Lamp assembly adapted to illuminate a backlit sign

• US 20080019142A1
• Filed: 06/29/2006
• Published: 01/24/2008
• Est. Priority Date: 06/29/2006
• Status: Abandoned Application

• Current Assignee: Thomas & Betts International Incorporated (ABB Limited)
• Original Assignee: Thomas & Betts International Incorporated (ABB Limited)
• Inventors: Lambert, Michel, Xing, Zhi Gang, Rapeanu, Radu-Cornel
• Application Number:
  US11/477,304
• Publication Number:
  US 20080019142A1
• Time in Patent Office: Days
• US Class Current: 362/555
• CPC Class Codes: F21K 9/232 specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G09F 9/33 being semiconductor devices, e.g. diodes
• CPC Class Codes: H05K 1/18 Printed circuits structurally associated with non-printed electric components H05K1/0201, H05K1/023, H05K1/0243, and H05K1/16 take precedence
• CPC Class Codes: H05K 2201/09418 Special orientation of pads, lands or terminals of component, e.g. radial or polygonal orientation
• CPC Class Codes: H05K 2201/10106 Light emitting diode [LED]
• CPC Class Codes: H05K 2201/10484 Obliquely mounted

Abstract

A lamp assembly and method for illuminating a backlit sign include at least one circuit board and light emitting diodes mounted on the circuit board. The light emitting diodes are oriented such that a majority of emitted light or a beam from the circuit board is directed to only a portion of the backlit sign. The light emitting diodes are positioned uniformly around a perimeter of the circuit board to ensure uniform illumination around the lamp assembly. The circuit boards are arranged parallel to each other and perpendicular to a longitudinal axis of the lamp assembly. The lamp assembly includes a plurality of resistors mounted on the circuit board such that heat dissipated by the resistors is uniformly distributed over the circuit board. The lamp assembly also includes a Bridge rectifier to provide a DC output voltage from AC or DC input voltages.

Claims

1. A lamp assembly adapted to illuminate a backlit sign comprising:

at least one circuit board comprising a surface; and

a plurality of light emitting diodes mounted on the at least one circuit board, the plurality of light emitting diodes being oriented with respect to the surface of the at least one circuit board such that a beam of light emitted from the at least one circuit board is directed to a portion of the backlit sign.

2. The lamp assembly adapted to illuminate a backlit sign defined by claim 1, further comprising a plurality of circuit boards arranged substantially parallel to each other.

3. The lamp assembly adapted to illuminate a backlit sign defined by claim 1, wherein the lamp assembly comprises a longitudinal axis, the lamp assembly further comprising a plurality of circuit boards arranged substantially perpendicular to the longitudinal axis of the lamp assembly.

4. The lamp assembly adapted to illuminate a backlit sign defined by claim 1, wherein the lamp assembly is adapted for use in a hazardous location.

5. The lamp assembly adapted to illuminate a backlit sign defined by claim 1, further comprising a plurality of resistors mounted on the at least one circuit board such that heat dissipated by the plurality of resistors is substantially uniformly distributed over the at least one circuit board.

6. The lamp assembly adapted to illuminate a backlit sign defined by claim 1, further comprising a Bridge rectifier adapted to provide a DC output voltage for the plurality of light emitting diodes from at least one of an AC input voltage and a DC input voltage.

7. The lamp assembly adapted to illuminate a backlit sign defined by claim 1, wherein the plurality of light emitting diodes is oriented at least one of 0 degrees, 22 degrees, and 45 degrees with respect to the surface of the at least one circuit board.

8. The lamp assembly adapted to illuminate a backlit sign defined by claim 1, wherein the lamp assembly is adapted to operate from at least one of a 6-volt input voltage, 12-volt input voltage, 24-volt input voltage, and 120-volt input voltage.

9. The lamp assembly adapted to illuminate a backlit sign defined by claim 1, wherein the lamp assembly is adapted to operate from at least one of an AC input voltage and a DC input voltage.

10. The lamp assembly adapted to illuminate a backlit sign defined by claim 1, further comprising a plurality of light emitting diodes, each of the plurality of light emitting diodes is oriented at substantially the same angle with respect to the surface of the at least one circuit board.

11. The lamp assembly adapted to illuminate a backlit sign defined by claim 1, wherein the lamp assembly requires less than 5 Watts of power.

12. The lamp assembly adapted to illuminate a backlit sign defined by claim 1, wherein the plurality of light emitting diodes are mounted uniformly around a perimeter of the at least one circuit board.

13. A lamp assembly adapted to illuminate a backlit sign comprising:

at least one circuit board comprising a surface;

a plurality of light emitting diodes mounted on the at least one circuit board; and

a plurality of resistors mounted on the at least one circuit board such that heat dissipated by the plurality of resistors is substantially uniformly distributed over the at least one circuit board.

14. A method of illuminating a backlit sign comprising:

providing at least one circuit board comprising a surface; and

mounting a plurality of light emitting diodes on the at least one circuit board, the plurality of light emitting diodes being oriented with respect to the surface of the at least one circuit board such that a beam of light emitted from the at least one circuit board is directed to a portion of the backlit sign.

15. The method of illuminating a backlit sign defined by claim 14, further comprising arranging a plurality of circuit boards substantially parallel to each other.

16. The method of illuminating a backlit sign defined by claim 14, wherein the lamp assembly comprises a longitudinal axis, further comprising arranging a plurality of circuit boards substantially perpendicular to the longitudinal axis of the lamp assembly.

17. The method of illuminating a backlit sign defined by claim 14, further comprising adapting the lamp assembly for use in a hazardous location.

18. The method of illuminating a backlit sign defined by claim 14, further comprising positioning a plurality of resistors on the at least one circuit board such that heat dissipated by the plurality of resistors is substantially uniformly distributed over the at least one circuit board.

19. The method of illuminating a backlit sign defined by claim 14, further comprising providing a DC output voltage for the plurality of light emitting diodes from at least one of an AC input voltage and a DC input voltage.

20. The method of illuminating a backlit sign defined by claim 14, further comprising orienting the at least one light emitting diode at least one of 0 degrees, 22 degrees, and 45 degrees with respect to the surface of the at least one circuit board.

21. The method of illuminating a backlit sign defined by claim 14, further comprising adapting the lamp assembly to operate from at least one of a 6-volt input voltage, 12-volt input voltage, 24-volt input voltage, and 120-volt input voltage.

22. The method of illuminating a backlit sign defined by claim 14, further comprising adapting the lamp assembly to operate from at least one of an AC input voltage and a DC input voltage.

23. The method of illuminating a backlit sign defined by claim 14, further comprising orienting the plurality of light emitting diodes at substantially the same angle with respect to the surface of the at least one circuit board.

24. The method of illuminating a backlit sign defined by claim 14, further comprising adapting the lamp assembly to operate with less than 5 Watts of power.

25. The method of illuminating a backlit sign defined by claim 14, further comprising mounting the plurality of light emitting diodes uniformly around a perimeter of the at least one circuit board.

26. A method of illuminating a backlit sign comprising:

providing at least one circuit board comprising a surface;

mounting a plurality of light emitting diodes on the at least one circuit board; and

mounting a plurality of resistors on the at least one circuit board such that heat dissipated by the plurality of resistors is substantially uniformly distributed on the at least one circuit board.