Light emitting diode bulb having high heat dissipating efficiency

• US 6,864,513 B2
• Filed: 05/07/2003
• Issued: 03/08/2005
• Est. Priority Date: 05/07/2003
• Status: Expired due to Fees

• Current Assignee: Kaylu Industrial Corporation
• Original Assignee: Kaylu Industrial Corporation
• Inventors: Lin, Ting-Hao, Kuo, Li-Wei
• Primary Examiner(s): Flynn, Nathan J.
• Assistant Examiner(s): ANDUJAR, LEONARDO
• Application Number:
  US10/431,013
• Publication Number:
  US 20040222516A1
• Time in Patent Office: 671 Days
• Field of Search: 257/257, 257 81- 93, 257/712, 257/723, 257290-293, 257/675
• US Class Current: 257/99
• 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 9/232 specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb
• CPC Class Codes: F21K 9/233 specially adapted for generating a spot light distribution, e.g. for substitution of reflector lamps
• CPC Class Codes: F21V 29/67 characterised by the arrangement of fans
• CPC Class Codes: F21V 29/677 the fans being used for discharging
• CPC Class Codes: F21V 29/74 with fins or blades
• 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 29/89 Metals
• CPC Class Codes: F21W 2111/00 Use or application of lighting devices or systems for signalling, marking or indicating, not provided for in codes F21W2102/00 – F21W2107/00
• CPC Class Codes: F21W 2121/00 Use or application of lighting devices or systems for decorative purposes, not provided for in codes F21W2102/00 – F21W2107/00
• CPC Class Codes: F21Y 2113/17 forming a single encapsulated light source
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

A light emitting diode (LED) bulb includes a heat sink, a circuit layer having two opposite sides, multiple LEDs mounted on one side and an electrical insulating layer connected between the opposite side and the heat sink. Heat generated by the LEDs is conducted to the heat sink through the circuit layer and the electrical insulting layer and is dissipated quickly. Further, a fan can be mounted on the fins to dissipate heat from the heat sink more quickly. Therefore, the LED bulb has good heat dissipating efficiency.

Claims

1. A light emitting diode (LED) bulb comprising:

a seat having a driving circuit, a bottom and sides;

a threaded plug connected to the bottom of the seat and adapted to connect to a bulb socket;

an external protector having sides and a top edge, wherein the sides of the external protector are mounted around the sides of the seat; and

an LED module mounted on the seat and connected to the driving circuit wherein the LED module comprises;

a heat sink having multiple fins and a base with a top and a bottom;

an electrical insulting layer formed on the top of the heat sink;

a circuit layer made of a highly electrical conductive material and formed on the electrical insulting layer, wherein the circuit layer has a front side and a rear side and is composed of multiple pad sets and the driving circuit is electrically connected to the pad sets, wherein each pad set has a die pad and at least one bonding pad corresponding to the die pad; and

multiple LEDs mounted on the front side of the circuit layer, wherein each of the multiple LEDs has a chip connected to one of the die pads, at least one wire bonded between the chip and the at least one bonding pad corresponding to the die pad on which the chip is mounted and an encapsulant covering the chip and the at least one wire bonded between the chip and the bonding pad corresponding to the die pad;

whereby heat from the LEDs is immediately conducted to the heat sink through the circuit layer and electrical insulting layer to dissipate from the LED module.

2. The LED bulb as claimed in claim 1, wherein the electrical insulting layer is an oxidation layer.

3. The LED bulb as claimed in claim 1, wherein the electrical insulting layer is a heat dissipating glue.

4. The LED bulb as claimed in claim 1, wherein each chip is a single color type.

5. The LED bulb as claimed in claim 1, wherein each chip is a multi-color type.

6. The LED bulb as claimed in claim 1 further comprising a fan mounted on the fins of the heat sink.

7. The LED bulb as claimed in claim 1, wherein the top edge of the external protector is higher than the LED module on the seat.

8. The LED bulb as claimed in claim 7 further comprising a fan mounted on the fins of the heat sink and held in the external protector.