Efficient folding type gas detection device

Abstract

The utility model relates to the technical field of gas absorption cells, in particular to an efficient folding type gas detection device which comprises a shell. A laser entrance port, a laser exit port, an air inlet and an air outlet are formed in the shell, and a plurality of reflecting lenses are arranged in the shell and comprise a first lens, a second lens, a third lens, a fourth lens and a fifth lens; the first lens and the third lens are arranged on the same side of the shell, and the second lens, the fourth lens and the fifth lens are arranged on the other side of the shell; a laser beam enters the shell through the laser entrance port, is reflected by the reflecting lens in the shell, and then is emitted through the laser exit port, so that the concentration of harmful substances (single or multiple gases) in to-be-detected gas is detected. According to the utility model, through the spatial arrangement of the plurality of reflecting lenses, the volume of the cavity is reduced, so that the responsivity and the accuracy in the detection process are improved, the missing report can be effectively avoided, and the positive and beneficial effects are achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of gas absorption cells, in particular to a high-efficiency foldable gas detection device. Background Art

[0002] Gas absorption cells are based on the application and development of optical gas absorption cells in the field of tunable semiconductor laser absorption spectroscopy (TDLAS) technology. According to the development needs of TDLAS technology, gas absorption cells currently have the development trend of long optical path, miniaturization, easy operation, high stability and simultaneous measurement of multiple gases. They are widely used in air pollution research, environmental monitoring, gas purity analysis, industrial production process monitoring, emission gas analysis and oil exploration geological logging process monitoring. In addition, in view of the serious harm caused by gas leakage, especially fuel gas leakage, to personnel and property, gas absorption cells can also be used for gas leakage detection, which plays a positive role in ensuring the safety of people's lives and property.

[0003] When the gas absorption cell is in use, the gas to be measured enters the gas cell through the air inlet and is discharged from the air outlet; the laser beam is collimated and enters the absorption cell to react with the specific gas. The light signal carrying the gas concentration is emitted from the light outlet and converted into a weak electrical signal by the photoelectric receiver. The concentration of the gas to be measured is obtained through analytical calculation.

[0004] The accuracy of existing gas absorption cells is relatively poor. They are generally based on two or more concave mirrors placed relative to each other at a specific distance. The laser beam is incident at a specific angle and is reflected back and forth between the mirrors multiple times before being emitted. However, to achieve a certain detection capability, a sufficient optical path is required, and a sufficiently large mirror and cavity volume are required. This requires a large amount of detection gas sample, which affects the system response time and will cause missed detection during mobile detection. Therefore, we propose a gas absorption cell that can achieve high efficiency and accuracy during the detection process to solve the problems existing in the existing technology. Utility Model Content

[0005] The purpose of the present invention is to provide a high-efficiency foldable gas detection device to address the deficiencies of the above-mentioned prior art, so as to achieve the purpose of efficient and accurate detection during the detection process.

[0006] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: a high-efficiency foldable gas detection device, comprising a shell, on which a laser incident port, a laser exit port, an air inlet and an air outlet are provided, and five lenses are arranged in the shell, namely a first lens, a second lens, a third lens, a fourth lens and a fifth lens; the first lens and the third lens are arranged on the same side of the shell, and the second lens, the fourth lens and the fifth lens are arranged on the other side of the shell.

[0007] Furthermore, transparent sealing sheets are provided at the laser incident port and the laser exit port.

[0008] Furthermore, the first lens and the third lens are arranged on a side of the shell having the laser incident port and the laser exit port.

[0009] Furthermore, the air inlet is arranged at the bottom of one side of the shell, and the air outlet is arranged at the upper part of one side of the shell.

[0010] Furthermore, the third lens is installed below the first lens, and the fourth lens and the fifth lens are installed below the second lens.

[0011] Furthermore, the first lens, the fourth lens, and the fifth lens are concave reflectors with the same curvature; the second lens and the third lens are plane mirrors and the reflective surfaces have the same inclination angle.

[0012] Furthermore, the fourth lens and the fifth lens are arranged in parallel.

[0013] Furthermore, the reflective surfaces of the first lens, the second lens, the third lens, the fourth lens, and the fifth lens are all coated with a high-reflection film.

[0014] Furthermore, the fourth lens and the fifth lens are respectively connected to the optical fine-tuning mechanism.

[0015] Furthermore, a temperature and pressure sensing module is provided at the bottom of the shell, the temperature and pressure sensing module is connected to the single chip microcomputer, and the single chip microcomputer is connected to the thermoelectric cooler.

[0016] Beneficial effects of the utility model:

[0017] 1. Compared with traditional absorption cells, this utility model has higher lens utilization, improved optical path to volume ratio, shortened cavity length by more than 65%, and reduced cavity volume by more than 50%, effectively improving system responsiveness and avoiding the harm caused by missed detection and missed reporting, and missing the best time to deal with gas leaks;

[0018] 2. The utility model can also ensure the stability of the detection environment during use, and improve the detection precision, accuracy and reliability;

[0019] 3. Adding a two-dimensional adjustment frame to the fourth lens and the fifth lens can quickly adjust the optical path number and effective optical path according to the different requirements of the use environment and detection accuracy, making it more convenient to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the internal structure of the shell of the utility model;

[0021] Figure 2This utility model Figure 1 Schematic diagram of the right side of the AA surface;

[0022] Figure 3 This utility model Figure 1 Left view of the middle AA surface;

[0023] Figure 4 This utility model Figure 1 Schematic diagram of the rear view of the middle BB surface.

[0024] The names corresponding to the marks in the figure are:

[0025] 1. Shell; 11. Laser incident port; 12. Laser exit port; 13. Air inlet; 14. Air outlet; 2. Transparent sealing sheet; 3. First lens; 4. Second lens; 5. Third lens; 6. Fourth lens; 7. Fifth lens; 8. Thermoelectric cooler; 9. Temperature and pressure sensor module. DETAILED DESCRIPTION

[0026] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field fall within the scope of protection of the present invention.

[0027] Embodiments of the present utility model:

[0028] like Figure 1-3 As shown, in this embodiment, a shell 1 is provided, a cover is detachably and sealedly connected to the top of the shell 1, a laser inlet 11 and a laser outlet 12 are provided on the left side of the shell 1, and an air inlet 13 and an air outlet 14 are provided on the front side of the shell 1.

[0029] In one embodiment of the present invention, a transparent sealing sheet 2 is provided at the laser incident port 11 and the laser exit port 12 .

[0030] In another embodiment of the present invention, the air inlet 13 is located at the lower front side of the housing 1 , and the air outlet 14 is located at the upper front side of the housing 1 .

[0031] A first lens 3, a second lens 4, a third lens 5, a fourth lens 6 and a fifth lens 7 are arranged and installed in the housing 1, wherein the first lens 3 and the third lens 5 are installed on the same side of the housing 1, and the second lens 4, the fourth lens 6 and the fifth lens 7 are installed on the other side of the housing 1.

[0032] In one embodiment of the present invention, the second lens 4 and the third lens 5 are installed on the housing 1 at a side having the laser incident port 11 and the laser exit port 12 .

[0033] In another embodiment of the present invention, the third lens 5 is installed below the first lens 3 , and the fourth lens 6 and the fifth lens 7 are installed below the second lens 4 .

[0034] In another embodiment of the present invention, the fourth lens 6 and the fifth lens 7 are arranged in parallel.

[0035] In another embodiment of the present invention, the first lens 3, the fourth lens 6, and the fifth lens 7 are concave reflectors with the same curvature; the second lens 4 and the third lens 5 are plane mirrors and their reflective surfaces have the same inclination angle.

[0036] In another embodiment of the present invention, the reflective surfaces of the first lens 3, the second lens 4, the third lens 5, the fourth lens 6, and the fifth lens 7 are all coated with a high-reflection film (the high-reflection film is a mature material and process, which will not be described in detail).

[0037] In another embodiment of the present invention, the fourth lens 6 and the fifth lens 7 are respectively connected to an optical fine-tuning mechanism (two-dimensional adjustment frame).

[0038] A temperature and pressure sensing module 9 is provided at the bottom of the housing 1 . The temperature and pressure sensing module 9 is connected to a single chip microcomputer, and the single chip microcomputer is connected to a thermoelectric cooler 8 .

[0039] The principle of this utility model is:

[0040] The gas to be detected is introduced into the housing 1 through the air inlet 13 , and the transparent sealing sheet 2 at the laser incident port 11 and the laser exit port 12 plays a sealing role.

[0041] At this time, the laser beam is injected into the housing 1 from the laser incident port 11, and the laser beam is irradiated on the second lens 4 after passing through the first lens 3, and then reflected by the second lens 4 to the third lens 5, and then irradiated on the first lens 3 through the third lens 5 and the second lens 4; then it is passed from the first lens 3 through the second and third reflectors to the fourth lens 6, and reflected to the first lens 3 through the fourth lens 6, and then passed through the first lens 3, the second lens 4, the third lens 5 to the fifth lens 7, and so on and so forth through the first lens 3, the second lens 4, the third lens 5, the fourth lens 6, and the fifth lens 7, and folded many times, and finally emitted through the laser exit port 12, and then irradiated on the photoelectric sensor. Due to the change in the spectrum, it is converted into an electrical signal with gas concentration by the photoelectric sensor, thereby realizing the detection of the gas concentration in the gas to be measured.

[0042] Compared with the traditional absorption cell, the utility model has a higher lens utilization rate, improves the optical path to volume ratio, shortens the cavity length by more than 65%, and reduces the cavity volume by more than 50%, effectively improving the system responsiveness, shortening the system response time, and avoiding the hazards caused by missed detection and missed reporting, and missing the best time to deal with gas leaks; a two-dimensional adjustment frame is set at the fourth lens 6 and the fifth lens 7, and the optical path number and the effective optical path can be quickly adjusted according to the different requirements of the use environment and detection accuracy, which is more convenient to use. The two-dimensional adjustment frame is commonly used in the installation of existing optical lenses, and the specific structure will not be repeated here.

[0043] The utility model can also ensure the stability of the detection environment (temperature and pressure) during use, and improve the detection precision, accuracy and reliability.

Claims

1. A high-efficiency foldable gas detection device, comprising a housing (1), wherein the housing (1) is provided with a laser incident port (11), a laser exit port (12), an air inlet (13) and an air outlet (14), and wherein: Five lenses are arranged in the housing (1), namely a first lens (3), a second lens (4), a third lens (5), a fourth lens (6) and a fifth lens (7); the first lens (3) and the third lens (5) are arranged on the same side of the housing (1), and the second lens (4), the fourth lens (6) and the fifth lens (7) are arranged on the other side of the housing (1).

2. A high-efficiency foldable gas detection device according to claim 1, characterized in that: Transparent sealing sheets (2) are provided at the laser incident port (11) and the laser exit port (12).

3. The high-efficiency foldable gas detection device according to claim 1, characterized in that: The first lens (3) and the third lens (5) are arranged on a side of the housing (1) having a laser incident port (11) and a laser exit port (12).

4. The high-efficiency foldable gas detection device according to claim 1, characterized in that: The air inlet (13) is arranged at the bottom of one side of the shell (1), and the air outlet (14) is arranged at the upper part of one side of the shell (1).

5. The high-efficiency foldable gas detection device according to claim 1, characterized in that: The third lens (5) is installed below the first lens (3), and the fourth lens (6) and the fifth lens (7) are installed below the second lens (4).

6. The high-efficiency foldable gas detection device according to claim 5, characterized in that: The first lens (3), the fourth lens (6), and the fifth lens (7) are concave reflectors with the same curvature; the second lens (4) and the third lens (5) are plane mirrors with the same inclination angle on their reflective surfaces.

7. The high-efficiency foldable gas detection device according to claim 5, characterized in that: The fourth lens (6) and the fifth lens (7) are arranged in parallel.

8. The high-efficiency foldable gas detection device according to claim 1, characterized in that: The reflective surfaces of the first lens (3), the second lens (4), the third lens (5), the fourth lens (6), and the fifth lens (7) are all coated with a high-reflection film.

9. The high-efficiency foldable gas detection device according to claim 1, characterized in that: The fourth lens (6) and the fifth lens (7) are respectively connected to the optical fine-tuning mechanism.

10. The high-efficiency foldable gas detection device according to claim 1, characterized in that: A temperature and pressure sensing module (9) is provided at the bottom of the housing (1); the temperature and pressure sensing module (9) is connected to a single-chip microcomputer, and the single-chip microcomputer is connected to a thermoelectric cooler (8).

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