (high pressure). If the air pressure exceeds the systolic pressure, the system will trigger the next step of deflation control.

[0105] 3. Linear exhaust (refer to) Figure 10 The preset range is 2 mmHg / s to 4 mmHg / s. (Refer to...) Figure 13 ).

[0106] Linear venting: When the air pressure exceeds the diastolic pressure, based on the existing PID control, the electrical parameters of the SMA wire 8 are adjusted, thereby controlling the temperature of the SMA wire 8, which in turn controls the opening degree of the valve vent 5, thus performing linear venting and ensuring that the air pressure decreases steadily within the range of 2mmHg / s to 4mmHg / s.

[0107] By adjusting the electrical parameters, the output force of the SMA wire 8 can be changed, creating different force balance states with the elastic force of the spring 10. This alters the position of the plunger 6 relative to the valve vent 5, further changing the effective flow area of ​​the valve vent 5. This change in effective flow area can be indirectly characterized by the change in the pressure drop rate.

[0108] The specific mechanism is as follows:

[0109] (1) Electrical parameters—mechanical response—displacement adjustment mechanism.

[0110] The SMA wire 8 generates a Joule heating effect when energized, and changes in the driving electrical parameters will change its output force; this output force is in opposition to the elastic force of the spring 10.

[0111] By adjusting the SMA drive electrical parameters, the following state can be achieved:

[0112] When the output force of SMA is greater than the elastic force of spring 10, the drive plunger 6 moves in the closing direction, causing the valve vent 5 to close.

[0113] When the two are in a state of force balance, the plunger 6 is located in the middle adjustment area, and the corresponding valve vent 5 is partially opened, thereby adjusting the pressure drop rate by changing the effective flow area.

[0114] When the output force of SMA is less than the elastic force of spring 10, the plunger 6 returns to its original position under the action of spring 10, causing the valve vent 5 to gradually or fully open.

[0115] This establishes a control relationship between the driving electrical parameters, SMA output force changes, plunger 6 position x changes, valve vent port 5 clearance h changes, valve vent port 5 effective flow area A changes, exhaust flow rate changes, and airbag pressure changes. This relationship can be verified through pressure feedback curves and changes in driving electrical parameters.

[0116] (2) Flow control mechanism based on changes in effective flow area.

[0117] The change in the position x of the plunger 6 will change the change in the gap h of the valve vent port 5 and the change in the effective flow area A of the valve vent port 5. The gas flow cross-sectional area will change accordingly, thereby forming an adjustable exhaust flow output.

[0118] (3) Unified control of multiple working modes.

[0119] Based on the above flow control mechanism, by adjusting the SMA drive electrical parameters, multiple pneumatic control modes can be achieved under the same valve structure:

[0120] ①Pressure mode (rapid pressure increase).

[0121] SMA wire 8 is energized to a driving state where the output force is greater than the restoring force of spring 10;

[0122] Piston 6 drives plug 7 to close valve vent 5;

[0123] Air pump 1 outputs gas into the airbag to achieve rapid pressurization.

[0124] ② Controlled venting mode (controlled descent).

[0125] Adjust the SMA drive electrical parameters to make the SMA output force and the spring force of spring 10 return to form a force balance;

[0126] The plunger 6 is in the middle adjustment zone, and the valve vent 5 is in a partially open state.

[0127] The deflation flow rate is matched with the change in airbag pressure, so that the airbag pressure decreases in a controlled manner within the target range.

[0128] During the controlled decompression phase, the rate of pressure decrease in the cuff or airbag is related to the exhaust flow rate Q and the equivalent volume V of the cuff or airbag, and can be approximately expressed as: Q≈V·|dP / dt|.

[0129] The exhaust flow rate Q of valve vent 5 is related to the effective flow area A of valve vent 5 and the pressure difference ΔP on both sides of the valve port, which can be summarized as: Q≈C·A·f(ΔP);

[0130] As the pressure of the cuff or airbag gradually decreases during the measurement process, the pressure difference across the valve vent 5 changes accordingly. Therefore, under the same effective flow area, the exhaust flow rate will also change with the pressure difference.

[0131] By adjusting the driving electrical parameters of the SMA wire to change the plunger position x, and further changing the effective flow area A of the valve vent 5, the relationship can be expressed as: change of SMA output force, change of plunger position x, and change of effective flow area A.

[0132] The controller calculates the pressure drop rate based on the real-time pressure collected by the pressure sensor. When the real-time pressure drop rate is greater than the target pressure drop rate, the controller increases the SMA wire drive electrical parameter, causing the plunger 6 to move towards the valve vent 5 and decreasing A. When the real-time pressure drop rate is less than the target pressure drop rate, the controller decreases the SMA wire drive electrical parameter, causing the spring 10 to push the plunger 6 back to its original position and increasing A. This allows the pressure inside the cuff or airbag to drop in a controlled manner within the target range.

[0133] The above formula is a simplified explanation of the control relationship. Specific parameters such as orifice diameter, current, PWM, and spring force are only used as test examples and are not intended as necessary limitations. Combining the air path parameters formed by the air pump 1 and the valve body structure in this application, a calibrable correspondence is established between the effective flow area of ​​the valve vent 5 and the exhaust flow rate, thereby achieving controlled regulation of the airbag pressure change rate through pressure feedback.

[0134] ③Rapid exhaust mode.

[0135] Cut off or reduce the SMA drive electrical parameters;

[0136] SMA wire 8 output force is reduced;

[0137] Under the action of spring 10, plunger 6 quickly returns to its original position;

[0138] The vent port 5 of the valve is fully opened, allowing for rapid gas release.

[0139] Unlike traditional solenoid valves that only perform open / close actions, this application uses the SMA drive electrical parameters in conjunction with the reset force of the spring 10 to make the effective flow area of ​​the valve vent 5 adjustable and coupled with the internal fixed air circuit to form a calibrable pneumatic response.

[0140] 4. Determine if the pressure is lower than the diastolic pressure (lower pressure). (Refer to...) Figure 14 ).

[0141] Determining if air pressure drops below diastolic pressure: During the exhaust process, the system determines if the air pressure is lower than the diastolic pressure (low pressure). If the pressure is lower than the diastolic pressure, the system will switch to rapid exhaust mode.

[0142] 5. Rapid exhaust. (Refer to...) Figure 15 ).

[0143] Rapid exhaust: If the gas pressure is lower than the diastolic pressure, the SMA wire 8 stops heating and returns to its initial state. The vent valve 5 will be fully opened to ensure rapid gas release.

[0144] 6. Blood pressure measurement complete: The measurement result is displayed.

[0145] The results show that after the device completes the measurement, it displays the final blood pressure value. The system collects data through a pressure sensor, outputs accurate blood pressure results, and provides data support for subsequent analysis.

[0146] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. A pump-valve integrated pneumatic control assembly based on a shape memory alloy valve, comprising an airtightly connected air pump and a shape memory alloy valve, characterized in that, The shape memory alloy valve includes a valve base and a valve cover that fits onto and is airtightly connected to the valve base, wherein the valve base and the valve cover form a valve cavity; The valve base has a valve vent on its side that connects the inside and outside of the valve cavity; the bottom of the valve base has a valve inlet that connects the inside and outside of the valve cavity. A boss is fixed on one side of the valve inlet, and two second ribs protrude from the boss. An opening is formed between the two second ribs. When the air pump is airtightly connected to the shape memory alloy valve, the air outlet pipe of the air pump passes through the valve inlet and the opening and is located inside the valve cavity. An insulated plunger is slidably connected between the two second ribs, and the upper and lower surfaces of the plunger are provided with through air intake channels to accommodate the air outlet pipe of the air pump passing through the opening; A limiting groove is formed on one side of the plunger to accommodate the SMA wire. When the SMA wire is energized and contracts, it pulls the plunger toward the valve vent. Terminals are crimped to both ends of the SMA wire, and a pin is inserted into each terminal. Each pin is individually fixed to an insulating base protruding from the inner bottom surface of the valve base. One end of the pin is fixed inside the base, and the other end passes through the valve cover. A plug protrudes from the other end of the plunger toward the valve vent. A spring is fitted onto the plug, with one end fixed to the plunger and the other end fixed to the inner side wall of the valve base, to provide a restoring force to the plunger away from the valve vent. The top of the valve cover has a valve outlet that connects the inside and outside of the valve cavity, and the valve outlet is airtightly connected to a valve outlet pipe on the side facing away from the valve cavity; the top of the valve cover also has two through holes that connect the inside and outside of the valve cavity and are adapted to the protrusion positions of the two pins; the bottom of the valve cover, in a position that avoids the valve outlet, has a first rib protruding to abut against the plunger.

2. The integrated pump-valve pneumatic control assembly based on a shape memory alloy valve according to claim 1, characterized in that, The valve cover protrudes towards the valve cavity to form a sealing protrusion. The sealing protrusion is inserted into the cavity formed by the inner wall of the valve base, and the outer contour of the sealing protrusion is adapted to the contour of the inner wall of the valve base.

3. The integrated pump-valve pneumatic control assembly based on a shape memory alloy valve according to claim 2, characterized in that, A rubber ring is fitted around the outer contour of the sealing protrusion to seal the assembly gap between the outer peripheral surface of the sealing protrusion and the inner sidewall of the valve base.

4. The integrated pump-valve pneumatic control assembly based on a shape memory alloy valve according to claim 2, characterized in that, The valve base and the valve cover are connected by ultrasonic welding or adhesive bonding to form an airtight connection.

5. The integrated pump-valve pneumatic control assembly based on a shape memory alloy valve according to claim 1, characterized in that, The valve base is airtightly connected to the air pump in the connection area surrounding the valve inlet by ultrasonic welding or adhesive bonding.

6. The integrated pump-valve pneumatic control assembly based on a shape memory alloy valve according to claim 1, characterized in that, Each of the pins is inserted into the corresponding hole, and the gap between the pin and the hole wall of the corresponding hole is sealed with insulating sealant.

7. The integrated pump-valve pneumatic control assembly based on a shape memory alloy valve according to claim 1, characterized in that, The plug is a rubber plug or an insulating elastic plug that elastically abuts against the inner edge of the valve vent.

8. The integrated pump-valve pneumatic control assembly based on a shape memory alloy valve according to claim 7, characterized in that, A flexible spring sheet is fixed to the side of the plug facing the valve vent. The flexible spring sheet protrudes towards the valve vent and elastically fits against the inner edge of the valve vent when the plug seals the valve vent.

9. A pump-valve integrated pneumatic control assembly based on a shape memory alloy valve according to claim 1, characterized in that, The spring is a bias spring, used to apply a reset bias force to the plunger in a direction away from the valve vent.

10. A pump-valve integrated pneumatic control assembly based on a shape memory alloy valve according to claim 1, characterized in that, When viewed from above, the air intake channel is racetrack shaped. When the SMA wire is not energized, the air pump's outlet pipe is located at the end of the air intake channel near the plug. The outer contour of the air pump's outlet pipe is adapted to the semi-circular end of the racetrack shape. Define the maximum displacement of the plunger along the direction defined by the second rib as d, and the length of the air intake channel along the sliding direction of the plunger as D, then D > d.

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