Airway structure and breathing machine

Abstract

This application relates to a gas path structure and a ventilator. The gas path structure is used for gas delivery in the ventilator and includes a gas source, a pressure reducing valve, and a detection branch. The pressure reducing valve includes an input end and an output end. The input end is connected to the gas source, and the output end is used to connect to the user. The detection branch is connected to the output end of the pressure reducing valve and is used to detect the pressure at the output end. Because the detection branch is connected to the output end of the pressure reducing valve, it can detect the pressure at the output end in real time, providing a reference for adjusting the pressure of the pressure reducing valve. Compared to traditional technologies that require disassembling the pressure reducing valve for separate pressure adjustment, the gas path structure provided in this application, by setting a detection branch that can detect the pressure at the output end of the pressure reducing valve, allows for pressure adjustment of the pressure reducing valve without disassembling it. This improves the convenience of pressure adjustment during factory testing, fault diagnosis, troubleshooting, and maintenance. A ventilator including the above-mentioned gas path structure makes pressure adjustment of the pressure reducing valve more convenient.

Description

Technical Field

[0001] This application relates to the field of ventilator technology, and in particular to an airway structure and a ventilator. Background Technology

[0002] A ventilator is a medical device that can partially or completely replace spontaneous ventilation. Traditional ventilators consist of a gas tank and a pressure reducing valve. The gas tank provides high-pressure gas for ventilation, and the pressure reducing valve, connected to the outlet of the gas tank, reduces the high-pressure gas to the desired pressure. Different gas tanks provide different gas pressures, so the pressure reducing valve usually needs to be adjusted.

[0003] In current ventilators, when the pressure at the output of the pressure reducing valve does not meet the expected pressure, the pressure reducing valve needs to be disassembled and the pressure adjusted using a separate tool, which is a cumbersome operation. Summary of the Invention

[0004] Therefore, it is necessary to provide an airway structure and ventilator to address the problem of cumbersome pressure adjustment operation of the pressure reducing valve in the ventilator.

[0005] This application provides a gas path structure for gas delivery in a ventilator, the gas path structure comprising:

[0006] Gas source;

[0007] A pressure reducing valve, comprising an input end and an output end, wherein the input end is connected to the gas source and the output end is used to connect to the user;

[0008] A detection branch is connected to the output end of the pressure reducing valve, and the detection branch is used to detect the pressure at the output end.

[0009] In one embodiment, the detection branch includes a delivery tube, a pressure detector, and a shut-off valve. One end of the delivery tube is connected to the output end, and the other end of the delivery tube is used to connect to the outside of the ventilator. The pressure detector is located on the delivery tube to detect the pressure inside the tube, and the shut-off valve is located on the delivery tube to cut off the gas delivery of the delivery tube.

[0010] In one embodiment, the gas path structure further includes a flow control module connected to the output end to regulate the flow rate of the gas flowing through it, and the detection branch is connected between the pressure reducing valve and the flow control module.

[0011] In one embodiment, the flow control module includes a proportional valve, a flow stabilizer, and an intake flow sensor. The flow stabilizer is used to reduce the turbulence of the flowing gas. The proportional valve, the flow stabilizer, and the intake flow sensor are connected in sequence along the gas flow direction within the gas path structure.

[0012] In one embodiment, the flow stabilizer is a sintered filter.

[0013] In one embodiment, the gas path structure includes an intake path, which includes an oxygen branch, and the oxygen branch includes the gas source, the pressure reducing valve, the detection branch, and the flow control module connected in series.

[0014] In one embodiment, the intake path further includes an air branch, which also includes the air source, the pressure reducing valve, the detection branch, and the flow control module connected in series.

[0015] In one embodiment, the gas path structure further includes an exhalation path and a purge path. The exhalation path includes an exhalation flow sensor, and the purge path connects the gas source and the exhalation flow sensor. The purge path is provided with a purge switch valve for cutting off or opening the purge path.

[0016] In one embodiment, the gas path structure further includes an atomizing path, and the purging path is also connected to the atomizing path.

[0017] This application also provides a ventilator, which includes the airway structure described above.

[0018] In the aforementioned gas path structure, the detection branch is connected to the output end of the pressure reducing valve. Therefore, the detection branch can detect the output pressure in real time, providing a reference for pressure adjustment of the pressure reducing valve. Thus, after the gas path structure is assembled with other components of the ventilator, the pressure value of the gas output from the gas source under the pressure-reducing action of the pressure reducing valve can be detected through the detection branch. Furthermore, when the output pressure of the pressure reducing valve does not meet expectations, the pressure reducing valve can be adjusted based on the pressure detected by the detection branch to bring the output pressure to the expected level. In other words, compared to traditional technologies that require disassembling the pressure reducing valve for separate pressure adjustment, the gas path structure provided in this application, by setting up a detection branch capable of detecting the output pressure of the pressure reducing valve, allows for pressure adjustment of the pressure reducing valve without disassembling it. This improves the convenience of pressure adjustment during factory testing, fault diagnosis, troubleshooting, and maintenance. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the circuit of a ventilator provided in one embodiment of this application.

[0020] Figure 2 This is a schematic diagram of a detection branch provided in one embodiment of this application.

[0021] Figure reference numerals: 10, Gas path structure; 100, Intake path; 101, Oxygen branch; 102, Air branch; 103, Safety branch; 110, Gas source; 111, Oxygen source; 112, Air source; 121, Gas source pressure detector; 122, Pressure relief valve; 123, Gas source filter; 124, Check valve; 130, Pressure reducing valve; 140, Detection branch; 150, Flow control module; 151, Proportional valve; 152, Flow stabilizer; 153, Intake flow sensor; 154 161. Inspiratory resistance; 162. Mixer; 163. Inspiratory pressure sensor; 171. Oxygen concentration sensor; 172. Mechanical safety valve; 173. Electronic safety valve; 200. Expiratory path; 210. Electronic PEEP valve; 220. Expiratory valve; 230. Expiratory flow sensor; 240. Expiratory pressure sensor; 300. Purge path; 310. Selector valve; 320. Purge switch valve; 400. Nebulizer path; 410. Nebulizer switch valve; 420. Nebulizer; 20. User. Detailed Implementation

[0022] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0023] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0024] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0025] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0026] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0027] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0028] See Figure 1 , Figure 1 A schematic diagram of the circuit of a ventilator provided in one embodiment of this application is shown. The ventilator provided in one embodiment of this application (not shown in the figure, the same below) includes an airway structure 10, which is used for gas delivery of the ventilator.

[0029] In one embodiment, the gas path structure 10 includes a gas source 110, a pressure reducing valve 130, and a detection branch 140. The pressure reducing valve 130 includes an input end and an output end. The input end is connected to the gas source 110, and the output end is used to connect to the user 20. The detection branch 140 is connected to the output end of the pressure reducing valve 130, and the detection branch 140 is used to detect the pressure at the output end.

[0030] In the aforementioned gas path structure 10, the detection branch 140 is connected to the output end of the pressure reducing valve 130. Therefore, the detection branch 140 can detect the pressure at the output end in real time, providing a reference for the pressure adjustment of the pressure reducing valve 130. Thus, after the gas path structure 10 is assembled with other structures included in the ventilator, the pressure value of the gas output from the gas source 110 under the pressure reduction action of the pressure reducing valve 130 can be detected through the detection branch 140. Furthermore, when the output pressure of the pressure reducing valve 130 does not meet expectations, the pressure reducing valve 130 can be adjusted based on the pressure detected by the detection branch 140 to adjust the output pressure to the expected pressure. In other words, compared to the conventional technology that requires disassembling the pressure reducing valve 130 for separate pressure adjustment, the gas path structure 10 provided in this application, by setting a detection branch 140 capable of detecting the pressure at the output end of the pressure reducing valve 130, can adjust the pressure reducing valve 130 without disassembling it, thus improving the convenience of pressure adjustment during factory testing, fault diagnosis, troubleshooting, and maintenance.

[0031] Furthermore, the aforementioned gas path structure 10 is configured such that pressure adjustment can be performed without disassembling the pressure reducing valve 130. This allows for pressure adjustment of the pressure reducing valve 130 after the ventilator is essentially assembled, reducing the likelihood of accidental activation of the pressure reducing valve 130 during assembly and causing pre-adjustment failure. In other words, adjusting the pressure reducing valve 130 after assembly improves the effectiveness of pressure adjustment.

[0032] Furthermore, the aforementioned gas path structure 10 extends a detection branch 140 along the gas delivery path, simplifying the pressure detection method at the output of the pressure reducing valve 130 and reducing the required structure for pressure detection. For example, if a pressure detector were built into the pressure reducing valve 130 to detect the output pressure, the detector would need to be integrated into the valve, increasing both the cost and size of the valve, making assembly inconvenient. Additionally, the installation location of the pressure reducing valve 130 would restrict its operation, making pressure adjustment less convenient.

[0033] Furthermore, the detection branch 140 can extend away from the pressure reducing valve 130. For example, the ventilator also includes a housing, with the airway structure 10 disposed within the housing, and the end of the detection branch 140 away from the pressure reducing valve 130 can be embedded in the housing for operation from outside the housing. Of course, in other embodiments, the detection branch 140 can also be arranged in other easily accessible parts of the ventilator.

[0034] Please see Figure 2 In one embodiment, the detection branch 140 includes a delivery tube, a pressure detector, and a shut-off valve. One end of the delivery tube is connected to the output end, and the other end is connected to the outside of the ventilator. The pressure detector is located on the delivery tube to detect the pressure inside the tube, and the shut-off valve is located on the delivery tube to cut off the gas delivery. When it is necessary to adjust the pressure of the pressure reducing valve 130, the shut-off valve is opened to connect the delivery tube to the output end and have the same pressure, so that the pressure detector can detect the pressure at the output end. When it is not necessary to detect the pressure of the pressure reducing valve 130, the shut-off valve can be closed to cut off the delivery tube, reducing the negative impact of the delivery tube on ventilator ventilation.

[0035] Please refer to it again. Figure 1 In one embodiment, the gas path structure 10 further includes a flow control module 150 connected to the output end to regulate the flow rate of the gas passing through it. A detection branch 140 is connected between the pressure reducing valve 130 and the flow control module 150. After the pressure reducing valve 130 outputs gas at the expected pressure, the flow control module 150 can regulate the flow rate of that gas to control the gas flow rate delivered to the ventilator user 20, thereby meeting the ventilation requirements.

[0036] In one embodiment, the flow control module 150 includes a proportional valve 151, a flow stabilizer 152, and an intake flow sensor 153. The proportional valve 151 is used to regulate the flow rate of the gas passing through it. The flow stabilizer 152 is used to reduce the turbulence of the gas passing through it. Along the gas flow direction within the gas path structure 10, the proportional valve 151, the flow stabilizer 152, and the intake flow sensor 153 are connected sequentially. Therefore, the gas output from the proportional valve 151 is only detected by the intake flow sensor 153 after the flow stabilizer 152 has stabilized its flow, thus improving the accuracy of the intake flow sensor 153. It is easy to understand that the proportional valve 151 regulates the gas flow rate; therefore, the turbulence of the internal flow state of the gas increases after passing through the proportional valve 151. At this time, there will be several unstable flow streams with different flow directions and velocities within the gas. This embodiment reduces the turbulence of the gas by setting the flow stabilizer 152, enabling the intake sensor to detect accurate and stable values.

[0037] In one embodiment, the flow stabilizer 152 is a sintered filter. A sintered filter is a type of filter made of granular glass, quartz, ceramic, metal, or plastic sintered at high temperatures and possessing micropores. Compared to a traditional grid-type flow stabilizer 152, the sintered filter has smaller micropore sizes, resulting in better flow stabilization. Simultaneously, as a filter, it also functions to filter fluids. In short, this embodiment, by using a sintered filter as a flow stabilizer, not only achieves better flow stabilization but also filters gases. The flow stabilizer 152 can be a copper sintered filter or a steel sintered filter.

[0038] Of course, in other embodiments, the current stabilizer 152 may also use other components with current stabilization function, such as a current stabilizer tube with a grid.

[0039] Please refer to it again. Figure 1 In one embodiment, the gas path structure 10 includes an intake path 100, wherein the gas source 110, the pressure reducing valve 130, the detection branch 140, and the flow control module 150 are components of the intake path 100. The intake path 100 also includes components such as a gas source pressure detector 121, a pressure relief valve 122, a gas source filter 123, a one-way valve 124, and an intake air resistance 154.

[0040] The gas source pressure detector 121 and the pressure relief valve 122 are connected between the gas source 110 and the pressure reducing valve 130, that is, they are connected at the outlet of the gas source 110. The gas source pressure detector 121 is used to detect the pressure at the outlet of the gas source 110. The pressure relief valve 122 is used to open to release pressure when the pressure at the outlet of the gas source 110 exceeds a set threshold.

[0041] The gas source filter 123 is connected between the gas source 110 and the pressure reducing valve 130 to filter impurities in the gas output from the gas source 110, preventing impurities from damaging the pressure reducing valve 130 and the proportional valve 151. Further, the gas source filter 123 can be located between the pressure relief valve 122 and the pressure reducing valve 130.

[0042] A one-way valve 124 is connected between the gas source filter 123 and the pressure reducing valve 130 to prevent gas backflow.

[0043] The intake air resistance 154 is connected to the end of the flow stabilizer 152 closest to the user 20. The intake flow sensor 153 can be a differential pressure flow sensor. The intake flow sensor 153 detects the flow rate of the gas flowing through it by detecting the pressure at the front and rear ends of the intake air resistance 154. It is easy to understand that when the gas flows through the intake air resistance 154, a throttling effect occurs, and a pressure difference will be generated at the front and rear ends of the intake air resistance 154. The differential pressure flow sensor can determine the gas flow rate by detecting this pressure difference.

[0044] Combination Figure 1In other words, the intake path 100 may include, in sequence, an air source 110, an air source pressure detector 121, a pressure relief valve 122 (the pressure relief valve 122 and the air source pressure detector 121 are not distinguished by their order), an air source filter 123, a one-way valve 124, a pressure reducing valve 130, a detection branch 140, a proportional valve 151, a flow stabilizer 152, and an intake flow sensor 153. It should be noted that this is not a limitation on the connection order of the components included in the intake path 100, but merely an example illustrating the connection positional relationship of the components included in the intake path 100. The positions of each component can be adaptively adjusted and interchanged while meeting the desired performance. The description of the oxygen branch 101 and the air branch 102 follows the same principle and will not be repeated here.

[0045] Please see Figure 1 In one embodiment, the intake path 100 may include an oxygen branch 101 and an air branch 102, and both the oxygen branch 101 and the air branch 102 may include some or all of the components included in the intake path 100 as described in the various embodiments.

[0046] The oxygen branch 101 may include a gas source 110, a pressure reducing valve 130, a detection branch 140, and a flow control module 150 connected in series. Through the detection branch 140, the pressure within the oxygen branch 101 can be regulated without disassembling the pressure reducing valve 130. Simultaneously, the flow control module 150 can control the oxygen content output from the oxygen branch 101. Combined with the air content delivered by the air branch 102, this allows for comprehensive adjustment of the oxygen concentration in the gas supplied by the ventilator and adjustment of the tidal volume. The gas source 110 in the oxygen branch 101 is the oxygen source 111.

[0047] Furthermore, the flow control module 150 of the oxygen branch 101 may also include the proportional valve 151, the flow stabilizer 152, and the inhalation pressure detector 162.

[0048] Similarly, the air branch 102 may also include an air source 110, a pressure reducing valve 130, a detection branch 140, and a flow control module 150 connected in series. Through the detection branch 140 in the air branch 102, the pressure within the air branch 102 can be adjusted without disassembling the pressure reducing valve 130. Correspondingly, by adjusting the air flow rate through the flow control module 150 in the air branch 102, and in conjunction with adjusting the oxygen flow rate through the flow control module 150 in the oxygen branch 101, the oxygen concentration in the gas supplied by the ventilator can be adjusted, as well as the tidal volume. The air source 110 in the air branch 102 is the air source 112.

[0049] The flow control module 150 of the air branch 102 may also include the proportional valve 151, the flow stabilizer 152 and the intake pressure detector 162.

[0050] Furthermore, both the oxygen branch 101 and the air branch 102 may include the gas source pressure detector 121, pressure relief valve 122, gas source filter 123, one-way valve 124, and intake air resistance 154, etc., as can be seen in the embodiments described above, and will not be repeated here.

[0051] In one embodiment, the inhalation path 100 further includes a mixer 161, an inhalation pressure detector 162, and an oxygen concentration sensor 163.

[0052] The outputs of oxygen branch 101 and air branch 102 converge at mixer 161, where oxygen and air are mixed to form a gas for the user 20 to breathe.

[0053] Along the gas flow direction in the intake path 100, the mixer 161, the intake pressure detector 162, and the oxygen concentration sensor 163 are connected in sequence. The intake pressure detector 162 is used to detect the pressure of the mixed gas, and the oxygen concentration sensor 163 is used to detect the oxygen concentration in the mixed gas, so that the flow control module 150 in the oxygen branch 101 and the flow control module 150 in the air branch 102 can perform feedback adjustment.

[0054] In one embodiment, the intake path 100 further includes a safety branch 103, one end of which is connected between the mixer 161 and the user 20, and the other end of which is connected to the external environment. The safety branch 103 is used to open when the pressure of the mixed gas exceeds a safety threshold to prevent high-pressure injury to the user 20. Further, the safety branch 103 may include an electronic safety valve 172 and a mechanical safety valve 171. Further, the end of the safety branch 103 connected to the outlet of the mixer 161 may be located between the intake pressure detector 162 and the oxygen concentration sensor 163.

[0055] Please refer to it again. Figure 1 In one embodiment, the gas path structure 10 further includes an exhalation path 200 and a purge path 300, the purge path 300 being used to purge condensate from the exhalation path 200. The exhalation path 200 connects the user 20 to the outside to expel the gas exhaled by the user 20. The exhalation path 200 may include an electronic PEEP valve 210, an exhalation valve 220, and an exhalation flow sensor 230. The exhalation flow sensor 230 is used to detect the gas flow rate in the exhalation path 200; the exhalation flow sensor 230 may also be a differential pressure flow sensor. The electronic PEEP valve 210 and the exhalation valve 220 are used to control the PEEP value, and the exhaled gas is discharged from the exhalation valve 220.

[0056] The purge path 300 connects the air source 110 to the expiratory flow sensor 230. The purge path 300 is equipped with a purge switch valve 320 for shutting off or opening the purge path 300. Taking the expiratory flow sensor 230 as a differential pressure flow sensor as an example, the moist air exhaled by the user 20 easily condenses when it comes into contact with the diaphragm of the differential pressure flow sensor, producing condensate water. This condensate water will affect the detection accuracy of the differential pressure flow sensor. In this embodiment, the air provided by the air source 110 forms a purge airflow, which can blow off the condensate water adhering to the diaphragm and drive the condensate water to be discharged along with the exhaled air. Therefore, the detection accuracy of the expiratory flow sensor 230 can be guaranteed.

[0057] In one embodiment, the purge path 300 includes a selection valve 310. The purge path 300 can be simultaneously connected to the gas source 110 of the oxygen branch 101 and the gas source 110 of the air branch 102. The selection valve 310 selects the appropriate gas provided by the gas source 110 as the purge air.

[0058] In one embodiment, the expiratory pathway 200 further includes an expiratory pressure detector 240 to detect the pressure of the exhaled gas.

[0059] Please refer to it again. Figure 1 In one embodiment, the air passage structure 10 further includes an atomization path 400, and a purge path 300 is also connected to the atomization path 400. The purge air can provide power to carry the atomized aerosol into the user 20 for inhalation. Furthermore, for some atomizers 420, the purge air can also provide power to atomize the medium to assist in the atomization of the medium.

[0060] In one embodiment, the atomization path 400 includes an atomization switching valve 410, which can control the opening and closing of the atomization path 400.

[0061] In one embodiment, the air circuit structure 10 also includes multiple air resistors. By reasonably setting the position of each air resistor, the flow rate and pressure of each branch in the circuit can be adjusted.

[0062] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0063] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A gas path structure for gas delivery of a respirator, characterized by, The gas path structure includes: Gas source; A pressure reducing valve, comprising an input end and an output end, wherein the input end is connected to the gas source and the output end is used to connect to the user; A detection branch is connected to the output end of the pressure reducing valve and is used to detect the pressure at the output end. The detection branch includes a delivery tube, a pressure detector, and a shut-off valve. One end of the delivery tube is connected to the output end, and the other end of the delivery tube is used to connect to the outside of the ventilator. The pressure detector is located on the delivery tube to detect the pressure inside the tube, and the shut-off valve is located on the delivery tube to cut off the gas delivery through the delivery tube. The airway structure is located inside the housing of the ventilator, and the end of the detection branch furthest from the pressure reducing valve is embedded in the housing.

2. The gas path structure according to claim 1, characterized in that, The gas path structure also includes a flow control module, which is connected to the output end to regulate the flow rate of the gas. The detection branch is connected between the pressure reducing valve and the flow control module.

3. The air passage structure according to claim 2, wherein The flow control module includes a proportional valve, a flow stabilizer, and an intake flow sensor. The flow stabilizer is used to reduce the turbulence of the gas flowing through it. The proportional valve, the flow stabilizer, and the intake flow sensor are connected in sequence along the gas flow direction within the gas path structure.

4. The air passage structure according to claim 3, wherein The flow stabilizer is a sintered filter.

5. The air passage structure according to claim 3, wherein The gas path structure includes an intake path, which includes an oxygen branch. The oxygen branch includes the gas source, the pressure reducing valve, the detection branch, and the flow control module, which are connected in series.

6. The air passage structure according to claim 5, wherein The intake path also includes an air branch, which in turn includes the air source, the pressure reducing valve, the detection branch, and the flow control module connected in series.

7. The air passage structure according to claim 6, wherein The intake path also includes a mixer, and the output ends of the oxygen branch and the air branch converge at the mixer; The intake path also includes a safety branch, one end of which is connected between the mixer and the user, and the other end of which is connected to the external environment. The safety branch is used to activate when the gas pressure after mixing is greater than a safety threshold.

8. The air passage structure according to claim 1, wherein The gas path structure also includes an exhalation path and a purge path. The exhalation path includes an exhalation flow sensor, and the purge path connects the gas source and the exhalation flow sensor. The purge path is equipped with a purge switch valve for cutting off or opening the purge path.

9. The air passage structure according to claim 8, wherein The gas path structure also includes an atomizing path, and the purging path is also connected to the atomizing path.

10. A breathing machine characterized by, The ventilator includes the airway structure as described in any one of claims 1 to 9.

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