Fire detection system

• US 7,333,129 B2
• Filed: 07/01/2002
• Issued: 02/19/2008
• Est. Priority Date: 09/21/2001
• Status: Active Grant

• Current Assignee: Rosemount Aerospace, Inc. (Raytheon Technologies Corporation d/b/a RTX)
• Original Assignee: Rosemount Aerospace, Inc. (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Miller, Mark S., Wiegele, Thomas G.
• Primary Examiner(s): WONG, ALLEN C
• Application Number:
  US10/186,446
• Publication Number:
  US 20030058114A1
• Time in Patent Office: 2,059 Days
• Field of Search: 348/162, 348/154, 348/143, 340/522, 340/545.3, 340/506, 169/61
• US Class Current: 348/162
• CPC Class Codes: A62C 35/08 Containers destroyed or opened by bursting charge
• CPC Class Codes: A62C 37/40 with electric connection between sensor and actuator
• CPC Class Codes: A62C 99/0045 using solid substances, e.g. sand, ashes; using substances forming a crust
• CPC Class Codes: G08B 17/125 by using a video camera to detect fire or smoke
• CPC Class Codes: G08B 25/002 Generating a prealarm to the central station
• CPC Class Codes: G08B 29/183 Single detectors using dual technologies G08B13/1672, G08B13/2448, G08B13/2494 take precedence
• CPC Class Codes: G08B 29/188 Data fusion; cooperative systems, e.g. voting among different detectors
• CPC Class Codes: G08B 29/20 Calibration, including self-calibrating arrangements

Abstract

A fire detection system for an enclosed area comprises: at least one infrared (IR) imager for generating infrared images of at least a portion of the enclosed area, for determining from the images that a fire is perceived present in the enclosed area, and for generating a first signal indicative of the perceived presence of fire; at least one fire detector for monitoring at least a portion of the enclosed area, the fire detector comprising at least one fire byproduct chemical sensor for generating at least one second signal representative of the presence of at least one fire byproduct chemical in the enclosed area; and a controller governed by the first and second signals to confirm that a fire is present in the enclosed area. In one embodiment, the enclosed area is divided into a plurality of detection zones with at least one fire detector disposed at each detection zone. In this embodiment, the controller includes a first controller governed by the second signals for generating a third signal indicative of the presence of fire in the corresponding detection zone; and a second controller governed by the first and third signals to confirm that a fire is present in at least one detection zone of the enclosed area.

Claims

1. A fire detection system for an enclosed area, said system comprising

a plurality of infrared (IR) imagers oriented to view corresponding portions of the enclosed area, each IR imager of said plurality comprising:

an area array of IR radiation detectors for generating electrical signals of corresponding arrays of IR radiation measurements which are representative of infrared images of its corresponding portion of the enclosed area; and

an image processor for processing said electrical signals of said infrared images to determine if a fire is perceived present in said portion of the enclosed area, and for generating a first signal indicative of said perceived presence of fire;

at least one fire detector for monitoring at least a portion of the enclosed area, said fire detector comprising at least one fire byproduct chemical sensor for generating at least one second signal representative of the presence of at least one fire byproduct chemical in the enclosed area; and

a controller governed by said first signals generated by the plurality of IR imagers and said at least one second signal to confirm that a fire is present in the enclosed area.

2. The fire detection system of claim 1 wherein:

the enclosed area includes a plurality of detection zones; and

including at least one fire detector for each detection zone.

3. The fire detection system of claim 2 wherein the controller comprises:

a first controller for each fire detector, said first controller governed by the second signals of the sensors of the corresponding fire detector to generate a third signal indicative of the presence of fire in corresponding detection zone; and

a second controller coupled to the first controllers of the fire detectors and the plurality of IR imagers and governed by the first and third signals generated thereby to confirm that a fire is present in the enclosed area.

4. The fire detection system of claim 3 wherein the first and second controllers are operative independently of one another to confirm the presence of fire in the enclosed area.

5. The fire detection system of claim 3 including:

dual fire detectors for each detection zone;

wherein the fire detectors are coupled to the second controller over a dual loop bus.

6. The fire detection system of claim 1 wherein the first signals of the plurality of IR imagers are coupled to the controller over a dual loop bus.

7. The fire detection system of claim 1 wherein the sensors of the fire detector are disposed within a detection chamber.

8. The fire detection system of claim 1 wherein the at least one fire byproduct chemical sensor comprises a carbon monoxide sensor.

9. The fire detection system of claim 8 wherein the carbon monoxide sensor comprises a multi-layer micro-electromechanical system (MEMS) semiconductor structure.

10. The fire detection system of claim 9 wherein the MEMS carbon monoxide sensor comprises a tin oxide gas sensing layer.

11. The fire detection system of claim 10 wherein the MEMS carbon monoxide sensor comprises:

an aluminum substrate;

a ruthenium oxide heater layer; and

a glass layer disposed between the substrate layer and heater layer for thermal isolation;

wherein the tin oxide layer being disposed over the heater layer with an insulating layer disposed therebetween.

12. The fire detection system of claim 8 wherein the carbon monoxide sensor includes a built in test portion.

13. The fire detection system of claim 1 wherein the at least one fire byproduct chemical sensor comprises a hydrogen sensor.

14. The fire detection system of claim 13 wherein the hydrogen sensor comprises a multi-layer micro-electromechanical system (MEMS) semiconductor structure.

15. The fire detection system of claim 14 wherein the MEMS hydrogen sensor comprises a tin oxide gas sensing layer.

16. The fire detection system of claim 13 wherein the hydrogen sensor includes a built in test portion.

17. The fire detection system of claim 1 wherein the at least one fire byproduct chemical sensor includes both a carbon monoxide sensor and a hydrogen sensor.

18. The fire detection system of claim 1:

wherein the fire detector includes a smoke sensor for generating a fourth signal indicative of the presence of smoke in the enclosed area; and

wherein the controller is governed by the first, second and fourth signals to confirm that a fire is present in the enclosed area.

19. The fire detection system of claim 18 wherein the controller comprises:

a first controller for each fire detector, the first controller of the fire detector including the smoke sensor is governed by the second and fourth signals of the sensors of the corresponding fire detector to generate a third signal indicative of the presence of fire in the enclosed area; and

a second controller coupled to the first controllers of the fire detectors and the plurality of IR imagers and governed by the first and third signals generated thereby to confirm that a fire is present in the enclosed area.

20. The fire detection system of claim 18 wherein the smoke sensor includes a built in test portion.

21. The fire detection system of claim 1 wherein each IR imager includes a built in test portion.

22. The fire detection system of claim 1 wherein each fire detector includes a built in test portion.

23. A fire detection system for an enclosed area having a plurality of detection zones, said system comprising:

a plurality of infrared (IR) imagers, each IR imager comprising;

an area array of IR radiation detectors for generating electrical signals of corresponding arrays of IR radiation measurements which are representative of infrared images of a corresponding portion of the enclosed area; and

an image processor for processing said electrical signals of said infrared images to determine if a fire is perceived present in the corresponding portion, and for generating a first signal indicative of said perceived presence of fire;

at least one fire detector disposed at each detection zone, each fire detector for monitoring the corresponding detection zone of the enclosed area, each fire detector comprising at least one fire byproduct chemical sensor for generating at least one second signal representative of the presence of at least one fire byproduct chemical in the corresponding detection zone, and a first controller governed by the second signals for generating a third signal indicative of the presence of fire in the corresponding detection zone; and

a second controller governed by said first signals generated by the plurality of IR imagers and said third signals corresponding to the plurality of detection zones to confirm that a fire is present in at least one detection zone of the enclosed area.

24. The fire detection system of claim 23 wherein the first and second controllers are operative independently of each other to confirm the presence of fire in the enclosed area.

25. The fire detection system of claim 23 including dual fire detectors for each detection zone;

and wherein the fire detectors are coupled to the second controller over a dual loop bus.

26. The fire detection system of claim 25 including:

two IR imagers for the enclosed area;

wherein the IR imagers are coupled to the second controller over the dual loop bus.

27. The fire detection system of claim 26:

wherein the second controller includes third and fourth controllers;

wherein the dual loop bus is coupled to both the third and fourth controllers; and

wherein each of the third and fourth controllers is operative independent of the other to confirm that a fire is present in at least one detection zone of the enclosed area based on the signals of the dual loop bus coupled thereto.

28. The fire detection system of claim 23 wherein each IR imager includes means for producing a video signal representing the infrared images generated thereby;

and including a video display; and

a video selection switch coupled to the video signals and the video display and governed by the second controller to select a video signal for display on the video display.

29. The fire detection system of claim 28 wherein the second controller includes means for selecting a video signal for display on the video display based on the confirmation of fire in one of the portions of the enclosed area.

30. The fire detection system of claim 23 wherein the enclosed area comprises a cargo hold of an aircraft.

31. The fire detection system of claim 23:

wherein at least one fire detector includes a smoke sensor for generating a fourth signal indicative of the presence of smoke in the corresponding detection zone; and

wherein the first controller of each fire detector that includes the smoke sensor is governed by the second and fourth signals of the sensors of the corresponding fire detector to generate the third signal indicative of the presence of fire in the corresponding detection zone.

32. A fire detection system for a plurality of enclosed areas, each having a plurality of detection zones, said system comprising:

a plurality of infrared (IR) imagers for each enclosed area, each IR imager comprising;

an area array of IR radiation detectors for generating electrical signals of corresponding arrays of IR radiation measurements which are representative of infrared images of a corresponding portion of the corresponding enclosed area; and

an image processor for processing said electrical signals of said infrared images to determine if a fire is perceived present in the corresponding portion, and for generating a first signal indicative of said perceived presence of fire;

at least one fire detector disposed at each detection zone of each enclosed area, each fire detector for monitoring the corresponding detection zone of the corresponding enclosed area, each fire detector comprising at least one fire byproduct chemical sensor for generating at least one second signal representative of the presence of at least one fire byproduct chemical in the corresponding detection zone, and a first controller governed by the second signals for generating a third signal indicative of the presence of fire in the corresponding detection zone; and

a second controller governed by said first signals generated by the plurality of IR imagers of each enclosed area and said third signals corresponding to the plurality of detection zones of each enclosed area to confirm that a fire is present in at least one detection zone of at least one of the enclosed areas.

33. The fire detection system of claim 32 wherein the first and second controllers are operative independently of each other to confirm the presence of fire in at least one of the enclosed areas.

34. The fire detection system of claim 32 including:

dual fire detectors for each detection zone of each enclosed area;

wherein the fire detectors are coupled to the second controller over a dual loop bus.

35. The fire detection system of claim 34 including:

two IR imagers for each of the enclosed areas;

wherein the IR imagers are coupled to the second controller over the dual loop bus.

36. The fire detection system of claim 35:

wherein the second controller includes third and fourth controllers;

wherein the dual loop bus is coupled to both the third and fourth controllers; and

wherein each of the third and fourth controllers is operative independent of the other to confirm that a fire is present in at least one detection zone of at least one enclosed area based on the signals of the dual loop bus coupled thereto.

37. The fire detection system of claim 32 wherein each IR imager includes means for producing a video signal representing the infrared images generated thereby;

and including a video display; and

a video selection switch coupled to the video signals and the video display and governed by the second controller to select a video signal for display on the video display.

38. The fire detection system of claim 37 wherein the second controller includes means for selecting a video signal for display on the video display based on the confirmation of fire in one of the portions of the enclosed areas.

39. The fire detection system of claim 32 wherein the enclosed areas comprise cargo holds of an aircraft.

40. The fire detection system of claim 32:

wherein at least one fire detector includes a smoke sensor for generating a fourth signal indicative of the presence of smoke in the corresponding detection zone; and

wherein the first controller of each fire detector that includes the smoke sensor is governed by the second and fourth signals of the sensors of the corresponding fire detector to generate the third signal indicative of the presence of fire in the corresponding detection zone.

41. A fire detection system for an enclosed area, said system comprising:

a plurality of infrared (IR) imagers oriented to view corresponding portions of the enclosed area, each IR imager of said plurality comprising;

an area array of IR radiation detectors for generating electrical signals of corresponding arrays of IR radiation measurements which are representative of infrared images of its corresponding portion of the enclosed area; and

an image processor for processing said electrical signals of said infrared images to determine if a fire is perceived present in said portion of the enclosed area, and for generating a first signal indicative of said perceived presence of fire;

at least one fire detector for monitoring at least a portion of the enclosed area, said fire detector comprising a smoke sensor for generating a second signal indicative of the presence of smoke in the enclosed area, and at least one fire byproduct chemical sensor for generating at least one third signal representative of the presence of at least one fire byproduct chemical in the enclosed area; and

a controller governed by said first signals generated by the plurality of IR imagers, second signal, and at least one third signal to confirm that a fire is present in the enclosed area.

42. A fire detection system for an enclosed area having a plurality of detection zones, said system comprising:

a plurality of infrared (IR) imagers, each IR imager comprising;

an area array of IR radiation detectors for generating electrical signals of corresponding arrays of IR radiation measurements which are representative of infrared images of a corresponding portion of the enclosed area; and

an image processor for processing said electrical signals of said infrared images to determine if a fire is perceived present in the corresponding portion, and for generating a first signal indicative of said perceived presence of fire;

at least one fire detector disposed at each detection zone, each fire detector for monitoring the corresponding detection zone of the enclosed area, each fire detector comprising a smoke sensor for generating a second signal indicative of the presence of smoke in the corresponding detection zone, at least one fire byproduct chemical sensor for generating at least one third signal representative of the presence of at least one fire byproduct chemical in the corresponding detection zone, and a first controller governed by the second and third signals for generating a fourth signal indicative of the presence of fire in the corresponding detection zone; and

a second controller governed by said first signals generated by the plurality of IR imagers and said fourth signals corresponding to the plurality of detection zones to confirm that a fire is present in at least one detection zone of the enclosed area.

43. A fire detection system for a plurality of enclosed areas, each having a plurality of detection zones, said system comprising:

a plurality of infrared (IR) imagers for each enclosed area, each IR imager comprising;

an area array of IR radiation detectors for generating electrical signals of corresponding arrays of IR radiation measurements which are representative of infrared images of a corresponding portion of the corresponding enclosed area; and

an image processor for processing said electrical signals of said infrared images to determine if a fire is perceived present in the corresponding portion, and for generating a first signal indicative of said perceived presence of fire;

at least one fire detector disposed at each detection zone of each enclosed area, each fire detector for monitoring the corresponding detection zone of the corresponding enclosed area, each fire detector comprising a smoke sensor for generating a second signal indicative of the presence of smoke in the corresponding detection zone, at least one fire byproduct chemical sensor for generating at least one third signal representative of the presence of at least one fire byproduct chemical in the corresponding detection zone, and a first controller governed by the second and third signals for generating a fourth signal indicative of the presence of fire in the corresponding detection zone; and

a second controller governed by said first signals generated by the plurality of IR imagers of each enclosed area and said fourth signals corresponding to the plurality of detection zones of each enclosed area to confirm that a fire is present in at least one detection zone of at least one of the enclosed areas.