Aerosol suppression module for exhalation end of breathing machine

Abstract

The invention relates to the technical field of respiratory therapy equipment, in particular to an aerosol suppression module for the expiration end of a breathing machine. The aerosol suppression module for the expiration end of the breathing machine comprises a shell, a rectification structure, a multi-stage purification assembly, a negative pressure forming mechanism, a pressure sensing unit, a control unit and a safety interlocking mechanism. The negative pressure forming mechanism is in fluid communication with the outlet of the shell and is used for sucking gas in the negative pressure cavity so as to establish and maintain preset negative pressure in the negative pressure cavity; the pressure sensing unit is in fluid communication with the negative pressure cavity and used for collecting pressure signals in the negative pressure cavity in real time. The control unit is in signal connection with the pressure sensing unit, is electrically connected with the negative pressure forming mechanism and is used for adjusting the suction intensity of the negative pressure forming mechanism based on the pressure signal; the safety interlocking mechanism is associated with the shell and used for stopping suction of the negative pressure forming mechanism and allowing air flow to be passively discharged when it is monitored that a cover body of the shell is opened or a system abnormal signal is detected.

Description

Technical Field

[0001] This disclosure relates to the field of respiratory therapy equipment technology, and more particularly to an aerosol suppression module for the expiratory end of a ventilator. Background Technology

[0002] In recent years, non-invasive mechanical ventilation, invasive ventilation, and high-flow nasal cannulas have been widely used in clinical practice. Patients continuously expel aerosols containing high concentrations of pathogens through their expiratory end. Especially during infectious disease outbreaks, these expiratory aerosols significantly impact the safety of the healthcare environment, necessitating effective measures to reduce their escape and diffusion.

[0003] Current ventilators often reduce airflow velocity and some pathogen release by installing simple filters or diffuser caps, but these structures are mostly passive designs. Due to the lack of comprehensive control over airflow path, cavity pressure field, and respiratory phase, the jet airflow easily forms a high-momentum plume with a large aerosol diffusion radius. The filtration efficiency is easily affected by changes in flow velocity and resistance, and it cannot exert a stable inhibitory effect in the long term.

[0004] Furthermore, simply adding high-efficiency filters can increase expiratory resistance, thus affecting patient expiratory comfort and ventilation. How to effectively suppress aerosol escape and ensure system safety without significantly increasing expiratory burden is a pressing issue in current technology. Therefore, providing an expiratory end component capable of achieving preset negative pressure control and multi-stage purification synergy would have significant application value. Summary of the Invention

[0005] This disclosure provides an aerosol suppression module for the expiratory end of a ventilator, which at least solves the above-mentioned technical problems existing in the prior art.

[0006] The aerosol suppression module for the expiratory end of a ventilator provided in this disclosure includes: The housing has an inlet and an outlet, the inlet being used for an airtight connection with the outlet of the ventilator's exhalation valve, and a negative pressure chamber is formed inside the housing extending from the inlet to the outlet; A rectifier structure is disposed in the negative pressure cavity adjacent to the inlet, and is used to rectify the airflow entering from the inlet to form laminar flow; A multi-stage purification component is sealed and disposed downstream of the rectifier structure to divide the negative pressure chamber into an upstream region and a downstream region. The multi-stage purification component includes at least one stage particle filtration unit and a diffusion silencing unit arranged sequentially along the airflow direction. A negative pressure forming mechanism is fluidly connected to the outlet of the housing and is used to draw gas from the negative pressure cavity to establish and maintain a preset negative pressure in the negative pressure cavity. The pressure sensing unit is in fluid communication with the negative pressure cavity and is used to collect the pressure signal in the negative pressure cavity in real time. The control unit is connected to the pressure sensing unit and electrically connected to the negative pressure forming mechanism, and is used to adjust the suction intensity of the negative pressure forming mechanism based on the pressure signal. A safety interlock mechanism, associated with the housing, is used to stop the suction of the negative pressure forming mechanism and allow passive airflow discharge when the housing cover is detected to be open or a system malfunction signal is detected.

[0007] Furthermore, the negative pressure forming mechanism includes a miniature blower or a turbine suction unit disposed at the outlet of the housing. The control unit is electrically connected to the miniature blower or the turbine suction unit and is used to control the miniature blower or the turbine suction unit to maintain the preset negative pressure.

[0008] Furthermore, the negative pressure forming mechanism includes a Venturi ejector assembly, the air intake of which is in fluid communication with the negative pressure cavity. The Venturi ejector assembly is configured to generate the preset negative pressure in the negative pressure cavity by relying on the kinetic energy of the main airflow flowing through it. A pressure limiting orifice plate and an overflow bypass are provided on the air intake pipe of the Venturi ejector assembly.

[0009] Furthermore, the control unit is configured to receive the respiratory phase signal sent by the ventilator or the respiratory phase signal detected by the matching phase sensor, and establish a dual closed-loop control logic based on the pressure signal in the negative pressure chamber and the respiratory phase signal, so as to dynamically adjust the output of the negative pressure forming mechanism when the expiratory phase is detected, so as to make the expiratory resistance controllable and maintain stable airflow.

[0010] Furthermore, the multi-stage purification component also includes an ultraviolet sterilization unit, which is located downstream of the particulate filtration unit or integrated into the particulate filtration unit. The ultraviolet sterilization unit includes an ultraviolet light source facing the airflow channel and a sterilization chamber with a highly reflective inner wall surrounding the airflow channel, used to sterilize and inactivate the airflow passing through the area.

[0011] Furthermore, the shell wall is provided with a heating element, which is used to maintain the shell surface temperature above the dew point to reduce condensation, and the bottom of the shell is provided with a liquid collection tank, which is provided with a one-way drain valve to achieve directional discharge when the condensate reaches a preset liquid level.

[0012] Furthermore, the multi-stage purification component includes a quick-replaceable integrated filter element structure, and the safety interlock mechanism includes a sensing unit and an interlock circuit disposed on the housing for detecting the installation status of the filter element structure. The interlock circuit connects the sensing unit and the control unit and is used to prevent the negative pressure forming mechanism from starting when the filter element structure is not locked.

[0013] Furthermore, the safety interlock mechanism includes an over-negative pressure protection channel connecting the negative pressure chamber to the external environment and an electrical alarm module. The over-negative pressure protection channel is equipped with a pressure limiting valve. The pressure limiting valve is configured to automatically open to balance the pressure when the pressure in the negative pressure chamber is lower than a predetermined limit. The electrical alarm module is signal-connected to the pressure sensing unit and is configured to output alarm information when the pressure sensing unit detects an abnormal pressure.

[0014] Furthermore, the inlet of the housing is connected to the ventilator tubing via a standard interface, and an airflow diffusion grille is provided inside the housing on the outlet side of the multi-stage purification component to reduce airflow resistance and decrease dead space volume, thereby ensuring compatibility with different models of ventilators and maintaining low-noise operation.

[0015] The technical solution provided in this disclosure has the following advantages compared with the prior art: The aerosol suppression module for the expiratory end of a ventilator of the present invention significantly improves the infection protection performance of the expiratory end of the ventilator through the synergistic effect of negative pressure suction and multi-stage purification, while taking into account system stability, maintainability and safety.

[0016] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this disclosure, nor is it intended to limit the scope of this disclosure. Other features of this disclosure will become readily apparent from the following description. Attached Figure Description

[0017] The above and other objects, features, and advantages of this disclosure will become readily apparent from the following detailed description of exemplary embodiments, taken in conjunction with the accompanying drawings. Several embodiments of this disclosure are illustrated in the drawings by way of example and not limitation, in which: In the accompanying drawings, the same or corresponding reference numerals indicate the same or corresponding parts.

[0018] Figure 1 This is a schematic diagram of the structure and airflow path of an aerosol suppression module used in the expiratory end of a ventilator; Figure 2 A cross-sectional schematic diagram of a rectifier structure installed in a negative pressure cavity; Figure 3 This is a schematic diagram of the exploded structure of a multi-stage purification component. Figure 4AA schematic diagram of a suction system is shown. Figure 4B Another schematic diagram of the suction system is shown; Figure 5 This is a schematic diagram of the sensing and sampling arrangement system; Figure 6A Logic diagram for control and timing systems; Figure 6B This is a time-history overlay plot of an aerosol suppression module used in the expiratory end of a ventilator; Figure 7 This is a cross-sectional structural diagram of the condensation and drainage management system; Figure 8 This is a schematic diagram of a safety interlocking mechanism; Figure 9 The flow of secure interaction logic.

[0019] Explanation of the numbers in the diagram: 100, System; 102, Housing; 120, Negative Pressure Chamber; 130, Rectifying Structure; 140, Multi-stage Purification Components; 140a, Integrated Filter Structure; 141, Pre-filtration Unit; 142, HEPA Filter; 143, Electrostatic Capture Unit; 144, Electrical Interface Socket; 145, Sensor Interface; 150, Ultraviolet Sterilization Chamber; 151, UV-C Light Source; 152, High Reflectivity Surface; 153, Light-shielding Baffle; 160, Sound-absorbing Labyrinth; 160 1. Porous sound-absorbing layer; 170. Diffuser grille; 210. Blower; 212. PWM drive module; 214. Filter buffer chamber; 220. Venturi ejector; 221. Pressure limiting orifice plate; 222. Overflow bypass; 223. Throat; 224. Adjustable nozzle mechanism; 231. Safety valve; 232. Alarm circuit; 250. Buffer silencer duct; 302. Pressure tap; 310. Sensor unit; 311. Pre-filter sampling point; 312. Post-filter sampling point; 314. Pressure... Differential sensor; 316. Temperature and humidity sampling points; 317. Flexible micro-conduit; 320. Control module; 510. Zoned heating element; 511. Insulation layer; 520. Liquid collection tank; 521. One-way drain valve; 522. Chemical treatment chamber; 523. Gas-liquid separation structure; 524. Drainage pipeline; 525. Temperature sensor; 526. Liquid level sensor; 527. Splash shield; 528. Collection bottle; 529. Heating zone; 600. Control and timing system; 602. Control unit; 604, Pressure sampling module; 606, Respiratory phase signal input module; 608, PID controller; 610, Limiting protection module; 612, Abnormal return and interlocking module; 613, Phase correction module; 706, Light source module; 711, Sealing ring; 712, Filter box guide rail; 7121, Slide groove; 713, Buckle; 714, Elastic locking assembly; 720, RFID tag; 721, Safety interlocking mechanism; 731, Filter element differential pressure alarm device. Detailed Implementation

[0020] To make the objectives, features, and advantages of this disclosure more apparent and understandable, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0021] The aerosol suppression module for the expiratory end of a ventilator provided in this embodiment includes: a housing 102 having an inlet and an outlet, the inlet being for airtight connection with the outlet of the ventilator's expiratory valve, and a negative pressure chamber 120 extending from the inlet to the outlet being formed inside the housing 102; a rectifier structure 130 disposed within the negative pressure chamber 120 adjacent to the inlet for rectifying the airflow entering from the inlet to form laminar flow; and a multi-stage purification assembly 140 sealed downstream of the rectifier structure 130 for dividing the negative pressure chamber 120 into an upstream region and a downstream region, the multi-stage purification assembly 140 including at least one stage particle filtration unit and a diffusion unit arranged sequentially along the airflow direction. The system includes a sound unit; a negative pressure forming mechanism fluidly connected to the outlet of the housing 102, used to draw gas from the negative pressure chamber 120 to establish and maintain a preset negative pressure within the negative pressure chamber 120; a pressure sensing unit fluidly connected to the negative pressure chamber 120, used to collect pressure signals within the negative pressure chamber 120 in real time; a control unit 602 signal-connected to the pressure sensing unit and electrically connected to the negative pressure forming mechanism, used to adjust the suction intensity of the negative pressure forming mechanism based on the pressure signal; and a safety interlock mechanism 721 associated with the housing 102, used to stop the suction of the negative pressure forming mechanism and allow passive airflow discharge when the cover of the housing 102 is detected to be open or an abnormal signal from the system 100 is detected.

[0022] In some embodiments, the negative pressure forming mechanism includes a miniature blower or turbine suction unit disposed at the outlet of the housing 102, and the control unit 602 is electrically connected to the miniature blower or turbine suction unit to control the rotation speed of the suction unit to maintain a preset negative pressure.

[0023] In some embodiments, the negative pressure forming mechanism includes a Venturi ejector assembly, the air intake of which is in fluid communication with the negative pressure chamber 120. The Venturi ejector assembly is configured to form a preset negative pressure in the negative pressure chamber 120 by relying on the kinetic energy of the main airflow flowing through the Venturi ejector assembly. A pressure limiting orifice plate 221 and an overflow bypass 222 are provided on the air intake pipe of the Venturi ejector assembly.

[0024] In some embodiments, the control unit 602 is configured to receive a respiratory phase signal sent by the ventilator or a respiratory phase signal detected by a matching phase sensor, and establish a dual closed-loop control logic based on the pressure signal and respiratory phase signal in the negative pressure chamber 120, so as to dynamically adjust the output of the negative pressure forming mechanism when the expiratory phase is detected, so as to make the expiratory resistance controllable and maintain stable airflow.

[0025] In some embodiments, the multi-stage purification assembly 140 further includes an ultraviolet sterilization unit, which is disposed downstream of or integrated into the particulate filter unit; the ultraviolet sterilization unit includes an ultraviolet light source disposed toward the airflow channel and a sterilization cavity with a highly reflective inner wall disposed around the airflow channel for sterilizing and inactivating the airflow passing through the area.

[0026] In some embodiments, the wall of the housing 102 is provided with a heating element, which is used to maintain the surface temperature of the housing 102 above the dew point to reduce condensation, and the bottom of the housing 102 is provided with a liquid collection tank 520, which is provided with a one-way drain valve 521 to achieve directional discharge when the condensate reaches a preset liquid level.

[0027] In some embodiments, the multi-stage purification assembly 140 includes a quick-replaceable integrated filter element structure 140a, and the safety interlock mechanism 721 includes a sensing unit and an interlock circuit disposed on the housing 102 for detecting the installation status of the integrated filter element structure 140a. The interlock circuit connects the sensing unit and the control unit 602 and is used to prevent the negative pressure forming mechanism from starting when the integrated filter element structure 140a is not locked.

[0028] In some embodiments, the safety interlock mechanism 721 includes an over-negative pressure protection channel connecting the negative pressure chamber 120 to the external environment and an electrical alarm module. The over-negative pressure protection channel is provided with a pressure limiting valve. The pressure limiting valve is configured to automatically open to balance the pressure when the pressure in the negative pressure chamber 120 is lower than a predetermined limit. The electrical alarm module is signal-connected to the pressure sensing unit and is configured to output alarm information when the pressure sensing unit detects an abnormal pressure.

[0029] In some embodiments, the inlet of the housing 102 is connected to the ventilator tubing via a standard interface, and an airflow diffusion grille 170 is provided inside the housing 102 on the outlet side of the multi-stage purification component to reduce airflow resistance and reduce dead space volume, so as to ensure compatibility with different models of ventilators and maintain low-noise operation.

[0030] See Figure 1In some embodiments, the preset negative pressure multi-stage purification expiratory end system 100 for a ventilator provided by the present invention can be presented in the form of an isometric structural schematic, which shows the overall system layout, airflow path, and the interaction and correlation between the main components. System 100 may include, but is not limited to, a housing 102, a negative pressure chamber 120, a rectifying structure 130, a multi-stage purification assembly 140, a noise-absorbing diffusion channel, a suction unit (which may be a blower 210 or a Venturi ejector 220), and a sensor unit 310, a pre-filtration sampling point 311, and a post-filtration sampling point 312 (see reference). Figure 2 In the description of this invention, the term "suction unit" may also be referred to as "negative pressure forming mechanism," and the two are used interchangeably. In some cases, the direction of airflow can be controlled by... Figure 1 The central arrow indicates that gas enters from the ventilator's main unit outlet, flows sequentially through each component, and is finally and stably discharged into the external environment after uniform purification and rectification, thus achieving a safe and controlled exhaust effect. This invention is not limited to this schematic layout; the airflow path or component arrangement can be adjusted or optimized according to specific ventilator models and clinical usage environments.

[0031] In some embodiments, the housing 102 can be configured as a modular, closed structure for easy disassembly and maintenance according to different application requirements. Its inner wall is preferably made of a composite material or other functional material with low adsorption properties to reduce the residual adhesion of gaseous contaminants. Various types of interface adapters can be provided externally to achieve compatible connections with different models of ventilator tubing systems, such as standard 22 mm connector structures, 15 mm tubing structures, or other compatible sizes. The housing 102 has an inlet and an outlet, with the inlet configured for an airtight connection to the ventilator's expiratory valve outlet. The invention is not limited to these specific specifications. Inside the housing, a negative pressure chamber 120 is formed extending from the inlet to the outlet. This negative pressure chamber 120 can be configured to collect and guide the patient's expiratory airflow to effectively reduce the risk of aerosol leakage. Sealing rings and positioning flange structures can be provided around the chamber to reduce the risk of gas leakage. Sensor channels and maintenance ports can be provided in necessary areas, giving the system good maintainability and ease of testing.

[0032] In some embodiments, the negative pressure chamber 120 can be configured to maintain a preset negative pressure state inside the chamber via an external suction unit. The volume, cross-sectional shape, and streamline characteristics of the negative pressure chamber 120 can be optimized according to aerodynamic principles to buffer the incoming airflow and achieve a uniform diffusion distribution. Preset negative pressure control ensures that exhaled aerosols are preferentially guided into the chamber rather than escape into the environment, thereby effectively reducing the possibility of exhaled aerosol ejection. In addition, the negative pressure chamber 120 can be equipped with flow-limiting guide plates or flow-guiding elements to control the direction and distribution of airflow, allowing gas to be smoothly introduced into the multi-stage purification assembly 140. This invention is not limited to a specific internal structural form, and its design can be improved according to different negative pressure requirements and space constraints.

[0033] In some embodiments, the rectifier structure 130 can be disposed within the negative pressure chamber 120, adjacent to the inlet. The rectifier structure 130 is used to rectify the airflow entering from the inlet to form laminar flow, thereby reducing airflow turbulence, mitigating jet impact, and transforming random high-speed airflow into a smooth and uniform laminar flow state. In this embodiment, the rectifier structure 130 is shown as a rectifier honeycomb. However, those skilled in the art will understand that the rectifier structure is not limited to this, and can also employ any structure capable of suppressing turbulence, such as parallel guide vane groups, multi-layer microporous rectifier plates, grid arrays, or straight tube bundle rectifiers. The rectified airflow can be guided into the multi-stage purification assembly 140 located downstream. The multi-stage purification assembly 140 may include, but is not limited to, an electrostatic filtration unit, a HEPA filter, and an optional UV-C sterilization chamber. Depending on different application scenarios, the unit combination sequence and number of the multi-stage purification assembly 140 can be flexibly adjusted to balance improving filtration efficiency, reducing pressure drop, and extending maintenance cycles. In a preferred embodiment, this modular design gives the system good scalability and applicability to multiple scenarios.

[0034] It should be noted that although the rectifying structure 130 illustrated in this embodiment is a rectifying honeycomb, this is only one of the preferred embodiments. In other embodiments of the present invention, the rectifying structure 130 may also adopt other structural forms capable of suppressing turbulence and streamlining the flow field, including but not limited to: parallel guide vane groups, multi-layer microporous rectifiers, grid arrays, or straight tube bundle rectifiers, etc. Any structure that can weaken the jet impact and make the airflow tend to be uniformly distributed at the inlet of the negative pressure cavity 120 is covered within the protection scope of the "rectifying structure" of the present invention.

[0035] Optionally, a noise-absorbing diffusion channel (noise-absorbing labyrinth 160) can be provided downstream of the multi-stage purification component 140. This noise-absorbing diffusion channel can adopt a porous diffusion structure, a zigzag labyrinth structure, or any other suitable noise-absorbing diffusion form to further slow down the airflow velocity and reduce exhaust noise. Through this noise-absorbing diffusion channel, the exhaust airflow can be redistributed to a larger cross-sectional area, thereby allowing the gas to diffuse and be released into the external environment in a smooth manner at the outlet end. A diffusion grid or other flow equalization element can also be provided at the end of the channel to prevent local high-speed jets, further ensuring the slow-release effect of the airflow and improving the overall comfort and safety of the system operation. This invention is not limited to a specific channel structure or material configuration.

[0036] In some embodiments, the suction unit (i.e., the negative pressure forming mechanism) can take various forms. For example, the suction unit can be an independent electrically controlled blower 210 located at the outlet of the housing 102 to maintain a target preset negative pressure state within the cavity, or it can be as follows: Figure 4A The diagram shows a Venturi ejector 220 based on aerodynamic effects, which achieves airflow drive by utilizing the main airflow of the ventilator to create an incidental suction effect. In some combined embodiments, the blower 210 and the Venturi ejector 220 can also work together to obtain a wider operating range or redundancy, thereby enhancing the reliability of the system 100. The suction unit is in fluid communication with the outlet of the housing 102, configured to suction gas within the housing 102, and can adjust the suction intensity in real time according to the signal output by the control unit 602 to maintain stable airflow characteristics within the system.

[0037] In some embodiments, system 100 may include multiple sensor units 310, pre-filter sampling points 311, and post-filter sampling points 312 (e.g., ...). Figure 2 As shown, the sensor unit 310 is used for real-time detection and control of key parameters inside the cavity. Multiple sensor units 310 can be installed on the top, bottom, and sides of the housing 102. The sensor unit 310 includes a cavity pressure sensor, which is fluidly connected to the negative pressure cavity 120 and can be used to collect pressure signals within the negative pressure cavity 120 in real time to ensure a constant negative pressure within the cavity. A differential pressure sensor 314 can be used to measure the pressure drop across the multi-stage purification assembly 140 (filter element), thereby assessing the degree of clogging and service life of the filter element in the multi-stage purification assembly 140. In some embodiments, a temperature and humidity sensor can be used to monitor the temperature and humidity status of the environment inside the negative pressure cavity 120, and combined with a control algorithm to assist in condensation suppression and system stability improvement. All signals collected by the sensors can be transmitted to the control unit 602 (which is signal-connected to it) for comprehensive calculation. The control unit 602 is electrically connected to a blower or ejector control valve, and by adjusting the blower speed or ejector airflow intensity, dynamic balance and intelligent control are achieved.

[0038] The sensor unit 310 also includes a temperature sensor and a humidity sensor.

[0039] like Figure 1 As shown, in some embodiments, the airflow path may include multiple continuous functional segments, forming a mainstream path from the ventilator's expiratory valve outlet to the negative pressure chamber 120 inlet, and finally exiting through the rectifier structure 130, multi-stage purification components 140, and a noise-absorbing diffusion channel to form a purified exhaust path. This pneumatic path can constitute a closed and continuous airflow transmission link, ensuring that all exhaled gases undergo necessary control, guidance, and multi-stage purification before being discharged into the environment. In different embodiments, the system 100 can be directly installed into the ventilator housing via a flange interface, or it can be fabricated as an independent module and connected to the main unit via a hose, thus giving the system flexibility and versatility in structure and application.

[0040] In some embodiments, the outer surface of the housing 102 may preferably be made of a material with easy disinfection properties or an antibacterial coating to improve hygiene and safety in clinical environments. The internal sealing structure may utilize high-temperature resistant silicone rings, medical-grade EPDM, or other compatible materials to ensure long-term sealing stability. The interface design can select different connection standards according to different types of accessories, such as 22 mm or 15 mm connection forms, and both can be configured with removable seals for easy disinfection and replacement maintenance. The overall structure of the system 100 provided by this invention has a highly modular feature, making it usable as an original equipment manufacturer (OEM) component for ventilators, or as an aftermarket module that can be independently installed on various existing ventilators, thereby significantly improving the device's practicality, adaptability, and market versatility.

[0041] In some embodiments, Figure 2 The negative pressure chamber shown is Figure 1 Another cross-sectional view of the negative pressure chamber 120 is shown to visually illustrate the overall geometry of the chamber, the internal airflow path, and the spatial relative positions of key components. The negative pressure chamber 120 can be constructed as a closed space with a certain volume; for example, in a non-limiting example, its volume may be in the range of hundreds of milliliters, to ensure sufficient diffusion and stable airflow. Preferably, the length direction of the negative pressure chamber 120 is substantially consistent with the direction of the airflow channel to reduce flow loss caused by directional deviation. In some preferred embodiments, the inlet end of the negative pressure chamber 120 can be fluidly connected to the expiratory valve of the ventilator, while the outlet end can be connected to the multi-stage purification assembly 140. The inlet and outlet portions can respectively adopt a conical convergent and expandable transition structure to achieve a balance between pressure drop and flow field uniformity within a certain range. The cone angle design can be selected as needed; for example, in some cases it can be within a moderate range to optimize airflow guidance performance, which is not limited in this invention.

[0042] In some embodiments, the inner surface of the negative pressure chamber 120 can be coated with a material possessing anti-condensation properties, such as an anti-condensation layer based on polytetrafluoroethylene (PTFE) or other fluorinated polymer materials with low surface energy. This effectively inhibits the adhesion of aerosols or condensate to the wall surface during operation, preventing interference with local airflow distribution due to condensation. Such anti-condensation coatings also help reduce droplet retention on the chamber wall, working in conjunction with a collection tank that can be installed at the bottom of the negative pressure chamber 120 to achieve automated drainage and condensation management. In some embodiments, to ensure the chamber maintains good airtightness and anti-fouling performance under long-term use, its main structure can be made of materials with electrical and mechanical stability, such as antistatic ABS, polycarbonate, or a composite material with an aluminum alloy lining. Those skilled in the art should understand that the specific material selection can be flexibly adjusted according to the actual usage environment, cost constraints, and temperature tolerance requirements; this invention does not limit this selection.

[0043] In some embodiments, a flow-rectifying structure 130 may be provided inside the inlet region of the negative pressure chamber 120. This structure can be used to reduce the turbulence of the airflow injected from the exhalation valve and help establish a uniform axial flow pattern. The flow-rectifying structure 130 may be composed of a honeycomb array of multiple small channels. The geometric parameters of each channel can be flexibly designed according to performance requirements. For example, the aperture and aspect ratio of the channel can be designed to vary within a certain range to ensure a high porosity and low flow resistance loss. With this structural configuration, the pressure drop of the honeycomb section can be controlled within a reasonable range under rated operating conditions, thereby effectively reducing jet eccentricity and the generation of secondary vortices. In some illustrative examples, the flow-rectifying structure 130 may be made of flame-retardant polypropylene, anodized aluminum, or reinforced paper honeycomb material. The specific material selection can be flexibly determined according to the usage environment, cost, and mechanical strength requirements, and is not limited to the examples described above.

[0044] In this embodiment, the rectifying structure 130 can be installed in the corresponding area of ​​the inner wall of the negative pressure chamber 120 through a sealing ring, a slot, or other equivalent fixing method, and can optionally be axially aligned with the ventilator's exhalation valve port through structural elements such as positioning shoulders and guide rings. To ensure stable airflow guidance, the geometric center line of the rectifying honeycomb is preferably substantially coincident with the overall axis of the chamber, so that the airflow can maintain a near-laminar flow pattern after passing through the rectifying honeycomb section, thereby reducing flow field separation and reducing local pressure drop concentration. A smooth transition structure, such as an arc-shaped or gradually expanding transition channel, can be set in the downstream region of the rectifying honeycomb section to further guide the airflow to the area before the filter element, providing a more stable and uniform airflow input for the downstream multi-stage purification component 140. This installation structure of the present invention not only enhances assembly robustness but also improves the synergistic performance of system rectification and filtration.

[0045] To achieve accurate pressure sampling and control monitoring, such as Figure 2 As shown, in some embodiments, a pressure tap 302 may be provided at the center of the negative pressure chamber 120, which can be connected to a chamber pressure sensor via a conduit for real-time measurement of the negative pressure value inside the negative pressure chamber 120 during testing or operation. The geometry of the pressure tap 302 can be adjusted according to the required range and response speed to achieve rapid pressure response without significantly disturbing the streamline of the main flow channel. In a further embodiment, pre-filter sampling points 311 and post-filter sampling points 312 can be respectively set in the upstream and downstream regions of the rectifier structure 130, and the pressure difference between them can be detected by a differential pressure sensor 314 system, thereby deriving the resistance change of the multi-stage purification component 140 (filter element) and realizing online monitoring of the service life of the filter element in the multi-stage purification component 140 and the aerodynamic stability of the system. This coordinated design of pressure tapping and sampling layout helps to form closed-loop control and improve the steady-state operation performance of the overall system.

[0046] In some embodiments, to enhance the response stability of the negative pressure chamber 120 under different expiratory flow rate variations, the ratio of the inner diameter between the inlet and outlet of the negative pressure chamber 120 can be designed to be close to a unit ratio range based on the principle of airflow resistance balance, thereby ensuring the continuity of the flow velocity distribution. The internal transition section can have a geometric configuration with smooth curvature changes, such as a gradually changing structure of circular arc or parabola, to avoid backflow and the formation of vortex regions caused by rapid expansion or contraction. Through fluid dynamics simulation and parameter optimization, the streamline distribution inside the chamber can be made more uniform, and its turbulent kinetic energy can be maintained at a low level, thereby reducing the risk of aerosol sedimentation and ensuring the overall balance of negative pressure inside the chamber. This structural design enables the negative pressure chamber 120 to respond quickly to expiratory phase pressure fluctuations and maintain a stable airflow contraction state at the end of expiration, thereby assisting in the efficient adsorption of aerosols and flow field rectification. This invention does not limit this aspect.

[0047] In another embodiment, a temperature detection unit can be installed on the outer surface of the negative pressure chamber 120 and connected to the system control module 320 to achieve real-time monitoring and adjustment of the shell surface temperature, maintaining it within a certain range above the air dew point, thereby suppressing condensation. This temperature control function can form a synergistic working mechanism with the aforementioned anti-condensation coating to further improve the overall anti-condensation performance. For ease of maintenance, the negative pressure chamber 120 may optionally be equipped with a threaded inspection hole or a quick-release end cap structure to facilitate periodic cleaning of the rectifier structure 130 or the pressure tapping components. In long-term operation scenarios, the system control unit 602 can also automatically adjust the suction intensity based on real-time chamber pressure data and differential pressure signals, adapting to different environmental humidity conditions, so that the chamber continues to operate within a preset negative pressure range, thereby improving the system's reliability and adaptability.

[0048] In this embodiment, the control unit 602 includes a control module 320.

[0049] In conclusion, Figure 2 The structure shown defines the geometric parameters and hydrodynamic relationships between the negative pressure chamber 120 and its rectifying structure 130, providing a feasible technical path for airflow rectification, pressure sampling, and subsequent control. During the overall system operation, the spatial arrangement of the rectifying honeycomb structure section and the pressure tapping orifice works synergistically, enabling the chamber pressure sensor to accurately reflect the dynamic changes in air pressure within the chamber, thereby ensuring the accuracy of closed-loop control. Simultaneously, the rational layout of the pre-filter sampling point 311 and the post-filter sampling point 312 provides crucial data support for the efficiency evaluation and resistance monitoring of subsequent purification units, demonstrating the comprehensive technical advantages of this invention in maintaining preset negative pressure, aerodynamic stability, and automated monitoring at the system level.

[0050] See Figure 3 In some embodiments, the multi-stage purification assembly 140 of the present invention can be configured to be shown in the form of an exploded view or a partial sectional view, thereby more clearly presenting the various filtration units and their installation relationships. The multi-stage purification assembly 140 can generally be located downstream of the negative pressure chamber to form the main purification path through which the exhaled airflow passes. In specific implementations, the multi-stage purification assembly 140 may include, but is not limited to, a pre-filtration unit 141, a final filtration unit HEPA filter 142, an electrostatic capture unit 143, and an optional ultraviolet sterilization chamber 150 (also referred to as an ultraviolet sterilization unit). The above units can be sealed by the cooperation structure of the sealing ring 711 and the filter box guide rail 712, dividing the negative pressure chamber 120 into an upstream and downstream area, allowing the airflow to completely pass through the predetermined channel and effectively preventing bypass leakage. In some optional embodiments, a sound-absorbing labyrinth and diffusion grille 170 can also be provided on the right side of the multi-stage purification assembly to further attenuate noise and balance the flow field diffusion after the airflow has been purified, thereby improving the stability and quietness of the system operation. In some embodiments of the present invention, the pre-filtration unit 141, the HEPA filter element 142, and / or the electrostatic capture unit 143 can be collectively referred to as a particulate filtration unit; the silencing labyrinth 160 and the diffusion grid 170 and the silencing diffusion channel they form can be collectively referred to as a diffusion silencing unit. The multi-stage purification assembly includes at least one particulate filtration unit such as the pre-filtration unit 141, the HEPA filter element 142, and a diffusion silencing unit such as the silencing labyrinth 160, arranged sequentially along the airflow direction.

[0051] In some embodiments, the pre-filtration unit 141 can be configured as a replaceable coarse filtration assembly, which may include, but is not limited to, filter cotton or fiber mesh structures, for preliminary interception and separation of larger particles and liquid droplets in the incoming airflow. The pre-filtration unit 141 is preferably located in the airflow inlet region, and its material composition and thickness can be flexibly configured according to the desired flow rate, dust holding capacity, and resistance characteristics. For example, under certain typical conditions, the pre-filtration unit 141 may employ a porous polyester fiber pad covered with a hydrophilic coating to effectively block and adsorb droplets while preventing their penetration; a flow guide grid may be provided in the downstream region to ensure uniform distribution of airflow across the entire filtration cross-section. The mounting frame of the pre-filtration unit 141 can be embedded into the module filter box guide rail 712 via a snap-fit ​​interface, and the sealing ring 711 ensures that the airflow flows only along the designed path, thereby preventing bypass phenomena.

[0052] In another embodiment, the electrostatic capture unit 143 can be arranged downstream of the pre-filtration unit 141 to capture submicron-sized aerosol particles and other fine suspended impurities through an electrostatic field. The electrostatic capture unit 143 may include alternating dust collection and discharge electrodes, and its power supply module may optionally be external to the main control circuit to reduce potential interference from the high-voltage electric field to other control units. The frame structure of the electrostatic capture unit 143 can cooperate with the filter cartridge guide rail 712 to form a multi-stage purification assembly 140. An electrical interface socket 144 can be provided within the frame of the electrostatic capture unit 143 to enable quick connection and disconnection of the electrostatic capture unit 143. In some embodiments, the electrostatic capture unit 143 and the downstream HEPA filter element 142 can work together to improve overall particulate matter removal efficiency and reduce the filtration load on the HEPA filter element, thereby extending system maintenance cycles and maintaining smooth airflow.

[0053] In some embodiments, the HEPA filter element 142 is preferably positioned midway within the multi-stage purification assembly 140 to achieve efficient removal of particles with a diameter greater than or equal to approximately 0.3 micrometers. The pleat depth and fiber layer density of the HEPA filter element 142 can be comprehensively optimized according to the flow rate and pressure drop parameters set by the system to maintain airflow resistance within a reasonable range. The outer frame of the HEPA filter element 142 can be clamped between the filter box guide rails 712 by sealing rings 711 on both sides, thereby forming a sealed airflow path and preventing leakage. For ease of maintenance, the HEPA filter element 142 can adopt a modular drawer-type design, allowing for direct removal of the corresponding tray for replacement when needed. In some optional embodiments, the HEPA filter element 142 may be provided with positioning flanges and limiting latches to ensure accurate and reliable assembly positioning and prevent displacement or misalignment caused by vibration.

[0054] In some embodiments, the UV sterilization chamber 150 can serve as an optional functional unit downstream of the HEPA filter (i.e., located downstream of or integrated into the particulate filter unit). Multiple UV-C light sources 151 can be disposed within the UV sterilization chamber 150, with a radiation wavelength range of, but not limited to, 265 to 280 nanometers. To improve light energy utilization, the UV-C light sources 151 are oriented towards the airflow channel, and a portion of the inner wall of the UV sterilization chamber 150 can form a highly reflective surface 152 surrounding the airflow channel, thereby enhancing light reflection and irradiation uniformity. A light-shielding baffle 153 can be disposed at the outlet of the UV-C light source 151 to prevent direct leakage of ultraviolet rays. The baffle can be a folded-back structure design to effectively shield light while maintaining unobstructed airflow. The UV-C light source 151 can be mounted on a metal heat sink substrate and electrically connected to the main control unit 602 via an electrical connection cable for UV-C light source 151 status monitoring and safety interlock control. The interface areas at both ends of the UV sterilization chamber 150 and the adjacent filter element (such as HEPA filter element 142) can be airtightly connected through the sealing ring 711, thereby ensuring effective isolation between the UV irradiation chamber and the air channel and preventing leakage of UV light or airflow.

[0055] In an optional embodiment, the outer shell of the ultraviolet sterilization chamber 150 can be made of a metal-plated aluminum material with high reflectivity or a composite reflective coating structure to improve reflection efficiency and reduce light source energy consumption. The length and internal structure of the ultraviolet sterilization chamber 150 can be flexibly adjusted according to the required ultraviolet irradiation dose and airflow residence time, thereby ensuring that the air passing through the ultraviolet sterilization chamber 150 receives sufficient UV-C irradiation time at a set flow rate to complete the microbial inactivation process. To further improve system safety, an open-lid detection component can be installed on the outer shell of the multi-stage purification component 140, so that when the multi-stage purification component containing the ultraviolet chamber is detected to be in an open or disassembled state, the control circuit can automatically cut off the power supply to the UV-C light source 151 and delay shutting down the fan or suction unit to prevent ultraviolet radiation leakage and the risk of accidental aspiration. This design of the present invention enhances the safety and reliability of the equipment.

[0056] In the outlet region of the multi-stage purification component 140, a silencing labyrinth 160 can be provided, forming an airway structure with a zigzag path inside. This structure is used to attenuate noise and smoothly discharge airflow through sound-absorbing material layers and geometric flow channel design. In some embodiments, the inner wall of each channel of the silencing labyrinth 160 can be lined with a porous sound-absorbing layer 1601, the material of which may include, but is not limited to, polyurethane foam or a film-coated porous fiber layer, and the thickness can be adjusted according to the noise characteristics of the target frequency band. The silencing labyrinth 160 and the diffusion grille 170 disposed downstream together constitute an airflow energy dissipation zone, allowing the gas purified through the multi-stage purification to be discharged at a reduced speed and with a smooth distribution. The diffusion grille 170 is located on the outlet side of the multi-stage purification component 140 and can be configured in the form of a porous array or gradually expanding blades to further improve the uniformity of airflow distribution and reduce residual aerodynamic noise, thereby optimizing the overall noise control effect.

[0057] In another embodiment, to improve the ease of installation and removal and sealing reliability of the multi-stage purification component 140, the filter box guide rail 712 can form a groove 7121 along the inner wall of the multi-stage purification component 140, and each functional unit can be sequentially embedded and positioned along the groove 7121. The combined structure of the groove 7121 and the sealing ring 711 ensures that when adjacent units are pressed into place, their sealing surfaces can effectively fit together to form a continuous airtight path. The filter box guide rail 712 may further include limiting elements and positioning stops to prevent the component from misaligning or loosening due to vibration during operation. The sealing ring 711 can be made of medical-grade silicone rubber or EPDM material, thereby providing excellent elastic recovery performance and UV aging resistance. Through this modular design, the maintenance cycle can be flexibly determined based on differential pressure monitoring or life detection signals, and the replacement operation is simple and quick, thereby effectively reducing the workload of clinical maintenance and improving the sustainable operation of the system.

[0058] In some embodiments, each unit of the multi-stage purification component 140 may also integrate multiple sensor interfaces 145 for real-time monitoring of the pressure difference before and after filtration, the temperature of the ultraviolet sterilization chamber, and other operating parameters. The monitoring signals can be transmitted to the system control unit 602 for dynamic assessment of the filter element's status and operational safety. For example, when the pressure difference across the filter element exceeds a set threshold, the control unit 602 can issue a filter element replacement reminder; when the ultraviolet light source temperature or cumulative operating time exceeds a predetermined value, it can issue a maintenance reminder to maintenance personnel. Through the aforementioned sensing and feedback mechanisms, the multi-stage purification component 140 can not only achieve efficient air purification and microbial inactivation but also realize intelligent self-diagnosis, maintenance reminders, and safety interlock control, thus adapting to the long-term, stable, and demanding operation scenarios in hospitals and other medical environments.

[0059] In some embodiments, the present invention illustrates a functional structural comparison of two alternative negative pressure generation and suction implementation schemes. For example... Figure 4AAs shown, an active micro blower 210 closed-loop suction system can be used, and Figure 4B The figure shows a passive suction system based on a Venturi ejector 220. Both approaches establish and maintain the required preset negative pressure environment within the negative pressure chamber 120 through different pneumatic drive principles, thereby stabilizing and controlling the expiratory airflow and effectively suppressing aerosol escape. In some exemplary embodiments, the arrows in the figure may indicate the airflow direction, and the typical operating pressure range within the chamber may vary in practical applications. 5 to The present invention does not limit the range of fluctuations within 20 Pa or other suitable preset negative pressure ranges.

[0060] In some embodiments, the miniature blower 210 can be configured as an independent pneumatic drive component, with its inlet connected to the outlet of the negative pressure chamber 120, and its exhaust outlet connected to the external environment or the negative pressure discharge system within the hospital via a buffer silencer duct 250. In some embodiments, the operating state of the blower 210 can be controlled by the PWM drive module 212 and adjusted through closed-loop feedback formed with the output signal of the sensor unit 310 (chamber pressure sensor). Control strategies may include, but are not limited to, employing PID algorithms, fuzzy logic algorithms, or other suitable closed-loop control mechanisms to enable the system to respond to changes in the patient's expiratory flow rate during the expiratory phase, thereby maintaining the stability of the target pressure zone. To prevent excessive suction leading to high negative pressure, a pressure limiting protection mechanism can be set. When the chamber pressure falls below a preset safety threshold, such as below a specified negative pressure level, the control module 320 can automatically reduce the PWM duty cycle, limit the blower speed, or disconnect the power supply to ensure safe system operation. Relevant parameters can be flexibly adjusted according to actual operating conditions.

[0061] In some embodiments, the Venturi ejector 220 can generate a secondary suction effect by utilizing the aerodynamic characteristics of the main ventilator airflow passing through it at high speed. Its core nozzle portion can form a throat 223 with a throttling effect, increasing the flow velocity and creating a localized negative pressure through the geometric contraction of the conduit. This negative pressure signal can be fluidly connected between the inlet of the Venturi ejector assembly and the negative pressure chamber 120 via a branch conduit, thereby achieving a natural suction function without the need for additional motors or drive components. To ensure safety and stability, a pressure-limiting orifice plate 221 and an overflow bypass 222 can be provided on the inlet conduit of the Venturi ejector 220 to automatically divert some gas when the main airflow changes drastically, preventing excessively high negative pressure peaks. The orifice diameter of the pressure-limiting orifice plate 221 and the cross-sectional area parameters of the overflow bypass 222 can be set in some embodiments based on the flow rate characteristic curve and calculation analysis results, or determined through experimental optimization to ensure that the chamber pressure remains essentially constant within a tolerable range. This invention does not impose specific limitations on this design.

[0062] In some embodiments, the closed-loop control system formed by the blower 210 offers superior performance in terms of pressure regulation accuracy and controllability compared to the Venturi ejector structure, making it particularly suitable for devices requiring high performance or reusability. The passive solution of the Venturi ejector 220, due to its simple structure and low cost, is suitable for single-use or cost-sensitive applications. Both solutions can be further integrated with the communication interface of the main control unit 602 to achieve the output and unified display of real-time chamber pressure, airflow, and alarm signals, thereby realizing comprehensive monitoring and safety recording of overall system parameters. In some composite system architectures, the blower 210 can also serve as the main suction source, while the Venturi ejector 220 plays an auxiliary stabilizing role, forming a negative pressure suction system with multi-layered redundancy, thereby improving the overall system reliability.

[0063] In some embodiments, a filter buffer chamber 214 may be provided between the blower 210 and the sensor unit 310 (pressure sensor) to reduce control oscillations caused by direct feedback of high-frequency pressure fluctuations. Through digital signal processing techniques (e.g., filtering and sample averaging), the control system can process the chamber pressure signal more smoothly, thereby achieving stable pressure control. Furthermore, the system 100 may also include a temperature control element to adjust the airflow temperature at the blower outlet to match the ambient temperature, preventing adverse effects on airflow sensing accuracy due to condensation or liquid accumulation. In a Venturi-type design, a structure with an adjustable nozzle mechanism 224 may also be provided to fine-tune the differential pressure characteristics according to different clinical environments or ventilator types, thereby achieving a more personalized and customizable system configuration. This invention is not limited thereto.

[0064] In some embodiments, the pressure feedback path of system 100 may include multiple sensing and control units 602. The sensor unit 310 includes a high-pressure sensor, a temperature sensor, a pressure sensor, etc., as well as a differential pressure sensor 314 installed at both ends of the pressure-limiting orifice plate 221, and a control module 320 for comprehensive control. The control module 320 can calculate the deviation between the actual negative pressure value and the target negative pressure value by collecting various signals output by the sensing units, and further output a correction amount to the fan PWM control terminal or the Venturi nozzle opening adjustment mechanism accordingly. In certain automatic operation modes, the control module 320 can also receive respiratory phase signals sent by the ventilator or detected by sensors to identify different phases of the patient's breathing and dynamically adjust the suction intensity, automatically increasing the negative pressure during exhalation and decreasing the suction intensity during low-flow phases or inspiration, thereby achieving energy saving while reducing the risk of backflow. This control logic can be implemented through software, hardware, or firmware, and the specific strategy can be selected according to actual application requirements.

[0065] In some embodiments, both active and passive suction systems can be equipped with a pressure-limiting channel and alarm circuit 232 for system protection. When the pressure value detected in the filter buffer chamber 214 is continuously lower than a predetermined threshold, the system can automatically open the pressure relief valve to balance the pressure and activate the audible and visual alarm system, thereby alerting the operator to the abnormal situation. For implementations using active suction, a safety backoff procedure can be automatically executed through a firmware mechanism, causing the fan speed to gradually decrease and maintain at the minimum safe operating state until a manual reset signal is received. In the case of using a Venturi ejector structure, the pressure can be naturally restored to normal pressure through its bypass venting pipe, avoiding adverse phenomena such as reverse airflow, sudden noise increase, or structural stress concentration. The safety mechanism design of this invention can be flexibly configured according to the complexity of the system.

[0066] In some embodiments, by means of Figure 4A and Figure 4B The comparison of the structures shown allows for a direct observation of the differences in pressure field distribution and airflow direction between the active and passive suction mechanisms in some embodiments. Active fan systems typically achieve faster cavity pressure response and finer matching of the exhalation waveform, while passive Venturi ejector structures can still ensure basic air circulation and safe exhaust functions even during system power outages, equipment maintenance, or when entering a safety degradation mode. Depending on different usage scenarios, equipment levels, and operational requirements, this invention can flexibly select a single solution or combine the two suction principles to achieve an optimized balance between performance, cost, and reliability. This invention does not impose any limitations on this.

[0067] In conclusion, Figure 4A and Figure 4B The illustrated embodiments provide typical implementation examples of negative pressure pipelines and suction mechanisms. In some embodiments, through the integrated design of active and passive solutions, the system of the present invention can maintain a stable preset negative pressure environment under various operating conditions to achieve effective aerosol suppression and safe control. Depending on actual application or development needs, the most suitable suction solution or combination thereof can be selected based on factors such as the compatibility of the medical institution's emission system, noise control requirements, and maintenance strategies. All the above-described solutions and variations fall within the protection scope of the present invention and can be adjusted and optimized by those skilled in the art according to different conditions.

[0068] See Figure 5 In some embodiments, the sensing and sampling arrangement system of the present invention can be configured as a device for detecting and controlling the structural composition and wiring connections of key operating parameters of the negative pressure chamber 120 and the multi-stage purification assembly 140 in the system. Figure 5The diagram shows a cross-sectional view and a partially enlarged schematic of the system, illustrating the relative arrangement of sensor unit 310 (cavity pressure sensor), pre-filter differential pressure sampling port (pre-filter sampling point 311), and post-filter differential pressure sampling port (post-filter sampling point 312). Optionally, it also describes the setting scheme for temperature and humidity sensing points. In different embodiments, these sensing points can be flexibly configured in different parts of the system to achieve real-time monitoring and feedback of multiple physical parameters, thereby providing necessary data support for the control unit 602 to execute closed-loop control algorithms or other adjustment logic. This arrangement of the present invention can be adjusted according to application requirements and is not limited to... Figure 5 The configuration shown.

[0069] In some embodiments, such as Figure 5 As shown, the cavity pressure sensor (sensor unit 310) can preferably be disposed on the wall, cover, or optional independent pressure tapping interface of the negative pressure cavity 120. The cavity pressure sensor can be connected to the core area of ​​the cavity via a short conduit to achieve a stable response to the average negative pressure state within the cavity. The cavity pressure sensor can employ any type of high-precision pressure sensing element, such as a differential pressure sensing unit or a micro-pressure sensing component, which can be configured with appropriate range and resolution characteristics according to the detection requirements. For example, in some embodiments, the cavity pressure sensor may include a modular structure with temperature compensation and micro-signal amplification circuitry to improve the sensitivity and reliability of the measurement. The housing can adopt a sealed structure to prevent the intrusion of condensate and particulate matter, while the electrical connection can be connected to the signal input terminal of the control unit 602 via shielded wires, thereby achieving stable data transmission and anti-interference performance. This design of the present invention is not limited to any particular form and can be appropriately modified according to the specific system structure.

[0070] The pre-filter sampling point 311 and the post-filter sampling point 312 can be respectively located upstream and downstream of the multi-stage purification component 140, and the pressure difference between them can be used to reflect the dynamic change in filter element resistance. In some embodiments, the pre-filter sampling point 311 and the post-filter sampling point 312 can be arranged in a symmetrical spatial layout near the main airflow axis to minimize the impact of uneven airflow distribution on detection accuracy. They can be connected to the differential pressure sensor 314 via a flexible micro-conduit 317, forming a continuous and stable differential pressure acquisition path. This differential pressure signal, after being processed by the analog-to-digital conversion module, can be input to the control unit 602 and used for filter element clogging status judgment, lifespan prediction, and timely alarm prompts. This arrangement ensures that the system maintains high measurement reliability and fast response characteristics under different airflow speeds or environmental pressure changes. The application of this invention is not limited to this example.

[0071] In some optional embodiments, the sensing and sampling arrangement system can be further configured with temperature and humidity sampling points 316 for monitoring the thermal and humidity state of the airflow inside the cavity or in the exhaust channel. Temperature detection devices may include, but are not limited to, NTC-type thermistors, digital temperature sensing chips, or other suitable sensing elements; humidity monitoring can be achieved through capacitive or impedance-type humidity sensing elements. The signals output by these sensing components can be provided to the control unit 602 to identify filter condensation trends, or, in some optional cases, to adjust the operating state of the heating element to prevent condensate buildup and microbial growth, thereby significantly improving the stability and reliability of the system under long-term continuous operation. The number and location of these sensors can also be flexibly adjusted according to specific design requirements.

[0072] Figure 5 The arrangement of sampling conduits and signal lines is further illustrated. In one illustrative embodiment, each sampling channel can be a flexible tube with a suitable inner diameter, such as a miniature channel with low airflow resistance and response delay, to ensure rapid transmission of fluid pressure signals without significantly affecting the stability of the main airflow. Signal lines and power lines can be fixed to the outer wall of the housing via a unified wiring harness and routed along guide grooves to reduce mutual interference or electromagnetic coupling. In some preferred embodiments, signal lines can be shielded and have independent grounding terminals configured for the interface of control unit 602 to improve the electromagnetic compatibility and signal stability of the entire system. Of course, the present invention is not limited to the specific wire diameter or material configuration described above.

[0073] In some embodiments, the control unit 602 can acquire signals from the aforementioned various types of sensors via a multi-channel analog-to-digital converter interface. The chamber pressure signal can be primarily used to control the speed adjustment of the suction unit to maintain the required negative pressure level; the differential pressure signal can be used to monitor filter resistance, clogging status, and lifespan; and the temperature and humidity signals can be used to drive the anti-condensation heating logic or adjust the operating environment. The control algorithm employed in the control unit 602 can be based on weighted fusion, fuzzy logic, or any other applicable algorithm to achieve comprehensive evaluation and dynamic adjustment of multiple parameters. Through this control strategy based on multi-signal collaborative optimization, the system can maintain a stable and reliable operating state under different breathing flow, humidity, and temperature conditions, while enhancing response accuracy and safety.

[0074] In another alternative embodiment, the cavity pressure sensor and differential pressure sensor 314 can be designed as an integrated sensing module structure to reduce the number of external interfaces and lower piping complexity. This module can integrate temperature compensation circuitry and digital communication interfaces, such as I²C, SPI, or other equivalent digital buses, to ensure high-precision signal acquisition and excellent anti-interference performance. In some embodiments, this integrated module can be installed outside the maintenance area of ​​the housing 102 and connected to each sampling point via short leads, allowing maintenance personnel to easily perform sensor calibration or unit replacement operations, thereby enhancing the system's ease of maintenance, reliability, and reusability under long-term operating conditions. The present invention does not limit the implementation form of this module.

[0075] To ensure the safety and traceability of power supply and signal transmission, in some preferred embodiments, Figure 5 The signal lines shown can be managed using color differentiation, label coding, or numerical identification. The control system can monitor the working status of each sensor path in real time through software or hardware modules. When conditions such as air blockage, signal loss, abnormal voltage, or communication errors are detected, it can automatically record alarm events and output maintenance prompt signals. This type of status monitoring and protection function can effectively improve the overall safety and reliability of the system, thereby avoiding a decrease or lag in the accuracy of closed-loop control due to sampling anomalies. The implementation of this invention can be further adjusted according to the application scenario and is not limited to the illustrated example.

[0076] In conclusion, Figure 5 The sensing and sampling system shown achieves comprehensive dynamic monitoring of the system's internal operating conditions through a collaborative mechanism of multi-point pressure tapping and multi-parameter detection. This arrangement not only provides accurate real-time feedback on filter performance degradation and cavity pressure fluctuations, but also supports the control unit 602 in performing various functions, including but not limited to active adjustment, status assessment, self-diagnosis, and safety protection. Regardless of environmental pressure, humidity, or temperature conditions, this arrangement ensures system operational stability, response speed, and reliability, thereby further meeting the overall technical requirements of this invention regarding control accuracy and safety monitoring. The implementation of this invention can be flexibly adjusted according to actual usage needs and is not limited to the above exemplary embodiments.

[0077] See Figure 6AIn some embodiments, the control and timing system 600 of the present invention can be configured to implement closed-loop control and phase synchronization logic for the negative pressure chamber. The control and timing system 600 may include at least one control unit 602, a pressure sampling module 604, a respiratory phase signal input module 606, a PID controller 608, a limiting protection module 610, and an abnormal backoff and interlocking module 612, among other functional units. Each unit can be implemented independently or integrated. Optionally, the modules can communicate signal flow and logical relationships through signal lines, bus communication, or wireless data links. Figure 6B This is a time-history overlay diagram of an aerosol suppression module used in the expiratory phase of a ventilator. The overlay diagram depicts the changes in intracavitary pressure during the initial and final stages of expiration, along with the corresponding waveform characteristics of the suction power or output control signal, thus reflecting the dynamic response behavior of the control system at different respiratory phases. This invention is not limited to the above structure; other implementations can also be used to achieve the same control effect.

[0078] In some preferred embodiments, the control unit 602 can be implemented using a microcontroller, embedded processing chip, or programmable logic unit, internally running a multi-task control or parallel task management program to process signal input from the pressure sampling module 604. The pressure sampling module 604 can collect real-time pressure data within the negative pressure chamber 120 and pressure difference information before and after filtering, and can feed back the filtered and analog-to-digital converted data to the PID controller 608. The PID controller 608 can calculate the error signal based on the target chamber pressure range and generate a control signal through three adjustment parameters: proportional, integral, and derivative, thereby driving the output power of the suction unit (e.g., blower, ejector valve, or other pneumatic device) to achieve stable control of the chamber pressure. For example, in some non-limiting embodiments, the target chamber pressure can be within a preset negative pressure range to maintain a stable expiratory pathway. This invention is not limited to using a PID control algorithm; similar closed-loop stabilization effects can also be achieved through fuzzy control, adaptive control, or model-based predictive control.

[0079] In some embodiments, the respiratory phase signal input module 606 can receive signals related to valve opening / closing status or airflow direction from the ventilator main control system to identify the inspiratory and expiratory phases. Optionally, the control logic can be configured to activate the preset negative pressure control loop only during the expiratory phase and enter standby mode during the inspiratory phase to avoid the generation of reverse pressure differential. The timing diagram can display the corresponding response relationship. When the expiratory valve opening is detected, the target chamber pressure can gradually transition from normostatic pressure to the set negative pressure level, and the suction control signal rises synchronously. When the end-expiratory signal is detected, the output control signal gradually weakens, and the chamber pressure returns to near-normative pressure. In other embodiments, the system delay can be compensated by adjusting the lead or hysteresis, thereby obtaining a smoother pressure response.

[0080] To further prevent instability such as overshoot or differential pressure oscillation, the limiting protection module 610 can be configured to monitor the cavity pressure signal and set a predetermined negative pressure upper limit threshold. When the cavity pressure exceeds this limit, the system can automatically reduce or cut off the suction output, thereby protecting the equipment and related components. Optionally, a time-integration protection logic can also be set, that is, when the negative pressure continues for more than a preset time without recovery, the controller can activate a safe operation mode, in which low-speed drive is maintained to keep the expiratory pathway open. Through such protection mechanisms, the stability of the system can be effectively improved, avoiding the impact of improper over-suction on the patient's exhalation, while reducing the risk of overload and pressure on the cavity structure. This invention is not limited to a specific threshold setting method; the limiting parameters can be flexibly adjusted according to the application scenario or cavity characteristics.

[0081] In some embodiments, the abnormal backoff and interlocking module 612 can be used to handle various abnormal events that occur during the operation of the control system, such as sensor signal loss, power fluctuations, fan jamming, or detection of chamber pressure exceeding safety limits for an extended period. When any abnormal condition is triggered, the control and timing system 600 can automatically enter backoff mode, disconnect the closed-loop regulation output and switch to the passive exhaust channel, while simultaneously issuing an audible and visual alarm. Optionally, the interlocking module can also communicate with an external sensing unit, and when a filter element is detected to be removed or the housing is opened, it can shut down the UV-C light source and the suction motor via communication commands to ensure operational safety and equipment protection. The time-history overlay diagram can be represented by the rapid decline of the output signal and the rise of the alarm indicator signal. This logic can be implemented through software instructions, hardware circuits, or a combination of both.

[0082] In some embodiments, the control and timing system 600 may further include a phase correction module 613 for adaptive compensation and calibration based on the phase difference between the cavity pressure feedback response delay characteristics and the ventilator master control signal. The phase correction module 613 can automatically determine the advance or lag angle of the control signal output by calculating the data change trend over multiple consecutive respiratory cycles, so as to quickly establish the required target preset negative pressure at the beginning of expiration. In this way, it can be ensured that aerosols are effectively controlled immediately at the start of expiratory flow. For example, a time-history overlay plot can characterize the adjustment result, showing that the cavity pressure curve rapidly decreases to the target range at the beginning of each cycle and smoothly rises again at the end of expiration. This phase correction module can be implemented through software algorithms, hardware delay compensation, or a combination of both, and the specific form can be flexibly configured according to system requirements.

[0083] In some embodiments, the control unit 602 can be configured to implement a dual-closed-loop superimposed adjustment structure, wherein the inner loop uses the cavity pressure signal as the primary feedback signal to achieve rapid response, while the outer loop uses the respiratory phase signal and filter resistance status as references for relatively slow adjustment. This nested control structure can maintain a stable system response to rapid fluctuations in expiratory flow rate, while also possessing adaptive adjustment capabilities to long-term changes in filter resistance or performance degradation. The timing diagram can show the tracking consistency between the expiratory flow rate waveform (solid line) and the cavity pressure reference waveform (dashed line), demonstrating that the control system can maintain a high degree of dynamic matching and steady-state accuracy throughout the complete respiratory cycle. This invention does not limit the specific control algorithm; fuzzy logic adjustment, adaptive learning, or variable gain control methods can also be used to achieve equivalent functions.

[0084] In terms of security strategy design, Figure 6A The exception rollback logic shown can be integrated with other modules in the system (e.g., Figure 5 The sensing and sampling system maintains continuous communication or data sharing. Optionally, when problems such as sensor disconnection, signal drift, or abnormal noise are detected, the control unit can generate redundant alternative values ​​to temporarily maintain closed-loop control, and, if necessary, cut off the suction drive and activate audible and visual alarms according to preset safety logic until the abnormal situation is resolved. This safety mechanism enables the system to maintain a controllable and safe operating state even under unexpected conditions, thereby further improving the overall system reliability and safety in medical and life support applications.

[0085] In conclusion, Figure 6AThe control and timing system 600 shown achieves precise pressure field adjustment and respiratory phase synchronization control of the negative pressure chamber at the expiratory end of the ventilator through the synergistic action of multiple functional modules and a dual closed-loop control architecture. This solution significantly reduces chamber pressure fluctuations, thereby improving the stability and efficiency of the aerosol capture process. Simultaneously, the control and timing system 600 also features automatic fallback and interlocking safety mechanisms, which can quickly enter protection mode upon detecting abnormal conditions to ensure stable system operation and safe use. This embodiment of the invention effectively supports the implementation of control principles and safety logic, and maintains reliable performance under both continuous operation and sudden abnormal conditions. The invention is not limited to this embodiment and can be optimized and adjusted according to different medical scenarios or system configurations.

[0086] See Figure 7 In some embodiments, the condensation and drainage management system can be constructed as a cross-sectional structure extending longitudinally along the main airflow channel, illustrating an overall configuration for achieving airflow thermal control and liquid drainage path arrangement. Optionally, the system may have zoned heating elements 510 and insulation layers 511 in the negative pressure chamber area. The zoned heating elements 510 can be used to form a preset gradient in the temperature distribution of the chamber wall through precise temperature control, thereby predicting and guiding the location of condensate formation, effectively reducing or avoiding the formation of condensate accumulation in the chamber wall and filter element area. In some specific embodiments, the chamber wall material may include, but is not limited to, metal foil, thermally conductive composite materials, or a multi-layer composite structure with resistance heating wire layers. Each heating zone 529 segment can be continuously monitored by a temperature sensor 525 and maintained within a target temperature range through an electronic feedback loop. This temperature range can be set to a temperature difference range slightly higher than the airflow dew point, for example, a few degrees Celsius higher than the dew point, so that the condensation point is gradually guided to the drainage area. The above structure can be tailored or extended according to the system scale and application scenario, and the present invention does not limit this.

[0087] In this embodiment, the zoned heating element 510 can be disposed on the wall of the housing 102, and its heating output can be graded and adjusted according to the heat load characteristics of different sections to achieve more precise temperature distribution control. For example, optionally, the upper heating zone 529 can maintain a relatively low temperature to avoid excessive drying of the gas or thermal damage to the filter material, while the bottom heating zone 529 can provide higher heat power to reduce the probability of condensate formation. Preferably, the insulation layer 511 can be made of porous silicone pads, high-reflectivity films, or other materials with heat shielding properties to reduce heat loss from the cavity and achieve a smooth transition of the internal temperature gradient. Through the above-mentioned layered and zoned structural design, the formation of condensate can be transferred from the wall to the bottom drainage channel or collection tank 520, thereby achieving automatic guidance and discharge of liquid while maintaining smooth airflow. The present invention is not limited to specific materials and arrangements.

[0088] See Figure 7 In some embodiments, the bottom collection tank 520 can be located at the lowest point of gravity inside the housing to collect liquid generated by condensation. The collection tank 520 can be designed as an arc-shaped groove structure or a detachable collection cup structure, and the specific form can be freely selected according to the equipment size and maintenance convenience. Its volume can be determined comprehensively based on the expected amount of condensate generated and the system operating cycle, and can vary in the range of several milliliters to tens of milliliters. The specific value can be determined by those skilled in the art as needed. To prevent liquid backflow or leakage, a one-way drain valve 521 can be optionally connected to the bottom of the tank. The valve is connected to the outside and can be set to open at a specific pressure threshold. For example, when the pressure difference between the cavity and the external environment exceeds a set trigger value, the internal liquid can be discharged one-way. The discharged liquid path can extend to a chemical treatment chamber 522 with chemical treatment function for neutralizing or sterilizing the discharged liquid, and then guided to a safe and sealed collection bottle 528 through a drain pipe 524, thereby improving the safety and controllability of the system.

[0089] In some preferred embodiments, the chemical treatment chamber 522 may include at least one adsorbent layer or chemical oxidant layer, such as a peroxide-based slow-release medium treatment structure, for inactivating or neutralizing the discharged liquid and any aerosol residues mixed in it. The chamber body of the chemical treatment chamber 522 itself may be made of corrosion-resistant plastic, medical-grade stainless steel, or other chemically resistant materials, and the inner wall may optionally be coated with an antibacterial coating to prevent microbial adhesion and reproduction. The treated liquid can flow along the drainage path into an external sealed collection bottle, so that the discharged condensate will not cause secondary pollution containing pathogenic substances. In some embodiments of the present invention, the entire drainage path is relatively independent from the main chamber, but reliably connected through a sealed interface to ensure that the system maintains a stable preset negative pressure state and continuous gas path integrity.

[0090] In some embodiments, to further enhance the operational stability of the condensation and drainage management system, a gas-liquid separation structure 523 may be provided in the drainage path. The function of the gas-liquid separation structure 523 is to prevent airflow from entering the collection tank 520 in reverse or causing liquid oscillation. This gas-liquid separation structure 523 can employ a hydrophobic membrane assembly, a cyclone separator, or other forms of separation mechanism. Its design features allow for low airflow resistance while providing high liquid blocking capability. Even under conditions of dynamic fluctuations in cavity negative pressure, the gas-liquid separation structure 523 can maintain the stability of the drainage flow, thereby achieving long-term continuous operation without blockage. Through the comprehensive design of the above-mentioned gas-liquid separation, thermal control, and drainage layout, the airflow channel can be further ensured to remain unobstructed in high-humidity environments, avoiding problems such as abnormal local pressure drop, increased filtration resistance, or sensor contamination caused by liquid accumulation. This invention is not limited to specific structural forms and materials.

[0091] In another embodiment, the system can establish a closed-loop control mechanism by integrating temperature and humidity sensing components to achieve automated condensation management. This control mechanism may include a control algorithm that adjusts the output power of the zoned heating elements 510 in real time based on the cavity temperature gradient, predicted wall dew point, and the signal from the liquid level sensor 526. In actual operation, when an increased condensation trend is detected, the system control unit 602 can automatically increase the temperature of the bottom heating group or open the one-way drain valve 521 for a short period to discharge accumulated liquid. This dynamic adjustment mode allows the system to maintain constant airflow humidity while avoiding energy waste caused by overheating, thereby extending the service life of the filter elements and further ensuring the aerodynamic stability and operating efficiency of the cavity. The control logic of this invention can be implemented through hardware, software, or firmware, and can also be modified according to different device platforms.

[0092] Regarding the anti-clogging design, in some embodiments, the inlet of the collection tank 520 may be equipped with a splash guard 527 or a grid structure with filtering function to prevent droplets from splashing onto the filter element area and causing contamination due to turbulence or airflow impact. The drain line can be arranged in a sloped configuration or made of transparent material, depending on the system layout, to enable visual monitoring of the liquid flow. To further reduce the risk of clogging of the one-way drain valve 521 due to biofilm formation or particle deposition, the valve body may employ a replaceable sealing diaphragm or a design structure with anti-clogging micropores, and can remove accumulated liquid through an automatic oscillation mechanism when necessary. Overall system maintenance can be performed through the external inspection port without disassembling the cavity structure, thus ensuring continuous sealing and operational safety and reliability. This invention does not limit the configuration of such structures.

[0093] In summary, as Figure 7 The condensation and drainage management scheme shown achieves controllable guidance and safe discharge management of condensate through the coordinated configuration of multiple modules, including a zoned heating device, insulation structure, liquid collection element, and one-way drainage valve. In some embodiments, this scheme can effectively reduce the risks of channel blockage, secondary splashing, and pathogen spread caused by condensate accumulation during long-term continuous operation, while maintaining the reliability of the overall aerodynamic performance of the system while keeping the preset negative pressure environment of the cavity stable. The above structure and its principle can be used as an independent system or combined with the aforementioned purification module and control unit to form a comprehensive exhalation end management system to achieve condensation control and safe drainage functions. This invention provides... Figure 7 The specific embodiments described are not intended to be limiting, and any equivalent substitutions, functional extensions or structural modifications should be considered to be included within the scope of protection of this invention.

[0094] refer to Figure 8As shown, the multi-stage purification component 140 can be detachably installed in the negative pressure cavity 120 formed by the housing 102. The safety interlock mechanism 721 is associated with the housing 102. The housing includes a cover, which is closedly installed at the opening of the housing. The cover is provided with a buckle 713, and the opening is provided with an elastic locking component 714. The buckle 713 and the elastic locking component 714 engage with each other.

[0095] The multi-stage purification assembly 140 may include a quick-replaceable integrated filter structure 140a, which may include a pre-filtration unit 141, a final filtration unit (HEPA filter) 142, and an electrostatic capture unit 143. The integrated filter structure 140a can be quickly replaced via a detachable mechanism. When inserted into the housing 102, the integrated filter structure 140a engages with the filter cartridge guide rail 712 of the housing 102. The safety interlock mechanism 721 includes a sensing unit and an interlock circuit mounted on the housing 102 for detecting the installation status of the integrated filter structure 140a. The interlock circuit connects the sensing unit and the control unit 602, and is used to prevent the negative pressure forming mechanism from starting when the integrated filter structure 140a is not locked. Optionally, an open-cover interlock control and identification mechanism can be combined to ensure that the irradiation source and suction system are in a safe off state during maintenance or replacement of the integrated filter structure 140a, thereby effectively preventing operational risks.

[0096] In some embodiments, the safety interlock mechanism 721 includes an over-negative pressure protection channel connecting the negative pressure chamber 120 to the external environment and an electrical alarm module. The over-negative pressure protection channel is provided with a pressure limiting valve. The pressure limiting valve is configured to automatically open to balance the pressure when the pressure in the negative pressure chamber 120 is lower than a predetermined limit. The electrical alarm module is signal-connected to the pressure sensing unit and is configured to output alarm information when the pressure sensing unit detects an abnormal pressure.

[0097] Optionally, an RFID tag 720 can be installed on the outer frame of the integrated filter structure 140a to store information including filter model, production batch, and cumulative operating time. The control unit can read the tag via a near-field communication device when the system is powered on, and control the system's operating status based on the identification results. For example, when a mismatched filter model or a filter exceeding its set lifespan is detected, the system can automatically lock the UV-C light source and suction motor via software logic, thereby preventing the continued use of substandard or expired filters and improving overall safety. This RFID identification mechanism can also be used for material traceability management in hospitals or laboratories, facilitating the implementation of maintenance logs. In some embodiments, when the system housing 102 is detected to be opened, the interlock switch triggers the system to execute a pre-set safety action sequence. For example, the system can first immediately interrupt the power supply path of the UV-C light source to prevent ultraviolet radiation leakage; then, through control logic, delay shutting down the fan for several seconds to ensure sufficient attenuation of residual ozone and ultraviolet reflected light within the cavity; finally, releasing the pressure in the suction circuit to restore the airflow to normal pressure. The aforementioned safety logic can be implemented through electronic control modules, mechanical power-off devices, or a combination thereof, thus providing flexible configuration options to meet different cost and safety level requirements. This design can significantly reduce operational risks during maintenance or repair, ensuring that operators are protected from the hazards of ultraviolet radiation or negative pressure environments.

[0098] In some embodiments, a detection mechanism for detecting the installation status of the integrated filter structure 140a is also included, such as a limit switch, Hall switch, or photoelectric sensor, for detecting whether the integrated filter structure 140a is in place and locked; when it is detected that it is not locked or not in place, the control unit prohibits the suction unit from starting or stops immediately and gives an alarm prompt.

[0099] After the above interlocking action is completed, the negative pressure chamber is no longer actively driven by the suction unit. The airflow in the chamber is passively discharged to the external environment through the shell by the pressure difference of the ventilator's expiratory valve.

[0100] In another embodiment, Figure 9 The illustrated structure also includes control logic for the delayed shutdown of the UV-C light source. The light source module 706 may include a timing control circuit to initiate a delay program upon detecting an open cover signal, causing the UV-C light source to gradually reduce its power and eventually shut down within a set period. This method avoids arcing due to momentary power outages or shortened lifespan caused by frequent start-stop cycles. For example, this delay control logic can cooperate with a temperature monitoring circuit to stop operation once the light source temperature drops to a safe value, thereby further ensuring the long-term stability of the equipment. This invention does not limit the specific timing scheme or circuit form; this logic can also be implemented through software delay control or other programmable logic components.

[0101] like Figure 8 and Figure 9 As shown, in some embodiments, the safety interlock system may include a filter element differential pressure alarm device 731, which determines whether a blockage exists by real-time detection of the airflow differential pressure before and after the filter element. The control unit can generate an alarm signal when the detected differential pressure reaches a predetermined threshold to remind the operator to perform filter element replacement or maintenance. As an illustrative example, when the differential pressure increases to a certain value, the system will simultaneously issue an audible and visual alarm and display a prompt message on the control interface, such as "Filter element needs replacement" or similar content. Furthermore, the above alarm logic can interact with an RFID identification mechanism to achieve automatic updating and tracking of the filter element status, thereby preventing the reuse of expired or blocked filter elements and ensuring smooth airflow and purification effect. Specific thresholds can be adjusted and set by technicians according to the system application scenario, and this invention does not limit this.

[0102] In some embodiments, the safety interlock mechanism further includes an over-negative pressure protection channel connecting the negative pressure chamber to the external environment, within which a safety valve 231 is installed. This safety valve 231 can be configured to automatically open when the chamber pressure falls below a set lower limit, allowing outside air to enter the chamber to alleviate the internal negative pressure and restore it to a safe pressure level. For example, the safety valve 231 can be a spring-loaded diaphragm structure or manufactured using a one-piece molded silicone valve plate, with a response time as low as an extremely short time order to ensure rapid pressure balancing under various abnormal operating conditions. Optionally, the valve body can be provided with a transparent window to facilitate periodic inspection of the valve plate and seals by technicians. The safety valve design of this invention is highly versatile, allowing for the selection of appropriate structures and material configurations according to different system pressure levels.

[0103] In some particular embodiments, Figure 9 The execution sequence of the safety interaction logic is illustrated in flowchart form. In a typical scenario, this process includes multiple safety steps executed sequentially, such as: Step A, detecting the opening signal; Step B, shutting off the UV-C light source; Step C, delaying and stopping the fan operation; Step D, releasing the negative pressure in the cavity; and Step E, issuing an alarm. This process forms a top-down, multi-layered protection logic, effectively preventing UV irradiation damage or contaminant leakage due to misoperation during maintenance. After maintenance is completed and normal assembly is restored, the system can reread the RFID identification information and execute a self-test program to confirm that all components are correctly installed and operating parameters have returned to normal before allowing the system to restart. The safety logic framework of this invention can be implemented through hardware or software, and is not limited to the embodiments described.

[0104] Overall, Figure 8The illustrated structural examples comprehensively demonstrate the collaborative working characteristics of the maintenance and safety system of this invention. Through the combined action of multiple functional modules, including the quick-change snap-fit ​​structure, RFID tag 706 and identification module, delay control circuit, differential pressure monitoring alarm, and over-negative pressure protection device, in some embodiments, rapid and safe filter replacement and reliable equipment maintenance can be achieved while maintaining system sealing and purification efficiency. Furthermore, the logical interconnection of the above modules forms a human-machine safe interactive linkage control system, thereby meeting multi-level safety control requirements and operational convenience standards. The solution provided by this invention has high versatility and expansion potential, and can be applied to air purification or disinfection systems of different scales or application scenarios.

[0105] Furthermore, in the description of this disclosure, "multiple" means two or more, unless otherwise expressly and specifically limited.

[0106] The above are merely specific embodiments of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. An aerosol suppression module for the expiratory end of a ventilator, characterized in that, include: The housing has an inlet and an outlet, the inlet being used for an airtight connection with the outlet of the ventilator's exhalation valve, and a negative pressure chamber is formed inside the housing extending from the inlet to the outlet; A rectifier structure is disposed in the negative pressure cavity adjacent to the inlet, and is used to rectify the airflow entering from the inlet to form laminar flow; A multi-stage purification component is sealed and disposed downstream of the rectifier structure to divide the negative pressure chamber into an upstream region and a downstream region. The multi-stage purification component includes at least one stage particle filtration unit and a diffusion silencing unit arranged sequentially along the airflow direction. A negative pressure forming mechanism is connected to the outlet of the housing and is used to draw gas from the negative pressure cavity to establish and maintain a preset negative pressure in the negative pressure cavity; The pressure sensing unit is in fluid communication with the negative pressure cavity and is used to collect the pressure signal in the negative pressure cavity in real time. The control unit is connected to the pressure sensing unit and electrically connected to the negative pressure forming mechanism, and is used to adjust the suction intensity of the negative pressure forming mechanism based on the pressure signal. A safety interlock mechanism, associated with the housing, is used to stop the suction of the negative pressure forming mechanism and allow passive airflow discharge when the housing cover is detected to be open or a system malfunction signal is detected.

2. The aerosol suppression module for the expiratory end of a ventilator according to claim 1, characterized in that, The negative pressure forming mechanism includes a miniature blower or a turbine suction unit disposed at the outlet of the housing. The control unit is electrically connected to the miniature blower or the turbine suction unit and is used to control the miniature blower or the turbine suction unit to maintain the preset negative pressure.

3. The aerosol suppression module for the expiratory end of a ventilator according to claim 1, characterized in that, The negative pressure forming mechanism includes a Venturi ejector assembly, the air intake of which is in fluid communication with the negative pressure cavity. The Venturi ejector assembly is configured to generate the preset negative pressure in the negative pressure cavity by relying on the kinetic energy of the main airflow flowing through it. A pressure limiting orifice plate and an overflow bypass are provided on the air intake pipe of the Venturi ejector assembly.

4. The aerosol suppression module for the expiratory end of a ventilator according to claim 1, characterized in that, The control unit is configured to receive the respiratory phase signal sent by the ventilator or the respiratory phase signal detected by the matching phase sensor, and establish a dual closed-loop control logic based on the pressure signal in the negative pressure chamber and the respiratory phase signal, so as to dynamically adjust the output of the negative pressure forming mechanism when the expiratory phase is detected, so as to make the expiratory resistance controllable and maintain the airflow stable.

5. The aerosol suppression module for the expiratory end of a ventilator according to claim 1, characterized in that, The multi-stage purification component also includes an ultraviolet sterilization unit, which is located downstream of the particulate filtration unit or integrated into the particulate filtration unit. The ultraviolet sterilization unit includes an ultraviolet light source facing the airflow channel and a sterilization cavity with a highly reflective inner wall surrounding the airflow channel, used to sterilize and inactivate the passing airflow.

6. The aerosol suppression module for the expiratory end of a ventilator according to claim 1, characterized in that, The shell wall is provided with a heating element, which is used to maintain the shell surface temperature above the dew point to reduce condensation. The bottom of the shell is provided with a liquid collection tank, which is equipped with a one-way drain valve to achieve directional discharge when the condensate reaches a preset level.

7. The aerosol suppression module for the expiratory end of a ventilator according to claim 1, characterized in that, The multi-stage purification component includes a quick-replaceable integrated filter element structure. The safety interlock mechanism includes a sensing unit and an interlock circuit disposed on the housing for detecting the installation status of the filter element structure. The interlock circuit connects the sensing unit and the control unit and is used to prevent the negative pressure forming mechanism from starting when the filter element structure is not locked.

8. The aerosol suppression module for the expiratory end of a ventilator according to claim 1, characterized in that, The safety interlock mechanism includes an over-negative pressure protection channel connecting the negative pressure chamber to the external environment and an electrical alarm module. The over-negative pressure protection channel is equipped with a pressure limiting valve. The pressure limiting valve is configured to automatically open to balance the pressure when the pressure in the negative pressure chamber is lower than a predetermined limit. The electrical alarm module is signal-connected to the pressure sensing unit and is configured to output alarm information when the pressure sensing unit detects an abnormal pressure.

9. The aerosol suppression module for the expiratory end of a ventilator according to claim 1, characterized in that, The inlet of the housing is connected to the ventilator tubing via a standard interface, and an airflow diffusion grille is provided inside the housing on the outlet side of the multi-stage purification component to reduce airflow resistance and dead space volume, thereby ensuring compatibility with different models of ventilators and maintaining low-noise operation.

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