Thermal management of LED-based lighting systems

• US 7,806,574 B2
• Filed: 04/16/2007
• Issued: 10/05/2010
• Est. Priority Date: 04/16/2006
• Status: Expired due to Fees

• Current Assignee: Current Lighting Solutions, LLC (f/k/a GE Lighting Solutions, LLC) (American Industrial Partners)
• Original Assignee: Albeo Technologies (Savant Systems, LLC)
• Inventors: Bisberg, Jeff, Van Laanen, Peter
• Primary Examiner(s): O Shea; Sandra L
• Assistant Examiner(s): ALLEN, DANIELLE NICOLE
• Application Number:
  US11/735,903
• Publication Number:
  US 20070242462A1
• Time in Patent Office: 1,268 Days
• Field of Search: 362/800, 362/547, 362/218, 362/264, 362/294, 362/345, 362/373, 362/293
• US Class Current: 362/547
• CPC Class Codes: F21V 19/0055 by screwing
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 29/763 the planes containing the fins or blades having the direction of the light emitting axis
• CPC Class Codes: F21V 29/89 Metals
• 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 33/647 the elements conducting electric current to or from the semiconductor body
• CPC Class Codes: H05K 1/0203 Cooling of mounted components H05K1/0272 takes precedence
• CPC Class Codes: H05K 1/0209 External configuration of printed circuit board adapted for heat dissipation, e.g. lay-out of conductors, coatings
• CPC Class Codes: H05K 2201/10106 Light emitting diode [LED]
• CPC Class Codes: H05K 3/0061 onto a metallic substrate, e.g. a heat sink heat sinks for electric apparatus H05K7/20
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

An LED-based lighting system includes a printed circuit board (“PCB”) having conductors on a front-side thereof, one or more LEDs mounted with the conductors, and a structural element. The PCB is mounted with the conductors near to the structural element so that heat dissipation from the LEDs is primarily through the conductors and the structural element. A method of dissipating heat generated by an LED-based lighting system includes configuring a PCB with conductors on a front-side of the PCB, such that when one or more LEDs mounted to the conductors generates heat, the heat dissipates from the one or more LEDs to the conductors. The method also includes integrating a structural element such that at least portions of the conductors face the structural element, and the heat dissipates from the conductors to the structural element.

Claims

1. An LED (light-emitting diode)-based lighting system, comprising:

a PCB (printed circuit board) having conductors on a front-side thereof, the conductors occupying at least 50% of a front-side area of the PCB;

one or more LEDs mounted with the conductors; and

a structural element comprising a metal rail that forms a corresponding aperture in one to one relationship with each of the one or more LEDs, such that each of the one or more LEDs is centered within its corresponding aperture;

the PCB being mounted with the conductors proximate to the structural element so that heat generated by the one or more LEDs primarily dissipates through the conductors and the structural element.

2. The lighting system of claim 1, wherein the PCB comprises an epoxy glass substrate.

3. The lighting system of claim 1, further comprising a dielectric film between the PCB and the structural element.

4. The lighting system of claim 1, wherein the conductors occupy at least 70% of the front-side area of the PCB.

5. The lighting system of claim 1, wherein any components mounted on the front-side of the PCB consist of the one or more LEDs.

6. The lighting system of claim 1, the conductors being first conductors, and further comprising one or more metal-filled vias from the first conductors to second conductors on a back-side of the PCB.

7. The lighting system of claim 6, further comprising one or more heat sinks in thermal communication with the second conductors.

8. The lighting system of claim 7, the one or more heat sinks comprising one or more of passive structures and active devices.

9. A method of dissipating heat generated by an LED (light-emitting diode)-based lighting system, comprising:

configuring a PCB (printed circuit board) with one or more conductors on a front-side thereof, with the conductors occupying at least 50% of a front-side area of the PCB, such that when one or more LEDs mounted to the conductors generates heat, the heat dissipates from the one or more LEDs to the conductors, and

integrating the PCB to a structural element comprising a metal rail that forms a corresponding aperture in one to one relationship with each of the one or more LEDs, such that each of the one or more LEDs is centered within its corresponding aperture, such that at least portions of the one or more conductors face the structural element, and a majority of the heat dissipates from the conductors to the structural element.

10. Method of claim 9, wherein the step of configuring includes specifying the conductors to have a thickness greater than required to supply current to the one or more LEDs.

11. Method of claim 9, wherein the step of configuring includes specifying the PCB to include an epoxy glass substrate.

12. Method of claim 9, wherein the steps of configuring and integrating include maximizing area of the conductors that face the structural element.

13. Method of claim 9, wherein the steps of configuring and integrating include configuring the PCB such that the LEDs mount on the front-side and any other components mount on a back-side of the PCB.