CA2501140A1 - Method and apparatus for indicating activation of a smoke detector alarm - Google Patents

Method and apparatus for indicating activation of a smoke detector alarm

Info

Publication number
CA2501140A1
CA2501140A1 CA 2501140 CA2501140A CA2501140A1 CA 2501140 A1 CA2501140 A1 CA 2501140A1 CA 2501140 CA2501140 CA 2501140 CA 2501140 A CA2501140 A CA 2501140A CA 2501140 A1 CA2501140 A1 CA 2501140A1
Authority
CA
Grant status
Application
Patent type
Prior art keywords
alarm
device
parameter
audible
smoke
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CA 2501140
Other languages
French (fr)
Other versions
CA2501140C (en )
Inventor
Richard J. Roby
Michael S. Klassen
Christopher F. Schemel
Diwakar Vashishat
Maclain M. Holton
Kelly R. Flint
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Combustion Science and Engineering Inc
Original Assignee
Combustion Science & Engineering, Inc.
Richard J. Roby
Michael S. Klassen
Christopher F. Schemel
Diwakar Vashishat
Maclain M. Holton
Kelly R. Flint
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date

Links

Classifications

    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B29/00Checking or monitoring of signalling or alarm systems; Prevention or correction of operating errors, e.g. preventing unauthorised operation
    • G08B29/18Prevention or correction of operating errors
    • G08B29/185Signal analysis techniques for reducing or preventing false alarms or for enhancing the reliability of the system
    • G08B29/188Data fusion; cooperative systems, e.g. voting among different detectors
    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B1/00Systems for signalling characterised solely by the form of transmission of the signal
    • G08B1/08Systems for signalling characterised solely by the form of transmission of the signal using electric transmission ; transformation of alarm signals to electrical signals from a different medium, e.g. transmission of an electric alarm signal upon detection of an audible alarm signal
    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B17/00Fire alarms; Alarms responsive to explosion
    • G08B17/10Actuation by presence of smoke or gases automatic alarm devices for analysing flowing fluid materials by the use of optical means
    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B3/00Audible signalling systems; Audible personal calling systems
    • G08B3/10Audible signalling systems; Audible personal calling systems using electric transmission; using electromagnetic transmission
    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B6/00Tactile signalling systems, e.g. personal calling systems
    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B7/00Signalling systems according to more than one of groups G08B3/00-G08B6/00; Personal calling systems according to more than one of groups G08B3/00-G08B6/00
    • G08B7/06Signalling systems according to more than one of groups G08B3/00-G08B6/00; Personal calling systems according to more than one of groups G08B3/00-G08B6/00 using electric transmission, e.g. involving audible and visible signalling through the use of sound and light sources
    • GPHYSICS
    • G09EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09BEDUCATIONAL OR DEMONSTRATION APPLIANCES; APPLIANCES FOR TEACHING, OR COMMUNICATING WITH, THE BLIND, DEAF OR MUTE; MODELS; PLANETARIA; GLOBES; MAPS; DIAGRAMS
    • G09B19/00Teaching not covered by other main groups of this subclass
    • GPHYSICS
    • G09EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09BEDUCATIONAL OR DEMONSTRATION APPLIANCES; APPLIANCES FOR TEACHING, OR COMMUNICATING WITH, THE BLIND, DEAF OR MUTE; MODELS; PLANETARIA; GLOBES; MAPS; DIAGRAMS
    • G09B21/00Teaching, or communicating with, the blind, deaf or mute
    • G09B21/009Teaching or communicating with deaf persons

Abstract

A method for detecting smoke detector alarms comprises analyzing at least two parameters of ambient sound over a period of time to detect a temporal pattern of the alarm. In one embodiment, a series of samples are taken over a period of time sufficiently long to include at least one full period of a repeating sound pattern, and the two parameters are frequency and amplitude of the loudest sound in each sample. The algorithmic analysis may be triggered by a detection algorithm that utilizes a lower amount of power than the algorithmic analysis. In other embodiments, the detection apparatus is incorporated into a conventional smoke detector (800) that will detect both smoke and an alarm from another detector. In another embodiment, a smoke detector (800) includes a transceiver (880) to transmit an activation signal to neighboring smoke detectors (890) when a fire is detected and to receive an activation signal from neighboring detectors (890).

Claims (34)

1. A method for detecting a smoke detector audible alarm comprising the steps of:
examining a first parameter of ambient sound for a period of time;
examining a second parameter of the ambient sound for the period of time;
comparing the first parameter and the second parameter to an expected pattern; and declaring an audible alarm detection if both the first parameter and the second parameter match an expected pattern of the audible alarm.
2. The method of Claim 1, wherein the pattern varies temporally.
3. The method of Claim 1, wherein the ambient sound is sampled for a number of sample periods within the period of time.
4. The method of Claim 3, wherein the first parameter is a frequency of a peak amplitude in each of the sample periods.
5. The method of Claim 3, wherein the second parameter is a magnitude of a peak amplitude in each of the sample periods.
6. The method of Claim 3, further comprising the step of correlating the first parameter to the second parameter.
7. The method of Claim 6, wherein the correlating step is performed by determining when both the first parameter and the second parameter are at a value corresponding to an on portion of an audible alarm.
8. The method of Claim 7, wherein determining that the second parameter is at a value corresponding to an on portion of an audible alarm comprises the steps of determining a maximum peak amplitude from among the magnitudes of the peak amplitudes in each of the sample periods;
determining an amplitude threshold based on the maximum peak amplitude; and comparing each peak amplitude from each of the sample periods to the amplitude threshold.
9. The method of Claim 8, wherein the maximum peak amplitude is no less than a minimum amplitude above an average ambient noise level.
10. The method of Claim 1, further comprising the steps of examining a single parameter of ambient noise to determine if there is a possibility that an audible alarm may be present; and in the absence of a possibility that an audible alarm may be present, delaying a period of time and repeating the examining step;
wherein the steps of examining the first parameter and examining the second parameter are only performed if there is a possibility that an audible alarm may be present.
11. The method of Claim 1, further comprising the step of activating a tactile warning device when an audible alarm is detected.
12. The method of Claim 1, further comprising the step of sending an activation message to a remote device.
13. The method of Claim 12, wherein the remote device is a smoke detector configured to receive an activation message.
14. The method of Claim 12, wherein the remote device is a tactile alarm device.
15. The method of Claim 1, wherein the period of time corresponds to more than one full period of a temporally repeating period of the smoke detector audible alarm.
16. A device for detecting a smoke detector audible alarm comprising:
a microphone;
a processor connected to the microphone; and a tactile alarm device connected to the processor;
wherein the processor is configured to perform the steps of examining a first parameter of ambient sound for a period of time;

examining a second parameter of the ambient sound for the period of time;
comparing both the first parameter and the second parameter to an expected pattern; and declaring an audible alarm detection if both the first parameter and the second parameter match an expected pattern of the audible alarm.
17. The device of Claim 16, wherein the pattern varies temporally.
18. The device of Claim 16, wherein the ambient sound is sampled for a number of sample periods within the period of time.
19. The device of Claim 18, wherein the first parameter is a frequency of a peak amplitude in each of the sample periods.
20. The device of Claim 18, wherein the second parameter is a magnitude of a peak amplitude in each of the sample periods.
21. The device of Claim 18, wherein the processor is further configured to perform the step of correlating the first parameter to the second parameter.
22. The device of Claim 21, wherein the correlating step is performed by determining when both the first parameter and the second parameter are at a value corresponding to an on portion of an audible alarm.
23. The device of Claim 22, wherein the processor is configured to perform the step of determining that the second parameter is at a value corresponding to an on portion of an audible alarm by performing the steps of determining a maximum peak amplitude from among the magnitudes of the peak amplitudes in each of the sample periods;
determining an amplitude threshold based on the maximum peak amplitude; and comparing each peak amplitude from each of the sample periods to the amplitude threshold.
24. The device of Claim 23, wherein the maximum peak amplitude is no less than a minimum amplitude above an average ambient noise level.
25. The device of Claim 16, wherein the processor is further configured to perform the steps of examining a single parameter of ambient noise to determine if there is a possibility that an audible alarm may be present; and in the absence of a possibility that an audible alarm may be present, delaying a period of time and repeating the examining step;
wherein the steps of examining the first parameter and examining the second parameter are only performed if there is a possibility that an audible alarm may be present.
26. The device of Claim 16, further comprising a tactile warning device connected to the processor, the processor being further configured to activate the warning device when an audible alarm detection is declared.
27. The device of Claim 16, wherein the processor is further configured to perform the step of sending an activation message to a remote device via a transceiver connected to the processor.
28. The device of Claim 27, wherein the remote device is a smoke detector configured to receive an activation message.
29. The device of Claim 27, wherein the remote device is a tactile alarm device.
30. A smoke detector comprising:
a smoke detection circuit;
a microphone;
an alarm device;
a transmitter; and a processor connected to the microphone, the alarm device, and the transceiver, the processor being configured to perform the steps of receiving an indication from the smoke detection circuit that a fire has occurred;
analyzing ambient sound from the microphone to detect an audible alarm from another smoke detector; and activating the alarm device and transmitting an activation message to a remote alarm device upon receipt of either an indication that a fire has occurred from the smoke detection circuit or a detection of an audible alarm from another detector.
31. The smoke detector of Claim 30, wherein the remote alarm device is a tactile alarm.
32. The smoke detector of Claim 30, wherein the remote alarm device is a third device configured to activate an audible alarm upon receipt of the activation message.
33. The smoke detector of Claim 30, further comprising a receiver connected to the processor, wherein the receiver is further configured to perform the activating step upon receipt of an activation message via the receiver.
34. The smoke detector of Claim 30, wherein the alarm device is an audible alarm.
CA 2501140 2002-10-02 2003-10-02 Method and apparatus for indicating activation of a smoke detector alarm Active CA2501140C (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US41512702 true 2002-10-02 2002-10-02
US60/415,127 2002-10-02
PCT/US2003/031128 WO2004032078A3 (en) 2002-10-02 2003-10-02 Method and apparatus for indicating activation of a smoke detector alarm

Publications (2)

Publication Number Publication Date
CA2501140A1 true true CA2501140A1 (en) 2004-04-15
CA2501140C CA2501140C (en) 2010-04-13

Family

ID=32069814

Family Applications (1)

Application Number Title Priority Date Filing Date
CA 2501140 Active CA2501140C (en) 2002-10-02 2003-10-02 Method and apparatus for indicating activation of a smoke detector alarm

Country Status (8)

Country Link
US (1) US7015807B2 (en)
EP (1) EP1547041B1 (en)
JP (1) JP4279255B2 (en)
CA (1) CA2501140C (en)
DE (2) DE60315482T2 (en)
DK (1) DK1547041T3 (en)
ES (1) ES2291707T3 (en)
WO (1) WO2004032078A3 (en)

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Also Published As

Publication number Publication date Type
EP1547041A2 (en) 2005-06-29 application
DE60315482D1 (en) 2007-09-20 grant
EP1547041A4 (en) 2005-11-02 application
US7015807B2 (en) 2006-03-21 grant
ES2291707T3 (en) 2008-03-01 grant
WO2004032078A3 (en) 2004-08-12 application
JP2006502483A (en) 2006-01-19 application
DK1547041T3 (en) 2007-12-10 grant
US20040145467A1 (en) 2004-07-29 application
JP4279255B2 (en) 2009-06-17 grant
DE60315482T2 (en) 2008-04-30 grant
WO2004032078A2 (en) 2004-04-15 application
CA2501140C (en) 2010-04-13 grant
EP1547041B1 (en) 2007-08-08 grant

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