Flashlight providing thermal protection for electronic elements thereof

• US 20070236920A1
• Filed: 03/31/2006
• Published: 10/11/2007
• Est. Priority Date: 03/31/2006
• Status: Active Grant

• Current Assignee: Streamlight, Inc.
• Original Assignee: Streamlight, Inc.
• Inventors: Snyder, Mark
• Granted Patent: US 7,357,534 B2
• Time in Patent Office: Days
• US Class Current: 362/157
• CPC Class Codes: F21L 4/027 the light sources being a LED
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 29/89 Metals
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

A portable light including thermal protection comprises a thermally-conductive heat sink having a heat dissipating part and a heat collecting part; a light source having a surface thermally coupled to the heat collecting part of the heat sink; an electronic circuit for controlling the light source, wherein the electronic circuit is adjacent the heat collecting portion of the heat sink; and a thermally-conductive material between the electronic circuit and the heat collecting part of the heat sink for providing a thermally conductive path therebetween.

Claims

1. A portable light including thermal protection comprising:

a cup-shaped thermally-conductive heat sink having a wall and a closed end defining a central cavity, the closed end having first and second opposing surfaces;

a light-emitting diode having a surface adapted for conducting heat to a heat sink, wherein the surface of said light emitting diode is in thermal contact with the first surface of the closed end of said heat sink;

an electronic circuit for controlling a voltage, a current, or a voltage and a current, applied to said light-emitting diode, wherein said electronic circuit is adjacent the second surface of the closed end of said heat sink; and

a thermally-conductive material filling between said electronic circuit and the second surface of said heat sink for providing a thermally conductive path therebetween,

whereby said light-emitting diode and said electronic circuit are thermally coupled to said heat sink.

2. The portable light of claim 1 wherein said light-emitting diode is disposed in the central cavity of said heat sink abutting the first surface of the closed end thereof.

3. The portable light of claim 1 wherein said electronic circuit receives a battery voltage and current and provides a voltage and current for energizing said light-emitting diode.

4. The portable light of claim 1 wherein said thermally-conductive material includes a thermally-conductive epoxy, a thermally-conductive silicone, a thermally-conductive thermoplastic material, or any combination thereof.

5. The portable light of claim 1 further comprising a reflector having an opening for receiving a source of light, wherein said light-emitting diode is positioned in the opening of said reflector for producing light in said reflector.

6. The portable light of claim 5 further comprising a portable light housing to which said heat sink is attached, wherein the wall of said heat sink provides a part of an exterior surface of or adjacent to said portable light housing.

7. The portable light of claim 5 wherein said reflector is of a thermally conductive material and has a surface complementary to the wall of said heat sink, and wherein the wall of said heat sink and the complementary surface of said reflector are substantially in thermal contact.

8. The portable light of claim 1 further comprising a portable light housing to which said heat sink is attached, wherein the wall of said heat sink provides a part of an exterior surface of or adjacent to said portable light housing.

9. The portable light of claim 8 wherein said portable light housing has a cavity for receiving a battery and wherein said electronic circuit includes one or more terminals adapted for providing an electrical connection in the battery cavity of said portable light housing.

36. The portable light of claim 1 further comprising:

a housing supporting said electronic circuit adjacent the second surface of the closed end of said heat sink,

wherein the second surface of the closed end of said heat sink, said electronic circuit and said housing define a cavity that is substantially filled with said thermally-conductive material.

10. A portable light including thermal protection comprising:

a cup-shaped thermally-conductive heat sink having a central cavity and a fundus;

a solid state light source having a surface adapted for conducting heat to a heat sink, wherein the surface of said solid state light source is in thermal contact with the fundus of said heat sink;

an electronic circuit for controlling a voltage, a current, or a voltage and a current, applied to said solid state light source, wherein said electronic circuit is adjacent the fundus of said heat sink; and

a thermally-conductive material filling between said electronic circuit and the fundus of said heat sink for providing a thermally conductive path therebetween,

whereby said solid state light source and said electronic circuit are thermally coupled to said heat sink.

11. The portable light of claim 10 wherein said solid state light source is disposed in the central cavity of said heat sink abutting the fundus thereof.

12. The portable light of claim 10 wherein said electronic circuit receives a battery voltage and current and provides a voltage and current for energizing said solid state light source.

13. The portable light of claim 10 wherein said thermally-conductive material includes a thermally-conductive epoxy, a thermally-conductive silicone, a thermally-conductive thermoplastic material, or any combination thereof.

14. The portable light of claim 10 further comprising a reflector having an opening for receiving a source of light, wherein said solid state light source is positioned in the opening of said reflector for producing light in said reflector.

15. The portable light of claim 14 further comprising a portable light housing to which said heat sink is attached, wherein said heat sink is at least partly exposed exterior to said portable light housing.

16. The portable light of claim 14 wherein said reflector is of a thermally conductive material and has a surface complementary to said heat sink, and wherein said heat sink and the complementary surface of said reflector are substantially in thermal contact.

17. The portable light of claim 10 further comprising a portable light housing to which said heat sink is attached, wherein said heat sink is at least partly exposed exterior to said portable light housing.

18. The portable light of claim 17 wherein said portable light housing has a battery cavity and wherein said electronic circuit includes a terminal providing an electrical connection in the battery cavity of said portable light housing.

37. The portable light of claim 10 further comprising:

a housing supporting said electronic circuit adjacent the fundus of said heat sink,

wherein the fundus of said heat sink, said electronic circuit and said housing define a cavity that is substantially filled with said thermally-conductive material.

19. A portable light including thermal protection comprising:

a thermally-conductive heat sink having a heat dissipating part and a heat collecting part;

a light source having a surface adapted for conducting heat to a heat sink, wherein the surface of said light source is thermally coupled to the heat collecting part of said heat sink;

an electronic circuit for controlling a voltage, a current, or a voltage and a current, applied to said light source;

a housing supporting said electronic circuit adjacent the heat collecting part of said heat sink, wherein the heat collecting part of said heat sink, said electronic circuit and said housing define a cavity therebetween; and

a thermally-conductive material substantially filling the cavity between said electronic circuit and the heat collecting part of said heat sink for providing a thermally conductive path therebetween,

whereby said light source and said electronic circuit are thermally coupled to said heat sink.

20. The portable light of claim 19 wherein said light source includes a light-emitting diode abutting the heat collecting part of said heat sink.

21. The portable light of claim 19 wherein said electronic circuit receives a battery voltage and current and provides a voltage and current for energizing said light source.

22. The portable light of claim 19 wherein said thermally-conductive material includes a thermally-conductive epoxy, a thermally-conductive silicone, a thermally-conductive thermoplastic material, or any combination thereof.

23. The portable light of claim 19 further comprising a reflector having an opening for receiving a source of light, wherein said light source is positioned in the opening of said reflector for producing light in said reflector.

24. The portable light of claim 23 further comprising a portable light housing to which said heat sink is attached, wherein the heat dissipating part of said heat sink is at least partly exposed exterior to said portable light housing.

25. The portable light of claim 23 wherein said reflector is of a thermally conductive material and has a surface complementary to said heat sink, and wherein said heat sink and the complementary surface of said reflector are thermally coupled.

26. The portable light of claim 19 further comprising a portable light housing to which said heat sink is attached, wherein the heat dissipating part of said heat sink is at least partly exposed exterior to said portable light housing.

27. The portable light of claim 26 wherein said portable light housing has a battery cavity and wherein said electronic circuit includes a terminal providing an electrical connection in the battery cavity of said portable light housing.

28. A flashlight including thermal protection comprising:

a cup-shaped thermally-conductive heat sink having a cylindrical wall and a circular closed end defining a central cavity, the circular closed end having interior and exterior opposing surfaces;

a light-emitting diode in the central cavity of said heat sink and having a surface adapted for conducting heat to a heat sink, wherein the heat conducting surface of said light emitting diode is in thermal contact abutting the interior surface of the circular closed end of said heat sink;

a circuit board including an electronic circuit for controlling a voltage, a current, or a voltage and a current, applied to said light-emitting diode;

a housing supporting said electronic circuit board adjacent the exterior surface of the circular closed end of said heat sink;

wherein the exterior surface of the circular closed end of said heat sink, the electronic circuit board and the housing define a cavity therebetween; and

a thermally-conductive material substantially filling the cavity defined between said heat sink, said electronic circuit board and said housing for providing a thermally conductive path between said electronic circuit board and said heat sink,

whereby said light-emitting diode and said electronic circuit board are thermally coupled to said heat sink.

29. The flashlight of claim 28 wherein said electronic circuit receives a battery voltage and current and provides a voltage and current for energizing said light-emitting diode.

30. The flashlight of claim 28 wherein said thermally-conductive material includes a thermally-conductive epoxy, a thermally-conductive silicone, a thermally-conductive thermoplastic material, or any combination thereof.

31. The flashlight of claim 28 further comprising a reflector having a curved light reflecting surface and having a central opening for receiving a source of light, wherein said light-emitting diode is positioned in the central opening of said reflector for producing light that is reflected by the light reflecting surface of said reflector.

32. The flashlight of claim 31 further comprising a flashlight housing to which said heat sink is attached, wherein the cylindrical wall of said heat sink provides an extension of an exterior cylindrical surface of said flashlight housing.

33. The flashlight of claim 31 wherein said reflector is of a thermally conductive material and has a cylindrical surface complementary to the cylindrical wall of said heat sink, and wherein the cylindrical wall of said heat sink and the complementary cylindrical surface of said reflector are substantially in thermal contact.

34. The flashlight of claim 28 further comprising a flashlight housing to which said heat sink is attached, wherein the cylindrical wall of said heat sink provides an extension of an exterior cylindrical surface of said flashlight housing.

35. The flashlight of claim 34 wherein said flashlight housing has a battery cavity for receiving a battery, and wherein said electronic circuit board includes one or more terminals adapted for providing an electrical connection to a battery in the battery cavity of said flashlight housing.