Method and device for identifying and localizing a fire

• US 20070008157A1
• Filed: 08/24/2004
• Published: 01/11/2007
• Est. Priority Date: 08/24/2004
• Status: Active Grant

• Current Assignee: Wagner Group GmbH
• Original Assignee: Wagner Group GmbH
• Inventors: Siemens, Andreas, Reinecke, Claus-Peter
• Granted Patent: US 7,375,642 B2
• Time in Patent Office: Days
• US Class Current: 340/577
• CPC Class Codes: G08B 17/10 Actuation by presence of smoke or gases , e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means

Abstract

The invention relates to a method and a device for detecting and localizing sources of fire in one or more monitored areas (R₁, . . . , R_n) utilizing a suction pipe system (3) connecting the plurality of monitored areas (R₁, . . . , R_n) and which communicates with each individual monitored area (R₁, . . . , R_n) by means of at least one suction opening (4), a suction device (5) for extracting air samples (6) representative of the room air of the individual monitored areas (R₁, . . . , R_n) from the individual monitored areas (R₁, . . . , R_n) by means of the suction pipe system (3) and the suction openings (4), and a sensor (7) for detecting at least one fire parameter in the air samples (6) extracted through the suction pipe system (3), whereby the inventive device comprises a blowing device (8) for blowing out the air samples (6) suctioned into the suction pipe system (3) when sensor (7) detects at least one fire parameter in the extracted air samples (6). The fire is localized by means of the transit time measurement of a re-extracted fire parameter.

Claims

1. Method for detecting and localizing a fire and/or the origin of a fire in one or more monitored areas comprising the following process steps:

a) extracting air samples in each case representative of the room air of the respective individual monitored areas from said individual monitored areas through a common suction pipe system;

b) detecting at least one fire parameter in the air samples suctioned through suction pipe system with at least one sensor for detecting fire parameters;

c) blowing out the extracted air samples within suction pipe system * by means of a blower or suctioning/blower device;

d) re-extracting air samples from the individual monitored areas through suction pipe system at least until the at least one sensor re-detects a fire parameter in air samples;

e) evaluating the time elapsed before the re-detecting of the fire parameter in the re-extracted air samples from process step d) in order to localize a fire or the site of an imminent fire in one of the plurality of monitored areas; and

f) emitting a signal indicating the development and/or presence of a fire in one or more of monitored areas wherein the signal contains further information for a precise localization of the fire in said one or more monitored areas.

2. Method as claimed in claim 1, further comprising the following process steps subsequent to process step a):

a1) determining the flow rate to air samples in suction pipe system during the continuous extraction of respective air samples from individual monitored areas; and

a2) calculating the time necessary to fully blow out air samples located in suction pipe system.

3. Method as claimed in claim 1, wherein process step c) comprises the process step of determining the flow rate during said blowing out in order to calculate the time necessary to fully blow out the air samples located within suction pipe system.

4. Method as claimed in claim 1, further comprising the following process steps subsequent to process step d):

d1) determining the flow rate to air samples in suction pipe system during the renewed extraction of respective air samples from individual monitored areas; and

d2) calculating the transit time of respective air samples representative of the room air of the individual monitored areas during the renewed extraction of respective air samples from individual monitored areas.

5. Method as claimed in claim 1, wherein the air sampling performed in process steps a) and d) is realized by means of a suction device, wherein the subsequent re-extraction of air samples performed in process step d) ensues with a suction line which is reduced in comparison to the suction line used in process step a).

6. Method as claimed in claim 1 further including an auto-adjusting procedure comprising the following process steps:

i) artificially producing a fire parameter at suction opening at the most distant monitored area from the at least one sensor over the entire time of the auto-adjusting procedure;

ii) suctioning air samples from individual monitored areas through common suction pipe system until the at least one sensor detects the artificially-generated fire parameter in extracted air samples;

iii) blowing out extracted air samples located in suction pipe system by means of a blowing or suctioning/blowing device;

iv) renewed extraction of air samples from individual monitored areas through suction pipe system at least until sensor redetects an artificially-generated fire parameter in air samples;

v) evaluating the transit time elapsed until the re-detection of the artificially-generated fire parameter in the re-extracted air samples performed in process step iv) in order to determine the maximum transit time for the suction pipe system;

vi) calculating the transit times for respective air samples representative of the room air of individual monitored areas from individual monitored areas based on the maximum transit times determined in process step v) and the configuration of suction pipe system, in particular the distance between suction openings, the diameter to the suction pipe system and the diameter to suction openings; and

vii) storing the calculated transit times for respective air samples in a table.

7. Method claim 6, wherein the auto-adjusting procedure according to process step vii) further comprises the following process step:

viii) utilizing a correcting function on the calculated transit times stored in the table in order to update the transit time values occurring for the individual monitored areas.

8. Method as claimed in claim 6, wherein the analysis of the transit time occurring in the event of a fire is made by comparing the occurring transit time with the respectively calculated transit times saved to the table in the auto-adjusting procedure.

9. Method as claimed in claim 1, wherein the analysis of the transit time occurring is made by comparing the occurring transit time with the respective transit times calculated theoretically for individual monitored areas in dependence on at least one of the following parameters:

the length of the respective sections of the suction pipe system between the at least one sensor and the suction openings of the respectively monitored areas disposed in suction pipe system;

the effective flow cross-section of suction pipe system and/or the respective sections of suction pipe system between the at least one sensor e and the respective monitored areas; and

the flow rate of the air samples in suction pipe system and/or in the respective sections of suction pipe system between the at least one sensor e and the suction openings of the respective monitored areas.

10. Fire detection device for detecting and localizing a fire and/or the origin of a fire in one or more monitored areas comprising a suction pipe system connecting said monitored areas which communicates with each individual monitored area by means of at least one suction opening, a suction device for extracting representative air samples (from individual monitored areas by means of suction pipe system and suction openings, and at least one sensor for detecting at least one fire parameter in the air samples suctioned through suction pipe system, characterized by a blowing device blowing out the air samples sucked into suction pipe system when the at least one sensor detects at least one fire parameter in said extracted air samples, and by at least one indicator element which identifies the site of a fire in one of monitored areas and/or by a communication device which transmits information on the development and/or presence of a fire in one or more of said monitored areas and on the precise location of the fire in said one or more monitored areas to a location remote of the device.

11. Device as claimed in claim 10, further comprising a controller for a time-coordinated controlling of suction device and blowing device in agreement with a signal emitted by the at least one sensor g when said at least one sensor detects at least one fire parameter in air samples.

12. Device as claimed in claim 10, further comprising a memory means for storing the transit time values.

13. Device as claimed in claim 10, further comprising at least one smoke generator arranged near a suction opening and artificially generating a fire parameter for setting and testing the fire detection device.

14. Device as claimed in claim 10, further comprising at least one sensor for measuring the flow rate of air samples in the suction pipe system.

15. Device as claimed in claim 10, further comprising a processor for evaluating a signal emitted by sensor ( when said at least one sensor ( detects a fire parameter in an air sample ( and a control signal emitted by controller to suction device and/or blowing device.

16. Device as claimed in claim 10, wherein the diameters and/or the cross-sectional shape to individual suction openings is configured contingent upon respective monitored areas.

17. Device as claimed in claim 10, wherein the diameters and/or the cross-sectional shape to the individual sections of suction pipe system between the at least one sensor and the respective monitored areas is configured contingent upon the respective monitored areas.

18. Device as claimed in claim 10, wherein the suction device and the blowing device are configured together as one blower which changes the direction it conveys air in response to a control signal from controller.

19. Device as claimed in claim 18, wherein the blower is a reversing-rotation fan.

20. Device as claimed in claim 18, that wherein the blower is a fan having ventilation flaps.

21. Application of the device as claimed in claim 10 as a fire detection component of a fire extinguishing system for activating the introduction of a fire extinguishing agent in one of monitored areas.