LED lighting assemblies with thermal overmolding

• US 8,371,723 B2
• Filed: 11/23/2011
• Issued: 02/12/2013
• Est. Priority Date: 11/29/2005
• 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: Nall, Jeffrey, Mrakovich, Matthew
• Primary Examiner(s): HAN, JASON
• Application Number:
  US13/303,563
• Publication Number:
  US 20120063128A1
• Time in Patent Office: 447 Days
• Field of Search: 362/249.02, 362/311.02, 362/800
• US Class Current: 362/311.02
• CPC Class Codes: F21K 9/90 Methods of manufacture
• CPC Class Codes: F21S 4/10 with light sources attached to loose electric cables, e.g. Christmas tree lights
• CPC Class Codes: F21S 4/20 with light sources held by or within elongate supports
• CPC Class Codes: F21V 23/001 the elements being electrical wires or cables
• CPC Class Codes: F21V 23/005 the substrate is supporting also the light source
• CPC Class Codes: F21V 23/007 enclosed in a casing
• CPC Class Codes: F21V 23/023 Power supplies in a casing F21V23/003 takes precedence
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 29/85 characterised by the material liquid coolants F21V29/56
• CPC Class Codes: F21V 3/02 characterised by the shape
• CPC Class Codes: F21V 3/10 characterised by coatings
• CPC Class Codes: F21V 3/12 the coatings comprising photoluminescent substances
• CPC Class Codes: F21V 31/04 Provision of filling media
• CPC Class Codes: F21V 9/06 for filtering out ultraviolet radiation
• CPC Class Codes: F21Y 2101/00 Point-like light sources
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G09F 9/33 being semiconductor devices, e.g. diodes
• 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 1/181 associated with surface mounted components
• CPC Class Codes: H05K 2201/0129 : Thermoplastic polymer, e.g. auto-adhesive layer; Shaping of thermoplastic polymer
• CPC Class Codes: H05K 2201/0209 : Inorganic, non-metallic particles
• CPC Class Codes: H05K 2201/10106 : Light emitting diode [LED]
• CPC Class Codes: H05K 2203/1316 : Moulded encapsulation of mounted components
• CPC Class Codes: H05K 3/284 : for encapsulating mounted components H05K1/185 takes precedence
• CPC Class Codes: H05K 3/32 : electrically connecting electric components or wires to printed circuits
• CPC Class Codes: Y10T 29/4913 : Assembling to base an electrical component, e.g., capacitor, etc.
• CPC Class Codes: Y10T 29/49146 : with encapsulating, e.g., potting, etc.

Abstract

One or more light emitting diode diodes (LEDs) are attached to a printed circuit board. The attached LEDs are connectable with a power source via circuitry of the printed circuit board. An overmolding material is insert molded an over at least portions of the printed circuit board proximate to the LEDs to form a free standing high thermal conductivity material overmolding that covers at least portions of the printed circuit board proximate to the LEDs. The free standing high thermal conductivity material has a melting temperature greater than about 100° C. and has a thermal conductivity greater than or about 1 W/m·K. In some embodiments, the free standing high thermal conductivity material is a thermoplastic material.

Claims

1. A lighting assembly comprising:

a printed circuit board;

one or more light emitting diodes (LEDs) disposed on the printed circuit board and connectable with a power source via circuitry of the printed circuit board;

the LEDs comprised of a semiconductor chip and a lens;

a free standing thermoplastic overmolding encapsulating the printed circuit board, the thermoplastic of the freestanding thermoplastic overmolding having a melting temperature greater than about 100°

C. and having a thermal conductivity greater than or about 1 W/m·

K; and

a light transmissive cover disposed over one or more of the one or more LEDs, the thermoplastic overmolding encapsulating the printed circuit board and not covering at least a portion of the light-transmissive cover.

2. The lighting assembly as set forth in claim 1, wherein the thermoplastic of the thermoplastic overmolding has a thermal conductivity greater than or about 10 W/m·

K.

3. The lighting assembly as set forth in claim 1, wherein the free standing thermoplastic overmolding does not encapsulate the one or more LEDs disposed on the printed circuit board.

4. The lighting assembly as set forth in claim 1, wherein the free standing thermoplastic overmolding encapsulating the printed circuit board does not cover light-emitting apertures of the one or more LEDs.

5. The lighting assembly as set forth in claim 1, wherein the lighting assembly does not include a container or housing configured to contain the free standing thermoplastic overmolding.

6. A lighting assembly comprising:

a printed circuit board;

one or more light emitting diodes (LEDs) disposed on the printed circuit board and connectable with a power source via circuitry of the printed circuit board;

a phosphor disposed in a lens overlaying the one or more LEDs; and

an overmolded housing comprising thermoplastic overmolding material encapsulating the printed circuit board; and

a light transmissive cover disposed over the one or more LEDs, the thermoplastic overmolding encapsulating the printed circuit board and not covering at least a portion of the light-transmissive cover.

7. The lighting assembly as set forth in claim 6, wherein the phosphor coats the one or more LEDs.

8. The lighting assembly as set forth in claim 6, wherein the thermoplastic overmolding material does not encapsulate the one or more LEDs disposed on the printed circuit board.

9. The lighting assembly as set forth in claim 6, wherein the overmolded housing does not cover light-emitting apertures of the one or more LEDs.

10. The lighting assembly as set forth in claim 6, wherein the lighting assembly does not include a container or housing other than the overmolded housing.

11. The lighting assembly as set forth in claim 6, wherein the thermoplastic overmolding material has a melting temperature greater than about 100°

C.

12. A lighting assembly comprising:

a printed circuit board;

more than one light emitting diodes (LEDs) including lenses disposed on the printed circuit board and connectable with a power source via circuitry of the printed circuit board; and

a free standing thermoplastic overmolding encapsulating the printed circuit board;

wherein at least one LED comprises a group III-nitride-based electroluminescent semiconductor diodes; and

a light transmissive cover disposed over more than one LED, the thermoplastic overmolding encapsulating the printed circuit board are not covering at least a portion of the light transmissive cover.

13. The lighting assembly as set forth in claim 12, wherein the free standing thermoplastic overmolding does not encapsulate the one or more LEDs disposed on the printed circuit board.

14. The lighting assembly as set forth in claim 12, wherein the free standing thermoplastic overmolding encapsulating the printed circuit board does not cover light-emitting apertures of the one or more LEDs.

15. The lighting assembly as set forth in claim 12, wherein the lighting assembly does not include a container or housing configured to contain the free standing thermoplastic overmolding.

16. The lighting assembly as set forth in claim 12, wherein the light-transmissive cover includes a phosphor.

17. The lighting assembly as set forth in claim 12, further comprising:

a phosphor coating the one or more LEDs.

18. The lighting assembly as set forth in claim 17, wherein the phosphor comprises one of a white-light emitting phosphor blend and a yellowish-light emitting phosphor blend.

19. The lighting assembly as set forth in claim 12, wherein the thermoplastic of the freestanding thermoplastic overmolding has a melting temperature greater than about 100°

C.