HEAT DISSIPATION ENHANCED LED LAMP FOR SPOTLIGHT

• US 20100320892A1
• Filed: 02/17/2010
• Published: 12/23/2010
• Est. Priority Date: 06/19/2009
• Status: Abandoned Application

• Current Assignee: Chih-Ming Yu
• Original Assignee: Chih-Ming Yu
• Inventors: YU, Chih-Ming
• Application Number:
  US12/706,935
• Publication Number:
  US 20100320892A1
• Time in Patent Office: Days
• US Class Current: 313/46
• CPC Class Codes: F21K 9/23 Retrofit light sources for lighting devices with a single fitting for each light source, e.g. for substitution of incandescent lamps with bayonet or threaded fittings
• CPC Class Codes: F21K 9/238 Arrangement or mounting of circuit elements integrated in the light source
• CPC Class Codes: F21V 23/006 the substrate being distinct from the light source holder
• CPC Class Codes: F21V 29/71 using a combination of separate elements interconnected by heat-conducting means, e.g. with heat pipes or thermally conductive bars between separate heat-sink elements
• CPC Class Codes: F21V 7/048 with facets structure
• CPC Class Codes: F21V 7/24 characterised by the material
• CPC Class Codes: F21V 7/28 characterised by coatings
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

In a LED lamp, a thermally conductive electric insulator is filled in a cavity of a lamp base, a LED filament includes an AC LED device, a resistor is connected with the AC LED device in series between two electrodes of the lamp base to form an electric loop, and a reflective cup has a hole at a bottom thereof to expose the AC LED device and a reflective surface to reflect light of the AC LED device for providing a spotlight. The thermally conductive electric insulator mechanically contacts the LED filament and the first one of the two electrodes, and thereby establishes a heat dissipation channel from the AC LED device to the first electrode therethrough.

Claims

1. A LED lamp comprising:

a LED filament including an AC LED device of a rated power ranging from 0.3 to 5 W;

a lamp base having two electrodes and a cavity, the first electrode having a spiral-threaded, columnar, or needle-like configuration;

a resistor of a resistance ranging from 50 to 50,000Ω

, electrically connected with the AC LED device in series between the two electrodes to form an electric loop;

a thermally conductive electric insulator of a thermal conductivity ranging from 0.25 to 30 W/mK, filled in the cavity and mechanically contacting with the filament and the first electrode to thereby establish a heat dissipation channel from the AC LED device to the first electrode through the thermally conductive electric insulator; and

a reflective cup having a hole at a bottom thereof to expose the AC LED device and a reflective surface at an inner surface thereof to reflect light of the AC LED device, for producing a spotlight.

2. The LED lamp of claim 1, wherein the reflective cup is fixed on the lamp base or the thermally conductive electric insulator.

3. The LED lamp of claim 1, wherein the LED filament comprises a circuit board soldered to the first electrode and having the AC LED device bounded thereon.

4. The LED lamp of claim 3, wherein the reflective cup is fixed on the circuit board.

5. The LED lamp of claim 4, wherein the reflective cup is detachable from the circuit board.

6. The LED lamp of claim 4, wherein the reflective cup has one or more pins inserted in the circuit board.

7. The LED lamp of claim 4, wherein the reflective cup is glued to or clamped on the circuit board.

8. The LED lamp of claim 1, wherein the reflective cup comprises:

a plastic cup; and

a highly reflective film coated on a portion of the inner surface of the plastic cup.

9. The LED lamp of claim 1, wherein the reflective cup comprises a metal cup having the reflective surface.

10. The LED lamp of claim 1, wherein the AC LED device comprises an AC LED epitaxial chip packaged with the resistor in a same package.

11. The LED lamp of claim 1, wherein the thermally conductive electric insulator comprises an epoxy resin, thermal conductor powder, or a mixture thereof.

12. The LED lamp of claim 1, wherein the lamp base is one of the standard E12, E14, E17, E26, E27, MR16, and GU10 lamp bases.

13. The LED lamp of claim 1, wherein the rated power of the AC LED device ranges from 1 to 3 W.

14. The LED lamp of claim 3, wherein the LED filament comprises a thermally conductive member passing through the circuit board, and having a first end bounded with the AC LED device thereon and a second end buried in the thermally conductive electric insulator.

15. The LED lamp of claim 3, wherein the thermally conductive electric insulator directly contacts the circuit board.

16. The LED lamp of claim 1, wherein the LED filament comprises a thermally conductive member having a dish at a first end bounded with the AC LED device thereon and a second end buried in the thermally conductive electric insulator.

17. The LED lamp of claim 1, wherein the thermally conductive electric insulator directly contacts the AC LED.