Combustible gas detection device

Abstract

The utility model discloses a combustible gas detection device. The combustible gas detection device comprises a laser emitting system, a laser receiving system, a gas container and a control circuit, the laser emitting system is used for emitting laser beams; the laser receiving system is used for receiving the laser beams; the gas container is at least partially arranged on a propagation path of the laser beam, the laser beam can penetrate through the gas container, the gas container is provided with a closed cavity, and the cavity is filled with target gas with known concentration; the control circuit is electrically connected with the laser receiving system and determines the measured concentration of the target gas, the measured concentration is the sum of the concentrations of the target gas inside and outside the gas container, and the control circuit uses the concentration of the target gas in the cavity as the reference concentration; and determining the actual concentration of the target gas outside the gas container according to the difference between the measured concentration and the reference concentration. Through the arrangement, the detection precision of the target gas is ensured, and meanwhile, the overall size of the combustible gas detection device is smaller, so that the combustible gas detection device is convenient to use in a family environment.

Description

Technical Field

[0001] This application relates to the field of gas concentration monitoring technology, and in particular to a combustible gas detection device. Background Technology

[0002] Because household combustible gas detectors are generally small in size, the laser sensors also need to be miniaturized. To reduce the size of the laser sensors, manufacturers minimize the distance between the laser and the detector to meet the requirements of miniaturization. However, this results in a drawback: the laser sensors are poor at measuring low concentrations of target gases. For example, currently available miniaturized household combustible gas laser sensors are basically unable to detect methane leaks at concentrations of 3% LEL or lower in the air, meaning the output concentration measurement result is 0% LEL. The root cause of this result is that the optical path between the laser transmitter and receiver is too short.

[0003] Household combustible gas laser sensors cannot detect methane gas leaks at concentrations of 3% LEL or below in the air. This means they cannot detect trace amounts of natural gas leaks in the kitchen. In the long run, this will not only cause gas losses for users, but also harm their health due to prolonged exposure to such a leaky environment, and increase potential safety hazards.

[0004] Although the manufacturer has tried to reduce the size as much as possible while ensuring measurement accuracy, the size is still slightly large. From an application perspective, it is still desirable to further reduce the size. Utility Model Content

[0005] To address the shortcomings of existing technologies, the purpose of this application is to provide a combustible gas detection device with high detection accuracy and a small overall size.

[0006] To achieve the above objectives, this application adopts the following technical solution:

[0007] This application provides a combustible gas detection device, which includes a housing and a circuit board. The housing has at least one vent hole, and the interior of the housing communicates with the external environment through the vent hole. The circuit board is fixedly disposed inside the housing. The combustible gas detection device also includes a laser emitting system, a laser receiving system, a gas container, and a control circuit. The laser emitting system is used to emit a laser beam. The gas container is at least partially disposed in the propagation path of the laser beam and allows the laser beam to pass through. The gas container has a closed cavity filled with a target gas of known concentration. The gas container is detachably mounted on the circuit board, and different target gases can be detected by replacing the gas container filled with different target gases. The laser receiving system is used to receive the laser beam passing through the gas container and generate an electrical signal based on the received laser beam. The control circuit is electrically connected to the laser receiving system. The control circuit determines the concentration of the target gas interacting with the laser beam based on the electrical signal, as a measured concentration. The control circuit stores the concentration of the target gas in the cavity as a reference concentration. The control circuit determines the actual concentration of the target gas in the environment based on the difference between the measured concentration and the reference concentration.

[0008] Furthermore, the combustible gas detection device also includes a storage circuit. The storage module receives the electrical signal output by the laser receiving system or the control circuit, and the storage module is used to store the measured concentration obtained within a preset period.

[0009] The control circuit selects the measured concentration within a preset range of concentration change in a preset period as the calibration concentration; the control circuit calculates the weight of the duration of the calibration concentration in the preset period, and updates the calibration concentration with the weight satisfying the set weight as the reference concentration.

[0010] Furthermore, the propagation path of the laser beam is defined as the set optical path, and the ratio between the thickness of the gas container along the extension direction of the set optical path and the length of the set optical path is greater than 0 and less than 0.8.

[0011] Furthermore, the gas container has an injection surface and an exit surface that intersect the injection direction of the laser beam, the injection surface and the exit surface are parallel, and the angle between the injection direction of the laser beam and the injection surface is greater than or equal to 30° and less than or equal to 90°.

[0012] Furthermore, the combustible gas detection device includes a base plate, a laser emitting system, a laser receiving system, and a gas container integrated on the base plate, which is detachably mounted on a circuit board.

[0013] Furthermore, the base plate has multiple mounting positions located between the laser emitting system and the laser receiving system, and the gas container is fixed in any of these mounting positions.

[0014] Furthermore, the combustible gas detection device also includes a reflector mounted on the base plate, through which the laser beam changes its propagation path, and a gas container is positioned between the reflector and the laser emitting system, or between the reflector and the laser receiving system.

[0015] Furthermore, the combustible gas detection device also includes a support structure, through which the gas container is movably mounted on the base plate and has a degree of freedom of movement perpendicular to the direction of laser beam incidence.

[0016] Furthermore, the support structure extends substantially along a predetermined straight line, the gas container is rotatably mounted on the support structure, and has circumferential freedom of movement along the predetermined straight line, which extends substantially along the height direction of the combustible gas detection device.

[0017] Furthermore, the laser emitting system is fixedly mounted in a gas container and encapsulated within a cavity; or the laser receiving system is fixedly mounted in a gas container and encapsulated within a cavity.

[0018] This invention provides a combustible gas detection device. Compared to existing technologies, it places a gas container filled with a target gas of known concentration along the propagation path of a laser beam. Using the concentration of the target gas in the cavity as a reference concentration, the device acquires a measured concentration of the target gas when the laser beam passes through at least partially through the gas container. The difference between the measured concentration and the reference concentration is calculated by a control circuit to obtain the actual concentration of the target gas in the environment. This solves the problem of low measurement accuracy in existing combustible gas detection devices. Furthermore, the overall structure of the combustible gas detection device in this invention is smaller, making it suitable for use in home environments. Attached Figure Description

[0019] Figure 1 This is a structural diagram of the combustible gas detection device in the embodiments of this application.

[0020] Figure 2 This is a diagram showing the internal circuit structure of the combustible gas detection device in the embodiments of this application.

[0021] Figure 3 This is a schematic diagram of the gas container from a first-view perspective in an embodiment of this application.

[0022] Figure 4 This is a schematic diagram showing the connection of the control circuit and its peripheral circuits in the embodiments of this application.

[0023] Figure 5 This is a schematic diagram of the gas container from a second perspective in an embodiment of this application.

[0024] Figure 6 This is a schematic diagram of the installation of the reflector in an embodiment of this application.

[0025] Figure 7 This is a flowchart of the combustible gas detection method in the embodiments of this application. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present application, the technical solutions in specific embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0027] like Figure 1 As shown, this application provides a combustible gas detection device 100 for detecting target gas leaks in the external environment. The target gas can be an alkane gas such as methane or ethane, or it can be a trace amount of inert gas contained within the combustible gas.

[0028] like Figures 1 to 3 As shown, in one implementation, the combustible gas detection device 100 includes a housing 11 and a circuit board 12 disposed inside the housing 11. The housing 11 forms the basic framework of the combustible gas detection device 100. At least one vent 111 is provided on the housing 11, and the interior of the housing 11 communicates with the external environment through the vent 111. This allows the combustible gas detection device 100 to respond promptly when a target gas leak occurs in the external environment.

[0029] Specifically, the combustible gas detection device 100 includes a laser emitting system 13, a laser receiving system 14, and a control circuit 15. The laser emitting system 13 is at least partially mounted on the circuit board 12. The laser emitting system 13 is used to convert electrical energy into light energy. The laser emitting system 13 generally consists of a laser tube, a power supply, and a modulation circuit. When powered, photons in the laser tube are modulated by the modulation circuit and oscillate, forming a laser beam, which is then emitted outward along a predetermined optical path. In some examples, the power supply may be an external power source and not part of the laser emitting system 13 itself.

[0030] Furthermore, the laser receiving system 14 is at least partially disposed on the circuit board 12. The laser receiving system 14 is used to receive the laser beam transmitted along the set optical path and convert it into an electrical signal characterizing the measured concentration of the target gas in the set optical path. The laser receiving system 14 includes at least a demodulation circuit, which generates an electrical signal of corresponding intensity based on the spectral intensity signal of the received laser beam, thereby obtaining the measured concentration of the target gas.

[0031] In this embodiment of the application, the control circuit 15 is at least partially disposed on the circuit board 12 and is electrically connected to the laser receiving system 14 through the metal wire of the circuit board 12. The control circuit 15 is used to acquire the electrical signal generated by the laser receiving system 14 and determine the measurement concentration of the target gas in the set optical path according to the electrical signal.

[0032] Understandably, the optical path is set as the propagation path of the laser beam from the laser emitting system 13 to the laser receiving system 14.

[0033] like Figure 3 As shown, in one implementation, the combustible gas detection device 100 also includes a gas container 16, at least partially disposed in the set optical path. The gas container 16 is made of a colorless and transparent material through which the laser beam can pass. The gas container 16 has a closed cavity filled with a target gas of known concentration. By replacing the gas container 16 filled with the corresponding target gas, different target gas concentrations can be detected. The gas container 16 is detachably mounted on the circuit board 12, allowing the detection of different target gases by replacing the gas container 16 filled with different target gases.

[0034] For example, the combustible gas detection device 100 provided in this application embodiment is applied to the detection of target gas concentration in a home environment. Due to limitations of the usage environment, homes often lack sufficient space to accommodate the combustible gas detection device 100. Therefore, the gas container 16 is small in size, and the sealing performance of the gas container is crucial to maintain a constant concentration of the target gas within the gas container 16, preventing leakage that could affect the detection accuracy of the device. Optionally, different types of target gases can be detected by replacing the gas container 16 with one filled with a different type of target gas. Compared to industrial applications, this device offers advantages such as convenient installation, small size, and high detection accuracy.

[0035] The gas container 16 can be made of glass, plastic, or other materials.

[0036] Specifically, the control circuit 15 receives the electrical signal sent by the laser receiving system 14 and determines the concentration of the target gas interacting with the laser beam based on the electrical signal (the center wavelength of the laser beam is the absorption spectral line of the target gas, causing selective absorption by the target gas, and the concentration of the target gas is inverted using the spectral intensity signal obtained after absorption by the target gas). This is used as the measured concentration, which is the sum of the concentrations of the target gas inside and outside the gas container 16. The control circuit 15 uses the concentration of the target gas in the cavity as the reference concentration and determines the actual concentration of the target gas outside the gas container 16, i.e., the concentration of the target gas leaking from the external environment, based on the difference between the measured concentration and the reference concentration.

[0037] It should be noted that when detecting the concentration of a target gas using laser, the longer the optical path, the higher the detection accuracy of the actual concentration of the target gas. Through the above settings, the miniaturization of the combustible gas detection device is achieved while maintaining its detection accuracy.

[0038] For example, a household combustible gas laser sensor cannot detect methane gas leaks at concentrations of 3% LEL or lower in the air, meaning it outputs a measured concentration of 0% LEL. In this embodiment, by filling the gas container 16 with methane gas at a concentration of 20% LEL, the methane gas concentration measured by the control circuit 15 in an environment without methane gas leaks is 4% LEL, and this 4% LEL is used as the baseline concentration when there is no methane gas leak. Taking a methane gas leak concentration of 1% LEL in the external environment as an example, the measured concentration of methane gas obtained by the control circuit 15 is 5.2% LEL. The control circuit 15 multiplies the difference between the measured concentration of 5.2% LEL and the baseline concentration by a correction factor of 0.833, which is related to the magnitude of the difference, to determine that the methane gas leak concentration in the external environment is 1% LEL (the result is rounded).

[0039] In some examples, the above settings enable the combustible gas detection device 100 to detect leaks of target gases with a concentration of less than 1% LEL. Compared with existing detection methods, the combustible gas detection device 100 provided in this application has higher detection accuracy and greatly reduces safety hazards.

[0040] like Figure 4 As shown, in one implementation, the combustible gas detection device 100 also includes a storage circuit 17. The storage circuit 17 is mounted on the circuit board 12 and electrically connected to the control circuit 15 or the laser receiving system 14 via metal wires on the circuit board 12. The storage circuit 17 is used to receive electrical signals characterizing the measured concentration of the target gas sent by the control circuit 15 or the laser receiving system 14, and to store the measured concentrations acquired within a preset period. The preset period can be one week or one month, so that the combustible gas detection device 100 can calibrate the reference concentration based on the measured concentrations acquired within the preset period.

[0041] It should be noted that, since the combustible gas detector 100 is generally installed near the gas pipeline, especially in a home environment, the combustible gas detector 100 is easily affected by dust and oil, which can cause factors that hinder the normal propagation of the laser beam in the optical path, thereby affecting the detection effect of the actual concentration of the target gas.

[0042] For example, dust particles covering the gas container 16 can cause scattering of the laser beam, thereby affecting the laser receiving system 14 in acquiring the measured concentration of the target gas.

[0043] In this embodiment, the control circuit 15 selects a measurement concentration whose concentration change falls within a preset range within a preset period, and uses the selected measurement concentration as the calibration concentration. The control circuit 15 calculates the weight of the duration of the calibration concentration within the preset period, and updates the calibration concentration with a weight that satisfies the set weight as the reference concentration.

[0044] It should be noted that when the target gas does not leak, the combustible gas detection device 100 is in a steady state, meaning the measured concentration remains essentially constant, and this measured concentration serves as the reference concentration. If a factor obstructs the normal propagation of the laser beam in the optical path, even if the target gas does not leak, the measured concentration will deviate from the predetermined reference concentration, leading to a discrepancy between the actual concentration determined based on the reference concentration and the measured concentration.

[0045] Through the above settings, the predetermined reference concentration is calibrated every preset period to ensure the measurement accuracy of the combustible gas detector 100 for the target gas.

[0046] like Figure 5 As shown, the laser emitting system 13, the gas container 16, and the laser emitting system 13 are arranged sequentially along the reference line 132, and the extension direction of the set optical path is substantially parallel to the direction of the reference line 132. In one implementation, the ratio between the thickness L1 of the gas container 16 extending along the reference line 132 and the length L2 of the set optical path is greater than 0 and less than or equal to 0.8. Further, the ratio between the thickness L1 of the gas container 16 extending along the reference line 132 and the length L2 of the set optical path is greater than 0 and less than or equal to 0.7. The ratio between the thickness L1 of the gas container 16 extending along the reference line 132 and the length L2 of the set optical path is greater than 0 and less than or equal to 0.65. It should be noted that, in addition to allowing the laser beam to pass through the gas container 16, the laser beam also needs to pass through the space outside the gas container 16 so that the target gas outside the gas container 16 can fully absorb the laser beam of a specific wavelength. Therefore, if the ratio between the thickness L1 of the gas container 16 extending along the reference straight line 132 and the length L2 of the set optical path is too large, the measurement accuracy will be insufficient. Through the above settings, while ensuring the accuracy of detecting the actual concentration of the target gas, the combustible gas detector 100 is also designed for miniaturized applications in household settings.

[0047] Optionally, the gas container 16 has an injection surface and an exit surface that intersect the injection direction of the laser beam, with the injection surface and exit surface being parallel. The angle α between the injection direction of the laser beam and the injection surface is greater than or equal to 30° and less than 90°. Further, the angle α between the injection direction of the laser beam and the injection surface is greater than or equal to 35° and less than or equal to 80°. More preferably, the angle α between the injection direction of the laser beam and the injection surface is greater than or equal to 40° and less than or equal to 70°. It should be noted that when the injection direction of the laser beam intersects the injection surface at a 90° angle, some light rays in the laser beam may be reflected or refracted. The above arrangement can avoid the scattering generated by the laser beam passing through the surface of the gas container 16 from affecting the laser receiving system 14, thereby ensuring the detection accuracy of the combustible gas detection device 100 for the target gas.

[0048] like Figure 5 As shown, in one implementation, the combustible gas detection device 100 also includes a base plate 18, on which the laser emitting system 13, the laser receiving system 14, and the gas container 16 are integrated, so that the above components form a whole, so that the laser emitting system 13, the laser receiving system 14, and the gas container 16 will not undergo large deformations that would affect the measurement accuracy, and also facilitate the maintenance and replacement of any component of the laser emitting system 13, the laser receiving system 14, and the gas container 16.

[0049] like Figure 6 As shown, in some examples, the combustible gas detection device 100 also includes a reflector disposed on the base plate 18, which doubles the length of the propagation path of the laser beam. Since the detection accuracy of the combustible gas detection device 100 is positively correlated with the length of the propagation path of the laser beam, the detection accuracy of the combustible gas detection device 100 is improved by setting at least one reflector.

[0050] Specifically, the gas container 16 is disposed between the reflector and the laser emitting system 13; or the gas container 16 is disposed between the reflector and the laser receiving system 14.

[0051] The base plate 18 has multiple mounting positions located between the laser emitting system 13 and the laser receiving system 14, and the gas container 16 is fixed at any of these mounting positions. By adjusting the mounting position of the gas container 16, the laser beam can fully interact with the target gas in the environment.

[0052] like Figure 5 As shown, in one implementation, the combustible gas detection device 100 also includes a support structure 19, and the gas container 16 is mounted on the base plate 18 through the support structure 19 so that the gas container 16 has a degree of freedom of movement perpendicular to the direction of laser beam incidence.

[0053] Specifically, one end of the support structure 19 is fixedly connected to the gas container 16, and the other end of the support structure 19 is movably mounted on the base plate 18. A slide rail is provided on the base plate 18 to cooperate with the support structure 19, and the support structure 19 can move relative to the base plate 18 in the extension direction of the slide rail.

[0054] Furthermore, the support structure 19 extends substantially along the direction of the preset straight line 191 and is telescopic in the direction of the preset straight line 191, thereby adjusting the relative distance between the gas container 16 and the base plate 18.

[0055] The above settings facilitate the calibration of the detection accuracy of the combustible gas detection device 100, thereby avoiding the influence of scattering and refraction of the laser beam as it passes through the gas container 16 on the detection results.

[0056] Optionally, the support structure 19 extends substantially along the direction of a preset straight line 191, and the gas container 16 is rotatably mounted on the support structure 19 so that the gas container 16 has rotational freedom along the circumferential direction of the preset straight line 191, wherein the preset straight line 191 extends substantially along the height direction of the combustible gas detection device 100.

[0057] For example, the end of the support structure 19 facing away from the gas container 16 is connected to a motor, which drives the support structure 19 to move or rotate, thereby moving the gas container 16. Alternatively, the support structure 19 or the gas container 16 can be moved manually.

[0058] The above settings facilitate the calibration of the detection accuracy of the combustible gas detection device 100, thereby avoiding the influence of scattering and refraction of the laser beam as it passes through the gas container 16 on the detection results.

[0059] As one implementation, in order to reduce the number of components in the combustible gas detection device 100, the laser emitting system 13 or the laser receiving system 14 is integrated into the gas container 16, so that the laser emitting system 13 or the laser receiving system 14 and the gas container 16 form a whole, so as to facilitate the installation of components in the combustible gas detection device 100.

[0060] Specifically, the laser emitting system 13 is fixedly mounted on the gas container 16 and encapsulated within the cavity formed by the gas container 16. Alternatively, the laser receiving system 14 is fixedly mounted on the gas container 16 and encapsulated within the cavity formed by the gas container 16.

[0061] like Figure 7 As shown, this application also provides a method for detecting combustible gases, which specifically includes the following steps:

[0062] S101: The concentration of the target gas inside the cavity of the gas container is used as a reference concentration.

[0063] For example, the detection of different gas leaks in the external environment can be achieved by varying the type of target gas filled in the gas container 16. The cavity of the gas container 16 is filled with a target gas of known concentration, and the concentration of the target gas in the cavity is determined as a baseline concentration, which serves as a benchmark for detecting target gas leaks outside the gas container 16 when a target gas leak occurs.

[0064] S102: Receive a laser beam that passes at least partially through the gas container 16 to determine the measured concentration of the target gas, wherein the measured concentration is the sum of the concentrations of the target gas inside the gas container 16 and the target gas leaking externally.

[0065] For example, the laser emitting system 13 outputs a laser beam of a specific wavelength that can be absorbed by the target gas through a modulation circuit. This laser beam is partially absorbed by the target gas diffused in the optical path and reaches the laser receiving system 14. The laser receiving system 14 receives the laser beam and, based on the received laser spectral intensity signal and other information, calculates the concentration of the target gas. It should be noted that there are some limitations to detecting the concentration of the target gas using a laser beam. When a trace amount of target gas leaks in the external environment, the detection accuracy of the combustible gas detector 100 may prevent it from displaying a reading, or the combustible gas detector 100 may display a concentration of 0 for the target gas in the external environment.

[0066] Furthermore, if the detection accuracy of the combustible gas detector 100 is improved by increasing the length of the laser beam's propagation path, the overall size of the combustible gas detector 100 will be too large or the cost too high, making it difficult to achieve miniaturization and low-cost application in a home environment.

[0067] In this embodiment of the application, a gas container 16 filled with a target gas of known concentration is set in the propagation path of the laser beam, so that when the laser beam passes through the gas container 16, the gas molecules will absorb the laser energy, resulting in a significant attenuation of the light intensity of the laser beam, so that the spectral intensity signal obtained by the laser receiving system 14 can reflect the concentration of the target gas outside the gas container 16.

[0068] S103: Determine the actual concentration of the target gas outside the gas container 16 based on the difference between the measured concentration and the reference concentration.

[0069] It should be noted that although the steps in the above process or the flowchart in the accompanying figure show a logical order, in some cases, the steps shown or described may be performed in a different order than that shown here.

[0070] As an implementation method, to avoid the influence of dust, oil, and other factors on the combustible gas detection device 100, the combustible gas detection method also includes the following steps:

[0071] S104: Store the measured concentrations acquired within a preset period.

[0072] S105: Select the concentration that changes within a preset range during the preset period as the calibration concentration.

[0073] S106: Calculate the weight of the duration of the calibration concentration in the preset period, and update the calibration concentration with the weight that meets the set weight as the reference concentration.

[0074] In this way, the combustible gas detection device 100 can achieve self-calibration of the reference concentration every preset period, thereby ensuring its accuracy in detecting whether a target gas leak has occurred in the external environment and further reducing the safety risk of target gas leaks.

[0075] In summary, by filling the gas container 16 with a target gas of known concentration and using the concentration of the target gas within the gas container 16 as a reference concentration, the laser beam exhibits a relatively significant intensity attenuation even in the event of a minor leak of the target gas. This allows the laser receiving system 14 to generate a corresponding electrical signal characterizing the measured concentration of the target gas. Furthermore, the actual concentration of the target gas in the external environment is determined by measuring the difference between the measured concentration and the reference concentration. The aforementioned method requires relatively low improvement costs and offers high detection accuracy.

[0076] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A combustible gas detection device, comprising a housing and a circuit board, wherein the housing has at least one vent hole, the interior of the housing communicates with the external environment through the vent hole, and the circuit board is fixedly disposed inside the housing, characterized in that... include: A laser emitting system, wherein the laser emitting system is used to emit a laser beam; A gas container through which the laser beam can pass, the gas container being at least partially disposed in the propagation path of the laser beam, the gas container having a closed cavity filled with a target gas of known concentration, wherein the gas container is detachably mounted on the circuit board, and different target gases can be detected by replacing the gas container filled with different target gases; A laser receiving system, wherein the laser receiving system is used to receive the laser beam passing through the gas container and generate an electrical signal based on the received laser beam; A control circuit, electrically connected to the laser receiving system, determines the concentration of the target gas interacting with the laser beam based on the electrical signal, as a measured concentration; the control circuit stores the concentration of the target gas in the cavity as a reference concentration, and the control circuit determines the actual concentration of the target gas in the environment based on the difference between the measured concentration and the reference concentration.

2. The combustible gas detection device according to claim 1, characterized in that, The combustible gas detection device further includes a storage circuit, which receives the electrical signal output by the laser receiving system or the control circuit, and is used to store the measured concentration obtained within a preset period. The control circuit selects the measured concentration whose concentration change is within a preset range during the preset period as the calibration concentration; the control circuit calculates the weight of the duration of the calibration concentration in the preset period, and updates the calibration concentration whose weight satisfies the set weight as the reference concentration.

3. The combustible gas detection device according to claim 1, characterized in that, The propagation path of the laser beam is defined as a set optical path, and the ratio between the thickness of the gas container along the extension direction of the set optical path and the length of the set optical path is greater than 0 and less than 0.

8.

4. The combustible gas detection device according to claim 1, characterized in that, The gas container has an injection surface and an exit surface that intersect the injection direction of the laser beam, the injection surface and the exit surface are parallel, and the angle between the injection direction of the laser beam and the injection surface is greater than or equal to 30° and less than or equal to 90°.

5. The combustible gas detection device according to claim 1, characterized in that, The combustible gas detection device includes a base plate, on which the laser emitting system, the laser receiving system and the gas container are integrated. The base plate is detachably mounted on the circuit board.

6. The combustible gas detection device according to claim 5, characterized in that, The base plate has multiple mounting positions, which are located between the laser emitting system and the laser receiving system, and the gas container is fixed at any one of the multiple mounting positions.

7. The combustible gas detection device according to claim 5, characterized in that, The combustible gas detection device also includes a reflector disposed on the base plate, the laser beam changes its propagation path through the reflector, and the gas container is disposed between the reflector and the laser emitting system, or the gas container is disposed between the reflector and the laser receiving system.

8. The combustible gas detection device according to claim 5, characterized in that, The combustible gas detection device also includes a support structure, through which the gas container is movably mounted on the base plate and has a degree of freedom of movement perpendicular to the direction of incidence of the laser beam.

9. The combustible gas detection device according to claim 8, characterized in that, The support structure extends substantially along a predetermined straight line, the gas container is rotatably mounted on the support structure and has circumferential freedom of movement along the predetermined straight line, which extends substantially along the height direction of the combustible gas detection device.

10. The combustible gas detection device according to claim 1, characterized in that, The laser emitting system is fixedly installed in the gas container and encapsulated within the cavity; or the laser receiving system is fixedly installed in the gas container and encapsulated within the cavity.

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