Lighting device with reverse tapered heatsink

• US 8,227,961 B2
• Filed: 06/04/2010
• Issued: 07/24/2012
• Est. Priority Date: 06/04/2010
• Status: Active Grant

• Current Assignee: IDEAL Industries Lighting, LLC (Ideal Industries Incorporated)
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: van de Ven, Antony Paul
• Primary Examiner(s): Patel, Vip
• Application Number:
  US12/794,559
• Publication Number:
  US 20110298350A1
• Time in Patent Office: 781 Days
• Field of Search: 313/46, 313/498, 313/512
• US Class Current: 313/46
• CPC Class Codes: F21K 9/232 specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb
• CPC Class Codes: F21V 29/51 using condensation or evaporation of a fluid, e.g. heat pipes
• CPC Class Codes: F21V 29/74 with fins or blades
• CPC Class Codes: F21V 29/78 with helically or spirally arranged fins or blades
• CPC Class Codes: F21V 29/80 with pins or wires
• CPC Class Codes: F21V 3/00 Globes; Bowls; Cover glasses with refracting properties F21V5/00; with reflecting properties F21V7/00; characterised by cooling arrangements F21V29/506
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

A solid state lighting devices includes a heatsink having a first end arranged proximate to a base end, and a second end arranged between the first end and a solid state emitter, wherein at least a portion of the heatsink is wider at point intermediate the first end and the second end than the width of the heatsink at the second end. Such reverse angled heatsink reduces obstruction of light. A heatsink may include multiple fins and a heatpipe.

Claims

1. A solid state lighting device comprising:

a base end;

at least one solid state emitter; and

a heatsink disposed between the base end and the at least one solid state emitter, and arranged to dissipate heat generated by the at least one solid state emitter;

wherein;

the heatsink has a first end proximate to the base end, and has a first width at the first end;

the heatsink has a second end disposed between the base end and the at least one solid state emitter, and has a second width at the second end; and

at least a portion of the heatsink disposed between the first end and the second end has a third width that is greater than the second width.

2. The solid state lighting device of claim 1, wherein the base end comprises at least one electrical contact.

3. The solid state lighting device of claim 1, wherein the at least one solid state emitter is disposed under or within a cover.

4. The solid state lighting device of claim 3, wherein the cover comprises a diffuser arranged to diffuse light emitted by the at least one solid state emitter.

5. The solid state lighting device of claim 3, wherein the cover is arranged as a substantially spherical or semi-spherical globe.

6. The solid state lighting device of claim 1, having a substantially central axis extending in a direction between the base end and an emitter mounting area, wherein the heatsink is arranged to permit unobstructed emission of light generated by the at least one solid state emitter according to each emission half-angle of greater than 90 degrees relative to the substantially central axis around an entire lateral perimeter of the solid state lighting device.

7. The solid state lighting device of claim 1, having a substantially central axis extending in a direction between the base end and an emitter mounting area, wherein the heatsink is arranged to permit unobstructed emission of light generated by the at least one solid state emitter according to each emission half-angle of at least about 120 degrees relative to the substantially central axis around an entire lateral perimeter of the solid state lighting device.

8. The solid state lighting device of claim 1, having a substantially central axis extending in a direction between the base end and an emitter mounting area, wherein the heatsink is arranged to permit unobstructed emission of light generated by the at least one solid state emitter according to each emission half-angle of at least about 135 degrees relative to the substantially central axis around an entire lateral perimeter of the solid state lighting device.

9. The solid state lighting device of claim 1, having a substantially central axis extending in a direction between the base end and an emitter mounting area, wherein the heatsink provides an asymmetrical optical obstruction profile relative to the substantially central axis.

10. The solid state lighting device of claim 1, wherein the heatsink comprises a plurality of fins.

11. The solid state lighting device of claim 10, wherein the plurality of fins includes fins arranged as outwardly-protruding pins or rods.

12. The solid state lighting device of claim 10, wherein the plurality of fins includes fins arranged substantially parallel to a substantially central axis defined through the base end and an emitter mounting area.

13. The solid state lighting device of claim 10, wherein the plurality of fins includes fins arranged substantially perpendicular to a substantially central axis defined through the base end and an emitter mounting area.

14. The solid state lighting device of claim 1, wherein the heatsink comprises at least one fin arranged in a spiral shape.

15. The solid state lighting device of claim 1, wherein the heatsink comprises a heatpipe.

16. The solid state lighting device of claim 1, wherein the heatsink is adapted to dissipate a steady state thermal load of at least about 2 watts in an ambient air environment of about 35°

C. while maintaining a junction temperature of the at least one solid state emitter at or below about 85°

C.

17. The solid state lighting device of claim 1, comprising any of a plurality of electrical conductors and a plurality of electrical circuit elements disposed within the heatsink.

18. The solid state lighting device of claim 1, being sized and shaped in accordance with ANSI Standard C.78.20-2003 for A19 bulbs.

19. A lamp or light fixture comprising the solid state lighting device of claim 1.

20. A solid state lighting device comprising:

a base end;

at least one solid state emitter; and

a heatsink disposed between the base and the at least one solid state emitter, and arranged to dissipate heat generated by the at least one solid state emitter;

wherein the lighting device has a substantially central axis extending in a direction between the base end and an emitter mounting area in which the at least one solid state emitter is mounted;

wherein the heatsink is arranged to permit unobstructed emission of light generated by the at least one solid state emitter according to each emission half-angle of greater than 90 degrees relative to the central axis around an entire lateral perimeter of the solid state lighting device.

21. The solid state lighting device of claim 20, wherein the heatsink is arranged to permit unobstructed emission of light generated by the at least one solid state emitter according to each emission half-angle of at least about 120 degrees relative to the central axis around an entire lateral perimeter of the solid state lighting device.

22. The solid state lighting device of claim 20, wherein the heatsink is arranged to permit unobstructed emission of light generated by the at least one solid state emitter according to each emission half-angle of at least about 135 degrees relative to the central axis around an entire lateral perimeter of the solid state lighting device.

23. The solid state lighting device of claim 20, wherein the at least one solid state emitter is disposed under or within a cover.

24. The solid state lighting device of claim 20, wherein the base end comprises at least one electrical contact.

25. The solid state lighting device of claim 20, wherein the heatsink comprises a plurality of fins.

26. The solid state lighting device of claim 25, wherein the plurality of fins includes fins arranged as outwardly-protruding pins or rods.

27. The solid state lighting device of claim 25, wherein the plurality of fins includes fins arranged substantially parallel to a substantially central axis defined through the base end and an emitter mounting area.

28. The solid state lighting device of claim 25, wherein the plurality of fins includes fins arranged substantially perpendicular to a substantially central axis defined through the base end and an emitter mounting area.

29. The solid state lighting device of claim 20, wherein the heatsink comprises at least one fin arranged in a spiral shape.

30. The solid state lighting device of claim 20, wherein the heatsink comprises a heatpipe.

31. The solid state lighting device of claim 20, wherein the heatsink comprises a plurality of fins in conductive thermal communication with the heatpipe.

32. The solid state lighting device of claim 20, wherein the heatsink is adapted to dissipate a steady state thermal load of at least about 2 watts in an ambient air environment of about 35°

C. while maintaining a junction temperature of the at least one solid state emitter at or below about 85°

C.

33. The solid state lighting device of claim 20, comprising any of a plurality of electrical conductors and a plurality of electrical circuit elements disposed within the heatsink.

34. The solid state lighting device of claim 20, being sized and shaped in accordance with ANSI Standard C.78.20-2003 for A19 bulbs.

35. A lamp or light fixture comprising the solid state lighting device of claim 20.