CN117942480A - Gas circuit structure and breathing machine - Google Patents

Abstract

The application relates to a gas circuit structure and a breathing machine, wherein the gas circuit structure is used for conveying gas of the breathing machine, the gas circuit structure comprises a gas source, a pressure reducing valve and a detection branch, the pressure reducing valve comprises an input end and an output end, the input end is connected with the gas source, and the output end is used for communicating a user; the detection branch is connected to the output end of the pressure reducing valve, and the detection branch is used for detecting the pressure of the output end. The detection branch is connected to the output end of the pressure reducing valve, so that the detection branch can detect the pressure of the output end in real time, and a reference is provided for pressure regulation of the pressure reducing valve. Compared with the prior art that the pressure of the output end of the pressure reducing valve can be detected by arranging the detection branch circuit which can be used for independently regulating the pressure after the pressure reducing valve is detached, the pressure of the pressure reducing valve can be regulated under the condition that the pressure reducing valve is not detached, and therefore convenience in pressure regulation in the process of factory detection, fault maintenance, fault troubleshooting, maintenance and the like is improved. The breathing machine comprises the air circuit structure, and is more convenient when the pressure of the pressure reducing valve is regulated.

Description

Gas circuit structure and breathing machine

Technical Field

The application relates to the technical field of respirators, in particular to a gas circuit structure and a respirator.

Background

The breathing machine is a medical instrument capable of partially or completely replacing autonomous ventilation of a human body, and comprises a gas storage tank and a pressure reducing valve, wherein the gas storage tank is used for providing ventilated high-pressure gas, and the pressure reducing valve is connected to an outlet of the gas storage tank and is used for reducing the high-pressure gas into gas with expected pressure. The pressure of the gas supplied by different gas reservoirs is different, so that pressure regulation of the pressure reducing valve is generally required.

In the current breathing machine, when the pressure of the output end of the pressure reducing valve does not meet the expected pressure, the pressure reducing valve needs to be disassembled, and the pressure is regulated by utilizing an independent tool, so that the operation is complex.

Disclosure of Invention

Based on the above, it is necessary to provide a gas path structure and a ventilator, aiming at the problem of complicated pressure regulating operation of a pressure reducing valve in the ventilator.

The application provides a gas circuit structure, which is used for gas delivery of a breathing machine and comprises the following components:

A gas source;

The pressure reducing valve comprises an input end and an output end, the input end is connected with the air source, and the output end is used for communicating a user;

the detection branch is connected with the output end of the pressure reducing valve and used for detecting the pressure of the output end.

In one embodiment, the detection branch comprises a conveying pipe, a pressure detector and a stop valve, one end of the conveying pipe is communicated with the output end, the other end of the conveying pipe is communicated with the outside of the breathing machine, the pressure detector is arranged on the conveying pipe to detect the pressure in the pipe, the stop valve is arranged on the conveying pipe, and the stop valve is used for stopping gas conveying of the conveying pipe.

In one embodiment, the gas circuit structure further includes a flow control module connected to the output end to regulate the flow of the gas flowing therethrough, and the detection branch is connected between the pressure reducing valve and the flow control module.

In one embodiment, the flow control module comprises a proportional valve, a flow stabilizing piece and an inhalation flow sensor, wherein the flow stabilizing piece is used for reducing the confusion degree of the gas flowing through; and the proportional valve, the steady flow piece and the air suction flow sensor are sequentially connected along the flow direction of the air in the air path structure.

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

In one embodiment, the gas circuit structure includes a gas suction circuit, the gas suction circuit includes an oxygen branch circuit, and the oxygen branch circuit includes the gas source, the pressure reducing valve, the detection branch circuit and the flow control module which are sequentially connected in series.

In one embodiment, the suction line further comprises an air branch, and the air branch also comprises the air source, the pressure reducing valve, the detection branch and the flow control module which are sequentially connected in series.

In one embodiment, the air path structure further comprises an air-breathing path and a purging path, wherein the air-breathing path comprises an air-breathing flow sensor, and the purging path is communicated with the air source and the air-breathing flow sensor; the purge path is provided with a purge switch valve for cutting off or opening the purge path.

In one embodiment, the air path structure further comprises an atomization path, and the purge path is further in communication with the atomization path.

The application also provides a breathing machine, which comprises the air path structure.

In the gas circuit structure, the detection branch is connected to the output end of the pressure reducing valve, so that the detection branch can detect the pressure of the output end in real time, and a reference is provided for pressure regulation of the pressure reducing valve. And then, after the gas circuit structure is assembled with other structures included in the breathing machine, the pressure value of the gas output by the gas source under the decompression action of the decompression valve can be detected through the detection branch. And when the pressure of the output end of the pressure reducing valve does not meet the expected pressure, the pressure of the output end can be adjusted in a feedback mode according to the pressure detected by the detection branch so as to be adjusted to the expected pressure. That is, compared with the prior art that the pressure of the output end of the pressure reducing valve needs to be regulated independently after the pressure reducing valve is disassembled, the gas circuit structure provided by the application can regulate the pressure of the pressure reducing valve under the condition that the pressure reducing valve does not need to be disassembled by arranging the detection branch circuit capable of detecting the pressure of the output end of the pressure reducing valve, so that the convenience of pressure regulation in the processes of factory detection, fault maintenance, fault investigation, maintenance and the like is improved.

Drawings

Fig. 1 is a schematic circuit diagram of a ventilator according to an embodiment of the present application.

Fig. 2 is a schematic block diagram of a detection branch according to an embodiment of the present application.

Reference numerals: 10. an air path structure; 100. an air suction path; 101. an oxygen branch; 102. an air branch; 103. a safety branch; 110. a gas source; 111. an oxygen source; 112. an air source; 121. an air source pressure detector; 122. a pressure release valve; 123. an air source filter; 124. a one-way valve; 130. a pressure reducing valve; 140. a detection branch; 150. a flow control module; 151. a proportional valve; 152. a steady flow member; 153. an inhalation flow sensor; 154. inhalation air resistance; 161. a mixer; 162. an inhalation pressure detector; 163. an oxygen concentration sensor; 171. a mechanical safety valve; 172. an electronic safety valve; 200. a breathing circuit; 210. an electronic PEEP valve; 220. an exhalation valve; 230. an exhalation flow sensor; 240. an exhalation pressure detector; 300. blowing and sweeping a road; 310. a selection valve; 320. purging the switch valve; 400. an atomization path; 410. an atomization switch valve; 420. an atomizer; 20. and (3) a user.

Detailed Description

In order that the above objects, features and advantages of the application will be readily understood, a more particular description of the application will be rendered by reference to the appended drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. The present application may be embodied in many other forms than described herein and similarly modified by those skilled in the art without departing from the spirit of the application, whereby the application is not limited to the specific embodiments disclosed below.

In the description of the present application, it should be understood that, if any, these terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., are used herein with respect to the orientation or positional relationship shown in the drawings, these terms refer to the orientation or positional relationship for convenience of description and simplicity of description only, and do not indicate or imply that the apparatus or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the application.

Furthermore, the terms "first," "second," and the like, if any, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present application, the terms "plurality" and "a plurality" if any, mean at least two, such as two, three, etc., unless specifically defined otherwise.

In the present application, unless explicitly stated and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly. For example, the two parts can be fixedly connected, detachably connected or integrated; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present application, unless expressly stated or limited otherwise, the meaning of a first feature being "on" or "off" a second feature, and the like, is that the first and second features are either in direct contact or in indirect contact through an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

It will be understood that if an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or intervening elements may also be present. If an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein, if any, are for descriptive purposes only and do not represent a unique embodiment.

Referring to fig. 1, fig. 1 is a schematic circuit diagram of a ventilator according to an embodiment of the present application, where the ventilator (not shown in the drawings, the following description is the same) includes a gas path structure 10, and the gas path structure 10 is used for gas delivery of the ventilator.

In one embodiment, the air circuit structure 10 includes an air source 110, a pressure reducing valve 130, and a detecting branch 140, wherein the pressure reducing valve 130 includes an input end and an output end, the input end is connected with the air source 110, and the output end is used for communicating with the user 20. The detecting branch 140 is connected to the output end of the pressure reducing valve 130, and the detecting branch 140 is used for detecting the pressure of the output end.

In the above-mentioned air circuit structure 10, the detecting branch 140 is connected to the output end of the pressure reducing valve 130, so the detecting branch 140 can detect the pressure at the output end in real time, and provide a reference for pressure regulation of the pressure reducing valve 130. Then, after the air path structure 10 is assembled with other structures included in the ventilator, the pressure value of the air output by the air source 110 under the decompression action of the decompression valve 130 can be detected through the detection branch 140. And, when the pressure at the output end of the pressure reducing valve 130 does not meet the expectations, the pressure at the output end of the pressure reducing valve 130 may be feedback-adjusted according to the pressure detected by the detection branch 140 to adjust the pressure at the output end to the expected pressure. That is, compared with the conventional technology in which the pressure-regulating valve 130 needs to be disassembled and then independently regulated, the gas circuit structure 10 provided by the application can regulate the pressure of the pressure-regulating valve 130 without disassembling the pressure-regulating valve 130 by arranging the detection branch 140 capable of detecting the pressure of the output end of the pressure-regulating valve 130, so that convenience in pressure regulation in the processes of factory detection, fault maintenance, fault investigation, maintenance and the like is improved.

Further, the above-mentioned gas circuit structure 10 is so configured that pressure can be regulated without disassembling the pressure reducing valve 130, so that the pressure reducing valve 130 can be regulated after the assembly of the breathing machine is basically completed, and the probability of occurrence of a pre-regulation failure caused by mistakenly touching the pressure reducing valve 130 in the assembly process is reduced. In other words, the pressure of the pressure reducing valve 130 is regulated after the pressure reducing valve 130 is assembled, and the effectiveness of the pressure regulation can be improved.

Furthermore, the gas path structure 10 leads out a detecting branch 140 on the gas conveying path, so that the pressure detecting mode at the output end of the pressure reducing valve 130 is simpler, and the structure required by pressure detection is simpler. For example, if a pressure detector is built in the pressure reducing valve 130 to detect the pressure at the output end, the pressure detector needs to be integrated in the pressure reducing valve 130, which increases the cost of the pressure reducing valve 130 and the structural volume of the pressure reducing valve 130, making assembly inconvenient. Meanwhile, since the installation position of the pressure reducing valve 130 is limited, the operation of the pressure reducing valve 130 is inconvenient.

Still further, the detection branch 140 may extend in a direction away from the pressure relief valve 130. For example, the ventilator further includes a housing, the air path structure 10 is disposed in the housing, and an end of the detecting branch 140 away from the pressure reducing valve 130 may be embedded in the housing, so as to facilitate an operation from an outside of the housing. Of course, in other embodiments, the detection branch 140 may be disposed at other locations of the ventilator that are convenient for operation.

Referring to fig. 2, in one embodiment, the detecting branch 140 includes a conveying pipe, a pressure detector, and a stop valve, one end of the conveying pipe is connected to the output end, and the other end of the conveying pipe is used to connect to the exterior of the ventilator. The pressure detector is arranged on the conveying pipe fitting to detect the pressure in the pipe, the stop valve is arranged on the conveying pipe fitting, and the stop valve is used for stopping the gas conveying of the conveying pipe fitting. When the pressure of the pressure reducing valve 130 needs to be regulated, the stop valve is opened to allow the delivery pipe to communicate with the output end to have the same pressure, and the pressure detector can detect the pressure of the output end. When the pressure of the pressure relief valve 130 does not need to be detected, the shut-off valve may be closed to shut off the delivery tubing, reducing the negative impact of the delivery tubing on ventilator ventilation.

Referring to fig. 1 again, in one embodiment, the gas circuit structure 10 further includes a flow control module 150, the flow control module 150 is connected to the output end to regulate the flow of the gas flowing therethrough, and the detection branch 140 is connected between the pressure reducing valve 130 and the flow control module 150. After the pressure relief valve 130 outputs the gas at the desired pressure, the flow control module 150 can adjust the flow of the gas to control the flow of the gas to the ventilator user 20 to meet ventilation needs.

In one embodiment, the flow control module 150 includes a proportional valve 151, a flow stabilizer 152, and an inspiratory flow sensor 153, the proportional valve 151 being configured to regulate the flow of gas therethrough. The flow stabilizer 152 serves to reduce the turbulence of the gas flowing therethrough. Along the flow direction of the gas in the gas circuit structure 10, the proportional valve 151, the steady flow member 152 and the air suction flow sensor 153 are sequentially connected, so that the gas output by the proportional valve 151 is only detected by the air suction flow sensor 153 after the steady flow of the steady flow member 152, and the accuracy of the air suction flow sensor 153 can be improved. It is easy to understand that when the proportional valve 151 has the function of adjusting the flow rate of the gas, the turbulence of the flow state of the gas inside the proportional valve 151 will rise after the gas flows through the proportional valve 151, and then a plurality of unstable streams with different flow directions and flow speeds will exist in the gas. In this embodiment, the flow stabilizing member 152 is provided to reduce the turbulence of the gas, so that the inhalation sensor can detect an accurate and stable value.

In one embodiment, the flow stabilizer 152 is a sintered filter. Sintered filters are a type of filter which is sintered at high temperature from granular glass, quartz, ceramics, metal or plastics, etc., and has micropores. Compared with the traditional grid-type steady flow piece 152, the micropore aperture of the sintering filter is smaller, so that the steady flow effect is better. At the same time, as a filter, it can also function as a filter for the fluid. In short, the embodiment not only has better steady flow effect, but also has the effect of filtering gas by adopting the sintering filter as the current stabilizer. The flow stabilizer 152 may be a copper sintered filter or a steel sintered filter.

Of course, in other embodiments, other components with a stabilizing effect, such as a stabilizing tube with a grid, etc., may be used for the stabilizing member 152.

Referring again to fig. 1, in one embodiment, the air circuit structure 10 includes an air suction circuit 100, and the air source 110, the pressure reducing valve 130, the detecting branch 140, and the flow control module 150 are components of the air suction circuit 100. The suction line 100 further includes a source pressure detector 121, a relief valve 122, a source filter 123, a check valve 124, and a suction resistor 154.

The air source pressure detector 121 and the relief valve 122 are connected between the air source 110 and the relief valve 130, i.e. both are in communication at the outlet of the air source 110. The gas source pressure detector 121 is used to detect the pressure at the outlet of the gas source 110. Relief valve 122 is operable to open to relieve pressure when the pressure at the outlet of gas source 110 is greater than a set threshold.

The gas source filter 123 is connected between the gas source 110 and the pressure reducing valve 130, and is used for filtering impurities in the gas output by the gas source 110, and preventing the pressure reducing valve 130 and the proportional valve 151 from being damaged by the impurities. Further, an air source filter 123 may be provided between the relief valve 122 and the relief valve 130.

Check valve 124 is connected between gas source filter 123 and pressure relief valve 130 to prevent back flow of gas.

An inspiratory air resistor 154 is coupled to an end of the stabilizer 152 proximate to the user 20. The suction flow rate sensor 153 may be a differential pressure type flow rate sensor, and the suction flow rate sensor 153 detects the flow rate of the gas flowing therethrough by detecting the pressures at the front and rear ends of the suction air resistor 154. It will be readily appreciated that a restriction is created as the gas flows through the suction air resistor 154, and a pressure differential will be created across the front and rear ends of the suction air resistor 154, which pressure differential flow sensor will detect to derive the gas flow.

In connection with fig. 1, that is, the suction line 100 may include a gas source 110, a gas source pressure detector 121, a pressure relief valve 122 (the pressure relief valve 122 is not separated from the gas source pressure detector 121), a gas source filter 123, a check valve 124, a pressure relief valve 130, a detection branch 140, a proportional valve 151, a flow stabilizer 152, and a suction flow sensor 153, which are sequentially connected. The connection order of the parts included in the intake passage 100 is not limited, but the connection positional relationship of the parts included in the intake passage 100 is described as a specific example, and the positions of the parts may be adaptively adjusted and exchanged when the use effect is satisfied. The same applies to the oxygen branch 101 and the air branch 102, and thus the description thereof will be omitted.

Referring to fig. 1, in one embodiment, the air intake path 100 may include an oxygen branch 101 and an air branch 102, and the oxygen branch 101 and the air branch 102 may include some or all of the components included in the air intake path 100 according to the embodiments.

That is, oxygen branch 101 may include a gas source 110, a pressure relief valve 130, a detection branch 140, and a flow control module 150 connected in series in that order. By means of the detection branch 140 in the oxygen branch 101, the pressure in the oxygen branch 101 can be regulated without dismantling the pressure reducing valve 130. Meanwhile, the flow control module 150 can control the oxygen content output by the oxygen branch 101, and can comprehensively adjust the oxygen concentration in the gas supplied by the breathing machine and adjust the tidal volume in combination with the content of the air conveyed by the air branch 102. The gas source 110 in the oxygen branch 101 is the oxygen source 111.

Further, the flow control module 150 of the oxygen branch 101 may also include the proportional valve 151, the flow stabilizer 152, and the inspiratory pressure detector 162.

Similarly, air branch 102 may also include an air source 110, a pressure relief valve 130, a detection branch 140, and a flow control module 150 connected in series. By means of the detection branch 140 in the air branch 102, the pressure in the air branch 102 can be regulated without dismantling the pressure relief valve 130. In response to the above, the flow rate of air is adjusted by the flow rate control module 150 in the air branch 102, and the flow rate of oxygen is adjusted by the flow rate control module 150 in the oxygen branch 101, so that the oxygen concentration in the gas supplied from the ventilator and the tidal volume can be adjusted. Air source 110 in air branch 102 is air source 112.

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

Further, the oxygen branch 101 and the air branch 102 may also include the air source pressure detector 121, the pressure relief valve 122, the air source filter 123, the check valve 124, the air suction resistor 154, etc., which are described in the foregoing embodiments and are not repeated here.

In one embodiment, the inspiratory circuit 100 further comprises a mixer 161, an inspiratory pressure detector 162, and an oxygen concentration sensor 163.

The output ends of the oxygen branch 101 and the air branch 102 meet at a mixer 161, and the oxygen and air meet and mix to form a gas for the user 20 to breathe.

Along the flow direction of the gas in the gas suction path 100, the mixer 161, the gas suction pressure detector 162 and the oxygen concentration sensor 163 are sequentially connected, the gas suction pressure detector 162 is used for detecting the pressure of the mixed gas, and the oxygen concentration sensor 163 is used for detecting 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.

In one embodiment, the inhalation flow path 100 further comprises a safety branch 103, one end of the safety branch 103 being connected between the mixer 161 and the user 20, the other end of the safety branch 103 being in communication with the external environment. The safety branch 103 is used to open when the mixed gas pressure is greater than a safety threshold to avoid 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 that is connected to the outlet of the mixer 161 may be located between the suction pressure detector 162 and the oxygen concentration sensor 163.

Referring again to fig. 1, in one embodiment, the air circuit structure 10 further includes an air-breathing circuit 200 and a purge circuit 300, wherein the purge circuit 300 is used for purging condensed water in the air-breathing circuit 200. The breathing circuit 200 communicates the user 20 with the outside to direct out the gas exhaled by the user 20. The exhalation circuit 200 may include an electronic PEEP valve 210, an exhalation valve 220, and an exhalation flow sensor 230. The expiratory flow sensor 230 is used to detect the flow of gas in the expiratory circuit 200, and the expiratory flow sensor 230 may be a differential pressure flow sensor. The electronic PEEP valve 210 and the exhalation valve 220 are used to control the PEEP value, and exhaled air is exhausted from the exhalation valve 220.

Purge path 300 communicates air source 110 with exhalation flow sensor 230. The purge path 300 is provided with a purge switch valve 320 for cutting off or opening the purge path 300. Taking the exhalation flow sensor 230 as a differential pressure flow sensor as an example, when the wet gas exhaled by the user 20 hits the diaphragm of the differential pressure flow sensor, condensed water is easily condensed, and the condensed water affects the detection accuracy of the differential pressure flow sensor. The present embodiment forms a purge wind using the gas provided from the gas source 110, and is capable of blowing off the condensed water attached to the membrane and driving the condensed water to be discharged together with the exhaled gas. Thereby, the detection accuracy of the expiratory flow sensor 230 can be ensured.

In one embodiment, purge path 300 includes a selector valve 310. Purge path 300 may be in communication with both source 110 of oxygen branch 101 and source 110 of air branch 102. The appropriate source 110 may be selected as the purge wind by selector valve 310.

In one embodiment, the exhalation path 200 further includes an exhalation pressure detector 240 to detect the pressure of the exhaled gas.

Referring again to fig. 1, in one embodiment, the air circuit structure 10 further includes an atomizing circuit 400, and the purge circuit 300 is further in communication with the atomizing circuit 400. The purge wind can be powered to carry the atomized aerosol for inhalation by the user 20. Also, for some atomizers 420, the purge wind may also power the atomization of the medium to be atomized to assist in the atomization of the medium to be atomized.

In one embodiment, the atomizing circuit 400 includes an atomizing switch valve 410, and the opening and closing of the atomizing circuit 400 can be controlled by the atomizing switch valve 410.

In one embodiment, the air circuit structure 10 further includes a plurality of air resistors, and by reasonably setting the positions of the air resistors, the flow and the pressure of each branch part in the loop can be adjusted.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples illustrate only a few embodiments of the application, which are described in detail and are not to be construed as limiting the scope of the claims. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the application, which are all within the scope of the application. Accordingly, the scope of protection of the present application is to be determined by the appended claims.

Claims (10)

1. An air circuit structure for gas delivery of a ventilator, the air circuit structure comprising:

A gas source;

The pressure reducing valve comprises an input end and an output end, the input end is connected with the air source, and the output end is used for communicating a user;

the detection branch is connected with the output end of the pressure reducing valve and used for detecting the pressure of the output end.

2. The gas circuit structure according to claim 1, wherein the detection branch includes a conveying pipe, a pressure detector and a stop valve, one end of the conveying pipe is communicated with the output end, the other end of the conveying pipe is used for being communicated with the outside of the breathing machine, the pressure detector is arranged on the conveying pipe to detect the pressure in the pipe, the stop valve is arranged on the conveying pipe, and the stop valve is used for stopping gas conveying of the conveying pipe.

3. A gas circuit arrangement according to claim 2, further comprising a flow control module connected to the output for regulating the flow of gas therethrough, the detection branch being connected between the pressure relief valve and the flow control module.

4. A gas circuit structure according to claim 3, wherein the flow control module comprises a proportional valve, a flow stabilizing member and an inhalation flow sensor, the flow stabilizing member being adapted to reduce the degree of turbulence of the gas flowing therethrough; and the proportional valve, the steady flow piece and the air suction flow sensor are sequentially connected along the flow direction of the air in the air path structure.

5. A gas circuit structure according to claim 4, wherein the flow stabilizing member is a sintered filter.

6. The gas circuit structure of claim 4, comprising a gas suction circuit comprising an oxygen branch comprising the gas source, the pressure relief valve, the detection branch, and the flow control module connected in series in sequence.

7. A gas circuit structure according to claim 6, wherein the suction circuit further comprises an air branch, the air branch also comprising the gas source, the pressure relief valve, the detection branch and the flow control module connected in series in sequence.

8. The air circuit structure of claim 1, further comprising an air circuit including an air flow sensor and a purge circuit communicating the air source with the air flow sensor; the purge path is provided with a purge switch valve for cutting off or opening the purge path.

9. A gas circuit structure according to claim 8, further comprising an atomizing circuit, the purge circuit further in communication with the atomizing circuit.

10. A ventilator comprising a gas circuit arrangement as claimed in any one of claims 1 to 9.