Extremely early fire hazard early warning system based on multispectral detection

Abstract

The invention discloses an extremely early fire hazard early warning system based on multispectral detection. The system comprises a box body, an air blower, an air booster pump, a heat loss particle detection module and an exhaust module, the heat loss particle detection module comprises an infrared light source, a detection chamber and a photodiode, an air outlet of the detection chamber is connected with an air inlet of the exhaust module, an exhaust valve is mounted on the exhaust module, an air pressure sensor is mounted on the detection chamber, an air inlet of the detection chamber is connected with an air outlet of the air booster pump, and the infrared light source is mounted on the detection chamber. And the photodiode is mounted on the detection chamber so as to measure the concentration of heat loss particles in the detection chamber after the air pressure in the detection chamber reaches a set value. The concentration of heat loss particles in the detection chamber is improved, the reliability of the detection result is improved in combination with multispectral detection, the abnormal concentration of the heat loss particles can be detected in time, fire early warning can be carried out in an extremely early stage, and the comprehensive disaster risk is reduced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of fire monitoring facilities, and more particularly relates to an extremely early fire hazard early warning system based on multi-spectral detection. BACKGROUND

[0002] A cloud chamber is a device that uses the condensation phenomenon of ions in supersaturated vapor to observe the trajectory of charged particles. Its core principle is: when high-energy particles (such as alpha and beta particles) pass through a closed container filled with alcohol or ether saturated vapor, ions will be generated on the path, and these ions become the core of vapor condensation, forming tiny droplets, which then appear as visible fog-like tracks under light. By analyzing the length, density and bending degree of the track in the magnetic field, the properties, types and concentration of the detected particles can be inferred.

[0003] Modern cloud chamber technology, such as thermal overload detectors, has the following applications in fire detection: 1) Active sampling and analysis: collect air samples and filter them into a cloud chamber to analyze the concentration of thermal damage particles and provide early warning in the physical burning stage. 2) Electron escape detection: detect charged particles released by combustible materials before carbonization, and combine circuit signal processing to achieve accurate alarm.

[0004] However, cloud chamber detection technology, which relies heavily on the vapor in the cloud chamber, has problems in quantitatively detecting the concentration of thermal damage particles in a fire: when estimating ion concentration by droplet density, the detection results are significantly affected by factors such as vapor supersaturation, temperature, and pressure, resulting in significant fluctuations and reduced reliability, making it difficult to accurately determine the occurrence of a fire, especially in the early stages of fire hazard investigation, making it difficult to accurately warn of fire hazards. SUMMARY

[0005] To overcome the above defects or improvement needs of the prior art, the present application provides an extremely early fire hazard early warning system based on multi-spectral detection, which detects the concentration of thermal damage particles through a detection chamber with infrared light and a photodiode inside the detection chamber, making detection accurate, convenient, and high-precision, and solving the problem of excessive reliance on internal vapor in traditional cloud chamber detection.

[0006] To achieve the above purpose, according to the present application, an extremely early fire hazard early warning system based on multi-spectral detection is provided, comprising a box body and a blower, an air booster pump, a thermal damage particle detection module, and an exhaust module installed in the box body, characterized in that: The box body is provided with an air inlet and an air outlet, and the air inlet of the blower is arranged corresponding to the air inlet of the box body to draw gas outside the box body into the box body; The thermal damage particle detection module comprises an infrared light source, a detection chamber and a photodiode, the detection chamber is provided with an air inlet and an air outlet, the air outlet of the detection chamber is connected to the air inlet of the exhaust module, the exhaust module is provided with an exhaust valve, and the air inlet of the detection chamber is connected to the air outlet of the air booster pump, so that the air pressure in the inner cavity of the detection chamber reaches a set value through the pressure boosting of the air booster pump. The infrared light source can emit infrared light of N wavelengths, and the number of photodiodes is also N, each photodiode detects the concentration of thermal damage particles in an infrared light environment of one wavelength, and N≥2.

[0007] Preferably, N=2, two independent light paths are detected by two light spectra to obtain the concentration of thermal damage particles, the infrared light source comprises two lasers, namely laser A and laser B, and two photodiodes detect infrared light of the working wavelength of laser A and laser B, respectively.

[0008] Preferably, the two photodiodes are respectively a silicon photodiode and an indium gallium arsenide diode; the silicon photodiode detects infrared light of 960nm wavelength emitted by the infrared light source, and the indium gallium arsenide diode detects infrared light of 1550nm wavelength emitted by the infrared light source.

[0009] Preferably, one of the detection light paths is based on the scattering principle, and the concentration of thermal damage particles is determined by detecting the scattering light intensity caused by thermal damage particles; the stronger the scattering light, the higher the concentration of thermal damage particles; the other detection light path is based on the transmission principle, and the concentration of thermal damage particles is determined by detecting the transmission light intensity of the straight-line propagation through the thermal damage particles; the stronger the transmission light, the lower the concentration of thermal damage particles.

[0010] Preferably, an air valve for preventing gas backflow is installed at the air inlet of the air booster pump.

[0011] Preferably, the air pressure in the detection chamber reaches 0.1MPa~0.15MPa, and the photodiode measures the concentration of thermal damage particles in the detection chamber.

[0012] Preferably, an air pressure sensor is installed on the detection chamber to obtain the air pressure in the inner cavity of the detection chamber.

[0013] Preferably, the photodiode is installed on the detection chamber and extends into the detection chamber to measure the concentration of thermal damage particles in the detection chamber when the air pressure in the detection chamber reaches a set value.

[0014] Preferably, the air inlet of the air blower is connected to the air inlet of the box through a pipeline, and the air inlet of the box is provided with an air volume detection module to detect whether the air volume is normal.

[0015] Preferably, an alarm is further included to perform an alarm process when the thermal damage particle concentration reaches a set value and / or the thermal damage particle concentration rising speed exceeds a preset threshold.

[0016] Overall, compared with the prior art, the above technical solutions conceived by the present application can achieve the following beneficial effects: 1) The early-stage fire hazard early warning system based on multi-spectrum detection of the present application can improve the concentration of thermal damage particles inside the detection chamber by drawing air into the detection chamber of the thermal damage particle detection module through the air blower and air booster pump, improve the reliability of the detection results by combining multi-spectrum detection, timely detect abnormal thermal damage particle concentration, and perform early-stage fire warning to avoid the spread of electrical fire and reduce the overall disaster risk.

[0017] 2) The early-stage fire hazard early warning system based on multi-spectrum detection of the present application can let external gas enter the device through the air blower and air booster pump, and draw gas into the detection chamber to make the air pressure of the inner cavity of the detection chamber reach a set value, ensure that there is enough gas in the detection chamber, and make the thermal damage particle concentration in the detection chamber also reach a certain value, thereby ensuring the accuracy of thermal damage particle concentration detection.

[0018] 3) The preferred scheme of the present application combines multi-spectrum scattering-transmission fusion detection to obtain high-precision detection in a wide linear range and realize early-stage accurate fire warning. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a perspective view of the present application; Figure 2 is an exploded view of the present application; Figure 3 is a schematic diagram of the thermal damage particle detection module based on scattering principle in the present application; Figure 4 is a schematic diagram of the thermal damage particle detection module based on transmission principle in the present application; Figure 5 is a schematic diagram of the thermal damage particle detection module based on scattering-transmission fusion detection in the present application. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and do not limit the present application. In addition, the technical features involved in each embodiment of the present application described below can be combined with each other as long as they do not conflict with each other.

[0021] Reference Figures 1-5The utility model relates to a kind of early fire hazard warning system based on multispectral detection, including box 5 and installation in box 5 air blower 1, air booster pump 2, heat loss particle detection module 3 and exhaust module 4.

[0022] The box 5 is provided with air inlet and air outlet, the air inlet of the air blower 1 is arranged corresponding to the air inlet of the box 5, to suck the gas outside the box 5 into the box 5;Air blower 1 sucks the air outside the box 5 into the box 5. Because the air volume of air blower 1 is relatively large, air blower 1 and air booster pump 2 are not directly connected together by pipeline, that is, the two are separated, the gas sucked into the box 5 by air blower 1 is not directly into air booster pump 2, but a large part is discharged from the air outlet of the box 5, therefore, the gas compressed by subsequent air booster pump 2 is only a small part of the gas sucked into the box 5 by air blower 1, and the gas detected by heat loss particle detection module 3 is also only a small part of the gas sucked into the box 5 by air blower 1.

[0023] The heat loss particle detection module 3 includes infrared light source 31, detection chamber 32 and photodiode 33, the air outlet of the detection chamber 32 is preferably connected to the air inlet of the exhaust module 4 by pipeline, the detection chamber 32 is provided with air pressure sensor for obtaining the air pressure of the inner cavity of the detection chamber 32, the exhaust module 4 is provided with exhaust valve, and the air inlet of the detection chamber 32 is connected to the air outlet of the air booster pump 2 by pipeline, so that the air booster pump 2 sucks the gas into the detection chamber 32 to make the air pressure of the inner cavity of the detection chamber 32 reach the set value, the infrared light source 31 is installed on the detection chamber 32 for emitting infrared light 34 into the detection chamber 32.

[0024] The photodiode 33 is installed on the detection chamber 32 and extends into the detection chamber 32, reducing light energy loss and improving detection sensitivity, so that the infrared light in the detection chamber 32 can irradiate on the photodiode 33, after the air pressure in the detection chamber 32 reaches the set value, the photodiode 33 measures the concentration of heat loss particles in the detection chamber 32, the photodiode 33 is connected to the controller, and the data detected by the photodiode 33 is analyzed and processed by the controller, and when the heat loss particle concentration reaches the set value and / or the heat loss particle concentration rises speed exceeds the preset threshold value, alarm processing is carried out.

[0025] The photodiode 33 detects the concentration of heat loss particles in the infrared light environment, so that the concentration of heat loss particles detected by the photodiode 33 is accurate. Without infrared light, the photodiode 33 cannot detect heat loss particles. When the heat loss particle concentration rising speed exceeds the preset threshold value, alarm processing is carried out.

[0026] After the photodiode 33 finishes detection, the exhaust valve is opened to exhaust the gas in the detection chamber 32.

[0027] Further, the infrared light source 31 can emit infrared light of N wavelengths, and correspondingly, the number of photodiodes 33 is also N, so as to form a multi-spectral infrared environment for the photodiodes 33 to detect, and the concentration of thermal damage particles is determined by comprehensive analysis of infrared waves of N different wavelengths, where N≥2. Each photodiode 33 detects under an infrared light environment of one wavelength. Multi-spectrum is used for multi-path independent light path detection to obtain the concentration of thermal damage particles, thereby improving the reliability of the detection result.

[0028] In a preferred embodiment, taking N=2 as an example, two light paths are used for two-path independent light path detection to obtain the concentration of thermal damage particles. The infrared light source 31 includes two lasers, namely laser A and laser B. Two photodiodes 33 detect infrared light of the working wavelength of laser A and laser B, respectively.

[0029] In a specific preferred embodiment, one detection light path is based on the scattering principle, and the concentration of thermal damage particles is determined by detecting the scattering light intensity caused by the thermal damage particles. The stronger the scattering light, the higher the concentration of thermal damage particles. The other detection light path is based on the transmission principle, and the concentration of thermal damage particles is determined by detecting the transmission light intensity that propagates in a straight line through the thermal damage particles. The stronger the transmission light, the lower the concentration of thermal damage particles. The thermal damage particle detection based on the scattering principle has high sensitivity, but the linear detection range is difficult to cover the case of high concentration of thermal damage particles, which makes the detection result of the present application inaccurate and cannot accurately realize early fire hazard warning. The thermal damage particle detection based on the transmission principle has a linear detection range covering high concentration of thermal damage particles, up to 300 mg / m³. However, its measurement accuracy at low concentration is limited, and it cannot realize early fire hazard warning. The early fire hazard warning system based on multi-spectral detection provided by the present application is based on multi-spectral scattering-transmission fusion detection, and the linear range covers 0.01-300 mg / m³, realizing wide linear range high-precision detection of thermal damage particles. On the one hand, the detection limit of thermal damage particles is reduced, and on the other hand, it is suitable for high concentration detection. In combination with the pressurization detection, high-precision detection of ultra-low concentration thermal damage particles is realized, the data reliability is improved, and early accurate fire warning is realized.

[0030] The detection light path based on the scattering principle is orthogonal to the main optical axis of the infrared light source 31 and the photodiode 33, as shown in Figure 3 The detection light path based on the transmission principle is coaxial with the infrared light source 31 and the photodiode 33, as shown in Figure 4 The detection light path based on scattering-transmission fusion detection in the preferred embodiment includes at least two independent light paths, as shown in Figure 5As shown, the infrared light source 31 emits infrared light of two wavelengths, such as 960 nm infrared light and 1550 nm infrared light; the orthogonally arranged photodiode 33 detects the intensity of one of the infrared lights for detection based on scattering principle, and the coaxially arranged photodiode 33 detects the intensity of the other infrared light for detection based on transmission principle.

[0031] The photodiode 33 can adopt a silicon photodiode and an indium gallium arsenide diode, and the silicon photodiode preferably has an optimal working state in an infrared environment with an infrared light wavelength of 960 nm; the indium gallium arsenide diode preferably has an optimal working state in an infrared environment with an infrared light wavelength of 1550 nm.

[0032] If the infrared light source 31 emits infrared light of 960 nm wavelength to fill the entire detection chamber 32, a photodiode 33 with a working wavelength of 960 nm can be correspondingly used to detect the concentration of heat-damaged particles. If the infrared light source 31 emits infrared light of 1550 nm wavelength to fill the entire detection chamber 32, a photodiode 33 with a working wavelength of 1550 nm can be correspondingly used to detect the concentration of heat-damaged particles.

[0033] In an infrared environment with a wavelength of 960 nm or 1550 nm, the photodiode 33 with a working wavelength of 960 nm or 1550 nm can respectively detect the concentration data of heat-damaged particles, and the emitted data is an analog signal, which is converted into a digital signal by an AD module and recognized by a controller to obtain the concentration data of heat-damaged particles.

[0034] The photodiode 33 of the present application preferably adopts a silicon photodiode produced by Hamamatsu with a model number of S2386-44K, which has an optimal working wavelength of 960 nm (i.e., has an optimal working state in an infrared environment with an infrared light of 960 nm), corresponds to the infrared light source 31 emitting infrared light of 960 nm wavelength, and is used to detect the concentration of heat-damaged particles in the detection chamber 32 filled with infrared light of 960 nm wavelength. Meanwhile, the photodiode 33 preferably adopts an indium gallium arsenide photodiode produced by Hamamatsu with a model number of G8370-83, which has an optimal working wavelength of 1550 nm (i.e., has an optimal working state in an infrared environment with an infrared light of 1550 nm), corresponds to the infrared light source 31 emitting infrared light of 1550 nm wavelength, and is used to detect the concentration of heat-damaged particles in the detection chamber 32 filled with infrared light of 1550 nm wavelength.

[0035] Two photoelectric diodes 33 are silicon photoelectric diode A and indium gallium arsenide photoelectric diode B respectively, the working wavelength of silicon photoelectric diode A is 960nm, and the working wavelength of indium gallium arsenide photoelectric diode B is 1550nm. Laser A emits infrared light of 960nm wavelength, and silicon photoelectric diode A can detect the concentration of heat-damaged particles in the environment filled with 960nm wavelength infrared light in the detection chamber. Laser B emits infrared light of 1550nm wavelength, and indium gallium arsenide photoelectric diode B can detect the concentration of heat-damaged particles in the environment filled with 1550nm wavelength infrared light in the detection chamber.

[0036] The specific working process of laser A, laser B, silicon photoelectric diode A and indium gallium arsenide photoelectric diode B is as follows: Laser A and silicon photoelectric diode A are a group of detection units, laser B and indium gallium arsenide photoelectric diode B are another group of detection units, and the two groups of detection units work independently. After the air booster pump completes air extraction and the pressure of the detection chamber reaches the set value, laser A emits 960nm spectrum for the first time, and silicon photoelectric diode A detects the concentration of heat-damaged particles; laser B emits 1550nm spectrum for the second time, and indium gallium arsenide photoelectric diode B detects the concentration of heat-damaged particles. The two groups of detection units respectively detect the concentration of heat-damaged particles in the detection chamber once. The software algorithm analyzes and corrects according to the two detection results to obtain the accurate concentration for judgment.

[0037] Further, an air valve 21 for preventing gas backflow is installed at the air inlet of the air booster pump 2, which can adopt a check valve, a one-way valve or a non-return valve to prevent air from flowing back from the air booster pump 2 when the air booster pump 2 is working. The air valve 21 is closed when the air booster pump 2 compresses air to prevent air backflow, and is opened when the air booster pump 2 inhales air.

[0038] There are also some sheet metal parts 9 in the box 5 for fixing the heat-damaged particle detection module 3, the exhaust module 4, the air valve 21 and other components.

[0039] Further, the photoelectric diode 33 measures the concentration of heat-damaged particles in the detection chamber 32 when the air pressure in the detection chamber 32 reaches 0.1MPa-0.15MPa, preferably more than 1 standard atmosphere. When the air pressure in the detection chamber 32 is lower than 0.1MPa, it indicates that there is air leakage or air pipe damage between the air booster pump 2 and the detection chamber 32. When air leakage or air pipe damage occurs, it cannot guarantee that the gas in the detection chamber is extracted from the target position through the pipeline, and the current installation location environment gas will be mixed, thereby affecting the accuracy of the detection result.

[0040] Further, the air inlet of the air blower 1 is connected to the air inlet of the box 5 through a pipeline, and a wind volume detection module is arranged at the air inlet of the box 5 to detect whether the wind volume is normal, and whether the pipeline is blocked after long time work, and when the wind volume is detected to be lower than a certain value, the machine sends an alarm.

[0041] Further, the photodiode 33 is connected to the display device 6 through a wire to display the thermal damage particle concentration on the display device 6, so that the thermal damage particle concentration can be directly and intuitively understood, and the display device 6 has a 9-inch capacitive touch screen.

[0042] Further, the air outlet of the exhaust module 4 is connected to the air inlet of the temperature and humidity detection module 7 through a pipeline to detect the temperature and humidity of the outgoing gas and provide a reference for fire warning.

[0043] The working voltage of each electrical device of the present application can be DC 24V, and the working current is less than 2A.

[0044] The working process of the present application is as follows: The equipment is powered on, the air blower 1 works, and the air is sucked from the air inlet of the box 5 through a pipeline.

[0045] The air booster pump 2 compresses the air in the box 5 into the detection chamber 32 of the thermal damage particle detection module 3, and when the air pressure in the inner cavity of the detection chamber 32 reaches a certain value, the compression is paused, and then the photodiode 33 of the thermal damage particle module measures the concentration of thermal damage particles in the compressed gas in the detection chamber 32, and the concentration is fed back to the display device 6 in real time, and when the concentration reaches a certain value, an alarm will be sent.

[0046] The exhaust valve of the exhaust module 4 is closed during the air compression by the air booster pump 2 and the detection of the thermal damage particle module to prevent air leakage, and the exhaust valve of the exhaust module 4 is opened after the detection of the thermal damage particle module to exhaust the air in the detection chamber 32.

[0047] All signal input terminals of the present application are on the serial port module, and the whole machine is powered through the serial port module.

[0048] The application can realize 24h all-day operation of the whole machine, and all modules work after power-on, and the core action is mainly air compression pump compression air-thermal loss particle module detection-exhaust, which repeats such actions.

[0049] The upper plate and the lower plate of the box body 5 of the application are respectively reserved with outlet ports, and actual installation is selected according to requirements.

[0050] The embodiment does not use a steam cloud chamber, but directly draws in air for detection, avoids interference due to steam state control, and improves the stability and reliability of detection, in order to make up for the sensitivity drop caused by the inapplicability of the steam cloud chamber, adopts a pressurization strategy to improve the concentration of thermal loss particles in the cavity, cooperates with multi-spectrum detection to cover a large enough detection range, and realizes early hidden danger early warning.

[0051] Those skilled in the art can easily understand that the above description is only a preferred embodiment of the application, and is not used to limit the application, and any modification, equivalent replacement and improvement made within the spirit and principle of the application should be included in the protection scope of the application.

Claims

1. A very early fire hazard warning system based on multispectral detection, comprising a housing and a blower, an air booster pump, a heat damage particle detection module, and an exhaust module installed therein, characterized in that: The box body is provided with an air inlet and an air outlet, and the air inlet of the blower is arranged corresponding to the air inlet of the box body to draw the air outside the box body into the box body; The thermal damage particle detection module includes an infrared light source, a detection chamber, and a photodiode. The detection chamber is provided with an air inlet and an air outlet. The air outlet of the detection chamber is connected to the air inlet of the exhaust module. The exhaust module is equipped with an exhaust valve. The air inlet of the detection chamber is connected to the air outlet of the air booster pump, so that the air pressure in the inner cavity of the detection chamber reaches a set value through the pressurization of the air booster pump. The infrared light source can emit infrared light of N wavelengths, and the number of the photodiodes is also N. Each photodiode detects the concentration of heat-damaged particles under an infrared light environment of one wavelength, wherein N≥2.

2. The very early fire hazard warning system based on multispectral detection according to claim 1, characterized in that: N=2, two spectra are used to perform two independent optical path detections to obtain the concentration of thermally damaged particles. The infrared light source includes two lasers, namely laser A and laser B. Two photodiodes detect the infrared light of the working wavelengths of laser A and laser B respectively.

3. The very early fire hazard warning system based on multispectral detection according to claim 2, characterized in that: The two photodiodes are respectively a silicon photodiode and an indium gallium arsenide diode; the silicon photodiode detects infrared light with a wavelength of 960nm emitted by the infrared light source, and the indium gallium arsenide diode detects infrared light with a wavelength of 1550nm emitted by the infrared light source.

4. The very early fire hazard warning system based on multispectral detection according to any one of claims 1 to 3, characterized in that: One of the detection light paths is based on the scattering principle. It determines the concentration of heat-damaged particles by detecting the intensity of scattered light caused by heat-damaged particles. The stronger the scattered light, the higher the concentration of heat-damaged particles. The other detection light path is based on the transmission principle. It determines the concentration of heat damage particles by detecting the intensity of transmitted light that propagates in a straight line through the heat damage particles. The stronger the transmitted light, the lower the concentration of heat damage particles.

5. The very early fire hazard warning system based on multispectral detection according to claim 1, characterized in that: An air valve for preventing gas backflow is installed at the air inlet of the air booster pump.

6. The very early fire hazard warning system based on multispectral detection according to claim 1, characterized in that: After the air pressure in the detection chamber reaches 0.1 MPa to 0.15 MPa, the photodiode measures the concentration of heat-damaged particles in the detection chamber.

7. The very early fire hazard warning system based on multispectral detection according to claim 1, characterized in that: An air pressure sensor is installed on the detection chamber to obtain the air pressure in the inner cavity of the detection chamber.

8. The very early fire hazard warning system based on multispectral detection according to claim 1, characterized in that: The photodiode is mounted on the detection chamber and extends into the detection chamber to measure the concentration of heat-damaged particles inside the detection chamber after the air pressure in the detection chamber reaches a set value.

9. The very early fire hazard warning system based on multispectral detection according to claim 1, characterized in that: The air inlet of the blower is connected to the air inlet of the box through a pipeline. The air inlet of the box is provided with an air volume detection module for detecting whether the air volume is normal.

10. The very early fire hazard warning system based on multispectral detection according to claim 1, characterized in that: It also includes an alarm to perform alarm processing when the concentration of heat-damaged particles reaches a set value and / or the rising speed of the concentration of heat-damaged particles exceeds a preset threshold.

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