IP Library Granted Patent US 12,567,321
Granted Patent B2
US 12,567,321 · App. 17/674,318 · Granted Mar 3, 2026

Testing a heat detector of a self-testing hazard sensing device

Inventors: Benjamin H. Wolf (Leicester, GB); Christopher Dearden (Melton Mowbray, GB); Michael Barson (Nuneaton, GB)
Assignee: Honeywell International Inc.
G08B29/145G01K7/22G01K15/007
View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 12,567,321
App. No.
17/674,318
Granted
Mar 3, 2026
Kind
B2
Abstract

Devices, methods, and systems for testing a heat detector of a self-testing hazard sensing device are described herein. One device includes a heat detector, and a controller configured to provide energy to the heat detector to heat the heat detector to a threshold temperature, determine an amount of time it takes for the heat detector to heat to the threshold temperature, determine whether the amount of time it takes for the heat detector to heat to the threshold temperature meets or exceeds a threshold amount of time, and determine whether the heat detector is functioning properly based on whether the amount of time it takes for the heat detector to heat to the threshold temperature meets or exceeds the threshold amount of time.

Claims (38)

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

a heat detector; and

a controller having a memory and processor to:

provide energy to the heat detector using a current source that is external to the self-testing hazard sensing device to heat the heat detector to a threshold temperature, wherein the current source that is external to the self-testing hazard sensing device is wiring of a facility in which the self-testing hazard sensing device is installed;

determine an amount of time it takes for the heat detector to heat to the threshold temperature;

determine whether the amount of time it takes for the heat detector to heat to the threshold temperature meets or exceeds a threshold amount of time;

determine, after the heat detector has heated to the threshold temperature, an amount of time it takes for the heat detector to cool from the threshold temperature to an additional threshold temperature;

determine whether the amount of time it takes for the heat detector to cool from the threshold temperature to the additional threshold temperature meets or exceeds an additional threshold amount of time;

determine whether the heat detector is functioning properly based on whether the amount of time it takes for the heat detector to heat to the threshold temperature meets or exceeds the threshold amount of time and whether the amount of time it takes for the heat detector to cool from the threshold temperature to the additional threshold temperature meets or exceeds the additional threshold amount of time; and

determine whether air flow through the self-testing hazard sensing device is functioning properly based on whether the amount of time it takes for the heat detector to heat to the threshold temperature meets or exceeds the threshold amount of time and whether the amount of time it takes for the heat detector to cool from the threshold temperature to the additional threshold temperature meets or exceeds the additional threshold amount of time.

2 . The self-testing hazard sensing device of claim 1 , wherein the heat detector comprises a thermistor.

3 . The self-testing hazard sensing device of claim 1 , wherein the threshold amount of time is a baseline amount of time it takes for the heat detector to heat to the threshold temperature while the energy is provided to the heat detector.

4 . The self-testing hazard sensing device of claim 1 , wherein the memory and processor of the controller is to provide a notification upon determining the heat detector is not functioning properly.

5 . The self-testing hazard sensing device of claim 4 , wherein the memory and processor of the controller is to provide the notification by illuminating a light of the self-testing hazard sensing device.

6 . The self-testing hazard sensing device of claim 4 , wherein the memory and processor of the controller is to provide the notification by transmitting the notification to an additional device.

7 . A method of operating a self-testing hazard sensing device, comprising:

providing, by a controller having a memory and processor, energy to a heat detector of the self-testing hazard sensing device using a current source that is external to the self-testing hazard sensing device to heat the heat detector to a threshold temperature, wherein the current source that is external to the self-testing hazard sensing device is wiring of a facility in which the self-testing hazard sensing device is installed;

determining, by the controller, an amount of time it takes for the heat detector to heat to the threshold temperature;

determining, by the controller whether the amount of time it takes for the heat detector to heat to the threshold temperature meets or exceeds a threshold amount of time;

determining, by the controller after the heat detector has heated to the threshold temperature, an amount of time it takes for the heat detector to cool from the threshold temperature to an additional threshold temperature;

determining, by the controller, whether the amount of time it takes for the heat detector to cool from the threshold temperature to the additional threshold temperature meets or exceeds an additional threshold amount of time;

determining, by the controller, whether the heat detector is functioning properly based on whether the amount of time it takes for the heat detector to heat to the threshold temperature meets or exceeds the threshold amount of time and whether the amount of time it takes for the heat detector to cool from the threshold temperature to the additional threshold temperature meets or exceeds the additional threshold amount of time; and

determining, by the controller, whether air flow through the self-testing hazard sensing device is functioning properly based on whether the amount of time it takes for the heat detector to heat to the threshold temperature meets or exceeds the threshold amount of time and whether the amount of time it takes for the heat detector to cool from the threshold temperature to the additional threshold temperature meets or exceeds the additional threshold amount of time.

8 . The method of claim 7 , wherein the method includes determining the heat detector is functioning properly upon determining the amount of time it takes for the heat detector to heat to the threshold temperature does not meet or exceed the threshold amount of time.

9 . The method of claim 7 , wherein the method includes determining the heat detector is not functioning properly upon determining the amount of time it takes for the heat detector to heat to the threshold temperature meets or exceeds the threshold amount of time.

10 . The method of claim 7 , wherein the method includes determining whether the amount of time it takes for the heat detector to heat to the threshold temperature meets or exceeds the threshold amount of time by comparing the amount of time it takes for the heat detector to heat to the threshold temperature to the threshold amount of time.

11 . The method of claim 7 , wherein the method includes determining whether to replace the heat detector based on whether the amount of time it takes for the heat detector to heat to the threshold temperature meets or exceeds the threshold amount of time.

12 . A self-testing hazard sensing device, comprising:

a heat detector; and

a controller having a memory and processor to:

provide energy to the heat detector using a current source that is external to the self-testing hazard sensing device to heat the heat detector to a first threshold temperature, wherein the current source that is external to the self-testing hazard sensing device is wiring of a facility in which the self-testing hazard sensing device is installed;

determine, after the heat detector has heated to the first threshold temperature, an amount of time it takes for the heat detector to cool from the first threshold temperature to a second threshold temperature;

determine whether the amount of time it takes for the heat detector to cool to the second threshold temperature meets or exceeds a threshold amount of time;

determine whether the heat detector is functioning properly based on whether the amount of time it takes for the heat detector to cool to the second threshold temperature meets or exceeds the threshold amount of time; and

determine whether air flow through the self-testing hazard sensing device is functioning properly based on whether the amount of time it takes for the heat detector to cool to the second threshold temperature meets or exceeds the threshold amount of time.

13 . The self-testing hazard sensing device of claim 12 , wherein the memory and processor of the controller is to determine the heat detector is functioning properly upon determining the amount of time it takes for the heat detector to cool to the second threshold temperature does not meet or exceed the threshold amount of time.

14 . The self-testing hazard sensing device of claim 12 , wherein the memory and processor of the controller is to determine the heat detector is not functioning properly upon determining the amount of time it takes for the heat detector to cool to the second threshold temperature meets or exceeds the threshold amount of time.

15 . The self-testing hazard sensing device of claim 12 , wherein the threshold amount of time is a baseline amount of time it takes for the heat detector to cool from the first threshold temperature to the second threshold temperature after the heat detector has heated to the first threshold temperature.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 17, 2022
From: WOLF, BENJAMIN H.; DEARDEN, CHRISTOPHER; BARSON, MICHAEL
To: HONEYWELL INTERNATIONAL INC.
Reel/Frame 059036/0206 →
Continuity (1)
Related Publication 20230260390A1 · Aug 17, 2023
References Cited (19)
US 5644071A · Wagner · 1997 [cited by applicant]
US 6161958A · Rattman · 2000 [cited by examiner]
US 6288638B1 · Tanguay · 2001 [cited by examiner]
US 6508584B2 · Blankenagel · 2003 [cited by applicant]
US 11024154B1 · Lang et al. · 2021 [cited by applicant]
US 11127284B1 · Barson et al. · 2021 [cited by applicant]
US 11132891B2 · Dearden et al. · 2021 [cited by applicant]
US 11151851B1 · Moix Olive · 2021 [cited by examiner]
US 11227473B1 · Griffith et al. · 2022 [cited by applicant]
US 20200402380A1 · Barson · 2020 [cited by examiner]
US 20210182236A1 · Moseman · 2021 [cited by examiner]
US 20210347106A1 · Morris · 2021 [cited by examiner]
US 20220058929A1 · Dearden et al. · 2022 [cited by applicant]
US 20240264007A1 · Bambila · 2024 [cited by examiner]
CN 105823576A · 2016 [cited by applicant]
CN 106530578A · 2017 [cited by examiner]
EP 2593762B1 · 2016 [cited by applicant]
EP 2665993B1 · 2019 [cited by applicant]
KR 101823543B1 · 2018 [cited by applicant]