Patent Application
20130250584
1. Field of the Invention
The invention relates in general to light emitting device, and more particularly to a light emitting device with excellent heat dissipation efficacy.
2. Description of the Related Art
Currently, light emitting device, such as a light emitting diode (LED) lamp, has replaced the traditional fluorescent bulb lamp for some advantages such as higher lifespan, lower power consumption and smaller size. A LED lamp requires a light housing for fixing and protecting the LEDs. The heat dissipating efficacy of the light housing is important since the LEDs can be damaged by the thermal generating from the LEDs. Typically, a heat spreader is disposed on the heat dissipating side of the light housing for promoting the heat dissipating efficacy of the light housing.
In one type of the conventional LED lamp on street, heat spreader is exposed to the outside. This exposed heat spreader increases the surface area of the heat dissipating surface on the housing of the LED lamp, and remains the light emitting surface of the LED lamp at relatively low temperature when the high power LEDs on the light emitting surface of the LED lamp are working. However, the dust and sand are easily deposited on the gap of the exposed heat spreader.
However, heat dissipating efficacy of the light housing is unsatisfactory for the market requirements, since a large amount of the heat-insulating air surrounding the heat spreader are also enclosed in the light housing.
Therefore, the present invention relates to a light emitting device with excellent heat dissipation efficacy.
The present invention provides a light emitting device comprising: a housing comprising a first part and a second part connecting the first part, wherein the first part comprises a first side, a second side and a middle portion connecting the first side and the second side, and a thickness of the first side and a thickness of the second side are thinner than that of the middle portion; and a LED module disposed on the housing for emitting light.
The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:
The LED module 130 is disposed within the housing 110. The LED module 130 comprises a plurality of LEDs (not illustrated) and a substrate (not illustrated), wherein the LEDs are disposed on the substrate.
The housing 110 comprises a first part 111 and a second part 112 connected to the first part 111. The first part 111 and the second part 112 may be integrated into one piece by using way of die casting, for example. In addition, the housing 110 is made from thermal conductive metal material, such as aluminum, copper or a combination thereof.
The LED emitting device 100 further comprises a daylight sensor 120, which is disposed on the second part 112 of the housing 110 for detecting the daylight. A power saving mode (not illustrated) is switched on when daylight is detected by the daylight sensor 120, and the LEDs in the LED module 130 are driven to emit light.
The LED emitting device 100 further comprises a bottom cover (not illustrated), wherein the bottom cover covers the first recess 110r1 and the second recess 110r2 to protect the LED module 130 from the invasion of dust and sand.
The middle portion 1113 has at least one hole 1113h. The LED module 130 is fixed in the first part 111 through at least one screw (if the hole 1113h is screw hole) or at least one fasten element fixing (not illustrated) in the hole 1113h. In addition, the hole 1113h is blind hole or through hole, for example.
In
In addition, the thickness of the first side 1111 is substantial equal to that of the second side 1112. In present embodiment, the first side 1111 and the second side 1112 are formed as a symmetrical structure. In another embodiment, the thickness of the first side 1111 is different from that of the second side 1112.
The first side 1111 is extended downward and getting thinner from an edge of the middle portion 1113. The second side 1112 is extended downward and getting thinner from another edge of the middle portion 1113.
The thickness of the third side 1114 and the thickness of the fourth side 1115 are thinner than that of the middle portion 1113, so that most of the heat generated from the LED module 130 can quickly be conducted to the third side 1114 and the fourth side 1115 from the middle portion 1113, and then most of the heat is convected away from the third side 1114 and the fourth side 1115. Under the circumstances, an extra heat spreader may not be required by the LED emitting device 100, but such embodiment is not meant to be limiting. In one embodiment, the thickness of the middle portion 1113 ranges between 1.0 and 8.0 times as much as that of the third side 1114 and/or the fourth side 1115.
In addition, the thickness of the third side 1114 is substantial equal to that of the fourth side 1115. In another embodiment, the thickness of the third side 1114 is different from that of the fourth side 1115.
The third side 1114 and the fourth side 1115 are formed as an asymmetrical structure. For example, the third side 1114 is extended downward and getting thinner from an edge of the middle portion 1113, and the fourth side 1115 is extended upward and getting thinner from another edge of the middle portion 1113. In another embodiment, the third side 1114 and the fourth side 1115 are formed as a symmetrical structure. For example, the third side 1114 is extended downward and getting thinner from an edge of the middle portion 1113, and the fourth side 1115 is extended downward and getting thinner from another edge of the middle portion 1113.
In
While the invention has been described by way of example and in terms of the preferred embodiment(s), it is to be understood that the invention is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures.
This application claims the benefit of U.S. provisional application Ser. No. 61/614,019, filed Mar. 22, 2012, the subject matter of which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 61614019 | Mar 2012 | US |
