Gas sensor

Abstract

The application discloses a gas sensor, comprising a shell, a cover plate and a waterproof and breathable film, the shell has an inner cavity, the shell has a side wall, the side wall is located at the periphery of the inner cavity, the side wall is provided with a first through hole part, the first through hole part comprises a first through hole penetrating through the side wall, the first through hole is in gas communication with the inner cavity and the outside of the shell; the cover plate is welded with the side wall, the cover plate has a second through hole part, the second through hole part comprises a second through hole penetrating through the cover plate; at least part of the waterproof and breathable film is located between the first through hole part and the second through hole part. The gas sensor of the application can fix the waterproof and breathable film between the cover plate and the side wall, and reduce the risk of falling off of the waterproof and breathable film.

Description

Technical Field

[0001] This invention relates to the field of gas detection technology, and more specifically to a gas sensor. Background Technology

[0002] The gas sensor includes a housing with an inner cavity forming a gas chamber for gas flow. The housing has sidewalls with vents for gas inlet and outlet. The gas sensor also includes a waterproof and breathable membrane, which is adhered to the housing and covers the vents to reduce water molecule ingress into the gas chamber. The adhesive used to bond the waterproof and breathable membrane is prone to loss of adhesion due to aging or deterioration, posing a risk of membrane detachment. Therefore, related technologies also include a fastener for securing the waterproof and breathable membrane, which engages with the housing to clamp the membrane between the fastener and the housing. However, this engagement requires specific, mutually cooperating engagement structures on both the fastener and the housing; if the fastener fails to engage properly, the risk of membrane detachment remains.

[0003] Therefore, it is necessary to provide a gas sensor to solve the above problems. Summary of the Invention

[0004] The purpose of this invention is to provide a gas sensor that solves the problem of waterproof and breathable membranes easily detaching from the housing.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A gas sensor, comprising a housing, a cover plate, and a waterproof and breathable membrane,

[0007] The housing has an inner cavity and a side wall located around the inner cavity. The side wall has a first through hole, which penetrates the side wall and provides gaseous communication between the inner cavity and the outside of the housing.

[0008] The cover plate is welded to the side wall, and the cover plate has a second through hole, the second through hole including a second through hole penetrating the cover plate;

[0009] At least a portion of the waterproof and breathable membrane is located between the first through-hole portion and the second through-hole portion.

[0010] In this application, the housing has a sidewall with a first through hole, a cover plate is welded to the sidewall with a second through hole, and at least a portion of the waterproof and breathable membrane is located between the first and second through holes, thus fixing the waterproof and breathable membrane between the cover plate and the sidewall and reducing the risk of the waterproof and breathable membrane falling off. Attached Figure Description

[0011] Figure 1 This is a three-dimensional structural diagram of a gas sensor according to a specific embodiment of the present invention;

[0012] Figure 2 for Figure 1 The diagram shows the exploded structure of the gas sensor.

[0013] Figure 3 for Figure 1 A schematic diagram of a partial explosion structure of the gas sensor shown.

[0014] Figure 4 This is a schematic diagram of the cover plate according to a specific embodiment of the present invention;

[0015] Figure 5 This is a side view of the cover plate according to a specific embodiment of the present invention;

[0016] Figure 6 for Figure 1 A schematic diagram of the cross-sectional structure of the gas sensor shown.

[0017] Figure 7 for Figure 1 The diagram shows a longitudinal cross-sectional view of the gas sensor. Detailed Implementation

[0018] The exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. If several embodiments exist, features in these embodiments may be combined with each other without conflict. When the description refers to the drawings, unless otherwise stated, the same numbers in different drawings represent the same or similar elements. The descriptions in the following exemplary embodiments do not represent all embodiments consistent with the present invention; rather, they are merely examples of apparatuses, products, and / or methods consistent with some aspects of the present invention as set forth in the claims.

[0019] The terminology used in this invention is for the purpose of describing particular embodiments only and is not intended to limit the scope of protection of this invention. The singular forms “a,” “the,” or “the” as used in the specification and claims of this invention are also intended to include the plural forms unless the context clearly indicates otherwise.

[0020] It should be understood that the terms "first," "second," and similar words used in the specification and claims of this invention do not indicate any order, quantity, or importance, but are merely used to distinguish features. Similarly, the terms "an" or "a" do not indicate a quantity limitation, but rather indicate the presence of at least one. Unless otherwise stated, the terms "before," "after," "upper," "lower," and similar words appearing in this invention are for ease of explanation only and are not limited to a specific location or spatial orientation. The terms "comprising" or "including" are an open-ended expression, meaning that the element preceding "comprising" or "including" encompasses the element following "comprising" or "including" and its equivalents, but this does not preclude the element preceding "comprising" or "including" from also including other elements. In this invention, the term "several" means two or more.

[0021] Please see Figures 1 to 7 As shown, this embodiment discloses a gas sensor, which includes a housing 10, a cover plate 20, and a waterproof and breathable membrane 30 located between the housing 10 and the cover plate 20.

[0022] Please see Figures 1 to 3 As shown, the housing 10 has an inner cavity 11 and a sidewall 12, with the sidewall 12 located around the inner cavity 11. The sidewall 12 includes a first sidewall 121 and a second sidewall 122, extending along a direction perpendicular to the length of the housing 10. Figure 1 The direction of the middle arrow indicates the length direction of the housing 10. The first sidewall 121 and the second sidewall 122 are located on both sides of the inner cavity 11, respectively. In some embodiments, the first sidewall 121 and the second sidewall 122 are arranged opposite to each other and parallel to each other, for example... Figure 6 As shown. The sidewall 12 is provided with a first through-hole 13, which includes a first through-hole 131 penetrating through the sidewall 12, providing gaseous communication between the inner cavity 11 and the outside of the housing 10. Both the first sidewall 121 and the second sidewall 122 are provided with first through-holes 13. Both the first sidewall 121 and the second sidewall 122 are provided with grooves 14, which are recessed from the outer surface of the housing 10 towards the interior of the housing 10. The first through-hole 13 is located between the groove 14 and the inner cavity 11.

[0023] Please see Figures 4 to 6 As shown, the cover plate 20 is welded to the side wall 12. Welding is a manufacturing process that joins metals or other thermoplastic materials by heating, high temperature, or high pressure. In some embodiments, both the cover plate and the housing are made of metal, or both are made of thermoplastic materials.

[0024] Please see Figure 3 and Figure 6As shown, the cover plate 20 covers the first through-hole portion 13, and the cover plate 20 has a second through-hole portion 21, which has multiple portions. Each second through-hole portion 21 includes a second through-hole 211 penetrating the cover plate 20. At least a portion of the waterproof and breathable membrane 30 is located between the side wall 12 and the cover plate 20, and at least a portion of the waterproof and breathable membrane 30 is located between the first through-hole portion 13 and the second through-hole portion 21. Thus, the waterproof and breathable membrane 30 is sandwiched between the side wall 12 and the cover plate 20, allowing external gas to sequentially enter the inner cavity 11 of the housing through the second through-hole 211, the waterproof and breathable membrane 30, and the first through-hole 131.

[0025] In some embodiments, the housing 10 includes a first wall surface 132 located around the first through hole 131. Along the extending direction of the first through hole 131, the projection of the first wall surface 132 onto the cover plate 20 lies within the outer contour of the cover plate 20, and the projection of the first wall surface 132 onto the waterproof and breathable membrane 30 lies within the outer contour of the waterproof and breathable membrane 30. Thus, the first through hole 13 is completely covered by the cover plate 20 and the waterproof and breathable membrane 30, reducing the entry of external water molecules into the housing cavity 11 through the first through hole 131.

[0026] In some embodiments, the cover plate 20 includes a second wall surface 212 located around the second through hole 211. Along the extending direction of the second through hole 211, the projection of the second wall surface 212 onto the waterproof and breathable membrane 30 lies within the outer contour of the waterproof and breathable membrane 30. Thus, the second through hole portion 21 is completely covered by the waterproof and breathable membrane 30.

[0027] In some embodiments, the cover plate 20 includes a filter section 22 and a connecting section 23. A second through-hole section 21 is disposed on the filter section 22. The filter section 22 is connected to the connecting section 23, which is located on the periphery of the filter section 22 and connected to the side wall 12. The filter section 22 and the connecting section 23 are not on the same plane. The filter section 22 is farther away from the side wall 12 relative to the connecting section 23, thereby creating a gap between the filter section 22 and the side wall 12 for accommodating the waterproof and breathable membrane 30. The connecting section 23 is located on the periphery of the waterproof and breathable membrane 30, for example... Figure 6 As shown. This reduces lateral movement of the waterproof and breathable membrane 30 between the sidewall 12 and the cover plate 20. In some embodiments, the cover plate 20 is entirely a filter structure; that is, both the filter portion 22 and the connecting portion 23 have filter structures, for example... Figure 6 As shown.

[0028] In some embodiments, the filter portion 22 and the connecting portion 23 are integrally formed, and the connecting portion 23 is formed by bending the outer edge of the filter portion 22. Further, along the extending direction of the first through hole 131, the projection of the first through hole portion 13 onto the cover plate 20 is located within the outer contour of the cover plate 20, that is, the cover plate 20 completely covers the first through hole portion 13, and the cover plate 20 is at least partially located within the groove 14. In some embodiments, the connecting portion 23 is located within the groove 14. In some embodiments, the cover plate 20 is located within the groove 14, for example... Figure 6 As shown. This facilitates the installation of the cover plate 20 and the housing 10.

[0029] In some embodiments, the projection of the waterproof and breathable membrane 30 onto the cover plate 20 lies within the outer contour of the cover plate 20, meaning the cover plate 20 completely covers the waterproof and breathable membrane 30. Further, the projection of the waterproof and breathable membrane 30 onto the filter screen portion 22 lies within the outer contour of the filter screen portion 22, or the projection of the waterproof and breathable membrane 30 onto the filter screen portion 22 coincides with the outer contour of the filter screen portion 22, for example... Figure 6 As shown. The connecting portion 23 is formed by bending the outer edge of the filter portion 22, thus creating a gap between the filter portion 22 and the side wall 122 for accommodating the waterproof and breathable membrane 30, reducing the lateral movement of the waterproof and breathable membrane 30 between the side wall 122 and the cover plate 20. In this specific embodiment, the waterproof and breathable membrane 30 is completely located within the groove 14, and the cover plate 20 is also completely located within the groove 14. The waterproof and breathable membrane 30 has a first surface 31 and a second surface 32, with the first surface 31 contacting the side wall 12 and the second surface 32 contacting the cover plate 20. There is no gap between the waterproof and breathable membrane 30 and the first through-hole portion 13, nor is there a gap between the waterproof and breathable membrane 30 and the second through-hole portion 21. That is, the waterproof and breathable membrane 30 is clamped between the side wall 12 and the cover plate 20. In this way, radial movement of the waterproof and breathable membrane 30 between the first through-hole portion 13 and the second through-hole portion 21 can be reduced. The outer surface of the filter section 22 is flush with the side wall 12 except for the groove 14. In this way, the fluid needs to pass through the second through hole 211, the waterproof and breathable membrane 30 and the first through hole 131 in one go. Liquid is difficult to enter the gas sensor, thus greatly improving the waterproof effect.

[0030] In some embodiments, the cover plate 20 is welded to the outer surface of the sidewall 12. Specifically, the connecting portion 23 is welded to the outer surface of the groove 14. In this way, the waterproof and breathable membrane 30 can be fixed between the housing 10 and the cover plate 20, effectively reducing the risk of the waterproof and breathable membrane 30 falling off.

[0031] Please see Figure 6As shown, the first sidewall 121 and the second sidewall 122 are arranged opposite to each other and parallel to each other, and the first through hole 131 on the first sidewall 121 and the first through hole 131 on the second sidewall 122 are opposite to each other; thus, it is beneficial for the flow of gas in the inner cavity 11 of the housing. Of course, the present invention does not limit the direction of gas inflow and outflow.

[0032] Based on the above embodiments, there are at least two first through holes 131, and the extension directions of at least two first through holes 131 are the same. Similarly, there are at least two second through holes 211, and the extension directions of at least two second through holes 211 are the same. This ensures uniform gas flow. Since the extension directions of the first through holes 131 and the second through holes 211 are the same, the gas flow efficiency between the outside and inside of the sensor is higher, thereby improving the overall efficiency of the gas sensor. The inner diameter of the second through hole 211 is smaller than the inner diameter of the first through hole 131. Thus, the second through hole 211 and the waterproof and breathable membrane 30 block liquid from entering, allowing gas to pass through the second through hole 211 and the waterproof and breathable membrane 30. The larger inner diameter of the first through hole 131 then allows gas to more easily enter the sensor's inner cavity 11, further improving the overall efficiency of the gas sensor. Furthermore, the smaller inner diameter of the second through hole 211 compared to the first through hole 131 effectively blocks external impurities, reducing their adhesion to the waterproof and breathable membrane 30 and its impact on gas flow.

[0033] Further, please refer to Figure 1 and Figure 6 As shown, in addition to the first sidewall 121 and the second sidewall 122, the sidewall 12 also includes other sidewalls connecting the first sidewall 121 and the second sidewall 122, with at least two other sidewalls, so that the first sidewall 121, the second sidewall 122, and the other sidewalls form a closed loop. In this specific embodiment, the sidewall 12 includes the first sidewall 121, the second sidewall 122, and two other sidewalls, making the outer surface of the housing 10 into a cuboid shape. Of course, in other embodiments, the housing 10 can also be other shapes instead of a fixed cuboid shape. In this specific embodiment, the use of a cuboid shape is to facilitate the installation and fixation of the entire gas sensor, and also to make the entire structure more symmetrical and regular, and to have a sufficiently long optical path, so as to make the gas sensor more efficient.

[0034] In another specific embodiment, other sidewalls are also provided with first through holes 13 and grooves 14, with the cover plate 20 and the waterproof and breathable membrane 30 placed within the grooves 14. This ensures the waterproof performance of the entire gas sensor while improving gas flow efficiency.

[0035] Specifically, the waterproof and breathable membrane 30 mainly consists of three layers: PP spunbond nonwoven fabric, PE polymer breathable membrane, and PP spunbond nonwoven fabric. The spunbond nonwoven fabric primarily enhances tensile strength and hydrostatic pressure, and protects the middle layer, i.e., the breathable membrane. True breathability relies mainly on the middle layer, the PE polymer breathable membrane. The working principle of the waterproof and breathable membrane 30 is as follows: In the state of water vapor, water particles are very small. According to the principle of capillary motion, they can easily permeate to the other side of the capillary, thus causing vapor permeation. When water vapor condenses into water droplets, the particles become larger. Due to the surface tension of the water droplets, i.e., the water molecules "pull and resist" each other, the water molecules cannot easily detach from the water droplets and permeate to the other side, thus preventing water penetration and giving the breathable membrane its waterproof function.

[0036] Please see Figure 4 As shown, based on the above embodiment, the second through hole 211 on the filter part 22 allows gas to pass through while blocking liquids or other impurities. The protection rating of the filter part 22 is IP54 or IP67. IP is short for INTERNATIONAL PROTECTION, which refers to an internationally recognized protection rating. The IP protection rating is generally composed of two numbers or supplementary letters: the first number indicates the level of protection against solid ingress, and the second number indicates the level of protection against water ingress. The larger the number, the higher the protection rating. For example, IP68, where 6 indicates level 6 dustproof and 8 indicates level 8 waterproof. Therefore, when the protection rating of the mesh surface 31 in this invention is IP54, IP54 means that the dustproof rating is level 5 and the waterproof rating is level 4 (dustproof rating IP5X: prevents the accumulation of harmful dust; waterproof rating IPX4: liquids splashed onto the casing from any direction will not cause damage). When the filter part 22 in this invention has a protection rating of IP67, IP67 means a dustproof rating of 6 and a waterproof rating of 7 (dustproof rating IP6X: protection against dust inhalation; waterproof rating IPX7: protection against brief immersion). This gas sensor, due to its high protection rating and excellent sealing performance, can be applied to some complex scenarios.

[0037] Please see Figure 2 and Figure 7As shown, the gas sensor of the present invention also includes a light source 40, a detector 50, and a circuit board. Both the light source 40 and the detector 50 are electrically connected to the circuit board and are located on the periphery of the inner cavity 11. The light source 40 and the detector 50 are located at opposite ends of the inner cavity 11 along the length of the housing 10. The gas sensor's gas chamber 60 is formed by the light source 40, the detector 50, and the inner cavity 11. The light source 40 is the input end, including a light source and a condenser cup, while the detector 50 is the output end, including a detector and a filter. The light source 40 emits infrared light, which passes through the condenser cup and irradiates the gas entering the gas chamber 60. The infrared light inside the gas chamber 60 is reflected multiple times on the wall of the inner cavity 11, repeatedly irradiating the gas to be measured. The light then passes through the filter and finally reaches the detector to complete gas detection. Gas detection is based on the light changes of the infrared light emitted by the light source within the gas chamber 60. Furthermore, the input and output terminals are connected to the circuit board via pin 70, enabling the gas sensor to receive and output information, and also to be powered on through the connection with the circuit board.

[0038] Further, please refer to Figure 7 As shown, the inner cavity 11 of the housing 10 is a circular channel opened through the center of the cross-section of the housing 10, that is, the air chamber 60 is a cylindrical channel, so that infrared light can be effectively reflected within the air chamber 60. The light source of the light source unit 40 is connected to the circuit board through the pin 70. The light source unit 40 is also provided with a light source base, which is circular and the same size as the cross-section of the inner cavity 11. The end of the light source base away from the air chamber 60 is also provided with a boss with a diameter larger than the diameter of the inner cavity 11. One end of the inner cavity 11 is provided with a corresponding annular groove. In this way, the light source unit 40 can be effectively sealed, and the light source unit 40 is fixedly set at one end of the housing 10 and will not move within the inner cavity 11. A small hole is opened in the center of the light source base, and the light source is fixedly installed in the small hole of the light source base. The condenser cup is formed into a circle with the same cross-sectional shape and size as the light source base. There is a certain distance between the light source and the condenser cup, ensuring that the infrared light emitted by the light source can be concentrated and all of it can pass through the condenser cup and enter the air chamber 60. The detector of the detection unit 50 is connected to the circuit board via pin 70. The detection unit 50 is also provided with a detector base for fixing the detector. The detector base is circular and has the same cross-section as the inner cavity 11. The end of the detector base away from the air chamber 60 is also provided with a boss with a diameter larger than the inner cavity 11. The other end of the inner cavity 11 is provided with a corresponding annular groove. In this way, the detection unit 50 can be effectively sealed, and the detection unit 50 is fixedly set at the other end of the housing 10 without moving within the inner cavity 11. The detector is fixedly installed on the detector base.

[0039] Furthermore, the housing 10 and the cover plate 20 are integrally connected, and the waterproof and breathable membrane 30 is sealed between the housing 10 and the cover plate 20. This integrally connected gas sensor has high sensitivity and excellent sealing performance.

[0040] Furthermore, in some specific embodiments, both the housing 10 and the cover plate 20 are made of metal, and the housing 10 and the cover plate 20 are integrally connected by laser welding without the need for additional snap-fit ​​structures, thus reliably sealing the entire waterproof and breathable membrane 30. In another specific embodiment, both the housing 10 and the cover plate 20 are made of plastic, and the housing 10 and the cover plate 20 are integrally connected by ultrasonic welding, again without the need for additional snap-fit ​​structures, thus reliably fixing the entire waterproof and breathable membrane 30. When there is a need for high temperature resistance in practical applications, the housing 10 and the cover plate 20 are made of metal, and the welding process uses laser welding. When the housing 10 and the cover plate 20 are made of plastic, the inner cavity 11 of the housing 10 needs to be polished and then gold-plated. This is to ensure that the infrared light is completely reflected within the air chamber 60, preventing infrared light scattering that could lead to inaccurate detection.

[0041] Based on the above embodiments, the gas sensor of the present invention, due to its excellent waterproof and sealing performance, can be applied to air conditioning systems, new energy vehicle thermal management systems, automated detection systems, automotive braking systems, etc.

[0042] In summary, the gas sensor of the present invention has the following advantages:

[0043] (1) The gas sensor is provided with a second through hole 21, a waterproof and breathable membrane 30 and a first through hole 13 from the outside to the inside, which effectively prevents liquid from entering the sensor and affecting the measurement results.

[0044] (2) The shell 10 and the cover plate 20 are welded together in one piece, which securely fixes the entire waterproof and breathable membrane 30 without the need for additional buckle structure. It is aesthetically pleasing, improves sealing performance and reduces leakage rate, and has a fast response time and high sensitivity.

[0045] (3) The waterproof and breathable membrane 30 is not easy to fall off and can be used in water for a long time without cracking, effectively extending the service life of the infrared sensor and thus making the waterproof performance better.

[0046] (4) By setting the size and direction of the first through hole 131 and the second through hole 211, the gas can enter the gas chamber 60 evenly and has a high accuracy.

[0047] The above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described in the present invention. The understanding of this specification should be based on those skilled in the art. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still make modifications or equivalent substitutions to the present invention. All technical solutions and improvements that do not depart from the spirit and scope of the present invention should be covered within the scope of the claims of the present invention.

Claims

1. A gas sensor, characterized in that: The gas sensor includes a housing, a cover plate, and a waterproof and breathable membrane. The housing has an inner cavity and a side wall located around the inner cavity. The side wall has a first through hole, which penetrates the side wall and provides gaseous communication between the inner cavity and the outside of the housing. The cover plate is welded to the side wall, and the cover plate has a second through hole, the second through hole including a second through hole penetrating the cover plate; At least a portion of the waterproof and breathable membrane is located between the first through-hole portion and the second through-hole portion; The cover plate includes a filter screen portion and a connecting portion. The second through hole portion is disposed in the filter screen portion. The connecting portion is located on the periphery of the filter screen portion. The filter screen portion is away from the side wall relative to the connecting portion. The connecting portion is connected to the side wall. The connecting portion is located on the periphery of the waterproof and breathable membrane. The sidewall is provided with a groove, at least a portion of the cover plate is located within the groove, and the outer surface of the filter part is flush with the outer surface of the sidewall surrounding the groove.

2. The gas sensor according to claim 1, characterized in that: The housing includes a first wall surface located around the first through hole. Along the extending direction of the first through hole, the projection of the first wall surface onto the cover plate is within the outer contour of the cover plate, and the projection of the first wall surface onto the waterproof and breathable membrane is within the outer contour of the waterproof and breathable membrane.

3. The gas sensor according to claim 1, characterized in that: The filter section is connected to the connecting section.

4. The gas sensor according to claim 1, characterized in that: The sidewall includes a first sidewall and a second sidewall. Along a direction perpendicular to the length of the housing, the first sidewall and the second sidewall are located on both sides of the inner cavity, and both the first sidewall and the second sidewall are provided with a first through hole.

5. The gas sensor according to claim 1, characterized in that: The groove is formed by recessing from the outer surface of the housing into the interior of the housing, and the first through hole is located between the groove and the inner cavity.

6. The gas sensor according to claim 1, characterized in that: The cover plate is welded to the outer surface of the sidewall.

7. The gas sensor according to claim 1, characterized in that: There are multiple second through holes, and the inner diameter of the second through hole is smaller than the inner diameter of the first through hole.

8. The gas sensor according to claim 1, characterized in that: There are at least two first through holes, and the at least two first through holes extend in the same direction; there are at least two second through holes, and the at least two second through holes extend in the same direction.

9. The gas sensor according to claim 1, characterized in that: The extension direction of the first through hole is the same as the extension direction of the second through hole.

10. The gas sensor according to claim 1, characterized in that: It also includes a light source, a detector, and a circuit board. The light source and the detector are both electrically connected to the circuit board. At least a portion of the light source and the detector are located on the periphery of the inner cavity. Along the length of the housing, the light source and the detector are located at opposite ends of the housing.

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