Breath test filter device, mouthpiece and breath test method for preventing cross contamination

Abstract

The present invention provides a breath detection filter device that prevents cross contamination, a mouthpiece used therewith, and a breath detection method. The filter device includes a mouthpiece and a device body, and the mouthpiece is detachably connected to the device body. The mouthpiece includes an exhalation channel and an inhalation channel, a one-way valve is provided on the inhalation channel, and an opening and closing device is provided on the exhalation channel. The exhalation channel and the inhalation channel of the mouthpiece correspond to the exhalation channel and the inhalation channel of the device body respectively and are tightly connected without leakage. The mouthpiece in the filter device of the present invention is for single use, which can avoid contamination of the inhalation channel of the device body used by multiple people, so as to achieve the purpose of preventing cross contamination during the exhalation detection process of exhaled nitric oxide, etc., and is very suitable for promotion and application in clinical practice.

Description

Technical Field

[0001] The present invention relates to the field of exhaled gas detection, and in particular to a filtering device, a mouthpiece and a detection method for preventing cross contamination. Background Art

[0002] As early as the early 18th century, researchers discovered that differences in human exhaled breath odor could indicate the onset of certain diseases. With the advancement of modern medical technology, more and more disease-related markers have been discovered in exhaled breath. Exhaled breath testing is now widely used in clinical research and diagnosis, covering volatile organic compounds (VOCs), exhaled breath condensate (EBC), and particulate matter in exhaled breath. Organic compounds in exhaled breath currently used in clinical testing include nitric oxide, carbon monoxide, hydrogen, methane, ammonia, hydrogen sulfide, oxygen, and carbon dioxide.

[0003] Exhaled nitric oxide (FeNO), as an internationally recognized non-invasive marker for eosinophilic (EOS) airway inflammation, has been widely used in clinical testing. According to the technical standards for exhaled nitric oxide testing jointly formulated by the American Thoracic Society (ATS) and the European Respiratory Society (ERS) in 2005, it is recommended to inhale air without nitric oxide (<5ppb) before testing, and then exhale for testing to avoid the influence of nitric oxide in the ambient gas on the test results. At present, the existing technology generally sets a filter device containing nitric oxide removal material in the inhalation path to achieve the purpose of inhaling air without nitric oxide (<5ppb); at the same time, a filter device is set in the exhalation path to filter food residues, particulate matter, droplets, bacteria and other pollutants to avoid contamination of the detection channel and equipment, but there is still a risk of viruses or small molecule pollutants passing through.

[0004] A Chinese patent with announcement number CN104244819B discloses a handheld part and an exhalation analysis device, including an inhalation hole, an inhalation path, an exhalation discharge part, an exhalation path and a bend. The bend reduces the risk of damage to the pipeline connecting the analysis body during use. The device is provided with a filter part in the inhalation path, and two sets of one-way valves are provided before and after the filter part for opening and closing the filter part during inhalation or exhalation. The disadvantage of this technology is that the inhalation inlet part 11 and the exhalation discharge part 13 of the device are actually the same gas circulation part, and the second inhalation path and the exhaust path are actually the same gas circulation part. Since there is a common part between the exhalation path and the inhalation path in the device, and the handheld part is used multiple times, there is a risk of cross-contamination when multiple people share one handheld part.

[0005] Chinese patent publication number CN105388278B discloses a handheld respiratory filter device with an inhalation path and an exhalation path. The inhalation path consists of an opening, a filter chamber, a diaphragm containing a one-way valve, a moistening paper, and a mouthpiece. During inhalation, the one-way valve opens, allowing air to enter the body; during exhalation, the one-way valve closes, preventing air from entering the filter chamber and other inhalation channels. However, the one-way valve is located on the main structure of the respiratory filter device. During exhalation, exhaled air inevitably reaches parts of the main structure above the one-way valve, such as the mouthpiece 17 and moistening paper 10, which are shared by the inhalation and exhalation paths. Exhaled air passes through these shared areas, and any contaminants in the exhaled air may remain in these shared areas. Because the handheld respiratory filter device is used by multiple people, when the next person uses it, any remaining contaminants in the shared areas will enter the body with the next person's inhalation. Therefore, there is still a risk of cross-contamination when used by different people.

[0006] Breathalyzers, including the instrument and filter, are currently used by multiple individuals due to frequency and cost considerations. During testing, exhaled air must pass through the device and enter the instrument. For indicators like nitric oxide, the air must be inhaled through the filter before testing, creating a significant risk of cross-contamination. In recent years, respiratory infections have become increasingly common worldwide. Therefore, designing breathalyzers to prevent the risk of cross-contamination is crucial for their clinical safety. Summary of the Invention

[0007] In order to overcome the above-mentioned problems and defects in the prior art, the present invention provides a filtering device, a mouthpiece and a detection method for preventing cross-contamination, aiming to eliminate the risk of cross-contamination when the device is used by multiple people in actual applications.

[0008] One of the objectives of the present invention is a filtering device for exhalation detection, comprising a device body, the device body comprising a shell, an inhalation channel and an exhalation channel arranged in the shell, and the gas in the exhalation channel cannot enter the inhalation channel; one end of the device body comprises an air inlet, and the air inlet is in gas communication with the inhalation channel of the device body; a mouthpiece is detachably mounted on the other end of the device body, the mouthpiece comprising a shell, an inhalation channel and an exhalation channel arranged in the shell, after installation, the exhalation channel and the inhalation channel of the mouthpiece respectively correspond to the exhalation channel and the inhalation channel of the device body and are airtightly combined; a one-way valve is arranged on the inhalation channel of the mouthpiece, when inhaling, the one-way valve on the inhalation channel is opened to open the inhalation channel, and when exhaling, the one-way valve on the inhalation channel is closed to close the inhalation channel; and an exhalation channel opening and closing device is also included, when inhaling, the opening and closing device is closed, and the exhalation channel is in a closed state.

[0009] The one-way valve on the exhalation channel of the device body, the one-way valve on the exhalation channel of the mouthpiece, and the solenoid valve on the detection instrument connected to the filter device can all serve as opening and closing devices for the exhalation channel. During exhalation, the one-way valve opens and / or the solenoid valve opens to open the exhalation channel; during inhalation, the one-way valve closes and / or the solenoid valve closes to close the exhalation channel. Other structures that can open and close the airway also fall within the scope of the opening and closing devices described herein.

[0010] For example, a breath detection filter device that prevents cross-contamination includes a mouthpiece and a device body. The mouthpiece is for single-person use and can be detachably mounted on the device body, which can be used by multiple people. The mouthpiece consists of a shell and an exhalation channel and an inhalation channel disposed within the shell. The device body consists of a shell and an exhalation channel and an inhalation channel disposed within the shell, and the exhalation channel and the inhalation channel are independent of each other. When the mouthpiece is mounted on the device body, the exhalation channel and the inhalation channel of the mouthpiece correspond to the exhalation channel and the inhalation channel of the device body, respectively, and are airtightly connected. The inhalation channel of the mouthpiece contains at least one one-way valve. The one-way valve opens only during inhalation, allowing gas to be inhaled into the human body through the mouthpiece. During exhalation, the one-way valve closes, preventing exhaled gas from entering the inhalation channel of the device body through the mouthpiece, thereby preventing contamination of the inhalation channel of the device body used by multiple people.

[0011] According to the technical solution of the present invention, after the mouthpiece and the device body are installed, it can effectively and thoroughly ensure that there is no common space or interface between the exhalation path and the inhalation path of the device body, and the common space is only retained on the mouthpiece dedicated to a single person, thereby achieving the purpose of completely eliminating cross-contamination.

[0012] The one-way valve can be made of flexible plastic or silicone material in an umbrella, T-shaped, or snap-on configuration, and mounted on the mouthpiece or a partition within the device body. During exhalation and inhalation, the main body of the one-way valve is forced upward by the positive force of exhalation pressure or inhalation negative pressure, opening the passage. When no exhalation or inhalation is taking place, the one-way valve returns to its initial position, fitting into the air vents of the one-way valve mounting partition. When subjected to the reactive force of exhalation or inhalation, the main body of the one-way valve and the air vents fit more tightly, ensuring that gas can flow in only one direction.

[0013] One of the objectives of the present invention is to provide a mouthpiece comprising a housing, wherein an inhalation passage and an exhalation passage are disposed within the housing. A one-way valve is disposed in the inhalation passage. During inhalation, the one-way valve opens to open the inhalation passage, and during exhalation, the one-way valve closes to close the inhalation passage. The mouthpiece can be used in conjunction with a filter device for exhalation detection.

[0014] Depending on actual use, the mouthpiece can be designed as an oral mouthpiece or a mask. An oral mouthpiece requires the subject to hold the mouthpiece tightly in their mouth to prevent air leakage during the oral-exhalation test. For those who cannot hold the mouthpiece tightly in their mouth, a mask can be used, designed to fit tightly around the subject's mouth. For nasal-exhalation tests, the mask can be designed to cover both the mouth and nose.

[0015] A partition may be provided in the mouthpiece, and the inhalation channel and the exhalation channel are opened on the partition. In one embodiment, a one-way valve mounting portion is provided on the partition.

[0016] The inhalation channel of the mouthpiece can be a cylindrical, rectangular, or irregularly shaped channel of a certain length, or it can be an opening. The inhalation channel of the mouthpiece is provided with at least one one-way valve, and an air vent is provided below the one-way valve. When inhaling, the one-way valve opens upward, and gas can be inhaled into the human body through the air vent; when exhaling, the one-way valve fits tightly against the air vent and is in a closed state, and the exhaled gas will not enter the inhalation channel of the device body through the air vent. Multiple one-way valves can be provided, and preferably, the one-way valves should be designed to be symmetrically arranged. The size of the air vent should not be too large. Its setting can increase the pressure on the one-way valve during inhalation, ensuring the opening of the one-way valve, while also ensuring the airtightness of the one-way valve during exhalation.

[0017] The exhalation channel of the mouthpiece can be a cylindrical, rectangular, or irregularly shaped channel of a certain length, or it can be an opening. During inhalation, the exhalation channel can be closed by a one-way valve provided on the device body, or a valve provided on the exhalation path of the detection instrument (for example, in some embodiments, the exhalation path of the detection instrument is provided with a solenoid valve and a pressure sensor. The solenoid valve is normally closed and opens when the exhalation pressure is detected to start gas sampling. It closes after a sufficient sample collection time has elapsed). That is, the channel is closed, so gas does not enter the exhalation channel of the mouthpiece through the exhalation channel of the device body.

[0018] During inhalation, the expiratory channel of the device body is closed by a one-way valve or solenoid valve, forming a closed pipeline. Inhalation places the expiratory channel in a negative pressure state. However, because the expiratory channel is open and the negative pressure is not very high, the gas in the expiratory channel is not easily aspirated. For example, the expiratory channel is made of a material that is not easily deformed, and the internal space of the expiratory channel is usually only a few tens of milliliters (for example, the maximum volume of the expiratory channel in the embodiment is only about 30 mL). Moreover, depending on the location of the expiratory channel opening and closing device (such as the one-way valve or battery valve), the actual space that can be affected by the negative pressure is only a few milliliters. Therefore, the gas aspirated from the channel by negative pressure is only a milliliter or even a negligible amount of gas. In a more optimal solution, a filter membrane is provided on the mouthpiece. Even if a very small amount of gas is aspirated, the filter membrane can filter out bacteria and other substances in the gas. Therefore, the risk of cross-contamination is significantly reduced.

[0019] Preferably, the exhalation channel of the mouthpiece can be provided with a one-way valve with a vent above the one-way valve. During exhalation, the one-way valve opens, while during inhalation, the one-way valve closely abuts the vent, closing it. This solution ensures that no gas is inhaled into the exhalation channel of the mouthpiece during inhalation, eliminating the need to confirm that the device or detection instrument has closed the exhalation channel. Gas is only inhaled through the inhalation channel of the mouthpiece. The vent should not be too large. Its provision can increase the pressure on the one-way valve during exhalation, ensuring that the one-way valve is open, while also ensuring that the one-way valve remains airtight during inhalation.

[0020] When the subject inhales, the inhaled air inevitably contains dust and pathogens. Therefore, the mouthpiece's inhalation channel can be equipped with a filter material, such as bacterial filter cotton or polymer nonwoven fabric. When the subject exhales, the exhaled air inevitably contains particulate matter such as saliva, droplets, food debris, and even bacteria and viruses. Therefore, the mouthpiece's exhalation channel can be equipped with a filter material, such as bacterial filter cotton, polymer nonwoven fabric, absorbent paper, or a combination of these materials. The filter material can be placed separately in the mouthpiece's inhalation and exhalation channels. However, for process and cost considerations, it is preferred that the filter material be placed above both channels, i.e., closer to the body than the channels themselves. During exhalation, air passes through the filter material and then enters the mouthpiece's exhalation channel. During inhalation, air passes through the mouthpiece's inhalation channel, then through the filter material, and ultimately enters the body. Preferably, a layer of humidifying paper can be placed beneath the filter material to balance the heat and moisture in the exhaled air during exhalation. Because the mouthpiece is a single-person component, even if a common area exists between the filter material and the humidifying paper for both exhalation and inhalation, cross-contamination is not an issue. In one embodiment, the filter material and humidifying paper are placed on a partition support.

[0021] The device body consists of a housing and independent exhalation and inhalation channels disposed within the housing. The exhalation and inhalation channels of the device body should correspond to and closely mate with the exhalation and inhalation channels of the mouthpiece, respectively, ensuring airtightness when assembled. A variety of common design methods can be used to ensure airtightness at these joints, such as interference fits, gasket seals, O-ring seals, and threaded seals.

[0022] An air inlet is provided on the shell of the main body of the device, and air enters the inhalation channel from the air inlet during inhalation. A one-way valve may also be provided at the upper end of the inhalation channel, that is, a position closer to the mouthpiece. The one-way valve opens during inhalation and closes during exhalation, serving as a further barrier to prevent cross-contamination. A filter device is provided in the inhalation channel, and the channel design ensures that the airflow does not bypass the filter device and enter the downstream channel. The filter device may include a filter material for filtering the substance to be tested in the inhaled gas. For example, for the detection of exhaled nitric oxide (FeNO), the filter material may be potassium permanganate particles, activated carbon, molecular sieves, or the like, or a mixture of these materials. The filter device may be designed in the form of bacterial filter cotton or polymer non-woven fabric wrapped around the filter material to avoid leakage of the filter material.

[0023] The exhalation channel of the device body can be equipped with a one-way valve that opens during exhalation and closes during inhalation. The one-way valve can be located anywhere in the exhalation channel, but preferably, it is located at the front end of the channel, near the connection with the mouthpiece exhalation channel, to minimize the risk of gas within the device body being inhaled into the human body during inhalation. The exhalation channel can be equipped with a filter material for filtering moisture, bacteria, and small particulate matter from the exhaled gas. The filter material can be a bacterial filter cotton, a desiccant, a molecular sieve, or a combination of these materials. The exhalation resistance can be adjusted by adjusting parameters such as the porosity and length of the filter material to meet the exhalation resistance requirements of the test. A connection device is provided at the end of the exhalation channel. Depending on the actual use situation, it can be designed to be directly or indirectly connected to the detection instrument. For the indirect connection embodiment, the connection device can be designed as a pipeline connector.

[0024] One of the objects of the present invention is also to provide a method for breath detection, comprising: providing a filtering device comprising a mouthpiece and a device body, wherein the mouthpiece is detachably connected to one end of the device body;

[0025] The device body includes a shell, an inhalation channel and an exhalation channel arranged in the shell; the other end of the device body includes an air inlet, and the air inlet is in gas communication with the inhalation channel of the device body;

[0026] The mouthpiece includes a housing, an inhalation channel and an exhalation channel are provided in the housing, and a one-way valve is provided on the inhalation channel. When inhaling, the one-way valve on the inhalation channel opens to open the inhalation channel, and when exhaling, the one-way valve on the inhalation channel closes to close the inhalation channel;

[0027] After the mouthpiece is installed on one end of the device body, the exhalation channel and the inhalation channel of the mouthpiece correspond to the exhalation channel and the inhalation channel of the device body respectively and are airtightly combined;

[0028] The filter device also includes an exhalation channel opening and closing device, which closes the exhalation channel during inhalation.

[0029] Providing a detection instrument that can be communicated with the exhalation channel of the device body;

[0030] When the subject inhales, the one-way valve on the inhalation channel of the mouthpiece opens and the opening and closing device on the exhalation channel closes, and the outside air enters from the air inlet of the device body, and enters the inhalation channel of the mouthpiece through the inhalation channel of the device body, and is finally inhaled into the human body; when the subject exhales, the opening and closing device on the exhalation channel opens and the one-way valve on the inhalation channel of the mouthpiece closes, and the exhaled gas enters the exhalation channel of the device body through the exhalation channel of the mouthpiece, and the exhaled gas is transported to the detection instrument.

[0031] Preferably, the gas in the exhalation channel of the device body cannot enter the inhalation channel.

[0032] The mouthpiece in the filtering device described in the present invention is for single-person use, which can avoid contamination of the inhalation channel of the device body used by multiple people, so as to achieve the purpose of preventing cross-contamination during the breath detection process. It can be used to detect the content of nitric oxide, carbon monoxide, exhaled hydrogen or methane in exhaled breath, and is very suitable for clinical promotion and application.

[0033] Currently, breathalyzers are trending towards smaller, more portable designs. The technical solutions of the present invention can also be applied to integrated designs of breath filtration devices and testing instruments. The filter device may be modified in various ways, such as using part of the testing instrument's housing as the filter device's housing, or embedding the filter device within the testing instrument. Similar designs fall within the spirit of the present invention and are intended to be protected within its scope. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a cross-sectional view of the breath detection filter device described in Example 1.

[0035] Figure 2 This is a cross-sectional view of the breath detection filter device described in Example 2.

[0036] Figure 3 This is a cross-sectional view of the mouthpiece component of the breath detection filter device described in Example 3.

[0037] Figure 4a 2. It is a cross-sectional view of the mouthpiece component of the breath detection filter device described in Example 1 and Example 2.

[0038] Figure 4b This is a top view of the one-way valve portion of the mouthpiece component of the breath detection filter device described in Example 1 and Example 2.

[0039] Figure 4c This is a structural diagram of the mouthpiece of Example 1 in which the inhalation channel is not equipped with a one-way valve.

[0040] Figure 5 This is a cross-sectional view of the mouthpiece component of the breath detection filter device described in Example 4.

[0041] Figure 6 A schematic diagram of the mouthpiece and device body after disassembly.

[0042] Figure 7 A schematic diagram of the mouthpiece and device body combination.

[0043] Figure 8a Schematic diagram of the one-way valve on the inhalation channel opening during inhalation.

[0044] Figure 8b Schematic diagram of the closed state of the one-way valve on the inhalation channel during exhalation.

[0045] Figure 9a Schematic diagram of the closed state of the one-way valve on the exhalation channel during inhalation.

[0046] Figure 9b Schematic diagram of the one-way valve on the exhalation channel opening during exhalation. DETAILED DESCRIPTION

[0047] Example 1

[0048] like Figure 1 、 Figure 6 and Figure 7 The device, shown here, provides an anti-cross-contamination breathalyzer filter. It includes a mouthpiece 100 and a device body 200. The mouthpiece is detachably connected to the device body. For example, in one design, the mouthpiece 100 is replaceable and dedicated to a single user, while the device body 200 can be used by multiple users.

[0049] The mouthpiece 100 comprises a housing 101, which includes an inhalation channel 110 and an exhalation channel 120. A one-way valve 111 is provided on the inhalation channel 110. The one-way valve 111 can be designed as a diaphragm, which opens when inhaling to open the inhalation channel and closes when exhaling to close the inhalation channel.

[0050] like Figure 1 、 Figure 4a 、 Figure 4b 、 Figure 4c 、 Figure 6 and 7 The mouthpiece 100 shown is a face mask. The housing 101 includes a face mask 102 and an outer gas passageway wall 103. The face mask includes a vent 104. The outer gas passageway wall 103 encloses an inhalation passage 110 and an exhalation passage 120. The face mask and the outer gas passageway wall are integrally formed or airtightly assembled together. Inhaled air enters the body through the inhalation passage and the mask vent, while exhaled air enters the exhalation passage through the mask vent.

[0051] like Figure 4a 、 Figure 4b and Figure 4c As shown, the mouthpiece 100 of this embodiment is provided with an inhalation channel 110 and an exhalation channel 120. A partition 105 is provided inside the outer wall of the gas channel. One end of the partition is connected to the outer wall, and the other end is connected to the wall of the exhalation channel 120. In this embodiment, the exhalation channel is provided in the middle of the mouthpiece. The cavity between the wall of the exhalation channel and the outer wall of the gas channel forms the inhalation channel 110. A one-way valve 111 is provided above the inhalation channel. Figure 8a As shown in the figure, when inhaling, the one-way valve on the inhalation channel opens to open the inhalation channel, and the inhaled gas enters the subject through the inhalation channel. Figure 8b As shown, during exhalation, the one-way valve is closed to close the inhalation channel, and the gas exhaled by the subject cannot enter the inhalation channel through the one-way valve of the inhalation channel.

[0052] In this embodiment, a vent hole 112 for the intake passage is provided on the partition 105. The vent hole 112 is located above the intake path of the one-way valve 111 of the intake passage 110. Providing the vent hole can increase the pressure exerted by the gas in the intake passage on the one-way valve during inhalation, thereby ensuring that the one-way valve is open. The vent hole should also be appropriately sized to avoid compromising the tightness of the one-way valve when closed. For example, the vent hole should be smaller than the one-way valve diaphragm so that the one-way valve diaphragm can completely cover the vent hole when the one-way valve is closed.

[0053] The partition is provided with a mounting socket 114 for a one-way valve 111. A pin 113 of the one-way valve is inserted into this socket 114. The diaphragm of the one-way valve 111 covers the inhalation passage. In this embodiment, the diaphragm of the one-way valve 111 covers the vent hole 112. The pin 113 of the one-way valve is inserted into the mounting socket 114 on the partition. The pin 113 and the socket 114 have an interference fit. The compression deformation of the one-way valve material ensures that the pin is inserted into the socket, forming an airtight connection.

[0054] A filter material 131 is provided above the inhalation channel 110 and the exhalation channel 120, for example, a filter material is provided between the inhalation channel, the exhalation channel and the mouthpiece vent. The filter material is mounted on the baffle bracket of the mouthpiece and is located above the inhalation airway and / or the vent. In a preferred embodiment, the filter material 131 is mounted on a filter material bracket 106, one end of which is connected to the baffle and the other end supports the filter material. There is a certain distance between the filter material and the diaphragm of the one-way valve to provide space for the one-way valve to open and close, thereby ensuring smooth airflow. The filter material can be bacterial filter cotton, non-woven fabric of polymer material, absorbent paper, etc., or a combination of these materials, to filter saliva, food residues, droplets, moisture, bacteria and viruses in exhaled air, and also to filter possible dust and bacteria in the inhaled air.

[0055] In one design, a partition is installed within the mouthpiece. The partition includes an exhalation channel of a certain length and an inhalation channel opening formed in the partition. The exhalation channel is located at the center of the partition, and the inhalation channel is formed between the exhalation channel tube wall and the inner wall of the mouthpiece shell. The partition can be removably placed within the mouthpiece or integrally formed with the mouthpiece.

[0056] The device body 200 includes a housing 201 and an inhalation channel 210 and an exhalation channel 220 disposed within the housing. Gas within the exhalation channel cannot enter the inhalation channel; for example, the exhalation channel and the inhalation channel are independent of each other. When the mouthpiece is assembled to the device body, the exhalation channel 120 and the inhalation channel 110 of the mouthpiece 100 correspond to and are airtightly connected to the exhalation channel 220 and the inhalation channel 210 of the device body 200, respectively. This airtight connection means that the connection between the two exhalation channels or the connection between the two inhalation channels is leak-proof after assembly. The housing of the device body 200 is provided with an air inlet 219, through which air enters the inhalation channel 210 during inhalation. A connection device 229 is provided at the end of the exhalation channel 220 (i.e., the end away from the mouthpiece). This connection device can be connected directly to a test instrument or via an air tube 300, thereby connecting the exhalation test filter device to the test instrument.

[0057] like Figure 1 and Figure 2 The device body 200 shown is provided with an inhalation channel 210 and an exhalation channel 220. A partition 205 is provided within the housing. The partition can be installed later and connected to the inner wall of the housing and the wall of the exhalation channel 220 via snaps. In this embodiment, the exhalation channel is located in the middle of the device body, and the cavity between the wall of the exhalation channel and the inner wall of the housing forms the inhalation channel 110.

[0058] exist Figure 1The upper end of the inhalation channel 210 shown in the example, that is, the end away from the air inlet 219, is provided with a one-way valve 211, which opens when inhaling and closes when exhaling. The provision of this one-way valve can further avoid cross-contamination in breath detection. At the same time, it can also allow the subject to use a mouthpiece of the existing technology (for example, there is no separate inhalation channel and exhalation channel in the mouthpiece) when the risk of cross-contamination is not high (such as when the device is used by a dedicated individual, or when different people using it are clearly healthy people), and cooperate with the main body of the device to reduce the cost of use. In one embodiment, a mounting socket for the one-way valve is provided on the partition, and the pin of the one-way valve is inserted into the socket, and the diaphragm of the one-way valve covers the inhalation channel. The pin is interference fit with the socket, and the compression deformation of the one-way valve material ensures that the pin is inserted into the socket to form an airtight connection.

[0059] A first chamber for storing a filter material 215 is provided in the inhalation channel 210. The first chamber is provided between two partitions of the inhalation channel, and the air flow will not enter the downstream channel (such as the inhalation channel of the mouthpiece) around the filter material 215. The filter material can be placed on the partition inside the shell. The filter material 215 can include a filter material for filtering the substance to be tested in the inhaled gas. For example, for detecting exhaled nitric oxide (FeNO), the filter material can be potassium permanganate particles, activated carbon, molecular sieves and other substances or a mixture of these materials. The filter material 215 can be in the form of bacterial filter cotton or polymer non-woven fabric wrapped filter material to avoid leakage of the filter material. If necessary, a second chamber 216 for storing the filter material can also be provided in the inhalation channel 210, and the two chambers are arranged in series on the inhalation channel. In this example, the filter material is provided below the one-way valve, that is, upstream of the one-way valve in the inhalation path.

[0060] A one-way valve 221 is provided at one end of the exhalation channel 220 close to the mouthpiece 100, which opens during exhalation and closes during inhalation, ensuring that the gas in the exhalation channel 220 in the device body 200 will not be inhaled into the human body during inhalation.

[0061] Filter material 225 is provided within the exhalation channel 220. This filter material can be a bacterial filter, desiccant, molecular sieve, or a combination of these materials. It is used to further filter moisture, bacteria, and small particulate matter from the exhaled gas, preventing contamination of the detection instrument by the exhaled gas and the formation of condensed water in the instrument's air path. The filter material can be placed on a support frame within the exhalation channel.

[0062] The filter material in the breath detection filter device will not move substantially within the housing during the breath test.

[0063] like Figure 1 and 7As shown, the head end of the device body (i.e., the end connected to the mouthpiece) is provided with a mounting socket 202, into which the outer tube wall 103 of the mouthpiece's gas channel or the pin is inserted, thereby connecting the mouthpiece to the device body. The inhalation channel on the mouthpiece and the inhalation channel on the device body form an air path. In this embodiment, the exhalation channel of the device body is inserted into the exhalation channel of the mouthpiece to achieve the connection between the two exhalation channels. In this example, the exhalation channel on the mouthpiece and the exhalation channel on the device body are connected to each other through an interference fit between the two, and the airtightness between the two is guaranteed.

[0064] Based on the above embodiment, when the first subject inhales, air enters from the air inlet 219 of the device body 200, and passes through the filter material and the one-way valve 211 in the inhalation channel 210 of the device body in sequence, then enters the inhalation channel 110 of the mouthpiece 100, and then passes through the one-way valve 111 on the inhalation channel 110 and the filter material 131 on the mouthpiece in sequence, and is finally inhaled into the human body. When the subject exhales, the exhaled gas passes through the filter material 131 on the mouthpiece and the exhalation channel 120 on the mouthpiece in sequence, enters the exhalation channel 220 of the device body, and then passes through the one-way valve 221 and the filter material 225 on the exhalation channel of the device body in sequence to reach the connecting device 229, and the exhaled gas sample is transported to the detection instrument through the trachea 300. For the direction of the airflow of inhalation and exhalation, see Figure 1 , the solid arrow line indicates the direction of the inspiratory airflow, and the dotted arrow line indicates the direction of the expiratory airflow.

[0065] When the first subject completes the breath test, the mouthpiece is removed from the device body. When the second subject needs to undergo a breath test, a new mouthpiece is installed on the device body. When the second subject inhales, external air enters the human body through the inhalation channel. Since a one-way valve is provided on the exhalation channel of the device body, and in particular, the one-way valve of the exhalation channel of the device body is provided at the opening of the exhalation channel, when the second subject inhales, even if there are remnants of the first subject's exhalation in the exhalation channel of the device body, these remnants will not enter the subject through the exhalation channel of the mouthpiece.

[0066] If the one-way valve of the exhalation channel of the device body is not installed at the opening of the exhalation channel of the device body, but is set at a position slightly below the opening, a small section of the channel that cannot be closed by the one-way valve is left between the one-way valve and the opening. Since this section of the channel is at the junction of the device body and the mouthpiece, the disinfectant is relatively easy to reach and can be thoroughly disinfected and cleaned. Therefore, after the first subject completes the breath test, the medical staff only needs to disinfect this small part of the exhalation channel with a disinfectant to complete the cleaning and disinfection of the device body, avoiding cross-contamination. Moreover, since the exhalation channel of the device body is closed by the one-way valve, the exhalation channel of the mouthpiece is in a negative pressure state when inhaling, so the gas in the channel is not easily sucked out or only a very small amount of gas can be sucked out. This greatly reduces the risk of cross-contamination.

[0067] Example 2

[0068] This embodiment Figure 2 As shown. Compared to Example 1, Example 2 has the same mouthpiece design as Example 1. The main difference is that Example 2 does not include a one-way valve 211 on the inhalation channel 210 of the device body 200. Because the one-way valve 111 is already installed on the inhalation channel 110 of the mouthpiece 100, the one-way valve 111 on the mouthpiece closes during exhalation, preventing exhaled gas from entering the mouthpiece's inhalation channel and, consequently, the inhalation channel 210 of the device body 200. This prevents exhaled gas from contaminating the inhalation channel of the device body, achieving the practical effect of preventing cross contamination.

[0069] Example 3

[0070] like Figure 3 The mouthpiece shown in Example 3 can be used with the device body 200 of Example 1 or Example 2. In the mouthpiece design of this embodiment, a one-way valve 121 is added to the exhalation channel 120 of the mouthpiece. In a preferred embodiment, a vent 122 is provided above the one-way valve in the exhalation path. One-way valves 121 and 111 are provided on both the exhalation channel 120 and the inhalation channel 110 of the mouthpiece, further ensuring that exhaled gas does not contaminate the inhalation channel of the device body. During inhalation, gas is not inhaled from the path of the exhalation channel, completely eliminating the risk of cross-contamination. The mouthpiece can be used in devices for exhalation and inhalation detection.

[0071] like Figure 9a As shown in the figure, when inhaling, the one-way valve on the exhalation channel is closed to close the exhalation channel, and the gas in the exhalation channel cannot enter the subject. Figure 9b As shown, during exhalation, the one-way valve opens to open the exhalation channel, and the gas exhaled by the subject enters the exhalation channel through the one-way valve of the exhalation channel.

[0072] Example 4

[0073] like Figure 5 The illustrated mouthpiece features a layer of humidifying paper 132 beneath the filter material 131 of the mouthpiece 100. This humidifying paper balances the heat and moisture content of exhaled air, preventing the exhaled air from entering the exhalation passage 220 of the device body 200, accelerating the depletion of the filter material 225, or forming condensation in the exhalation passage 200 or even within the detection instrument. This embodiment of the mouthpiece can be used with the device body described in Example 1 or Example 2.

[0074] After ensuring that the device body and the mouthpiece are assembled together, the exhalation channel and inhalation channel of the device body correspond to the exhalation channel and inhalation channel of the mouthpiece respectively and cooperate with each other in an airtight manner. The arrangement of the inhalation channel and the exhalation channel in the mouthpiece or the device body can be designed arbitrarily according to needs. For example, the exhalation channel is set in the middle of the mouthpiece or the device body, and the inhalation channel surrounds the outer periphery of the exhalation channel. For another example, the inhalation channel and the exhalation channel are set in two independent areas of the mouthpiece or the device body, for example, the inhalation channel and the exhalation channel are arranged side by side on the left and right.

[0075] There can be one or more exhalation channels on the mouthpiece and the device body, and there can be one or more inhalation channels on the mouthpiece and the device body.

[0076] The exhalation channel and the inhalation channel of the mouthpiece can be cylindrical, rectangular or irregularly shaped channels with a certain length, or can be an opening or a vent.

[0077] Verified analysis shows that the filter device of the present invention has good anti-cross infection performance in breath detection.

Claims

1. A filter device for breath detection, comprising a device body and a mouthpiece, wherein the device body comprises a housing, an inhalation channel and an exhalation channel disposed within the housing, wherein gas in the exhalation channel cannot enter the inhalation channel; one end of the device body comprises an air inlet, the air inlet being in gas communication with the inhalation channel of the device body; characterized in that: The mouthpiece is detachably mounted on the other end of the device body, and the mouthpiece includes a shell, in which an inhalation channel and an exhalation channel are provided. After installation, the exhalation channel and the inhalation channel of the mouthpiece correspond to the exhalation channel and the inhalation channel of the device body respectively and are airtightly combined; a one-way valve is provided on the inhalation channel of the mouthpiece, and when inhaling, the one-way valve on the inhalation channel opens to open the inhalation channel, and when exhaling, the one-way valve on the inhalation channel closes to close the inhalation channel; it also includes an exhalation channel opening and closing device, and when inhaling, the opening and closing device is closed, and the exhalation channel is in a closed state, and the opening and closing device is provided on the exhalation channel of the mouthpiece or at the front end of the exhalation channel of the device body, that is, at the connection with the mouthpiece; the mouthpiece is dedicated to one person, and the device body can be used by multiple people.

2. The filtering device according to claim 1, characterized in that The opening and closing device of the exhalation channel is selected from one or a combination of the following: a one-way valve on the exhalation channel of the device body, a one-way valve on the exhalation channel of the mouthpiece, and an electromagnetic valve on the detection instrument connected to the filtering device; when exhaling, the one-way valve opens and / or the electromagnetic valve opens to open the exhalation channel; when inhaling, the one-way valve closes and / or the electromagnetic valve closes to close the exhalation channel.

3. The filtering device according to claim 1, characterized in that The airtight connection method is selected from self-tightening interference fit, gasket sealing, O-ring sealing, and thread sealing.

4. The filtering device according to any one of claims 1 to 3, characterized in that The air intake passage of the device body includes a filter material.

5. A mouthpiece, comprising a shell, characterized in that: An inhalation channel and an exhalation channel are provided in the shell, and a one-way valve is provided on the inhalation channel. When inhaling, the one-way valve on the inhalation channel opens to open the inhalation channel, and when exhaling, the one-way valve on the inhalation channel closes to close the inhalation channel; when the mouthpiece is assembled to the main body of the breath detection device, the exhalation channel and the inhalation channel of the mouthpiece respectively correspond to the exhalation channel and the inhalation channel of the main body of the device and are airtightly combined. The mouthpiece is for single person only, and the main body of the device can be used by multiple people.

6. The mouthpiece according to claim 5, characterized in that The exhalation channel of the mouthpiece is provided with a one-way valve. When exhaling, the one-way valve on the exhalation channel opens to open the exhalation channel. When inhaling, the one-way valve on the exhalation channel closes to close the exhalation channel.

7. The mouthpiece according to any one of claims 5 to 6, characterized in that A filter material layer is provided inside the mouthpiece.

8. A method for breath detection, comprising: Provided is a filtering device comprising a mouthpiece and a device body, wherein the mouthpiece is detachably connected to one end of the device body; The mouthpiece is for single use only, while the main body of the device can be used by multiple people; The device body includes a housing, an inhalation channel and an exhalation channel provided in the housing, wherein the gas in the exhalation channel cannot enter the inhalation channel; the other end of the device body includes an air inlet, which is in gas communication with the inhalation channel of the device body; The mouthpiece includes a housing, an inhalation channel and an exhalation channel are provided in the housing, and a one-way valve is provided on the inhalation channel. When inhaling, the one-way valve on the inhalation channel opens to open the inhalation channel, and when exhaling, the one-way valve on the inhalation channel closes to close the inhalation channel; After the mouthpiece is installed on one end of the device body, the exhalation channel and the inhalation channel of the mouthpiece correspond to the exhalation channel and the inhalation channel of the device body respectively and are airtightly combined; The filter device also includes an exhalation channel opening and closing device, which closes the exhalation channel during inhalation. The opening and closing device is arranged on the exhalation channel of the mouthpiece or at the front end of the exhalation channel of the device body, i.e., at the connection with the mouthpiece. Providing a detection instrument that can be communicated with the exhalation channel of the device body; When the subject inhales, the one-way valve on the inhalation channel of the mouthpiece opens and the opening and closing device on the exhalation channel closes, and the outside air enters from the air inlet of the device body, and enters the inhalation channel of the mouthpiece through the inhalation channel of the device body, and is finally inhaled into the human body; when the subject exhales, the opening and closing device on the exhalation channel opens and the one-way valve on the inhalation channel of the mouthpiece closes, and the exhaled gas enters the exhalation channel of the device body through the exhalation channel of the mouthpiece, and the exhaled gas is transported to the detection instrument.

9. According to the method of claim 8, the opening and closing device on the exhalation channel is selected from one or a combination of the following: a one-way valve on the exhalation channel of the device main body, a one-way valve on the exhalation channel of the mouthpiece, and an electromagnetic valve on the detection instrument connected to the filtering device; when exhaling, the one-way valve opens and / or the electromagnetic valve opens to open the exhalation channel; when inhaling, the one-way valve closes and / or the electromagnetic valve closes to close the exhalation channel.

10. The method according to any one of claims 8 to 9, characterized in that Used to detect the content of nitric oxide, carbon monoxide, exhaled hydrogen or methane in exhaled breath.

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