JP2017166737A - Fire inside exhaust duct detection system and alarm device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fire inside an exhaust duct detection system which can detect a fire at an early stage by limited temperature detection by a temperature sensor and which can be installed in an existing exhaust duct, and an alarm device.SOLUTION: Exhaust equipment which is installed in the middle of an exhaust duct, and which includes an exhaust fan 2 for making a gas inside the exhaust duct forcibly flow toward the outdoors includes: at least one upstream side temperature sensor 31a-31n installed in an upstream side duct 3; at least one downstream side temperature sensor 41a-41n installed in a downstream side duct 4; and a processing part 12 for calculating the temperature inside the duct on the upstream side and the temperature inside the duct on the downstream side, based on the value detected by these sensors, for comparing both temperatures from the calculation result, and for determining a fire based on the duration time in the case where a difference in both temperatures deviates from a predetermined range.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a device for detecting a fire in an exhaust duct in an exhaust facility installed in a factory, a restaurant, or the like, and a fire alarm device.

  Generally, a fire-proof damper is provided as a facility for a fire in the exhaust duct. This fire-proof damper has a structure in which the exhaust duct is closed to stop the movement of fire (see Patent Documents 1 and 2), and is configured to operate by blowing a thermal fuse. This thermal fuse has a fusing temperature that varies depending on the application where the exhaust duct is installed. In the case of a general ventilation system, it is 72 ° C, but in a kitchen exhaust system such as a restaurant, it is 120 ° C. The one at 280 ° C is used.

  The above-mentioned fire damper is mainly intended to prevent the propagation of a fire when the area subject to exhaust or ventilation becomes a fire, not to extinguish or calm the fire of the exhaust duct itself. However, for example, in an exhaust facility installed in a kitchen of a restaurant, oil or the like adheres to the exhaust duct, and the flame suddenly rises from oil such as a frying pan during cooking to adhere to the exhaust duct. In an exhaust system installed in a factory that performs welding or die casting, etc., dust accumulates in the exhaust duct, and dust that accumulates sparks scattered during processing. There were times when it ignited. For this reason, the exhaust duct itself could cause a fire. Therefore, a fire prevention device has been developed in the event that the exhaust duct itself fires (see Patent Documents 3 and 4).

Japanese Utility Model Publication No. 62-19881 Japanese Utility Model Publication No. 2-24018 JP-A-6-233833 JP 2001-12792 A

  In the fire protection devices disclosed in the above-mentioned Patent Documents 3 and 4, a temperature sensor or a thermal fuse is used as a fire detection means in the exhaust duct, but the part where the temperature sensor or the like is installed is used. By detecting the temperature, the fire was detected directly. As a matter of course, if an excessively high temperature can be detected by a temperature sensor or the like, it is possible to detect whether or not a fire has occurred from that temperature.

  However, since exhaust in restaurants and factories is performed over a relatively long section, the exhaust duct used is long, and many temperature sensors are installed to detect fires that occur in some of them. Had the problem of having to. In addition, in order to detect a fire in an exhaust duct that has already been installed, the existing exhaust duct will be partially cut and a temperature sensor etc. will be installed inside. It was not realistic to refurbish while using the exhaust duct.

  Also, if a fire occurs at a position that is not detected by a temperature sensor etc., the exhaust fan will be operated continuously, air will be constantly supplied, and the fire will be expanded. The fire could have spread to a wide area when detected by For this reason, an apparatus capable of detecting a fire at an early stage is eagerly desired. To that end, there is no means other than increasing the number of temperature sensors and the like.

  The present invention has been made in view of the above-mentioned points, and the object of the present invention is to detect fire at an early stage by temperature detection by a limited temperature sensor and can be installed in an existing exhaust duct. The object is to provide a fire detection system and an alarm device in an exhaust duct.

  Accordingly, the present invention relating to a fire detection system in an exhaust duct is an exhaust duct that is continuously arranged from the room to the outdoors, and is installed in the middle of the exhaust duct to force the gas in the exhaust duct to the outside. An exhaust system comprising an exhaust fan that is caused to flow downward, a detection system for a fire occurring in a part of the continuous exhaust duct, wherein at least one upstream temperature installed upstream of the exhaust fan A duct on the upstream side of the exhaust fan based on a value detected by the sensor, at least one downstream temperature sensor installed downstream of the exhaust fan, and the upstream temperature sensor and the downstream temperature sensor Calculate the internal temperature and the duct internal temperature on the downstream side, compare the temperatures of both from the calculation results, and the temperature difference between the two deviates from the predetermined range It is characterized in that and a fire determining processing section of the exhaust duct on the basis of the duration of the case.

  In the invention of the above configuration, the temperature sensor includes an exhaust duct installed on the upstream side of the exhaust fan (hereinafter sometimes referred to as “upstream duct”) and an exhaust duct installed on the downstream side (hereinafter referred to as “downstream”). 2) which are installed on both sides and divided into the installation locations, and detects fire from the difference in temperature detected by these two types of temperature sensors and the elapsed time It is.

  That is, a general exhaust duct is continuously arranged from the room to the outdoors, and an exhaust fan is installed in the middle of the exhaust duct to forcibly flow the room air to the outdoors. Accordingly, the air (gas) in the exhaust duct flows from the intake port toward the exhaust port, the negative pressure is upstream of the exhaust fan, and the positive pressure is downstream of the exhaust fan. Therefore, the duct internal temperature by the two types of temperature sensors is one of the upstream duct internal temperature and the other is the downstream duct internal temperature, and the air in the downstream duct that becomes positive pressure ( Since the gas is compressed and the temperature rises, the temperature in the duct on the downstream side is not less than the temperature in the duct on the upstream side. On the other hand, when a fire occurs in the upstream duct, the air (gas) in the upstream duct is heated, causing a reverse phenomenon in which the temperature is higher than the air (gas) in the downstream duct. In restaurants and factories, the reversal phenomenon of temperature difference continues because the air (gas) in the upstream duct may rise in the short term due to temporary flames or sparks. It can be determined that a fire has occurred.

  The invention of the above configuration detects a fire using the change and duration of the temperature condition, and compares the two types of duct temperatures, and the reverse phenomenon of the temperature difference is a predetermined time. When it is continued as described above, it is configured to determine whether a fire has occurred. As described above, since the fire is detected by detecting the temperature in the exhaust duct divided into the upstream side and the downstream side of the exhaust fan, the temperature sensor may be extremely limited. Easy installation.

  In the invention having the above-described configuration, the upstream temperature sensor is a temperature sensor installed in the vicinity of the suction port of the exhaust duct or the suction portion of the exhaust fan, and the downstream temperature sensor is an exhaust duct of the exhaust duct. It can be configured to be a temperature sensor installed either near the mouth or near the exhaust fan exhaust.

  In the case of the above configuration, when a relatively short exhaust duct is used, such as in a restaurant, the temperature inside the duct on the upstream side is near the inlet of the exhaust duct or the inlet of the exhaust fan, which is easy to install. The temperature in the duct on the downstream side can be measured either near the exhaust duct exhaust port or near the exhaust fan exhaust, so the temperature sensors to be installed are extremely limited. can do.

  In the invention with the above configuration, the upstream temperature sensor is a temperature sensor provided in the vicinity of the suction port of the exhaust duct and the suction portion of the exhaust fan, and the downstream temperature sensor is an exhaust gas of the exhaust duct. You may comprise so that it may be the temperature sensor provided in the vicinity of an opening | mouth and the exhaust part vicinity of an exhaust fan, respectively.

  In the case of the above configuration, since the calculation of the temperature in the duct on the upstream side is based on the temperatures detected in two places near the suction port of the exhaust duct and the suction portion of the exhaust fan, the temperature in the duct on the upstream side is It is calculated as the overall temperature while correcting each other. This makes it possible to correct the overall temperature when both locations are hot or cold. In particular, when installing an exhaust duct over a long distance, such as in a factory, the location where the intake port of the exhaust duct is installed is far away from the location where the exhaust fan is installed. The detected temperature due to the difference in location environment is corrected mutually. Note that it is possible to detect only one of the abnormalities by storing the temperature ranges of both at the normal time in advance. In this case, apart from the comparison result with the temperature in the duct on the downstream side, it is possible to detect a fire in the duct on the upstream side. The same applies to the detection of a fire at the duct internal temperature on the downstream side.

  Further, in the invention of each of the above configurations, the upstream temperature sensor further includes a temperature sensor provided as appropriate in the middle from the vicinity of the suction port of the exhaust duct to the vicinity of the suction portion of the exhaust fan, and the upstream side by the processing unit. The calculation of the duct internal temperature may be made based on the temperature detected by these temperature sensors.

  In the above configuration, a plurality of temperature sensors are installed in the exhaust duct on the upstream side, which enables correction when there is an external factor that induces a temperature change in the exhaust duct. It is. For example, by providing a temperature sensor at a position before and after the external factor is installed, values before and after the temperature change due to the external factor can be obtained, and the intake port of the exhaust duct and the intake part of the exhaust fan Even if there is a temperature difference between the two, the temperature difference can be treated as being due to the external factor. That is, when the heating means is installed close to the duct in the route of the exhaust duct, the temperature in the vicinity of the heating means rises, and conversely, when the cooling means is installed, Since the temperature in the vicinity of the cooling means is lowered, the upstream duct internal temperature can be corrected by detecting the rising / lowering state of the exhaust duct internal temperature by these heating means or cooling means.

  In the invention with the above configuration, the processing unit compares the temperatures at the installation locations detected by the plurality of temperature sensors installed as the upstream temperature sensors, and any temperature difference deviates from a predetermined range. Depending on the duration of the case, a fire between the two temperature sensors where the temperature difference has deviated may also be determined.

  According to the above configuration, the temperature change in the upstream duct can be subdivided and compared, and if the two temperature sensors compared are greatly different, a fire occurs between the two temperature sensors. It can be judged that it is doing. This can be processed when a temperature increase due to another factor is detected in consideration of the case due to the aforementioned external factor.

  In the invention of each of the above configurations, further includes an indoor temperature sensor provided in the vicinity where the intake port of the exhaust duct is disposed, and an outdoor temperature sensor provided outdoors where the exhaust port of the exhaust duct is disposed, The processing unit calculates the upstream duct internal temperature based on the temperature detected by the upstream temperature sensor and the indoor temperature sensor, and based on the temperature detected by the downstream temperature sensor and the outdoor temperature sensor. Thus, the temperature in the downstream duct can be calculated.

  According to the above configuration, the duct internal temperature can be corrected by a change in the indoor environment and a change in the outdoor environment. For example, in the case of a factory, the temperature environment in the room differs depending on the number of operations of processing devices such as welding machines installed in the room, etc. The correction is made within a range that affects the temperature of the air in the duct. Moreover, about the temperature in a downstream duct, the influence which the temperature environment by the outdoor temperature change etc. has can be correct | amended.

  On the other hand, the present invention relating to an alarm device for a fire in an exhaust duct uses any one of the detection systems having the above-mentioned configurations, and includes control means having the processing section, and the control means includes the temperature sensor. An input section for inputting the value of the above, a storage section for storing the temperature difference between the upstream duct temperature and the downstream duct temperature at normal times, and a signal for detecting and operating the operating state of the exhaust fan It is provided with the fan operation signal input / output part which inputs / outputs, and the alarm means for alerting | reporting the detection of a fire.

  According to the alarm device having the above configuration, whether or not the difference between the upstream duct temperature and the downstream duct temperature is caused by the operating state of the exhaust fan by detecting the operating state of the exhaust fan. Can be easily judged. That is, when the temperature in the upstream duct rises to the same level as the temperature in the downstream duct, and the exhaust fan stops due to a failure, etc., the temperature due to a cause other than the occurrence of a fire It can be judged as an increase. In addition, when a fire is detected (determined as a fire), the operation is controlled to stop the exhaust fan, and the supply of air from the indoor side is stopped to suppress the spread of the fire. it can. Further, by outputting to the alarm means, it is possible to notify the worker in the vicinity.

  In the invention having the above-described configuration, the temperature sensor includes transmission means for transmitting data wirelessly, and the exhaust fan transmits / receives an operation command wirelessly and transmits / receives an operation command wirelessly. The control means receives data transmitted from the temperature sensor and the exhaust fan, and transmits part or all of operation command information for the exhaust fan, alarm information for the alarm means, and control information. It is good also as a structure provided with a transmission / reception means.

  In the case of the above configuration, first, in a factory where a plurality of exhaust ducts are installed, the information of temperature sensors installed in each exhaust duct can be concentrated in one place, and in a large area factory The state of the exhaust duct can be managed collectively. In addition, since the information processed by the processing device is wirelessly transmitted, it is possible to detect the occurrence of a fire in the exhaust duct at the portable terminal even at a location away from the processing device. This can be confirmed even at a place away from the factory.

  According to the fire detection system of the present invention, it is possible to detect the occurrence of fire in air supply by temperature detection by a temperature sensor installed at a very limited position. Since the installation location of this temperature sensor can be limited, it can be easily installed in an existing exhaust duct. In particular, when the temperature sensor is installed only in the vicinity of the suction port and the exhaust port, no special work is required and the fire detection system can be used.

  In addition, according to the fire alarm device of the present invention, the exhaust fan can be automatically stopped as an initial operation based on the information detected by the fire detection system. In addition, by wirelessly transmitting the processing result by the processing device, the state of the exhaust duct can be widely known to field workers, and it can be confirmed not only by these field workers but also at remote locations. . Further, by storing the values of the temperature sensor and the input / output data relating to the operation command, it becomes possible to verify the fire at a later date. Furthermore, if only the temperature changes at the inlet and outlet of the exhaust fan are detected, it can also be used to detect the exhaust fan operating efficiency (exhaust capacity), such as the exhaust fan load status, aging status, etc. Can know.

It is explanatory drawing which shows embodiment of this invention which concerns on an alarm device. It is explanatory drawing which shows the 1st Embodiment of this invention which concerns on an alarm device. It is explanatory drawing which shows an example of the processing flow by a process part. It is explanatory drawing which shows the modification of the processing flow by a process part. It is explanatory drawing which shows the 2nd Embodiment of this invention which concerns on an alarm device. It is explanatory drawing which shows the processing flow which concerns on the temperature correction by a process part. It is explanatory drawing which shows the processing flow which concerns on the temperature correction by a process part.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. For convenience of description of the embodiment, an embodiment of the invention relating to an alarm device will be described first. FIG. 1 shows a system configuration diagram of an embodiment according to an alarm device. In the present embodiment, as shown in FIG. 1, various types of information are input to the control device 1 via the input unit 11 and processed by the processing unit 12, and a command is issued according to the processing result. Signals and other data are appropriately output via the output unit 13. In addition to the input information and the output information, a recording unit 14 that records various types of information such as appropriate time information is provided, and the processing unit 12 refers to the recorded information as necessary.

  The information input to the input unit 11 is information on the operation of the exhaust fan 2 disposed in the midway path of the exhaust duct, and the upstream duct 3 located on the upstream side and the downstream side with the exhaust fan 2 as a boundary. It is measured value information of each temperature sensor 31a-31n of the downstream duct 4, 41a-41n. The plurality of temperature sensors 31a to 31n installed in the upstream duct 3 detect the temperature at each position used for calculating the temperature in the duct on the upstream side, and the temperature sensors 41a to 41n of the downstream duct 4 are The temperature for calculating the temperature in the duct on the downstream side is detected. In addition, a temperature sensor 5 for detecting the indoor temperature and a temperature sensor 6 for detecting the outdoor temperature are arranged for the information input as the temperature information, and are referred to when calculating the temperature in each duct.

  On the other hand, the command output from the output unit 13 includes a notification command, a fan stop command, and the like. The notification command is output to the notification unit 7 when the processing unit 12 determines that there is a possibility of a fire in the duct. The notification means 7 is activated. At the same time, a stop command is output to the exhaust fan 2 to stop the operation of the exhaust fan 2. Stopping the operation of the exhaust fan 2 is to stop the supply of air into the exhaust duct. In addition, the information processed by the processing unit 12 and the command information can be output to the external server 8, and the external server 8 is accessed using a terminal carried by an individual. Thus, the environment of the duct internal temperature can be browsed, and the command information at the time of fire occurrence is automatically distributed from the external server 8 to the mobile terminal.

  In addition, when the process part 12 performs the process along the processing flow which is mentioned later among the said structures, a fire detection system will be comprised with each sensor 31a-31n and 41a-41n. Moreover, when comprising an alarm device, it can be abbreviate | omitted as needed. For example, regarding the output unit, only the notification means 7 may be used, and an operation for fire extinguishing may be performed by a fire extinguishing facility separately installed, and the external server 8 may be omitted and displayed on the display unit 15 of the control device 1. The situation may be confirmed by Further, the temperature sensor of the upstream duct 3 may be provided at only one location at the position where the temperature in the duct is most reflected, and the temperature sensor in the downstream duct 4 is the same. Further, the indoor temperature sensor 5 and the outdoor temperature sensor 6 may be omitted if it is not necessary to correct the temperature in the duct. The control device 1 is provided with an operation switch 16 so that the necessity of correction can be selectively operated, and the operation of each part at the time of operation / stop of the alarm device or inspection is performed. The state can be operated manually.

  Therefore, a specific embodiment according to the alarm device will be described. FIG. 2 is a layout diagram illustrating the first embodiment. As shown in this figure, the exhaust system has a configuration in which the exhaust ducts 3 and 4 are arranged so as to continue from the room to the outdoors, and the exhaust fan 2 is installed in the middle thereof. When smoke is emitted from a high-temperature facility (for example, a kitchen facility of a restaurant or a factory welding device) A provided in the room, the smoke is sucked from the suction port 30 and from the exhaust port 40 via both ducts 3 and 4. It discharges outdoors. In order to forcibly exhaust the internal air (gas) of the ducts 3 and 4, the ducts 3 and 4 are closed spaces, and the operation of the exhaust fan 2 brings the upstream duct 3 into a negative pressure state from the suction port 30. The downstream duct 4 is set in a positive pressure state, and the air is forcibly fed toward the discharge port 40.

  By the way, since the internal temperature of the exhaust ducts 3 and 4 increases due to the temperature of the exhausted smoke, it cannot be determined whether or not it is a fire even if only the increased temperature is detected. Therefore, in the present embodiment, the temperatures of at least two locations in the vicinity of the suction port 30a and the vicinity of the exhaust port 40a are compared. This is because, in the downstream duct 4, the internal air (gas) is compressed by the positive pressure and its temperature (T 2) rises, so it is compared with the temperature (T 1) of the internal air (gas) in the upstream duct 3. In a normal state (a state in which no fire has occurred in the upstream duct 3), the downstream duct temperature (T2) is slightly higher than the upstream duct temperature (T1) (T1 < T2).

  On the other hand, when a fire occurs in the upstream duct 3, the balance of the duct internal temperatures (T1, T2) is lost, and the upstream duct internal temperature (T1) is changed to the downstream duct internal temperature (T2). (T1 ≧ T2). By detecting such a reversal phenomenon, the occurrence of a fire can be detected early. Moreover, although the temperature balance (T1 <T2) is maintained in the discovery of the fire in the downstream duct 4, the difference between the two is assumed to be remarkably increased, so an upper limit of the temperature difference is set. Thus, the detection of the temperature difference exceeding the set value enables early detection of a fire in the downstream duct 4.

  Further, in the upstream duct 3, by providing a temperature sensor in the vicinity of the suction portion 30b of the exhaust fan 2, a fire in the upstream duct can be detected by measuring a temperature difference from the vicinity of the suction port 30a. Similarly, in the downstream duct 4, a temperature sensor can be provided in the vicinity of the discharge portion 40b of the exhaust fan 2, and a fire can be detected by a temperature difference from the vicinity of the exhaust port 40a. In normal operation, the internal temperature of the upstream duct 3 is substantially the same, and the same is true for the downstream duct 4, so that the occurrence of fire in the ducts 3 and 4 is detected when these temperatures differ greatly. can do.

  Here, the state of processing by the processing unit 12 when the detection value of the temperature sensor in each of the ducts 3 and 4 is input will be described. FIG. 3 is a diagram showing a processing flow. As shown in this figure, when the operation is started, first, a predetermined set value is read (S101). This set value is the above-described upper limit value of the duct internal temperature, an appropriate value of the difference between the internal temperature (T1) of the upstream duct 3 and the internal temperature (T2) of the downstream duct 4 or the like.

  After reading the set values, the detected values from the temperature sensors are input (S102), and the internal temperature T1, T2 is calculated while being divided into the upstream side and the downstream side (S103, S104). The calculation of the internal temperature is the detected value in the case of one sensor each, but when two or more sensors are installed, the internal temperature is divided into an upstream duct and a downstream duct. The detection value is input for each temperature sensor installed in the range, and the upstream duct internal temperature (T1) and the downstream duct internal temperature (T2) are calculated. The processing flow in this case will be described later.

  Using the duct internal temperature (T1, T2) calculated as described above and comparing both temperatures (S105), it is determined whether or not there is a fire. For the determination of the fire, if the comparison is an appropriate relationship (T1 <T2), it is not determined as a fire and the comparison (S105) is repeated from the temperature detection (S102). If it is reversed, it is determined whether or not the relationship is the first time, and time measurement is started in the first time (S106, S107). “First time” means a case where the first temperature difference reversal phenomenon is detected when the same state does not continue, and does not mean the first time in the entire period after the start of operation. On the other hand, if the above relationship has already been reversed (not the first time), it is determined whether or not the duration has exceeded the set (assumed) time (S108), and the set time is set. If it exceeds, it is determined that a fire has occurred and is notified (S108, S109). If the duration is less than the set time, it is regarded as a temporary temperature change, and the value input by the temperature sensor (S102) to the internal temperature comparison S105) are continued. If the temperature difference returns to an appropriate state at any timing during the period when the internal temperature is continuously compared, the time measurement will be reset, and if the temperature difference is not appropriate, the time measurement will be continued. .

  If at least the upstream duct internal temperature (T1) rises to the same level or higher as the downstream duct internal temperature (T2) by the above-described processing, an alarm is given that a possibility of a fire in the upstream duct is suspected. can do. Even if the temperature inside the duct on the upstream side rises due to other unexpected factors, it is possible to reduce the possibility of subsequent fire by removing the suspected factor by fire alarm. Become. Furthermore, in an initial fire that cannot be detected visually (state before ignition), it can be an opportunity to calm down in advance.

  Next, a processing flow when a plurality of temperature sensors are installed in the upstream duct and the downstream duct will be described. As shown in FIG. 2, the temperature sensor exemplified in this case is, for example, a case where the upstream duct 3 is provided with a temperature sensor in the vicinity of the suction port 30a and in the vicinity of the suction portion 30b of the exhaust fan 2, respectively. Yes, the downstream duct 4 is provided with temperature sensors in the vicinity of the exhaust port 40a and in the vicinity of the discharge part 40b of the exhaust fan 2, respectively. By these temperature sensors, the temperatures at both ends of the upstream duct 3 and the downstream duct 4 are detected, and a fire is detected in the ducts 3 and 4 belonging to any section by the temperature difference between the both ends. It will be possible.

  The processing flow in the above embodiment is shown in FIG. Also in this case, as shown in the figure, first, a preset set value is read by starting the operation (S201). Among these set values, in addition to the appropriate value of the difference between the internal temperature (T1) of the upstream duct 3 and the internal temperature (T2) of the downstream duct 4, the upper limit value of the temperature detected by each temperature sensor Etc. are included. After that, the detection value of each temperature sensor is input (S202), and the temperature at each point measured by each temperature sensor is compared and evaluated.

  Here, first, the detection value by the temperature sensor installed in the upstream duct 3 and the detection value by the temperature sensor installed in the downstream duct 4 are divided, and whether or not the temperature difference is appropriate for each division. Determination is made (S203, S204). That is, the temperatures of both ends 30a and 30b of the upstream duct 3 are compared to determine whether or not the difference is appropriate. The appropriate value is that the temperatures at the inlet (near the suction port 30a) and the outlet (near the suction part 30b of the exhaust fan) are almost the same. The appropriate range is, for example, the difference between the inlet temperature and the outlet temperature up to + 2 ° C. Can be set as When the outlet temperature is higher than the inlet temperature, there is a possibility that a fire has occurred in the middle (in the upstream duct), so that the detection of the fire is notified (S211). Even in the downstream duct 4, the temperatures of the inlet (near the exhaust fan discharge part 40 b) and the outlet (near the exhaust duct discharge port 40 a) are compared, and when the outlet temperature is higher than the appropriate range, This is reported as a fire in the downstream duct 4 (S211).

  Note that the temperature difference detection in this case may also be processed so that the duration is measured, and the occurrence of a fire is determined when the temperature difference continues beyond the set time. In addition, when the temperature difference is reversed between the inlet temperature and the outlet temperature, that is, when the inlet temperature is higher than the outlet temperature, it means that the vicinity of the inlet is high, but the inlet is frequently When the vicinity becomes high temperature, a correction is made between the corrected temperature and the outlet temperature by dealing with the temperature correction described later.

  When the difference between the inlet temperature and the outlet temperature of both ducts 3 and 4 is within an appropriate range, either one (both inlet temperature or outlet temperature) or the average value of both (both the inlet temperature and outlet temperature average) Temperature) is calculated as the upstream duct internal temperature (T1) and the downstream duct internal temperature (T2) (S205, S206), and by comparing the two (S207), further fire detection is performed ( S208 to S210). The comparison between the two is the same as the case of comparing the temperature in the duct (T1, T2) by each one temperature sensor described above. The duration is measured from the time when the balance of the temperature difference is reversed, and the set time is calculated. It is assumed that a fire has occurred when exceeding.

  It should be noted that the state where the balance of the temperature difference is reversed with respect to the internal temperature (T1, T2) of both the ducts although the temperature difference between the inlets and the outlets of both the ducts 3 and 4 does not occur is, for example, the upstream duct. 3 may be ignited, and there may be a case where the vicinity of the exit is ignited while the vicinity of the position entrance is always at a high temperature. Such a fire state as illustrated cannot be detected by a configuration in which a large number of temperature sensors are arranged, but can be detected by comparing the temperatures (T1, T2) in both ducts as in this embodiment.

  Since the two types of processing flows shown above are both cases where the internal temperature is not corrected, the relationship of the temperature difference (T1 <T2) may be disrupted due to an unexpected factor. When such a factor can be predicted, processing may be performed so that the duct internal temperatures (T1, T2) on both sides to be compared are corrected in advance.

  Then, next, an example in the case of performing temperature correction is shown. FIG. 5 is a layout diagram of each component assuming a case where temperature correction is to be performed. As shown in this figure, it is assumed that a device (external factor) B that can even change the temperature is installed in the middle path of the upstream duct 3. This figure exemplifies the air outlet of the air conditioner in order to make it easier to imagine both heating and cooling. However, external factors are not limited to equipment such as air conditioners, but the same applies when high temperature piping such as hot water or low temperature piping such as refrigerant is provided close to the exhaust duct. A case where equipment of the same type as equipment A (for example, kitchen equipment of a restaurant or a welding apparatus of a factory) A may be assumed. In order to detect a change in the temperature in the duct due to these external factors B, temperature sensors 30c and 30d are installed at positions before and after the external factor B. In addition, although illustration is abbreviate | omitted, when the same kind of external factor is installed in the downstream duct 4, a temperature sensor can be further installed also in the downstream duct 4.

  Further, in the illustrated example, when the suction port 30 is temporarily but frequently heated, for example, in the case of a kitchen facility in a restaurant, the detection temperature that frequently changes in the vicinity of the suction port 30a is corrected. In order to do so, a form is shown in which a temperature sensor 5 for detecting the temperature outside the duct (room temperature) in the vicinity of the high-temperature equipment A is provided. The indoor temperature sensor 5 may measure the overall indoor temperature and may be used as a correction for the entire upstream duct temperature. Similarly, by providing the outdoor temperature sensor 6 also outdoors, it can be used as a correction for the entire temperature in the downstream duct.

  FIG. 6 shows a processing flow with temperature correction when a temperature change due to the external factor B occurs with respect to the upstream duct internal temperature (T1). The illustrated processing flow shows a part of the whole. As shown in this figure, when calculating the duct internal temperature (T1) on the upstream side, first, the detection values of each temperature sensor are input (S202) in the same manner as the processing flow so far, The temperature change due to the target factor B is corrected (S301). As described above, since temperature sensors are respectively installed in the front and rear 30c and 30d of the duct arranged in the vicinity of the external factor B, the temperature is corrected by the temperatures detected by these temperature sensors.

  Prior to this correction, the temperature difference on the upstream side of the external factor is compared (S301), the fire in that section can be detected, and the temperature difference is also compared on the downstream side of the external factor (S302). Thus, it is possible to detect the holding of the section. If the temperature difference in each section exceeds the set range, it will be reported as a fire. As described above, when the temperature difference is normal at both the upstream side and the downstream side of the external factor, the temperature difference before and after the external factor is calculated (S303), and the upstream duct is calculated based on the temperature difference. Temperature correction is performed to compare the entire inlet temperature and outlet temperature (S304).

  As a specific method of temperature correction, when the external factor B is a heating device, the temperature in the duct rises by passing through the vicinity of the heating device. The temperature at the outlet (in the vicinity of the suction portion 30b of the exhaust fan) is higher than the temperature in the vicinity of the suction port 30a). Therefore, the temperature difference before and after the heating device is calculated by further subtracting from the temperature difference between the inlet temperature and the outlet temperature. Contrary to the above, when the external factor B is the cooling device, the temperature difference is added because the outlet temperature decreases. The inlet temperature and the outlet temperature can be compared based on the corrected temperature (S305). If the temperature difference exceeds the set temperature, a fire is reported. If the temperature difference is within the set temperature range, the upstream duct temperature (T1) is calculated based on the corrected temperature ( S205). The calculation of the duct internal temperature (T1) may be performed by using the corrected outlet temperature as the duct internal temperature (T1), and the duct internal temperature (T1) is obtained by averaging the values of all the temperature sensors installed in the upstream duct. May be calculated as

  Next, temperature correction in the vicinity of the suction port 30a and temperature correction in the vicinity of the discharge port 40a will be described. FIG. 7 is a diagram showing a processing flow for both temperature corrections. FIG. 7A shows temperature correction in the vicinity of the suction port 30a, and FIG. 7B shows temperature correction in the vicinity of the discharge port 40a. As illustrated in FIG. 5 (FIG. 5), a temperature sensor 5 for measuring the indoor temperature and a temperature sensor 6 for measuring the outdoor temperature are provided for correcting these temperatures.

  In the vicinity of the inlet 30a, for example, when a flame rises during cooking using a kitchen facility, the temperature may temporarily become high, and it is necessary to determine whether the temperature change is due to a fire in the duct or due to the cooking. There is. Therefore, the measured temperature is corrected while appropriately detecting the room temperature (particularly the temperature in the vicinity of the kitchen facility) (S401). That is, when a high temperature value is detected in the vicinity of the suction port 30a, if the indoor temperature is also detected at the same time, the temperature at that time is skipped instead of the suction port vicinity 30a. In addition, even if the temperature in the vicinity of the suction port 30a continues to be high, if the ambient temperature (room temperature) is high, it is considered a temperature change due to a factor different from the fire in the duct. Processing is performed so that a fire does not occur at the position near the suction port 30a. After performing such temperature correction, the inlet temperature and outlet temperature of the upstream duct are compared (S402), a fire is detected based on the temperature difference, and the upstream duct temperature (T1) is calculated. (S205).

  This also applies to the downstream duct. When the temperature in the vicinity of the exhaust port 4a rises due to an increase in outdoor air temperature, it is treated as a non-fire by comparison with the outdoor temperature sensor 6. . After the temperature correction (S501) in the vicinity of the exhaust port 40a, the inlet temperature and the outlet temperature of the downstream duct are compared to detect the occurrence of a fire, or the downstream duct internal temperature (T2) is calculated. Yes (S206).

  By calculating the temperatures in the upstream and downstream ducts (T1, T2) in a state where the temperature is corrected for the vicinity of the suction port 30a or the exhaust port 40a in this way, by further comparing the temperatures of the two, The occurrence of a fire in the duct is detected (S207 to S211) (see FIG. 4). The temperature correction in the vicinity of the suction port 30a can be processed together with the temperature correction due to the external factor.

  Although the embodiments of the present invention are as described above, each of the embodiments described above is an example, and the present invention is not limited to these embodiments. Therefore, various forms can be made within the scope of the gist of the present invention. For example, in the above embodiment, a fire is detected by using as few temperature sensors as possible. However, by arranging more temperature sensors than illustrated, a fire is generated due to a temperature difference between adjacent temperature sensors. It is good also as a structure which subdivides and detects a place. Further, the installation location of the exhaust fan 2 is not limited to the outdoors, and may be installed indoors. Furthermore, the upstream duct is not limited to a single path, and may be configured to branch into a plurality of paths and gather in the downstream duct.

  Moreover, although each said embodiment demonstrated centering on the alarm device of the fire in an exhaust duct, it was based on the temperature sensor installed in each place, and the process part processed based on the temperature detected by these temperature sensors. It is apparent from the gist of the present invention that a fire detection system in the exhaust duct can be configured.

1 Control Device 2 Exhaust Fan 3 Upstream Duct 4 Downstream Duct 5 Temperature Sensor (Indoor)
6 Temperature sensor (outdoor)
7 Informing means 8 External server 11 Input unit 12 Processing unit 13 Output unit 14 Recording unit 15 Display unit 16 Operation switch 30a Near suction port 30b Exhaust fan suction unit vicinity 30c, 30d Before and after external factors 31a, 31n Temperature sensor 40a Exhaust Near the mouth 40b Exhaust fan vicinity 41a, 41n Temperature sensor A High temperature equipment B External factors

Claims (8)

In an exhaust system comprising an exhaust duct continuously disposed from the room to the outdoors and an exhaust fan installed in the middle of the exhaust duct and forcibly flowing down the gas in the exhaust duct toward the outdoors. A detection system for a fire occurring in a part of the exhaust duct,
At least one upstream temperature sensor installed upstream of the exhaust fan;
At least one downstream temperature sensor installed downstream of the exhaust fan;
Based on the values detected by the upstream temperature sensor and the downstream temperature sensor, the temperature in the duct on the upstream side of the exhaust fan and the temperature in the duct on the downstream side are calculated, and the temperature of both is compared from the calculation result. And a processing unit for determining a fire in the exhaust duct based on a duration when the temperature difference between the two deviates from a predetermined range.   The upstream temperature sensor is a temperature sensor installed in the vicinity of the suction port of the exhaust duct or the suction part of the exhaust fan, and the downstream temperature sensor is in the vicinity of the exhaust port of the exhaust duct or the exhaust fan. The fire detection system in an exhaust duct according to claim 1, wherein the system is a temperature sensor installed in the vicinity of the section.   The upstream temperature sensor is a temperature sensor provided near the suction port of the exhaust duct and the suction portion of the exhaust fan, and the downstream temperature sensor is near the exhaust port of the exhaust duct and the vicinity of the discharge portion of the exhaust fan. The system for detecting a fire in an exhaust duct according to claim 1, wherein the temperature sensors are respectively provided in the exhaust duct.   The upstream temperature sensor further includes a temperature sensor appropriately provided in the middle from the vicinity of the suction port of the exhaust duct to the vicinity of the suction portion of the exhaust fan, and the calculation of the temperature in the duct on the upstream side by the processing unit The system for detecting a fire in an exhaust duct according to claim 3, wherein the detection is performed based on a temperature detected by the temperature sensor.   The processing unit compares the temperature at each installation location detected by a plurality of temperature sensors installed as the upstream temperature sensor, and determines the temperature difference according to the duration when any temperature difference deviates from a predetermined range. The fire detection system for an exhaust duct according to claim 3 or 4, wherein a fire between the two temperature sensors deviating from is also determined. Furthermore, an indoor temperature sensor provided in the vicinity where the intake port of the exhaust duct is arranged, and an outdoor temperature sensor provided outdoors where the exhaust port of the exhaust duct is arranged,
The processing unit calculates the duct internal temperature on the upstream side based on the temperatures detected by the upstream temperature sensor and the indoor temperature sensor, and based on the temperatures detected by the downstream temperature sensor and the outdoor temperature sensor. The exhaust duct fire detection system according to any one of claims 1 to 5, wherein a temperature in the downstream duct is calculated. A fire alarm device using the fire detection system in an exhaust duct according to any one of claims 1 to 6,
And a control unit having the processing unit, the control unit storing an input unit for inputting a value of the temperature sensor, and a temperature difference between the upstream duct temperature and the downstream duct temperature in a normal state. An exhaust duct, comprising: a storage unit that performs the operation, a fan operation signal input / output unit that inputs and outputs a signal for detecting and operating an operation state of the exhaust fan, and an alarm unit that notifies the detection of a fire. Internal fire alarm device. The temperature sensor includes transmission means for transmitting data wirelessly,
The exhaust fan includes a transmission / reception means for transmitting an operation command wirelessly and receiving an operation command wirelessly,
The control means receives data transmitted from the temperature sensor and the exhaust fan, and transmits / receives means for transmitting part or all of operation command information for the exhaust fan, alarm information for the alarm means, and control information. The alarm device for a fire in the exhaust duct according to claim 7, which is provided.

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