Multiple thermal path packaging for solid state light emitting apparatus and associated assembling methods

• US 20070262337A1
• Filed: 04/21/2006
• Published: 11/15/2007
• Est. Priority Date: 04/21/2006
• Status: Active Grant

• Current Assignee: IDEAL Industries Lighting, LLC (Ideal Industries Incorporated)
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Villard, Russell
• Granted Patent: US 7,625,103 B2
• Time in Patent Office: Days
• US Class Current: 257/99
• 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 29/503 of light sources cooling arrangements structurally associated with gas-discharge or vapour-discharge lamps H01J61/52; cooling arrangements structurally associated with electric incandescent lamps H01K1/58; cooling arrangements structurally associated with light-emitting diodes H01L33/64
• CPC Class Codes: F21V 29/74 with fins or blades
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 33/642 characterized by the shape

Abstract

A mounting substrate includes a peripheral portion and a central portion. Solid state light emitting elements are provided on the mounting substrate. A housing is configured to thermally couple to the peripheral portion of the mounting substrate, so as to provide a first thermal conduction path for at least some heat generated by the solid state light emitting elements. A thermal conduction member is configured to thermally couple the central portion of the mounting substrate to the housing, so as to provide a second thermal conduction path that is different from the first thermal conduction path, for at least some heat generated by the solid state light emitting elements. Related assembling methods are also described.

Claims

1. A light emitting apparatus comprising:

a mounting substrate that includes a peripheral portion and a central portion;

a plurality of solid state light emitting elements on the mounting substrate;

a housing that is configured to thermally couple to the peripheral portion of the mounting substrate so as to provide a first thermal conduction path for at least some heat generated by the solid state light emitting elements; and

a thermal conduction apparatus that is configured to thermally couple the central portion of the mounting substrate to the housing so as to provide a second thermal conduction path that is different than the first thermal conduction path for at least some heat generated by the solid state light emitting elements.

2. A light emitting apparatus according to claim 1 wherein the housing is configured to thermally couple to the peripheral portion of the mounting substrate at a first portion of the housing so as to provide the first thermal conduction path and wherein the thermal conduction apparatus is configured to thermally couple the central portion of the mounting substrate to a second portion of the housing that is spaced apart from the first portion to provide the second thermal conduction path.

3. A light emitting apparatus according to claim 1 wherein the housing is configured to thermally couple to the peripheral portion of the mounting substrate so as to provide the first thermal conduction path through the peripheral portion of the mounting substrate to the housing.

4. A light emitting apparatus according to claim 1 wherein the thermal conduction apparatus is a first thermal conduction apparatus, the light emitting apparatus further comprising a second thermal conduction apparatus that is configured to thermally couple the peripheral portion of the mounting substrate to the housing.

5. A light emitting apparatus according to claim 1 wherein the mounting substrate includes first and second opposing faces, wherein the solid state light emitting devices are on the first face and wherein the thermal conduction apparatus thermally couples the central portion of the second face to the housing.

6. A light emitting apparatus according to claim 4 wherein the mounting substrate includes first and second opposing faces, wherein the solid state light emitting devices are on the first face, wherein the first thermal conduction apparatus thermally couples the central portion of the second face to the housing and wherein the second thermal conduction apparatus thermally couples the peripheral portion of the second face to the housing.

7. A light emitting apparatus according to claim 6 wherein the second thermal conduction apparatus is a ring-shaped member including a face that is coupled to the peripheral portion of the second face of the mounting substrate and including an aperture therein, and wherein the first thermal conduction apparatus extends through the aperture to the central portion of the second face of the mounting substrate.

8. A light emitting apparatus according to claim 1 wherein the housing comprises a cylinder and wherein the mounting substrate comprises a disk that is mounted coaxially within the cylinder.

9. A light emitting apparatus according to claim 1 wherein the thermal conduction apparatus comprises at least one thermally conductive beam that extends between the central portion of the mounting substrate and the housing.

10. A light emitting apparatus according to claim 4 wherein the housing comprises a cylinder, wherein the mounting substrate comprises a disk, wherein the second thermal conduction apparatus comprises a ring-shaped member including a face that is coupled to a face of the mounting substrate at the peripheral portion and includes an aperture therein, and wherein the first thermal conduction apparatus comprises at least one thermally conductive beam that extends from the face of the mounting substrate at the central portion, through the aperture to the housing.

11. A light emitting apparatus according to claim 9 wherein the at least one thermally conductive beam is fixedly attached to both the mounting substrate and the housing.

12. A light emitting apparatus according to claim 9 wherein the at least one thermally conductive beam is fixedly attached to only one of the mounting substrate or the housing.

13. A light emitting apparatus according to claim 1 wherein the thermal conduction apparatus comprises a thermally conductive fibrous pad that extends between the central portion of the mounting substrate and the housing.

14. A light emitting apparatus according to claim 1 wherein the plurality of solid state light emitting elements comprise a plurality of light emitting diodes.

15. A light emitting apparatus comprising:

a cylindrical housing;

a disk-shaped mounting substrate that includes first and second opposing faces, each face including a peripheral portion and a central portion, and being mounted coaxially in the cylindrical housing;

a plurality of solid state light emitting elements on the peripheral and central portions of the first face of the mounting substrate; and

at least one thermally conductive member that extends from the central portion of the second face of the mounting substrate to the cylindrical housing remote from the second face.

16. A light emitting apparatus according to claim 15 wherein the at least one thermally conductive member is fixedly attached to the central portion of the second face of the mounting substrate and is fixedly attached to the cylindrical housing remote from the second face.

17. A light emitting apparatus according to claim 15 further comprising:

a ring-shaped thermally conductive member having a face that is coupled to the peripheral portion of the second face of the mounting substrate and including an aperture therein, and wherein the at least one thermally conductive member extends from the central portion of the second face of the mounting substrate, through the aperture and to the cylindrical housing remote from the second face.

18. A light emitting apparatus according to claim 15 wherein the at least one thermally conductive member comprises at least one thermally conductive beam that extends from the central portion of the second face of the mounting substrate to the cylindrical housing remote from the second face.

19. A light emitting apparatus according to claim 15 wherein the at least one thermally conductive member comprises a thermally conductive fibrous pad that extends from the central portion of the second face of the mounting substrate to the cylindrical housing remote from the second face.

20. A light emitting apparatus according to claim 15 wherein the plurality of solid state light emitting elements comprise a plurality of light emitting diodes.

21. A light emitting apparatus comprising:

a housing;

a mounting substrate in the housing;

a plurality of solid state light emitting elements on the mounting substrate; and

a thermal conduction apparatus that is configured to thermally couple the mounting substrate to the housing, remote from the mounting substrate.

22. A light emitting apparatus according to claim 21 wherein the mounting substrate includes first and second opposing faces, wherein the solid state light emitting devices are on the first face and wherein the thermal conduction apparatus thermally couples the second face to the housing, remote from the second face.

23. A light emitting apparatus according to claim 21 wherein the thermal conduction apparatus comprises at least one thermally conductive beam that extends between the mounting substrate and the housing, remote from the mounting substrate.

24. A light emitting apparatus according to claim 23 wherein the at least one thermally conductive beam is fixedly attached to both the mounting substrate and the housing.

25. A light emitting apparatus according to claim 23 wherein the at least one thermally conductive beam is fixedly attached to only one of the mounting substrate or the housing.

26. A light emitting apparatus according to claim 21 wherein the thermal conduction apparatus comprises a thermally conductive fibrous pad that extends between the mounting substrate and the housing, remote from the mounting substrate.

27. A light emitting apparatus according to claim 21 wherein the plurality of solid state light emitting elements comprise a plurality of light emitting diodes.

28. A method of assembling a light emitting apparatus that includes a housing and a mounting substrate that has a peripheral portion and a central portion, and a plurality of solid state light emitting elements on the mounting substrate, the method comprising:

inserting the mounting substrate into the housing; and

mounting at least one thermally conductive member in the housing to extend from the central portion of the mounting substrate to the housing remote from the mounting substrate.

29. A method according to claim 28 wherein mounting comprises mounting at least one thermally conductive beam in the housing to extend from the central portion of the mounting substrate to the housing remote from the mounting substrate.

30. A method according to claim 28 wherein mounting comprises mounting at least one thermally conductive fibrous pad in the housing to extend from the central portion of the mounting substrate to the housing remote from the mounting substrate.

31. A method according to claim 28 wherein the plurality of solid state light emitting elements comprise a plurality of light emitting diodes.