System and method for monitoring status of a visual signal device

• US 20060066447A1
• Filed: 09/30/2004
• Published: 03/30/2006
• Est. Priority Date: 09/30/2004
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Tolliver, Todd Ryan, Hershey, John Erik, Davenport, David Michael
• Granted Patent: US 7,270,442 B2
• Time in Patent Office: Days
• US Class Current: 340/458
• CPC Class Codes: B61L 2207/02 using light-emitting diodes [LEDs]
• CPC Class Codes: B61L 5/1881 Wiring diagrams for power supply, control or testing
• CPC Class Codes: H05B 45/58 involving end of life detection of LEDs

Abstract

System and method for monitoring status of a visual signal lamp. The system includes at least one optical fiber comprising a first end and a second end. The first end is positioned proximate to the signal lamp and is oriented to capture a portion of light signal emitted by the signal lamp when the signal lamp is illuminated. The system also includes a photodetector positioned proximate to the second end of the optical fiber and configured to receive the portion of light signal. The system further includes a threshold detection circuitry connected to the photodetector and configured to detect a lighting parameter in relation to the signal lamp according to a predetermined criterion.

Claims

1. A system for monitoring status of a visual signal lamp comprising:

at least one optical fiber comprising a first end and a second end, said first end positioned proximate to said signal lamp and oriented to capture a portion of light signal emitted by said signal lamp when said signal lamp is illuminated;

a photodetector positioned proximate to said second end and configured to receive said portion of light signal; and

a threshold detection circuitry connected to said photodetector and configured to detect a lighting parameter in relation to said signal lamp according to a predetermined criterion.

2. The system according to claim 1, wherein said photodetector comprises at least one selected from the group consisting of a photodiode, a phototransistor, a photomultiplier, and combinations thereof.

3. The system according to claim 1 wherein said first end comprises a lens.

4. The system according to claim 1 wherein said lamp is enclosed in a lamp housing and said first end is positioned external to said housing.

5. The system according to claim 1 wherein said lamp is enclosed in a lamp housing and said first end is positioned internal to said housing.

6. The system according to claim 1 further comprising at least one lens positioned between said signal lamp and said first end of said optical fiber and configured to focus said light signal emitted by said signal lamp.

7. The system according to claim 1 further comprising at least one wavelength filter positioned between said signal lamp and said first end of said optical fiber and configured to pass a light signal having a wavelength within a predetermined range.

9. The system according to claim 1, wherein said lighting parameter comprises at least one selected from the group consisting of an intensity of light signal emitted by said signal lamp, a voltage across a lamp-head of said signal lamp, a flash rate of said signal lamp, and any combination thereof.

10. The system according to claim 9, further comprising a lamp-head voltage detection circuitry configured to detect said voltage across said lamp-head of said signal lamp or a flash rate of said signal lamp.

11. The system according to claim 10, further comprising a light frequency filter configured to separate a light signal from said lamp-head voltage detection circuitry from said portion of light signal emitted by said signal lamp.

12. The system according to claim 1 further comprising a logical processor connected to said threshold detection circuitry and configured to determine a status of said signal lamp based on said lighting parameter.

13. The system according to claim 12, wherein said predetermined criterion comprises a binary condition for detection of said portion of light signal received by said photodetector.

14. The system according to claim 12, wherein said predetermined criterion comprises a maximum threshold for detection of said portion of light signal received by said photodetector.

15. The system according to claim 12, wherein said predetermined criterion comprises a minimum threshold for detection of said portion of light signal received by said photodetector.

16. The system according to claim 12 further comprising an alerting system, wherein said logical processor is configured to send an alarm signal to said alerting system when there is a determined change in status of said signal lamp.

17. The system according to claim 1 further comprising a continuity checking circuitry configured to check continuity of said at least one optical fiber.

18. The system according to claim 17, wherein said continuity checking circuitry comprises:

at least one additional optical fiber comprising a first end and a second end, wherein said additional optical fiber is coupled to said at least one optical fiber;

a light source positioned proximate to said first end of said at least one additional optical fiber and configured to emit light signal through said additional optical fiber;

a fiber optic splitter coupled to said first end of said at least one additional optical fiber and configured to split a light signal emitted by said light source such that one portion of said light signal passes through said at least one additional optical fiber and another portion of said light signal passes through said at least one optical fiber; and

an additional photodetector positioned proximate to said second end of said at least one additional optical fiber.

8. The system according to claim 8, wherein said predetermined range comprises range of wavelength corresponding to at least one selected from the group consisting of red, yellow, green colors, and any combination thereof.

19. A system for monitoring status of a visual signal lamp comprising:

at least one optical fiber comprising a first end and a second end, said first end positioned proximate to said signal lamp and oriented to capture a portion of light signal emitted by said signal lamp when said signal lamp is illuminated;

a photodetector positioned proximate to said second end and configured to receive said portion of light signal, wherein said photodetector comprises at least one selected from the group consisting of a photodiode, a phototransistor, a photomultiplier, and combinations thereof;

a threshold detection circuitry connected to said photodetector and configured to detect a lighting parameter in relation to said signal lamp according to a predetermined criterion, wherein said lighting parameter comprises at least one selected from the group consisting of an intensity of light signal emitted by said signal lamp, a voltage across a lamp-head of said signal lamp, a flash rate of said signal lamp, and any combination thereof;

a logical processor connected to said threshold detection circuitry and configured to determine a status of said signal lamp based on said lighting parameter; and

an alerting system, wherein said logical processor is configured to send an alarm signal to said alerting system when there is a determined change in status of said signal lamp.

20. A visual signal system comprising:

at least one signal lamp;

at least one first optical fiber comprising a first end and a second end, wherein said first end is positioned proximate to said signal lamp and oriented to capture a portion of light signal emitted by said signal lamp when said signal lamp is illuminated;

a photodetector positioned proximate to said second end of said first optical fiber and configured to receive said portion of light signal;

a continuity checking circuitry coupled to said first optical fiber and configured to check an continuity of said at least one first optical fiber; and

a threshold detection circuitry connected to said photodetector and configured to detect a lighting parameter in relation to said signal lamp according to a predetermined criterion.

wherein said lamp is enclosed in a lamp housing.

21. The system according to claim 20, wherein said photodetector comprises at least one selected from the group consisting of a photodiode, a phototransistor, a photomultiplier, and any combination thereof.

22. The system according to claim 20, wherein said at least one signal lamp comprises a plurality of signal lamps.

23. The system according to claim 20 further comprising at least one optical switch positioned proximate to said first end of said optical fiber and configured to select at least one of said plurality of signal lamps for determining said status of.

24. The system according to claim 20, wherein said first end comprises a lens.

25. The system according to claim 20, wherein said first end is positioned external to said housing.

26. The system according to claim 20, wherein said first end is positioned internal to said housing.

27. The system according to claim 20 further comprising at least one lens positioned between said signal lamp and said first end of said optical fiber and configured to focus said light signal emitted by said signal lamp.

28. The system according to claim 20 further comprising at least one wavelength filter positioned between said signal lamp and said first end of said optical fiber and configured to pass a light signal having a wavelength within a predetermined range.

29. The system according to claim 27, wherein said predetermined range comprises range of wavelength corresponding to at least one selected from the group consisting of red, yellow, green colors, and any combination thereof.

30. The system according to claim 20, wherein said lighting parameter comprises at least one selected from the group consisting of an intensity of light signal emitted by said signal lamp, a voltage across a lamp-head of said signal lamp, a flash rate of said signal lamp, and any combination thereof.

31. The system according to claim 30, further comprising a lamp-head voltage detection circuitry configured to detect said voltage across said lamp-head of said signal lamp or a flash rate of said signal lamp.

32. The system according to claim 31, further comprising a light frequency filter configured to separate a light signal from said lamp-head voltage detection circuitry from said portion of light signal emitted by said signal lamp.

33. The system according to claim 20 further comprising a logical processor connected to said threshold detection circuitry and configured to determine a status of said signal lamp based on said lighting parameter.

34. The system according to claim 33, wherein said predetermined criterion comprises a binary condition for detection of said portion of light signal received by said photodetector.

35. The system according to claim 33, wherein said predetermined criterion comprises a maximum threshold of said portion of light signal received by said photodetector.

36. The system according to claim 20, wherein said predetermined criterion comprises a minimum threshold of said portion of light signal received by said photodetector.

37. The system according to claim 20 further comprising an alerting system, wherein said logical processor is configured to send an alarm signal to said alerting system when there is a determined change in status of said signal lamp.

38. The system according to claim 20, wherein said continuity checking circuitry further comprises:

at least one test optical fiber comprising a first end and a second end, wherein said test optical fiber is coupled to said at least one optical fiber;

a light source positioned proximate to said first end of said at least one test optical fiber;

a fiber optic splitter coupled to said first end of said at least one test optical fiber and configured to split a light signal emitted by said light source such that one portion of said light signal passes through said at least one additional optical fiber and another portion of said light signal passes through said at least one optical fiber; and

a test photodetector positioned proximate to said second end of said at least one test optical fiber and configured to detect said light signal emitted from said light source.

39. A method for monitoring status of a visual signal lamp comprising:

positioning at least one optical fiber proximate to said signal lamp and orienting said at least one optical fiber to capture a portion of light signal emitted by said signal lamp when said signal lamp is illuminated;

capturing a portion of light signal emitted by said signal lamp using said at least one optical fiber when said signal lamp is illuminated; and

detecting a lighting parameter in relation to said signal lamp according to a predetermined criterion.

40. The method according to claim 39, wherein said detecting comprises detecting using a photodetecting.

41. The method according to claim 39, wherein said lighting parameter comprises at least one selected from the group consisting of an intensity of light signal emitted by said signal lamp, a voltage across a lamp-head of said signal lamp, a flash rate of said signal lamp, and any combination thereof.

42. The method according to claim 41, further comprising generating a light signal based on said voltage across said lamp-head.

43. The method according to claim 42, further comprising modulating an amplitude of said light signal based on said voltage across said lamp-head.

44. The method according to claim 42, further comprising separating said light signal based on said voltage across said lamp-head from said portion of light signal emitted by said signal lamp.

45. The method according to claim 44, wherein said separating comprises separating using a light frequency filter.

46. The method according to claim 39 further comprising determining a status of said signal lamp based on said lighting parameter using a logical processor.

47. The method according to claim 46, wherein said predetermined criterion comprises comparing said intensity of said portion of light signal to a predetermined threshold detection value using a binary condition.

48. The method according to claim 46, wherein said predetermined criterion comprises comparing said intensity of said portion of light signal to a predetermined maximum value of intensity as threshold for detection of said intensity of said portion of light signal.

49. The method according to claim 46, wherein said predetermined criterion comprises comparing said intensity of said portion of light signal to a predetermined minimum value of intensity as threshold for detection of said intensity of said portion of light signal.

50. The method according to claim 39, wherein said lamp is enclosed in a lamp housing and said capturing said portion of light signal comprises capturing outside said housing.

51. The method according to claim 39, wherein said lamp is enclosed in a lamp housing and said capturing said portion of light signal comprises capturing inside said housing.

52. The method according to claim 39 further comprising passing a light signal having a wavelength within a predetermined range using a wavelength filter before said capturing.

53. The method according to claim 52, wherein said passing said light signal comprises passing a light signal having a wavelength within a range of wavelength corresponding to at least one selected from the group consisting of red, yellow, green colors, and any combination thereof.

54. The method according to claim 39 further comprising focusing said light signal emitted by said signal lamp before said capturing.

55. The method according to claim 39 further comprising sending an alarm signal when said change in status of said signal lamp is determined.

56. The method according to claim 39 further comprising checking continuity of said at least one optical fiber.

57. The method according to claim 56, wherein said checking continuity further comprises:

coupling at least one additional optical fiber comprising a first end and a second end to said at least one optical fiber;

sending a test light signal through said first end of said additional optical fiber;

splitting said test light signal emitted by said light source such that one portion of said test light signal passes through said at least one additional optical fiber and another portion of said test light signal passes through said at least one optical fiber; and

detecting said another portion of said test light signal coming out through said second end of said additional optical fiber.