Methods and Apparatus for LED Lighting with Heat Spreading in Illumintion Gaps

• US 20090316408A1
• Filed: 06/23/2008
• Published: 12/24/2009
• Est. Priority Date: 06/23/2008
• Status: Active Grant

• Current Assignee: IDEAL Industries Lighting, LLC (Ideal Industries Incorporated)
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Villard, Russell G.
• Granted Patent: US 7,976,202 B2
• Time in Patent Office: Days
• US Class Current: 362/249.130
• 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 4/28 rigid, e.g. LED bars
• CPC Class Codes: F21S 8/06 by suspension
• CPC Class Codes: F21V 17/00 Fastening of component parts of lighting devices, e.g. shades, globes, refractors, reflectors, filters, screens, grids or protective cages of light sources or light holders F21V19/00
• CPC Class Codes: F21V 21/02 Wall, ceiling, or floor bases; Fixing pendants or arms to the bases F21V21/08 takes precedence; bases for movable standing lamps F21V21/06
• CPC Class Codes: F21V 29/00 Protecting lighting devices from thermal damage; Cooling or heating arrangements specially adapted for lighting devices or systems lighting fixtures combined with outlets for air-treatment systems F24F13/078
• CPC Class Codes: F21V 29/74 with fins or blades
• CPC Class Codes: F21V 29/83 the elements having apertures, ducts or channels, e.g. heat radiation holes
• CPC Class Codes: F21V 29/85 characterised by the material liquid coolants F21V29/56
• CPC Class Codes: F21Y 2103/10 comprising a linear array of point-like light-generating elements
• CPC Class Codes: F21Y 2107/00 Light sources with three-dimensionally disposed light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: Y10T 29/49002 Electrical device making
• CPC Class Codes: Y10T 29/4913 Assembling to base an electrical component, e.g., capacitor, etc.

Abstract

Techniques for light emitting diode (LED) lighting with heat spreading in illumination gaps. Inexpensive structural aluminum may be suitably employed to form a passive heat spreading mount for plural LEDs whose illumination collectively combines to provide the light needed by a particular lighting fixture, such as a pendant chandelier, by way of example, by angling fins of the passive heat spreading mount to correspond to illumination gaps of the LEDs.

Claims

1. A heat spreading light emitting diode (LED) mounting arrangement comprising:

a heat spreading base unit having plural flat mounting areas with each of said plural flat mounting areas having one or more associated angled fins; and

at least two LEDs mounted on at least two of the plural flat mounting areas, said at least two LEDs having a viewing angle so that in operation a substantial majority of emitted light from said at least two LEDs is within the viewing angles wherein said one or more associated angled fins have an angle so that said fins are located in illumination gaps of said at least two LEDs.

2. The heat spreading LED mounting arrangement of claim 1 wherein the heat spreading base unit is formed of structural aluminum.

3. The heat spreading LED mounting arrangement of claim 1 further comprising:

an end cap unit supporting a further LED mounting arrangement thereon.

4. The heat spreading LED mounting arrangement of claim 1 wherein said at least two LEDs are spaced along a length of said base unit.

5. The heat spreading LED mounting arrangement of claim 1 wherein four LEDs are mounted about a central axis of the base unit and eight angled fins are angled at an angle γ

of approximately 45°

with respect to normals, N, to four flat mount areas on which the four LEDs are mounted.

6. The heat spreading LED mount of claim 5 wherein the four LEDs in operation provide 360°

illumination.

7. The heat spreading base unit of claim 1 wherein portions of said base unit contacting said at least two LEDs have a conductivity of at least approximately 160°

C./watt.

8. The heat spreading base unit of claim 1 wherein said base unit comprises two T-shaped bars with their bases secured together.

9. The heat spreading base unit of claim 8 wherein a layer of thermal gap material is clamped between said bases of the T-shaped bars.

10. The heat spreading LED mounting arrangement of claim 1 wherein said at least two LEDs have a viewing angle of 90°

.

11. The heat spreading LED mounting arrangement of claim 1 wherein in said illumination gaps the intensity of light emitted by said LEDs is less than 50% of the maximum intensity of light emitted thereby.

12. A method of mounting light emitting diodes (LEDs) to avoid hot spots comprising:

utilizing a heat spreading base unit having plural flat mounting areas with each of said plural flat mounting areas having one or more associated angled fins; and

mounting at least two LEDs on at least two of the plural flat mounting areas, said at least two LEDs having a viewing angle so that in operation a substantial majority of emitted light from said at least two LEDs is within the viewing angle, wherein said one or more associated angled fins have an angle so that said fins are located in illumination gaps of said at least two LEDs.

13. The method of claim 12 farther comprising:

mounting an end cap unit supporting a further LED on an end of the base unit.

14. The method of claim 12 further comprising:

spacing the two LEDs along a length of said base unit.

15. The method of claim 12 wherein four LEDs are mounted about a central axis of the base unit and eight angled fins are angled at an angle γ

of approximately 45°

with respect to normals, N, to four flat mount areas on which the four LEDs are mounted.

16. The method of claim 12 wherein portions of said base unit contacting said at least two LEDs have a conductivity of at least approximately 160°

C./watt.

17. The method of claim 12 further comprising:

forming said base unit from two T-shaped bars with their bases secured together.

18. The method of claim 17 wherein a layer of thermal gap material is clamped between said bases of the T-shaped bars.

19. The method of claim 12 wherein said at least two LEDs have a viewing angle of 90°

.

20. The method of claim 12 wherein in said illumination gaps the intensity of light emitted by said LEDs is less than 50% of the maximum intensity of light emitted thereby.