Breathing filter box with resistance self-detection function and protective mask

Abstract

The invention provides a breathing filter box with a resistance self-detection function and a protective mask, the breathing filter box with the resistance self-detection function comprises a shell, and filter cotton is detachably arranged in the shell; the airtight elastic membrane is located in the shell, the airtight elastic membrane and the filter cotton jointly divide a cavity of the shell into two parts, respiratory airflow resistance in the shell can form pressure difference on the two sides of the filter cotton, and the airtight elastic membrane can elastically deform in a concave-convex mode along with the pressure difference; the transparent pane is located on the surface of the shell; wherein a first coating is arranged on the face, facing the airtight elastic membrane, of the transparent pane, a second coating is arranged on the face, facing the transparent pane, of the airtight elastic membrane, and color changing or developing can occur after the first coating and the second coating make contact with each other. In this way, a user can know the breathing resistance condition in the breathing filter box through visual feedback, and therefore the filter cotton can be replaced in time when the service life of the filter cotton is up.

Description

Technical Field

[0001] The present application relates to the field of personal protective equipment, and particularly to a breathing filter cartridge with self-detection of resistance and a protective mask. Background Art

[0002] With the upgrading and transformation of the manufacturing industry and the development of the intelligent manufacturing industry, the labor safety protection of front-line production personnel has received increasing attention. Among them, the face mask respirator, as an effective respiratory protection device, is widely used in front-line production and health and epidemic prevention. In industrial fields with severe dust pollution represented by mines, after the filter material of the filter cartridge on the ordinary protective face mask is used for a period of time, it will adsorb a large amount of particulate matter, which will increase the breathing resistance and deteriorate the filtering effect. At this time, it is necessary to replace the new filter cotton in time.

[0003] There are five common filter cotton materials, including gauze, activated carbon, non-woven fabric, glass fiber, and electrostatic filter cotton. In actual use, users often decide whether to replace the filter cotton based on their own experience, lacking an objective judgment standard. The over-life use of the filter cotton in the filter cartridge of the protective face mask will fail to provide protection for the wearer and damage the respiratory system of the wearer. If the filter cotton is replaced prematurely, the filter cotton is not fully utilized, which is also a waste.

[0004] Therefore, it is necessary to help the wearer accurately calculate the service life of the filter cotton.

[0005] The Chinese utility model with the publication number "CN214912797U" discloses an "intelligent protective face mask with a filter cartridge replacement prompt device". A service life prompt device is provided on the filter cartridge of this utility model, and the service life prompt device is connected to a power supply and a timing module. This timing module is a simple countdown record and has no association with the actual number of breaths and breathing intensity of the filter cotton.

[0006] The Chinese utility model with the publication number "CN211962840U" discloses a "timing device for a head-mounted device and a face mask respirator". The timer of this utility model includes a solar panel. After the relevant working parameters are set, the timer will start timing when each limit switch is closed and accumulate and save the timing result. Although this timing can be paused and accumulated, its judgment of the service life of the filter cotton is still an indirect judgment. And it requires the circuit system to supply power to the timer, with a relatively high overall cost. Summary of the Invention

[0007] In view of the state of the above-mentioned prior art, the present application is made. In a first aspect, the purpose of the present application is to provide a breathing filter cartridge with self-detection of resistance.

[0008] The technical solution adopted in this application includes: a housing, inside which a filter cotton is detachably arranged; an airtight elastic diaphragm, which is located inside the housing. The airtight elastic diaphragm and the filter cotton divide the cavity of the housing into two parts. The breathing air flow resistance inside the housing can form a pressure difference on both sides of the filter cotton, and the airtight elastic diaphragm can elastically deform in a concave-convex shape along with the pressure difference; a transparent window pane, which is located on the surface of the housing; wherein, a first coating is arranged on the side of the transparent window pane facing the airtight elastic diaphragm, and a second coating is arranged on the side of the airtight elastic diaphragm facing the transparent window pane. After the first coating and the second coating come into contact with each other, they can change color or develop color.

[0009] As a further improvement of this application, a colored circular line group including several concentric circles is arranged on the transparent window pane. The color of the colored circular line group becomes lighter towards the outside along the radial direction; the outlines of the first coating and the second coating are both circular.

[0010] As a further improvement of this application, the first coating and the second coating can undergo an irreversible chemical color development reaction after coming into contact with each other under the action of breathing water vapor.

[0011] As a further improvement of this application, the first coating and the second coating are each optionally a ferric chloride coating or a potassium ferrocyanide coating, and the materials of the first coating and the second coating are different from each other.

[0012] As a further improvement of this application, the housing includes an outer half-shell and an inner half-shell that are assembled in a detachable manner. An air-permeable seam is formed between the outer half-shell and the inner half-shell. The inner half-shell has an air flow interface for breathing air flow to pass through; the transparent window pane is assembled with the outer half-shell in a detachable and airtight manner, and the airtight elastic diaphragm is detachably assembled on the inner half-shell.

[0013] As a further improvement of this application, the air flow interface, the first coating, and the second coating are coaxially arranged.

[0014] As a further improvement of this application, the outer half-shell has a first main opening, and the inner half-shell has a second main opening. The opening area of the second main opening is smaller than the opening area of the first main opening. The filter cotton and the airtight elastic diaphragm jointly cover the second main opening; the covering area of the filter cotton on the second main opening is larger than the covering area of the airtight elastic diaphragm on the second main opening; one cavity of the housing is located on one side of the second main opening, and the other cavity of the housing is located on the other side of the filter cotton and the airtight elastic diaphragm away from the one side. The air flow interface is located in the other cavity.

[0015] As a further improvement of the present application, the airtight elastic diaphragm includes a strip plate. The two ends of the strip plate in the length direction are detachably assembled with the inner half shell. The middle part of the strip plate has a circular elastic membrane area. The flexibility of the elastic membrane area is greater than that of other positions of the strip plate. The second coating is located in the elastic membrane area.

[0016] As a further improvement of the present application, the outer half shell includes a base plate and an enclosing plate arranged around the edge of the base plate. The base plate of the outer half shell has a through window hole. One edge of the window hole intersects with the enclosing plate. The transparent pane is assembled with the window hole. The edge of the window hole has a three-sided groove structure, and the three-sided groove structure includes a T-shaped groove. The edge of the transparent pane has a T-shaped rib that is hermetically and movably assembled with the T-shaped groove.

[0017] In a second aspect, a protective mask is provided, which includes the above-mentioned breathing filter cartridge with self-detection of resistance.

[0018] The beneficial effects of the breathing filter cartridge with self-detection of resistance in the present application include:

[0019] First, it avoids the disadvantages of the traditional method of using human perception to judge the use situation of the breathing filter cartridge, establishes a unified objective judgment standard, eliminates the influence of individual differences on the judgment of the filter cotton replacement time, and can significantly improve the reliability of the detection results. The principle is to utilize the pressure difference formed on both sides of the filter cotton by the breathing airflow resistance in the breathing filter cartridge. When the filter cotton is closer to its own service life, its breathing resistance will be greater, which will cause the pressure difference on both sides of the filter cotton to become larger, making the airtight elastic diaphragm undergo more and more obvious elastic concave and convex deformations with the pressure difference. Furthermore, it causes the second coating on the airtight elastic diaphragm and the first coating on the transparent pane to come into contact with each other and can change color or develop color with the assistance of the breathing water vapor of the user, converting the change in breathing resistance into a visual color change, avoiding the subjective judgment error caused by individual differences, and enabling the user to accurately judge the use state of the breathing filter cartridge based on the color change. This design judges the service life of the filter cotton based on the actual breathing frequency, breathing time, and breathing intensity, rather than simply inferring the service life of the filter cotton based on external timing, so the accuracy is higher.

[0020] Secondly, without using electronic devices, it realizes the judgment and measurement of breathing resistance only based on the pressure difference and the two coating materials. The principle is simple and easy to implement. This design does not require power supply, reduces the production cost, and enables it to be applicable to special environments such as mines with explosion-proof safety requirements, broadening the application scenarios.

[0021] Finally, the transparent pane is provided so that the change in color can be observed by the user from the outside. The user can timely understand the breathing resistance inside the breathing filter cartridge through intuitive visual feedback, so as to replace the filter cotton in time when the filter cotton reaches the service life, effectively avoiding the failure of the filter cotton caused by overuse of the filter cotton, reducing the harm caused by the failed filter cotton to the human body, and improving the safety and reliability of respiratory protection. Brief Description of the Drawings

[0022] In order to more clearly illustrate the technical solutions in the embodiments, the drawings of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0023] Figure 1 is a schematic structural diagram of an embodiment of the breathing filter cartridge with self-detection of resistance of the present application;

[0024] Figure 2 is a schematic structural diagram of an embodiment of the breathing filter cartridge with self-detection of resistance of the present application;

[0025] Figure 3 is a schematic structural diagram of the outer half shell of an embodiment of the breathing filter cartridge with self-detection of resistance of the present application;

[0026] Figure 4 is a schematic structural diagram of the inner half shell of an embodiment of the breathing filter cartridge with self-detection of resistance of the present application;

[0027] Figure 5 is an exploded view of an embodiment of the breathing filter cartridge with self-detection of resistance of the present application;

[0028] Figure 6 is a perspective view of an embodiment of the breathing filter cartridge with self-detection of resistance of the present application;

[0029] Figure 7 is a perspective view of an embodiment of the breathing filter cartridge with self-detection of resistance of the present application;

[0030] Figure 8 is a front view of an embodiment of the breathing filter cartridge with self-detection of resistance of the present application;

[0031] Figure 9 is Figure 8 the A-A cross-sectional view of

[0032] Figure 10 is an assembly drawing of the inner half shell and the filter cotton of an embodiment of the breathing filter cartridge with self-detection of resistance of the present application;

[0033] Figure 11 Is a perspective view of an airtight elastic diaphragm of an embodiment of the breathing filter cartridge with self - resistance detection of the present application;

[0034] Figure 12 Is a perspective view of an airtight elastic diaphragm of an embodiment of the breathing filter cartridge with self - resistance detection of the present application;

[0035] Figure 13 Is an assembly drawing of an inner half - shell, filter cotton, and airtight elastic diaphragm of an embodiment of the breathing filter cartridge with self - resistance detection of the present application;

[0036] Figure 14 Is a perspective view of a transparent pane of an embodiment of the breathing filter cartridge with self - resistance detection of the present application;

[0037] Figure 15 Is an installation schematic diagram of a transparent pane of an embodiment of the breathing filter cartridge with self - resistance detection of the present application;

[0038] Figure 16 Is Figure 15 A partial enlarged view of point B of;

[0039] Figure 17 Is an application schematic diagram of an embodiment of the protective mask of the present application;

[0040] Figure 18 Is a color - display schematic diagram of an embodiment of the breathing filter cartridge with self - resistance detection of the present application;

[0041] Figure 18 (a) of is the first stage of the color - display schematic diagram of an embodiment of the breathing filter cartridge with self - resistance detection of the present application;

[0042] Figure 18 (b) of is the second stage of the color - display schematic diagram of an embodiment of the breathing filter cartridge with self - resistance detection of the present application;

[0043] Figure 18 (c) of is the third stage of the color - display schematic diagram of an embodiment of the breathing filter cartridge with self - resistance detection of the present application;

[0044] Figure 18 (d) of is the fourth stage of the color - display schematic diagram of an embodiment of the breathing filter cartridge with self - resistance detection of the present application.

[0045] Explanation of reference numerals

[0046] 1 - Outer half shell; 101 - First main opening; 102 - Window hole; 103 - First snap part; 104 - T-shaped groove; 105 - End groove; 106 - Rib plate; 2 - Transparent pane; 201 - T-shaped ridge; 202 - Holding part; 203 - Chamfer; 3 - First coating; 4 - Filter cotton; 5 - Air-impermeable elastic diaphragm; 501 - Strip plate; 502 - Male buckle; 503 - Elastic membrane area; 6 - Second coating; 7 - Colored round wire group; 701 - Single round wire; 8 - Colored round pattern; 9 - Inner half shell; 901 - Second main opening; 9011 - First hole; 9012 - Second hole; 902 - Airflow interface; 903 - Second snap part; 904 - Female buckle; 905 - Partition rib; 906 - Sinking pipe; 10 - Air-permeable seam; 1091 - Base plate; 1092 - Enclosing plate; 11 - Silicone mask cover Detailed implementation manners

[0047] The exemplary implementation manners of the present application will be described below with reference to the accompanying drawings. It should be understood that these specific descriptions are only used to teach those skilled in the art how to implement the present application, rather than to exhaust all feasible ways of the present application, nor to limit the scope of the present application.

[0048] Refer to Figure 5 , the implementation manner of the present application provides a breathing filter cartridge with self-detection of resistance. The breathing filter cartridge includes a housing, an air-impermeable elastic diaphragm 5, and a transparent pane 2. Among them, the housing can be a detachable housing, and a replaceable filter cotton 4 is arranged inside the housing. The air-impermeable elastic diaphragm 5 is located inside the housing. The air-impermeable elastic diaphragm 5 and the filter cotton 4 can be arranged side by side and divide the cavity of the housing into two parts together ( Figure 1 schematically shows the upper and lower two cavities, Figure 9 a specific example of the two cavities is given in), when using the breathing filter cartridge of the present application, the breathing airflow will pass through the filter cotton 4. The resistance of the breathing airflow inside the housing can form a pressure difference on both sides of the filter cotton 4, and the air-impermeable elastic diaphragm 5 can undergo elastic concave and convex deformation along with the pressure difference. The transparent pane 2 is located on the surface of the housing. A first coating 3 is arranged on the surface of the transparent pane 2 facing the air-impermeable elastic diaphragm 5 (refer to Figure 14 ), and a second coating 6 is arranged on the surface of the air-impermeable elastic diaphragm 5 facing the transparent pane 2 (it can also be referred to Figure 11 ), and the first coating 3 and the second coating 6 can change color or show color after coming into contact with each other. The color change can be a physical color change after mixing two different color pigments, and the color development can be a chemical color development after contact of two chemical substances.

[0049] Through the combined design of the housing, the filter cotton 4, the airtight elastic diaphragm 5 and the transparent pane 2, the pressure difference formed on both sides of the filter cotton 4 by the air flow during breathing is used to drive the deformation of the airtight elastic diaphragm 5. This deformation is generally reciprocating concave and convex and elastic. Therefore, the spatial position of the second coating 6 will also change reciprocally. When the spatial position of the second coating 6 moves to a certain extent, it will trigger the contact between the first coating 3 on the transparent pane 2 and the second coating 6 on the airtight elastic diaphragm 5 and cause a color reaction. The visualization detection of the life of the filter cotton 4 is realized without the aid of external electronic devices. The color result can intuitively display the actual life state of the filter cotton 4. It avoids the problem that the traditional breathing filter box relies on the subjective feeling of the human body to judge the replacement time, and is convenient to establish an objective judgment standard based on color change. Also, because it does not rely on external electronic devices, it does not require power supply, reduces the manufacturing cost, meets the requirements of explosion-proof environment, is technically reliable, and can significantly reduce the overall production cost of the breathing filter box.

[0050] As Figure 5 , Figure 14 shown, in an embodiment, a colored circular line group 7 including a plurality of concentric circles is arranged on the transparent pane 2. The colored circular line group 7 is composed of a plurality of concentric single circular lines 701. Figure 14 The dotted lines in Figure 18 represent each single circular line 701. There is no filled color between adjacent single circular lines 701. And the color of the colored circular line group 7 becomes lighter towards the outside along the radial direction (see Figure 18 ). That is, the diameters of different single circular lines 701 are different from each other, and the larger the diameter of the single circular line 701, the lighter its color. The outlines of the first coating 3 and the second coating 6 can both be circular.

[0051] The beneficial effect of adopting the above embodiment is that: a concentric colored circular line group 7 with a gradually lighter color from the inside to the outside is set on the transparent pane 2. Combining with the circular outline of the second coating 6, through the colored circular pattern 8 (see Figure 18)The degree of coverage of the single circular line 701 is used to quantify the breathing resistance. Since the closer the filter cotton 4 is to the service life limit, the worse its air permeability and the greater the breathing resistance. That is, as the amount of particles attached to the filter cotton 4 increases, the air permeability decreases, the pressure drop inside and outside gradually increases, and tends to be constant after reaching a certain critical value. Since there is a fixed functional relationship between the pressure drop inside and outside the filter cotton 4 and the amount of particles, it is feasible to judge the service life of the filter cotton 4 through the pressure difference inside and outside the filter cotton 4. The greater the pressure difference on both sides of the filter cotton 4, the more obvious the concave-convex deformation of the airtight elastic diaphragm 5, which will result in more contact pressure and a larger contact area between the first coating 3 and the second coating 6, and finally form a colored circular pattern 8 on the inner surface of the transparent pane 2. The color of the colored circular pattern 8 is generally darker in the center and lighter at the edge, and the overall contour is approximately circular. The colored circular pattern 8 is formed only after the first coating 3 and the second coating 6 come into contact and change color, and it does not exist originally. In addition, several concentric colored circular line groups 7 also provide multi-level life warnings to enhance the accuracy of visual judgment. Since the color of the circular ring group 7 is darker inside and lighter outside, when the colored circular pattern 8 covers one of the single circular lines 701, the single circular line 701 will be hidden due to the disappearance of the color contrast, indicating that a new filter cotton 4 needs to be replaced at this time. The user can quantitatively judge whether the current breathing resistance reaches the critical value by observing the degree of disappearance of the colored circular line group 7. Converting the breathing resistance into a visual color basis avoids subjective judgment errors and improves the self-checking accuracy.

[0052] In a non-limiting example, specifically, the colored circular line group 7 can be printed on the transparent pane 2, and can be printed on the outer side of the transparent pane 2, that is, the colored circular line group 7 and the first coating 3 are located on the front and back sides of the transparent pane 2 respectively.

[0053] In a non-limiting example, the transparent pane 2 is also made of an airtight material, and the transparent pane 2 remains airtight after being assembled with the housing. The design purpose of the transparent pane 2 is firstly to be transparent for easy color observation, and secondly to be a carrier for the first coating 3. As Figure 1 It can also be seen that, compared with the transparent pane 2, the airtight elastic diaphragm 5 has more obvious flexibility and elasticity. It can be understood that Figure 1 The wavy shape of the shown airtight elastic diaphragm 5 is only used to schematically show that the airtight elastic diaphragm 5 has flexibility and elasticity, and is not used to limit the shape of the airtight elastic diaphragm 5. For example, in one example, before use, the airtight elastic diaphragm 5 can be presented as a plane.

[0054] The color comparison principle of the colored circular pattern 8 and the colored circular line group 7 can refer to Figure 18 , Figure 18 The (a) in Figure 18 shows that the first coating 3 and the second coating 6 have not come into contact yet, so the colored circular pattern 8 has not been formed yet at this time. Figure 18(c) of Figure 18 (d) indicates that as the number of contacts between the first coating 3 and the second coating 6 increases or the contact area becomes larger, the color of the colored circular pattern 8 gradually darkens, and the diameter of the colored circular pattern 8 also gradually increases.

[0055] In a non-limiting example, the airtight elastic diaphragm 5 can be made of a polymer film, such as medical-grade silicone, which can be polydimethylsiloxane (PDMS), with a thickness range of 50 μm to 100 μm, and has the advantages of excellent flexibility and low cost.

[0056] In one embodiment, the first coating 3 and the second coating 6 can undergo an irreversible chemical color reaction after coming into contact with each other under the action of respiratory water vapor. Among them, Figure 5 、 Figure 11 、 Figure 13 、 Figure 14 、 Figure 15 The first coating 3 or the second coating 6 is represented by sand dot texture filling in all of them.

[0057] The beneficial effects of adopting the above embodiment are as follows: The color reaction selects a chemical reaction, and it is an irreversible color reaction, which makes the color reaction more prominent and reliable. The first coating 3 and the second coating 6 undergo an irreversible color reaction under the action of respiratory water vapor, making full use of the natural water vapor environment generated during breathing, and allowing the respiratory water vapor to provide the necessary conditions for the chemical reaction after the coatings come into contact. The presence of water vapor makes the chemical reaction between the coatings more likely to occur during use, reducing the possibility of failure of the first coating 3 and the second coating 6 during storage, turnover, etc.

[0058] In one embodiment, the adhesion of the first coating 3 on the transparent pane 2 is greater than the adhesion of the second coating 6 on the airtight elastic diaphragm 5, so as to ensure that the main coating mixing and color reaction occur on one side of the transparent pane 2, thus facilitating observation.

[0059] In one embodiment, the first coating 3 and the second coating 6 are two different chemical substances, that is, the first coating 3 and the second coating 6 need to meet the following conditions: First, they can adhere to the surface of plastic or polymer films; second, the first coating 3 and the second coating 6 are colorless or have a light color themselves; third, the first coating 3 and the second coating 6 will undergo a chemical reaction to produce color or change color after coming into contact; fourth, this color reaction is irreversible; fifth, the first coating 3 and the second coating 6 will not be negatively affected by the carbon dioxide and water vapor in breathing; sixth, the first coating 3 and the second coating 6 and their generated substances need to be non-toxic and will not damage the respiratory system of users; seventh, the self-cost of the first coating 3 and the second coating 6 is relatively low.

[0060] In one embodiment, the first coating 3 and the second coating 6 are each optionally an iron chloride coating or a potassium ferrocyanide coating, and the materials of the first coating 3 and the second coating 6 are different from each other. Specifically, the first coating 3 may be an iron chloride (FeCl3) coating, and the second coating 6 may be a potassium ferrocyanide (K4[Fe(CN)6]) coating. The iron chloride coating is a coating containing an iron chloride component, and the potassium ferrocyanide coating is a coating containing a potassium ferrocyanide component. Both the iron chloride coating and the potassium ferrocyanide coating are coatings dissolved in an aqueous solution and / or an alcohol solution. The pattern of the colored round wire group 7 is blue.

[0061] The beneficial effects of adopting the above embodiment are as follows: When the iron chloride coating and the potassium ferrocyanide coating come into contact with each other, bright-colored Prussian blue will be generated, with a high color display contrast, sensitive reaction, and irreversible reaction, avoiding misjudgment caused by reversible reactions. Moreover, the selected chemical substances are non-toxic and harmless, meeting the safety standards of respiratory protection equipment, and the two coating materials also have low costs, being suitable for industrial production. In addition, the iron chloride coating and the potassium ferrocyanide coating have good material adhesion and can stably adhere to the surface of the transparent pane 2 or the airtight elastic diaphragm 5. And the self-colors of the two materials are relatively light. After iron chloride is dissolved in water, iron ions (Fe 3+ ) hydrolyze to form iron hydroxide (Fe(OH)3) colloid or a small amount of precipitate, presenting a light yellowish-brown color. After potassium ferrocyanide is dissolved in water, it presents a light yellow color according to different concentrations, facilitating the observation of the color display effect.

[0062] When potassium ferrocyanide encounters water alone, it is light yellow or colorless and does not hydrolyze. Iron chloride is soluble in water and is yellowish-brown. Iron chloride has strong hygroscopicity and can absorb moisture in a humid environment. When they react with water, Prussian blue precipitate is formed, which is dark blue. A small part of the water vapor breathed by the user will pass through the filter cotton 4 and reach the other side of the filter cotton 4 (i.e., the space between the filter cotton 4 and the transparent pane 2), thereby contacting the iron chloride and potassium ferrocyanide and making them have a certain degree of humidity.

[0063] Under anhydrous conditions, when potassium ferrocyanide and iron chloride are in contact with each other in solid form, obvious chemical reactions are not likely to occur, but they can be attached to the airtight elastic diaphragm 5 and the transparent pane 2 by means of a process. The relevant process parameters of the first coating 3 and the second coating 6 are as follows:

[0064] The formulation ratio of the first coating 3: 5% FeCl3 ethanol solution plus 0.5% silane coupling agent. The formulation ratio of the second coating 6: 3% K4[Fe(CN)6] aqueous solution plus 1% polyvinyl alcohol (PVA) binder.

[0065] Coating process of the first coating 3: Roller-coated onto the transparent pane 2 and dried at a temperature of 60°C for 3 minutes. Coating process of the second coating 6: Sprayed onto the airtight elastic diaphragm 5, and then irradiated with ultraviolet light with a wavelength of 365 nm for 30 seconds to quickly cure the second coating 6, thereby forming a protective film with certain properties.

[0066] At the initial stage of use of the filter cotton 4, the breathing resistance is relatively small, and the pressure difference on both sides of the filter cotton 4 during the breathing process is relatively small, so the deformation of the airtight elastic diaphragm 5 is also relatively small. As time goes by, the breathing resistance slowly increases, and the deformation of the airtight elastic diaphragm 5 also gradually increases until the locally airtight elastic diaphragm 5 that bulges outward contacts the transparent pane 2. Under the action of the exhaled water vapor, the originally light tan ferric chloride coating reacts with the pale yellow potassium ferrocyanide coating to produce a color reaction, leaving an irreversible colored Prussian blue area on the transparent pane 2, and the color difference between yellow and blue is obvious. As breathing continues, the breathing resistance continues to increase, the water vapor in the breathing filter box increases, and the airtight elastic diaphragm 5 and the transparent pane 2 will come into contact several times, and the contact area is related to the breathing resistance. Finally, a colored circular pattern 8 with a darker inner part and a lighter outer part will be left on the transparent pane 2. Because along the radial direction outward, the pattern color of the colored circular line group 7 fades, and the color of the actually formed colored circular pattern 8 also generally fades along the radial direction outward. Therefore, when any single circular line in the colored circular line group 7 is hidden in the colored circular pattern 8, it is judged that the breathing resistance of this breathing filter box is too large and has reached the service life, and the transparent pane 2, filter cotton 4, and airtight elastic diaphragm 5 should be replaced in time.

[0067] Figures 1 to 4 is a simplified schematic solution of the breathing filter box with self-detection of resistance in the present application, and Figures 5 to 16 is a further refined design solution of the breathing filter box with self-detection of resistance in the present application. In one embodiment, the housing includes an outer half-shell 1 and an inner half-shell 9 that are assembled in a detachable manner. An air-permeable seam 10 is formed between the outer half-shell 1 and the inner half-shell 9, as Figure 7 shown, Figure 7 in which several arrows are used to show that when inhaling, air enters the interior of the breathing filter box from the air-permeable seam 10. The inner half-shell 9 is provided with an air flow interface 902 for the breathing air flow to pass through, and the air flow interface 902 is closer to the user's mouth and nose. The transparent pane 2 is assembled with the outer half-shell 1 in a detachable and airtight manner, and is kept airtight during assembly. The airtight elastic diaphragm 5 is detachably assembled with the inner half-shell 9.

[0068] The beneficial effects of adopting the above-mentioned embodiments are as follows: An air-permeable seam 10 is formed between the outer half-shell 1 and the inner half-shell 9, ensuring a sufficiently wide breathing air path inside the breathing filter box. The detachable assembly design of the transparent window pane 2 and the air-impermeable elastic diaphragm 5 realizes modular replacement. The user only needs to replace disposable consumables such as the transparent window pane 2, the filter cotton 4, and the air-impermeable elastic diaphragm 5. When the filter cotton 4 reaches its actual service life, the transparent window pane 2, the filter cotton 4, and the air-impermeable elastic diaphragm 5 are replaced together, while the housing of the breathing filter box can be reused.

[0069] In a non-limiting example, as Figure 7 shown, several rib plates 106 protrude from the inner wall of the outer half-shell 1. The rib plates 106 can enhance the structural strength of the outer half-shell 1, and at the same time, while hardly hindering the air-permeable seam 10, keep the air-permeable seam 10 wide enough.

[0070] When the user inhales, the external air enters between the outer half-shell 1 and the inner half-shell 9 (i.e., the air-permeable seam 10) along the route indicated by the arrow as Figure 7 shown. Then the air enters the inner half-shell 9 in a U-shaped turn, then passes through the filter cotton 4, and finally passes through the air flow interface 902 and enters the user's mouth and nose. When the user exhales, the exhaled gas enters the inner half-shell 9 from the air flow interface 902, then passes through the filter cotton 4, and then enters between the outer half-shell 1 and the inner half-shell 9 (i.e., the air-permeable seam 10) in a U-shaped turn, and finally is discharged into the external air.

[0071] When the filter cotton 4 has been used for a long time and causes a large breathing resistance, when the user inhales, the air flow cannot pass through the filter cotton 4 very smoothly. The air flow pressure will act on the air-impermeable elastic diaphragm 5, causing it to bulge significantly towards the transparent window pane 2 direction, and even causing the bulging air-impermeable elastic diaphragm 5 to contact the transparent window pane 2. When the user exhales, the air flow also cannot pass through the filter cotton 4 very smoothly. The air flow pressure will act on the air-impermeable elastic diaphragm 5, causing it to have a significant concave towards the air flow interface 902 direction. At this time, the air-impermeable elastic diaphragm 5 and the transparent window pane 2 will not be in contact. Therefore, the moment of contact color display generally occurs when the user exhales.

[0072] In a non-limiting example, the outer half-shell 1 and the inner half-shell 9 can be assembled by snap connection. As Figure 7 shown, the inner wall of the outer half-shell 1 has a first snap portion 103 with a cantilevered protrusion. As Figure 10 shown, the outer wall of the inner half-shell 9 specifically has a second snap portion 903 with a protrusion. The first snap portion 103 and the second snap portion 903 are snap-connected to each other.

[0073] In one embodiment, the air flow interface 902, the first coating 3, the second coating 6, and the colored wire group 7 are coaxially arranged.

[0074] The beneficial effects of adopting the above embodiment are: the coaxial arrangement ensures that the pressure difference generated by the breathing airflow can directly act on the central area of the airtight elastic diaphragm 5, making the concave-convex deformation of the middle part of the airtight elastic diaphragm 5 more regular and symmetrical, facilitating the formation of a nearly circular contact surface between the first coating 3 and the second coating 6, thereby improving the sensitivity of detection. The coaxial design also optimizes the internal space layout of the breathing filter box, making its structure more compact, leaving more effective space in the breathing filter box for the filter cotton 4.

[0075] In one embodiment, if Figure 5 As shown, the outer half shell 1 includes a first main opening 101, the inner half shell 9 includes a second main opening 901, the opening area of the second main opening 901 is smaller than the opening area of the first main opening 101, and the filter cotton 4 and the airtight elastic membrane 5 jointly cover the second main opening 901. Figure 10 and Figure 13 , the area occupied by the filter cotton 4 relative to the second main opening 901 is greater than the area occupied by the airtight elastic membrane 5 relative to the second main opening 901. One cavity of the housing is located on one side of the second main opening 901, the other cavity of the housing is located on the other side of the filter cotton 4 and the airtight elastic membrane 5 away from the above-mentioned one side, and the airflow interface 902 is located in the other cavity.

[0076] The beneficial effects of the above embodiment are: the filter cotton 4 covers a larger area, which can effectively intercept particulate matter in the air, ensure the filtering efficiency of the breathing filter box, and ensure the basic function of the breathing filter box. The airtight elastic diaphragm 5 covers a smaller area, which does not affect the filtering performance of the filter cotton 4 too much. The airtight elastic diaphragm 5 focuses on the induction of breathing resistance. Through reasonable area allocation, while ensuring the filtering effect, the airtight elastic diaphragm 5 can respond to the change of breathing resistance in a timely and accurate manner, thereby triggering the color reaction of the coating.

[0077] In a non-limiting example, Figure 10 As shown, the second main opening 901 of the inner half shell 9 has a transverse dividing rib 905, and the dividing rib 905 divides the second main opening 901 into a first hole 9011 and a second hole 9012. The area of the first hole 9011 is larger than the area of the second hole 9012. The filter cotton 4 is responsible for covering the first hole 9011, and the airtight elastic membrane 5 is responsible for covering the second hole 9012. In this way, the filter cotton 4 and the airtight elastic membrane 5 can be independent components and do not need to be fixed together.

[0078] In a non-limiting example, Figure 9 As shown, the airflow interface 902 has a sinking pipe 906 extending into the inner half shell 9, the side and end faces of the sinking pipe 906 are hollow, and the end of the sinking pipe 906 abuts against the filter cotton 4, which can ensure that the filter cotton 4 is stably limited in the inner half shell 9.

[0079] In one embodiment, as Figure 11 and Figure 12 shown, the airtight elastic diaphragm 5 includes a strip plate 501. Both ends of the strip plate 501 in the length direction are detachably clamped to the inner half shell 9 (refer to Figure 13 ), the middle part of the strip plate 501 has a circular elastic membrane area 503, the flexibility of the elastic membrane area 503 is greater than that of the strip plate 501, and the second coating 6 is located in the elastic membrane area 503.

[0080] The beneficial effect of adopting the above embodiment is that such a design allows the strip plate 501 to be made of a conventional plastic part, making the outer peripheral part of the airtight elastic diaphragm 5 have a certain rigidity, so as to facilitate the layout of the clamping mechanism, and only need to ensure that the elastic membrane area 503 is made of a flexible material. For example, the elastic membrane area 503 is made of medical-grade silicone, such as polydimethylsiloxane (PDMS), and the thickness range is 50 μm to 100 μm.

[0081] Ensure that the deformation of the airtight elastic diaphragm 5 is linearly related to the pressure difference on both sides of the filter cotton 4. A circular elastic membrane area 503 is provided in the middle, and its flexibility is greater than that of the strip plate 501. The second coating 6 is located in the elastic membrane area 503. Because the flexible elastic membrane area 503 in the middle is relatively high, more obvious concave and convex deformations can be generated under the action of the pressure difference, enhancing the response ability to the change of breathing resistance. The circular elastic membrane area 503 matches the circular contour of the second coating 6, ensuring that the coating contact area is uniform and the color reaction is symmetric and stable, improving the sensitivity and reliability of resistance detection. The contour of the elastic membrane area 503 can be circular, and the diameter of the contour of the elastic membrane area 503 can be greater than the diameter of the contour of the second coating 6.

[0082] In one embodiment, as Figure 15 shown, the outer half shell 1 includes a base plate 1091 and an enclosing plate 1092 arranged around the edge of the base plate 1091. The base plate of the outer half shell 1 has a through window hole 102 (refer to Figure 5 ), the edge of the window hole 102 intersects with the enclosing plate, and the airtight transparent window pane 2 is assembled with the window hole 102. As Figure 15 、 Figure 16 shown, the edge of the window hole 102 has a three-sided groove structure, and there is a T-shaped groove 104 in the three-sided groove structure. The edge of the transparent window pane 2 has a T-shaped edge 201 that is movably assembled with the T-shaped groove 104. From the cross-sectional view, the T-shaped edge 201 and the T-shaped groove 104 are concavo-convexly fitted. As Figure 15 shown, Figure 15 the transparent window pane 2 in Figure 15 is in a separated state from the breathing filter box, and

[0083] The beneficial effects of adopting the above embodiments are as follows: The transparent pane 2 is slidably assembled with the T-shaped groove 104 of the outer half shell 1 through the T-shaped edge 201 on the edge. The three-sided groove structure ensures the airtightness between the transparent pane 2 and the outer half shell 1, preventing external air from leaking through the window hole 102 and ensuring the sealing performance of the breathing filter box. It takes into account the detachability, sealing performance and observation convenience of the transparent pane 2.

[0084] In a non-limiting example, as Figure 5 shown, the three-sided groove structure is formed by connecting a T-shaped groove 104, a terminal groove 105, and a T-shaped groove 104 in sequence end to end. Both the T-shaped groove 104 and the terminal groove 105 are straight grooves. From the cross-sectional view, the terminal groove 105 is also a rectangular groove. The two T-shaped edges 201 are arranged in parallel. One side of the transparent pane 2 has a bulged hand-held part 202 (see Figure 14 ), which is convenient for personnel to pinch with their fingers and perform the actions of disassembling or assembling the transparent pane 2, improving the human-computer interaction experience.

[0085] In a non-limiting example, as Figure 14 shown, in order to reduce the alignment accuracy requirements for each new transparent pane 2, one side of the transparent pane 2 also has a chamfer 203, and the chamfer 203 and the hand-held part 202 are located on both sides of the transparent pane 2 respectively.

[0086] In a non-limiting example, see Figure 7 , the main structure of the inner half shell 9 is similar to that of the outer half shell 1, and also includes a base plate 1091 and an enclosing plate 1092 arranged around the edge of the base plate 1091. The air flow interface 902 is located on the base plate 1091 of the inner half shell 9.

[0087] In a non-limiting example, the airtight elastic diaphragm 5 is detachably snap-fitted with the inner half shell 9. As Figure 11 , Figure 12 shown, both ends of the airtight elastic diaphragm 5 have male fasteners 502, and the surface of the inner half shell 9 has female fasteners 904. The assembly or separation of the male fasteners 502 and the female fasteners 904 realizes the assembly or separation of the airtight elastic diaphragm 5 and the inner half shell 9. The length extension direction of the male fastener 502 can be perpendicular to the length direction of the airtight elastic diaphragm 5 itself.

[0088] The present application provides a protective mask. As Figure 17 shown, it includes the above-mentioned breathing filter box with self-resistance detection.

[0089] As Figure 17 shown, the protective mask includes a silicone mask cover 11 that covers the user's mouth and nose. The breathing filter boxes with self-resistance detection of the present application are arranged on the left and right sides of the silicone mask cover 11 respectively. The breathing filter box docks with the silicone mask cover 11 through its own air flow interface 902.

[0090] In actual use, the normal service life of a piece of filter cotton 4 may be several days. The user can observe the colored circular pattern 8 on the transparent window pane 2 every time when putting on and taking off the protective mask, so as to judge whether the filter cotton 4 has reached the time to be replaced.

[0091] The modular breathing filter box can be symmetrically arranged on both sides of the protective mask. This protective mask is compatible with a variety of working scenarios and is especially suitable for explosion-proof environments such as mines. The explosion-proof batteries used in all electronic equipment used in general mines are expensive, about 10 to 20 times that of ordinary batteries. This protective mask integrates the technical advantages of the breathing filter box into labor protection products. It is not battery-powered, light in weight and low in cost. It improves the protection safety, ease of use and environmental adaptability, and has broad application prospects, especially in special environments with explosion-proof requirements.

[0092] The above embodiments are only for illustrating the technical concept and features of the present application, and their purpose is to enable people familiar with this technology to understand the content of the present application and implement it. They cannot be used to limit the scope of protection of the present application. All equivalent changes or modifications made according to the spirit of the present application should be included in the scope of protection of the present application.

Claims

1. A breathing filter cartridge with self-detection of resistance, characterized in that, Comprising: A housing, inside which a filter cotton (4) is detachably arranged; An airtight elastic diaphragm (5), which is located inside the housing. The airtight elastic diaphragm (5) and the filter cotton (4) divide the cavity of the housing into two parts. The breathing airflow resistance inside the housing can form a pressure difference on both sides of the filter cotton (4), and the airtight elastic diaphragm (5) can undergo elastic concave and convex deformation along with the pressure difference; A transparent pane (2), which is located on the surface of the housing; Wherein, a first coating (3) is arranged on the side of the transparent pane (2) facing the airtight elastic diaphragm (5), and a second coating (6) is arranged on the side of the airtight elastic diaphragm (5) facing the transparent pane (2). After the first coating (3) and the second coating (6) come into contact with each other, they can change color or develop color.

2. The breathing filter cartridge with self-detection of resistance according to claim 1, wherein: A colored circular line group (7) including several concentric circles is arranged on the transparent pane (2). The color of the colored circular line group (7) becomes lighter towards the outside along the radial direction; The contours of the first coating (3) and the second coating (6) are both circular.

3. The breathing filter cartridge with self-detection of resistance according to claim 1, wherein: The first coating (3) and the second coating (6) can undergo an irreversible chemical color development reaction after coming into contact with each other under the action of breathing water vapor.

4. The breathing filter cartridge with self-detection of resistance according to claim 1, characterized in that: The first coating (3) and the second coating (6) are each optionally a ferric chloride coating or a potassium ferrocyanide coating, and the materials of the first coating (3) and the second coating (6) are different from each other.

5. The breathing filter cartridge with self-detection of resistance according to claim 1, wherein: The housing includes an outer half-shell (1) and an inner half-shell (9) assembled in a detachable manner. An air-permeable seam (10) is formed between the outer half-shell (1) and the inner half-shell (9). The inner half-shell (9) is provided with an air flow interface (902) for breathing airflow to pass through; The transparent pane (2) is assembled with the outer half-shell (1) in a detachable and airtight manner, and the airtight elastic diaphragm (5) is detachably assembled in the inner half-shell (9).

6. The breathing filter cartridge with self-detection of resistance according to claim 5, wherein: The air flow interface (902), the first coating (3), and the second coating (6) are coaxially arranged with each other.

7. The breathing filter cartridge with self-detection of resistance according to claim 5, characterized in that: The outer half-shell (1) has a first main opening (101), and the inner half-shell (9) has a second main opening (901). The opening area of the second main opening (901) is smaller than the opening area of the first main opening (101). The filter cotton (4) and the airtight elastic diaphragm (5) jointly cover the second main opening (901); The covering area of the filter cotton (4) on the second main opening (901) is larger than the covering area of the airtight elastic diaphragm (5) on the second main opening (901); One cavity of the housing is located on one side of the second main opening (901), and the other cavity of the housing is located on the other side of the filter cotton (4) and the airtight elastic diaphragm (5) away from the said side. The air flow interface (902) is located in the other cavity.

8. The breathing filter cartridge with self-detection of resistance according to claim 5, characterized in that: The airtight elastic diaphragm (5) includes a strip plate (501). Both ends of the strip plate (501) in the length direction are detachably assembled with the inner half shell (9). The middle part of the strip plate (501) has a circular elastic membrane area (503). The flexibility of the elastic membrane area (503) is greater than that of other positions of the strip plate (501). The second coating (6) is located in the elastic membrane area (503).

9. The breathing filter cartridge with self-detection of resistance according to claim 5, characterized in that: The outer half shell (1) includes a base plate (1091) and an enclosing plate (1092) arranged around the edge of the base plate (1091). The base plate (1091) of the outer half shell (1) has a through window hole (102). One edge of the window hole (102) intersects with the enclosing plate (1092). The transparent window pane (2) is assembled with the window hole (102). The edge of the window hole (102) has a three-sided groove structure, and the three-sided groove structure includes a T-shaped groove (104). The edge of the transparent window pane (2) has a T-shaped rib (201) that is hermetically and movably assembled with the T-shaped groove (104).

10. A protective mask, characterized in that, A breathing filter cartridge with self-detection of resistance according to any one of claims 1 to 9.

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