HEAT DISSIPATION DEVICE AND HEAT DISSIPATION FINS THEREOF

Abstract

A heat dissipation device for being in thermal contact with a heat source includes multiple heat dissipation fins, a heat pipe and a fan. Each of the heat dissipation fins includes a plate and an air guiding body. The plate has a thermal contact side used for being in thermal contact with the heat source. An acute angle is formed between an extension side of the air guiding body and the thermal contact side. The heat pipe penetrates through the plates. The fan used for forming an air current is installed at a side of the heat dissipation fin opposite to the thermal contact side. The air guiding body and the heat pipe are disposed in a flowing path of the air current. Thereby, the air current is guided toward the heat pipe and the amount of air flowing through the heat pipe is increased.

Description

This non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s) 201210442383.9. filed in China, P.R.C. on Nov. 1, 2012, the entire contents of which are hereby incorporated by reference.

TECHNICAL FIELD

The disclosure relates to a heat dissipation device, and more particularly to a fan structure and its blades.

BACKGROUND

As the technology in electronic field evolves, the efficiency of electronic components improves. However, the enhancement on the efficiency of electronic components causes the amount of heat produced to increase. The heat keeps accumulating in the electronic components and causes the temperatures of the electronic components to increase. The electronic components may crash or even burn up when the heat may not be removed effectively from the electronic components to lower the temperatures. Therefore, instead of working on enhancing the efficiency of electronic components, the problem the electronic industry faces is how to remove the heat generated from electronic components effectively.

Generally speaking, water-cooled heat dissipation device and air-cooled heat dissipation device are used to remove the heat produced by electronic components in the industry. The heat dissipation principle of water-cooled heat dissipation device refers to using air compressor or pump to drive the cooling fluid in the cooling pipe to exchange heat with the electronic components. Thereby, the heat of the electronic components may be removed. The heat dissipation principle of air-cooled heat dissipation device refers to using fan to guide cold air to flow through the electronic components in order to exchange heat and to remove the heat of the electronic components. Comparing to the water-cooled type, the air-cooled heat dissipation device is more cost-effective because air compressor, pump and cooling fluid are not required. Therefore, the air-cooled heat dissipation device is widely used in the industry to remove the heat of electronic components.

However, the conventional air-cooled heat dissipation device still cannot effectively remove the heat produced by high-end electronic components in the market. Therefore, considering cost-effectiveness and heat dissipation effect, it is highly demanded to develop air-cooled heat dissipation device with higher heat dissipation effect.

SUMMARY

An embodiment of the disclosure provides a heat dissipation device configured for being in thermal contact with a heat source. The heat dissipation device comprises a plurality of heat dissipation fins, a heat pipe and a fan. Each of the heat dissipation fins comprises a plate and an air guiding body. The plate has a thermal contact side configured for being in thermal contact with the heat source. The air guiding body is protruded from the plate. An acute angle is formed between an extension side of the air guiding body and the thermal contact side. The heat pipe penetrates through the plates and is kept away from the air guiding body at a distance. The fan is installed at a side of the heat dissipation fin opposite to the thermal contact side. The fan is configured for forming an air current. The air guiding body and the heat pipe are disposed in a flowing path of the air current. Thereby, the air current is guided toward the heat pipe and the amount of air flowing through the heat pipe is increased.

Another embodiment of the disclosure provides a heat dissipation fins configured for installing a fan and a heat pipe. The fan produces an air current. The heat dissipation fin comprises a plate and an air guiding body. The plate has a through hole for accommodating the heat pipe. The heat pipe is in thermal contact with the plate. The plate has an air outlet side. The air guiding body is protruded from the plate. The air guiding body is disposed in a flowing path of the air current, and an acute angle is formed between an extension side of the air guiding body and the thermal contact side. Thereby, the air current is guided toward the heat pipe and the amount of air flowing through the heat pipe is increased.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. It will be apparent, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are schematically shown in order to simplify the drawing.

FIG. 1 is a perspective view of a heat dissipation device according to an embodiment of the disclosure;

FIG. 2 is an exploded view of FIG. 1;

FIG. 3A is a plan view of a part of a heat dissipation fin in FIG. 1;

FIG. 3B is a plan view of a part of the heat dissipation fin according to another embodiment of the disclosure; and

FIG. 4 is an illustration of an air current of the heat dissipation device in FIG. 1.

DETAILED DESCRIPTION

In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. It will be apparent, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are schematically shown in order to simplify the drawing.

Please refer to FIGS. 1 to 3B. FIG. 1 is a perspective view of a heat dissipation device according to an embodiment of the disclosure. FIG. 2 is an exploded view of FIG. 1. FIG. 3A is a plan view of a part of a heat dissipation fin in FIG. 1. FIG. 3B is a plan view of a part of the heat dissipation fin according to another embodiment of the disclosure. A heat dissipation device 10 of this embodiment is in thermal contact with a heat source 30 through a heat conductive piece 20. In other words, the heat conductive piece 20 is disposed between the heat dissipation device 10 and the heat source 30. Moreover, the heat conductive piece 20 is in thermal contact with the heat dissipation device 10 and the heat source 30. In this embodiment and other embodiments, a layer of heat conductive adhesive 40 is further disposed between the heat conductive piece 20 and the heat source 30 for speeding up the transfer of the heat of the heat source 30 to the heat dissipation device 10. The heat conductive adhesive 40 is disposed between the heat conductive piece 20 and the heat source 30 in this embodiment. However, it should not be construed as a limitation to the disclosure. In other embodiments, heat conductive paste may be used in the heat dissipation device.

In this embodiment, the heat dissipation device 10 comprises a plurality of heat dissipation fins 100, a heat pipe 200 and a fan 300. Each of the heat dissipation fins 100 comprises a plate 110 and an air guiding body 120. The plate 110 has an air inlet side 111 and an air outlet side 112 disposed oppositely to each other as well as a side edge 113. The side edge 113 is connected with the air inlet side 111 and the air outlet side 112. The heat conductive piece 20 is disposed at the air outlet side 112 in order that the heat dissipation fins 100 are in thermal contact with the heat source 30 through the heat conductive piece 20. The plate 110 has a through hole 114. The heat pipe 200 is disposed inside the through hole 114 and is in thermal contact with the heat dissipation fin 100. The air guiding body 120 is protruded from the plate 110. An acute angle θ is formed between an extension side of the air guiding body 120 and a surface of the air outlet side 112. Thereby, the air guiding body 120 has the function for guiding air and the air guiding body 120 may also increase the heat dissipation area of the heat dissipation fins 100. Therefore, the heat dissipation effect of the heat dissipation fins 100 may be enhanced. Furthermore, the air guiding body 120 may be in an arc shape. That is, the air guiding body 120 may have a corner radius.

Furthermore, each of the heat dissipation fins 100 in this embodiment comprises the air guiding body 120. But it should not be construed as a limitation to the disclosure. In other embodiments, the heat dissipation fins 100 with and without the air guiding body 120 may be partially used in the heat dissipation device 10. For example, the heat dissipation fins 100 without the air guiding body 120 and the heat dissipation fins 100 with the air guiding body 120 are arranged alternatively.

The fan 300 is installed at the air inlet sides 111 of the heat dissipation fins 100. The fan 300 is used for forming an air current. The air current flows from the air inlet side 111 toward the air outlet side 112 of the plate 110. The air guiding body 120 and the heat pipe 200 are disposed in a flowing path of the air current. Therefore, the air guiding body 120 may guide the air current partially toward the heat pipe 200 and increase the amount of air flowing through the heat pipe 200. Thereby, the heat dissipation effect of the heat dissipation device 10 may be enhanced.

However, the heat dissipation effect of the heat dissipation device 10 may not be enhanced by protruding the air guiding body 120 at any location of the plate 110. Practically, the air guiding body 120 is required to dispose at a specific location. Thereby, the heat dissipation effect of the heat dissipation device 10 may be effectively enhanced.

Specifically, the heat pipe 200 and the air guiding body 120 in this embodiment are separated by a distance D. A connection line between a center of the heat pipe 200 and the center of the air guiding body 120 intersects with a flowing direction of the air current produced by the fan 300. Therefore, the air guiding body 120 may guide the air current by the heat pipe 200 to the heat pipe 200. Furthermore, the heat pipe 200 is disposed between the side edge 113 and the air guiding body 120. The air guiding body 120 has a first end 121 and a second end 122 disposed oppositely to each other as well as an air receiving side 123. The first end 121 is closed to the air inlet side 111. The second end 122 is closed to the air outlet side 112. A distance between the first end 121 of the air guiding body 120 and the side edge 113 is larger than that between the second end 122 of the air guiding body 120 and the side edge 113. Therefore, the acute angle θ is formed between the extension side of the air guiding body 120 and the surface of the air outlet side 112 as shown in FIG. 3A. Thereby, the air receiving side 123 of the air guiding body 120 faces the air inlet side 111 and the heat pipe 200. The distance mentioned herein between the heat pipe 200 and the air guiding body 120 refers to the distance D between the center of the heat pipe 200 and the first end 121 of the air guiding body 120. The distance D is preferably to be between 5 mm and 30 mm. Additionally, the acute angle θ mentioned herein is preferably to be between 15 and 75 degrees.

In this embodiment, the heat pipe 200 is disposed between the side edge 113 and the air guiding body 120. However, it should not be construed as a limitation to the disclosure. In other embodiments, the air guiding body 120 may be disposed between the heat pipe 200 and the side edge 113. Specifically, in this embodiment, a distance between the first end 121 of the air guiding body 120 and the side edge 113 is shorter than that between the second end 122 of the air guiding body 120 and the side edge 113. Therefore, the acute angle θ is formed between the extension side of the air guiding body 120 and the surface of the air outlet side 112 as shown in FIG. 3B. Thereby, the air receiving side 123 of the air guiding body 120 faces the air inlet side 111 and the heat pipe 200.

Please refer to FIG. 4. FIG. 4 is an illustration of the air current of the heat dissipation device in FIG. 1. When the air current produced by the fan 300 flows along an air entering direction a from the air inlet side 111 of the plate 110 to the air outlet side 112 in contact with the heat source 30, the air current flows through the heat pipe 200 and the air guiding body 120. Specifically, the air current flows through the heat pipe 200 and the air guiding body 120 because the arranged directions of the heat pipe 200 and the air guiding body 120 are roughly perpendicular to the air entering direction a. However, since the air current is partially blocked by the air receiving side 123 of the air guiding body 120, the air current is guided to the heat pipe 200 disposed by the air guiding body 120. Thereby, the amount of air flowing through the heat pipe 200 in a unit of time is increased substantially. Specifically, the temperature of the heat pipe 200 should be higher than that of the nearby heat dissipation fins 100. Thus, the disposition of the air guiding body 120 guides the air current near the heat pipe 200 to intensively flow toward the heat pipe 200 with a higher temperature. Therefore, the heat pipe 200 may exchange heat with a large amount of air current first which helps to remove the heat earlier. Thereby, the heat dissipation efficiency of the heat dissipation device 10 may be enhanced.

Please refer to List 1. List 1 shows results of tests under the conditions that the rotation speed of the fan 300 is at 4300 rpm, the voltage of the fan is 12V, and the thermal power produced by the heat source 30 is 150 watts. List 1 shows that the measured temperatures of the heat source 30 when the heat dissipation fins 100 are equipped with the air guiding body 120 are lower than the measured temperatures of the heat source 30 when the heat dissipation fins 100 are not equipped with the air guiding body 120. In this embodiment, the highest dissipation temperature (namely, the most amount of the temperature dropped in this embodiment) is measured when the acute angle θ between the extension side of the air guiding body 120 and the surface of the air outlet side 112 is 30 degrees.

List 1 shows the relationship between the acute angle θ (between the extension side of the air guiding body 120 and the surface of the air outlet side 112) and the dissipated temperature (namely, temperature dropped).

			Temp-
			erature
			of Heat
	Ratio of	Temperature of	Source	Dissipated
	Increased	Heat Source	with Air	Temperature
	Dissipation	without Air	Guiding	(temperature
	Area	Guiding Body	Body	dropped)
θ = 30 degrees	3.24%	88.1° C.	81.4° C.	6.7° C.
θ = 45 degrees	4.84%	86.1° C.	82.5° C.	3.6° C.
θ = 30 degrees	1.7%	95.5° C.	90.6° C.	4.9° C.
and corner
radius = 20

According to the heat dissipation device and its heat dissipation fins disclosed in the disclosure, by disposing an acute angle between the extension side of the air guiding body and the surface of the air outlet side, the air receiving side of the air guiding body may face the air inlet side and the heat pipe. Therefore, when the air current flows from the air inlet side, the air current is guided by the air guiding body and will flow intensively toward the heat pipe. Thereby, the amount of air flowing through the heat pipe in a unit of time is increased, and thus improves the heat dissipation efficiency of the heat dissipation device.

Claims

1. A heat dissipation device configured for being in thermal contact with a heat source, the heat dissipation device comprising:

a plurality of heat dissipation fins, each of some of the heat dissipation fins comprising a plate and an air guiding body, the plate having an air outlet side configured for being in thermal contact with the heat source, the air guiding body being protruded from the plate, an acute angle being formed between an extension side of the air guiding body and a surface of the air outlet side;

a heat pipe penetrating through the plates and the heat pipe being kept away from the air guiding body at a distance; and

a fan installed at a side of the heat dissipation fins opposite to the air outlet side, the fan being configured for forming an air current, and the air guiding body as well as the heat pipe being disposed in a flowing path of the air current to guide the air current toward the heat pipe and to increase an amount of air flowing through the heat pipe.

2. The heat dissipation device as claimed in claim 1, wherein the acute angle is between 15 and 75 degrees.

3. The heat dissipation device as claimed in claim 1, wherein the plate has an air inlet side and a side edge, the air current flows from the air inlet side toward the air outlet side, the side edge is connected with the air inlet side and the air outlet side, the air guiding body has a first end and a second end disposed oppositely to each other, the first end is close to the air inlet side, the second end is close to the air outlet side, the heat pipe is disposed between the side edge and the air guiding body, a distance between the first end of the air guiding body and the side edge is larger than that between the second end of the air guiding body and the side edge.

4. The heat dissipation device as claimed in claim 1, wherein the plate has an air inlet side and a side edge, the air current flows from the air inlet side toward the air outlet side, the side edge is connected with the air inlet side and the air outlet side, the air guiding body has a first end and a second end disposed oppositely to each other, the first end is close to the air inlet side, the second end is close to the air outlet side, the air guiding body is disposed between the side edge and the heat pipe, a distance between the first end of the air guiding body and the side edge is shorter than that between the second end of the air guiding body and the side edge.

5. The heat dissipation device as claimed in claim 1, wherein a connection line between a center of the air guiding body and a center of the heat pipe intersects with a flowing direction of the air current.

6. A heat dissipation fin configured for installing a fan and a heat pipe, the fan producing an air current, the heat dissipation fin comprising:

a plate having a through hole configured for accommodating the heat pipe, the heat pipe being in thermal contact with the plate, the plate having an air outlet side; and

an air guiding body protruded from the plate, the air guiding body being disposed in a flowing path of the air current, and an acute angle being disposed between an extension side of the air guiding body as well as a surface of the air outlet side in order to guide the air current toward the heat pipe and to increase an amount of air flowing through the heat pipe.

7. The heat dissipation fin as claimed in claim 6, wherein the acute angle is between 15 and 75 degrees.

8. The heat dissipation fin as claimed in claim 6, wherein the plate has an air inlet side and a side edge, the air current flows from the air inlet side toward the air outlet side, the side edge is connected with the air inlet side and the air outlet side, the air guiding body has a first end and a second end disposed oppositely to each other, the first end is close to the air inlet side, the second end is close to the air outlet side, the heat pipe is disposed between the side edge and the air guiding body, a distance between the first end of the air guiding body and the side edge is longer than that between the second end of the air guiding body and the side edge.

9. The heat dissipation fin as claimed in claim 6, wherein the plate has an air inlet side and a side edge, the air current flows from the air inlet side toward the air outlet side, the side edge is connected with the air inlet side and the air outlet side, the air guiding body has a first end and a second end disposed oppositely to each other, the first end is close to the air inlet side, the second end is close to the air outlet side, the air guiding body is disposed between the side edge and the heat pipe, a distance between the first end of the air guiding body and the side edge is shorter than that between the second end of the air guiding body and the side edge.