A constant temperature gas chamber for NH3 gas detection

Abstract

The utility model relates to environmental engineering technical field, concretely for a kind of thermostatic chamber for NH3 gas detection, including gas chamber main body, the both ends of gas chamber main body are respectively equipped with laser emission module and laser reflection module, and the lens support is equipped in the both ends of gas chamber main body, the inboard of lens support is equipped with lens, and the pipe opening of gas chamber main body is equipped with sealing assembly and heat insulation component, and the outside of gas chamber main body is wrapped and is equipped with heating mechanism. The thermostatic chamber for NH3 gas detection, by heating mechanism split type design, dismounting is convenient, is favorable to maintenance, and the gap is filled in top groove and filling groove with heat-conducting silicone grease, improves heat conduction efficiency, guarantees gas chamber circumferential temperature uniformity, mica heating sheet high-temperature insulation, heating stable, long service life;Cover plate fixed protection heating sheet, reduce heat loss, cooperate temperature sensor to realize 180±0.5 ℃ thermostatic control, reduce temperature change and water vapor to the interference of measurement, enhance equipment environmental adaptability.

Description

Technical Field

[0001] This utility model relates to the field of environmental engineering technology, specifically to a constant temperature gas chamber for NH3 gas detection. Background Technology

[0002] In the field of ammonia detection, detection equipment using tunable laser absorption spectroscopy technology is widely used due to its advantages such as high accuracy and fast response. However, in practical applications, temperature fluctuations and water vapor interference have become key issues affecting detection accuracy.

[0003] Traditional ammonia detection chambers lack effective temperature control mechanisms. Changes in ambient temperature cause instability in the thermal motion of gas molecules within the chamber, leading to fluctuations in the laser absorption signal and ultimately resulting in inaccurate ammonia concentration detection results. Furthermore, the presence of moisture inside the chamber can interfere with the laser absorption characteristics, further reducing detection accuracy. In addition, some detection devices have poorly designed heating structures, insufficient contact between the heating element and the chamber, and uneven heat transfer, resulting in significant localized temperature differences within the chamber and hindering precise temperature control. Moreover, existing equipment often has a complex structure, making maintenance and disassembly difficult, causing numerous inconveniences for subsequent maintenance and troubleshooting. Utility Model Content

[0004] To achieve the above objectives, this utility model provides the following technical solution: a constant temperature gas chamber for NH3 gas detection, comprising a gas chamber body, with a laser emitting module and a laser reflecting module respectively installed at both ends of the gas chamber body, lens brackets provided at both openings of the gas chamber body, lenses installed on the inner side of the lens brackets, sealing components and heat insulation components provided at the openings of the gas chamber body, and a heating mechanism wrapped around the outside of the gas chamber body; the heating mechanism includes two sets of heating blocks wrapped around the outside of the gas chamber body by screws, the two sets of heating blocks being an upper block and a lower block, and the opposite side of the upper and lower blocks forming an arc shape adapted to the gas chamber body, a top groove being opened on the opposite side of the lower and upper blocks, and a cover plate covering the top groove being fixed by screws, and multiple filling grooves arranged at equal distances along the length of the top groove being opened inside, the top groove and the filling groove being filled with thermally conductive silicone grease, and a mica heating plate covering the filling groove being installed in the top groove, the mica heating plate being in contact with the thermally conductive silicone grease.

[0005] Furthermore, a side groove is provided at the opposite edges of the upper and lower blocks, and a temperature sensor is installed in the side groove.

[0006] Furthermore, each of the upper and lower blocks has a wire opening at its opposite edges, which is connected to the top groove and the side groove respectively, for the wires of the mica heating element and the temperature sensor to pass through.

[0007] Furthermore, the heat insulation assembly includes heat insulation pads for the air chamber tubes installed at the two openings of the air chamber body. The lens bracket is located inside the heat insulation pads for the air chamber tubes. A lens heat insulation ring is installed on one side of the lens bracket. A concave surface is formed on one side of the heat insulation pads for the air chamber tubes. The laser emitting module and the laser reflecting module are both installed in the corresponding concave surfaces. Heat insulation plates close to the side of the air chamber body are installed inside the laser emitting module and the laser reflecting module.

[0008] Furthermore, the sealing assembly includes a sealing ring embedded in two ports of the air chamber body. The sealing ring is in contact with the corresponding lens bracket. The inner side of the lens bracket has an annular edge with an annular groove. An elastic filler is provided in the annular groove. The lens is in contact with the annular edge and covers the annular groove.

[0009] Furthermore, the lens bracket is fixed to the air chamber body by screws, and a groove adapted to the screws is formed on the outer side of the lens heat insulation ring. The lens heat insulation ring and the lens bracket are fixed by screws.

[0010] Furthermore, the upper side of the heating block is provided with U-shaped grooves that are adapted to the smoke inlet and outlet of the gas chamber body.

[0011] Furthermore, two sets of half-grooves are provided on both sides of the lower block, and positioning holes are provided in the half-grooves. Upper grooves are provided on both sides of the upper block, which are opposite to the corresponding half-grooves.

[0012] Furthermore, a filter assembly and an ejector assembly are installed on the outer side of the lower block of the heating block.

[0013] Compared with the prior art, the technical solution of this application has the following beneficial effects:

[0014] This constant temperature chamber for NH3 gas detection features a split-type heating mechanism design, making it easy to disassemble and maintain. Thermally conductive silicone grease fills the gaps in the top and filling slots, improving heat transfer efficiency and ensuring uniform temperature throughout the chamber. The mica heating element is high-temperature resistant and insulating, providing stable heating and a long lifespan. The cover plate secures and protects the heating element, reducing heat loss. Combined with a temperature sensor, it achieves constant temperature control of 180±0.5℃, minimizing interference from temperature changes and moisture on the measurement and enhancing the equipment's environmental adaptability. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model;

[0016] Figure 2 This is a three-dimensional structural diagram of the upper block of the heating block in this utility model without the cover plate.

[0017] Figure 3 This utility model Figure 2 A three-dimensional structural diagram with the mica heating element and temperature sensor removed.

[0018] Figure 4 This utility model Figure 1 A rear sectional view of the connection structure of the right-side protective cover.

[0019] Figure 5 This utility model Figure 1 Rear cross-sectional view of the left side protective shield connection structure

[0020] Figure 6 This utility model Figure 1 Flowchart of gas chamber sampling for the middle filter assembly and jet assembly.

[0021] In the diagram: 1. Gas chamber body; 2. Heating block; 201. Top groove; 202. Filling groove; 203. Mica heating plate; 204. Cover plate; 205. Wire inlet; 206. Side groove; 207. Temperature sensor; 4. Half groove; 5. Positioning hole; 6. Upper groove; 7. U-shaped groove; 8. Gas chamber tube heat insulation gasket; 9. Sealing ring; 10. Lens bracket; 12. Lens heat insulation ring; 13. Groove opening; 14. Ring edge; 15. Ring groove; 17. Lens; 18. Heat insulation plate; 20. Laser emitting module; 21. Laser reflecting module; 22. Filter assembly; 23. Ejector assembly. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] Please see Figure 1-6This embodiment describes a constant-temperature gas chamber for NH3 gas detection, comprising a chamber body 1. A laser emitting module 20 and a laser reflecting module 21 are respectively installed at both ends of the chamber body 1. Lens supports 10 are provided at both openings of the chamber body 1, with lenses 17 installed on the inner side of each lens support 10. Sealing and heat insulation components are provided at the openings of the chamber body 1, and a heating mechanism is wrapped around the outside of the chamber body 1. The lens supports precisely fix the lenses, and in conjunction with the sealing components, ensure a stable laser transmission path and isolation between the inside and outside of the chamber, reducing optical loss and contamination interference, and improving detection accuracy. The heating mechanism and heat insulation components on the outside of the chamber body work together to maintain a stable internal temperature field in environments with high and low temperatures and large temperature differences, enhancing environmental adaptability. The dual protection of the sealing and heat insulation components also ensures the airtightness of the chamber, preventing gas leakage or external infiltration, while protecting core components from corrosion and contamination. Combined with a modular structural design, this reduces the probability of failure and extends service life, making it widely adaptable to high-precision requirements in various fields such as gas detection, precision optical experiments, and outdoor monitoring.

[0024] like Figure 2-3 The heating mechanism includes two sets of heating blocks 2 that are screwed and wrapped around the outside of the air chamber body 1. The heating blocks 2 are divided into upper blocks and lower blocks, and the opposite side of the upper blocks and lower blocks is an arc shape adapted to the air chamber body 1. The opposite side of the upper blocks and lower blocks is provided with a top groove 201 and a plurality of filling grooves 202 that are equidistantly distributed along the length of the top groove 201. The top groove 201 and the filling grooves 202 are filled with thermally conductive silicone grease. A mica heating plate 203 is installed in the top groove 201 to cover the filling groove 202. The mica heating plate 203 is attached to the thermally conductive silicone grease. The top groove 201 is covered by screws of the cover plate 204.

[0025] The heating block is designed with an upper and lower section, and its split structure allows for quick wrapping or disassembly of the air chamber body 1, greatly improving the ease of assembly and disassembly and facilitating later maintenance. Thermally conductive silicone grease is used in the top groove 201 and the filling groove 202 to fill the gap between the heating block 2 and the mica heating sheet 203, improving heat conduction efficiency and ensuring uniform circumferential temperature of the air chamber body 1. At the same time, the thermally conductive silicone grease in the filling groove 202 increases the contact area of ​​the thermally conductive silicone grease. All the thermally conductive silicone grease is integrated, enhancing the bonding stability and ensuring service life. The mica heating sheet 203 is resistant to high temperature, has good insulation properties, and stable heating power, avoiding local overheating during the heating process. It also has a long service life. The cover plate fixes and protects the mica heating sheet 203, preventing displacement or damage to the heating sheet and reducing heat loss.

[0026] The upper and lower blocks each have a side groove 206 and two sets of wire openings 205 that are connected to the top groove on the opposite side edge. A temperature sensor 207 is installed in the side groove, and the wire openings 205 are used for the wires of the mica heating plate 203 and the temperature sensor 207 to pass through.

[0027] Temperature sensor 207 is close to heating block 2 and can collect temperature data in real time to realize closed-loop regulation of heating power, so as to keep the temperature constant at 180±0.5℃, reduce the interference of temperature and water vapor on the measurement signal, and solve the problem of temperature fluctuation. The wire port 205 facilitates the wiring of the mica heating plate 203 and temperature sensor 207, avoids wire tangling, and improves the cleanliness and safety of the equipment.

[0028] To improve the heat insulation effect, the heat insulation component includes a gas chamber tube heat insulation pad 8 and a lens heat insulation ring 12. The gas chamber tube heat insulation pad 8 is installed at the opening of the gas chamber body 1. The lens bracket 10 is fixed to the gas chamber body 1 by screws. The outer side of the lens heat insulation ring 12 has a groove 13 that matches the screws. The lens heat insulation ring 12 and the lens bracket 10 are fixed by screws. One side of the gas chamber tube heat insulation pad 8 has a concave surface. The laser emitting module 20 and the laser reflecting module 21 are both installed in the corresponding concave surface. The laser emitting module 20 and the laser reflecting module 21 are both equipped with a heat insulation plate 18 close to the side of the gas chamber body 1. The heat insulation pad 8 of the gas chamber tube blocks the heat exchange between the gas chamber body 1 and the laser emitting module 20 and the laser reflecting module 21, preventing the external ambient temperature from being conducted to the inside of the gas chamber through the laser emitting module 20 and the laser reflecting module 21, thus maintaining a constant temperature environment in the gas chamber. The heat insulation ring 12 of the lens reduces the heat transfer between the lens 17 and the lens support 10, preventing the lens 17 from deforming due to temperature changes and ensuring the laser transmittance. The heat insulation plate 18 further isolates the heat from the laser emitting and receiving ends, preventing the heat from affecting the constant temperature state of the gas chamber body 1 and improving the temperature control stability.

[0029] To improve sealing, the sealing assembly includes a sealing ring 9 embedded in the inlet of the gas chamber body 1. The sealing ring is in contact with the corresponding lens holder. An annular edge 14 is formed on the inner side of the lens holder 10, and an annular groove 15 is formed on the annular edge. An elastic filler is provided in the annular groove 15. The lens 17 fits against the annular edge 14 and covers the annular groove 15. The sealing ring 9 achieves a primary seal between the gas chamber body 1 and the lens holder 10, preventing the infiltration of external air and moisture. The annular groove 15 and the elastic filler, such as a silicone strip, undergo elastic deformation after the lens 17 is pressed, achieving a secondary seal. The double sealing structure can effectively prevent moisture from entering the gas chamber, avoiding interference from moisture on laser absorption and improving detection accuracy. At the same time, the elastic filler can buffer the pressure on the lens 17 and prevent the lens from breaking.

[0030] In addition, the upper block of heating block 2 has a U-shaped groove 7, and the lower block has two sets of half-grooves 4 on both sides. The half-grooves 4 have positioning holes 5, and the upper block has upper grooves 6 on both sides that are opposite to the corresponding half-grooves 4. The U-shaped groove 7 is adapted to the inlet and outlet of the gas chamber body 1, without affecting the normal flow of ammonia, while ensuring that the heating block 2 completely covers the gas chamber body 1 without compromising the heating seal. When the upper and lower blocks are installed, the half-grooves 4, upper grooves 6, and positioning holes 5 can be accurately positioned through the positioning holes 5. The screws pass through the positioning holes 5 and are tightened to make the upper and lower blocks fit tightly, avoiding gaps between the heating block 2 and the gas chamber body 1, and ensuring the heat conduction effect.

[0031] Among them, such as Figure 6 The lower outer side of the heating block 2 is equipped with a filter assembly 22 and an ejector assembly 23. Externally input compressed air generates negative pressure suction force through the pipe joints at both ends of the ejector, which is transmitted to the gas chamber assembly cavity, and then the sample gas is extracted through the filter.

[0032] The working principle of the above embodiments is as follows:

[0033] The high-transmittance anti-reflection optical lens 17 is fixed at both ends of the gas chamber body through a customized lens bracket 10, which greatly reduces laser reflection loss. The sealing ring 9 is embedded in the pipe opening and fits the end face of the lens bracket. The annular groove 15 of the inner ring edge 14 of the lens bracket is filled with elastic sealant and pressed by the lens, which effectively prevents leakage of the gas to be tested and interference from the outside air. In terms of heat insulation, the heat insulation ring 12 of the lens and the heat insulation gasket 8 of the gas chamber tube form a barrier to block the heat exchange between the inside and outside of the gas chamber and ensure the basic constant temperature environment.

[0034] The heating mechanism and temperature sensor 207 form a closed-loop temperature control system to achieve precise constant temperature control, which is divided into two stages:

[0035] Temperature control: After the system is started, the mica heating element 203 in the heating block 2 outside the air chamber is powered on and heats up. The heat is evenly conducted to the heating block through the high thermal conductivity silicone grease in the filling groove 202, and then transferred to the air chamber through close contact, so that the internal temperature rises steadily to the preset target value.

[0036] Constant temperature maintenance: Temperature sensor 207 collects air chamber temperature data in real time and feeds it back to the temperature control module; the module compares the measured temperature with the preset temperature and automatically adjusts the power supply of the heating element, increasing power at low temperatures and decreasing power or shutting down at high temperatures. The heating block cover plate 204 is sealed and insulated, and together with the heat insulation components, it maintains a constant and stable temperature while reducing energy consumption.

[0037] The gas to be tested enters smoothly and fills the gas chamber. When the laser beam passes through the gas chamber, it interacts with the gas molecules. The molecules selectively absorb the laser energy, and the degree of light intensity attenuation is positively correlated with the gas concentration. The laser is reflected back to the gas chamber by the four-dimensional adjustment stage reflector 22 along the original optical path, which doubles the propagation distance and improves the detection sensitivity of low-concentration gases. Finally, the reflected laser is captured by the laser receiving device.

[0038] The entire workflow is now complete, and anything not described in detail in this specification is existing technology known to those skilled in the art.

[0039] It should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0040] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A constant temperature gas chamber for NH3 gas detection, comprising a gas chamber body (1), wherein a laser emitting module (20) and a laser reflecting module (21) are respectively installed at both ends of the gas chamber body (1), and lens brackets (10) are provided at both openings of the gas chamber body (1), wherein a lens (17) is installed on the inner side of the lens brackets (10), and a sealing assembly and a heat insulation assembly are provided at the openings of the gas chamber body (1), characterized in that: A heating mechanism is provided on the outside of the main body of the air chamber (1); The heating mechanism includes two sets of heating blocks (2) that are locked and wrapped around the outside of the air chamber body (1) by screws. The two sets of heating blocks (2) are upper blocks and lower blocks respectively. The upper blocks and lower blocks are in an arc shape that fits the air chamber body (1) on opposite sides. The lower blocks and upper blocks are provided with top grooves (201) on opposite sides. A cover plate (204) is fixed by screws to cover the top grooves (201). The interior is also provided with multiple filling grooves (202) that are equidistantly distributed along the length of the top grooves (201). The top grooves (201) and filling grooves (202) are filled with thermally conductive silicone grease. A mica heating plate (203) covering the filling grooves (202) is installed in the top grooves (201). The mica heating plate (203) is in contact with the thermally conductive silicone grease.

2. The constant temperature gas chamber for NH3 gas detection according to claim 1, characterized in that: A side groove (206) is provided at the opposite edges of the upper and lower blocks, and a temperature sensor (207) is installed in the side groove (206).

3. The constant temperature gas chamber for NH3 gas detection according to claim 2, characterized in that: The upper and lower blocks are provided with wire openings (205) at opposite edges, which are respectively connected to the top groove (201) and the side groove (206) for the wires of the mica heating element (203) and the temperature sensor (207) to pass through.

4. The constant temperature gas chamber for NH3 gas detection according to claim 1, characterized in that: The heat insulation assembly includes heat insulation pads (8) for the air chamber tubes installed at the two openings of the air chamber body (1). The lens bracket (10) is located inside the heat insulation pads (8) for the air chamber tubes. A lens heat insulation ring (12) is installed on one side of the lens bracket (10). A concave surface is formed on one side of the heat insulation pads (8) for the air chamber tubes. The laser emitting module (20) and the laser reflecting module (21) are both installed in the corresponding concave surfaces. The heat insulation plate (18) is installed inside the laser emitting module (20) and the laser reflecting module (21) on the side close to the air chamber body (1).

5. A constant temperature gas chamber for NH3 gas detection according to claim 1, characterized in that: The sealing assembly includes a sealing ring (9) embedded in the two ports of the air chamber body (1). The sealing ring (9) is in contact with the corresponding lens bracket (10). The inner side of the lens bracket (10) has an annular edge (14). An annular groove (15) is provided on the annular edge (14). An elastic filler is provided in the annular groove (15). The lens (17) is in contact with the annular edge (14) and covers the annular groove (15).

6. A constant temperature gas chamber for NH3 gas detection according to claim 4, characterized in that: The lens bracket (10) is fixed to the air chamber body (1) by screws. The outer side of the lens heat insulation ring (12) has a groove (13) that matches the screws. The lens heat insulation ring (12) and the lens bracket (10) are fixed by screws.

7. A constant temperature gas chamber for NH3 gas detection according to claim 1, characterized in that: The upper sides of the heating block (2) are provided with U-shaped grooves (7) that are adapted to the smoke inlet and outlet of the gas chamber body (1).

8. A constant temperature gas chamber for NH3 gas detection according to claim 1, characterized in that: The lower block has two sets of half-grooves (4) on both sides, and positioning holes (5) are provided in the half-grooves (4). The upper block has upper grooves (6) on both sides that are opposite to the corresponding half-grooves (4).

9. A constant temperature gas chamber for NH3 gas detection according to claim 1, characterized in that: A filter assembly (22) and an ejector assembly (23) are installed on the outer side of the lower block of the heating block (2).

Images