LED lamp with active cooling element

• US 8,931,933 B2
• Filed: 02/07/2011
• Issued: 01/13/2015
• Est. Priority Date: 03/03/2010
• Status: Active Grant

• Current Assignee: IDEAL Industries Lighting, LLC (Ideal Industries Incorporated)
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Tong, Tao, Youmans, Mark, He, Yejin
• Primary Examiner(s): Mai, Anh
• Assistant Examiner(s): FAROKHROOZ, FATIMA N
• Application Number:
  US13/022,490
• Publication Number:
  US 20110215698A1
• Time in Patent Office: 1,436 Days
• Field of Search: 362/480, 362/546, 362/547, 362/218, 362/294, 362/555, 362/249.01, 362/249.02, 362/367, 362373-375, 362/368, 362/240, 362/362, 313/20, 313/45, 313/46, 439/487, 257/81
• US Class Current: 362/373
• CPC Class Codes: F21K 9/232 specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb
• CPC Class Codes: F21K 9/62 using mixing chambers, e.g. housings with reflective walls
• CPC Class Codes: F21K 9/64 using wavelength conversion means distinct or spaced from the light-generating element, e.g. a remote phosphor layer
• CPC Class Codes: F21V 29/63 using electrically-powered vibrating means; using ionic wind
• CPC Class Codes: F21V 29/67 characterised by the arrangement of fans
• CPC Class Codes: F21V 29/673 the fans being used for intake
• CPC Class Codes: F21V 29/677 the fans being used for discharging
• CPC Class Codes: F21V 29/773 the planes containing the fins or blades having the direction of the light emitting axis
• CPC Class Codes: F21V 3/02 characterised by the shape
• CPC Class Codes: F21V 3/12 the coatings comprising photoluminescent substances
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

Solid state lamp or bulb structures are disclosed that can provide an essentially omnidirectional emission pattern from directional emitting light sources, such as forward emitting light sources. The present invention is also directed to lamp structures using active elements to assist in thermal management of the lamp structures and in some embodiments to reduce the convective thermal resistance around certain of the lamp elements to increase the natural heat convection away from the lamp. Some embodiments include integral fans or other active elements such as diaphragm-pump type active cooling elements, that move air over the surfaces of a heat sink, while other embodiments comprise internal fans or other active elements that can draw air internal to the lamp. The movement of the air over these surfaces can agitate otherwise stagnant air to decrease the convective thermal resistance and increasing the ability of the lamp to dissipate heat generated during operation.

Claims

1. A solid state light source, comprising:

a light emitting diode (LED);

a heat sink with said LED in thermal contact with said heat sink; and

an integral diaphragm pump type cooling element comprising a housing and a plurality of top air holes and bottom air holes, wherein each of said plurality of top air holes is aligned with a respective one of said plurality of bottom air holes to reduce the convective thermal resistance of at least some of the light source elements;

wherein said integral diaphragm pump type cooling element is internal to a component of said light source and draws ambient air internal to said light source.

2. The light source of claim 1, wherein said integral diaphragm pump type cooling element is adjacent to said heat sink.

3. The light source of claim 1, wherein said integral diaphragm pump type cooling element flows air over one or more surface of said heat sink.

4. The light source of claim 1, wherein said integral diaphragm pump type cooling element reduces convective thermal resistance by agitating the air over at least some of said light source components.

5. The light source of claim 1, further comprising a diffuser dome over on said heat sink and over said LED.

6. The light source of claim 5, wherein said integral diaphragm pump type cooling element is internal to said heat sink and draws air into said heat sink and flows air into said diffuser dome.

7. The light source of claim 1, further comprising a phosphor carrier arranged so that at least some of light from said LED passes through said phosphor carrier.

8. The light source of claim 7, wherein said phosphor carrier is a three-dimensional structure.

9. The light source of claim 1, wherein said integral diaphragm pump type cooling element is modular.

10. The light source of claim 1, further comprising a base for connecting to a source of electrical power.

11. The light source of claim 10, further comprising drive electronics integral to said base.

12. The light source of claim 10, wherein said integral diaphragm pump type cooling element is between said base and said heat sink.

13. The light source of claim 5, wherein said diffuser dome disperses light from said LED.

14. A solid state lamp, comprising:

a plurality of light emitting diodes (LEDs);

a heat sink in relation to said LEDs so that said LEDs are in thermal contact with said heat sink; and

a diaphragm positive displacement pump cooling element integral to said lamp comprising a housing and a plurality of top air holes and bottom air holes, wherein each of said plurality of top air holes is aligned with a respective one of said plurality of bottom air holes to flow air over surfaces of said lamp to reduce the convective thermal resistance at said surfaces;

wherein said diaphragm positive displacement pump cooling element is internal to said heat sink.

15. The lamp of claim 14, wherein said diaphragm positive displacement pump cooling element draws air from external to the internal of said heat sink.

16. The lamp of claim 14, further comprising a diffuser cavity over said LEDs, said diaphragm positive displacement pump cooling element arranged to flow air into said diffuser cavity.

17. The lamp of claim 14, wherein said heat sink comprises heat sink fins, said diaphragm positive displacement pump cooling element moving air over and between said heat sink fins.

18. The lamp of claim 16, further comprising an outlet to allow air to exit from said diffuser cavity.

19. The lamp of claim 16, further comprising a phosphor carrier in said diffuser cavity over said LEDs.

20. The lamp of claim 19, wherein said phosphor carrier is three-dimensional and said diaphragm positive displacement pump cooling element flows air into said phosphor carrier.

21. The lamp of claim 14, further comprising a base for connecting to a source of electrical power.

22. The lamp of claim 21, wherein said base is at least partially internal to said heat sink.

23. The lamp of claim 22, wherein said diaphragm positive displacement pump cooling element flows air over said base.

24. A solid state lamp, comprising:

a light emitting diode (LED);

a heat sink in relation to said LED so that said LED is in thermal contact with said heat sink;

an active cooling element integral to said solid state lamp to flow air over surfaces of said solid state lamp to reduce the convective thermal resistance at said surfaces, wherein said solid state lamp emits light with a substantially omnidirectional emission pattern; and

wherein said active cooling element comprises a diaphragm pump type cooling element comprising a housing and a plurality of top air holes and bottom air holes, wherein each of said plurality of top air holes is aligned with a respective one of said plurality of bottom air holes.

25. The solid state lamp of claim 24, wherein said emission pattern is in compliance with Energy Star defined omnidirectional emission criteria.

26. The solid state lamp of claim 24, sized to fit within the A19 size envelope.

27. A solid state lamp, comprising:

a plurality of light emitting diodes (LEDs);

an active cooling element integral to said solid state lamp to flow air over surfaces of said solid state lamp comprising an emission pattern that complies with Energy Star defined omnidirectional emission criteria, and wherein said solid state lamp is sized to fit the A19 size envelope; and

wherein said active cooling element comprises a diaphragm pump type cooling element comprising a housing and a plurality of top air holes and bottom air holes, wherein each of said plurality of top air holes is aligned with a respective one of said plurality of bottom air holes.