Thermally efficient LED bulb

• US 7,086,767 B2
• Filed: 05/12/2004
• Issued: 08/08/2006
• 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: Lyman, Paul, Sidwell, Steven C., Coushaine, Charles M.
• Primary Examiner(s): O'Shea, Sandra
• Assistant Examiner(s): Cranson, Jr., James W
• Application Number:
  US10/843,811
• Publication Number:
  US 20050254264A1
• Time in Patent Office: 818 Days
• Field of Search: 362/227, 362/240, 362/294, 362/545, 362/555, 362/249, 362/362, 315/185.R
• US Class Current: 362/545
• 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 flexible circuit board flexed to be formed about said metal core, and surround 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. 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;

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

wherein said sides of said metal core not covered by said circuit board are provided with heat radiating ribs.

3. 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;

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

wherein said hollow base includes a locking receptacle and said metal core includes a matching lock.

4. 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;

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

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.