System and method to identify obscuration fault in a flame detector

Patent metadata

Field	Value
Publication number	US-2019019388-A1
Application number	US-201816033748-A
Country	US
Kind code	A1
Filing date	Jul 12, 2018
Priority date	Jul 12, 2017
Publication date	Jan 17, 2019
Grant date	—

Abstract

Embodiments relate generally to systems and methods for detecting obscuration of a window of a flame detector. A flame detector may comprise a housing; a window attached to the housing, wherein the window allows radiation to pass through to the interior of the housing; a transmitter configured to emit electromagnetic radiation; a receiver configured to receive electromagnetic radiation emitted by the transmitter; and a plurality of angled surfaces configured to direct the electromagnetic radiation from the transmitter through at least a portion of the window and toward the receiver.

First claim

What is claimed is:

1 . A flame detector comprising:
a housing; a window attached to the housing, wherein the window allows radiation to pass through to the interior of the housing; a transmitter configured to emit electromagnetic radiation; a receiver configured to receive electromagnetic radiation emitted by the transmitter; and a plurality of angled surfaces configured to direct the electromagnetic radiation from the transmitter through at least a portion of the window and toward the receiver.

2 . The flame detector of claim 1 , wherein the transmitter and the receiver are located below the plane of the window.

3 . The flame detector of claim 1 , wherein the plurality of angled surfaces comprises:
a first angled surface configured to direct the electromagnetic radiation from the transmitter into a plane at least parallel to the plane of the window; a second angled surface configured to direct the electromagnetic radiation within the plane at least parallel to the plane of the window; a third angled surface configured to direct the electromagnetic radiation within the plane at least parallel to the plane of the window; and a fourth angled surface configured to direct the electromagnetic radiation out of the plane at least parallel to the plane of the window toward the receiver.

4 . The flame detector of claim 1 , wherein the plurality of angled surfaces comprises at least two angled surfaces.

5 . The flame detector of claim 1 , wherein the plurality of angled surfaces comprises at least four angled surfaces.

6 . The flame detector of claim 1 , further comprising one or more electrical elements configured to process data from the receiver.

7 . The flame detector of claim 6 , wherein the one or more electrical element is configured to determine when the electromagnetic radiation received by the receiver is lower than a predetermined number, and to indicate an obscuration fault when the electromagnetic radiation received by the receiver is lower than the predetermined number.

8 . The flame detector of claim 1 , wherein the electromagnetic radiation is reflected more than once by the angled surfaces and passes at least twice through the window.

9 . The flame detector of claim 1 , wherein the reflections are carried out in a plane parallel to the window surface.

10 . The flame detector of claim 1 , wherein the plurality of angled surfaces comprises a material and surface finish that are substantially reflective to the electromagnetic radiation emitted by the transmitter.

11 . The flame detector of claim 1 , wherein the transmitter and the receiver are located within the housing.

12 . The flame detector of claim 1 , wherein the plurality of angled surfaces is located within the housing.

13 . The flame detector of claim 1 , wherein the plurality of angled surfaces is located within a plane of the window.

14 . The flame detector of claim 1 , wherein the plurality of angled surfaces is located above a plane of the window.

15 . The flame detector of claim 1 , wherein the plurality of angled surfaces is located below a plane of the window.

16 . The flame detector of claim 1 , wherein the plurality of angled surfaces are made of concave or flat surfaces that can reflect and focus the electromagnetic radiation.

17 . The flame detector of claim 1 , wherein the window is made of transparent material that can transmit the electromagnetic radiation in working frequency.

18 . The flame detector of claim 1 , further comprising a flame detection element configured to detect electromagnetic radiation passing through the window from the exterior of the housing to the interior of the housing, and configured to determine if a flame is detected within the field-of-view of the window.

19 . A detection system configured to detect obscuration of a window of a flame detector, the detection system comprising:
a transmitter configured to emit electromagnetic radiation; a receiver configured to receive electromagnetic radiation emitted by the transmitter; and a plurality of angled surfaces configured to direct the electromagnetic radiation from the transmitter through at least a portion of the window of the flame detector and toward the receiver.

20 . A method for detecting obscuration of a window of a flame detector, the method comprising:
emitting electromagnetic radiation from a transmitter located proximate to the window; directing the electromagnetic radiation, by a reflective surface, into a plane parallel to the plane of the window; directing the electromagnetic radiation, by a reflective surface, at least once within the plane parallel to the plane of the window; directing the electromagnetic radiation, by a reflective surface, out of the plane at least parallel to the plane of the window toward a receiver; detecting, by the receiver, the electromagnetic radiation; and determining when the detected electromagnetic radiation is below a predetermined threshold.

Assignees

• Honeywell Int Inc

Inventors

• Garg Amit
• Bommakanti Raja Pratap
• Ratnaparkhe Akshay Krishnaji
• Mallela Bharat Kumar

Classifications

• G08B29/043

  of fire detection circuits · CPC title

• G01J5/0896 Primary

  using a light source, e.g. for illuminating a surface · CPC title

• G01N21/15

  Preventing contamination of the components of the optical system or obstruction of the light path · CPC title

• G01J5/0014

  for sensing the radiation from gases, flames · CPC title

• G08B17/12

  Actuation by presence of radiation or particles, e.g. of infrared radiation or of ions · CPC title