A gas detection device and a gas detector thereof

Abstract

The disclosure discloses a gas detection device and a gas detector thereof, which comprises: a light source for emitting composite light; a light splitting piece for splitting the composite light beam emitted by the light source into a first light beam and a second light beam; a containing piece comprising a detection cavity for containing a gas to be detected and receiving the first light beam and the second light beam, and the inner wall of the containing piece is provided with a reflecting part for reflecting the first light beam and the second light beam in the detection cavity, and the light path shape of the first light beam and the second light beam in the detection cavity is symmetrical; and a detection piece comprising a first channel and a second channel, wherein the first light beam and the second light beam enter the first channel and the second channel respectively for detection after being reflected. According to the scheme, the detection light paths of the first and second light beams used for detection are equal by setting the light splitting piece and the containing piece with the reflecting part, and the detection error is reduced.

Description

Technical Field

[0001] This disclosure generally relates to the field of gas detection technology. More specifically, this disclosure relates to a gas detection device and its gas detector. Background Technology

[0002] In existing technologies, gas detection devices utilizing the principle of free diffusion in air typically struggle to achieve a large optical path within a small volume while simultaneously maintaining a high light energy collection rate. In most applications, gas detection devices incorporate a dual-channel gas sensor. To suppress signal drift caused by factors such as optical chamber contamination, light source attenuation, and extreme temperature variations, the optical path of the dual-channel detector must process the light beam into two highly consistent beams. However, current technologies cannot ensure that these two beams maintain this high degree of consistency upon reaching the detector. This results in significant detection errors and low resistance to external interference in existing gas detection devices.

[0003] In view of this, there is an urgent need to provide a gas detection device solution that can improve the reliability of the detection device while increasing the detection optical path. Summary of the Invention

[0004] In order to at least solve one or more of the technical problems mentioned above, this disclosure proposes a gas detection device and a gas detector thereof in the following aspects.

[0005] In a first aspect, this disclosure provides a gas detection device, comprising: a light source for emitting composite light; a beam splitter for dividing the composite light beam emitted by the light source into a first beam and a second beam; a accommodating member including a detection cavity for accommodating a gas to be tested and receiving the first beam and the second beam, wherein the inner wall of the accommodating member is provided with a reflective portion for reflecting the first beam and the second beam in the detection cavity, and the optical path shapes of the first beam and the second beam in the detection cavity are symmetrical; and a detection member including a first channel and a second channel, wherein the first beam and the second beam, after reflection, respectively enter the first channel and the second channel for detection.

[0006] In some embodiments, the shape of the reflector is mirror-symmetrical on both sides, and the beam splitter directs the first beam and the second beam symmetrically toward both sides of the reflector.

[0007] In some embodiments, the beam splitter is used to direct the first beam and the second beam in two opposite directions.

[0008] In some embodiments, the beam splitter has two reflective surfaces that are angled at 90°.

[0009] In some embodiments, the reflective portion includes a first reflector and a second reflector, as well as a third reflector and a fourth reflector that are mirror-symmetrical to the first reflector and mirror-symmetrical to the second reflector. The first reflector is used to reflect a first light beam toward the second reflector, the second reflector is used to reflect the first light beam toward the third reflector, and the third reflector is used to reflect the first light beam toward the direction of the detection element.

[0010] In some embodiments, a fifth reflector is further included, which is used to reflect the first light beam reflected by the third reflector to the first channel and to reflect the second light beam reflected by the first reflector to the second channel.

[0011] In some embodiments, the fifth reflector has a focusing surface.

[0012] In some embodiments, the detection element further includes a first filter and a second filter, the first filter being disposed in the first channel to filter out light of a first wavelength entering the first channel, and the second filter being disposed in the second channel to filter out light of a second wavelength entering the second channel.

[0013] In some embodiments, a light-blocking element is also included, which is disposed between the light source and the detection element along the optical path.

[0014] In a second aspect, this disclosure provides a gas detector, comprising: a gas detection device according to the first aspect and several embodiments; a base, a light source and a detection element disposed on the base; a protective member, one side of which is connected to the base to form an inner cavity for accommodating the gas detection device, and the protective member is further provided with a vent hole communicating with the detection cavity of the gas detection device.

[0015] By using the gas detection device provided above, the embodiments disclosed herein, through the inclusion of a beam splitter and a receiving member with a reflective portion, can form a longer optical path within a limited volume, and make the detection optical path shapes of the first and second beams used for detection symmetrical, thereby reducing detection errors. Furthermore, in some embodiments, by providing mirror-symmetrical reflective portions, the optical paths of the first and second beams can be arranged intersectingly, making the device more compact. Even further, in some embodiments, by providing a light-blocking member, the influence of stray light on detection accuracy can be reduced. Attached Figure Description

[0016] The above and other objects, features, and advantages of exemplary embodiments of this disclosure will become readily apparent upon reading the following detailed description with reference to the accompanying drawings. In the drawings, several embodiments of this disclosure are illustrated by way of example and not limitation, and like or corresponding reference numerals denote like or corresponding parts, wherein:

[0017] Figure 1 A perspective schematic diagram of a gas detection device according to some embodiments of this disclosure is shown;

[0018] Figure 2 An exploded schematic diagram of a gas detection device according to some embodiments of this disclosure is shown;

[0019] Figure 3 A perspective view of the upper housing of a gas detection device according to some embodiments of this disclosure is shown;

[0020] Figure 4 A cross-sectional schematic diagram of a gas detection device according to some embodiments of this disclosure is shown;

[0021] Figure 5 A schematic diagram of the internal optical path of the detection cavity of a gas detection device according to some embodiments of this disclosure is shown;

[0022] Figure 6 A schematic diagram of the internal optical path of the detection cavity of a gas detection device according to some embodiments of this disclosure is shown;

[0023] Figure 7 An exploded schematic diagram of a gas detector according to some embodiments of this disclosure is shown. Detailed Implementation

[0024] The technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this disclosure, not all of them. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0025] It should be understood that the terms “comprising” and “including” used in this disclosure and claims indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0026] It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of this disclosure. As used in this disclosure and claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used in this disclosure and claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes such combinations.

[0027] As used in this specification and claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if [described condition or event] is detected" may be interpreted, depending on the context, as "once determined," "in response to determination," "once [described condition or event] is detected," or "in response to detection of [described condition or event]."

[0028] The specific embodiments disclosed herein will now be described in detail with reference to the accompanying drawings.

[0029] This disclosure provides a gas detection scheme that minimizes the influence of external factors on the measurement beam by having the first and second beams enter the detection channel through symmetrical optical paths.

[0030] First see Figure 1 and Figure 2 , Figure 1 A perspective schematic diagram of a gas detection device according to some embodiments of this disclosure is shown. Figure 2 An exploded view of a gas detection device according to some embodiments of this disclosure is shown. In some embodiments, the gas detection device 100 may include an upper housing 101 and a lower housing 102, which are assembled relative to each other to form a receiving member, thereby defining a detection chamber for containing gas within the receiving member. The detection chamber is used to introduce the gas to be detected, and a light source 20 and a detection element 30 are simultaneously disposed within the detection chamber. The light source 20 may be a light source capable of emitting composite light, and the detection element 30 may be a dual-channel detection element 30 including a first channel 31 and a second channel 33. See also... Figure 3 , Figure 3 A perspective view of the upper housing of a gas detection device according to some embodiments of this disclosure is shown. In some embodiments, a beam splitter 11 may be provided on one side of the inner end face of the upper housing 101 of the accommodating member. The beam splitter 11 is positioned opposite to the light source 20 to evenly divide the light emitted by the light source 20 into a first beam 110 and a second beam 120. A reflective portion may be provided on the circumferential side inside the upper housing 101. The reflective portion is used to reflect the first beam 110 and the second beam 120, which are evenly divided by the beam splitter 11, in the detection cavity. The optical path shapes of the first beam 110 and the second beam 120 in the detection cavity are symmetrical. After reflection, the first beam 110 and the second beam 120 can enter the first channel 31 and the second channel 33 respectively for detection.

[0031] Specifically, in some embodiments, the upper housing 101 may be generally hollow cylindrical, and the lower housing 102 may be generally cylindrical. One axial end of the upper housing 101 is open to coaxially engage with the lower housing 102. The other axial end of the upper housing 101 is provided with a vent 12, which communicates with its internal detection chamber for introducing the gas to be tested into the detection chamber for detection. The lower housing 102 may be provided with a detection element mounting hole 22 and a light source mounting hole 21. The detection element 30 and the light source 20 are respectively installed in the corresponding mounting holes on the lower housing 102, such that the light-emitting part of the light source 20 and the inlet of the first channel 31 and the second channel 33 of the detection element 30 are oriented towards the upper housing 101 and exposed in the detection chamber along the axial direction of the upper housing 101. In some embodiments, the light source 20 and the detection element 30 are both located at the centerline of the lower housing 102, that is, the line connecting their respective centers coincides with the center of the axial end face of the lower housing 102, and the entrances of the first channel 31 and the second channel 33 of the detection element 30 are symmetrical with respect to the centerline. A focusing slope 23 can also be provided on the side of the light source mounting hole 21 facing the upper housing 101. This focusing slope 23 can be, for example, generally a cone shape open towards the upper housing 101. The focusing slope 23 can be a reflective surface such as a mirror, so that the light emitted from the side of the light source 20 can be reflected by the focusing slope 23 and emitted towards the beam splitter 11, forming a collimated beam with a consistent direction and reducing stray light emitted in other directions.

[0032] The beam splitter 11 is disposed on the axial end face inside the upper housing 101. It is approximately a cone with an isosceles right-angled triangle cross-section. Its right-angled edge protrudes along the axial direction of the upper housing 101 towards the lower housing 102. The position of the right-angled edge corresponds to the centerline of the axial end face of the upper housing 101, that is, the inclined surfaces corresponding to the two right-angled edges are mirror-symmetrical with respect to the centerline of the axial end face of the upper housing 101. The central axis of the light-emitting part of the light source 20 can be aligned with the edge of the right-angled edge of the beam splitter 11 in the axial direction of the upper housing 101. Here, the plane formed by the central axis of the light source 20 and the edge of the right-angled edge of the beam splitter 11 can be defined as the beam splitting plane. Then, the light emitted by the light-emitting part of the light source 20 located on both sides of the beam splitting plane can evenly illuminate the inclined surfaces corresponding to the two right-angled edges of the beam splitter 11. The two equal right-angled sides of the beam splitter 11 can be configured as reflective surfaces such as mirrors, so that the light from the light source 20 illuminating these two reflective surfaces along the axial direction of the upper housing 101 is equally divided into two beams, namely the first beam 110 and the second beam 120. Furthermore, since these two reflective surfaces are the sides corresponding to the two right-angled sides of the beam splitter 11, i.e., the angle between the two reflective surfaces is 90°, and the angle between each reflective surface and the beam splitting plane is 45°, this causes the first beam 110 and the second beam 120 to be reflected by the two reflective surfaces to the lateral sides perpendicular to the axial direction of the upper housing 101, respectively.

[0033] In some embodiments, the reflective portion inside the upper housing 101 includes a plurality of reflective elements disposed on the inner circumferential wall of the upper housing 101, wherein the plurality of reflective elements are arranged in a mirror-symmetric manner with respect to both sides of the aforementioned beam-splitting plane. For example, the reflective portion may include five reflective elements disposed on the inner circumferential wall, namely a first reflective element 13 and a second reflective element 15 located on the first side of the beam-splitting plane, a third reflective element 17 and a fourth reflective element 19 located on the second side of the beam-splitting plane, and a fifth reflective element 18 located at a position corresponding to the detection element 30. The first reflective element 13 and the third reflective element 17 are mirror-symmetric with respect to both sides of the beam-splitting plane, the second reflective element 15 and the fourth reflective element 19 are mirror-symmetric with respect to the beam-splitting plane, and the fifth reflective element 18 itself is divided into two parts, which are respectively located on both sides of the beam-splitting plane and are mirror-symmetric about the beam-splitting plane. The mirror symmetry mentioned here means that the shape, orientation, size, etc. of the reflective portion of the reflective element are mirror-symmetric with respect to the beam-splitting plane. This configuration ensures that the two optical paths formed by the first beam 110 and the second beam 120 after reflection by the reflector inside the detection cavity are mirror-symmetrical, guaranteeing that the first beam 110 and the second beam 120 have the same angle after passing through the detection cavity, thus reducing test errors.

[0034] The specific optical paths of the first beam 110 and the second beam 120 within the detection cavity are described below with reference to the accompanying drawings. (See attached figures) Figure 5 , Figure 5 A schematic diagram of the internal optical path of the detection cavity of a gas detection device according to some embodiments of this disclosure is shown, wherein... Figure 5The arrows in the diagram indicate exemplary optical paths of a portion of the light rays in the first beam 110 or the second beam 120. In some embodiments, the reflective surface of the first reflector 13 extends axially along the upper housing 101 and includes a first reflective surface forming a first angle with the beam-splitting plane. The position of the first reflector 13 is aligned with the beam-splitting element 11, such that the first beam 110 reflected by the beam-splitting element 11 can illuminate the first reflective surface of the first reflector 13. Similarly, the reflective surface of the second reflector 15 also extends axially along the upper housing 101 and includes a second reflective surface forming a second angle with the beam-splitting plane. However, the tilt direction of the second reflector 15 is opposite to that of the first reflector 13, and its position is opposite to that of the first reflector 13, such that the first beam 110 reflected by the first reflective surface of the first reflector 13 can illuminate the second reflector 15 and be further reflected by the second reflective surface. Furthermore, since the first reflector 13 and the third reflector 17 are symmetrical with respect to the beam-splitting plane, and the second reflector 15 and the fourth reflector 19 are symmetrical with respect to the beam-splitting plane, the arrangement of the third reflector 17 and the fourth reflector 19 is similar to that of the first reflector 13 and the second reflector 15. This configuration makes the first reflector 13 and the third reflector 17, and the second reflector 15 and the fourth reflector 19, face each other in a direction perpendicular to the beam-splitting plane, with opposite tilt angles. By setting the angle of the second reflective surface, the first beam 110 reflected by the second reflective surface can be reflected to the third reflective surface of the third reflector 17, and further reflected by the third reflective surface of the third reflector 17 to the fifth reflector 18. In some embodiments, the fifth reflector 18 is configured to have a focusing surface, which faces both the axial direction of the upper housing 101 and the direction of the detection element 30. The first beam 110 reflected by the third reflector 17 is focused by the focusing surface and simultaneously reflected to the first channel 31 of the detection element 30, and thus enters the channel to complete the detection. Meanwhile, since the overall structure of the reflector is mirror-symmetrical about both sides of the beam splitting plane, the light path of the second beam 120 in the detection cavity after being reflected by the beam splitter is also mirror-symmetrical about the beam splitting plane with the light path of the first beam 110. The irradiation sequence is from the beam splitter 11 to the third reflector 17, from the third reflector 17 to the fourth reflector 19, from the fourth reflector 19 to the first reflector 13, from the first reflector 13 to the fifth reflector 18, and finally converged and reflected by the focusing surface of the fifth reflector 18 to the second channel 33 of the detection element 30 for detection.

[0035] In some embodiments, the first and second reflecting surfaces of the first reflector 13 and the second reflector 15 can be generally curved. Their specific shapes can be determined according to the direction and intensity distribution of the first beam 110 and the second beam 120 reflected by the beam splitter 11, aiming to converge the first beam 110 or the second beam 120 as much as possible and accurately reflect it to the second reflector 15 and the third reflector 17, thereby maximizing the light collection rate. Similarly, the reflecting surfaces of the third reflector 17 and the fourth reflector 19 can also be generally curved to converge and accurately reflect the corresponding beams. It is understood that in some implementation scenarios, such as when the collimation of the light from the light source 20 is strong, the reflecting surfaces of the aforementioned multiple reflectors, including the fifth reflector 18, can also be formed as planes, or spliced ​​together from multiple inclined surfaces with different tilt angles to reduce processing costs.

[0036] In some embodiments, by setting the shapes of the first reflector 13, the second reflector 15, the third reflector 17, the fourth reflector 19, and the fifth reflector 18, the reflective surfaces on each reflector can be adjusted according to the light emission direction of the beam splitter 11 to form a reflective surface with curvature or angle. By adjusting the angle or curvature of the reflective surface, the specific position of light irradiation and reflection on the reflective surface of each reflector at each reflection node in the entire optical path can be adjusted, so that more than 50% of the total area of ​​the reflective surface within the accommodating component participates in effective reflection. The reflective surface set here can include regular curved surfaces such as cylindrical surfaces, spherical surfaces, and parabolic surfaces, or combinations of several such surfaces. Furthermore, part of the curved surface of the reflective surface can be processed using CPC composite parabolic focusing technology, resulting in a strong constraint ability of the reflective surface on the light emitted from the light source and a high effective light conversion rate. The reflective surfaces of the aforementioned reflective elements can be high-brightness mirrors, formed by coating with a reflective film. The coating or forming material includes, but is not limited to, 24K gold, K gold, aluminum with silicon dioxide, etc., giving the reflective surfaces of each element oxidation and salt spray resistance. Furthermore, the aforementioned reflective surfaces can also specifically possess characteristics of high reflectivity, low absorptivity, and good stability for light within the wavelength range that hydrocarbons can absorb.

[0037] As can be seen, by setting up a perfectly mirror-symmetrical reflector, the light rays divided into two equal parts have completely mirror-image paths within the detection cavity, with identical path distances and opposite angles of entry into the detection channel. This ensures the best similarity between the first and second beams 120 at the detection end, greatly reducing experimental errors caused by unequal light paths and improving measurement accuracy. Furthermore, since the first beam 110 and the second beam 120 share a portion of the reflector in this configuration, their light paths intersect, effectively reducing the number of reflectors required to extend the optical path without affecting detection accuracy. This results in a lower cost, fewer error-causing factors, and a more compact structure, making it suitable for working conditions with limited measurement space.

[0038] In this embodiment, a first filter plate and a second filter plate are respectively provided on the first channel 31 and the second channel 33. The first filter plate and the second filter plate are used to filter the light irradiated to the entrance of the corresponding channel. For example, the first filter plate is used to filter out light other than the first wavelength, and the second filter plate is used to filter out light other than the second wavelength. Since the light emitted by the light source 20 is composite light, that is, it includes light with at least two wavelengths, two filters can be provided to filter the light of the two wavelengths separately. For example, for the first channel 31, the first wavelength light and the second wavelength light contained in the measurement beam are affected by the first filter. The former is transmitted through the filter and passes through the first channel 31 without changing direction, reaching the photosensitive chip built into the detection element 30 to generate a first electrical signal. The latter is reflected by the first filter, changes direction to the inner end face of the upper housing 101, and forms an inactive light beam until its energy is exhausted during the reflection process. Similarly, for the second channel 33, the first wavelength light it contains can be filtered out by the second filter and reflected to the inner end face of the upper housing 101 until the reflection is exhausted, while the second wavelength light it contains can pass through the second filter and enter the second channel 33, reaching the photosensitive chip corresponding to the second channel 33 to generate a second electrical signal. By receiving and comparing the intensities of the first and second electrical signals, the concentration of the gas to be detected can be detected. For example, when detecting methane gas, when methane gas present in the outside enters the detection chamber through free diffusion, the light of the first wavelength contained in the first beam 110, corresponding to the absorption spectrum line of the gas to be detected, will be absorbed by the gas. The higher the gas concentration, the greater the amount of light absorbed, so that the light intensity reaching the first channel 31 in the detection element 30 becomes correspondingly weaker. This makes the first electrical signal converted from the light intensity by the detection chip in the detection element 30 also correspondingly weaker, and the intensity of the weakened first electrical signal can indicate the level of gas concentration. Simultaneously, the second wavelength of light in the second beam 120 will not be absorbed by the gas to be tested, and the light intensity reaching the second channel 33 in the detector remains unchanged. The intensity of the second signal converted by the monitoring chip in the detection element 30 also remains unchanged, proving that the detection device is functioning normally. The aforementioned reflective element provides a high optical path length, resulting in high resolution accuracy. Specifically, by setting a beam-splitting surface to equally divide the first beam 110 and the second beam 120, when the gas detection device 100 is subjected to external contamination or other influences, the light received by the first channel 31 and the second channel 33 will increase or decrease proportionally. This ensures that external influences will not disrupt the original numerical ratio of the electrical signals generated by the two channels, thereby providing anti-contamination protection and improving the reliability of the device.

[0039] Simultaneously refer to Figure 4 , Figure 4A cross-sectional schematic diagram of a gas detection apparatus according to some embodiments of this disclosure is shown. In some embodiments, a light-blocking member is provided on the side of the beam splitter 11 facing the detection element 30. This light-blocking member is used to block the lateral light emitted by the light source 20 directly toward the detection element 30. Since this lateral light does not undergo multiple reflections through multiple reflectors as described in some embodiments to extend the light path, it will not be fully absorbed in the detected gas, and its actual irradiation direction has not been converged and corrected by multiple reflectors. When it enters the detection element 30, its irradiation direction cannot be determined, and it may enter any detection channel, thereby greatly increasing the detection error. To address this, the light-blocking member is provided on the side of the beam splitter 11, extending along the axial direction of the upper housing 101 and close to the upper surface of the lower housing 102. It also extends beyond the lateral sides of the beam splitter 11 in a lateral direction perpendicular to the beam splitting plane, thereby minimizing the entry of the lateral light from the light source 20 into the detection cavity. Additionally, a first auxiliary surface and a second auxiliary surface can be provided on the side of the light-blocking member facing away from the beam splitter 11. These first and second auxiliary surfaces can be two inclined surfaces symmetrically arranged relative to the beam splitter plane, which can be used to further guide the optical path inside the detection cavity or to eliminate light rays deviating from the optical path. For example, the first and second auxiliary surfaces can be reflective surfaces such as mirrors, thus forming part of the reflective portion of the upper housing 101. By setting the angle of other reflective elements in the reflective portion, the detection beam can be further lengthened by reflection from the first and second auxiliary surfaces. Furthermore, in some implementation scenarios, the first and second auxiliary surfaces can also be set as light-absorbing surfaces. For example, matte treatment or light-absorbing coatings can be used to make the first and second auxiliary surfaces absorb light. By setting the shape and position of the first and second auxiliary surfaces, light rays irradiated to undesirable locations can be absorbed and eliminated, thereby further improving detection accuracy.

[0040] Those skilled in the art will understand that the configuration of the first reflector 13, the second reflector 15, the third reflector 17, the fourth reflector 19, and the fifth reflector 18 in the above embodiments are merely exemplary configurations. This disclosure does not specifically limit the shape, type, or number of the reflectors in the reflective section. For example, more reflectors can be provided to extend the optical path distance, or lenses or other optical devices can be provided to further converge the beam or precisely control the direction of the light, as long as each optical device in the reflective section can ensure that the first beam 110 and the second beam 120 passing through the detection cavity can pass through an equivalent optical path. The equivalent optical path referred to here means that the beams travel equal distances in the optical path, the light energy attenuation caused by the reflectors or transmissors is equal, and the final exit angles are equal or opposite, thereby ensuring that the final detection yields minimal error between the two beams. In addition, although some of the above embodiments describe a scheme using a protruding structure with a right-angled triangular cross section as the beam splitter 11, this disclosure does not limit the specific form of the beam splitter 11. For example, it can be set as lenses of the same shape and size respectively provided on both sides of the light source 20 in the lateral direction, so that the light emitted from both sides of the light source 20 can be refracted by the two equal lenses in two different directions to form a first beam 110 and a second beam 120.

[0041] See Figure 6 , Figure 6 A schematic diagram of the internal optical path of the detection cavity of a gas detection device according to some embodiments of this disclosure is shown. In some embodiments, a light-blocking element may be omitted, allowing the light emitted by the light source 20 to directly illuminate the beam splitter 11. In this embodiment, the structure of the detection device is simpler, and due to the reduction of the obstruction by the light-blocking element, the range of angles traversed by the optical path within the detection cavity is larger. With the same optical path distance, the structure of the detection device can be made more compact. Furthermore, in this embodiment, by adjusting the size of the light source mounting hole 21 in the lower housing 102, the light-emitting portion of the light source 20 can be further embedded in the light source mounting hole 21, thus limiting the light emitted by the light source 20 by the light source mounting hole 21 and preventing laterally exposed light from entering the optical path and affecting the detection results.

[0042] Those skilled in the art will understand that although the embodiments described in this disclosure depict a technical solution of configuring the receiving member with a mirror-symmetrical reflective portion, this disclosure does not limit the specific arrangement of the reflective portion. The specific structure and arrangement of the reflective portion shall be based on its ability to ensure that the reflection of the first and second beams 120 in the detection cavity can pass through an equivalent optical path. For example, the beam splitter 11 can be replaced with a horizontally arranged partition plate, and the detection member 30 can also be changed to a horizontally arranged partition plate, so that the first and second beams 120 separated by the beam splitter 11 can be reflected independently by the reflective portion and enter the corresponding detection channel through the same optical path, etc.

[0043] By incorporating a beam splitter and a reflective housing, the gas detection apparatus 100 according to the embodiments of this disclosure effectively increases the detection optical path. Furthermore, by ensuring that the first and second beams follow equivalent optical paths, the influence of external conditions on the measured values ​​is minimized, resulting in stronger anti-interference and anti-contamination capabilities. The increased measurement resolution achieved through the extended optical path can, for example, satisfy the identification of methane gas among HC gases. Further, by configuring a mirror-symmetric optical path, a passive anti-contamination and attenuation structure is formed, effectively eliminating detection inaccuracies caused by fine impurities and light source attenuation. The embodiments described above in this disclosure achieve an effective optical path several times greater than most prior art products within a limited volume without sacrificing light utilization, and structurally implement anti-interference and attenuation functions. This results in extremely low electrical signal noise, high detection sensitivity, and long-term stability under various operating conditions, leading to higher measurement accuracy.

[0044] See Figure 7 , Figure 7An exploded view of a gas detector according to some embodiments of this disclosure is shown. A detector for detecting gas may include a gas detection device 100 as described in some embodiments of this disclosure. The gas detector has a generally hollow cylindrical protective member 50, one end of which is open and engages with a base plate 40. The protective member 50 and the base plate together define an accommodating space for accommodating the gas detection device 100. The other end of the protective member 50 is provided with a detection opening 52, which may be, for example, an axially open opening for allowing the gas to be detected to pass into the interior for detection by the gas detection device 100. In this embodiment, a filter may also be provided at the detection opening 52 to filter the gas to be detected. The filter may include, for example, a filter screen 51 and a filter membrane 53. The filter screen 51 may be, for example, a sintered steel mesh, used to filter larger particulate impurities and located on the outer layer of the filter membrane 53. The filter membrane 53 may be, for example, a waterproof and breathable membrane for filtering fine particulate impurities. The filter screen 51 and filter membrane 53 can be stacked and cover the outside of the vent 12 of the upper housing 101 of the gas detection device 100. A positioning groove can be provided on the outer end face of the upper housing 101 in the axial direction. This positioning groove matches the shape of the filter screen 51 and filter membrane 53, allowing them to be positioned within the groove and preventing displacement that could lead to filtration failure. The edge of the detection opening 52 of the protective member 50 can be used to abut against the filter screen 51 axially. That is, the diameter of the detection opening 52 is smaller than the outer diameter of the filter screen 51. After the protective member 50 is joined to the base plate 40, the edge of the detection opening 52 abuts against the outer periphery of the filter screen 51 on the inner side of the protective member 50, thus securing it against the upper housing 101 of the gas detection device 100. The upper housing 101 and lower housing 102 are fixed relative to each other by means of a mounting member 55. The base plate 40 can be provided with multiple wire holes. The connection ends of the light source 20 and the detection element 30 of the gas detection device 100 can be connected to the electronic control module 41 through the wire holes on the base plate 40. The electronic control module 41 can be further connected to external equipment through the connector 43 at its bottom. The electronic control module 41 is used to supply power to the light source 20 and the detection element 30, control the switching of the light source 20 and the detection element 30, and transmit detection parameters, etc. The part of the module with the electronic control components is arranged facing the base plate 40, and it can be isolated from the base plate 40 by potting glue to achieve a fully sealed and insulated treatment.

[0045] While numerous embodiments of this disclosure have been shown and described herein, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Many modifications, alterations, and alternatives will occur to those skilled in the art without departing from the spirit and intent of this disclosure. It should be understood that various alternatives to the embodiments of this disclosure described herein may be employed in the practice of this disclosure. The appended claims are intended to define the scope of this disclosure and therefore cover equivalents or alternatives within the scope of these claims.

Claims

1. A gas detection device, characterized in that, include: Light source (20), which is used to emit composite light; A beam splitter (11) is used to split the composite light beam emitted by the light source (20) into a first beam and a second beam. The accommodating member (10) includes a detection cavity for accommodating the gas to be tested and receiving a first light beam and a second light beam, and the inner wall of the accommodating member (10) is provided with a reflective part, which is used to reflect the first light beam and the second light beam in the detection cavity, and the light path shapes of the first light beam and the second light beam in the detection cavity are symmetrical. The detection component (30) includes a first channel (31) and a second channel (33). The first beam and the second beam are reflected and then enter the first channel (31) and the second channel (33) respectively for detection. The reflective part includes a first reflector (13) and a second reflector (15), as well as a third reflector (17) mirror-symmetrical to the first reflector (13) and a fourth reflector (19) mirror-symmetrical to the second reflector (15). The first reflector (13) is used to reflect the first light beam toward the second reflector (15), the second reflector (15) is used to reflect the first light beam toward the third reflector (17), the third reflector (17) is used to reflect the first light beam toward the detection element (30), and the third reflector (17) is also used to reflect the second light beam toward the fourth reflector (19), the fourth reflector (19) is used to reflect the second light beam toward the first reflector (13), and the first reflector (13) is used to reflect the second light beam toward the detection element (30). It also includes a fifth reflector (18) for reflecting the first light beam reflected by the third reflector (17) to the first channel (31) and reflecting the second light beam reflected by the first reflector (13) to the second channel (33).

2. The gas detection device according to claim 1, characterized in that, The shape of the reflective part is mirror symmetrical on both sides, and the beam splitter (11) causes the first beam and the second beam to be directed symmetrically to both sides of the reflective part.

3. The gas detection device according to claim 2, characterized in that, The beam splitter (11) is used to shoot the first beam and the second beam in two opposite directions respectively.

4. The gas detection device according to claim 3, characterized in that, The beam splitter (11) has two reflective surfaces that are angled at 90°.

5. The gas detection device according to claim 1, characterized in that, The fifth reflector (18) has a light-concentrating curved surface.

6. The gas detection device according to claim 1, characterized in that, The detection element (30) further includes a first filter (35) and a second filter (37). The first filter (35) is disposed in the first channel (31) to filter out light of the first wavelength entering the first channel (31), and the second filter (37) is disposed in the second channel (33) to filter out light of the second wavelength entering the second channel (33).

7. The gas detection device according to any one of claims 1-6, characterized in that, It also includes a light-blocking element (16), which is disposed along the optical path between the light source (20) and the detection element (30).

8. A gas detector, characterized in that, include: Gas detection device according to any one of claims 1-7; The base (40), the light source (20) and the detection element (30) are disposed on the base (40); The protective component (50) is connected to the base (40) on one side to form an inner cavity for accommodating the gas detection device, and the protective component (50) is also provided with a vent hole that communicates with the detection cavity of the gas detection device.

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