FIRE EXTINGUISHING SYSTEM AND METHOD FOR EXTINGUISHING A FIRE

Description

[0001] The invention relates to a fire extinguishing system and a method for extinguishing a fire. The fire extinguishing system comprises a plurality of sprinklers.

[0002] The sprinklers in a fire extinguishing system are typically designed to activate when a temperature threshold is exceeded. An extinguishing agent is then released from the system and combats the fire that caused the temperature increase.

[0003] Fire extinguishing systems are occasionally operated in areas where there is an airflow. This could be, for example, a warehouse if entrance gates are open at opposite ends. It could also be a tunnel if there is an airflow between the tunnel's ends.

[0004] A fire extinguishing system is known from DE 199 49 093 A1, in which, after the activation of one sprinkler, further sprinklers within and around a storage area are activated. A robot for fire fighting is known from JP H10 88997 A, which estimates and adjusts the trajectory of the extinguishing agent by means of position detection of a fire and based on environmental data.

[0005] The airflow causes a delay in heat generation, meaning that a sprinkler closer to the fire might not activate first, but rather one further away. This more distant sprinkler is not fully effective against the fire, which can delay fire suppression.

[0006] The invention is based on the objective of presenting a fire extinguishing system and a method for extinguishing a fire, with which a fire can be effectively fought even when an airflow exists in the area of ​​the fire extinguishing system. Starting from the aforementioned prior art, the objective is achieved by the features of the independent claims. Advantageous embodiments are specified in the dependent claims.

[0007] The fire extinguishing system according to the invention comprises a trigger sensor that sends a signal when a first sprinkler is triggered. A control unit processes the trigger sensor signal and a characteristic value of an airflow present in the area of ​​the fire extinguishing system to generate a control command that triggers a second sprinkler, comprising a flow meter for recording measurements of an airflow present in the area of ​​the fire extinguishing system. The control unit processes the measured value as a characteristic value of the airflow. The flow meter is designed to record a measurement of the direction and / or velocity of the airflow. The second sprinkler is arranged upstream of the first sprinkler with respect to the airflow present in the area of ​​the fire extinguishing system.

[0008] The invention is based on the understanding that, after a fire breaks out, the sprinkler closest to the source of the fire is not always the first to activate. The invention shortens the reaction time within which the fire extinguishing system develops its full effectiveness against the fire. By processing information about the airflow in the area of ​​the fire extinguishing system in the control unit, a second sprinkler located closer to the actual core of the fire can be activated after the first sprinkler has been triggered, before the temperature there has risen to the point where the second sprinkler activates due to exceeding the temperature threshold.

[0009] The characteristic value of the airflow in the area of ​​the fire extinguishing system, processed by the control unit, can be a value that is known in advance. This could be the case, for example, if the fire extinguishing system is installed in an area where a ventilation system generates a continuous airflow. Similarly, in a tunnel tube where vehicles move in one direction, there can be a substantially constant airflow. The characteristic value can be stored in a data memory of the control unit. The characteristic value can be a constant value. It is also possible for the characteristic value to change depending on environmental parameters, such as the time of day or the status of a ventilation system.

[0010] The fire extinguishing system includes a flow meter that measures the airflow within the system. These measurements are fed to the control unit as input and processed as a characteristic value of the airflow. This allows the fire extinguishing system to be controlled based on the actual airflow at any given time.

[0011] The flow meter can measure the direction of the airflow. This is particularly useful when the fire extinguishing system is operated in an area with airflows from varying directions. The control unit can then use this measurement to determine which second sprinkler in the fire extinguishing system should be activated.

[0012] Additionally or alternatively, the flow meter can be used to measure the airflow velocity. The greater the airflow velocity, the greater the heat generation offset and the greater the spatial distance between the first and second sprinklers. Information can also be derived from the airflow velocity measurement to determine which second sprinkler in the fire suppression system should receive the control command.

[0013] The fire extinguishing system can include multiple flow meters, which can be located in different sectors of the system. The control unit's data memory can store an assignment between flow meters and sprinklers. Based on this assignment, after the first sprinkler is triggered, the corresponding flow meter can be accessed to use its reading when determining the control command. It is also possible to calculate a combined reading from several flow meters, for example, by averaging, and use this combined reading in the control unit to determine the control command.

[0014] The control unit can process either a measurement of the airflow direction or a measurement of the airflow velocity to determine the control command. Alternatively, in areas where the airflow velocity is known or can be assumed to be constant, processing of the airflow velocity measurement can be omitted. Similarly, in areas where the airflow direction is known or can be assumed to be constant, processing of the airflow direction measurement can also be omitted.

[0015] The signal connection between the flow meter and the control unit can be, for example, a wired or wireless connection. The same applies to the signal connection between the trigger sensor and the control unit.

[0016] The trigger sensor signal can consist of the interruption of a signal connection that exists between the trigger sensor and the control unit when the fire extinguishing system is in standby mode. In one embodiment, the fire extinguishing system includes an electrical connection between the trigger sensor and the control unit, which is interrupted when the first sprinkler is triggered.

[0017] The control unit can include a data storage device containing information about the spatial position of the sprinklers in the fire extinguishing system. By processing the information about which sprinkler, as the first sprinkler according to the invention, was triggered, and by further processing the measured value from the flow sensor, a spatial area in which the fire may have broken out can be calculated. By comparing this spatial area with the information about the spatial position of the sprinklers stored in the data storage device, the control unit can determine for which sprinkler, as the second sprinkler according to the invention, the control command should be generated.

[0018] The fire extinguishing system can be configured such that, following the signal from the first sprinkler, a control command is generated for exactly one second sprinkler. In another embodiment, following the activation signal from the first sprinkler, a control command is generated for a group of sprinklers. Each sprinkler in the group constitutes a second sprinkler within the meaning of the invention. The method can be carried out in multiple stages if, following the activation signal from the first sprinkler and the control command to the group of second sprinklers, another first sprinkler is activated due to a temperature increase. This can trigger a further signal to the control unit, from which a control command for another group of second sprinklers is derived.

[0019] The fire extinguishing system can comprise a large number of sprinklers, for example, at least 10 sprinklers, preferably at least 20 sprinklers, and more preferably at least 50 sprinklers. All sprinklers of the fire extinguishing system, or some of the sprinklers, can be equipped with a trigger sensor. All sprinklers of the fire extinguishing system, or some of the sprinklers, can be configured to be triggered by a control command from the control unit.

[0020] The sprinklers can be connected to a fire suppression system's piping. The sprinklers in the piping system can be arranged in a single line, so that if all sprinklers in the line are activated, the extinguishing agent from the reservoir passes through each sprinkler in turn until it reaches the last sprinkler in the line. Alternatively, the piping system can be branched, with the sprinklers distributed across multiple lines. The piping system can be filled with extinguishing agent when the fire suppression system is in standby mode. It is also possible for the fire suppression system to be a dry system, in which case the piping is empty when the system is in standby mode.

[0021] In standby mode, the fire extinguishing system may be pressurized. The sprinklers may have a discharge opening that is closed in standby mode and open when the system is activated. When activated, the extinguishing agent is discharged from the pipe through the sprinkler. The sprinkler may include a release mechanism that keeps the discharge opening closed when the system is standby.

[0022] The sprinkler outlet may be sealed with a plug when the system is in standby mode, which is removed when the sprinkler is activated. The sprinkler's activation mechanism may hold the plug closed when the fire suppression system is in standby mode. When the sprinkler is activated, the activation mechanism can release the plug, causing it to be forced out of the outlet due to the pressure in the pipe.

[0023] The triggering element can be designed to react to heat. For example, the triggering element can be a fusible link that is solid at ambient temperature and melts when exposed to heat. Alternatively, the triggering element can be in the form of a glass bulb that shatters upon exposure to heat. In the standby state of the fire extinguishing system, the glass bulb can be supported between the plug and a spray plate of the sprinkler. The spray plate can be designed to deflect the extinguishing agent jet exiting the sprinkler outlet to the side. Preferably, the extinguishing agent is distributed substantially uniformly in all lateral directions.

[0024] The trigger sensor can include an electrical conductor path in which the triggering element is integrated. When the glass bulb breaks, the electrical conductor path is interrupted. This interruption can signal to the control unit that the sprinkler has been triggered. In one embodiment, the triggering element is a glass bulb with an electrically conductive coating, and the electrical conductor path is interrupted when the glass bulb breaks.

[0025] The control command that triggers the second sprinkler can be transmitted from the control unit to the second sprinkler, for example, via a wired or wireless connection. In one embodiment, there is an electrical circuit that extends from the control unit through the triggering element of the second sprinkler. By passing an electrical current through the circuit, the triggering element can be activated.

[0026] If the triggering element is a glass bulb with a coating of electrically conductive material, it can be heated by the electric current and shattered. The fire extinguishing system can be configured so that the sprinklers can be individually or in groups controlled by the control unit to activate them.

[0027] The fire suppression system can include a temperature sensor that measures the temperature at a sprinkler. This temperature reading can be sent to the control unit and used to determine control signals for triggering the sprinklers. For example, a temperature threshold can be set that is lower than the temperature threshold of the glass bulb, causing the sprinkler to activate earlier. This can be advantageous, for instance, when protecting goods with very low flash points. It is also possible, for example, to interpret a continuous temperature increase as an indication that the fire is approaching. The corresponding sprinkler can then be activated early.

[0028] The invention also relates to a tunnel equipped with such a fire extinguishing system. The tunnel can be designed for use by vehicles, for example, road vehicles and / or rail vehicles. The fire extinguishing system can comprise a plurality of sprinklers arranged one behind the other in the longitudinal direction of the tunnel. The predominant direction of airflow in tunnels is often known, for example, because the airflow is driven by vehicles moving through the tunnel in one direction. Corresponding information about the direction and speed of the airflow can be stored in the control unit. It is therefore possible, but not absolutely necessary, to continuously supply the control unit with current measured values ​​of the airflow in the tunnel.

[0029] The invention also relates to a method for extinguishing a fire. In this method, the state of a first sprinkler in a fire extinguishing system is monitored. If the activation of the first sprinkler is detected, a control command is generated to open a second sprinkler, comprising a flow meter for recording measurements of an airflow present in the area of ​​the fire extinguishing system. The control unit processes the measured value as a characteristic value of the airflow, the flow meter being designed to record a measurement of the direction and / or velocity of the airflow. The second sprinkler is arranged upstream of the first sprinkler with respect to the airflow present in the area of ​​the fire extinguishing system.

[0030] The extinguishing method can be further developed with additional features, which are described in connection with the fire extinguishing system according to the invention. The fire extinguishing system can be further developed with additional features, which are described in connection with the extinguishing method according to the invention.

[0031] The invention is described below by way of example with reference to the accompanying drawings and advantageous embodiments. The drawings show: Fig. 1: a tunnel with a fire extinguishing system according to the invention; Fig. 2: the fire extinguishing system made of Fig. 1 in enlarged view; Fig. 3: a schematic representation of a fire extinguishing system according to the invention; Fig. 4: a sprinkler of a fire extinguishing system according to the invention; Fig. 5: a schematic representation of an alternative embodiment of a fire extinguishing system according to the invention.

[0032] In Fig. 1 A railway tunnel 15 extends through a mountain 16, shown in cross-section. The railway line continues outside the tunnel on a bridge supported by stilts. The tunnel 15 is equipped with a fire extinguishing system comprising a pipe system suspended from the tunnel ceiling. An airflow, indicated by arrows 19, extends along the length of the tunnel 15.

[0033] According to Fig. 2 The fire extinguishing system comprises an extinguishing agent reservoir 20, a pump 21, and an unbranched pipe system in the form of a pipe 17. The pump 21 draws the extinguishing agent from the reservoir 20 and conveys it along the pipe 17. In a ready state, the pipe 17 is completely filled with extinguishing agent. The pump 21 maintains the pressure of the extinguishing agent.

[0034] Multiple sprinklers 18 are connected to pipe 17. Each sprinkler 18 has a discharge opening that is closed when the fire extinguishing system is in standby mode. If the temperature rises after a fire breaks out, a first sprinkler 19 is triggered, opening its discharge opening and allowing the extinguishing agent to flow from pipe 17 to combat the fire. Pump 21 continuously supplies extinguishing agent to maintain the flow of extinguishing agent from the first sprinkler 19.

[0035] In the example according to Fig. 2 The airflow 19 can cause a shift in heat generation. If a fire 22 breaks out in the tunnel 15, this shift in heat generation can lead to a situation where the sprinkler 23 located downstream of the fire 22, rather than the one directly above it, is the first to activate. The inventive method monitors which sprinkler 18 will be the first to activate after the fire 22 breaks out. A control command is sent to the second sprinkler 24 located upstream of the first sprinkler 23, causing the second sprinkler 24 to activate. Extinguishing agent is then also released through the second sprinkler 24, thus directly combating the fire 22.

[0036] In Fig. 3 The illustration is limited to a section of the pipeline 17 of the fire extinguishing system with a first sprinkler 23 and a second sprinkler 24. The fire extinguishing system includes a fire control unit 25, which is connected to each of the sprinklers 18 of the fire extinguishing system via electrical lines 26.

[0037] The sprinklers 18 of the fire extinguishing system include, according to Fig. 4 A glass bulb 27 holds a stopper (not shown) in position so that the outlet opening of the sprinkler 18 is closed. If the temperature exceeds a predetermined temperature threshold, the glass bulb 27 breaks and the outlet opening of the sprinkler 18 is released.

[0038] The glass bulb 27 is coated with an electrically conductive material. This electrically conductive coating is integrated into a circuit that extends as a closed conductor path from a sensor module 28 to the glass bulb 27 and back to the sensor module 28. The circuit is interrupted when the glass bulb 27 of the first sprinkler 23 breaks. The sensor module 28 detects the interruption of the circuit and sends a signal to a control unit 29. The sensor module 28 and the connected glass bulb 27 form a trigger sensor according to the invention.

[0039] After receiving the signal from the trigger sensor 27, 28, the control unit 29 sends a control command to a control module 30 to trigger the second sprinkler 24, which is located upstream of the first sprinkler 23. The control module 30 injects electrical current into the line 26 belonging to the second sprinkler 24 in order to heat the glass bulb 27 of the second sprinkler 24. The injection of electrical current continues until the temperature threshold of the second sprinkler 24 is exceeded and the glass bulb 27 shatters. The second sprinkler 24 is then also triggered, and the extinguishing agent is released from the second sprinkler 24 to act against the fire 22.

[0040] In the embodiment according to Fig. 5The fire extinguishing system comprises a branched pipe system with a plurality of pipe sections 31, each pipe section 31 being equipped with a plurality of sprinklers 18. Each sprinkler 18 is assigned a sprinkler controller 32, which communicates with the control unit 29 via a data network 33. An electrical circuit is provided between the sprinkler controller 32 and the glass bulb 27 of the associated sprinkler 18, through which the sprinkler controller 32 can, on the one hand, detect the state of the glass bulb 27 and, on the other hand, heat the glass bulb 27 to trigger the sprinkler 18.

[0041] When the sprinkler controller 32 detects that the corresponding sprinkler 18 has been triggered, a signal is sent to the control unit 29. A flow meter 34 is also connected to the control unit 29, providing it with measurements of the current airflow 19 within the fire extinguishing system. The control unit processes the measurements from the flow meter 34 and the signal from the sprinkler controller 32 of the first sprinkler 23 to determine which second sprinklers 24 are to be triggered by a control command. Information about the spatial arrangement of the sprinklers 18 relative to each other, stored in a memory of the control unit 29, is also retained during this process.

[0042] The control unit 29 is also equipped with an operating unit 35, which allows individual sprinklers 18 to be selectively triggered by user input.

Claims

1. Fire-extinguishing system having a plurality of sprinklers (18), having a trigger sensor (27, 28) which emits a signal in the event of a first sprinkler (23) being triggered, and having a control unit (29) which processes the signal of the trigger sensor (27, 28) and a characteristic value of an air flow present in the region of the fire-extinguishing system so as to generate a control command by way of which a second sprinkler (24) is triggered, a flow meter (34) for recording measurement values of an air flow present in the region of the fire-extinguishing system being comprised, wherein the control unit (29) processes the measurement value as a characteristic value concerning the air flow, wherein the flow meter (34) is configured to record a measurement value concerning the direction and / or the speed of the air flow, characterized in that, in relation to an air flow present in the region of the fire-extinguishing system, the second sprinkler (24) is arranged upstream relative to the first sprinkler (23).

2. Fire-extinguishing system according to Claim 1, characterized by a plurality of flow meters (34), wherein the flow meters (34) are arranged in different sectors of the fire-extinguishing system.

3. Fire-extinguishing system according to Claim 1 or 2, characterized in that, for the signal of the trigger sensor (27, 28), a signal connection present in a standby state of the fire-extinguishing system is interrupted.

4. Fire-extinguishing system according to one of Claims 1 to 3, characterized in that the control unit (29) is configured to generate, after the first sprinkler (23) has been triggered, a control command by way of which a plurality of second sprinklers (24) is triggered.

5. Fire-extinguishing system according to one of Claims 1 to 4, characterized in that the sprinklers (18, 23, 24) have an outlet opening, and in that, in the standby state of the fire-extinguishing system, the outlet opening is kept in a closed state by a trigger element (27).

6. Fire-extinguishing system according to Claim 5, characterized in that the trigger sensor (27, 28) comprises an electrical conductor path into which the trigger element (27) is incorporated.

7. Fire-extinguishing system according to Claim 5 or 6, characterized in that the trigger element (27) is a glass vessel provided with an electrically conductive coating.

8. Fire-extinguishing system according to one of Claims 1 to 7, characterized in that an electrical circuit is set up between the control unit (29) and the trigger element (27) of the second sprinkler (24) such that the control command of the control unit (29) acts on the trigger element (27) of the second sprinkler (24).

9. Tunnel having a fire-extinguishing system according to one of Claims 1 to 8.

10. Method for extinguishing a fire, in which the state of a first sprinkler (23) of a fire-extinguishing system is monitored, and in which a characteristic value of an air flow present in the region of the fire-extinguishing system is processed, so as to generate, after the first sprinkler (23) has been triggered, a control command by way of which a second sprinkler (24) is triggered, a flow meter (34) for recording measurement values of an air flow present in the region of the fire-extinguishing system being comprised, wherein the control unit (29) processes the measurement value as a characteristic value concerning the air flow, wherein the flow meter (34) is configured to record a measurement value concerning the direction and / or the speed of the air flow, wherein, in relation to an air flow present in the region of the fire-extinguishing system, the second sprinkler (24) is arranged upstream relative to the first sprinkler (23).