A new type of red-violet ultraviolet flame detector field calibration system

Abstract

The application discloses a novel red-violet light flame detector field calibration system, and relates to the technical field of flame detection calibration.The system comprises a handheld device main body, a control panel, a control module, a light guide module and a battery assembly integrated in the handheld device main body; the control panel is electrically connected with the control module, and is used for inputting analog working condition parameters and feeding back running states; the control module is electrically connected with the light guide module and the battery assembly respectively, and is used for receiving the analog working condition parameters and generating excitation driving signals, collecting the response states of the detectors to be measured and outputting calibration results. Through the excitation current modulation of the multi-waveband light emitting unit, the application can simulate the real fire source with different combustion medium types, different transmission distances and different combustion areas, can quantitatively examine the detection capability boundary of the detector, and can break through the limitation that the traditional calibration can only qualitatively verify the on-off function, and can improve the reference value of the calibration results and the consistency of the calibration standards.

Description

Technical Field

[0001] This invention relates to the field of flame detection and verification technology, specifically to a novel on-site verification system for infrared and ultraviolet flame detectors. Background Technology

[0002] Infrared and ultraviolet flame detectors are a core component of fire early warning systems in flammable and explosive high-risk locations, and their stable and reliable detection performance is directly related to the fire safety of the premises. To ensure that the detectors can effectively identify fire signals after installation and operation, regular on-site functional verification is required to check the detectors' response capabilities and working status.

[0003] Currently, the mainstream on-site verification methods in the industry mainly include two types: open flame verification and detector self-testing function. When using on-site open flame verification, there are firstly obvious scene limitations. Open flame operations cannot be carried out in fire-prohibited areas such as gas stations and chemical plant areas, thus limiting the scope of application. Secondly, the combustion state of commonly used simple fire sources on-site is unstable, and the fire source conditions of different verifications are inconsistent. This can only qualitatively determine whether the detector has an alarm function, and cannot quantitatively assess the detector's ability to detect fire sources at different distances and with different burning areas. It is difficult to form a unified verification standard, and the open flame setup and operation procedures are cumbersome, resulting in low work efficiency.

[0004] When using the detector's built-in self-test function for testing, it can only complete the continuity test of the detector's internal circuitry and basic optical path. It cannot reproduce the multispectral radiation characteristics and dynamic flickering characteristics of real flames, nor can it simulate the differences in flame radiation intensity under different working conditions. It cannot effectively verify the actual operating effect of the detector's flame recognition algorithm, nor can it assess the detector's core performance indicators such as detection distance and anti-interference ability. The test results are difficult to reflect the detector's actual working ability in real fire scenarios.

[0005] In addition, some existing flame simulation testing equipment generally suffers from low spectral matching and significant differences between the emitted light morphology and real planar flames. Most of these devices can only simulate the characteristics of a single type of fire source and cannot equivalently reproduce the optical characteristics of flames under different fuels and operating conditions. At the same time, some devices are bulky and have many supporting components, making them inconvenient to move on-site and operate by a single person, and difficult to adapt to complex and diverse on-site testing needs. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a novel on-site verification system for infrared and ultraviolet flame detectors, comprising a handheld device body, and a control panel, control module, light guide module, and battery assembly integrated within the handheld device body. The control panel is electrically connected to the control module and is used to input simulated operating parameters and provide feedback on the operating status. The control module is electrically connected to the light guide module and the battery assembly, respectively, and is used to receive simulated operating condition parameters and generate excitation drive signals, while simultaneously acquiring the response status of the detector under test and outputting the verification results. The light guide module is located at the front end of the handheld device body and includes an infrared and / or ultraviolet emitting diode group, a tree-shaped light guide structure, a sapphire glass protective sheet, and a cover. The cover and the sapphire glass protective sheet enclose a sealed cavity, and the infrared and / or ultraviolet emitting diode group and the tree-shaped light guide structure are both located inside the sealed cavity. The incident end of the tree-shaped light guide structure is set to the light-emitting side of the red and / or ultraviolet emitting tube group, and the emitting end of the tree-shaped light guide structure is set to face the sapphire glass protective sheet, which is used to homogenize and mix multi-band radiation and output an equivalent flame radiation field outward. The battery assembly is used to provide DC power to the control panel, control module, and light guide module.

[0007] Preferably, the infrared and / or ultraviolet emitting diode group includes three infrared emitting units and one ultraviolet emitting unit, wherein the center wavelength of the first infrared emitting unit is 4.3 μm, the center wavelength of the second infrared emitting unit is 2.8 μm, the center wavelength of the third infrared emitting unit is 5 μm, and the wavelength range of the ultraviolet emitting unit is 0.15 μm to 0.4 μm.

[0008] Preferably, the tree-shaped light guide structure is made of sapphire glass, the side of the tree-shaped light guide structure is coated with a metallic gold reflective layer, and the emitting end of the tree-shaped light guide structure is processed with a matrix of square pyramid microstructures, which are used to diffusely reflect when radiation is conducted to the side of the square pyramid microstructures, so as to complete the uniform surface emission.

[0009] Preferably, the control panel includes an illuminated power supply component, a status indicator component, a start component, a simulated fire source type component, a simulated fire source distance component, and a simulated fire source area component; The simulated fire source type component is equipped with several selectable levels, which correspond to the simulation of fire sources and ultraviolet interference for different combustion media. The simulated fire source distance component is equipped with several selectable levels, each corresponding to a different equivalent fire source transmission distance. The simulated fire source area component is equipped with area settings for liquid fuel fire sources and settings for gaseous and solid fuel fire sources.

[0010] Preferably, the control module includes a parameter verification unit, an excitation calculation unit, a waveform generation unit, and a drive output unit; The parameter verification unit is used to perform combined legality verification on multiple sets of input simulated working condition parameters and output a valid target working condition configuration command. The excitation calculation unit is used to calculate the DC excitation base value of each transmitting unit according to the target operating condition configuration command, in conjunction with the built-in calibration feature parameter library. The waveform generation unit is used to superimpose AC jitter components on the DC excitation base value of each transmitting unit to generate a full-cycle excitation current waveform. The drive output unit is used to convert the full-cycle excitation current waveform into a corresponding drive signal and output it to each emitting unit of the light guide module.

[0011] Preferably, the calibration feature parameter library includes a fire source type spectral feature parameter library, an equivalent distance radiation attenuation parameter library, and a fire source area power correction parameter library; The excitation calculation unit sequentially obtains the DC excitation base value of each transmitting unit through spectral scaling, distance attenuation inverse correction, and area power amplitude correction.

[0012] Preferably, the AC jitter component generated by the waveform generation unit adopts a continuous frequency sweep operation mode, with an initial frequency of 4Hz, and the frequency is increased by 1Hz every 30 seconds until the frequency reaches 11Hz and then maintains a constant output. The excitation current waveform is based on a 20mA DC component and superimposed with the AC jitter component, and the amplitude of the AC component maintains a fixed ratio with the corresponding DC base value.

[0013] Preferably, the following specific settings are also included: When the simulated operating condition parameters are in ultraviolet interference mode, the waveform generation unit shuts down the excitation output of the three infrared emitting units and only outputs a square wave excitation signal with a frequency of 5Hz and a duty cycle of 50% to the ultraviolet emitting unit.

[0014] Preferably, the control module further includes a response acquisition unit and a verification and judgment unit; The response acquisition unit is used to continuously acquire the output response data of the infrared and ultraviolet flame detector under test throughout the entire cycle of the equivalent flame radiation field output. The verification and judgment unit is used to analyze the response data under target flame conditions and ultraviolet interference conditions respectively, determine the flame detection capability and anti-ultraviolet interference capability of the detector, and generate the on-site verification conclusion of the detector under test.

[0015] Beneficial effects This invention provides a novel on-site verification system for infrared and ultraviolet flame detectors, which has the following advantages: by modulating the excitation current of multi-band light-emitting units, it can equivalently simulate real fire sources with different types of combustion media, different transmission distances, and different combustion areas, and can quantitatively assess the detection capability boundary of the detector, breaking through the limitation of traditional verification that can only qualitatively verify the on / off state of functions, and improving the reference value of the verification results and the consistency with the verification standards. By combining multiple light sources to match the spectral radiation components of real flames, and using the diffuse reflection surface light emission effect of the tree-shaped light guide structure to restore the surface emission pattern of real flames, and combining frequency sweeping AC jitter modulation to reproduce the dynamic flicker characteristics of flames, the results closely resemble real flames from multiple dimensions such as spectral composition, spatial emission pattern, and dynamic flicker characteristics, effectively improving the accuracy and reliability of the verification results. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the process of the present invention.

[0017] Figure 2 This is a flowchart of the excitation drive signal generation process of the present invention.

[0018] Figure 3 This is a schematic diagram of the optical module composition of the present invention; Figure 4 This is a schematic diagram of the tree-shaped light guide structure of the present invention. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] This invention provides a novel on-site verification system for infrared and ultraviolet flame detectors, comprising a handheld device body, and a control panel, control module, light guide module, and battery assembly integrated within the handheld device body; The control panel is electrically connected to the control module and is used to input simulated operating parameters and provide feedback on the operating status. The control module is electrically connected to the light guide module and the battery assembly respectively. It is used to receive simulated operating parameters and generate excitation drive signals, while collecting the response status of the detector under test and outputting the verification results. The light guide module is located at the front end of the handheld device body and includes a red and / or ultraviolet emitting diode group, a tree-shaped light guide structure, a sapphire glass protective sheet and a cover. The cover and the sapphire glass protective sheet enclose a sealed cavity, and the red and / or ultraviolet emitting diode group and the tree-shaped light guide structure are both located inside the sealed cavity. The incident end of the tree-shaped light guide structure is set to the light-emitting side of the red and / or ultraviolet emitting tube group, and the emitting end of the tree-shaped light guide structure is set to face the sapphire glass protective sheet. It is used to homogenize and mix multi-band radiation and then output an equivalent flame radiation field. The battery assembly is used to provide DC power to the control panel, control module, and light guide module.

[0021] The infrared and / or ultraviolet emitting diode assembly includes three infrared emitting units and one ultraviolet emitting unit, wherein the center wavelength of the first infrared emitting unit is 4.3 μm, the center wavelength of the second infrared emitting unit is 2.8 μm, the center wavelength of the third infrared emitting unit is 5 μm, and the wavelength range of the ultraviolet emitting unit is 0.15 μm to 0.4 μm.

[0022] Please refer to the appendix. Figure 3 Schematic diagram of optical module composition and appendix Figure 4 The schematic diagram of the light guide structure shows four emitting units arranged on one side of the incident end of the tree-like light guide structure, each corresponding to an independent light guide branch entrance. The first infrared emitting unit, with a center wavelength of 4.3 μm, corresponds to the characteristic radiation peak of carbon dioxide gas generated during hydrocarbon fuel combustion, and is the core identification band for carbon combustion in the flame. The second infrared emitting unit, with a center wavelength of 2.8 μm, corresponds to the characteristic radiation peak of water vapor generated during combustion, and is a typical identification band for hydrogen combustion in the flame. The intensity ratio of the two bands differs depending on the carbon-hydrogen ratio of different fuels. The third infrared emitting unit, with a center wavelength of 5 μm, corresponds to the continuous background spectrum range of flame thermal radiation, serving as an intensity reference for quantifying the overall radiation intensity of the fire source, and is directly related to the simulation of the detection distance. The ultraviolet emitting units, with wavelengths from 0.15 μm to 0.4 μm, correspond to the near-ultraviolet and mid-ultraviolet radiation generated by the flame ionization reaction, serving as the detection basis for ultraviolet flame detectors and also used to simulate ultraviolet interference sources in the environment. The combination of these four bands can reproduce the multispectral characteristics of a real flame and distinguish the spectral differences of flames from different fuel types.

[0023] The control panel includes an illuminated power supply component, a status indicator component, a startup component, a simulated fire source type component, a simulated fire source distance component, and a simulated fire source area component; The simulated fire source type component has several selectable settings, corresponding to fire source simulation and ultraviolet interference simulation for different combustion media; The simulated fire source distance component has several selectable settings, each corresponding to a different equivalent fire source transmission distance; The simulated fire source area component is set with area settings for liquid fuel fire sources and settings for gaseous and solid fuel fire sources.

[0024] The control module includes a parameter verification unit, an excitation calculation unit, a waveform generation unit, and a drive output unit; The parameter verification unit is used to perform combined legality verification on multiple sets of input simulated working condition parameters and output valid target working condition configuration instructions. The control module, as the core computing unit, is integrated inside the main body of the device, receiving input signals from the control panel and output control from the light guide module. The combination validity verification refers to the logical matching and verification of three parameters selected by the user: fire source type, equivalent distance, and fire source area. Specifically, the process is as follows: First, the fuel category to which the fire source type belongs is identified. If it is a gaseous or solid fuel category, the area setting is checked to see if it matches the corresponding dedicated setting. If a liquid fuel area setting is mistakenly selected, it automatically adapts to the corresponding dedicated setting. If an ultraviolet interference condition is selected, the calculation channels for the equivalent distance and fire source area parameters are directly blocked, retaining only the configuration logic for the ultraviolet band to prevent invalid parameters from participating in subsequent calculations. After verification, a logically consistent and unique target condition configuration instruction is generated to ensure that the subsequently calculated condition parameters conform to the optical laws of actual combustion. The excitation calculation unit is used to calculate the DC excitation base value of each transmitting unit according to the target operating condition configuration command, based on the built-in calibration feature parameter library. This application first retrieves the spectral ratio parameter corresponding to the fire source type of the target operating condition to determine the relative intensity ratio of radiation in each band; then retrieves the radiation attenuation parameter corresponding to the equivalent distance, and adjusts the initial intensity of each band in reverse gain according to the attenuation law of light transmission in the atmosphere; finally, retrieves the power parameter corresponding to the fire source area to adjust the total intensity of each band synchronously; after three layers of continuous calculation, the DC current reference value corresponding to each transmitting unit is obtained. This value corresponds to the luminous intensity of the transmitting unit under constant output state and is the reference for subsequent superposition of scintillation components. The waveform generation unit is used to superimpose AC jitter components onto the DC excitation base value of each transmitting unit to generate a full-cycle excitation current waveform. The AC jitter component is a periodic intensity fluctuation signal that simulates the flickering characteristics of a real flame. The generation process is as follows: based on the DC excitation base value, the fluctuation amplitude is extracted according to a fixed ratio to generate a fluctuation signal that changes periodically with time. This fluctuation signal is superimposed on the DC base value so that the final output excitation current is always in the positive operating range, and the luminous intensity exhibits an alternating flickering state with increasing intensity over time, rather than a constant output. The full-cycle excitation current waveform covers the complete time interval from the start to the end of the frequency sweep, including the complete frequency change process. The drive output unit is used to convert the full-cycle excitation current waveform into a corresponding drive signal and output it to each emitting unit of the light guide module. It converts the digital waveform signal generated by the control module into a continuous analog current signal, and then amplifies and conditions the current through the power drive circuit to ensure that the stability and accuracy of the output current match the working requirements of the emitting unit. Finally, it delivers the excitation current that meets the set waveform to the corresponding emitting unit to drive it to emit light radiation with corresponding intensity and flicker characteristics.

[0025] The calibration characteristic parameter library includes a fire source type spectral characteristic parameter library, an equivalent distance radiation attenuation parameter library, and a fire source area power correction parameter library; Furthermore, the spectral characteristic parameter library for fire source types consists of fixed data obtained by statistically analyzing the radiation intensity of real flames of different fuels in each band, with different proportional parameters corresponding to different fuels; the equivalent distance radiation attenuation parameter library is based on the atmospheric radiation transmission law, combined with the absorption and scattering characteristics of different bands in the air, statistically analyzing the corresponding relationship of light intensity attenuation of each band at different transmission distances, with greater light intensity attenuation at greater distances; the fire source area power correction parameter library is based on the correspondence between combustion area and total radiative flux, statistically analyzing the total radiative power correction coefficient corresponding to different combustion areas, with higher total radiative power for larger combustion areas. The excitation calculation unit sequentially obtains the DC excitation base value of each transmitting unit through spectral scaling, distance attenuation inverse correction, and area power amplitude correction. In this step, spectral scaling refers to determining the relative intensity ratio of each band according to the type of fire source; distance attenuation inverse correction refers to increasing the output intensity of the transmitting end in reverse to offset the light intensity advantage at close range in order to simulate the weak light effect at a distance, so that the light intensity of the detector receiving end is equivalent to the real fire source at the target distance; area power amplitude correction refers to adjusting the total radiation power according to the target burning area so that the radiant output of the equivalent radiation surface matches the real flame of the target area.

[0026] The AC jitter component generated by the waveform generation unit adopts a continuous frequency sweep operation mode, with an initial frequency of 4Hz. The frequency is increased by 1Hz every 30 seconds until it reaches 11Hz, after which a constant output is maintained. This is because 4Hz to 11Hz covers the flame recognition frequency range of mainstream detectors on the market. By gradually sweeping the frequency, the detector's response capability at different flicker frequencies can be comprehensively tested. The setting of 1Hz increment every 30 seconds ensures that there is sufficient dwell time for the detector to respond at each frequency point, and also ensures that the overall calibration time is within a reasonable range. The 20mA DC component is used as the reference because this current value is in the typical positive operating range of the infrared and ultraviolet light-emitting diode, which can ensure that the light-emitting diode is stably in the emitting state. The AC component amplitude is kept in a fixed ratio with the DC base value, which can ensure that the relative depth of flicker is consistent under different intensity levels, which conforms to the flicker characteristics of real flames, while avoiding the light-emitting diode from being cut off and extinguished due to excessively low current. The excitation current waveform is based on a 20mA DC component with an AC jitter component superimposed on it, and the amplitude of the AC component maintains a fixed ratio with the corresponding DC base value.

[0027] It also includes the following specific settings: When the simulated operating condition parameters are in ultraviolet interference mode, the waveform generation unit shuts down the excitation output of the three infrared emitting units and only outputs a square wave excitation signal with a frequency of 5Hz and a duty cycle of 50% to the ultraviolet emitting unit. The square wave signal with a frequency of 5Hz and a duty cycle of 50% simulates the flicker characteristics of a typical ultraviolet interference source and is used to verify the detector's composite identification logic—that is, the alarm is only triggered when both infrared and ultraviolet flame characteristics are matched simultaneously, and there should be no false alarm when only ultraviolet radiation is present. This completes the verification of the detector's anti-interference performance.

[0028] The control module also includes a response acquisition unit and a verification and judgment unit; The response acquisition unit is used to continuously acquire the output response data of the infrared and ultraviolet flame detector under test throughout the entire cycle of the equivalent flame radiation field output. The verification and judgment unit is used to analyze the response data under target flame conditions and ultraviolet interference conditions respectively, to determine the flame detection capability and anti-ultraviolet interference capability of the detector, and to generate the on-site verification conclusion of the detector under test.

Claims

1. A novel on-site calibration system for infrared and ultraviolet flame detectors, characterized in that: It includes a handheld device body, and a control panel, control module, light guide module and battery assembly integrated within the handheld device body; The control panel is electrically connected to the control module and is used to input simulated operating parameters and provide feedback on the operating status. The control module is electrically connected to the light guide module and the battery assembly, respectively, and is used to receive simulated operating condition parameters and generate excitation drive signals, while simultaneously acquiring the response status of the detector under test and outputting the verification results. The light guide module is located at the front end of the handheld device body and includes an infrared and / or ultraviolet emitting diode group, a tree-shaped light guide structure, a sapphire glass protective sheet, and a cover. The cover and the sapphire glass protective sheet enclose a sealed cavity, and the infrared and / or ultraviolet emitting diode group and the tree-shaped light guide structure are both located inside the sealed cavity. The incident end of the tree-shaped light guide structure is set to the light-emitting side of the red and / or ultraviolet emitting tube group, and the emitting end of the tree-shaped light guide structure is set to face the sapphire glass protective sheet, which is used to homogenize and mix multi-band radiation and output an equivalent flame radiation field outward. The battery assembly is used to provide DC power to the control panel, control module, and light guide module.

2. The novel on-site calibration system for an infrared-ultraviolet flame detector according to claim 1, characterized in that: The infrared and / or ultraviolet emitting diode group includes three infrared emitting units and one ultraviolet emitting unit, wherein the center wavelength of the first infrared emitting unit is 4.3 μm, the center wavelength of the second infrared emitting unit is 2.8 μm, the center wavelength of the third infrared emitting unit is 5 μm, and the wavelength range of the ultraviolet emitting unit is 0.15 μm to 0.4 μm.

3. The novel on-site calibration system for an infrared-ultraviolet flame detector according to claim 1, characterized in that: The tree-shaped light guide structure is made of sapphire glass. The sides of the tree-shaped light guide structure are coated with a metallic gold reflective layer. The emitting end of the tree-shaped light guide structure is processed with a matrix of square pyramid microstructures, which are used to diffusely reflect radiation when it is radiated to the sides of the square pyramid microstructures, thus achieving uniform surface emission.

4. The novel on-site calibration system for an infrared-ultraviolet flame detector according to claim 1, characterized in that: The control panel includes an illuminated power supply component, a status indicator component, a start component, a simulated fire source type component, a simulated fire source distance component, and a simulated fire source area component; The simulated fire source type component is equipped with several selectable levels, which correspond to the simulation of fire sources and ultraviolet interference for different combustion media. The simulated fire source distance component is equipped with several selectable levels, each corresponding to a different equivalent fire source transmission distance. The simulated fire source area component is equipped with area settings for liquid fuel fire sources and settings for gaseous and solid fuel fire sources.

5. A novel on-site calibration system for an infrared-ultraviolet flame detector according to claim 1, characterized in that: The control module includes a parameter verification unit, an excitation calculation unit, a waveform generation unit, and a drive output unit; The parameter verification unit is used to perform combined legality verification on multiple sets of input simulated working condition parameters and output a valid target working condition configuration command. The excitation calculation unit is used to calculate the DC excitation base value of each transmitting unit according to the target operating condition configuration command, in conjunction with the built-in calibration feature parameter library. The waveform generation unit is used to superimpose AC jitter components on the DC excitation base value of each transmitting unit to generate a full-cycle excitation current waveform. The drive output unit is used to convert the full-cycle excitation current waveform into a corresponding drive signal and output it to each emitting unit of the light guide module.

6. A novel on-site calibration system for an infrared-ultraviolet flame detector according to claim 5, characterized in that: The calibration feature parameter library includes a fire source type spectral feature parameter library, an equivalent distance radiation attenuation parameter library, and a fire source area power correction parameter library; The excitation calculation unit sequentially obtains the DC excitation base value of each transmitting unit through spectral scaling, distance attenuation inverse correction, and area power amplitude correction.

7. A novel on-site calibration system for an infrared-ultraviolet flame detector according to claim 5, characterized in that: The AC jitter component generated by the waveform generation unit adopts a continuous frequency sweep operation mode, with an initial frequency of 4Hz. The frequency is increased by 1Hz every 30 seconds until the frequency reaches 11Hz and then maintains a constant output. The excitation current waveform is based on a 20mA DC component with an AC jitter component superimposed on it, and the amplitude of the AC component maintains a fixed ratio with the corresponding DC base value.

8. A novel on-site calibration system for an infrared and ultraviolet flame detector according to claim 5, characterized in that: It also includes the following specific settings: When the simulated operating condition parameters are in ultraviolet interference mode, the waveform generation unit shuts down the excitation output of the three infrared emitting units and only outputs a square wave excitation signal with a frequency of 5Hz and a duty cycle of 50% to the ultraviolet emitting unit.

9. A novel on-site calibration system for an infrared-ultraviolet flame detector according to claim 1, characterized in that: The control module also includes a response acquisition unit and a verification and judgment unit; The response acquisition unit is used to continuously acquire the output response data of the infrared and ultraviolet flame detector under test throughout the entire cycle of the equivalent flame radiation field output. The verification and judgment unit is used to analyze the response data under target flame conditions and ultraviolet interference conditions respectively, determine the flame detection capability and anti-ultraviolet interference capability of the detector, and generate the on-site verification conclusion of the detector under test.

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