US20170176113A1

US20170176113A1 - Heat Sink and Case Having the Same

Info

Publication number: US20170176113A1
Application number: US15/204,578
Authority: US
Inventors: Chiu-Lang Lin; Li-Chen Hsieh
Original assignee: Morningrich Technology Co Ltd
Current assignee: Morningrich Technology Co Ltd
Priority date: 2015-12-17
Filing date: 2016-07-07
Publication date: 2017-06-22
Also published as: TWM520790U

Abstract

A heat sink adapted to dissipate heat from a heat source includes a heat dissipating unit that includes at least one deformation portion protruding toward the heat source, and a reflective surface formed on the deformation portion and facing the heat source for reflecting radiant heat from the heat source. A case including the heat sink is also disclosed.

Description

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority of Taiwanese Utility Model Application Number 104220238, filed on Dec. 17, 2015.

FIELD

The disclosure relates to a heat sink adapted for heat dissipation from a heat source, and a case having the heat sink.

BACKGROUND

Referring to FIG. 1, a conventional heat sink 1 is shown to include a main body 11, and a plurality of fins 12 extending away from the main body 11. The heat sink 1 is adapted for heat dissipation when contacting a heat source 2. Specifically, heat from the heat source 2 is transferred to the main body 11 of the heat sink 1 via conduction and then dissipated into the air through the fins 12.
Recently, trends seem to favor electronic products that are relatively thinner and have faster computing speeds. Thus, electronic components within the electronic product must be miniaturized to accommodate for the thinner design, resulting in relatively high heat density associated with the electronic components.
However, simply using the heat sink 1 that relies on dissipating heat from the heat source 2 via conduction is not adequate for heat dissipation of the electronic products. Specifically, solely relying on the contact area between the fins 12 and the air for heat dissipation via conduction is inadequate to reach a sufficient cooing effect. Moreover, when the heat transfer rate is low to the point that heat emitted by the heat source 2 cannot be quickly dissipated, the result is that the temperature of the heat sink 1 rises to a level where the heat sink 1 is unable to sustain heat dissipation from the heat source 2.
Therefore, in order to meet the current demands of increasingly thinner electronic products, as well as electronic products that require faster computing speeds, proper heat dissipation when utilizing these electronic products containing electronic components with high heat density is warranted. For these reasons, in addition to dissipation of heat via conduction, the ability for the conventional heat sink 1 to also dissipate heat via radiation would provide an improved cooling solution to greatly enhance the effect of heat dissipation.

SUMMARY

Therefore, an object of the present disclosure is to provide a heat sink that can alleviate at least one of the drawbacks associated with the prior art.
According to one aspect of the present disclosure, a heat sink adapted to dissipate heat from a heat source includes a heat dissipating unit that includes at least one deformation portion protruding toward the heat source, and a reflective surface formed on the deformation portion and facing the heat source for reflecting radiant heat from the heat source.
According to another aspect of the present disclosure, a case adapted to dissipate heat from a heat source includes a housing and the aforementioned heat sink adhered to the housing.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the disclosure will become apparent in the following detailed description of the embodiments with reference to the accompanying drawings, of which:

FIG. 1 is a side view of a conventional heat sink in contact with a heat source;

FIG. 2 is a partly schematic view of a first embodiment of a heat sink according to the present disclosure that is disposed for being near a heat source;

FIG. 3 is a schematic view of the first embodiment;

FIG. 4 is a fragmentary and partly schematic view of a second preferred embodiment of the heat sink according to the present disclosure;

FIG. 5 is a schematic view of the second embodiment;

FIG. 6 is a side view illustrating a variation of a heat dissipating body included in each of the first and second embodiments;

FIG. 7 is a fragmentary schematic view of an embodiment of a case according to the present disclosure that is disposed separately from a heat source mounted on a circuit board;

FIG. 8 a fragmentary schematic view of a variation of the embodiment of the case shown in FIG. 7, in which the case is in contact with the heat source mounted on the circuit board;

FIG. 9 is a fragmentary schematic view of a further embodiment of the case according to the present disclosure that is disposed separately from the heat source mounted on the circuit board; and

FIG. 10 is a fragmentary schematic view of a variation of the further embodiment of the case shown in FIG. 9, in which the case is in contact with the heat source mounted on the circuit board.

DETAILED DESCRIPTION

Before the disclosure is described in greater detail, it should be noted that where considered appropriate, reference numerals or terminal portions of reference numerals have been repeated among the figures to indicate corresponding or analogous elements, which may optionally have similar characteristics.
Referring to FIGS. 2 and 3, a first embodiment of a heat sink 3 adapted to dissipate heat from a heat source 4 according to the present disclosure is shown to include a heat dissipating unit, a transparent insulating unit 33, an adhesive layer 34, and a release liner 35.
The heat dissipating unit includes at least one deformation portion 311 protruding toward the heat source 4, a reflective surface 312 formed on the deformation portion 311, and a securing surface 315 opposite to the reflective surface 312.
The reflective surface 312 faces the heat source 4, and is made of a thermally reflective material for reflecting radiant heat from the heat source 4. The reflective surface 312 includes a deformation region 314 covering the deformation portion 311 and a surrounding region 313 surrounding the deformation region 314 and the deformation portion 311. The deformation portion 311 may have a cross section that may be shaped as one of a circle, an oval, and a polygon. It should be noted that the deformation portion 311 is preferably made by stamp pressing, but may also be formed via other methods, and thus, what is disclosed herein should not be imposed as an implementation limitation.
In this embodiment, the heat dissipating unit includes a heat dissipating body 31 that includes the deformation portion 311 and the opposite reflective and securing surfaces 312, 315, and is made of a metal material, e.g., gold, silver, copper, aluminum, or combinations thereof. It should be noted that the material of the heat dissipating body 31 should not be limited to what is disclosed herein, and in practice, any material with a relatively high coefficient of thermal conductivity may be suitable for the production of the heat dissipating body 31.
In this embodiment, since the heat dissipating body 31 is made of the aforesaid metal material, the reflective surface 312 may be formed by polishing a surface of the heat dissipating body 31. Directly polishing the surface of the heat dissipating body 31 offers a streamlined approach to forming of the reflective surface 312. It should be noted that if the material of the heat dissipating body 31 is gold or copper, the reflective surface 312 may have a yellow or red luster, respectively.
The adhesive layer 34 is disposed on and adhered to the securing surface 315 of the heat dissipating unit.
The release liner 35 is adhered to the adhesive layer 34 and is disposed opposite to the heat dissipating unit with respect to the adhesive layer 34. In this embodiment, the release liner 35 includes a separation portion 351 aligned with the deformation portion 311, and a tear-off portion 352 surrounding the separation portion 351 that can be peeled to expose the adhesive layer 34 for adhering the heat dissipating unit to an object. In other words, when the heat sink is to be adhered to an object, the tear-off portion 352 can be peeled so that the heat sink 3 can adhere to the object through the adhesive layer 34. The adhesive layer 34 is made of an organic polymeric material which is thermally stable, and thus the adhesive layer 34 is unlikely to lose its adhesive strength from absorption of heat energy.
The transparent insulating unit 33 is disposed on the reflective surface 312 and faces the heat source 4. The transparent insulating unit 33 includes an electrically insulating film 332 and a glue film 331 disposed between the electrically insulating film 332 and the reflective surface 312 for adhering the electrically insulating film 332 to the reflective surface 312. When the heat dissipating body 31 that includes the deformation portion 311 is made of the aforesaid metal material, an electronic product that uses the heat sink 3 can be protected from short circuiting by virtue of the transparent insulating unit 33. It should be noted that the transparency of the transparent insulating unit 33 helps to avoid affecting the reflection of radiant heat by the reflective surface 312.
Therefore, the deformation portion 311 of the heat dissipating body 31 and the reflective surface 312 that is formed on the deformation portion 311 of the heat dissipating body 31 are able to effectively reflect and dissipate heat radiating from the heat source 4. Furthermore, the metal material, e.g., gold, silver, copper, aluminum, or combinations thereof, of the heat dissipating body 31 has a high coefficient of thermal conductivity and thus provides good heat conductivity for enhanced heat dissipation. In these ways, the heat sink 3 effectively dissipates heat from the heat source 4 through conduction and radiation.
Referring to FIGS. 4 and 5, a second embodiment of the heat sink 3 according to the present disclosure is nearly identical to the first embodiment, but differs from the first embodiment in that the heat dissipating unit of the second embodiment further includes a reflective layer 36 that has the reflective surface 312.
In this embodiment, the heat dissipating body 31 that includes the deformation portion 311 may be made of one of a metal material, e.g., nickel or chromium, and a material exhibiting electrical conductivity and thermal anisotropy, e.g., graphite. As such, the reflective layer 36 may be formed on the heat dissipating body 31 by electroplating techniques.
When the reflective layer 36 that has the reflective surface 312 is made of nickel or chromium, the reflective surface 312 may exhibit a silver appearance. Unlike the first embodiment, in which the yellow or red luster of the reflective surface 312 due to direct polishing of the heat dissipating body 31 made of gold or copper, respectively, may result in the absorption of certain wavelengths of light, the silver appearance of the reflective surface 312 of the second embodiment minimizes the absorption of certain wavelengths of light and thus effectively enhances the reflection of radiant heat by the reflective surface 312.
Alternatively, the heat dissipating body 31 that includes the deformation portion 311 may be made of a polymeric material. In that case, due to the fact that the polymeric material has low electrical conductivity, the reflective layer 36 that has the reflective surface 312 may be formed on the heat dissipating body 31 by sputtering techniques.
With reference to FIG. 4, in this embodiment, the heat dissipating unit further includes an under-plate layer 32 that is interposed between the heat dissipating body 31 and the reflective layer 36. The under-plate layer 32 which may be made of the same material as the heat dissipating body 31 can effectively fill cavities formed on the heat dissipating body 31, so that the heat dissipating body 31 can have a smooth surface upon electroplating of the reflective layer 36.
Referring to FIG. 6, in each of the embodiments, the heat dissipating body 31 may include a plurality of deformation portions 311.
The aforesaid heat sink 3 of the disclosure may be used to form a case which is adapted to dissipate heat from a heat source 4 mounted on, e.g., a circuit board 9.
Referring to FIG. 7, an embodiment of a case according to this disclosure includes a housing 5 and the heat sink 3 of the first embodiment (shown in FIG. 3) which is adhered to the housing 5. In particular, the heat sink 3 is adhered to the housing 5 through the adhesive layer 34 that is exposed from the release liner 35 by peeling the tear-off portion 352. An instance of using the case to house an electronic product (only a part thereof is shown in FIG. 7) is presented herein for illustrating the heat dissipation effect.
In this embodiment, the heat sink 3 is spaced apart from the heat, source 4,and the deformation portion 311 has a first face protruding toward and facing the heat source 4, and a second face opposite to the first face and concavely indented toward the first face. As such, the heat sink 3 also has a first side protruding toward and facing the heat source 4, and a second side opposite to the first side and concavely indented toward the first side. As such, an air gap 316 exists between and is defined by a surface of the housing 5 that faces the heat sink 3 and a part of the second side of the heat sink 3 which is corresponding in position to the deformation portion 311. Through the incorporation of the air gap 316 that has a lower coefficient of thermal conductivity as compared to that of the heat dissipating body 31, an effect of slowing the transfer of heat via conduction to the housing 5 may be achieved.
In this embodiment, the reflective surface 312 formed on the deformation portion 311 faces the heat source 4 and reflects radiant heat from the heat source 4 so that the heat energy is not easily transferred to the housing 3 of the case. Thus, a good heat insulation effect is achieved, and a user who carries an electronic product that utilizes the case would hardly be affected by the aforementioned heat energy. Furthermore, since some of the radiant heat reflected by the reflective surface 312 may stay in a space between the heat sink 3 and the heat source 4, a heat dissipation mechanism, e.g., a heat dissipation fan, may be implemented for faster dissipation of the radiant heat.
In these ways, the heat sink 3 may efficiently dissipate heat from the heat source 4 having high heat energy density associated with modern electronic products and is thus able to promote excellent heat insulation effects and comfort of use for the user.
It should also be noted that since the heat dissipating body 31 of the heat sink 3 may be made of the metal material, the heat dissipating body 31 is able to offer a good masking effect against electromagnetic waves generated by electronic products, e.g., communication equipment, and minimize negative health effects associated with the electromagnetic waves.
FIG. 8 illustrates a variation of the embodiment of the case shown in FIG. 7. Referring to FIG. 8, in this variation, the case is disposed in contact with the heat source 4. As such, heat energy generated by the heat source 4 can be transferred directly to the heat sink 3 via conduction. In this way, the conductive property of the heat dissipating body 31 is properly utilized to dissipate heat from the heat source 4.
Furthermore, in this variation, a plurality of electronic components 41 may also be mounted on the circuit board 9 and are spaced apart from the reflective surface 312 of the heat substrate 3 such that radiant heat emitted from the electronic components 41 can be reflected by the reflective surface 312 for heat dissipation. In this variation, the dissipation of heat may occur by both conduction and radiation such that heat dissipation by the heat sink 3 can be effectively enhanced.
Referring to FIG. 9, a further embodiment of the case according to the present disclosure is nearly identical to the embodiment shown in FIG. 7, but differs in that the heat dissipating unit used in this further embodiment is the one shown in FIG. 5. In addition to achieving the same heat dissipation effects as the embodiment shown in FIG. 7, the reflective layer 36 which may be made of nickel or chromium allows the reflective surface 312 to have a silver appearance and thus minimize the absorption of certain wavelengths of light and effectively enhance the reflection of radiant heat by the reflective surface 312.
FIG. 10 illustrates a variation of the further embodiment of the case shown in FIG. 9. Referring to FIG. 10, in this variation, the case is disposed in contact with the heat source 4. As such, heat energy generated by the heat source 4 can be transferred directly to the heat sink 3 via conduction. In this way, the conductive property of the heat dissipating body 31 is properly utilized to dissipate heat from the heat source 4.
Furthermore, in this variation, a plurality of electronic components 41 may also be mounted on the circuit board 9 and are spaced apart from the reflective surface 312 of the heat substrate 3 such that radiant heat emitted from the electronic components 41 can be reflected by the reflective surface 312 for heat dissipation. In this variation, the dissipation of heat may occur by both conduction and radiation such that heat dissipation by the heat sink 3 can be effectively enhanced.
In summary, the at least one deformation portion 311 and the reflective surface 312 formed on the deformation portion 311 of the heat sink 3 according to the present disclosure effectively reflect and disperse radiant heat from the heat source 4. Furthermore, due to the conductive property of the heat dissipating body 31 of the heat dissipating unit, heat can also be dissipated via conduction.
Moreover, the case which includes the housing 5 and the heat sink 3 adhered to the housing 5, is highly suitable for dissipating heat from the heat source 4 having high heat energy density by virtue of the reflective surface 312 that is able to reflect radiant heat from the heat source 4. In these ways, the object of this disclosure can be achieved.
In the description above, for the purposes of explanation, numerous specific details have been set forth in order to provide a thorough understanding of the embodiment(s). It will be apparent, however, to one skilled in the art, that one or more other embodiments may be practiced without some of these specific details. It should also be appreciated that reference throughout this specification to “one embodiment,” “an embodiment,” an embodiment with an indication of an ordinal number and so forth means that a particular feature, structure, or characteristic may be included in the practice of the disclosure. It should be further appreciated that in the description, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of various inventive aspects.
While the disclosure has been described in connection with what is (are) considered the exemplary embodiment(s), it is understood that this disclosure is not limited to the disclosed embodiment(s) but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.

Claims

What is claimed is:

1. A heat sink adapted to dissipate heat from a heat source, said heat sink comprising:

a heat dissipating unit that includes at least one deformation portion protruding toward the heat source, and a reflective surface formed on said deformation portion and facing the heat source for reflecting radiant heat from the heat source.

2. The heat sink as claimed in claim 1, wherein said heat dissipating unit includes a heat dissipating body that is made of a metal material and that includes the deformation portion.

3. The heat sink as claimed in claim 2, wherein the metal material is selected from the group consisting of gold, silver, copper, aluminum, and combinations thereof.

4. The heat sink as claimed in claim 2, wherein said reflective surface is formed by polishing a surface of said heat dissipating body.

5. The heat sink as claimed in claim 1, wherein said heat dissipating unit includes a heat dissipating body that includes the deformation portion and that is made of one of a metal material and a material exhibiting electrical conductivity and thermal anisotropy.

6. The heat sink as claimed in claim 5, wherein said heat dissipating unit further includes a reflective layer that has said reflective surface and that is formed on said heat dissipating body by electroplating techniques.

7. The heat sink as claimed in claim 6, wherein said reflective layer is made of nickel or chromium.

8. The heat sink as claimed in claim 6, wherein said heat dissipating unit further includes an under-plate layer interposed between said heat dissipating body and said reflective layer.

9. The heat sink as claimed in claim 1, wherein said heat dissipating unit includes a heat dissipating body that includes the deformation portion and that is made of a polymeric material.

10. The heat sink substrate as claimed in claim 9, wherein said heat dissipating unit further includes a reflective layer that has said reflective surface and that is formed on said heat dissipating body by sputtering techniques.

11. The heat sink substrate as claimed in claim 1, wherein said reflective surface includes a deformation region covering said deformation portion and a surrounding region surrounding said deformation region and said deformation portion.

12. The heat sink as claimed in claim 1, further comprising a transparent insulating unit disposed on said reflective surface of said heat dissipating unit and facing the heat source.

13. The heat sink as claimed in claim 12, wherein said transparent insulating unit includes an electrically insulating film and glue film disposed between said electrically insulating film and said reflective surface for adhering said electrically insulating film to said reflective surface.

14. The heat sink as claimed in claim 1, further comprising an adhesive layer disposed on and adhered to a securing surface of said heat dissipating unit opposite to said reflective surface.

15. The heat sink as claimed in claim 14, further comprising a release liner adhered to said adhesive layer opposite to said heat dissipating unit.

16. The heat sink substrate as claimed in claim 15, wherein said release liner includes a separation portion aligned with said deformation portion, and a tear-off portion surrounding said separation portion and being peeled to expose said adhesive layer for adhering said heat dissipating unit to an object.

17. The heat sink as claimed in claim 1, wherein said deformation portion has a cross section that is shaped as one of a circle, oval, and polygon.

18. A case adapted to dissipate heat from a heat source, comprising:

a housing; and

said heat sink of claim 1, adhered to said housing.

19. The case as claimed in claim 18, wherein said deformation portion of said heat sink is spaced apart from said housing.

20. The case as claimed in claim 18, wherein said heat sink is disposed for being in contact with the heat source.