A Fire Fighting System for Extinguishing a Fire in a Room of a Building, A Method Thereof and Use of an Array Sensor Therein

Abstract

The invention relates to a fire fighting System (1) for extinguishing a fire in a room (101) of a building (100), comprising at least one stationary fire locator device (7) configured to locate a fire (F), a plurality of stationary fire fighting devices (3a, b), each associated with and configured to distribute fire extinguishing fluid within a respective zone (11a,b) of the room (101), and a Controller (9) that is in Signal communication with the at least one locator device (7) and with the extinguishing devices (3a, b). In a preferred embodiment the invention is configured to activate at least one of the extinguishing devices (3a, b) in reaction to identifying the fire (F); wherein the at least one locator device (7) comprises an array sensor (19), said array sensor (19) having a plurality of pixels that are sensitive to electromagnetic radiation, and arranged in a grid (17) of pixels, wherein each pixel is associated with a specific portion of the room, the Controller (9) is configured to locate the zone of the room (101) having the fire (F) by identifying hot spots formed by those pixels which sense electromagnetic radiation exceeding a predetermined threshold level (T.sub.1), and to activate the at least one fire fighting device (3a, b) associated with the located zone.

Claims

1. A fire fighting system for extinguishing a fire in a room of a building, comprising: at least one stationary fire locator device configured to locate a fire, a plurality of stationary fire fighting devices, each associated with and configured to distribute fire extinguishing fluid within a respective zone of the room, and a controller that is in signal communication with the at least one locator device and with the extinguishing devices, and is configured to activate at least one of the fire fighting devices in reaction to identifying the fire; wherein the at least one locator device comprises an array sensor, said array sensor having a plurality of pixels that are sensitive to electromagnetic radiation, and arranged in a grid of pixels, wherein each pixel is associated with a specific portion of the room, and wherein the controller is configured to: locate the zone of the room having the fire by identifying hot spots formed by those pixels which sense electromagnetic radiation exceeding a predetermined threshold level, and activate the at least one fire fighting device associated with the located zone.

2. The fire fighting system of claim 1, wherein the controller is configured to allocate specific threshold values to each pixel.

3. The fire fighting system of claim 1, wherein the pixels are sensitive to at least one of: ultraviolet light, visible light, or infrared light.

4. The fire fighting system of claim 1, wherein the array sensor is a thermopile array sensor, each pixel comprising a thermopile element.

5. The fire fighting system of claim 1, further comprising at least one fire detector device in addition to the fire locator device, the fire detector device being selected from the list consisting of: smoke detector, optical beam smoke detector, aspiration smoke detector; flame detector, IR flame detector, UV flame detector, combined IR/UV flame detector; heat detector; gas detector; or multi-sensor-detector.

6. The fire fighting system of claim 5, wherein the at least one fire detector device is configured to generate a signal indicative of the presence of the fire in the room, and the controller is configured to activate the at least one fire fighting device only when the at least one fire detector device has indicated the presence of the fire, and the controller has located the zone having the fire based on the signals received from the fire locator device.

7. The fire fighting system of claim 4, wherein the at least one fire locator device comprises a plurality of fire detector devices.

8. The fire fighting device of claim 1, wherein the fire locator device comprises a microprocessor that is configured to determine the temperature in each portion of the room associated with a respective one of the pixels and generate a signal representative of said temperatures.

9. The fire fighting system of claim 1, each of the fire fighting devices having a controlled trigger that is configured to activate a flow of extinguishing fluid from the fire fighting device upon receipt of an activation signal; and the controller being configured to generate said activation signal as a function of identifying and locating the fire.

10. The fire fighting system of claim 1, wherein the plurality of fluid extinguishing devices are positioned and arranged in the room so as to respectively cover a zone of predetermined size, the controller being configured to locate the zone containing the fire, and a) if only one fire fighting device is positioned to cover the zone having the fire, to activate only that respective extinguishing device, or b) if several fire fighting devices are positioned to cover the zone having the fire, to activate no more than two fire fighting devices covering the zone having the fire.

11. The fire fighting system of claim 1, the room having a wall, a ceiling and a floor, wherein the at least one fire locator device is mounted to the wall or ceiling of the room and has a defined field of view directed towards the floor of the room, each of the pixels being associated with a segment of said field of view, such that each pixel covers a specific portion of the floor of the room.

12. The fire fighting system of claim 1, wherein the fire fighting system is a deluge system, and the fire fighting devices respectively comprise an open extinguishing nozzle including one of: full cone spray nozzles, open side wall sprinkler type nozzles, or open nozzles with a flat spray pattern.

13. The fire fighting system of claim 1, wherein the fire fighting system is a water based extinguishing system, and the fire fighting device respectively comprises a controllable sprinkler, activated by the controlled trigger.

14. The fire fighting system of claim 13, wherein the controllable sprinkler is designed as an electrically activatable sprinkler, or a nozzle cooperating with or comprising a sealing device which is configured to open to discharge a fire extinguishing fluid in response to receiving an electrical signal.

15. A method of extinguishing a fire in a room of a building, comprising the steps of: locating a zone of the room having a fire with at least one stationary fire locator device by sensing electromagnetic radiation with a grid of pixels of an array sensor, wherein each pixel is associated with a predetermined specific portion of the room, identifying hot spots formed by those pixels which sense electromagnetic radiation exceeding a predetermined threshold level; and distributing an extinguishing fluid from at least one of a plurality of stationary fire fighting devices to the located zone.

16. The method of claim 15, comprising: defining the location of stationary hot spots that are indicative of fire-unrelated heat sources by allocating specific threshold values to each pixel.

17. The method of claim 15, wherein the sensing of electromagnetic radiation comprises sensing of at least one of: ultraviolet light, visible light, or infrared light; and comprises sensing heat radiation with a thermopile array sensor, each pixel of the sensor comprising a thermopile element.

18. The method of claim 15, further comprising the step of detecting the presence of the fire with at least one fire detector device selected from the list consisting of: smoke detector, optical beam smoke detector, aspiration smoke detector; flame detector, IR flame detector, UV flame detector, combined IR/UV flame detector; heat detector; gas detector; or multi-sensor-detector.

19. The method of claim 18, comprising a step of generating a signal indicative of the presence of the fire in the room, and activating the at least one fire fighting device only when the presence of the fire has been indicated by the at least one fire detector device, and the zone having the fire has been located based on the signals received from the fire locator device.

20. The method of claim 15, wherein the plurality of fluid extinguishing devices are positioned and arranged in the room so as to respectively cover a zone of predetermined size, the method further comprising: locating the zone containing the fire, and a) if only one fire fighting device is positioned to cover the zone containing the fire, activating only that respective extinguishing device, or b) if several fire fighting devices are positioned to cover the zone containing the fire, activating no more than two fire fighting devices covering the zone having the fire.

21. (canceled)

Description

[0075] Hereinafter, preferred embodiments of the invention will be described with reference to the accompanying drawings in greater detail. Herein,

[0076] FIG. 1 shows a schematic view of a fire fighting system according to a preferred embodiment,

[0077] FIG. 2 shows a schematic detail view of the system according to FIG. 1,

[0078] FIG. 3a, b show a schematic detail view of an array sensor used in the system of FIGS. 1 and 2.

[0079] FIG. 4 a schematic view of a first example of zones in a room,

[0080] FIG. 5 a schematic view of a second example of zones in a room,

[0081] FIG. 6 a schematic view of a third example of zones in a room,

[0082] FIG. 7 a schematic view of a fourth example of zones in a room,

[0083] FIG. 8 a schematic detail view of a fire fighting system,

[0084] FIG. 9 a schematic view of the system of FIG. 8 in a room, and

[0085] FIG. 10 schematically and exemplarily a flow chart of a method for fire fighting of a room.

[0086] FIG. 1 shows a fire fighting system 1. The fire fighting system 1 is installed in a room 101 of a building 100. The room comprises a number of walls 103, a ceiling 105 and a floor 106. Inside the room 101, a heat source 107 is installed.

[0087] It should be noted that, while an entire room 101 is illustrated in FIG. 1 and some of the consecutive figures, the system according to the invention can also be provided to protect only a part of the room. In this case, also a plurality of systems 1 according to the invention can be provided to protect the entire room. Thus, a room according to this invention is used as a defined space under protection by fire fighting system 1, which can also be a part of a physical room, i.e. a construction being enclosed by walls and ceiling.

[0088] The system 1 comprises a number of fire fighting devices 3a, b which are installed for example under the ceiling 105 of the room 101, but could alternatively also be wall-mounted. The fire fighting devices 3a, b may for example be open extinguishing nozzles of a deluge system.

[0089] The system 1 further comprises a plurality of fire detection devices 5a, b installed in the room 101, for example under the ceiling 105 and/or on one of the walls 103.

[0090] The system 1 further comprises a fire locator device 7 that is configured to locate a fire F in the room 101. The fire detector devices 5a, b are configured to detect the presence of a fire in the room 101. The fire fighting devices 3a, b are each positioned such that they distribute fire extinguishing fluid within a respective coverage zone 11a, b (hereinafter also “zone”) of the room 101. The zones 11a, b may overlap.

[0091] System 1 further comprises a controller 9 which is in signal communication with the fire fighting devices 3a, b with the fire detection devices 5a, b and with the fire locator device 7. The controller 9 is configured to activate the fire fighting devices 3a, b in reaction to a detection of the fire F as is detailed further herein below.

[0092] The fire locator device 7 comprises an array sensor 19 (FIGS. 3a, b) which has a defined field of view having a first view angle α1, e.g. a vertical angle, and a second view angle α2, e.g. a horizontal angle. (FIG. 2). Within its field of view, the array sensor 19 is adapted to monitor a predetermined area of the room 101. The array sensor 19 comprises a sensor array 15 having a plurality of n x m pixels arranged in a grid 17. Since the fire locator device 7 is stationary, i.e. fixedly installed in the room 101, once oriented, each of the pixels of the grid 17 is specifically assigned to a specific portion of the room 101. Depending on the distance of the fire locator device 7 from e.g. the floor 106 of the room 101 and depending on the specific view angles α1, α2, the grid 17 of pixels defines a projection 13 of the pixel grid 17 in the room 101, and in the embodiment shown in FIG. 1, encompassing a portion of the floor 106 of the room 101. A fire F which lies within this projection 13 will be detected by the grid 17 of the sensor array 15.

[0093] Preferably, the sensor array 15 is an infrared sensor array, in particular a thermopile array. The array sensor 19 is configured to permanently generate for each pixel a signal representative for a temperature within the portion of the projection 13 in the room 101. The fire F will cause representative temperature signals to be generated by the array sensor 19. The controller 9 is configured to receive the representative temperature signals from the array sensor 19. Also, the controller 9 is configured to allocate specific threshold values T.sub.1, T.sub.2 to each pixel of the sensor array 15. There may be two or more different threshold values used across the array. According to the invention, it is possible to designate a threshold value that will be reached only in case of a fire, or not be reached at all, the latter being especially useful to permanently “blind” the array sensor from certain stationary hot spots that are indicative of non-fire related heat sources.

[0094] However, each threshold value may also be indicative of a temperature limit, the breach of which happens only in case of a fire in that specific portion of the room. As soon as the temperature in the pixels of the sensor array 15 exceeds the predetermined threshold levels T1, T.sub.2, the controller not only has identified the presence of a fire F in the room 101, but additionally has located the portion within the projection 13 where the fire F recites by identifying the respective hot spot among the grid 17 of pixels. This allows for very efficient allocation of the fire fighting device 3a or 3b that is ideally positioned to distribute extinguishing fluid in the zone where the fire F has been located. Depending on whether the fire has been located in a zone that is overlapped by the zones 11a, b of a plurality of fire fighting devices 3a, b, the controller 9 may also activate more than one fire fighting device 3a, b, but ideally no more than two fire fighting devices 3a, b.

[0095] In many rooms, in particular residential rooms, it is to be expected that stationary heat sources such as heat source 107 are present in a portion of the room monitored by the fire locator device 7. In order to prevent false fire alarms, and in order to prevent inaccurate location of actual fires due to the influence of stationary heat sources, the controller 9 is configured to assign specific threshold values T.sub.2 to all pixels which are within range of the stationary hot spot 109 formed by the stationary heat source 107. As is depicted in FIG. 2 and FIG. 3b, the controller 9 could for example be programmed to assign a higher threshold value T.sub.2 to pixels 49 through 54 and 57 through 62, while assigning a lower threshold value T.sub.1 to the remaining pixels of the grid 17. By doing so, increased radiation emanating from heat source 107 would not be flagged as hotspots indicative of a fire F, unless the predetermined higher threshold value T.sub.2 is exceeded.

[0096] This allows the controller 9 to distinguish between a fire F and a fire-unrelated heat source NF. Basically, any number of stationary heat sources may be accounted for in this way.

[0097] While the embodiments of FIGS. 1 through 3b show a simple set-up of a room 101 having only one fire locator device, the invention also covers embodiments wherein the room 101, either due to its size or due to its complexity of its layout, requires the use of more than one fire locator device. Preferably, the entire floor 106 of the room is covered by projections 13 of the grids 17 of pixels of specifically mounted and oriented fire locator devices 7. Depending on economic factors and ease of installation, the number of fire locator devices for the size of the grid 17 of pixels for each fire locator device 7 may be modified according to need. At any rate, the invention allows for the use of array sensors 19 having sensor arrays 15 with comparatively low resolution (in particular when compared to prior art systems using high-res infrared camera systems).

[0098] FIGS. 4 to 7 schematically and exemplarily illustrate different configurations or distributions of zones 210a-210e or 310a-310h in different rooms, respectively.

[0099] FIG. 4 illustrates a layout of four zones 210a-210d, which are equal in size and apportion the surface area of the room among them. In other words, the four zones 210a-210d cover the entire surface area, i.e. the floor and—if necessary—at least part of the wall surface area of the room. A further, fifth zone 210e is located in the center of the room and overlays all of the other four zones in the center of the room. Fifth zone 210e is thus redundant and provided to limit the spacial extension and also the amount of the fire extinguishing fluid dispersion.

[0100] In FIG. 4, four examples of a fire F at different locations within the illustrated room, i.e. within different zones 210a-210e, are illustrated. Each of the examples of the fire F leads to the determination of an fire fighting area 220 by the controller 9, which is as follows. In the first example, since the fire F is located within zone 210a, the fire fighting area is determined to be comprised of zone 210a. In the second example, the fire F is located at the edge between zone 210a and zone 210b, such that both zone 210a and zone 210b are determined as the fire fighting area 220. The third example shows the fire F in the center of the room. In this example, only zone 210e is determined as fire fighting area 220. In the last example, the fire F is located close to the center within zone 210b. Thus, both the central zone 210e and zone 210b are determined as fire fighting area 220. In these examples, for the reasons discussed above, it is preferred that not more than two zones 210a-210e be determined as fire fighting area 220.

[0101] In this example, both the room and each of the respective zones 210a-210e are of quadratic shape for the ease of illustration, while of course also different examples of shapes are contemplated. The quadratic shape is particularly beneficial in combination with specific controllable nozzles as fire fighting devices, e.g. fire fighting device 3a-3e, such as a Viking Model A full cone nozzle or a similarly operating, publically available nozzle.

[0102] FIG. 5 substantially corresponds to the example of FIG. 4, wherein the room—or likewise a part of the room—is rectangular and its surface is distributed among six zones 310a-310f, which are also in this example quadratic and of equal size. Two central zones 310g and 310h are respectively provided to overlap four adjacent of the zones 310a-310f, respectively. The determination of a fire fighting area 220 is performed analogous to the example of FIG. 4. In other word, not more than two zones 310a-310h are determined to be part of the fire fighting area (not shown in FIG. 5) at the time.

[0103] FIG. 6 schematically illustrates a further example, wherein the room is split into two substantially independent regions of five zones 210a-210e, 310a-310d and 310g, respectively. For examples, each of the two groups of five zones can be coordinated and controlled by a particular, individual controller 9 and/or fire locator device 7. In other examples, the two groups can also be controlled commonly by a single controller 9 and/or fire locator device 7.

[0104] In the example of FIG. 6, the two fully overlapping regions 210e, 310g are not adjacent to each other, different from the example of FIG. 5, in which two completely overlapping zones 310g, 310h are adjacent to each other. In the example of FIG. 6 a fire F is illustrated in the center of the room. In this example, the fire fighting area 220 is extended to include two zones 210b, 210d, and 310a, 310c of each of the first and second group of zones 210, 310, respectively.

[0105] Accordingly, in this example also the situation, in which more than two zones are comprised in the fire fighting area 220 is illustrated. The example of FIG. 6 is particularly useful in case two substantially independent systems for fire fighting are arranged in the same room. In this case, two zones per independent system are comprised in the fire fighting area 220, respectively. Then, again, not more than two zones will be activated concurrently, i.e. designated as the fire fighting area 220.

[0106] It is of course contemplated that also in the example of FIG. 6 a further fully overlapping zone can be defined in between the zones 210e and 310g. In this particular case, it would be beneficial to protect the entire room as illustrated in FIG. 6 with a single system for fire fighting according to the invention.

[0107] FIG. 7 schematically and exemplarily illustrates the effect of overlapping zones in the example of five zones 210a-210e. In this example, overlapping regions 212a-212k are formed in the overlapping area between two adjacent zones 210a-210e, respectively.

[0108] Overlapping regions 212a and 212b correspond to the region in which zone 210a overlaps zone 210b and vice versa. Accordingly, the fire fighting area 220 in case a fire F is detected in either region 212a or region 212b will be comprised of both zone 210a and 210b. Likewise, in overlapping regions 212c and 212d zones 210a and 210c will form the fire fighting area 220. A fire F in overlapping region 212e or 212f will yield a fire fighting area 220 with zones 210c and 210d, while a fire F in overlapping region 212g or 212h will result in fire fighting area 220 being formed of zones 210b and 210d.

[0109] Finally, in case a fire is present in the outer region of zone 210e, i.e. the region near the edge of zone 210e, which are indicated with 212i, 212j, 212k or 212l, the fire fighting area 220 is formed of zone 210e and one of zones 210a-210d, respectively. Thus, also in this example with overlapping regions, it can be ensured that not more than two zones will be comprised in the fire fighting area 220 at the same time.

[0110] FIG. 8 and FIG. 9 schematically and exemplarily illustrate a further example of the system 1 according to, for example, FIG. 1. In FIG. 8, it can be particularly seen that a fire locator device 7 is mounted at or on the side wall 103 or the room 101.

[0111] The fire locator device 7 comprises, not shown in detail, the array sensor 19. Further, in this example, fire locator device 7 is mounted together with five controllable nozzles, i.e. fire fighting devices 3a, 3b, 3c, 3d, 3e. Preferentially, at least the fire fighting devices 3a, 3b, 3c, 3d, 3e and the fire locator device 7 are mounted on or in a single housing, while in other examples also at least two housings can be provided for the respective components. Each of the five fire fighting devices 3a, 3b, 3c, 3d and 3e can be corresponded to, for instance, one of five zones, respectively.

[0112] Finally, two additional fire detection devices 5a, 5b are provided. The location of the fire detection devices 5a, 5b is of course only an example and also different locations within the room 101 are contemplated.

[0113] In particular, fire detection device 5a, for instance a smoke detector, is illustrated near the center of room 101 and used as a double interlock safety feature, i.e. the fire fighting devices 3a-3e, 3c, 3d, 3e are only operated by controller 9 in case also at least one of the additional fire detection devices 5a and 5b detects a fire in the room 101. The second additional fire detection device 5b can also be a smoke detector or any other detector, which is preferentially arranged to detect a fire within the room 101. In contrast to fire detection device 5a, fire detection device 5b is mounted nearby fire locator device 7, thereby facilitating mounting of the entire system 1.

[0114] FIG. 9 illustrates the example of FIG. 8 in a different scale. In particular, it can be seen in FIG. 9 that different fire fighting devices 3a, 3b and even 3c are provided with a different orientation α1, α2, α3 with respect to the direction of side wall 103. The number of three fire fighting devices 3a, 3b, 3c is of course not limited and can be more or less than three. Further, also in the other examples illustrated above more or less fire fighting devices can be provided.

[0115] FIG. 10 schematically and exemplarily illustrates a flowchart of a method 400 for fire fighting of a room, such as room 101 discussed above, using system for fire fighting, such as system 1 discussed above.

[0116] The system 1 particular comprises one or more fire locator devices 7 mounted on at least one of a wall 103 and a ceiling 105 of the room 101. Each of the fire locator devices 7 comprises an array sensor, such as array sensor 19, having a grid 17 of sensor elements.

[0117] The system further comprises a controller and a plurality of controllable nozzles as fire fighting devices 3a-3e, which are mounted on at least one of the wall 103 and ceiling 105 of the room 101. Each of the fire fighting devices 3a-3e is arranged to selectively release or stop a supply of fire extinguishing fluid to one of the plurality of zones 210a-210e, 310a-310h upon activation by the controller 9.

[0118] The method 400 comprises operating the controller 9 to carry out the following steps:

[0119] A step 410 of associating each of the sensor elements of the array sensor 19 to at least one zone 210a-210e, 310a-310h of the room 101, the at least one zone 210a-210e, 310a-310h being one of a plurality of zones 210a-210e, 310a-310h, each of the plurality of zones 210a-210e, 310a-310h comprising at least one of floor surface and wall surface of the room 101.

[0120] A step 420 of determining the presence of a fire F in at least one of the zones 210a-210e, 310a-310h responsive to a signal from the array sensor 19. Accordingly, the location of the fire F is determined in this step.

[0121] A step 430 of identifying a fire fighting area 220 in the at least one of the zones 210a-210e, 310a-310h in which the fire F is present. Based on the location of the fire F, which was determined in step 420, the fire fighting area 220 is thus identified.

[0122] A step 440 of controlling the plurality of fire fighting devices 3a-3e to provide fire extinguishing fluid to the fire fighting area 220 such that any square meter (m.sup.2) of floor surface in the fire fighting area 220 is provided with at least 0.4 (l/m.sup.2)/min of fire extinguishing fluid corresponding to at least 0.1 gpm/sqf. Preferably, before controlling the fire fighting devices 3a-3e to provide the fire extinguishing fluid, a fire detector, such as a smoke detector, is required to detect the presence of the fire-condition. Expressed differently, the fire detector detecting the fire is the requirement for the activation of any of the fire fighting devices 3a-3e.

[0123] The present disclosure thus relates to a system 1 and a corresponding method 400 for fire fighting of a room 101 comprising one or more fire locator devices 7 comprising an array sensor 19 having a grid 17 of sensor elements each; a controller 9 that associates each of the sensor elements of the array sensor 19 to at least one zone 210a-210e, 310a-310h; a plurality of controllable fire fighting devices 3a-3e being arranged to selectively release a supply of fire extinguishing fluid to one of the plurality of zones 210a-210e, 310a-310h upon activation by the controller 9.

LIST OF REFERENCE SIGNS

[0124] 1 system

[0125] 3a,b,c,d,e fire fighting device

[0126] 5a,b fire detection device

[0127] 7 fire locator device

[0128] 9 controller

[0129] 11a,b zone

[0130] 13 projection of pixel grid

[0131] 15 array

[0132] 17 pixel grid

[0133] 19 array sensor

[0134] 100 building

[0135] 101 room

[0136] 103 side wall

[0137] 105 ceiling

[0138] 106 floor

[0139] 107 heat source

[0140] 109 stationary hot spot

[0141] 210a-e zone

[0142] 212a-l overlapping region

[0143] 220 fire fighting area

[0144] 310a-h zone

[0145] 400 method for fire fighting

[0146] 410 associating step

[0147] 420 determination step

[0148] 430 identifying step

[0149] 440 control step

[0150] m, n grid parameters

[0151] F fire

[0152] NF fire-unrelated heat source

[0153] T.sub.1, T.sub.2 threshold

[0154] α.sub.1, α.sub.2, α.sub.3 angle, field of view