Fiber optic based smoke and/or overheat detection and monitoring for aircraft

Patent metadata

Field	Value
Publication number	US-11067457-B2
Application number	US-201715809474-A
Country	US
Kind code	B2
Filing date	Nov 10, 2017
Priority date	Nov 11, 2016
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

A method of monitoring smoke, fire, and temperature conditions includes transmitting light through a first fiber optic cable, the fiber optic cable terminating at a node disposed to monitor a smoke or fire condition at one or more predetermined areas, transmitting light along a second fiber optic cable, the second fiber optic cable arranged to monitor a temperature condition at one or more predetermined areas, receiving scattered light from the first fiber optic cable and/or the second fiber optic cable at a control system, and analyzing the scattered light to determine at least one of the presence and magnitude of smoke, fire and/or a temperature condition along the fiber harness or at the node.

First claim

What is claimed is:

1. A method of monitoring smoke, fire, and temperature conditions comprising:
transmitting light from a light source and through a first fiber optic cable of a fiber harness, the fiber optic cable terminating at a node disposed to monitor a smoke or fire condition at one or more predetermined areas, the first fiber cable branching off from the fiber harness at a fiber branch portion of the first fiber cable, the fiber branch portion terminating at the node;
transmitting light from the light source and along a second fiber optic cable of the fiber harness, the second fiber optic cable arranged to monitor a temperature condition at one or more predetermined areas;
receiving scattered light from the first fiber optic cable and the second fiber optic cable at a control system via a light sensitive device; and
analyzing the scattered light to determine at least one of the presence and magnitude of smoke, fire and/or a temperature condition along the fiber harness or at the node;
wherein the temperature condition at one or more fiber portions of the second fiber optic cable is determined by analyzing the scattered light that has been internally scattered in the second fiber optic cable at the one or more fiber portions and received at the light sensitive device.

2. The method according to claim 1 , wherein the light source is selectively operable to transmit the light signal.

3. The method according to claim 1 , further comprising selectably changing a wavelength of the transmitted light.

4. The method according to claim 1 , wherein the light sensitive device is associated with the node, the light sensitive device configured to receive the scattered light signal.

5. The method according to claim 1 , further comprising converting the scattered light signal into corresponding electrical signals for evaluation by a control unit.

6. A system for monitoring smoke, fire and/or temperature conditions within an aircraft structure comprising:
a fiber harness comprising a first fiber optic cable terminating at a node disposed to monitor a smoke or fire condition at one or more predetermined areas and a second fiber optic cable arranged to monitor a temperature condition at one or more predetermined areas, the first fiber cable branching off from the fiber harness at a fiber branch portion of the first fiber cable, the fiber branch portion terminating at the node; and
a control system operably connected to the fiber harness, the control system comprising:
one or more light sensitive devices configured to receive light from the first fiber optic cable and the second fiber optic cable; and
a control unit configured to:
analyze light received at the one or more light sensitive devices from the first fiber optic cable to determine one or more fire or smoke conditions at one or more predetermined areas; and
analyze light received at the one or more light sensitive devices from the second fiber optic cable to determine the temperature conditions at one or more predetermined areas;

wherein the temperature condition at the one or more predetermined areas is determined by analyzing the scattered light that has been internally scattered in the second fiber optic cable at one or more fiber portions of the second fiber optic cable disposed at the one or more predetermined areas and received at the light sensitive device.

7. The system according to claim 6 , wherein measuring the temperature further comprises determining an overheat condition.

8. The system according to claim 6 , wherein the one or more light sensitive devices comprises a first light sensitive device configured to receive light from the first fiber optic cable and a second light sensitive device configured to receive light from the second fiber optic cable.

9. The system according to claim 6 , wherein the control system includes a light source for transmitting the light signal along the first fiber optic cable and the second fiber optic cable.

10. The system according to claim 9 , wherein the control unit is operably coupled to the light source to selectively control emission of light from the light source.

11. The system according to claim 6 , wherein the light sensitive device is a photodiode.

12. The system according to claim 6 , wherein the light sensitive device converts the scattered light signal received at the control system into an electrical signal receivable by the control unit.

13. The system according to claim 6 , wherein the first fiber optic cable defines a plurality of nodes arranged within the aircraft structure.

14. The system according to claim 6 , wherein the aircraft structure is one or more of a cargo compartment, an avionics bay or other enclosed portion of the aircraft.

15. A method of monitoring a temperature condition comprising:
transmitting light along a fiber optic cable, the fiber optic cable arranged to monitor a temperature condition at one or more predetermined areas, the fiber optic cable including a plurality of branches, each branch of the plurality of branches terminating at a node, the light transmitted along the fiber optic cable and through the node;
receiving scattered light from the fiber optic cable;
communicating the scattered light to a light sensitive device; and
determining, via the control system, whether the scattered light indicates a presence of an undesirable temperature condition along the fiber harness and/or at the node;
wherein the temperature condition at one or more fiber portions of the fiber optic cable is determined by analyzing the scattered light that has been internally scattered in the fiber optic cable at the one or more fiber portions and received at the light sensitive device.

16. The method according to claim 15 , wherein the light source is selectively operable to transmit the light signal.

17. The method according to claim 15 , further comprising selectably changing a wavelength of the transmitted light.

Assignees

• Kidde Tech Inc

Inventors

• Birnkrant Michael J
• Coreth Stefan
• Bell Kenneth
• Alexander Jennifer M
• Harris Peter R
• Vincitore Antonio M

Classifications

• G01N33/0036

  specially adapted to detect a particular component (physical analysis of gaseous biological material G01N33/497) · CPC title

• G08B17/06

  Electric actuation of the alarm, e.g. using a thermally-operated switch · CPC title

• G08B17/107

  for detecting light-scattering due to smoke · CPC title

• G01K11/32 Primary

  using changes in transmittance, scattering or luminescence in optical fibres · CPC title