Thermally efficient LED bulb

• US 20050254264A1
• Filed: 05/12/2004
• Published: 11/17/2005
• Est. Priority Date: 05/12/2004
• Status: Active Grant

• Current Assignee: OSRAM GmbH (Ams-Osram AG)
• Original Assignee: OSRAM Sylvania Inc. (Ams-Osram AG)
• Inventors: Sidwell, Steven C., Coushaine, Charles M., Lyman, Paul
• Granted Patent: US 7,086,767 B2
• Time in Patent Office: Days
• US Class Current: 362/655
• CPC Class Codes: F21K 9/232 specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb
• CPC Class Codes: F21S 43/14 Light emitting diodes [LED]
• CPC Class Codes: F21S 43/195 Details of lamp holders, terminals or connectors
• CPC Class Codes: F21S 45/47 Passive cooling, e.g. using fins, thermal conductive elements or openings
• CPC Class Codes: F21V 29/58 characterised by the coolants
• 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 29/767 the planes containing the fins or blades having directions perpendicular to the light emitting axis
• CPC Class Codes: F21V 3/00 Globes; Bowls; Cover glasses with refracting properties F21V5/00; with reflecting properties F21V7/00; characterised by cooling arrangements F21V29/506
• CPC Class Codes: F21W 2103/00 Exterior vehicle lighting devices for signalling purposes
• CPC Class Codes: F21Y 2107/30 on the outer surface of cylindrical surfaces, e.g. rod-shaped supports having a circular or a polygonal cross section
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

A solid-state light source 10 compatible with existing sockets normally reserved for filamented lamps may be formed with a hollow base 12 formed to mechanically and electrically adapt to a socket. A sub-assembly 14 adapted to cooperate with and fit into the hollow base 12 comprises a metal core 16 having a bulbous body 18 and a narrow, depending foot 20. A circuit board 22 substantially surrounds the metal core 16 on two sides. The board 22 is preferably formed from a flexible printed circuit board material capable of sustaining a bend radius of at least 0.25 inches (6 mm). Solid-state light sources 30, for example, light emitting diodes (LEDs) are mechanically and electrically connected to one side of the circuit board by suitable electrically conductive traces. A glass dome 34 covers the sub-assembly 14 after it is inserted into the hollow base 12 and is sealed thereto.

Claims

1. A solid-state light source compatible with existing sockets normally reserved for filamented lamps comprising:

a hollow base formed to mechanically and electrically adapt to a socket; and

a sub-assembly adapted to cooperate with and fit into said hollow base, said sub-assembly comprising;

a metal core having a bulbous body and a narrow foot depending therefrom;

a circuit board substantially surrounding said metal core on two sides, said circuit board having a bulbous body positioned about said bulbous body of said metal core and having two spaced apart legs lying adjacent either side of said narrow foot;

a plurality of solid-state light sources mechanically and electrically connected to one side of said circuit board;

external electrical contacts positioned on said circuit board for connection to an electrical circuit; and

a glass dome covering said bulbous body of said circuit board and sealed to said hollow base.

2. The solid-state light source of claim 1 wherein a thermally efficient fluid fills the interior of said dome.

3. The solid-state light source of claim 1 wherein said sides of said metal core not covered by said circuit board are provided with heat radiating ribs.

4. The solid-state light source of claim 1 wherein said hollow base includes a locking receptacle and said metal core includes a matching lock.

5. The solid-state light source of claim 1 wherein at least one of said legs of said circuit board is provided with a latch and said hollow base has a latch receiver to mate therewith.

6. A method of making a heat remover to remove heat from a lamp comprised of multiple LEDs, the steps comprising:

preparing a flexible printed circuit board containing multiple LEDs operatively mounted thereon;

preparing a metal core;

forming said flexible printed circuit board about said metal core; and

fixing said flexible circuit board to said metal core.

7. The method of claim 6 wherein said flexible circuit board has circuit ends and said circuit ends are fixed in a hollow base for making electrical contact with an external circuit.