Fire detection device

Abstract

To obtain a fire detection device that can reduce the workload associated with draining condensation water. [Solution] The system comprises a cooling pipe, a trap that separates condensation water generated in the cooling pipe from the sampling air and stores the condensation water in a drain pipe, a smoke detection unit that performs fire detection processing based on the intake sampling air, an airflow sensor that detects a decrease in the flow rate of the sampling air as a decrease in flow rate, a drain valve that stores condensation water in the drain pipe when closed and drains the condensation water stored in the drain pipe when open, and a control unit that normally keeps the drain valve closed and opens the drain valve to drain the condensation water stored in the drain pipe when a decrease in flow rate is detected by the airflow sensor.

Description

Technical Field

[0001] The present disclosure relates to a fire detection device having a function of controlling drainage of condensed water stored in a cooling pipe.

Background Art

[0002] In a fire detection device that determines the presence or absence of smoke based on sampled air aspirated from a fire monitoring area, when the sampled air is at a high temperature, a method of cooling it to below the maximum allowable use temperature with a cooling pipe and then introducing it into a smoke detection unit is adopted (see, for example, Patent Document 1).

[0003] In the prior art described in Patent Document 1 that adopts this method, furthermore, a trap is provided in the cooling pipe in order to separate the condensed water generated in the cooling pipe from the sampled air after cooling.

[0004] With such a configuration, the fire detection device according to Patent Document 1 can prevent condensed water from being aspirated into the smoke detection unit and eliminate failures of the smoke detection unit caused by condensed water.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the method according to Patent Document 1 described above, although condensed water can be separated, there is a problem that the separated and stored condensed water needs to be drained manually.

[0007] Furthermore, when draining condensation water, it is often difficult to secure a separate drainage route, so in most cases, the accumulated condensation water is collected in a drain trap such as a bucket. Moreover, the amount of condensation water collected in the drain trap was checked visually and dealt with accordingly, making it a time-consuming task.

[0008] Therefore, although conventional fire detection devices have a mechanism to prevent condensation water from being drawn into the smoke detection section, draining the condensation water and checking the amount stored in the drain receptacle still requires manual labor, and there was a need to improve work efficiency.

[0009] This disclosure is made to solve the above-mentioned problems and aims to provide a fire detection device that can reduce the workload associated with draining condensation water. [Means for solving the problem]

[0010] The fire detection device according to this disclosure comprises a cooling pipe for cooling sampling air drawn in from a fire monitoring area, a trap for separating condensation water generated in the cooling pipe from the cooled sampling air that has passed through the cooling pipe and for storing the condensation water in a drain pipe, and a smoke detection unit for drawing in the cooled sampling air after the condensation water has been separated by the trap via a connecting pipe and for performing fire detection processing, and further comprises an airflow sensor that detects a state in which the flow rate of the sampling air has decreased to below a preset threshold as a flow rate reduction state, a drain valve attached to the drain pipe which, when closed, stores condensation water in the drain pipe and when open, drains the condensation water stored in the drain pipe, and a control unit that controls the opening and closing of the drain valve so as to keep the drain valve closed under normal circumstances and open the drain valve to drain the condensation water stored in the drain pipe when a flow rate reduction state is detected by the airflow sensor. [Effects of the Invention]

[0011] According to this disclosure, a fire detection device can be obtained that can reduce the workload associated with draining condensation water. [Brief explanation of the drawing]

[0012] [Figure 1] This is an explanatory diagram showing an example of the configuration of a fire detection device according to Embodiment 1 of this disclosure. [Figure 2] This is an explanatory diagram showing a detailed configuration of an example of the smoke detection unit shown in Figure 1 of Embodiment 1 of this disclosure. [Figure 3] This is an explanatory diagram showing an example of a configuration for realizing the condensation water drainage treatment function performed by the fire detection device according to Embodiment 1 of this disclosure. [Modes for carrying out the invention]

[0013] Hereinafter, preferred embodiments of the fire detection device of this disclosure will be described with reference to the drawings. The fire detection device according to this disclosure is characterized by its technical features, which enable automatic drainage of condensation water at an appropriate time, by comprising an airflow sensor that detects a decrease in the airflow of sampling air drawn into the smoke detection section, a drain valve that drains condensation water accumulated in the drain pipe, and a control unit that opens the drain valve in accordance with the detection result from the airflow sensor to drain the condensation water stored in the drain pipe.

[0014] In the following embodiments, we will refer to a specific example described in Patent Document 1, which uses high-temperature equipment as the target of fire detection. However, even for other fire detection targets where the problem of draining condensation water in cooling pipes occurs, the same effect can be achieved by applying the fire detection device according to this disclosure.

[0015] Embodiment 1. Figure 1 is an explanatory diagram showing an example of the configuration of a fire detection device according to Embodiment 1 of the present disclosure. The high-temperature equipment 10 that is the target of fire detection in Embodiment 1 is, for example, an oven used in a raw material drying process, and is constantly heated to 100°C.

[0016] On the upper part of the high-temperature machine 10, a duct 11 is provided, and the base end side 21 of a cooling pipe 20 with good thermal conductivity, such as copper, is connected to the duct 11. The cooling pipe 20 is formed in a bellows shape from the upper part to the lower part of the side surface of the outer wall of the high-temperature machine 10 and is arranged such that the base end side 21 and the terminal end side 22 communicate with each other. Although not shown, the cooling pipe 20 protrudes into the duct 11 to suck in the internal air flow, and a plurality of suction ports may be provided in the pipe extending into the duct 11.

[0017] The cooling pipe 20 is set to a predetermined length that can naturally air-cool the sampling air from the duct 11 to a temperature below the maximum allowable operating temperature of the smoke detection unit 30, for example, 60°C or below, and has a function of cooling the sampling air sucked from the fire monitoring area. By cooling this sampling air, the moisture contained in the sampling air is condensed.

[0018] A trap 23 for separating and storing the condensed water generated in the cooling pipe 20 from the sampling air is arranged at the terminal end side 22 of the cooling pipe 20. The trap 23 is connected to a communication pipe 24 and a drain pipe 25 as a condensed water storage part.

[0019] The trap 23 separates the condensed water generated in the cooling pipe 20 from the sampling air. In the specific example shown in FIG. 1, since the condensed water flows downward, the trap 23 is constituted by a branch pipe that separates the sampling air upward and the condensed water downward.

[0020] The condensed water separated by the trap 23 is stored in a drain receiver 27 through a drain pipe 25 to which a drain valve 26 is attached.

[0021] The communication pipe 24 is connected to a smoke detection unit 30 arranged on the upper side of the high-temperature machine 10. The sampling air after the condensed water is separated by the trap 23 is sucked into the smoke detection unit 30 through the communication pipe 24.

[0022] The smoke detection unit 30 corresponding to the smoke detection part that executes the fire detection process is a sampling type, and the allowable operating temperature range of the sucked air temperature is defined up to, for example, 50°C to 60°C. The exhaust side of the smoke detection unit 30 is connected to one end of the return air pipe 28, and the other end of the return air pipe 28 is connected to the duct 11.

[0023] The fire detection device according to the first embodiment has a technical feature in that the drain valve 26 is an electric valve that can be opened and closed under an external command, and includes an air flow sensor 40 that outputs a detection result according to the flow rate of the sampling air flowing through the communication pipe 24, and a control unit 50 that controls the opening and closing of the drain valve 26 according to the detection result by the air flow sensor 40. Therefore, this technical feature will be described next.

[0024] The air flow sensor 40 is a sensor that measures the flow rate of the cooled sampling air taken into the smoke detection unit 30 via the communication pipe 24, and outputs a state where the flow rate has decreased below a preset threshold value as a flow rate decrease state. The position for measuring the flow rate of the sampling air may be behind the trap 23.

[0025] When the amount of condensed water stored in the drain pipe 25 and the trap 23 exceeds the allowable amount, the sampling air passing through the trap 23 and flowing into the communication pipe 24 decreases, and a state occurs where the flow rate of the sampling air flowing through the communication pipe 24 and taken into the smoke detection unit 30 decreases. The drain pipe 25 may not be a straight pipe as shown in FIG. 1, and may have a storage part such as a bulge and be set to a predetermined capacity.

[0026] Therefore, when the control unit 50 detects a flow rate decrease state by the air flow sensor 40, it can switch the drain valve 26 from the closed state to the open state, drain the stored condensed water, and return the sampling air taken into the smoke detection unit 30 to an appropriate flow rate.

[0027] Furthermore, as will be described later using Figure 3, the airflow sensor 40 can also be a sensor that can output multi-stage flow rate reduction states.

[0028] Furthermore, the airflow sensor 40 can output the flow rate measurement result as an analog value, and the control unit 50 can be configured to use a threshold value to determine the flow rate reduction state.

[0029] The drain valve 26 is an electrically operated valve that can be opened and closed in response to commands from the control unit 50. The drain valve 26 is connected to the trap 23 via the drain pipe 25, and when closed, it can store condensed water in the drain pipe 25.

[0030] Furthermore, when the drain valve 26 is open, the condensed water stored in the drain pipe 25 can be drained into the drain receiver 27.

[0031] The control unit 50 controls the drain valve 26 to remain closed under normal conditions, thereby storing condensed water in the drain pipe 25 and drawing the sampling air into the smoke detection unit 30 without releasing it into the atmosphere, allowing it to operate as a fire detection device.

[0032] Furthermore, when the airflow sensor 40 detects a decrease in flow rate, the control unit 50 controls the drain valve 26 to open, thereby automatically draining the condensation water stored in the drain pipe 25.

[0033] Next, the configuration of the smoke detection unit 30 will be described with reference to Figure 2. Figure 2 is an explanatory diagram showing a detailed configuration as an example of the smoke detection unit 30 shown in Figure 1 in Embodiment 1 of this disclosure. The smoke detection unit 30 monitors abnormal smoke emission from the high-temperature equipment 10 and is composed of a suction fan 31, a dust filter 32, and a particulate matter detection unit 33.

[0034] By rotating the suction fan 31, the cooled sampling air is drawn in from the communication pipe 24, and the dust filter 32 removes dust from the drawn-in sampling air before supplying it to the particulate detection unit 33.

[0035] When filtered sampling air is supplied, the particulate detection unit 33 irradiates the smoke particles (particulate matter) contained in the sampling air with laser light and detects the total scattered light obtained therefrom with a photodetector, thereby detecting the amount of smoke particles (particulate matter) with high sensitivity.

[0036] In the fire detection device according to this embodiment 1, the high-temperature air from the duct 11 of the high-temperature equipment 10 is naturally cooled by the cooling pipe 20. The naturally cooled air is drawn into the smoke detection unit 30 via the trap 23 and the connecting pipe 24.

[0037] The smoke detection unit 30 determines that abnormal smoke emission has occurred in the high-temperature equipment 10 and a fire has broken out if the inhaled air contains more than a predetermined amount of smoke particles, that is, if the level of particulate matter detected by the particulate matter detection unit 33 is above the fire threshold, and outputs a fire signal to a fire receiver (not shown).

[0038] Furthermore, if condensation occurs inside the cooling pipe 20 during the process of natural cooling of the air inside the cooling pipe 20 by the outside air, this condensation is separated by the trap 23 and accumulates in the drain pipe 25. In other words, the condensation falls due to its own weight within the trap 23 and accumulates in the drain pipe 25.

[0039] At this time, the air inside the cooling pipe 20 is lighter, so it is drawn towards the connecting pipe 24 by the action of the suction fan 31.

[0040] On the other hand, condensation water accumulated in the drain pipe 25 can be stored in the drain receiver 27 by opening the drain valve 26. In particular, the fire detection device according to this embodiment 1 shown in Figure 1 is configured to include an airflow sensor 40, a control unit 50, and a drain valve 26 that can be opened and closed, thereby automating the drainage of condensation water and reducing the workload.

[0041] Furthermore, with this configuration, the control unit 50 can estimate the amount of condensation water stored in the drain receiver 27 and prompt the operator to drain the water from the drain receiver 27.

[0042] Specifically, the control unit 50 can perform the following series of processes to provide notification to encourage drainage processing of the drain receiver 27. Process 1: The control unit 50 counts the number of times the drain valve 26 is switched from the closed state to the open state as the number of drainage cycles.

[0043] Process 2: The control unit 50 estimates the amount of water stored in the drain receiver 27 according to the count of the number of drainage cycles, and if the estimated amount of water stored exceeds a preset threshold, it notifies that drainage treatment is necessary. Alternatively, the control unit 50 can also notify that drainage treatment is necessary when the number of drainage cycles reaches a preset number.

[0044] By receiving such notifications, operators can determine when to perform drainage treatment without having to visually check the amount of water stored in the drain receiver 27, thereby reducing the workload associated with draining condensate water.

[0045] Next, a specific example of a case in which an airflow sensor 40 capable of outputting multi-stage flow rate reduction states according to multiple thresholds is employed will be explained using Figure 3. Figure 3 is an explanatory diagram showing an example of a configuration for realizing the condensation water drainage treatment function performed by the fire detection device according to Embodiment 1 of this disclosure.

[0046] Figure 3 shows an example of a configuration for realizing a condensation water drainage function, consisting of an airflow sensor 40, a control unit 50, and a drain valve 26. The airflow sensor 40 shown in Figure 3 can detect the flow rate of sampled air flowing through the communication pipe 24 by dividing it into flow rate levels. It has a two-stage output function that detects a state in which the flow rate flowing through the communication pipe 24 decreases to a first threshold or below as a low-level flow rate reduction state, and a state in which the flow rate flowing through the communication pipe 24 decreases to a second threshold or below a value lower than the first threshold as a high-level flow rate reduction state.

[0047] Furthermore, the airflow sensor 40 can also be a multi-stage output level sensor, with levels that can be set in 10% increments. In this case, an appropriate level can be selected to identify low-level and high-level flow rate reduction states, and this can be read by the control unit 50 as a two-stage output.

[0048] The control unit 50 includes a valve opening / closing control unit 51 and a notification processing unit 52, and performs the following control processing in response to the two-stage output obtained from the airflow sensor. When the airflow sensor 40 detects a low-level flow rate decrease, the valve opening / closing control unit 51 controls the drain valve 26 to open, thereby draining the condensed water stored in the drain pipe 25.

[0049] Furthermore, if the valve opening / closing control unit 51 detects a high level of flow rate reduction by the airflow sensor 40, it instructs the notification processing unit 52 to output an alarm to notify that an airflow abnormality has occurred in the connecting pipe 24. This is because, while the accumulation of condensation water gradually increases, the airflow abnormality that requires an alarm results in a significant decrease in flow rate.

[0050] Receiving such a notification allows operators to quickly learn that the flow rate in the fire detection system's piping has decreased below the second threshold, potentially indicating an airflow anomaly within the system, and enabling them to take appropriate action.

[0051] As described above, Embodiment 1 provides a configuration that allows for automatic drainage of condensation water by detecting, using an airflow sensor, a decrease in airflow in the connecting pipe due to condensation. As a result, it eliminates the need for workers to visually check the amount of condensation water accumulating and to manually operate the drain valve to drain the condensation water, thereby reducing the workload associated with draining condensation water.

[0052] Furthermore, the system is designed to count the number of times water is drained and notify the user to prevent the drain pan from overflowing. As a result, the need to visually check the amount of water stored in the drain pan is eliminated, further reducing the workload associated with draining condensation water.

[0053] Furthermore, by employing an airflow sensor capable of producing multi-level output signals, a configuration is achieved that can notify of airflow abnormalities separately from the drainage of condensation water. As a result, it is possible to quantitatively evaluate whether the flow rate of the sampling air supplied to the smoke detection unit is normal, thereby ensuring the smoke detection performance of the fire detection device. [Explanation of symbols]

[0054] 10 High-temperature equipment, 11 Duct, 20 Cooling piping, 21 Base end, 22 Terminal end, 23 Trap, 24 Connecting piping, 25 Drain pipe, 26 Drain valve, 27 Drain receiver, 28 Return air piping, 30 Smoke detection unit, 31 Suction fan, 32 Dust filter, 33 Particulate matter detection unit, 40 Airflow sensor, 50 Control unit, 51 Valve opening / closing control unit, 52 Notification processing unit.

Claims

1. Cooling piping for cooling the sampled air drawn in from the fire monitoring area, A trap separates the condensation water generated in the cooling pipe from the cooled sample air that has passed through the cooling pipe, and stores the condensation water in a drain pipe. The smoke detection unit draws in the cooled sampled air, after the condensation water has been separated by the trap, through a connecting pipe, and performs fire detection processing. A fire detection device equipped with, An airflow sensor that detects a state in which the flow rate of the sampled air decreases to below a preset threshold as a flow rate reduction state, A drain valve is attached to the drain pipe and, when closed, stores the condensed water inside the drain pipe, and when open, drains the condensed water stored in the drain pipe. A control unit controls the opening and closing of the drain valve, which normally keeps the drain valve closed, and opens the drain valve to drain the condensed water stored in the drain pipe when the airflow sensor detects a decrease in flow rate. A fire detection device that also includes additional features.

2. The system further includes a drain receiver for storing the condensed water drained from the drain valve, The control unit, The number of times the drain valve is switched from the closed state to the open state is counted as the number of drainage cycles. The amount of water stored in the drain receiver is estimated according to the counting result of the number of drainage cycles. If the storage volume exceeds a certain threshold, a notification will be issued indicating that wastewater treatment is necessary. The fire detection device according to claim 1.

3. The airflow sensor is capable of detecting the flow rate of the sampled air flowing through the connecting pipe by dividing it into flow rate levels. The control unit, If the airflow sensor detects a low-level flow rate reduction, the drain valve is opened to drain the condensed water stored in the drain pipe. If the airflow sensor detects a high level of flow rate reduction, it will notify that an airflow abnormality has occurred in the connecting piping. The fire detection device according to claim 1 or 2.

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