Systems and methods for thermal management of lamps and luminaires using LED sources

• US 7,784,971 B2
• Filed: 11/29/2007
• Issued: 08/31/2010
• Est. Priority Date: 12/01/2006
• Status: Active Grant

• Current Assignee: ABL IP Holding LLC (Acuity Brands, Inc.)
• Original Assignee: ABL IP Holding LLC (Acuity Brands, Inc.)
• Inventors: Dorogi, Michael Jay
• Primary Examiner(s): O'Shea; Sandra L
• Assistant Examiner(s): Dunwiddie; Meghan K
• Application Number:
  US11/947,463
• Publication Number:
  US 20080130299A1
• Time in Patent Office: 1,006 Days
• Field of Search: 362/244, 362/249.02, 362/294, 362/310, 362/373, 362/800
• US Class Current: 362/294
• 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: F21V 23/04 the elements being switches safety devices F21V25/00
• CPC Class Codes: F21V 29/51 using condensation or evaporation of a fluid, e.g. heat pipes
• CPC Class Codes: F21V 29/75 with fins or blades having different shapes, thicknesses or spacing
• 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 2107/00 Light sources with three-dimensionally disposed light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

LED module assemblies and luminaires that reduce thermal issues associated with LED lamp energy dissipation are disclosed. In one embodiment, an optimized conduction path from the LED to the exterior of the luminaire is created through the use of heat pipes integrated into the LED module assembly and luminaire. In this embodiment, a significant reduction in thermal transfer to the interior of the enclosure may be implemented, while allowing maximum energy dissipation from the LEDs.

Claims

1. An apparatus comprising:

an LED module assembly comprising;

a thermal assembly comprising a heat pipe and a contact pad coupled to an exterior surface of the heat pipe;

at least one light emitting diode coupled to the contact pad; and

the heat pipe comprising a first end and a second end, wherein the first end of the heat pipe is coupled to a heat pipe mating surface

a luminaire housing, wherein an inner surface of the luminaire housing comprises a housing mating surface, and wherein the heat pipe mating surface is configured to contact and releasably mate with the housing mating surface to define a thermal junction; and

a luminaire base, wherein the luminaire base is coupled to the second end of the heat pipe and coupled to the luminaire housing, wherein the first end and the second end of the heat pipe are enclosed by the coupled luminaire housing and the luminaire base.

2. The apparatus of claim 1, further comprising an LED driver connected to the thermal assembly.

3. The apparatus of claim 1, wherein the at least one light emitting diode comprises an individual LED, an LED chip, or an LED die.

4. The apparatus of claim 1, wherein the at least one light emitting diode is coupled to the contact pad by mounting the at least one light emitting diode to a printed circuit board that is attached to the contact pad.

5. The apparatus of claim 1, wherein the at least one light emitting diode is mounted directly to a surface of the contact pad.

6. The apparatus of claim 5, wherein the contact pad has at least one groove formed on the surface of the contact pad substantially parallel and opposite at least one electrical contact area to prevent contact between the electrical contact area and the contact pad at the groove.

7. The apparatus of claim 1, further comprising a material with a low thermal conductivity substantially surrounding the at least one light emitting diode.

8. The apparatus of claim 7, wherein the material with a low thermal conductivity is a thermally insulating material.

9. The apparatus of claim 1, wherein the contact pad and the at least one light emitting diode are dimensioned to have substantially similar surface areas.

10. The apparatus of claim 1, wherein the contact pad is dimensioned to accommodate a plurality of light emitting diodes.

11. An apparatus comprising:

an LED module assembly comprising;

a thermal assembly comprising a heat pipe and a contact pad coupled to an exterior surface of the heat pipe;

at least one light emitting diode comprising a front side, a back side, and an electrical contact area, wherein the back side of the at least one light emitting diode is coupled directly to the contact pad;

a groove formed on a surface of the contact pad substantially parallel and opposite the electrical contact area to prevent contact between the electrical contact area and the contact pad at the groove;

a printed circuit board coupled to the front side of the at least one light emitting diode; and

the heat pipe comprising a first end and a second end, wherein the first end of the heat pipe is coupled to a heat pipe mating surface;

a luminaire housing, wherein an inner surface of the luminaire housing comprises a housing mating surface, and wherein the heat pipe mating surface is configured to contact and releasably mate with the housing mating surface to define a thermal junction; and

a luminaire base, wherein the luminaire base is coupled to the second end of the heat pipe and coupled to the luminaire housing, wherein the first end and the second end of the heat pipe are enclosed by the coupled luminaire housing and the luminaire base.

12. The apparatus of claim 11, wherein the at least one light emitting diode comprises an individual LED, an LED chip, or an LED die.

13. The apparatus of claim 11, further comprising a material with a low thermal conductivity substantially surrounding the at least one light emitting diode.

14. The apparatus of claim 13, wherein the material with a low thermal conductivity is a thermally insulating material.

15. The apparatus of claim 11, wherein the contact pad and the at least one light emitting diode are dimensioned to have substantially similar surface areas.

16. The apparatus of claim 11, wherein the contact pad is dimensioned to accommodate a plurality of light emitting diodes.

17. The apparatus of claim 11, further comprising an LED driver connected to the thermal assembly.

18. The apparatus of claim 17, wherein the LED driver is a PWM dimming driver.

19. An apparatus comprising:

an LED module assembly comprising;

a thermal assembly comprising a heat pipe and a contact pad coupled to an exterior surface of the heat pipe;

at least one light emitting diode coupled to the contact pad; and

the heat pipe comprising a first end and a second end, wherein the first end of the heat pipe is coupled to a heat pipe mating surface

a luminaire housing, wherein an inner surface of the luminaire housing comprises a housing mating surface, and wherein the heat pipe mating surface is configured to contact and releasably mate with the housing mating surface to define a thermal junction;

a luminaire base, wherein the luminaire base is coupled to the second end of the heat pipe and coupled to the luminaire housing, wherein the first end and the second end of the heat pipe are enclosed by the coupled luminaire housing luminaire base; and

an external heat sink provided on an outer surface of the luminaire housing proximate the housing mating surface.

20. The apparatus of claim 19, further comprising an LED driver connected to the thermal assembly.

21. The apparatus of claim 19, wherein the at least one light emitting diode comprises an individual LED, an LED chip, or an LED die mounted to a printed circuit board that is attached to the contact pad.

22. The apparatus of claim 19, further comprising a spring loaded member for biasing the heat pipe mating surface towards the housing mating surface.

23. The apparatus of claim 19, wherein the thermal assembly comprises the heat pipe and the contact pad integrated as single structure.

24. An apparatus comprising:

an LED module assembly comprising;

a thermal assembly comprising a heat pipe and a contact pad coupled to an exterior surface of the heat pipe;

at least one light emitting diode comprising a front side, a back side, and an electrical contact area, wherein the back side of the at least one light emitting diode is coupled directly to the contact pad;

a groove formed on a surface of the contact pad substantially parallel and opposite the electrical contact area to prevent contact between the electrical contact area and the contact pad at the groove;

a printed circuit board coupled to the front side of the at least one light emitting diode; and

the heat pipe comprising a first end and a second end, wherein the first end of the heat pipe is coupled to a heat pipe mating surface;

a luminaire housing, wherein an inner surface of the luminaire housing comprises a housing mating surface, and wherein the heat pipe mating surface is configured to contact and releasably mate with the housing mating surface to define a thermal junction;

a luminaire base, wherein the luminaire base is coupled to the second end of the heat pipe and coupled to the luminaire housing, wherein the first end and the second end of the heat pipe are enclosed by the coupled luminaire housing and the luminaire base; and

an external heat sink provided on an outer surface of the luminaire housing proximate the housing mating surface.

25. The apparatus of claim 24, further comprising a spring loaded member for biasing the heat pipe mating surface towards the housing mating surface.