Gas detection device for fiber bragg grating

Abstract

The invention relates to the technical field of gas detection, and particularly discloses a gas detection device for a fiber bragg grating, the gas detection device comprises a detection tube, a sampling tube and a detection unit, and the sampling tube has at least two states including an unfolded state and a contracted state. The detection pipe is of a three-layer structure composed of the inner pipe, the sound insulation pipe and the outer pipe, the sound insulation performance in the detection pipe can be greatly improved, the tail end of the sampling pipe is provided with a corresponding sealing piece and a sealing gasket, the tail end of the detection pipe is provided with a pipe cover, a magnetic block and other components, and when the sampling pipe is in a contraction state, the detection pipe is not prone to deformation. The opening of the detection tube is blocked by the tube cover, so that the sampling tube is completely accommodated in the detection tube to form a closed detection cavity, the outer wall of the detection cavity can isolate external sound, sound waves generated by the external sound are prevented from being transmitted to the microphone, and interference of the external sound on measurement of the concentration of carbon dioxide in the gas in the sampling tube can be avoided; and the detection precision is greatly improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of gas detection, and particularly relates to a gas detection device for fiber Bragg gratings. Background Art

[0002] Air contains common gases such as oxygen, carbon dioxide, and nitrogen. In areas where carbon dioxide gas accumulates, it can cause difficulty in breathing and is likely to harm the human body. Therefore, it is necessary to monitor the content of carbon dioxide gas in the air in real time.

[0003] An optical fiber is a fiber made of glass, quartz, or plastic. Optical fibers can be used in fields such as communication, light guiding, image conduction, medical treatment, and detection. When using an optical fiber to detect polluted gases, the concentration of the polluted gas can be calculated by measuring the loss value generated during the process of a light beam passing through the polluted gas. Specifically, the concentration of the gas is measured through the photoacoustic effect.

[0004] The photoacoustic effect is a term in physics. When a substance is irradiated with light with periodically modulated intensity, the phenomenon of generating mechanical waves occurs. When a certain medium is irradiated with light, due to the absorption of light by the medium, its internal temperature changes, which causes changes in the structure and volume of some regions within the medium; when a pulsed light source or a modulated light source is used, the rise and fall of the medium's temperature will cause the volume of the medium to expand and contract, and thus mechanical waves can be radiated outward.

[0005] Currently, the photoacoustic effect is mostly used for the detection of carbon dioxide concentration in gases. However, there are the following problems in the detection process using the above method:

[0006] First, when measuring the carbon dioxide concentration, the value of the carbon dioxide concentration is obtained by identifying the sound waves generated by the photoacoustic effect. However, during the detection process, the sound waves during the propagation of external sounds of the detection device will cause deviations in the results measured by the detection device, resulting in low measurement accuracy.

[0007] Second, if the detection device is not in a stable state during the detection process, the shaking of the detection device will cause the shaking of the position of carbon dioxide inside it, which will reduce the measurement accuracy of the detection device. To solve the above problems, therefore, the present application proposes a gas detection device for fiber Bragg gratings. Summary of the Invention

[0008] The purpose of the present invention is to provide a gas detection device for fiber Bragg gratings to solve the problems raised in the above background art.

[0009] To achieve the above object, the present invention provides the following technical solution. A gas detection device for fiber Bragg gratings includes a detection tube, a sampling tube, and a detection unit. The sampling tube has at least two states including an unfolded state and a contracted state. When the sampling tube is in the contracted state, the sampling tube is received inside the detection tube. The detection unit is used to measure the content of carbon dioxide in the sampling tube.

[0010] The detection tube includes an inner tube, a sound insulation tube, and an outer tube. The inner tube, the sound insulation tube, and the outer tube are arranged in sequence, and a sound insulation cavity that is evacuated is provided inside the sound insulation tube.

[0011] A support assembly is provided on the detection tube. The support assembly has a support state and a retracted state. When the detection tube is in the support state, the detection tube can be stably supported.

[0012] Preferably, the detection unit includes an infrared emitter, an infrared filter, a microphone, and a control module.

[0013] Preferably, the detection unit further includes a display screen. The display screen is connected to the control module and is used to display the measured value of the carbon dioxide concentration in the sampling tube.

[0014] Preferably, a guiding groove is provided inside the detection tube. A guiding block is installed on the outer wall of the sampling tube. The guiding block is slidably connected to the guiding groove, and an intercepting plate is provided inside the guiding groove.

[0015] Preferably, a sealing member is provided at one end of the sampling tube away from the detection tube. The sealing member is detachably connected to the sampling tube by bolts. A sealing groove is provided inside the sealing member, and a sealing gasket is clamped inside the sealing groove. When the sampling tube is in the contracted state, the sealing gasket abuts against the inner wall of the detection tube.

[0016] Preferably, a tube cover is provided on the detection tube. A magnetic block is installed on the tube cover, and an installation groove is provided at the position of the detection tube corresponding to the magnetic block. An adsorption plate is inserted into the installation groove.

[0017] Preferably, the support assembly includes a plurality of legs. The legs are provided on the detection tube. The legs are connected to a mounting seat, and the mounting seat is installed on the outer wall of the detection tube. The legs are connected to a support plate, and a first connecting rod is inserted into one end of the support plate away from the legs.

[0018] Preferably, the first connecting rod is inserted into a transverse frame. A transverse groove is provided inside the transverse frame. The first connecting rod and the transverse groove can slide relative to each other, and the transverse frame is connected to a lifting frame.

[0019] Preferably, the lifting frame is connected to a telescopic rod for pushing the lifting frame to move up and down, and a second connecting rod is inserted into the lifting frame.

[0020] Preferably, a vertical frame is provided at the top of the detection tube, a vertical groove is provided inside the vertical frame, and the second connecting rod is slidably connected to the vertical groove.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] First, by setting the detection tube as a three-layer structure composed of an inner tube, a sound insulation tube, and an outer tube, the present invention can greatly improve the sound insulation performance inside the detection tube. Sealing members and gaskets are provided at the end of the sampling tube, and components such as a tube cap and a magnet are provided at the end of the detection tube. When the sampling tube is in a contracted state, the opening of the detection tube can be blocked by the tube cap, so that the sampling tube can be completely received into the detection tube to form a sealed detection cavity. The outer wall of the detection cavity can isolate external sounds, prevent the sound waves generated by external sounds from being transmitted to the microphone, and avoid the interference of external sounds on the measurement of the carbon dioxide concentration in the gas inside the sampling tube, thus greatly improving the detection accuracy.

[0023] Second, the support assembly of the present invention has a support state and a retracted state. When the support assembly switches states, the telescopic rod can be activated to push the lifting frame to move up and down. During the up and down movement of the lifting frame, the second connecting rod inside it can only move vertically up and down under the guidance of the vertical groove. When the lifting frame moves vertically up and down, it can drive the four transverse frames connected to it to move. During the movement of the first connecting rod inserted into the transverse groove in the transverse frame along the transverse groove, the support legs can be pulled to rotate around the mounting seat through the support plate, so that the support legs can be switched between the support state and the retracted state. In the support state, the detection tube can be supported to keep the support tube placed stably, avoiding the inaccurate detection of the carbon dioxide concentration in the sampling tube caused by the shaking of the detection tube. Description of the Drawings

[0024] Figure 1 The first structural schematic diagram of the gas detection device for fiber Bragg gratings in the present invention.

[0025] Figure 2 The second structural schematic diagram of the gas detection device for fiber Bragg gratings in the present invention.

[0026] Figure 3 The third structural schematic diagram of the gas detection device for fiber Bragg gratings in the present invention.

[0027] Figure 4 The first internal structural schematic diagram of the gas detection device for fiber Bragg gratings in the present invention.

[0028] Figure 5 The second internal structural schematic diagram of the gas detection device for fiber Bragg gratings in the present invention.

[0029] Figure 6This is the third internal structure schematic diagram of the gas detection device for fiber Bragg gratings in the present invention.

[0030] In the figure: 1. Detection tube; 101. Inner tube; 102. Sound insulation tube; 103. Outer tube; 104. Adsorption plate; 105. Guide groove; 106. Intercepting plate; 2. Sampling tube; 201. Air inlet hole; 202. Guide block; 3. Infrared emitter; 4. Infrared filter; 5. Microphone; 6. Seal; 7. Gasket; 8. Pipe cap; 9. Magnet; 10. Control module; 11. Display screen; 12. Leg; 13. Mounting seat; 14. Support plate; 15. Horizontal frame; 16. Lifting frame; 17. Telescopic rod; 18. Vertical frame. Detailed implementation manners

[0031] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0032] Referring to Figures 1 - 6 , a gas detection device for fiber Bragg gratings includes a detection tube 1, a sampling tube 2, and a detection unit. The detection tube 1 and the sampling tube 2 are combinedly connected. The sampling tube 2 has at least two states including an unfolded state and a contracted state. When the sampling tube 2 is in the unfolded state, the sampling tube 2 extends out of the detection tube 1, and the air inlet hole 201 in the detection tube 1 is communicated with the external air. When the sampling tube 2 is in the contracted state, the sampling tube 2 is received inside the detection tube 1. The detection unit is used to measure the content of carbon dioxide in the sampling tube 2, and the detection of the carbon dioxide concentration in the gas in the sampling tube 2 is carried out inside the detection tube 1. An optical fiber is a fiber made of glass, quartz or plastic, and optical fibers can be used in fields such as communication, light conduction, image conduction, medical treatment and detection. When using an optical fiber to detect polluted gas, the concentration of the polluted gas can be calculated by measuring the loss value generated during the process of a light beam passing through the polluted gas. Specifically, the concentration of the gas is measured through the photoacoustic effect.

[0033] Specifically, the detection unit includes an infrared emitter 3, an infrared filter 4, a microphone 5, and a control module 10. The infrared emitter 3 is used to emit infrared rays. The infrared filter 4 is used to filter the infrared rays emitted by the infrared emitter 3 to make the infrared rays more concentrated. When the sampling tube 2 is in a contracted state, the infrared rays emitted by the infrared emitter 3, after passing through the infrared filter 4, shine on the gas inside the sampling tube 2. When the infrared rays shine on carbon dioxide inside the sampling tube 2, sound waves will be generated due to the photoacoustic effect. The microphone 5 can amplify the received sound waves, and the control module 10 continuously receives and processes the amplified sound waves to judge the concentration of carbon dioxide inside the sampling tube 2. In this way, the measurement of the carbon dioxide concentration inside the sampling tube 2 can be completed.

[0034] More specifically, the detection unit further includes a display screen 11. The display screen 11 is connected to the control module 10 and is used to display the measured value of the carbon dioxide concentration inside the sampling tube 2. By setting the display screen 11 that can display the measured value, it is more convenient for the detection personnel to view the detection results.

[0035] In order to make the movement of the detection tube 1 and the sampling tube 2 more stable during their relative movement, a guiding groove 105 is provided inside the detection tube 1, a guiding block 202 is installed on the outer wall of the sampling tube 2, the guiding block 202 is slidably connected to the guiding groove 105, and an intercepting plate 106 is provided inside the guiding groove 105. The intercepting plate 106 is used to limit the maximum distance of the movement of the guiding block 202 to prevent the sampling tube 2 from completely detaching from the detection tube 1.

[0036] By measuring the sound waves generated by the acoustic wave effect, the concentration of carbon dioxide inside the sampling tube 2 is measured. In order to avoid the influence of external sounds, the detection tube 1 includes an inner tube 101, a sound insulation tube 102, and an outer tube 103. The inner tube 101, the sound insulation tube 102, and the outer tube 103 are arranged in sequence, and a sound insulation cavity that is evacuated is provided inside the sound insulation tube 102.

[0037] Specifically, a seal 6 is provided at one end of the sampling tube 2 away from the detection tube 1. The seal 6 is detachably connected to the sampling tube 2 by bolts. A seal groove is provided inside the seal 6, and a gasket 7 is clamped inside the seal groove. When the sampling tube 2 is in a contracted state, the gasket 7 abuts against the inner wall of the detection tube 1;

[0038] More specifically, a tube cover 8 is provided on the detection tube 1, a magnetic block 9 is installed on the tube cover 8, and a mounting groove is provided at the position of the detection tube 1 corresponding to the magnetic block 9, and an adsorption plate 104 is inserted into the mounting groove.

[0039] By setting the detection tube 1 as a three-layer structure composed of an inner tube 101, a sound insulation tube 102, and an outer tube 103, the sound insulation performance inside the detection tube 1 can be significantly improved. Corresponding seals 6 and gaskets 7 are provided at the end of the sampling tube 2, and components such as a tube cap 8 and a magnet 9 are provided at the end of the detection tube 1. When the sampling tube 2 is in a contracted state, the opening of the detection tube 1 can be blocked by the tube cap 8, so that the sampling tube 2 can be completely received into the detection tube 1. The detection tube and other components together form a closed detection cavity, and the outer wall of the detection cavity can isolate external sounds, preventing the sound waves generated by external sounds from being transmitted to the microphone 5, and avoiding interference from external sounds on the measurement of the carbon dioxide concentration of the gas inside the sampling tube 2, thus significantly improving the detection accuracy.

[0040] In order to improve the overall stability of the detection tube 1 during the detection process and prevent it from shaking (if the detection tube 1 shakes, the position of the gas inside it will change significantly, which will cause deviations in the detection results of the carbon dioxide concentration inside it), a support component is provided on the detection tube 1. The support component has a support state and a retracted state. When the detection tube 1 is in the support state, the detection tube 1 can be stably supported.

[0041] It should be noted that a number of legs 12 are provided on the detection tube 1, and the legs 12 are connected to a mounting base 13. Specifically, the legs 12 are rotatably connected to the mounting base 13, and the mounting base 13 is installed on the outer wall of the detection tube 1. The legs 12 are connected to a support plate 14, and a first connecting rod is inserted into one end of the support plate 14 away from the legs 12. The first connecting rod is inserted into a transverse frame 15, and a transverse groove is provided inside the transverse frame 15. The first connecting rod and the transverse groove can slide relative to each other. The transverse frame 15 is connected to a lifting frame 16, and the lifting frame 16 is connected to four transverse frames 15. During its up and down movement, it can drive the four lifting frames 16 to move synchronously.

[0042] Specifically, the lifting frame 16 is connected to a telescopic rod 17 for pushing the lifting frame 16 up and down. A second connecting rod is inserted into the lifting frame 16, and a vertical frame 18 is provided at the top of the detection tube 1. A vertical groove is provided inside the vertical frame 18, and the second connecting rod is slidably connected to the vertical groove.

[0043] Working principle:

[0044] By setting the detection tube 1 as a three-layer structure composed of an inner tube 101, a sound insulation tube 102, and an outer tube 103, the sound insulation performance inside the detection tube 1 can be greatly improved. Corresponding seals 6 and gaskets 7 are provided at the end of the sampling tube 2, and components such as a tube cap 8 and a magnet 9 are provided at the end of the detection tube 1. When the sampling tube 2 is in a contracted state, the opening of the detection tube 1 can be blocked by the tube cap 8, so that the sampling tube 2 can be completely received into the detection tube 1 to form a closed detection cavity. The outer wall of the detection cavity can isolate external sounds, avoid the sound waves generated by external sounds from being transmitted to the microphone 5, and can avoid the interference of external sounds on the measurement of the carbon dioxide concentration in the gas inside the sampling tube 2, greatly improving the detection accuracy.

[0045] When the telescopic rod 17 is activated, it can push the lifting frame 16 to move up and down. During the up and down movement of the lifting frame 16, the second connecting rod inside it can only move vertically up and down under the guidance of the vertical groove. When the lifting frame 16 moves vertically up and down, it can drive the four transverse frames 15 connected to it to move. When the first connecting rod inserted into the transverse groove in the transverse frame 15 moves along the transverse groove, it can pull the support leg 12 to rotate around the mounting seat 13 through the support plate 14, so that the support leg 12 can be switched between the support state and the retracted state. In the support state, it can support the detection tube 1 and place the support tube 1 stably, avoiding the inaccurate detection of the carbon dioxide concentration in the sampling tube 2 caused by the shaking of the detection tube 1.

[0046] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A gas detection device for fiber Bragg grating, characterized in that: The invention comprises a detection tube (1), a sampling tube (2), and a detection unit, wherein the sampling tube (2) has at least two states including an expanded state and a contracted state, and when the sampling tube (2) is in the contracted state, the sampling tube (2) is retracted into the detection tube (1), and the detection unit is used to measure the content of carbon dioxide in the sampling tube (2); The detection tube (1) comprises an inner tube (101), a soundproof tube (102), and an outer tube (103); the inner tube (101), the soundproof tube (102), and the outer tube (103) are arranged in sequence, and a soundproof cavity which is evacuated to a vacuum is provided in the soundproof tube (102); The detection tube (1) is provided with a support component, and the support component has a supporting state and a retracted state. When the detection tube (1) is in the supporting state, the detection tube (1) can be stably supported.

2. A gas detection device for fiber Bragg grating according to claim 1, characterized in that: The detection unit comprises an infrared transmitter (3), an infrared filter (4), a microphone (5), and a control module (10).

3. A gas detection device for fiber Bragg grating according to claim 2, characterized in that: The detection unit further comprises a display screen (11), the display screen (11) being connected to the control module (10), and the display screen (11) being used to display the measured carbon dioxide concentration value in the sampling tube (2).

4. A gas detection device for fiber Bragg grating according to claim 1, characterized in that: The detection tube (1) is provided with a guide groove (105), the outer wall of the sampling tube (2) is provided with a guide block (202), the guide block (202) is slidably connected to the guide groove (105), and an interception plate (106) is provided in the guide groove (105).

5. A gas detection device for fiber Bragg grating according to claim 1, characterized in that: A sealing member (6) is provided at one end of the sampling tube (2) away from the detection tube (1); the sealing member (6) and the sampling tube (2) are detachably connected via bolts; a sealing groove is provided in the sealing member (6); a sealing gasket (7) is clamped in the sealing groove; when the sampling tube (2) is in a contracted state, the sealing gasket (7) abuts against the inner wall of the detection tube (1).

6. A gas detection device for fiber Bragg grating according to claim 5, characterized in that: The detection tube (1) is provided with a tube cover (8), a magnetic block (9) is installed on the tube cover (8), and a mounting groove is provided at a position of the detection tube (1) corresponding to the magnetic block (9), and an adsorption plate (104) is inserted into the mounting groove.

7. A gas detection device for fiber Bragg grating according to claim 1, characterized in that: The support assembly comprises a plurality of legs (12), the legs (12) being arranged on the detection tube (1), the legs (12) being connected to a mounting seat (13), the mounting seat (13) being mounted on an outer wall of the detection tube (1), the legs (12) being connected to a support plate (14), and a first connecting rod being inserted into one end of the support plate (14) away from the legs (12).

8. A gas detection device for fiber Bragg grating according to claim 7, characterized in that: The first connecting rod is plugged with a transverse frame (15), a transverse groove is arranged in the transverse frame (15), the first connecting rod and the transverse groove can slide relative to each other, and the transverse frame (15) is connected with a lifting frame (16).

9. A gas detection device for fiber Bragg grating according to claim 8, characterized in that: The lifting frame (16) is connected to a telescopic rod (17) for pushing the lifting frame (16) to move up and down, and a second connecting rod is inserted into the lifting frame (16).

10. A gas detection device for fiber Bragg grating according to claim 9, characterized in that: A vertical frame (18) is arranged on the top of the detection tube (1), a vertical groove is arranged inside the vertical frame (18), and the second connecting rod is slidably connected to the vertical groove.

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