| WO/2004/038286 | A DEPLOYABLE AIRFIELD LUMINAIRE |
| WO/2011/104102 | BASE CARRIER, LIGHT SOURCE CARRIER AND SYSTEM COMPRISING A BASE CARRIER AND A LIGHT SOURCE CARRIER |
| JP2004006253 | MULTICOLOR LED LIGHTING DEVICE |
LIU, Qing (Overseas Chinese Town, 5F Hantang Building OC, Shenzhen Guangdong 3, 51805, CN)
YANG, Canbang (Overseas Chinese Town, 5F Hantang Building OC, Shenzhen Guangdong 3, 51805, CN)
YE, Zesheng (Overseas Chinese Town, 5F Hantang Building OC, Shenzhen Guangdong 3, 51805, CN)
LI, Hao (Overseas Chinese Town, 5F Hantang Building OC, Shenzhen Guangdong 3, 51805, CN)
LIU, Qing (Overseas Chinese Town, 5F Hantang Building OC, Shenzhen Guangdong 3, 51805, CN)
YANG, Canbang (Overseas Chinese Town, 5F Hantang Building OC, Shenzhen Guangdong 3, 51805, CN)
YE, Zesheng (Overseas Chinese Town, 5F Hantang Building OC, Shenzhen Guangdong 3, 51805, CN)
| Claims 1. An exothermic electronic module (10), comprising an exothermic body (1 ), a board (2) and a heat sink (3), the exothermic body (1) is arranged on the board (2) , characterized in that, the board (2) is opened with a cavity (4), the heat sink (3) comprises a first portion (5) and a second portion (6) .said first portion (5) is mounted under the board (2) and said second portion is mounted in the cavity (4) . 2. The exothermic electronic module (10) according to Claim 1 , characterized in that a thermal conductive insulation layer (7) is disposed between the exothermic body (1) and the second portion (6). 3. The exothermic electronic module (10) according to Claim 2, characterized in that the thermal conductive insulation layer (7) is a silicon elastomer. 4. The exothermic electronic module (10) according to Claim 1 , characterized in that a thermal conductive layer is disposed between the exothermic body (1) and the second portion (6). 5. The exothermic electronic module (10) according to any one of Claim 1 -4, characterized in that the board (2) is an FR-4 board. 6. The exothermic electronic module (10) according to any one of Claim 1-4 characterized in that another thermal conductive layer (8) is further disposed between the board (2) and the first portion (5). 7. The exothermic electronic module (10) according to any one of Claim 1 -4, characterized in that the first portion (5) is integral with the second portion (6). 8. The exothermic electronic module (10) according to Claim 7, characterized in that the first portion (5) and the second portion (6) are made of aluminum material. 9. The exothermic electronic module (10) according to any one of Claim 1-4, characterized in that the first portion (5) and the second portion (6) are manufactured separately, with the second portion (6) being a heat pipe. 10. The exothermic electronic module (10) according to any one of Claim 1-4, characterized in that the contacting area of second portion (6) towards the exothermic body (1) is at least half the size of a base area of the exothermic body (1). 11. The exothermic electronic module (10) according to Claim 10, characterized in that the contacting area is approximately of the same size of the base area of the exothermic body (1). 12. A luminaire, comprising the exothermic electronic module as LED module according to any one of Claims 1-11. |
Exothermic electronic module
Technical Field
The present invention relates to exothermic electronic module, especially lighting module, more especially an LED module.
Background Art
LED is a widely used light source and also a light source with a relatively long lifetime. The LED in use requires an appropriate temperature condition. The performance of the LED will be affected If the temperature is beyond the appropriate temperature, and the advantage of long lifetime may be lost. Therefore, how to better transfer the heat generated by the LED chip, particularly after mounting the circuit board, becomes an important research hotspot. This problem is also the same problem faced by other exothermic electronic module.
In the current LED module or luminaire structure, the LED must be placed on the MCPCB (Metal Core Printed Circuit Board) in order to diffuse the heat generated by the LED. Refer to FIGS. 1a and 1b. FIGS. 1a and 1b are diagrams of an LED module 10 having the MCPCB board in the prior art and an enlarged view of the part indicated by the dashed lines in FIG. 1a, respectively. From FIGS. 1a and 1b, it can be seen that the LED module 0 comprises an optical cover 9 and at least one LED 1 disposed in the optical cover 9, a metallic board 2 for arranging the LED 1 and a heat sink 3. A solder paste 11, a copper layer 12 and a thermal conductive insulation layer 13 are disposed in succession between the LED 1 and the metallic board 2 (such as an aluminum board) under the LED 1. The heat sink 3 is disposed under the metallic board 2, and a thermal conductive layer 8 is further disposed between the board 2 and the heat sink 3. In an LED luminaire, the cost of the MCPCB board is up to 10% of the total cost of the luminaire.
Compared with the MCPCB board, the costs of other boards with poor heat dissipation properties, such as FR- circuit board, are quite low. Take the FR- board as an example, its cost is only 1/3 of that of MCPCB board. Therefore, if such other boards with poor heat dissipation properties, such as FR- board (the thermal conductivity of which is 0.3-0.5W/m*K), also can be used for the luminaire, then the cost of the luminaire will be reduced by 6%. But these other boards with poor heat dissipation properties, such as FR-4 board, give the limitation to the thermal management of the LED luminaire. Refer to FIGS. 2a and 2b. FIGS. 2a and 2b are diagrams of an LED module 10 having an FR-4 board in the prior art and an enlarged view of the part indicated by the dashed lines in FIG. 2a, respectively. From FIGS. 2a and 2b, it can be seen that the LED module 10 comprises an optical cover 9 and at least one LED 1 disposed in the optical cover 9, the FR-4 board 2 and a heat sink 3. A solder paste 11 and a copper layer 12 are disposed in succession between the LED 1 and the FR-4 board 2 under the LED 1. The heat sink 3 is disposed under the FR-4 board 2, and a thermal conductive layer 8 is further disposed between the FR-4 board 2 and the heat sink 3. This solution can only be used for a bw power LED.
In the prior art, a technical solution is provided by punching a copper core into the FR-4 board. But the manufacture costs in this solution will be still high, and the manufacture quality is also difficult to be controlled.
Therefore, it is urgent to solve the above one or more existing shortcomings in the exothermic electronic module, especially lighting module, more especially an LED module.
Summary of the Invention
The technical problem to be solved by the present invention is to provide an exothermic electronic module with low cost simple structure but good heat dissipation property. In order to solve this problem, the present invention provides an exothermic electronic module, comprising an exothermic body, a board and a heat sink, the exothermic body is arranged on the board, characterized in that, the board is opened with a cavity , the heat sink comprises a first portion and a second portion .said first portion is mounted under the board and said second portion is mounted in the cavity. A heat flow channel which is short as much as possible is provided between the exothermic body and the heat sink by opening a cavity in the board and by disposing the second portion of the heat sink in the cavity. While at the same time, by only providing the cavity of the board, the design of the board will also be much easier, simpler and be low-cost. Under the design of the board, by designing the heat sink with a first portion mounted under the board and a second portion mounted in the cavity, the good heat dissipation properties can be achieved. The whole cost of the exothermic electronic module will lower and the whole structure will be easier.
In order to further reduce the thermal resistance between the exothermic electronic module and the heat sink, the solder paste used in the FR-4 board of the prior art is not disposed between the exothermic body and the second portion of the heat sink, instead, a thermal conductive insulation layer Is disposed therebetween. By means of the above technical measures, good heat dissipation performance of the exothermic electronic module especially LED module with low cost is achieved. Alternatively, it is possible that a thermal conductive layer is disposed between the LED and the second portion of the heat sink for different exothermic electronic module.
According to one exemplary embodiment of the present invention, the thermal conductive insulation layer is a silicon elastomer. Then, not only insulation but also good thermal conductivity can be accomplished. The thermal conductive insulation layer also can be other materials with insulating function and good thermal conductivity.
Preferably, the above board can be an FR-4 board. Of course, it also can be other circuit boards with relative poor thermal conductivity.
Preferably, another thermal conductive layer is further provided between the board and the first portion so as to improve the thermal conductivity ability of the board to the first portion of the heat sink.
According to one exemplary embodiment of the present invention, the first portion is integral with the second portion. For example, both of them are made of aluminum with good heat dissipation properties and low costs. According to another alternative exemplary embodiment of the present invention, the first portion and the second portion are manufactured separately, with the second portion being a heat pipe. The heat pipe can be punched into or soldered onto the first portion.
According to one exemplary embodiment of the present invention, the contacting area of second portion towards the exothermic body is at least half the size of a base area of the exothermic body, preferably is approximately of the same size of the base area of the exothermic body so that the thermal conductivity can be further improved.
The present invention further relates to a luminaire comprising exothermic electronic module as LEO module having the above features.
Through the structure design of exothermic electronic module, especially the LED module, the circuit board with low cost, such as the FR-4 circuit board, can be used for a high power electronic device such as LED, which overcomes the defect of poor thermal conductivity of these circuit boards, such that an LED module with low cost, simple structure but good heat dissipation property is manufactured.
Brief Description of the Drawings
The present invention is further explained by combining with the drawings and the embodiments:
FIGS. 1a and 1b are diagrams of the LED module 10 having the CPCB in the prior art and an enlarged view of the part indicated by the dashed lines in FIG. 1a, respectively;
FIGS. 2a and 2b are diagrams of the LED module 10 having the FR-4 board in the prior art and an enlarged view of the part indicated by the dashed lines in FIG. 2a, respectively,
FIGS. 3a and 3b are diagrams of the exothermic electronic module as LED module according to the first embodiment of the present invention and an enlarged view of the part indicated by the dashed lines in FIG. 3a, respectively; FIGS. 4 and 5 are diagrams of a heat sink of the exothermic electronic module as LED module according to the first and second embodiments of the present invention.
Detailed Description of the Embodiments
FIGS. 3a and 3b are diagrams of the exothermic electronic module as LED module according to the first embodiment of the present invention and an enlarged view of the part indicated by the dashed lines in FIG. 3a, respectively. Here the LED module is an example of the exothermic electronic module. It should be noted that the exothermic electronic module here is not limited to the lighting module. Also, the lighting module here is not limited to the LED module.
From FIGS. 3a and 3b. it can be seen that the LED module comprises an optical cover 9 and at least one exothermic body such as LED 1 disposed in the optical cover 9, a board 2 and a heat sink 3. Moreover, the board 2 can be a board with poor thermal conductivity, such as an FR-4 board.
Different from the prior art, the board 2 is opened with a cavity 4 through thickness of the board 2 in the vertical direction. Moreover, the heat sink 3, apart from a first portion 5 under the board 2 as in the prior art, is also provided with a second portion 6. Such second portion 6 which is similar to a convex is arranged in the cavity 4, such that the heat flow path between an LED 1 and the heat sink 3 is shortened. While at the same time, the design of the board will also be much easier, simpler and be low-cost. The LED 1 is disposed on the board 2 while the solder paste 11 and the copper layer 12 in the area between the LED 1 and the second portion 6 of the heat sink 3 are removed, instead, a thermal conductive insulation layer 7 is disposed between the LED 1 and the second portion 6 of the heat sink 3. The thermal conductive insulation layer 7 performs good thermal conductivity between the LED 1 and the second portion 6, as well as the insulation function between the LED 1 and the heat sink 3. Preferably, the thermal conductive insulation layer 7 can be a silicon elastomer, and also can be other thermal conductive insulation layer dispersed with silicon particles and also can be epoxy. Good thermal conductivity between the LED 1 and the heat sink 3 is further achieved thereby. For the different exothermic body, the thermal conductive insulation layer 7 may be replaced with the thermal conductive layer. In addition, similar to the prior art, a thermal conductive layer 8 is further disposed between the board 2 and the second portion 5 of the heat sink 3.
In the first embodiment the first portion 5 is integral with the second portion 6 of the heat sink 3, and the aluminum fins with low cost can be selected for the first portion 5 and the second portion 6, as shown in FIG. 4.
FIGS. 5 is a diagram of the heat sink of the LED module according to the second embodiment of the present invention. One difference between the heat sink of the LED module of the second embodiment from the heat sink of the LED module of the first embodiment according to the present invention, the first portion 5 and the second portion 6 are manufactured separately, with the second portion 6 being a heat pipe. The heat pipe can be pressed or soldered onto the aluminum material forming the first portion 5, such that good heat dissipation effect is further achieved.
Though the present invention is described in combination with exemplary embodiments currently regarded as practical, the person skilled in the art could understand that the present invention is not limited to the exemplary embodiments disclosed herein. Any modification, equivalent substitution, improvement, and etc., within the spirit and principle of the present invention, should be included within the scope of protection of the present invention.
Reference signs
1 LED
2 board
3 heat sink
4 cavity
5 first portion
6 second portion
7 thermal conductive insulation layer
8 thermal conductive layer
9optical cover
10 LED module
11 solder paste
12 copper layer
13 thermal conductive insulation layer