LED illuminating device and light engine thereof

• US 8,007,143 B2
• Filed: 06/03/2009
• Issued: 08/30/2011
• Est. Priority Date: 03/05/2009
• Status: Expired due to Fees

• Current Assignee: Foxconn Technology Co., Ltd.
• Original Assignee: Foxconn Technology Co., Ltd.
• Inventors: Liu, Tay-Jian
• Primary Examiner(s): Husar; Stephen F
• Assistant Examiner(s): CRANSON JR, JAMES W
• Application Number:
  US12/477,901
• Publication Number:
  US 20100225217A1
• Time in Patent Office: 818 Days
• Field of Search: 362/218, 362/249.02, 362/294, 362/267, 362/373
• US Class Current: 362/373
• CPC Class Codes: F21K 9/23 Retrofit light sources for lighting devices with a single fitting for each light source, e.g. for substitution of incandescent lamps with bayonet or threaded fittings
• CPC Class Codes: F21K 9/238 Arrangement or mounting of circuit elements integrated in the light source
• CPC Class Codes: F21V 23/006 the substrate being distinct from the light source holder
• CPC Class Codes: F21V 23/007 enclosed in a casing
• CPC Class Codes: F21V 29/51 using condensation or evaporation of a fluid, e.g. heat pipes
• 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 29/71 using a combination of separate elements interconnected by heat-conducting means, e.g. with heat pipes or thermally conductive bars between separate heat-sink elements
• CPC Class Codes: F21V 29/74 with fins or blades
• 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 29/83 the elements having apertures, ducts or channels, e.g. heat radiation holes
• CPC Class Codes: F21V 29/89 Metals
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 23/427 Cooling by change of state, e.g. use of heat pipes by liquefied gas H01L23/445
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

An LED illuminating device includes an optical section, an electrical section, and a heat dissipation section. The heat dissipation section is provided with a loop heat exchange device. The loop heat exchange device includes a hollow metal base and a plurality of metal fins extending outwardly from the metal base. A hermetical chamber is defined in the metal base. The chamber is cylindrical and has a U-shaped cross section along an axial direction of the metal base. A wick structure is attached to an inner surface of the chamber. A working fluid is saturated in the wick structure. A light source is thermally attached to the metal base.

Claims

1. An LED illuminating device, comprising:

an optical section being provided with a light source therein;

an electrical section being electrically connected with the light source; and

a heat dissipation section located between the optical section and the electrical section, the heat dissipation section being provided with a loop heat exchange device, the loop heat exchange device comprising a hollow metal base and a plurality of metal fins extending outwardly from the hollow metal base, a hermetical chamber being defined in the hollow metal base, the hermetical chamber being cylindrical and having a U-shaped cross section along an axial direction of the hollow metal base, a wick structure being attached to an inner surface of the hermetical chamber, a working fluid being saturated in the wick structure, the light source being thermally attached to the hollow metal base.

2. The LED illuminating device of claim 1, wherein the hollow metal base comprises an inner metal tube and an outer metal tube, the outer metal tube has a diameter greater than the inner metal tube, the inner metal tube is coaxially received in the outer metal tube with a first gap defined between an inner circumferential surface of the outer metal tube and an outer circumferential surface of the inner metal tube, the first gap extends axially along the axial direction of the hollow metal base, and the metal fins extend radially outwardly from an outer circumferential surface of the outer metal tube.

3. The LED illuminating device of claim 2, wherein the hollow metal base further comprises a heat-absorbing plate, a circular cover plate and an annular cover plate, the heat-absorbing plate hermetically seals a bottom of the outer metal tube, the circular cover plate hermetically seals a bottom of the inner metal tube, a second gap is defined between the circular cover plate and the heat-absorbing plate, the second gap communicates with a bottom of the first gap, the annular cover plate hermetically seals a top of the first gap, the hermetical chamber is cooperatively formed by the first gap and the second gap in the hollow metal base, and the light source is attached to the heat-absorbing plate.

4. The LED illuminating device of claim 3, wherein a top of the inner metal tube facing the electrical section is open, a blind hole is axially defined in the inner metal tube, and the blind hole is enclosed by an inner circumferential surface of the inner metal tube and communicates with an outer environment.

5. The LED illuminating device of claim 4, wherein a plurality of metal fins extends radially inwardly from the inner circumferential surface of the inner metal tube into the blind hole.

6. The LED illuminating device of claim 4, wherein the electrical section comprises a casing, a plurality of air passage holes are provided through a circumferential periphery of the casing, a circuit board is received in the blind hole of the inner metal tube, and the light source is electrically connected with the circuit board.

7. The LED illuminating device of claim 3, wherein a plurality of metal fins extends upwardly from a top surface of the annular cover plate.

8. The LED illuminating device of claim 3, wherein the wick structure comprises a first porous wick attached to an inner surface of the heat-absorbing plate, a second porous wick attached to an inner surface of the circular cover plate, a third porous wick attached to an inner surface of the annular cover plate, a fourth porous wick attached to the outer circumferential surface of the inner metal tube, and a fifth porous wick attached to the inner circumferential surface of the outer metal tube, two ends of the fourth wick connect respectively with the second wick and the third wick, and two ends of the fifth wick connect respectively with the first wick and the third wick.

9. The LED illuminating device of claim 8, wherein the first wick and the second wick are connected together by a sixth wick therebetween.

10. The LED illuminating device of claim 3, wherein the electrical section comprises a casing and a circuit board received in the casing, a plurality of air passage holes are provided through a circumferential periphery of the casing, and the light source is electrically connected with the circuit board.

11. The LED illuminating device of claim 3, wherein a cooling fan is provided over the loop heat exchange device and configured to generate an airflow through the loop heat exchange device, and the cooling fan is located between the loop heat exchange device and the electrical section.

12. The LED illuminating device of claim 11, wherein a spacer is provided between the cooling fan and the electrical section, a plurality of air passage openings are defined radially through a circumferential periphery of the spacer, and the airflow flows through the air passage openings of the spacer.

13. A light engine of an LED illuminating device, comprising:

a light source; and

a loop heat exchange device comprising a hollow metal base and a plurality of metal fins extending outwardly from the hollow metal base, a hermetical chamber being defined in the hollow metal base, the hermetical chamber comprising an annular first gap at a top side thereof and a second gap at a bottom side thereof and communicating with a bottom of the first gap, the first gap extending upwardly from a periphery of the second gap, a wick structure being attached to an inner surface of the hermetical chamber, a working fluid being saturated in the wick structure, the light source being thermally attached to a bottom of the hollow metal base.

14. The light engine of the LED illuminating device of claim 13, wherein the hollow metal base comprises an inner metal tube and an outer metal tube, the outer metal tube has a diameter greater than the inner metal tube, the inner metal tube is coaxially received in the outer metal tube, the first gap being defined between an inner circumferential surface of the outer metal tube and an outer circumferential surface of the inner metal tube, and the metal fins extend radially outwardly from an outer circumferential surface of the outer metal tube.

15. The light engine of the LED illuminating device of claim 14, wherein the hollow metal base further comprises a heat-absorbing plate, a circular cover plate and an annular cover plate, the heat-absorbing plate hermetically seals a bottom of the outer metal tube, the circular cover plate hermetically seals a bottom of the inner metal tube, the second gap is defined between the circular cover plate and the heat-absorbing plate, the annular cover plate hermetically seals a top of the first gap, and the light source is attached to the heat-absorbing plate.

16. The light engine of the LED illuminating device of claim 15, wherein a top of the inner metal tube is open, a blind hole is axially defined in the inner metal tube, the blind hole is enclosed by an inner circumferential surface of the inner metal tube and communicates with an outer environment.

17. The light engine of the LED illuminating device of claim 16, wherein a plurality of metal fins extends radially inwardly from the inner circumferential surface of the inner metal tube into the blind hole.

18. The light engine of the LED illuminating device of claim 15, wherein a plurality of metal fins extends upwardly from a top surface of the annular cover plate.

19. The light engine of the LED illuminating device of claim 15, wherein the wick structure comprises a first porous wick attached to an inner surface of the heat-absorbing plate, a second porous wick attached to an inner surface of the circular cover plate, a third porous wick attached to an inner surface of the annular cover plate, a fourth porous wick attached to the outer circumferential surface of the inner metal tube, and a fifth porous wick attached to the inner circumferential surface of the outer metal tube, two ends of the fourth wick connect respectively with the second wick and the third wick, two ends of the fifth wick connect respectively with the first wick and the third wick.

20. The light engine of the LED illuminating device of claim 19, wherein the first wick and the second wick are connected together by a sixth wick therebetween.