Patent Application
20150226418
This application claims priority of Chinese Patent Application No. 201410046367.7, filed on Feb. 10, 2014, the entire disclosure of which is hereby incorporated by reference.
1. Field of the Invention
This invention relates to a light emitting device, more particularly to a LED light emitting device.
2. Description of the Related Art
Referring to
Therefore, the object of the present invention is to provide a LED light emitting device that can overcome the aforesaid drawback of the prior art.
According to this invention, a LED light emitting device includes a heat dissipating substrate, a heat reflective layer disposed on the heat dissipating substrate, a circuit unit disposed on the heat dissipating substrate and spaced apart from the heat reflective layer, and a LED chip unit insulatively disposed on the heat reflective layer and electrically connected to the circuit unit.
Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiment of this invention, with reference to the accompanying drawings, in which:
Referring to
The heat dissipating substrate 2 is used for dissipating the heat generated by the LED chip unit 501, and is preferably made of metal, e.g., aluminum. In this embodiment, the heat dissipating substrate 2 is configured as a disk, and has a central portion 21 and a surrounding portion 22 extending upwardly from a periphery of the central portion 21 so as to define an indentation 23 in the heat dissipating substrate 2. In this embodiment, the indentation 23 is configured as a rectangle. However, it should be noted that the shapes of the heat dissipating substrate 2 and the indentation 23 are not limited and may vary based on actual requirements.
The heat reflective layer 3 is made of metal, is located in the indentation 23 of the heat dissipating substrate 2, and has a reflective surface 31 that is smooth and that is capable of reflecting light and heat generated by the LED chip unit 501 away from the heat dissipating substrate 2 toward an exterior environment through radiation. The heat reflective layer 3 may be deposited on the heat dissipating substrate 2 using vacuum deposition. Examples of the metal for the heat reflective layer 3 include nickel and silver.
The circuit unit 4 is disposed on the surrounding portion 22 of the heat dissipating substrate 2. In this embodiment, the circuit unit 4 includes a lower copper layer 41 disposed on a top surface of the surrounding portion 22 of the heat dissipating substrate 2, an insulating layer 43 disposed on the lower copper layer 41 oppositely of the heat dissipating substrate 2, and an upper copper layer 42 disposed on the insulating layer 43 oppositely of the lower copper layer 41. Since the structure of the circuit unit 4 of the LED light emitting device is well known to a skilled artisan, a detailed description thereof is omitted herein for the sake of brevity.
The LED chip unit 501 includes a plurality of LED chips 51 that are spaced apart from each other.
The LED light emitting device further includes an insulating adhesive unit 502 for adhesion of the LED chip unit 501 to the heat reflective layer 3, and a conductive wire unit 503 electrically connecting the LED chip unit 501 to the circuit unit 4. The insulating adhesive unit 502 includes a plurality of insulating adhesives 52 that are respectively disposed between the LED chips 51 and the heat reflective layer 3. The conductive wire unit 503 includes a plurality of conductive wires 53 to interconnect the LED chips 51 and connect some of the LED chips 51 to the upper copper layer 42 so as to achieve electrical connection between the LED chip unit 501 and the circuit unit 4. It should be noted that the numbers of the LED chips 51, the insulating adhesives 52 and the conductive wires 53 are not limited and may vary to meet actual requirements.
The LED light emitting device further includes a fluorescent layer 54 encapsulating the LED chip unit 501. The fluorescent layer 54 is light-transmissible and is capable of filtering light and/or improving uniform luminance.
The LED light emitting device further includes an electronic mechanism 6 that is disposed on and electrically connected to the circuit unit 4. The electronic mechanism 6 includes a processor 62 for current control and a rectifier 61 for converting alternating current to direct current.
In use, when the light emitting device is turned on, heat generated by the LED chips 51 is partly reflected by the heat reflective layer 3 via heat radiation and is partly conducted by the heat reflective layer 3 to the heat dissipating substrate 2 via heat conduction. Since the insulating layer 43 of the circuit unit 4 is spaced apart from the LED chips 51, the insulating layer 43 will not adversely affect the heat dissipation between the LED chips 51 and the heat dissipating substrate 2 so that the undesired heat can be effectively dissipated.
In addition, part of the light illuminated from the LED chips 51 and traveling to the heat reflective layer 3 could be reflected by the heat reflective layer 3 toward a direction away from the indentation 23 so that the illuminating efficiency of the LED light emitting device could be improved. Moreover, with the arrangement of the LED chip unit 501 in the indentation 23 of the heat dissipating substrate 2, the rectifier 61 and the processor 62 disposed on the surrounding portion 22 of the heat dissipating substrate 2 would not be adversely affected by the heat generated by the LED chip unit 501 so that the rectifier 61 and the processor 62 are able to be disposed at a position adjacent to the LED chips 51. As such, the size of the LED light emitting device according to this invention can be minimized.
While the present invention has been described in connection with what is considered the most practical and preferred embodiment, it is understood that this invention is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation and equivalent arrangements.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201410046367.7 | Feb 2014 | CN | national |
