Flame detector

Abstract

To provide a flame detector capable of highly precisely detecting occurrence of flame by suppressing erroneous detection.SOLUTION: A flame detector includes a flame occurrence determination processing unit that performs determination processing of determining presence or absence of flame according to a sensitivity level. The flame occurrence determination processing unit has a discrimination and notification capability of discriminating a condition where a flame signal should be outputted based on a result of determination processing on a second stage from a condition where an alarm signal should be outputted, and notifying the discriminated condition. Namely, the flame occurrence determination processing unit can change settings between an initial sensitivity level and a low sensitivity level. When performing determination processing according to the initial sensitivity level as a first stage, and determining as a result that flame has occurred, the flame occurrence determination processing unit changes the levels from the initial sensitivity level to the low sensitivity level. When performing determination processing according to the low sensitivity level as a second stage and determining as a result similarly to the first stage that flame has occurred, the flame occurrence determination processing unit outputs a flame signal. When determining dissimilarly to the first stage that flame has not occurred, the flame occurrence determination processing unit outputs an alarm signal.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a flame detection device capable of performing discrimination processing for the presence or absence of flame generation at multiple sensitivity levels.

Background Art

[0002] As disaster prevention equipment for detecting and notifying fires, there are various types of flame detection devices. Specific types of flame detection devices include an infrared spot-type sensor and an ultraviolet spot-type sensor.

[0003] In addition, there is a flame detection device capable of eliminating false alarm sources and removing noise to detect flames with high accuracy (see, for example, Patent Document 1). The flame detection device according to Patent Document 1 detects flames with high accuracy based on the detection results of light of different wavelengths.

[0004] Generally used heat sensors and smoke sensors detect heat or smoke only when it reaches the installed location. For this reason, when heat sensors and smoke sensors are installed in places where outside air constantly circulates or high ceilings, etc., it is assumed that it takes time to detect a fire, such as the heat and smoke being diluted and the time it takes for the heat and smoke to reach the sensor.

[0005] On the other hand, the flame detection device according to Patent Document 1 detects a fire by capturing the radiant energy (CO2 resonance radiation) from the flame emitted when an object burns. As a result, the flame detection device according to Patent Document 1 directly receives the radiant energy emitted by the flame to detect a fire, and can detect a fire more reliably without a time delay for a fire accompanied by a flame, and is a particularly effective flame detection device for an atrium having a high ceiling.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] Depending on the installation environment, there are various false alarm sources in the fire monitoring area. For example, in a factory, if the area where welding work is carried out is included, there is a risk of fire due to the welding work. Therefore, while it is desirable to detect flames with high precision, it is important to suppress the misdetection of the flames of the welding work itself as a fire.

[0008] The present disclosure has been made to solve the above problems, and an object thereof is to obtain a flame detection device capable of detecting the occurrence of a flame with high precision while suppressing misdetection.

Means for Solving the Problems

[0009] The flame detection device according to the present disclosure is a flame detection device including a flame occurrence determination processing unit that executes a determination process for the presence or absence of a flame according to a sensitivity level set for determining that a flame has occurred in a fire monitoring area. The flame occurrence determination processing unit can switch the setting between an initially set initial sensitivity level and a low sensitivity level having a lower sensitivity for determining that a flame has occurred than the initial sensitivity level. When it is determined that a flame has occurred by executing the determination process according to the initial sensitivity level as the first stage, the sensitivity level is switched from the initial sensitivity level to the low sensitivity level. When it is determined that a flame has occurred in the same manner as in the first stage by executing the determination process according to the low sensitivity level as the second stage, a fire signal is output. When it is determined that no flame has occurred, different from the first stage, by executing the determination process according to the low sensitivity level as the second stage, a warning signal is output. It has an identification notification function for identifying and notifying a state in which a fire signal should be output and a state in which a warning signal should be output according to the two-stage determination processing results by the first-stage determination processing using the initial sensitivity level and the second-stage determination processing using the low sensitivity level.

Effects of the Invention

[0010] According to the present disclosure, a flame detection device capable of detecting the occurrence of a flame with high accuracy while suppressing false detection can be obtained.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0012] Hereinafter, preferred embodiments of the flame detection device of the present disclosure will be described with reference to the drawings. The flame detection device according to the present disclosure performs two-stage discrimination processing using an initially set initial sensitivity level and a low sensitivity level with a lower sensitivity for determining that a flame has occurred than the initial sensitivity level, and has an identification notification function capable of notifying an output signal according to the two-stage discrimination processing result as a technical feature.

[0013] Embodiment 1. FIG. 1 is a functional block diagram showing the configuration of the flame detection device according to Embodiment 1 of the present disclosure. The flame detection device 100 according to Embodiment 1 includes a flame occurrence discrimination processing unit 110 and a sensitivity level storage unit 120.

[0014] The flame occurrence determination processing unit 110 executes the determination processing of whether a flame has occurred according to the sensitivity level set to determine the occurrence of a flame in the fire monitoring area. The flame occurrence determination processing unit 110 according to the present disclosure is characterized by having an identification notification function 111 as a technical feature.

[0015] The sensitivity level storage unit 120 stores in advance two sensitivity levels, namely, the initially set initial sensitivity level and a low sensitivity level at which the sensitivity for determining the occurrence of a flame is lower than the initial sensitivity level, as the sensitivity levels used for the determination processing of whether a flame has occurred.

[0016] Next, the identification notification function 111, which is a technical feature of the flame detection device 100 according to the present disclosure, will be specifically described. The flame occurrence determination processing unit 110 can switch the setting of the sensitivity level between the initial sensitivity level and the low sensitivity level, and reads out either the initial sensitivity level or the low sensitivity level from the sensitivity level storage unit 120 as needed.

[0017] The flame occurrence determination processing unit 110 will execute the identification notification function 111 according to the following procedure. <Step 1> First-stage determination processing As the first stage, the flame occurrence determination processing unit 110 reads out the initial sensitivity level from the sensitivity level storage unit 120 and executes the determination processing according to the initial sensitivity level. As a result, if it is determined that no flame has occurred, the flame occurrence determination processing unit 110 determines that the fire monitoring area is in a normal state, repeats the first-stage determination processing, and continues the fire monitoring.

[0018] On the other hand, if it is determined that a flame has occurred as a result of executing the determination processing according to the initial sensitivity level, proceed to Step 2.

[0019] <Step 2> Second-stage determination processing As the second stage, the flame occurrence determination processing unit 110 reads out the low sensitivity level from the sensitivity level storage unit 120 and executes the determination processing according to the low sensitivity level. As a result, similar to the first stage, when it is determined that a flame has occurred even when using the low sensitivity level, the flame occurrence determination processing unit 110 outputs a fire signal as a notification signal.

[0020] On the other hand, as a result of executing the determination processing according to the low sensitivity level, different from the first stage, when it is determined that no flame has occurred when using the low sensitivity level, the flame occurrence determination processing unit 110 outputs a warning signal as a notification signal.

[0021] As a result, not only can it simply be determined whether a flame has occurred using the low sensitivity level, but also a state where the occurrence of a flame is not detected at the low sensitivity level but can be detected at the high sensitivity level can be identified by outputting a warning signal.

[0022] In other words, the flame occurrence determination processing unit 110 has an identification notification function of identifying and notifying a state in which a fire signal should be output and a state in which a warning signal should be output according to the two-stage determination processing results of the first-stage determination processing using the initial sensitivity level and the second-stage determination processing using the low sensitivity level.

[0023] As an example, a case where the flame detection device 100 equipped with the identification notification function 111 is applied when a section where welding work is carried out is partially included in the fire monitoring area will be described. FIG. 2 is an explanatory diagram showing a specific example of a fire monitoring area to which the flame detection device according to Embodiment 1 of the present disclosure is applied.

[0024] In FIG. 2, the fire monitoring area is divided into 12 monitoring sections A11 to A16, A21 to A26. Here, each of the 12 monitoring sections is divided into a high-sensitivity area that executes the determination processing of the presence or absence of a flame with high sensitivity and a low-sensitivity area that executes the determination processing of the presence or absence of a flame with low sensitivity in order to suppress false detections.

[0025] Specifically, the three sections of monitoring sections A15, A16, and A22 are the sections where welding work is carried out, and they correspond to low-sensitivity areas that perform discrimination processing on the presence or absence of flames with low sensitivity in order to suppress false detections. The hatched monitoring sections in Fig. 2 correspond to the sections where welding work is carried out, that is, the low-sensitivity areas.

[0026] On the other hand, the nine sections other than the three sections of monitoring sections A15, A16, and A22 are the sections where welding work is not carried out, and since there is no false detection of welding work, they correspond to high-sensitivity areas that perform discrimination processing on the presence or absence of flames with high sensitivity.

[0027] In the fire monitoring area shown in Fig. 2, by installing the flame detection device 100 equipped with the identification notification function 111 for the monitoring sections A15, A16, and A22 where welding work is carried out, the following effects 1 and 2 can be achieved.

[0028] Effect 1: It is possible to prevent a fire signal from being notified based only on the discrimination processing result at the initial sensitivity level, and prevent the flame caused by welding work from being misjudged as a fire immediately.

[0029] Effect 2: Even when it is determined that no flame is generated at the low-sensitivity level, if it can be determined that a flame is generated at the high-sensitivity level, a warning signal can be notified, and it is possible to prevent a situation where no notification is made based only on the discrimination processing result at the low-sensitivity level.

[0030] In this way, by performing the two-stage discrimination processing by the identification notification function 111, it is possible to prevent a fire signal from being output when the light generated during the welding work can be detected at the high-sensitivity level but not at the low-sensitivity level, and it can be identified by outputting a warning signal.

[0031] As described above, according to Embodiment 1, a flame detection device having an identification notification function capable of performing two-stage discrimination processing based on an initial sensitivity level and a low sensitivity level and notifying an output signal according to the two-stage discrimination processing result is realized. As a result, even when the sensitivity level is lowered to suppress false detection, it is possible to notify, as a warning signal, the state in which the occurrence of a flame could be detected only at the high sensitivity level, and it is possible to prompt attention.

[0032] Therefore, for example, in a fire monitoring area that partially includes a monitoring section where welding work is performed, by installing a flame detection device having an identification notification function for the monitoring section where welding work is performed, it is possible to suppress false detection due to the welding work itself and quickly notify a state in which there is a risk of a fire occurring subsequently due to the welding work.

[0033] Note that the setting of whether to use the identification notification function can be considered to be either fixedly performed or dynamically performed according to the fire monitoring situation. Therefore, the specific configuration regarding the former will be described in Embodiment 2, and the specific configuration regarding the latter will be described in Embodiments 3 and 4.

[0034] Embodiment 2. FIG. 3 is a functional block diagram showing the configuration of the flame detection device according to Embodiment 2 of the present disclosure. The flame detection device 100 according to Embodiment 2 further includes a sensitivity area setting unit 130 in addition to the flame occurrence discrimination processing unit 110 and the sensitivity level storage unit 120 as compared with the configuration of the flame detection device 100 according to the previous Embodiment 1 shown in FIG. 1. Therefore, the following description will focus on the function of the newly added sensitivity area setting unit 130.

[0035] The sensitivity area setting unit 130 can switch between a high sensitivity setting indicating a state of being installed in a high sensitivity area and a low sensitivity setting indicating a state of being installed in a low sensitivity area according to a sensitivity area setting input.

[0036] For example, the sensitivity area setting unit 130 can adopt a configuration with a switch that can be switched manually or a configuration with a receiving function that can be switched by receiving an electrical command signal, and can set whether the flame detection device 100 is installed in a high-sensitivity area or a low-sensitivity area.

[0037] When the sensitivity area setting unit 130 is configured with the former switch, the manual operation input corresponds to the sensitivity area setting input. On the other hand, when the sensitivity area setting unit 130 is configured with the latter receiving function, the electrical command signal given from the outside corresponds to the sensitivity area setting input.

[0038] Taking the previous Figure 2 as an example to explain the setting method of the sensitivity area setting unit 130, for the monitoring sections A15, A16, and A22 where welding operations are carried out, after installing the flame detection device 100 equipped with the identification notification function 111, the setting state by the sensitivity area setting unit 130 is set to low sensitivity.

[0039] As a result, the flame occurrence determination processing unit 110 can execute the identification notification function 111 in the monitoring sections A15, A16, and A22 where welding operations are carried out by determining that it is a monitoring section corresponding to the low-sensitivity area from the setting state by the sensitivity area setting unit 130.

[0040] In addition, when the setting state by the sensitivity area setting unit 130 is high sensitivity, the flame occurrence determination processing unit 110 does not execute the identification notification function, but determines whether a flame has occurred by executing a one-stage determination process according to the initial sensitivity level.

[0041] As described above, according to the second embodiment, it is possible to switch between a high-sensitivity setting mode in which a one-stage determination process is performed without using the identification notification function and a low-sensitivity setting mode in which a two-stage determination process is performed using the identification notification function by the sensitivity area setting unit. Therefore, by setting to an appropriate mode according to the monitoring section, it is possible to fixedly set whether to execute the identification notification function without change.

[0042] Embodiment 3 FIG. 4 is a functional block diagram showing the configuration of the flame detection device according to Embodiment 3 of the present disclosure. The flame detection device 100 according to Embodiment 3 further includes a receiving unit 140 in addition to the flame generation determination processing unit 110 and the sensitivity level storage unit 120 as compared with the configuration of the flame detection device 100 according to the previous Embodiment 1 shown in FIG. 1. Therefore, the following description will focus on the functions of the newly added receiving unit 140.

[0043] The receiving unit 140 has a function of receiving an identification notification flag from the outside that defines whether or not to execute the identification notification function 111. As an example, the identification notification flag is set to 1 when the identification notification function 111 is to be executed, and set to 0 when the identification notification function 111 is not to be executed.

[0044] Therefore, when the identification notification flag received by the receiving unit 140 is set to 1, the flame generation determination processing unit 110 can execute the identification notification function 111. On the other hand, when the identification notification flag received by the receiving unit 140 is set to 0, the flame generation determination processing unit 110 does not execute the identification notification function 111 and only executes a one-step determination process according to the initial sensitivity level to determine whether a high-sensitivity flame has occurred.

[0045] Taking the previous FIG. 2 as an example, the usage method of the receiving unit 140 will be described. In the monitoring sections A15, A16, and A22 where welding work is being carried out, during the welding work, when the receiving unit 140 receives the identification notification flag set to 1, the flame generation determination processing unit 110 can execute the identification notification function 111 in the monitoring sections A15, A16, and A22 where the welding work is being carried out.

[0046] Also, in the monitoring sections A15, A16, and A22, when the welding work is not being carried out, when the receiving unit 140 receives the identification notification flag set to 0, the flame generation determination processing unit 110 does not execute the identification notification function 111 in the monitoring sections A15, A16, and A22 where the welding work is being carried out, and only executes a one-step determination process according to the initial sensitivity level to determine whether a high-sensitivity flame has occurred.

[0047] In this way, even in the same monitoring section, it is possible to switch whether to execute the identification notification function 111 by the identification notification flag according to the situation. For example, also in the area where welding work is carried out, by setting the identification notification flag to 0 during the period when welding work is not carried out including at night, it is possible to quickly notify with high precision the fire detection including the state where there is a risk of fire occurring subsequently due to the welding work.

[0048] As described above, according to the third embodiment, according to the setting state of the recognition notification flag received by the receiving unit, it is possible to switch between a high-sensitivity setting mode in which a one-stage discrimination process is performed without using the identification notification function and a low-sensitivity setting mode in which a two-stage discrimination process is performed using the identification notification function. Therefore, by dynamically setting an appropriate mode according to the situation of the monitoring section, it is possible to easily switch and set whether to execute the identification notification function.

[0049] Embodiment 4. FIG. 5 is a functional block diagram showing the configuration of the flame detection device according to the fourth embodiment of the present disclosure. The flame detection device 100 according to the fourth embodiment further includes an image processing unit 150 in addition to the flame occurrence discrimination processing unit 110 and the sensitivity level storage unit 120 as compared with the configuration of the flame detection device 100 according to the first embodiment shown in FIG. 1. Therefore, the following description will focus on the functions of the newly added image processing unit 150.

[0050] In the fourth embodiment, as a specific example, a case will be described in which the low-sensitivity area corresponds to the area where welding work is carried out, and in this low-sensitivity area, the setting of whether to use the identification notification function 111 is dynamically performed according to the implementation status of the welding work.

[0051] A camera 200 for imaging the location where welding work is carried out is installed in the low-sensitivity area. The image processing unit 150 has a function of acquiring the captured image captured by the camera 200 and performing image processing on the captured image to determine whether welding work is being carried out in the low-sensitivity area.

[0052] When it is determined by the image processing unit 150 that welding work is in progress, the flame occurrence determination processing unit 110 executes an identification notification function in a low-sensitivity area in order to suppress misdetection of the welding work itself as a fire.

[0053] On the other hand, when it is determined by the image processing unit 150 that welding work is not in progress, the flame occurrence determination processing unit 110 does not execute the identification notification function in the low-sensitivity area and determines whether a flame has occurred with high sensitivity by executing only a one-stage determination process according to the initial sensitivity level.

[0054] The usage method of the image processing unit 150 will be described using FIG. 2 above as an example. Each of the flame detectors 100 installed in the monitoring sections A15, A16, and A22 where welding work is performed has an image processing unit 150, and by performing image processing on the captured image captured by the camera 200, it is possible to determine whether welding work is in progress.

[0055] On the other hand, based on the image processing result, the flame occurrence determination processing unit 110 executes the identification notification function 111 only when welding work is in progress in the monitoring sections A15, A16, and A22. That is, in a low-sensitivity area involving welding work, when welding work is in progress, the flame occurrence determination processing unit 110 can suppress misdetection by performing a two-stage determination process including a first-stage determination process using the initial sensitivity level and a second-stage determination process using the low-sensitivity level.

[0056] Further, even in a low-sensitivity area involving welding work, when welding work is not being performed, the flame occurrence determination processing unit 110 can determine whether a flame has occurred with high sensitivity by executing only a one-stage determination process according to the initial sensitivity level without executing the identification notification function 111.

[0057] In this way, even in the same monitoring section, it is possible to switch whether to execute the identification notification function 111 according to the image processing result for determining the execution status of the welding operation in real time.

[0058] As a result, while suppressing false detection during welding operations, by specifying in real time as an image processing result the period when welding operations are not being carried out, including at night, it is possible to quickly notify with high precision of fire detection including situations where there is a risk of a fire occurring subsequently due to welding operations.

[0059] As described above, according to Embodiment 4, it is possible to switch between a high-sensitivity setting mode that performs a one-stage discrimination process without using the identification notification function and a low-sensitivity setting mode that performs a two-stage discrimination process using the identification notification function according to the image processing result. Therefore, by dynamically setting an appropriate mode according to the situation of the monitoring section, it is possible to easily switch the setting of whether to execute the identification notification function.

[0060] In the above-described Embodiments 1 to 4, the case of dividing into two sensitivity levels, a high-sensitivity area and a low-sensitivity area, has been described. However, the flame detection device according to the present disclosure is not limited to such a case. It is also possible to subdivide the low-sensitivity level into a plurality of two or more sensitivity levels, divide into three or more sensitivity levels, and assign different output signals according to the multi-stage sensitivity levels.

[0061] Also, as the flame detection device according to the present disclosure, an infrared three-wavelength type flame detection device as disclosed in Patent Document 1 can also be applied. In this case, it can be expected that flames can be detected with high precision even by a discrimination process with a reduced sensitivity level.

[0062] In addition, it is also conceivable to install flame detection devices with different performances in the high-sensitivity area and the low-sensitivity area. As an example, for the high-sensitivity area, it is conceivable to apply a conventional single-wavelength flame detection device that does not have the discrimination notification function 111, and for the low-sensitivity area, to apply an infrared three-wavelength flame detection device equipped with the discrimination notification function 111. By adopting such a configuration, the cost of the entire system can be suppressed.

[0063] Furthermore, for example, when welding work is carried out in the low-sensitivity area, in order to suppress false detection, a fire signal is output based on the discrimination processing result with the set sensitivity lowered by utilizing the discrimination notification function 111. However, by using an infrared three-wavelength flame detection device that can perform flame detection with high precision, deterioration of the detection accuracy can be suppressed.

[0064] Also, in the above-described Embodiments 1 to 4, when the occurrence of a flame could be detected at a high sensitivity level but not at a low sensitivity level, a warning signal was immediately output. However, the flame detection device according to the present disclosure is not limited to such a case.

[0065] For example, it is also possible to adopt a configuration in which the cumulative number of times the warning signal is output or the cumulative time in the state where the warning signal is output is set, and the warning signal is output when the cumulative number or the cumulative time exceeds the allowable threshold value. By adopting such a configuration, the frequency of outputting the warning signal can be suppressed.

Explanation of Reference Numerals

[0066] 100 Flame detection device, 110 Flame occurrence discrimination processing unit, 111 Discrimination notification function, 120 Sensitivity level storage unit, 130 Sensitivity area setting unit, 140 Receiver, 150 Image processing unit, 200 Camera.

Claims

1. A flame detection device comprising a flame occurrence determination processing unit that executes determination processing for the presence or absence of a flame according to a sensitivity level set to determine the occurrence of a flame in a fire monitoring area, wherein the flame occurrence determination processing unit, is capable of switching the setting between an initially set initial sensitivity level and a low sensitivity level with a lower sensitivity for determining the occurrence of a flame than the initial sensitivity level, when it is determined that a flame has occurred by executing the determination processing according to the initial sensitivity level in the first stage, switches from the initial sensitivity level to the low sensitivity level, when it is determined that a flame has occurred in the same manner as in the first stage by executing the determination processing according to the low sensitivity level in the second stage, outputs a fire signal, when it is determined that no flame has occurred, different from the first stage, by executing the determination processing according to the low sensitivity level in the second stage, outputs a warning signal, has an identification notification function of identifying and notifying a state in which the fire signal should be output and a state in which the warning signal should be output according to the two-stage determination processing results of the first-stage determination processing using the initial sensitivity level and the second-stage determination processing using the low sensitivity level flame detection device.

2. In the fire monitoring area having a monitoring section divided into a high-sensitivity area that executes high-sensitivity determination processing for the presence or absence of a flame and a low-sensitivity area that executes low-sensitivity determination processing for the presence or absence of a flame to suppress false detection, installed for each monitoring section, further comprising a sensitivity area setting unit capable of setting whether it is installed in the high-sensitivity area or the low-sensitivity area, wherein the flame occurrence determination processing unit, when it is determined from the setting state by the sensitivity area setting unit that it is installed in a monitoring section corresponding to the low-sensitivity area, executes the identification notification function, when it is determined from the setting state by the sensitivity area setting unit that it is installed in a monitoring section corresponding to the high-sensitivity area, does not execute the identification notification function and determines whether a flame has occurred by executing the determination processing according to the initial sensitivity level The flame detection device according to claim 1.

3. further comprising a receiving unit that receives from the outside an identification notification flag that defines whether to execute the identification notification function, wherein the flame occurrence determination processing unit, When the identification notification flag received by the receiving unit is set to 1, the identification notification function is executed. When the identification notification flag received by the receiving unit is set to 0, the identification notification function is not executed, and it is determined whether a fire has occurred by executing the discrimination process according to the initial sensitivity level. The flame detection device according to claim 1.

4. The low-sensitivity area is an area where welding work is performed. It further includes an image processing unit that acquires a captured image from a camera that captures the low-sensitivity area, and performs image processing on the captured image to determine whether the welding work is being performed in the low-sensitivity area. The fire occurrence determination processing unit When it is determined by the image processing unit that the welding work is being performed, the identification notification function is executed in the low-sensitivity area. When it is determined by the image processing unit that the welding work is not being performed, the identification notification function is not executed in the low-sensitivity area, and it is determined whether a fire has occurred by executing the discrimination process according to the initial sensitivity level. The flame detection device according to claim 2.

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