IP Library › Granted Patent US 12,260,740
Granted Patent B2
US 12,260,740 · App. 18/241,282 · Granted Mar 25, 2025

Self-testing fire sensing device

Inventors: Christopher Dearden (Melton Mowbray, GB); Michael Barson (Nuneaton, GB); Benjamin Wolf (Leicester, GB)
Assignee: Honeywell International Inc.
G08B29/145G08B17/107G08B17/117
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Quick Facts
Patent No.
US 12,260,740
App. No.
18/241,282
Granted
Mar 25, 2025
Kind
B2
Abstract

Devices, methods, and systems for a self-testing fire sensing device are described herein. One device includes an adjustable particle generator and a variable airflow generator configured to generate an aerosol density level sufficient to trigger a fire response without saturating an optical scatter chamber and the optical scatter chamber configured to measure a rate at which the aerosol density level decreases after the aerosol density level has been generated, determine an airflow rate from an external environment through the optical scatter chamber based on the measured rate at which the aerosol density level decreases, and determine whether the self-testing fire sensing device is functioning properly based on the fire response and the determined airflow rate.

Claims (38)

1. A self-testing fire sensing device, comprising:

a heat source configured to generate heat at a temperature sufficient to trigger a fire response;

a heat sensor configured to measure a rate of reduction in a temperature in the self-testing fire sensing device; and

a microcontroller comprising a memory and a processor configured to:

determine an airflow rate in the self-testing fire sensing device based on the measured rate of reduction in the temperature; and

determine whether the self-testing fire sensing device is functioning properly based on the determined airflow rate.

2. The device of claim 1 , wherein the microcontroller is configured to determine whether the self-testing fire sensing device is functioning properly based on the determined airflow rate and the fire response.

3. The device of claim 1 , wherein the microcontroller is configured to determine the self-testing fire sensing device is functioning properly responsive to the determined airflow rate exceeding a threshold airflow rate.

4. The device of claim 3 , wherein the microcontroller is configured to determine the self-testing fire sensing device is not functioning properly responsive to the determined airflow rate failing to exceed the threshold airflow rate.

5. The device of claim 4 , wherein the microcontroller is configured to transmit a fault notification to a monitoring device upon determining the self-testing fire sensing device is not functioning properly.

6. The device of claim 1 , wherein the memory is configured to store a threshold temperature sufficient to trigger the fire response from a properly functioning heat sensing element.

7. The device of claim 1 , wherein the memory is configured to store a period of time that has passed since heat was previously generated by the heat source.

8. The device of claim 7 , wherein the microcontroller is configured to send a command to the heat source to generate heat responsive to the period of time that has passed since heat was previously generated by the heat source.

9. The device of claim 1 , wherein the memory is configured to store the measured rate of reduction in temperature.

10. The device of claim 1 , wherein the memory is configured to store the determined airflow rate.

11. A method for a self-testing fire sensing device, comprising:

generating heat using a heat source;

measuring a rate of reduction in a temperature in the self-testing fire sensing device using a heat sensor;

determining an airflow rate in the self-testing fire sensing device based on the measured rate of reduction in the temperature; and

determining whether the self-testing fire sensing device is functioning properly based on the determined airflow rate.

12. The method of claim 11 , wherein the method includes:

receiving a command at the self-testing fire sensing device; and

generating the heat responsive to the command.

13. The method of claim 11 , wherein the method includes detecting a rise in temperature using the heat sensor.

14. The method of claim 11 , wherein the method includes drawing the heat past the heat sensor using a variable airflow generator.

15. The method of claim 14 , wherein the method includes turning off the heat source.

16. The method of claim 15 , wherein the method includes turning off the variable airflow generator.

17. A fire alarm system, comprising:

a self-testing fire sensing device configured to:

generate heat using a heat source;

measure a rate of reduction in a temperature in the self-testing fire sensing device using a heat sensor; and

determine an airflow rate in the self-testing fire sensing device based on the measured rate of reduction in the temperature; and

a monitoring device, including a microcontroller comprising a memory and a processor, configured to:

receive the determined airflow rate; and

determine the self-testing fire sensing device is functioning properly responsive to the airflow rate exceeding a threshold airflow rate.

18. The system of claim 17 , wherein the self-testing fire sensing device is configured to generate heat at a temperature sufficient to trigger a fire response.

19. The system of claim 18 , wherein the monitoring device is configured to determine the self-testing fire sensing device is functioning properly responsive to the heat triggering the fire response.

20. The system of claim 17 , wherein the self-testing fire sensing device is configured to generate heat using the heat source responsive to receiving a command from the monitoring device.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 1, 2023
From: DEARDEN, CHRISTOPHER; BARSON, MICHAEL; WOLF, BENJAMIN
To: HONEYWELL INTERNATIONAL INC.
Reel/Frame 064771/0053 →
Continuity (3)
Division 17184056 · Feb 24, 2021
Continuation 16552301 · Aug 27, 2019
Related Publication 20240038054A1 · Feb 1, 2024
References Cited (59)
US 3343044A · King, Jr. et al. · 1967 [cited by applicant]
US 4531114A · Topol · 1985 [cited by examiner]
US 4827244A · Bellavia · 1989 [cited by examiner]
US 5450066A · Brighenti · 1995 [cited by examiner]
US 5611620A · Wantz · 1997 [cited by examiner]
US 5617079A · Harrison · 1997 [cited by examiner]
US 5670946A · Ellwood · 1997 [cited by examiner]
US 5923260A · Endo et al. · 1999 [cited by applicant]
US 5936533A · Bernal et al. · 1999 [cited by applicant]
US 6015230A · Wantz · 2000 [cited by examiner]
US 6225910B1 · Kadwell · 2001 [cited by examiner]
US 7934411B2 · Koch · 2011 [cited by examiner]
US 8205478B1 · Hallisey · 2012 [cited by examiner]
US 8353625B1 · Feiter · 2013 [cited by examiner]
US 8766807B2 · Gonzales · 2014 [cited by applicant]
US 8933811B2 · Højmose · 2015 [cited by applicant]
US 9659485B2 · Piccolo, III · 2017 [cited by examiner]
US 9959748B2 · Moffa · 2018 [cited by applicant]
US 10783771B2 · Penney · 2020 [cited by examiner]
US 11132891B2 · Dearden et al. · 2021 [cited by applicant]
US 11227473B1 · Griffith et al. · 2022 [cited by applicant]
US 20020134131A1 · Pepper · 2002 [cited by examiner]
US 20040035179A1 · Koch · 2004 [cited by examiner]
US 20050212678A1 · Berg · 2005 [cited by examiner]
US 20070194907A1 · Tawil · 2007 [cited by examiner]
US 20080018485A1 · Kadwell · 2008 [cited by examiner]
US 20090078065A1 · Rossiter · 2009 [cited by examiner]
US 20090308134A1 · Pepper · 2009 [cited by examiner]
US 20100018723A1 · Bleil et al. · 2010 [cited by applicant]
US 20140168647A1 · Ju · 2014 [cited by examiner]
US 20150302727A1 · Piccolo, III · 2015 [cited by examiner]
US 20150310732A1 · Piccolo, III · 2015 [cited by examiner]
US 20160240059A1 · Stowell · 2016 [cited by examiner]
US 20170124829A1 · Tennies · 2017 [cited by examiner]
US 20170287318A1 · Moffa · 2017 [cited by examiner]
US 20180075733A1 · Brown · 2018 [cited by examiner]
US 20180293878A1 · Penney · 2018 [cited by examiner]
US 20190291866A1 · Jegodtka · 2019 [cited by examiner]
US 20200250963A1 · Rodriguez · 2020 [cited by applicant]
US 20200319154A1 · Dohi · 2020 [cited by examiner]
US 20200320857A1 · Lang · 2020 [cited by examiner]
US 20210046346A1 · Fujiwara · 2021 [cited by examiner]
CA 1119269A · 1982 [cited by applicant]
CN 101537236A · 2009 [cited by applicant]
CN 101763708A · 2010 [cited by applicant]
CN 102054322A · 2011 [cited by applicant]
DE 1291140B · 1969 [cited by applicant]
DE 20215640U1 · 2003 [cited by applicant]
DE 102012215212A1 · 2014 [cited by applicant]
EP 2320397A1 · 2011 [cited by applicant]
GB 2176600A · 1986 [cited by applicant]
GB 2459322A · 2009 [cited by applicant]
WO 0227293A2 · 2002 [cited by applicant]
WO 2017060716A1 · 2017 [cited by applicant]
WO 2017216539A1 · 2017 [cited by applicant]
WO 2018193086A1 · 2018 [cited by applicant]
Extended Search Report from related EP Application No. 20189064.7, dated Feb. 11, 2021 (11 pages). [cited by applicant]
First Chinese Office Action & Search Report from related Chinese Application No. 202010713357.X, dated Oct. 28, 2021 (Original Document 7 pgs; Translated Copy 10 pgs—17 pgs total). [cited by applicant]
Second Chinese Office Action for related Chinese Application No. 202010713357.X, dated May 20, 2022 (Original Document 5 pgs; Translated Copy 8 pgs—13 pgs total). [cited by applicant]