LED light source utilizing magnetic attachment

• US 8,227,813 B2
• Filed: 09/22/2010
• Issued: 07/24/2012
• Est. Priority Date: 09/22/2010
• Status: Active Grant

• Current Assignee: Bridgelux Incorporated
• Original Assignee: Bridgelux Incorporated
• Inventors: Ward, Calvin B.
• Primary Examiner(s): Le, Tung X
• Application Number:
  US12/888,153
• Publication Number:
  US 20120068621A1
• Time in Patent Office: 671 Days
• Field of Search: 362/234, 362/253, 362/276, 362/295, 362/249.02, 362/249.04, 362/800, 362/802, 257/79, 257/88, 257/99, 257/678, 257/680, 257/701, 257/706
• US Class Current: 257/79
• CPC Class Codes: F21V 21/096 Magnetic devices
• CPC Class Codes: F21Y 2103/10 comprising a linear array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H05B 45/345 Current stabilisation; Maintaining constant current
• CPC Class Codes: H05B 45/3578 Emulating the electrical or functional characteristics of discharge lamps

Abstract

A light module and method for using the same are disclosed. The light module includes a heat-conducting structure and a plurality of LEDs bonded to a heat-conducting structure. The LEDs are bonded to a first surface of the heat-conducting structure and are mounted on the heat-conducting structure such that at least 50 percent of the heat generated by the LEDs is transferred to the heat-conducting structure. The heat-conducting structure includes a ferromagnetic material and is structured such that the heat-conducting structure bonds magnetically to a heat-dissipating structure with sufficient force to support the light module during the normal operation thereof when the light source is placed against the heat-dissipating structure. The present invention can be utilized for retrofitting an existing light fixture having an enclosure that includes a ferromagnetic material and a plurality of legacy light sources.

Claims

1. A light module comprising:

a heat-conducting structure; and

a plurality of LEDs bonded to a first surface of said heat-conducting structure, said LEDs generating heat when powered, said LEDs being mounted on said heat-conducting structure such that at least 50 percent of the heat generated by said LEDs is transferred to said heat-conducting structure, said heat-conducting structure comprising a ferromagnetic material and being structured such that said heat-conducting structure bonds magnetically to a heat-dissipating structure with sufficient force to support said light module during the normal operation thereof.

2. The light module of claim 1 wherein said ferromagnetic material is magnetized.

3. The light module of claim 1 further comprising an insulating layer overlying portions of said first surface and an electrical conductor deposited on said insulating layer, at least one of said LEDs being connected to said electrical conductor and powered therefrom.

4. The light module of claim 1 wherein said heat-conducting structure is part of a metal clad printed circuit board.

5. The light module of claim 1 wherein said ferromagnetic material comprises iron or nickel.

6. A method for retro-fitting an existing light fixture having an enclosure comprising a ferromagnetic material and plurality of legacy light sources, at least one of said legacy light sources being powered through a connector, said method comprising:

replacing at least one of said legacy light sources with an LED-based light module, said LED-based light module comprising;

a heat-conducting substrate; and

a plurality of LEDs directly bonded to a first surface of said heat-conducting substrate such that heat generated by said LEDs is directly transferred to said heat-conducting substrate, wherein said heat-conducting substrate comprises a second surface comprising a ferromagnetic material;

magnetically attaching said LED-based light module to said enclosure; and

powering said LED-based light module from said connector.

7. The method of claim 6 wherein said ferromagnetic material in said LED-based light source is magnetized.

8. The method of claim 6 wherein said magnetically attaching said LED-based light module to said enclosure comprises providing a layer of magnetized material between said enclosure and said LED-based light module.

9. The method of claim 6 wherein said LEDs generate heat and said second surface has an area sufficient to transfer at least 50 percent of said heat to said enclosure without causing said LEDs to operate at a temperature greater than 100°

C.

10. The method of claim 9 wherein said second surface has an area sufficient to transfer at least 50 percent of said heat to said enclosure without causing said LEDs to operate at a temperature greater than 70°

C.

11. The method of claim 6 wherein powering said LED-based module comprises providing a power supply that is separate from said LED-based light module, said power supply being connected to said connector and said LED-based module.

12. The method of claim 11 wherein said power supply is magnetically attached to said enclosure.

13. A luminaire comprising:

a heat-dissipating structure comprising a first ferromagnetic material; and

an LED-based module, said LED-based module comprising;

a heat-conducting substrate; and

a plurality of LEDs directly bonded to a first surface of said heat-conducting substrate such that heat generated by said LEDs is directly transferred to said heat-conducting substrate, wherein said heat-conducting substrate comprises a second surface comprising a second ferromagnetic material, wherein one of said first and second ferromagnetic materials is magnetized and wherein said heat-dissipating structure and said heat-conducting substrate are bound together by a magnetic field provided by said magnetized ferromagnetic material.

14. The luminaire of claim 13 wherein said heat-dissipating structure comprises an enclosure that surrounds said LED-based module.

15. The luminaire of claim 13 further comprising a power supply that converts AC power to DC power that powers said LED-based module, said power supply comprising a ferromagnetic material that causes said power supply to be magnetically bound to said heat-dissipating structure.

16. The luminaire of claim 13 wherein said LEDs generate heat and said second surface has an area sufficient to transfer at least 50 percent of said heat to said heat-dissipating structure without causing said LEDs to operate at a temperature greater than 100°

C.

17. The luminaire of claim 16 wherein said LEDs generate heat and said second surface has an area sufficient to transfer at least 50 percent of said heat to said heat-dissipating structure without causing said LEDs to operate at a temperature greater than 70°

C.

18. The luminaire of claim 13 wherein said magnetized ferromagnetic material comprises a separate layer of magnetized material that is bound to both said heat-dissipating structure and said second surface of said heat-conducting substrate.