Recessed LED down light

• US 8,022,641 B2
• Filed: 05/01/2009
• Issued: 09/20/2011
• Est. Priority Date: 05/01/2009
• Status: Expired due to Fees

• Current Assignee: Focal Point LLC (Legrand SA)
• Original Assignee: Focal Point LLC (Legrand SA)
• Inventors: Thornton, Peter F. Jr., Janik, Raymond, Yuen, Stephen H., Doubek, David E., Thornton, Michael T.
• Primary Examiner(s): LE, DON P
• Application Number:
  US12/434,452
• Publication Number:
  US 20100277905A1
• Time in Patent Office: 872 Days
• Field of Search: 315/250, 315/209.R, 315/185.R, 315/291, 315/294, 315/297, 315/312, 315/313, 362/249.02, 362/249.06, 445/23
• US Class Current: 315/297
• CPC Class Codes: F21K 9/00 Light sources using semiconductor devices as light-generating elements, e.g. using light-emitting diodes [LED] or lasers
• CPC Class Codes: F21S 8/026 intended to be recessed in a ceiling or like overhead structure, e.g. suspended ceiling
• CPC Class Codes: F21V 23/005 the substrate is supporting also the light source
• CPC Class Codes: F21V 29/763 the planes containing the fins or blades having the direction of the light emitting axis
• CPC Class Codes: F21V 29/767 the planes containing the fins or blades having directions perpendicular to the light emitting axis
• CPC Class Codes: F21Y 2105/10 comprising a two-dimensional array of point-like light-generating elements
• CPC Class Codes: F21Y 2113/13 comprising an assembly of point-like light sources
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H05B 45/30 Driver circuits
• CPC Class Codes: H05K 1/181 associated with surface mounted components
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

In an embodiment of the present invention, a light emitting diode (LED) recessed down light fixture comprises a housing, a reflector assembly mounted to the housing, and an LED circuit board attached to the housing over the reflector assembly. The LED circuit board includes a plurality of resistors electrically connected to the LED circuit board, a bridge rectifier, and a plurality of at least 80 miniature LEDs electrically connected to the LED circuit board and configured to provide light. The plurality of miniature LEDs are separated into a plurality of LED clusters. Each cluster is electrically connected to at least one resistor. Further, the plurality of miniature LEDs are arranged in a configuration such that a voltage differential across any two proximate LEDs is less than 36 volts. The down light fixture further comprises a lens cover attached to the top end of the reflector assembly.

Claims

1. A light-emitting diode (LED) circuit board connected to an AC power source used for a recessed down light fixture, comprising:

a plurality of resistors electrically connected to the LED circuit board;

a bridge rectifier electrically connected to the LED circuit board for converting the AC power to DC power; and

a plurality of at least 80 miniature LEDs electrically connected to the LED circuit board and configured to provide an appearance of a single light source, wherein the plurality of miniature LEDs are separated into a plurality of LED clusters, each LED cluster electrically connected to at least one resistor, and further wherein the plurality of miniature LEDs are arranged in a configuration such that a voltage differential across any two proximate LEDs is less than 36 volts.

2. The LED circuit board of claim 1, wherein the voltage differential between any two proximate LEDs is less than 24 volts.

3. The LED circuit board of claim 1, wherein the plurality of miniature LEDs are arranged in a circular pattern configured to provide a uniform light appearance.

4. The LED circuit board of claim 1, wherein each LED cluster includes at least 20 miniature LEDs.

5. The LED circuit board of claim 1, wherein the LED circuit board includes at least 4 LED clusters.

6. The LED circuit board of claim 1, wherein each LED cluster includes at least 42 miniature LEDs.

7. The LED circuit board of claim 1, wherein the LED circuit board includes at least 6 LED clusters.

8. The LED circuit board of claim 1, further comprising a plurality of capacitors electrically connected to the circuit board.

9. The LED circuit board of claim 1, further comprising a pair of fuses electrically connected to the LED circuit board.

10. The LED circuit board of claim 9, wherein a first fuse is utilized as a safety fuse to protect the circuit board from voltage surges.

11. The LED circuit board of claim 10, wherein a second fuse is utilized as a switching fuse to operate the light fixture between two light output modes, a high light output mode and a low output mode.

12. The LED circuit board of claim 11, wherein the second fuse is preinstalled to operate the light fixture in the high light output mode.

13. The LED circuit board of claim 11, wherein the second fuse is not preinstalled to operate the light fixture in the low light output mode.

14. The LED circuit board of claim 1, wherein the circuit board further comprises a surge suppressor to protect against voltage surges.

15. A light-emitting diode (LED) circuit board connected to a power source used for a recessed down light fixture, comprising:

a plurality of resistors electrically connected to the LED circuit board;

a bridge rectifier electrically connected to the LED circuit board;

a pair of fuses electrically connected to the LED circuit board, wherein the pair of fuses includes a first fuse and a second fuse; and

a plurality of miniature LEDs electrically connected to the LED circuit board, wherein the plurality of miniature LEDs provide a light source in one of two factory-selectable modes, the first mode being operable with the second fuse preinstalled and the second mode being operable with the second fuse not preinstalled, further, wherein the first mode is a high light output and the second mode is a low light output.

16. A light-emitting diode (LED) recessed down light fixture, comprising:

a housing having four side panels and a top panel;

a bottom frame attached to the housing, wherein the bottom frame has an aperture;

a reflector assembly mounted to the housing through the aperture;

an LED circuit board attached to the inside of the top panel of the housing over the reflector assembly comprising,

a plurality of resistors electrically connected to the LED circuit board,

a bridge rectifier electrically connected to the LED circuit board for converting the AC power to DC power, and

a plurality of at least 80 miniature LEDs electrically connected to the LED circuit board and configured to provide light, wherein the plurality of miniature LEDs are separated into a plurality of LED clusters, each cluster electrically connected to at least one resistor, and further wherein the plurality of miniature LEDs are arranged in a configuration such that a voltage differential across any two proximate LEDs is less than 36 volts; and

a lens cover attached to the top end of the reflector assembly configured to cover the LED circuit board.

17. The LED recessed down light fixture of claim 16, wherein the voltage differential is less than 24 volts.

18. The LED recessed down light fixture of claim 16, wherein the plurality of miniature LEDs are arranged in a circular pattern configured to provide an appearance of a single light source.

19. The LED recessed down light fixture of claim 16, wherein each LED cluster includes at least 20 miniature LEDs.

20. The LED recessed down light fixture of claim 16, wherein the LED circuit board includes at least 4 LED clusters.

21. The LED recessed down light fixture of claim 16, wherein each LED cluster includes at least 42 miniature LEDs.

22. The LED recessed down light fixture of claim 16, wherein the LED circuit board includes at least 6 LED clusters.

23. The LED recessed down light fixture of claim 16, wherein the LED circuit board further comprising a plurality of capacitors electrically connected to the circuit board.

24. The LED recessed down light fixture of claim 16, further comprising a pair of fuses electrically connected to the LED circuit board.

25. The LED recessed down light fixture of claim 24, wherein a first fuse is utilized as a safety fuse to protect the circuit board from voltage surges.

26. The LED recessed down light fixture of claim 24, wherein a second fuse is utilized as a switching fuse to operate the light fixture between two light output modes, a high light output mode and a low output mode.

27. The LED recessed down light fixture of claim 26, wherein the second fuse is preinstalled to operate the light fixture in the high light output mode.

28. The LED recessed down light fixture of claim 26, wherein the second fuse is not preinstalled to operate the light fixture in the low light output mode.

29. The LED recessed down light fixture of claim 16, wherein the circuit board further comprises a surge suppressor to protect against voltage surges.

30. The LED recessed down light fixture of claim 16, wherein the lens cover includes a lens reflector that focuses the light from the LEDs into the reflector assembly.

31. The LED recessed down light fixture of claim 16, wherein the housing is aluminum.

32. The LED recessed down light fixture of claim 16, wherein the reflector assembly has a top end and a bottom end and the top end is installed within the aperture, and the bottom end protrudes from the housing.

33. The LED recessed down light fixture of claim 16, wherein the light fixture further comprises a junction box mounted to one of the side panels of the housing and a divider attached to the frame located between the aperture and the junction box.

34. The LED recessed down light fixture of claim 16, wherein the light fixture further comprises an external capacitor electrically connected to the LED circuit board and mounted inside a junction box.

35. The LED recessed down light fixture of claim 16, wherein the light fixture further comprises a plurality of mounting brackets attached to the side panels of the housing.

36. The LED recessed down light fixture of claim 16, wherein the light fixture further comprises a thermal protector located within the housing and configured to stop the power when the thermal protector detects excessive heat within the housing.

37. The LED recessed down light fixture of claim 16, wherein the light fixture further comprises a heat sink.

38. The LED recessed down light fixture of claim 37, wherein the heat sink is mounted on top of the top panel of the housing.

39. The LED recessed down light fixture of claim 37, wherein the height of the light fixture with the heat sink mounted is no more than ¼

inch taller than the height of the light fixture without the heat sink mounted.

40. The LED recessed down light fixture of claim 37, wherein the heat sink comprises of a flat member mounted to the top panel of the housing and a fin member that extends horizontally from the flat member and the front panel of the housing.

41. The LED recessed down light fixture of claim 40, wherein the fin member of the heat sink comprises a set of vertical fins and horizontal fins configured in a square wave pattern.

42. A method for manufacturing light fixtures comprising a plurality of LEDs where each of the plurality of LEDs is supplied in manner that corresponds to one of a plurality of presorted bins, the method comprising the steps of:

(a) continuously determining a percentage of LEDs corresponding to each of the plurality of bins;

(b) continuously determining a first bin that corresponds to the percentage of LEDs with a highest incidence;

(c) continuously determining a second bin that corresponds to percentage of LEDs with a second highest incidence;

(d) electrically connecting the plurality of LEDs to an LED circuit board, wherein the LEDs are separated into a plurality of LED clusters, wherein the LED circuit board comprises;

a first LED cluster with two parts, a first part with LEDs from the first bin and a second part with LEDs from the second bin, the number of LEDs from the first bin and the second bin approximately equal; and

a second LED cluster with two parts, a first part with LEDs from the first bin and a second part with LEDs from the second bin, the number of LEDs from the first bin and second bin approximately equal,

wherein the first part of the first LED cluster is proximate to the second part of the second LED cluster and the second part of the first LED cluster is proximate to the first part of the second LED cluster.

43. The method of claim 42, wherein the plurality of LEDs are arranged in a circular pattern configured to provide an appearance of a single light source.

44. The method of claim 42, wherein each cluster contains 42 LEDs.

45. The method of claim 42, wherein the LED circuit board contains at least 6 LED clusters.

46. The method of claim 42, wherein the LED circuit board further comprises a third LED cluster with two parts, a first part with LEDs from the first bin and a second part with LEDs from the second bin, the number of LEDs from the first bin and second bin approximately equal, wherein the first part of the second LED cluster is proximate to the second part of the third LED cluster and the second part of the second LED cluster is proximate to the first part of the third LED cluster.

47. The method of claim 46, wherein the LED circuit board further comprises a fourth LED cluster with two parts, a first part with LEDs from the first bin and a second part with LEDs from the second bin, the number of LEDs from the first bin and second bin approximately equal, wherein the first part of the third LED cluster is proximate to the second part of the fourth LED cluster and the second part of the third LED cluster is proximate to the first part of the fourth LED cluster.

48. The method of claim 47, wherein the LED circuit board further comprises a fifth LED cluster with two parts, a first part with LEDs from the first bin and a second part with LEDs from the second bin, the number of LEDs from the first bin and second bin approximately equal, wherein the first part of the fourth LED cluster is proximate to the second part of the fifth LED cluster and the second part of the fourth LED cluster is proximate to the first part of the fifth LED cluster.

49. The method of claim 48, wherein the LED circuit board further comprises a sixth LED cluster with two parts, a first part with LEDs from the first bin and a second part with LEDs from the second bin, the number of LEDs from the first bin and second bin approximately equal, wherein the first part of the fifth LED cluster is proximate to the second part of the sixth LED cluster and the second part of the fifth LED cluster is proximate to the first part of the sixth LED cluster.