LED lighting systems for product display cases

• US 7,954,979 B2
• Filed: 05/25/2005
• Issued: 06/07/2011
• Est. Priority Date: 05/26/2004
• Status: Active Grant

• Current Assignee: Current Lighting Solutions, LLC (f/k/a GE Lighting Solutions, LLC) (American Industrial Partners)
• Original Assignee: GE Lighting Solutions LLC (Savant Systems, LLC)
• Inventors: Bohler, Chris, Petroski, James, Wesorick, Melissa, Sommers, Mathew, Mayer, Mark
• Primary Examiner(s): Sawhney; Hargobind S
• Application Number:
  US11/137,598
• Publication Number:
  US 20050265019A1
• Time in Patent Office: 2,204 Days
• Field of Search: 362/127, 362/133, 362/134, 362/800, 362/545, 362/92, 362/125, 362/217.01, 362/217.02, 362/217.04, 362/217.05, 362/217.08, 362/21, 362/7.09, 362/217.1, 362/217.11, 362/217.12, 362/217.13, 362/217.14, 362/217.15, 362218-225, 362/235, 362240-248, 362/249.01, 362/249.02, 362/255, 362/297, 362326-328, 362/341, 362/373, 362/455
• US Class Current: 362/217.01
• CPC Class Codes: A47F 3/001 Devices for lighting, humidifying, heating, ventilation
• CPC Class Codes: A47F 3/0426 Details
• CPC Class Codes: F21S 4/20 with light sources held by or within elongate supports
• CPC Class Codes: F21V 15/015 Devices for covering joints between adjacent lighting devices; End coverings
• CPC Class Codes: F21V 19/001 the light sources being semiconductors devices, e.g. LEDs
• CPC Class Codes: F21V 29/717 using split or remote units thermally interconnected, e.g. by thermally conductive bars or heat pipes
• CPC Class Codes: F21V 29/767 the planes containing the fins or blades having directions perpendicular to the light emitting axis
• CPC Class Codes: F21V 29/77 with essentially identical diverging planar fins or blades, e.g. with fan-like or star-like cross-section
• CPC Class Codes: F21W 2131/305 for refrigerators
• CPC Class Codes: F21W 2131/405 for shop-windows or displays
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: F25D 27/00 Lighting arrangements in general F21

Abstract

A lighting assembly for illuminating a display case includes an LED that illuminates items placed in the display case. The lighting assembly can attach to a door, a door frame, or another structure of the display case.

Claims

1. A lighting assembly for illuminating a display case, the assembly comprising:

an elongated heat sink that is symmetrical along a longitudinal axis and is in thermal communication with a plurality of LEDs, wherein the longitudinal axis comprises an optical axis of the LEDs, the elongated heat sink being dimensioned having a height z and a length y, which is the greatest dimension, each LED device being disposed below the height z such that each LED device is not visible when viewing the assembly from a side along the length y, wherein the elongated heat sink includes at least an upper fin, central fin, and lower fin that run parallel to and are disposed on opposite sides of the longitudinal axis, wherein the upper fins are angled downwardly toward the longitudinal axis and include an upper longitudinal edge that is disposed above the LED devices;

at least one reflector disposed in relation to the LED devices to reflect light emitted from the LED device, wherein the reflector is shaped to direct light in opposite directions away from the longitudinal axis of the assembly; and

a cover including a translucent middle portion and integral darkened side portions adapted to fit around the upper longitudinal edge of the upper fins of said heat sink, wherein the darkened side portions further obscure the LED devices from view and do not transmit light.

2. The assembly of claim 1, further comprising power conditioning circuitry for converting AC power to DC power and for correcting polarity of the power.

3. The assembly of claim 1, further comprising a stand off connected to the heat sink for spacing the heat sink from a surface of the display case.

4. The assembly of claim 1, further comprising a mounting structure connected to the heat sink, wherein the mounting structure is configured to be received by a clip used to mount a fluorescent fixture inside a refrigerated display.

5. The assembly of claim 1, further comprising a thermally conductive substrate upon which each LED device is mounted, the LED devices being in thermal communication with the heat sink via the thermally conductive substrate.

6. The assembly of claim 5, further comprising a thermally conductive layer interposed between the substrate and the heat sink, the thermally conductive layer filling voids that occur when the substrate is brought adjacent the heat sink.

7. The assembly of claim 1, wherein the reflector is shaped and disposed in relation to each LED device such that the reflector allows light from the LED devices to pass over the reflector to illuminate products disposed in the display case.

8. The assembly of claim 1, further comprising an end cap attached to the heat sink, wherein the end cap and the heat sink each include fastener openings to receive a fastener for attaching the end cap to the heat sink.

9. The assembly of claim 1, wherein the reflector includes LED openings extending through the reflector and aligned with the longitudinal axis, each LED opening receiving a respective LED device.

10. A light assembly for illuminating products in a refrigerated display case on opposite sides of a mullion, the assembly comprising:

a thermally conductive printed circuit board wherein a plurality LED devices are mounted to an upper surface of the circuit board;

a heat sink having a plurality of fins, including at least a pair of upper fins disposed on opposite sides of the longitudinal axis, that run parallel to and are angled downwardly toward the longitudinal axis, in thermal communication with the LEDs, wherein the longitudinal axis comprises an optical axis of the LEDs, wherein heat from the LEDs is drawn through the circuit board and dissipated through a lower surface of the circuit board into the heat sink;

an end cap connected to a longitudinal end of the heat sink;

a reflector disposed in relation to the LEDs such that light is directed into the display case and away from the longitudinal axis toward opposite sides of the mullion, said reflector including at least one ridge that run parallel to said longitudinal axis; and

a cover disposed over the LEDs and connected to both the heat sink and the end cap, the cover including a translucent middle portion and integral darkened side portions adapted to fit around an upper longitudinal edge of the upper fins of said heat sink.

11. The light assembly of claim 10, wherein the heat sink has a width about equal to a width of the mullion.

12. The assembly of claim 10, wherein the upper fins include a mounting surface for the reflector.

13. The assembly of claim 12, wherein the upper fin of the heat sink vertically taller than the LEDs and the LEDs are positioned below the height z.

14. A light assembly for illuminating a display case comprising:

an elongated heat sink having a channel and angled heat fins, including at least a pair of upper fins disposed on opposite sides of said channel, running along a greatest dimension of the heat sink;

wherein the longitudinal axis comprises an optical axis of each LED,

a printed circuit board (“

PCB”

) received in the channel of the heat sink;

a plurality of LED devices mounted along a longitudinal axis of the PCB and in thermal communication with the heat sink, the LED devices being disposed below an uppermost edge of the upper fins so that the LED devices are not visible when viewing the assembly from a side along the greatest dimension of the heat sink;

a reflector connected to the heat sink for directing light from at least one of the LED devices in a direction away from the longitudinal axis of the assembly, said reflector including at least one ridge that runs parallel to said longitudinal axis; and

a cover including a translucent top portion and integral darkened side portions adapted to fit around the upper longitudinal edge of the upper fins of said heat sink wherein the darkened side portions further obscuring the LED devices from view and do not transmit light.

15. The assembly of claim 14, wherein a lower surface of the reflector contacts the upper fin of the heat sink.

16. A lighting assembly for illuminating a display case, the assembly comprising:

a circuit board having a longitudinal dimension substantially longer than a width of the circuit board;

a plurality of LED devices disposed on the circuit board along the longitudinal extent of the circuit board, said LED devices in thermal communication with the circuit board;

an elongated heat sink in thermal communication with the circuit board, the longitudinal extent of the heat sink corresponding to the longitudinal extent of the circuit board, the heat sink comprising;

a circuit board mounting surface along the longitudinal extent of the heat sink; and

a downwardly angled fin extending along the longitudinal extent of the heat sink on opposite sides of the circuit board mounting surface;

a reflector in light reflecting relationship with the LED devices to reflect side-emitted light from the LED devices in a direction away from the longitudinal extent of the assembly such that most of the emitted light is reflected to either side of the assembly in a direction that is not perpendicular to the circuit board mounting surface, said reflector including at least one ridge that run parallel to said longitudinal extent of the assembly; and

a cover including a translucent middle portion and integral darkened side portions adapted to fit around the upper longitudinal edge of the downwardly angled fin of said heat sink, the cover attaching to the heat sink and wherein the darkened side portions further obscuring the LED devices from view and do not transmit light.

17. The assembly of claim 16, wherein an upper edge of each fin extends away from and above an upper surface of the LED devices.