WO2024239312A1

WO2024239312A1 - Radiator and electronic device

Info

Publication number: WO2024239312A1
Application number: PCT/CN2023/096257
Authority: WO
Inventors: Xiu SHI; Wei Zhang; Zhenzhen LIU; Xiaodong Tang
Original assignee: Telefonaktiebolaget LM Ericsson AB
Current assignee: Telefonaktiebolaget LM Ericsson AB
Priority date: 2023-05-25
Filing date: 2023-05-25
Publication date: 2024-11-28
Anticipated expiration: 2025-11-25

Abstract

The present disclosure is related to a radiator and an electronic apparatus. The radiator includes a heat sink cover and a radiator including at least one evaporator, a condenser and a connection part. The heat sink cover has a first face and a second face in opposite to the first face, and is configured to at least partly connect to and contact the electronic device on the first face so as to dissipate heat from the electronic device. The heat sink cover is provided with at least one window to expose at least one of first heat sources of the electronic device. The at least one evaporator, on the second face, contacts the at least one of the first heat sources of the electronic device, through the at least one window of the heat sink cover.

Description

RADIATOR AND ELECTRONIC DEVICE

Technical Field

The present disclosure is related to the field of cooler, and in particular, to a radiator and an electronic device.

Background

With electronic component power consumption increasing, the traditional air cooling method is facing challenge. For example, the next generation switch chip used in current electronic product will come to several hundred watts on a single chip. This power consumption level exceeds the cooling capacity of current air cooling method with local heat sink solution.

On the other hand, the whole society is advocating energy saving and emission reduction. Designers are trying every possible to limit the power consumption of the developing products.

At present, most of baseband and transport products have a plurality of heat/power sources, which generate lots of heat during operation. There is urgent need for a cooling method which has a high cooling capacity and better cooling efficiency, while the volume of the product would not be enlarged significantly and even could maintain compaction. Liquid cooling is recognized in the industry as an advanced cooling method which has both the merits.

However, a device involving liquid cooling in prior art still does not sufficiently meet requirements of the rapid development of the electronic device.

Summary

According to a first aspect of the present disclosure, assembly for dissipating heat from an electronic device is provided. The assembly includes:

a heat sink cover having a first face and a second face in opposite to the first face, the heat sink cover being configured to at least partly connect to and contact the electronic device on the first face so as to dissipate heat from the electronic device, and

a radiator, at least part of the radiator being mounted on the second face of the heat sink cover;

wherein the radiator comprises:

at least one evaporator configured to absorb heat from the electronic device and evaporate a liquid working fluid to a gaseous working fluid therein;

a condenser configured to condense the gaseous working fluid from the at least one evaporator; and

a connection part between the at least one evaporator and the condenser;

wherein the heat sink cover is provided with at least one window to expose at least one of first heat sources of the electronic device, and

the at least one evaporator contacts the at least one of the first heat sources of the electronic device, through the at least one window of the heat sink cover.

In some embodiments, at least part of the first face of the heat sink cover contacts at least one second heat source of the electronic device.

In some embodiments, the at least one evaporator includes two or more evaporators, and the two or more evaporators are communicated independently to the condenser from each other.

In some embodiments, the at least one evaporator each comprises an evaporator main body defining a first evaporator cavity, and a protruded part protruding from the evaporator main body and having a flat surface, such that the flat surface contacts the at least one of the first heat sources during operation,

wherein the protruded part defines a second evaporator cavity and the first evaporator cavity is communicated to the second evaporator cavity.

In some embodiments, the at least one evaporator each comprises an evaporator flange configured to be mounted on inner perimeter of the at least one window so that the at least one window is covered after installing the at least one evaporator.

In some embodiments, a gasket is provided between the evaporator flange and the inner perimeter of the at least one window.

In some embodiments, an interface material is provided between the flat surface of the protruded part and the at least one of first heat sources.

In some embodiments, the evaporator flange is mounted on the heat sink cover by a screw and a spring, wherein the screw is screwed in a screw hole of the heat sink cover, and the spring is provided to surround the screw and between the screw and screw hole, so as to contact and press the flange towards the gasket.

In some embodiments, the condenser is isolated from the electronic device by the heat sink cover.

In some embodiments, the second face of the heat sink cover is provided with heat sink cover fins.

In some embodiments, the assembly includes a fan configured adjacent to the heat sink cover and the condenser at a first side, between the first face and the second face, of the heat sink cover, so as to draw air from a second side of the heat sink cover via the heat sink cover fins of the heat sink cover towards the condenser, the second side being opposite to the first side.

In some embodiments, the heat sink cover fins are arranged so that a space between adjacent two of the heat sink cover fins opens towards the fan, such that the drawn air passes through the space.

In some embodiments, the at least one evaporator each comprises a raised portion protruding from the evaporator main body and defining a third evaporator cavity, the raised portion being opposite to the protruded part with respect to the evaporator main body,

wherein the third evaporator cavity is communicated to the first evaporator cavity, so that the first evaporator cavity together with the third evaporator cavity and the second evaporator cavity form a whole evaporator cavity.

In some embodiments, the raised portion comprises an evaporator outlet configured to output working fluid to the condenser,

wherein the evaporator main body comprises an evaporator inlet configured to intake the working fluid from the condenser.

In some embodiments, the condenser comprises a condenser main body defining a first condenser cavity, and at least one dropped portion defining a second condenser cavity at a level lower than that of the first condenser cavity, the first condenser cavity having a volume larger than that of the second condenser cavity and communicating with the second condenser cavity to constitute a whole condenser cavity.

In some embodiments, the condenser main body comprises at least one condenser inlet configured to intake the working fluid from the at least one evaporator respectively to the first condenser cavity, and the at least one dropped portion comprises at least one condenser outlet configured to output the working fluid from the second condenser cavity to the evaporator main body of the at least one evaporator, via the evaporator inlet.

In some embodiments, the condenser main body comprises a base, and internal fins therein disposed on upper face of the base; and

the condenser further comprises external fins disposed on lower face of the base, outside of the first condenser cavity.

In some embodiments, the base comprises an elongated through hole configured to communicate the first condenser cavity with the second condenser cavity.

In some embodiments, the assembly further comprises a top cover configured to connect to the first face of the heat sink cover, sealing the electronic device therebetween.

In some embodiments, the assembly further comprises a bottom cover configured to couple to the heat sink cover, so that the bottom cover and the heat sink cover define an air flowing path between the bottom cover and the heat sink cover.

In some embodiments, the assembly further comprises a fan tray coupled to and abutting against the first side of the heat sink cover, wherein the fan is mounted in the fan tray.

According to a second aspect of the present disclosure, an electronic apparatus comprising the assembly of the first aspect is provided.

Brief Description of the Drawings

The foregoing and other features of the present disclosure will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. Understanding that these drawings depict only several embodiments in accordance with the disclosure and therefore are not to be considered limiting of its scope, the disclosure will be described with additional specificity and detail through use of the accompanying drawings.

FIG. 1A is a figure illustrating an exemplary assembly for dissipating heat from an electronic device according to an embodiment of the present disclosure.

FIG. 1B is a figure illustrating the exemplary assembly for dissipating heat from an electronic device in FIG. 1A according to an embodiment of the present disclosure, in which the assembly is reversed so that the bottom cover faces upwards.

FIG. 2 (a) is an exploded view illustrating an exemplary assembly for dissipating heat from an electronic device according to an embodiment of the present disclosure, in which a top cover is removed for exposing the heat sink cover and the radiator, and FIG. 2 (b) illustrates the radiator used in the assembly.

FIG. 3 is a view illustrating an exemplary radiator in operation state in the assembly in FIG. 2 (b) according to an embodiment of the present disclosure.

FIG. 4 is an exploded view illustrating an exemplary condenser of the radiator according to an embodiment of the present disclosure.

FIG. 5 is a figure illustrating an assembly for dissipating heat from an electronic device according to an embodiment of the present disclosure, in which a top cover is removed for exposing the heat sink cover and the radiator, and the radiator has been mounted on the heat sink cover.

FIG. 6 is a cross section view illustrating an exemplary assembly in operation arrangement according to another embodiment of the present disclosure.

FIG. 7 is a schematic cross section view illustrating an exemplary evaporator of the radiator according to still another embodiment of the present disclosure.

FIG. 8 illustrates a condenser of the radiator according to an embodiment of the present disclosure, in which external fins are removed for clarity.

Detailed Description

Hereinafter, the present disclosure is described with reference to embodiments shown in the attached drawings. However, it is to be understood that those descriptions are just provided for illustrative purpose, rather than limiting the present disclosure. Further, in the following, descriptions of known structures and techniques are omitted so as not to unnecessarily obscure the concept of the present disclosure.

Those skilled in the art will appreciate that the term “exemplary” is used herein to mean “illustrative, ” or “serving as an example, ” and is not intended to imply that a particular embodiment is preferred over another or that a particular feature is essential. Likewise, the terms “first” , “second” , “third” , “fourth, ” and similar terms, are used simply to distinguish one particular instance of an item or feature from another, and do not indicate a particular order or arrangement, unless the context clearly indicates otherwise.

Conditional language used herein, such as "can, " "might, " "may, " "e.g., " and the like, unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments comprise, while other embodiments do not comprise, certain features, elements and/or states. Thus, such conditional language is not generally intended to imply that features, elements and/or states are in any way required for one or more embodiments or that one or more embodiments necessarily comprise logic for deciding, with or without author input or prompting, whether these features, elements and/or states are comprised or are to be performed in any particular embodiment. Also, the term "or" is used in its inclusive sense (and not in its exclusive sense) so that when used, for example, to connect a list of elements, the term "or" means one, some, or all of the elements in the list. Further, the term "each, " as used herein, in addition to having its ordinary meaning, can mean any subset of a set of elements to which the term "each" is applied.

The term “based on” is to be read as “based at least in part on. ” The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment. ” The term “another embodiment” is to be read as “at least one other embodiment. ” Other definitions, explicit and implicit, may be comprised below. In addition, language such as the phrase "at least one of X, Y and Z, " unless specifically stated otherwise, is to be understood with the context as used in general to convey that an item, term, etc. may be either X, Y, or Z, or a combination thereof.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limitation of example embodiments. As used herein, the singular forms “a” , “an” , and “the” are intended to comprise the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” , “comprising” , “has” , “having” , “comprises” and/or “including” , when used herein, specify the presence of stated features, elements, and/or components etc., but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof. It will be also understood that the terms “connect (s) , ” “connecting” , “connected” , etc. when used herein, just mean that there is an electrical or communicative connection between two elements and they can be connected either directly or indirectly, unless explicitly stated to the contrary.

Of course, the present disclosure may be carried out in other specific ways than those set forth herein without departing from the scope and essential characteristics of the disclosure.

Although a plurality of embodiments of the present disclosure will be illustrated in the accompanying drawings and described in the following Detailed Description, it should be understood that the disclosure is not limited to the disclosed embodiments, but instead is also capable of numerous rearrangements, modifications, and substitutions without departing from the present disclosure that as will be set forth and defined within the claims.

Further, please note that although the following description of some embodiments of the present disclosure is given in the context of electronic device/apparatus, the present disclosure is not limited thereto. In fact, as long as heat dissipation is involved, the inventive concept of the present disclosure may be applicable to any appropriate apparatus, etc.

Therefore, one skilled in the arts could readily understand that the terms used herein may also refer to their equivalents in any other infrastructure. For example, the term “User Equipment” or “UE” used herein may refer to a filter, a terminal device, a mobile terminal, a mobile station, a user device, a user terminal, a wireless device, a wireless terminal, or any other equivalents.

Further, the expression “Ais connected or coupled to or communicated to B” used herein may refer to that A may be coupled to B fluidly, mechanically, electrically, optically, electro-magnetically or in any other manner, either directly or indirectly, such that A can communicate with B or a fluid output from A may arrive at B, or vice versa.

Please note that although some embodiments will be described below in the context of one or more of the electronic device, the present disclosure is not limited thereto. In fact, the radiator according to some embodiments of the present disclosure may also be applicable to other apparatus than those described hereinafter.

There are generally two kinds of liquid cooling methods. One is active liquid cooling. The other is passive liquid cooling. The active liquid cooling device has dynamic part (pump) included which has the concern of low reliability and not power saving. The passive liquid cooling device has no dynamic part included which is high reliability. Network products always have high requirement on reliability. Thus, passive liquid cooling is a good selection.

The present disclosure proposes to introduce a passive cooling device, such as a radiator including a loop thermosyphon, into an electronic device, greatly enhancing cooling capacity and efficiency. Further, the electronic device is provided with a heat sink cover that can also dissipate heat in air cooling manner. That is, the electronic device can be cooled by means of a combination of the heat sink cover with the radiator, and thus has enhanced heat dissipation effect.

A radiator including a loop thermosyphon includes an evaporator and a condenser which couple with each other by a vapor pipe and a liquid pipe. The evaporator, the condenser, the vapor pipe and the liquid pipe form a closed loop space inside. The closed loop space is vacuumed and partly filled with a working fluid. The working fluid is vaporized in the evaporator when there is heat absorbing. The vaporized working fluid is converted back into liquid phase of the working fluid after releasing heat in condenser. It is the density difference between liquid working fluid and vapour working fluid that drives the working fluid circulation in loop thermosyphon. In a typical loop thermosyphon design, the liquid working fluid enters the evaporator on a side while the vapour working fluid is expelled from the evaporator on the opposite/adjacent side. And the vapour working fluid enters the condenser on a side while the liquid working fluid is expelled from the condenser on the opposite side.

The inventor realizes the advantages of the loop thermosyphon in terms of high cooling efficiency and proposes a new approach to apply the loop thermosyphon device, such as a radiator, in an electronic device, improving the cooling ability of the electronic device while maintaining reliability and compaction of thereof. Embodiments of an assembly for dissipating heat from an electronic device and the electronic device, including a radiator, are listed for illustrating the inventive concept as below.

FIGS. 1A and 1B are schematic diagrams illustrating an exemplary assembly for dissipating heat from an electronic device according to an embodiment of the present disclosure. As shown in FIGS. 1A and 1B, the assembly includes a top cover 10, a heat sink cover 20 and a bottom cover 40. The electronic device 30, such as a printed circuit board (PCB) , is enclosed by the assembly of the embodiment. In FIG. 1B, the electronic device 30 is sandwiched between the heat sink cover 20 and the bottom cover 40.

FIG. 2 schematically illustrates the assembly for dissipating heat from an electronic device as shown in FIG. 1A, but the top cover 10 is removed for exposing the heat sink cover 20, and furthermore, the assembly is shown in reversed manner relative to that in FIG. 1B. In FIG. 2, the bottom cover 40 is behind the paper and cannot be seen.

By reference with FIGS. 1A, 1B and 2, the assembly for dissipating heat from an electronic device according to the embodiment includes the heat sink cover 20, which has a first face (facing backwards of the paper in FIG. 2) and a second face (facing towards outside of the paper in FIG. 2) in opposite to the first face. The heat sink cover 20 may have a generally plate shape, and as shown, have a certain thickness. The heat sink cover 20 is configured to at least partly connect to, for example by a screw, and contact the electronic device by the first face so as to dissipate heat from the electronic device 30. The assembly may be provided with a radiator. At least part of the radiator is mounted on the second face of the heat sink cover 20. That is, in the embodiment, the heat sink cover 20 may be mounted or connected to the electronic device 30, and the radiator is not directly mounted on/connected to the electronic device 30, but is mounted on the heat sink cover 20. However, this is not tended to mean the radiator does not contact the electronic device 30. On the contrary, the radiator does contact the electronic device 30 by at least a part thereof. By this way, the radiator is isolated from the electronic device 30 by the heat sink cover 20. After mounting the top cover 10, the radiator is sandwiched between the top cover 10 and the heat sink cover 20.

According to the embodiment as shown in FIG. 2, the radiator may include at least one evaporator, such as two evaporators 220, 221, a condenser 300 and a connection part between the at least one evaporator and the condenser 300. The evaporator is configured to absorb heat from the electronic device 30 and evaporate a liquid working fluid to a gaseous working fluid therein. The condenser 300 is configured to condense the gaseous working fluid from the evaporator. The connection part between the evaporator and the condenser 300 may be a conduit, such as a pipe. The conduit may have a circular cross section, or a rectangle cross section or any other shaped cross section. The conduit may be flexible, and thus allow to be transformed so that the condenser and the evaporator may be located freely and easily relative to each other within the electronic device 30.

In an embodiment, the working fluid may be water, alcohol, carbinol, or any of other coolants which can be evaporated to gaseous phase and condensed to liquid phase. Those skilled in the art may select a suitable coolant according to design specification.

According to embodiment of the present disclosure, the heat sink cover 20 is provided with at least one window 121, 122 to expose at least part of the electronic device 30, such as at least one of power elements of the electronic device 30. The electronic device 30 may have a plurality of high-power elements and low-power elements, which each generate heat. The high-power element may generate more heat and here be denoted as a first heat source, and the low-power element may generate relative less heat and here be denoted as a second heat source. FIG. 6 shows a cross section view of an embodiment in which the high-power elements 132, 133 and the low-power element 135 are schematically illustrated. It is noted that there may be other high-power elements and/or low-power elements on the electronic device 30, and the shown elements in FIG. 6 are tended to limit neither the number of the power elements nor the proportion of the high-power elements to low-power elements. In the embodiment, the windows 121, 122 of the heat sink cover 20 expose the first heat sources 132, 133, i.e., the high-power elements here. As shown in FIG. 6, the two evaporators 220, 221 contact the first heat sources 132, 133 of the electronic device 30 respectively, through the respective one of the windows 121, 122 of the heat sink cover 20. In an embodiment, the assembly may be configured such that all the first heat sources 132, 133 of the electronic device 30 contact the evaporators 220, 221 respectively. However, in some embodiment, the assembly may be configured such that some of the first heat sources 132, 133 of the electronic device 30 contact the evaporator respectively, and the remainder ones of the first heat sources 132, 133 do not contact the evaporator. In another embodiment, the assembly may be configured such that the evaporator 220 or 221 may contact at least one second heat source 135 of the electronic device 30, through the window 121, or 122 of the heat sink cover 20. Those skilled in the art can freely configure the assembly so as to cool the heat source of the electronic device 30 by the radiator through the window as desired, based on the teachings of present disclosed embodiments.

In an embodiment, the assembly is configured to allow a part of the first face of the heat sink cover 20 to contact at least one second heat source 135 of the electronic device 30. That is, according to the embodiment, the evaporators 220, 221 at the second face, through the windows 121, 122 of the heat sink cover 20, contact the first heat sources 132, 133 of the electronic device 30 respectively, and at the same time, a part of the first face of the heat sink cover 20 contacts at least one second heat source 135 of the electronic device 30. By this way, generally all of or at least most of the high-power elements and the low-power elements, that is, such as the shown heat sources 132, 133, 135, of the electronic device 30 can be cooled efficiently as required. It is noted that the radiator is not limited by FIG. 2 to be only one, but in some embodiments, there may be two or more radiators.

According to the embodiment, due to provision of the windows 121, 122, configuration of the radiator on the heat sink cover 20 and furthermore the connection of the heat sink cover 20 to the electronic device 30, it allows at least the high-power element (s) 132, 133 of the electronic device 30 to be quickly cooled through the radiator, and at the same time, the heat sink cover 20 to dissipate heat of the low-power element 135 of the electronic device 30, thereby realizing a compact structure and sufficient heat dissipation of the electronic device 30, and furthermore achieving the advantages effect of easy installation and maintenance of the assembly. Further, according to the embodiment, due to the above configuration, the heat sink cover 20 may cover and seal the electronic device 30, and thus prevent migrant substances from damaging the electronic device 30, thereby improving reliability of the electronic device 30. In addition, the radiator may be assembled as a whole in advance and then be installed in the assembly, which strongly simplifies installation (particularly favorable in field) and improves service efficiency of the assembly and an electronic apparatus including the assembly. Comparing with existing design, in which the evaporator is located in housing of the electronic device 30 while the condenser is located outside the housing and connected to the evaporators in the housing by a pipe (s) , the assembly in present invention involves reduced leaky risk and simplified installation.

As described above, according to the embodiments of the present disclosure, when the evaporators 220, 221 of the radiator have been mounted on the windows 121, 122 of the second face of the heat sink cover 20 respectively, the face, facing to the heat sink cover 20, of the electronic device 30 may be sealed by the heat sink cover 20 and the evaporators 220, 221 of the radiator on the heat sink cover 20 as shown in FIG. 5.

In the embodiment as shown in FIG. 2 (b) , the radiator may have two or more evaporators 220, 221 and a condenser 300. FIG. 3 separately shows the radiator in operation state. The evaporators 220, 221 are communicated independently to the condenser 300 from each other. That is, each of the evaporators 220, 221 is directly connected to the condenser 300 by a pipe, and the evaporator 220 and the evaporator 221 are not directly connected to each other. This is advantageous that the evaporator 220 and the evaporator 221 can absorb heat from respective heat source without being affected by the other heat source. During operation of the electronic device 30, various power elements will have different working manners and thus generate heat in different period time and/or generates heat in different amount in the same period time. In this context, the evaporator 220 may absorb, such as, more heat from its respective power element than the evaporator 221, and the heated working fluid at higher temperature in the evaporator 220 will not enter the evaporator 221 before entering the condenser 300, but directly enter the condenser 300 and be cooled in the condenser 300. By this way, it avoids affecting the power element corresponding to the evaporator 221 by the heat of the heated working fluid from the evaporator 220. According to the embodiment, the assembly used for the electronic device 30 could enhance cooling efficiency, and further improve reliability and stability of the electronic device 30.

FIG. 2 (b) separately shows the radiator used in the assembly as shown in FIG. 2 (a) . The radiator in FIG. 2 (b) has been reversed relative to the pose of the radiator in FIG. 2 (a) and FIG. 3 for illustrating the part of the evaporator contacting the heat source of the electronic device 30. As illustrated in FIG. 2 (b) , each evaporator 220, 221 includes an evaporator main body 256, 257 defining a first evaporator cavity 250 and a protruded part 224, 225 protruding from the evaporator main body 256, 257 and having a flat surface 226, 227. The flat surface 226, 227 is configured to contact the heat source during operation. By this way, the heat generated by the heat source 132, 133, i.e., power element, may be absorbed by the flat surface 226, 227. The protruded part 224, 225 defines a second evaporator cavity 251 and the second evaporator cavity 251 is communicated to the first evaporator cavity 250.

In an embodiment, an interface material may be provided between the flat surface 226, 227 of the protruded part 224, 225 and the at least one of first heat sources 132, 133. The interface material may improve contact between the flat surface 226, 227 of the protruded part 224, 225 and the heat sources 132, 133.

Returned to the embodiment of FIGS. 2 (a) and 2 (b) , the evaporator 220 includes an evaporator flange 228 configured to be mounted on inner perimeter of the corresponding window 121 so that the window 121 is covered after installing the evaporator 220, and the evaporator 221 includes an evaporator flange 229 configured to be mounted on inner perimeter of the corresponding window 122 so that the window 122 is covered after installing the evaporator 221. FIG. 5 shows the assembly of FIG. 2 (a) after the radiator having been mounted on the heat sink cover 20.

In an embodiment, the assembly may include a gasket 125. The gasket 125 may be disposed between the evaporator 220 and the inner perimeter of the window 121, and between the evaporator 221 and the inner perimeter of the window 122. Provision of the gasket 125 is advantageous because the gasket 125 can fill the gap between the evaporator 220, 221 and the inner perimeter of the windows 121, 122, and thus the evaporator can press the inner perimeter of the windows 121, 122 via the gasket 125, thereby forming sealing between the evaporator flange of the evaporator and the inner perimeter of the corresponding window, and providing electro-magnetic interference shielding. According to the embodiment, when the evaporators 220, 221 are close to the electronic device 30 through the windows 121, 122, the protruded part 224, 225 will firstly contact the heat source before the evaporator flange contacts the inner perimeter of the window, and there may be gap between the evaporators 220, 221 and the inner perimeter of the windows 121, 122 after having placed the evaporators 220, 221 in place. In this situation, the gasket 125 is provided and the gap can be sealed by the gasket 125. Thus, the gasket 125 may allow the design freedom of the evaporators 220, 221 and the windows 121, 122. For example, the protruded part 224, 225 of a type of radiator is smaller than the windows 121, 122. A relative large gap occurs between the evaporators 220, 221 and the inner perimeter of the windows 121, 122. In this case, the gasket 125 can be used to fill and seal the large gap between the evaporators 220, 221 and the inner perimeter of the windows 121, 122 so that no electromagnetic wave can leak through the windows 121, 122. By use of the gasket 125, it does not need to redesign a radiator to fit the windows 121, 122. Thus, the gasket 125 is advantageous to improve design freedom and sealing of the electronic device 30. In some embodiment, the gasket 125 may be water proof in line with requirements of a product.

As shown in FIG. 2 (a) , the evaporators 220, 221 may each be mounted on the heat sink cover 20 by screws 280 through the evaporator flanges 228, 229. In the embodiment, the screws 280 are screwed in screw holes 124 of the heat sink cover 20, and a spring 281 is provided to surround the screw 280 and between the screw 280 and the evaporator flanges 228, 229. FIG. 5 shows an embodiment in which the radiator has been mounted on the heat sink cover 20 and the evaporators 220, 221 have been mounted through the windows 121, 122. The windows 121, 122 are sealed by the evaporators 220, 221 of the radiator. In this situation, the screws 280 are not screwed all in the screw holes respectively, and the spring are pressed by the screws and thus the springs each press the evaporator flanges 228, 229.

With this configuration, the screws 280 are screwed in the screw hole 124, and the evaporator flanges 228, 229 contact and press the gasket 125. Due to this configuration including the screw 280 and spring 281, the spring may press the evaporator flange towards the gasket 125 on the inner perimeter of the window while holding the flat surface 226, 227 pressing on the heat source. In an exemplar embodiment, an electronic device 30 having a power element in a large size protruding in a direction perpendicular to the electronic device plane, and thus after mounting the evaporator on the heat source, the gap between the inner perimeter of the windows 121, 122 and the evaporator flange 228, 229 is relatively large. In this case, it only needs to use a gasket 125 with an enlarged thickness to seal between the evaporator flanges and the windows, without re-designing the windows 121, 122 of the heat sink cover 20 and/or re-selecting a new type of radiator.

In addition, due to the elastic connection between the evaporator and the heat source by the above described screw and the spring that can provide pressure force, the interface material may be thin film of the interface material. Comparing with the traditional solution, in which thick thermal interface material such as thermal pad, and thermal putty was used, the thin film of the interface material has a reduced thermal resistance, and thus the thermal transmission through the interface material can be improved.

Referring to FIGS. 2 and 5, in the embodiment, after the radiator having been mounted on the heat sink plate, the evaporators 220 or 221 are respectively placed on respective windows 121, 122, and the condenser 300 is placed on an edge, i.e., a rear edge (in the paper plane) , of the heat sink plate. The heat sink plate is provided with a plurality of heat sink cover fins 120. As shown in FIG. 2 and FIG. 5, there is no heat sink cover fin 120 disposed at the locations where the condenser 300 and the windows 121, 122 are disposed. To some extent, the condenser 300 on the heat sink cover 20 is isolated from the electronic device 30 by the heat sink cover 20. This is advantageous that the condenser 300 will bring heat to the part, adjacent to the condenser 300, of the electronic device 30 as little as possible, avoiding affecting the elements on the electronic device 30.

In an embodiment, as shown in FIG. 5, the assembly may include a fan (or a fan set) configured adjacent to the heat sink cover 20 and the condenser 300 at a rear side (in the shown paper) , extending between the first face and the second face, of the heat sink cover 20. The fan is configured to draw air from a front side (in the shown paper) of the heat sink cover 20 via the heat sink cover fins 120 towards the condenser 300 in the rear side. In an embodiment, the fan is located at a level higher than the heat sink cover 20. In another embodiment, the fan may be disposed to face towards the electronic device.

In the embodiment as shown in FIG. 5, the heat sink cover fins 120 are arranged with a space between adjacent two of the heat sink cover fins 120. The space opens towards the fan, such that the drawn air passes through the space. FIG. 5 illustrates the heat sink cover fins 120 to be straight and parallel to each other. However, the heat sink cover fins 120 are not limited to be configured in the way as shown. In another embodiment, the heat sink cover fins 120 are arranged to define a wriggled channel between adjacent ones thereof.

With this configuration, the air is drawn by the fan to flow through the spaces among the heat sink cover fins 120 and thus transfers the heat away from the heat sink cover fins 120, and thus the temperature of the heat sink cover fins 120 can be reduced. Meanwhile, the air flows through the condenser 300 and dissipates the heat of the condenser 330, and decreases the temperature of the condenser 300.

In the embodiment as shown in FIG. 5, the condenser 300 is placed at the rear edge of the heat sink cover 20, where less heat sources are distributed and thus the generated heat is relatively less. This is advantageous because the part of the electronic device corresponding to the rear edge contains reduced elements, and thus generates less heat and does not need to be dissipated. Meanwhile, at the rear edge, the condenser 300 including a plurality of inner fins 311 in high density and thus having higher cooling efficiency can dissipate heat conveyed through the working fluid from the heat sources at the other locations of the electronic device 30, such as the area with high density power elements. By this way, the cooling efficiency of the assembly with the radiator including loop thermosyphon gets improved, and heat distribution over the electronic device 30 can become even to some extent.

The embodiments shown in FIGS. 2 and 5 is removed the top cover 10. The top cover 10 may be mounted on the heat sink cover 20. Referring to FIG. 1A, the top cover 10 may be connected to the heat sink cover 20 by a plurality of screws. The radiator is sandwiched between the top cover 10 and the heat sink cover 20. The connection of the top cover 10 with the heat sink cover 20 may allow air to flow through the space among the heat sink cover fins due to extension the heat sink cover fins in a direction perpendicular to the top cover 10 plane, while maintaining sealing of the electronic device 30. Actually, with this configuration, the space may be formed with the top cover 10 to a channel, in which air can be accelerated and thus heat dissipating efficiency can be increased.

In the embodiment as shown in FIG. 1B, the bottom cover 40 may be mounted on the electronic device 30, or on the heat sink cover 20. In the embodiment, the bottom cover 40 is configured so that there is an air flowing path between the bottom cover 40 and electronic device 30/the heat sink cover 20. By this way, the electronic device 30 is sandwiched between the bottom cover 40 and the heat sink cover 20, and air can flow through the air flowing path between the bottom cover 40 and the heat sink cover 20 to cool the back face of the electronic device 30. According to the embodiment as shown in FIG. 1A and 1B, the electronic device 30 thus can be cooled from both its faces, in which the front face is cooled by the heat sink cover 20 with the heat sink cover fins 120 and the radiator, and the back face is cooled by means of the air flowing path. Thus, the electronic device 30 can be efficiently cooled by the assembly according to the embodiments of the present disclosure.

In an embodiment, the assembly may include a fan tray 50, and the fan or a fan set is mounted in the fan tray 50. The fan tray 50 may be coupled to and abut against the first (rear) side of the heat sink cover 20. This is advantageous, because the air can be drawn from the second (front) side (relative to the paper) by means of the fan or fan set. As described above, on the second face of the heat sink cover 20, the air can be drawn by the fan (s) on the fan tray 50, from the front side into the spaces among the heat sink cover fins 120, towards the condenser 300 at the rear side. The heat sink cover fins 120 and the condenser 300 thus can dissipate their heat. Meanwhile, at the first face of the heat sink cover 20, the air can be drawn by the fan (s) or fan set on the fan tray 50, from the front side into the air flowing path, towards the second side, flowing over the back face of the electronic device 30. The back face of the electronic device 30 thus can be cooled. With this configuration, a single fan tray 50 can achieve cooling both faces of the electronic device 30, and at the same time the electronic device 30 can be maintained to be sealed by the heat sink cover 20 and the radiator from interference of foreign material drawn by the fan or fan set.

In an embodiment, the fan tray is configured to be flush with the top cover 10 and the bottom cover 40 in top and down direction. This is advantageous that the assembly including the fan tray may have a general integral housing and thus air may be drawn within the housing. Furthermore, the assembly looks more compact and is easy to be transported.

FIG. 3 shows a whole radiator separately. The radiator in FIG. 3 is shown in an operation state. The condenser 300 is located at a lever higher than the evaporators 220, 221. The evaporators 220 and 221 each may have a raised portion 254, 255 protruding from the evaporator main body 256, 257 and defining a third evaporator cavity 252. From FIG. 2, it can be seen that the raised portion 254, 255 is opposite to the protruded part 224, 225 with respect to the evaporator main body 256, 257. The third evaporator cavity 252 is communicated to the first evaporator cavity 250.

In the embodiment, referring to FIG. 7, FIG. 7 shows a cross section of the evaporator in an embodiment, with other component being removed. As shown in FIG. 7, the evaporator may include three sub-cavities, i.e., the first evaporator cavity 250 of the evaporator main body 256, 257, the second evaporator cavity 251 of the protruded part 224, 225 and the third evaporator cavity 252 of the raised portion 254, 255. In other words, the first evaporator cavity 250 together with the second evaporator cavity 251 and the third evaporator cavity 252 form a whole evaporator cavity. The raised portion includes an evaporator outlet 261 configured to output working fluid to the condenser 300, and the evaporator main body comprises an evaporator inlet 260 configured to intake the working fluid from the condenser 300.

According to the embodiments, the second evaporator cavity 251 is designed to contact the heat source and absorb heat from that, and the working fluid within the second evaporator cavity 251 will be heated directly and then rises to the first evaporator cavity 250 mixing with the working fluid therein. After sufficiently mixing and heat-exchanging, the working fluid at lower temperature drops, and the gaseous working fluid at higher temperature rises to the third evaporator cavity 252. To some extent, the third evaporator cavity 252 may function as collector for the gaseous working fluid as it is located at highest level. With this configuration, the working fluid may flow in convection current within the three sub-cavities so that the working fluid at lowest temperature can be collected in the second evaporator cavity 251 for absorbing heat, and the gaseous working fluid can be collected in the third evaporator cavity 252. Thus, the three-subcavity structure is advantageous as the pressure in the third evaporator cavity 252 will be more stable, and the working fluid outputted from the third evaporator cavity 252 of the evaporator may be fully in gaseous phase, which improves cooling capacity of the radiator.

It is noted that the third evaporator cavity 252 is not necessary for the present application, and an embodiment in which the raised portion 254, 255 and the evaporator main body 256, 257 have the same horizontal section can be considered as a two-cavity evaporator with increasing height.

FIG. 4 schematically shows an exploded isometric view of the condenser 300 of the radiator according to an embodiment. The condenser 300 comprises a condenser main body defining a first condenser cavity 314, and at least one dropped portion 317 defining a second condenser cavity 318 at a level lower than that of the first condenser cavity 314. The first condenser cavity 314 has a volume larger than that of the second condenser cavity 318 and communicating with the second condenser cavity 318 to constitute a whole condenser cavity. The condenser main body comprises condenser inlets 322, 323 configured to intake the working fluid from the evaporators 220, 221 respectively to the first condenser cavity 314, and the at least one dropped portion comprises at least one condenser outlet 321 configured to output the working fluid from the second condenser cavity 318 to the evaporator main body 256, 257 of the at least one evaporator, via the evaporator inlet 260.

The condenser main body 256, 257 comprises a base 240, and the inner fins 311 are provided on upper face of the base 240 in the first condenser cavity 314 of the condenser 300. The inner fins 311 are arranged in a polygonal shape, different from the rectangle of the base 240. At the corner of the base 240 in a shape of rectangle, no inner fin 311 is provided forming a margin region. The margin region is enclosed within the condenser 300. The margin region looks like a cut area of the polygonal shape of the arranged inner fins 311. In an embodiment, at least one side of the polygonal shape is oblique with respect to a direction in which the plurality of inner fins 311 are arranged. Due to the cut area, the working fluid in the first condenser cavity 314 can flow sufficiently and is easy circulated within the first condenser cavity 214, thereby achieving sufficient contact between the working fluid and the inner fins 311.

According to an embodiment, the inner fins 311 in the condenser 300 may be configured in higher density relative to the heat sink cover fins 120 on the heat sink cover 20. Due to the high-density inner fins 311, the condenser 300 can cool the working fluid in increased efficiency and thus the radiator can have higher cooling efficiency relative to the heat sink cover 20. Therefore, by adding the radiator onto the heat sink cover 20, the total heat dissipation efficiency of the assembly for the electronic device 30 will be significantly increased, although part of the heat sink cover fins may be removed for the sake of placing the radiator.

The condenser 300 may include external fins 330 outside the first condenser cavity and on lower face of the base 240. Referring to FIG. 3, the external fins 330 on the lower face of the base 240 may lift the condenser cavity to a raised level than the evaporator. In other words, the base 240 is higher than at least a bottom of the evaporator. Due to gravity, the heated working fluid in the evaporator rises, and leaves the evaporator into the condenser 300, and the liquid working fluid in the condenser 300 at lower temperature flows towards, actually downwards, the evaporator. By this way, the circulation of the working fluid may initiates. It is appreciated that here “upper” and “lower” , and the level are all described with respect to the operation state of the radiator.

FIG. 8 schematically shows a cross section of the condenser 300 of the radiator according to an embodiment, in which the external fins 330 are removed.

Referring to FIGS. 4 and 8, the base 240 includes an elongated through hole 316 configured to communicate the first condenser cavity 314 with the second condenser cavity 318. The through hole 316 in the base 240 and the second condenser cavity 318 may be formed as a whole cavity at a level below the first condenser cavity 314. It is noted that the elongated through hole 316 is shown in FIG. 8 to extend by about half of the width of the base 240 as an example. The elongated through hole 316, however, may have more or less length extending along the width of the base 240. The condenser outlet 321 is provided below the base 240, and the condenser inlet 322 is provided above the base 240.

In an embodiment not shown, the base 240 may has a recess, which provides the second condenser cavity 318, and does not have the dropped portion 317 as described above. The recess, i.e., the second condenser cavity 318 in the recess, is communicated to the first condenser cavity 314. It is appreciated that the second condenser cavity 318 may be considered as a part of the first condenser cavity 314, which is located at a dropped level in comparison with other part of the first condenser cavity 314. In the embodiment, the condenser outlet 321 may be disposed in the base 240. In an embodiment, the condenser outlet 321 is provided below the base 240, and thus is located among the external fins 330. The condenser 300 having the first condenser cavity 314 and the second condenser cavity 318 is advantageous that the condensed liquid working fluid can be accumulated in the second condenser cavity 318 so that the outputted liquid working fluid contains gaseous working fluid as less as possible, thereby improving the cooling efficiency. In addition, the mixture of the gaseous working fluid and liquid working fluid contains turbulence flow in the first condenser cavity 314. However, the liquid condensed liquid working fluid accumulated in the second condenser cavity 318 involves substantially no turbulence flow, and thus the outputted liquid working fluid will bring substantially no turbulence flow and thus the circulation of the working fluid may be improved and the radiator can be improved with enhanced reliability.

In order to describe a whole radiator, FIG. 3 illustrates a radiator used in an embodiment of the assembly. The radiator includes a condenser 300 and two evaporators 220 or 221, which has been described above. The evaporators 220 or 221 are not connected fluidly directly but independently connected to the common condenser 300 by conduit. In the embodiment, the conduit is shown as gaseous working fluid pipes 101, 102 and liquid working fluid pipes 411, 412. In FIG. 3, the conduit is shown as rectangle pipe, but it is not necessary to be the case. In another embodiment, the conduit may be circular pipe. During operation, the evaporator 220, 221 may evaporate to generate gaseous working fluid and output it through the gaseous working fluid pipes 101, 102 to the condenser 300, and the condenser 300 may condense the gaseous working fluid to liquid working fluid, and output it through the liquid working fluid pipes 411, 412 to the evaporator 220, 221 respectively.

The liquid working fluid pipes 411, 412 and the gaseous working fluid pipes 101, 102 may be made of suitable material to achieve fluid seal during conveying the working fluid. The liquid working fluid pipes 411, 412 and the gaseous working fluid pipes 101, 102 may be made by the same material or by different materials, as long as they can implement their own functions of conveying working fluid and maintaining pressure in the circulation loop thermosyphon. The liquid working fluid pipes 411, 412 and the gaseous working fluid pipes 101, 102 may be flexible so as to facilitate installation of the evaporators and the condenser of the radiator.

Here, it is described that the working fluid may be evaporated in the evaporator into gaseous working fluid. However, it is appreciated that, initially, the working fluid is liquid and may be not transformed into the gaseous working fluid even though it were heated. In this moment, the radiator also can work and dissipate heat for the electronic device 30. As the condenser 300 is located higher than the evaporator, due to gravity, the heated working fluid in the evaporator rises, and leaves the evaporator into the gaseous working fluid pipes, and the liquid working fluid in the condenser 300 at lower temperature flows towards, actually downwards, the evaporator. By this way, the circulation of the working fluid may initiates. When the power elements on the electronic device 30 continue to work and more heat generates, the working fluid in the evaporator may be heated into gaseous working fluid and loop thermosyphon actions.

Another aspect of the present disclosure provides an electronic apparatus. The electronic apparatus includes the assembly as described above. In the embodiment, the electronic apparatus may be a filter, a communication device, terminal device, a user device, a user terminal, a wireless device, a wireless terminal, a vehicle mounted devices, a computing power equipment, a computer, a processor, a radar or any other suitable device. The electronic apparatus may include at least one electronic device which contains a plurality of heat sources, such as power elements.

The disclosure has been described with reference to embodiments and drawings. It should be understood that various modifications, alternations and additions can be made by those skilled in the art without departing from the spirits and scope of the disclosure. Therefore, the scope of the disclosure is not limited to the above particular embodiments but only defined by the claims as attached and equivalents thereof.

Claims

An assembly for dissipating heat from an electronic device (30) , comprising

a heat sink cover (20) having a first face and a second face in opposite to the first face, the heat sink cover being configured to at least partly connect to and contact the electronic device on the first face so as to dissipate heat from the electronic device (30) , and

a radiator, at least part of the radiator being mounted on the second face of the heat sink cover (20) ;

wherein the radiator comprises:

at least one evaporator (220, 221) configured to absorb heat from the electronic device and evaporate a liquid working fluid to a gaseous working fluid therein;

a condenser (300) configured to condenser the gaseous working fluid from the at least one evaporator (220, 221) ; and

a connection part between the at least one evaporator (220, 221) and the condenser (300) ;

wherein the heat sink cover (20) is provided with at least one window (121, 122) to expose at least one of first heat sources (132, 133) of the electronic device (30) , and

the at least one evaporator (220, 221) contacts the at least one of the first heat sources (132, 133) of the electronic device (30) , through the at least one window (121, 122) of the heat sink cover (20) .
The assembly according to claim 1, wherein at least part of the first face of the heat sink cover (20) contacts at least one second heat source of the electronic device (30) .
The assembly according to claim 1, wherein the at least one evaporator (220, 221) includes two or more evaporators (220, 221) , and the two or more evaporators (220, 221) are communicated independently to the condenser (300) from each other.
The assembly according to claim 1, wherein the at least one evaporator (220, 221) each comprises an evaporator main body (256, 257) defining a first evaporator cavity (250) , and a protruded part (224, 225) protruding from the evaporator main body and having a flat surface (226, 227) , such that the flat surface (226, 227) contacts the at least one of the first heat sources during operation,

wherein the protruded part (224, 225) defines a second evaporator cavity (251) and the first evaporator cavity (250) is communicated to the second evaporator cavity (251) .
The assembly according to claim 1, wherein the at least one evaporator (220, 221) each comprises an evaporator flange (228, 229) configured to be mounted on inner perimeter of the at least one window (121, 122) so that the at least one window (121, 122) is covered after installing the at least one evaporator (220, 221) .
The assembly according to claim 5, wherein a gasket (125) is provided between the evaporator flange (228, 229) and the inner perimeter of the at least one window (121, 122) .
The assembly according to claim 5, wherein an interface material is provided between the flat surface (226, 227) of the protruded part (224, 225) and the at least one of first heat sources (132, 133) .
The assembly according to claim 6, wherein the evaporator flange (228, 229) is mounted on the heat sink cover (20) by a screw (280) and a spring (281) , wherein the screw is screwed in a screw hole (124) of the heat sink cover (20) , and the spring is provided to surround the screw and between the screw and screw hole (124) , so as to contact and press the flange towards the gasket (125) .
The assembly according to any one of the preceding claims, wherein the condenser (300) is isolated from the electronic device (30) by the heat sink cover (20) .
The assembly according to any one of the preceding claims, wherein the second face of the heat sink cover (20) is provided with heat sink cover fins (120) .
The assembly according to any one of the preceding claims, comprising a fan configured adjacent to the heat sink cover (20) and the condenser (300) at a first side, between the first face and the second face, of the heat sink cover, so as to draw air from a second side of the heat sink cover via the heat sink cover fins (120) of the heat sink cover (20) towards the condenser (300) , the second side being opposite to the first side.
The assembly according to claim 11, wherein the heat sink cover fins (120) are arranged so that a space between adjacent two of the heat sink cover fins (120) opens towards the fan, such that the drawn air passes through the space.
The assembly according to claim 4, wherein the at least one evaporator (220, 221) each comprises a raised portion (254, 255) protruding from the evaporator main body (256, 257) and defining a third evaporator cavity (252) , the raised portion being opposite to the protruded part (224, 225) with respect to the evaporator main body,

wherein the third evaporator cavity is communicated to the first evaporator cavity (250) , so that the first evaporator cavity (250) together with the third evaporator cavity (252) and the second evaporator cavity (251) form a whole evaporator cavity.
The assembly according to claim 13, wherein the raised portion comprises an evaporator outlet (261) configured to output working fluid to the condenser (300) ,

wherein the evaporator main body (256, 257) comprises an evaporator inlet (260) configured to intake the working fluid from the condenser (300) .
The assembly according to claim 14, wherein the condenser (300) comprises a condenser main body defining a first condenser cavity (314) , and at least one dropped portion (317) defining a second condenser cavity (318) at a level lower than that of the first condenser cavity (314) , the first condenser cavity (314) having a volume larger than that of the second condenser cavity (318) and communicating with the second condenser cavity (318) to constitute a whole condenser cavity.
The assembly according to claim 15, wherein the condenser main body comprises at least one condenser inlet (322) configured to intake the working fluid from the at least one evaporator (220, 221) respectively to the first condenser cavity (314) , and the at least one dropped portion comprises at least one condenser outlet (321) configured to output the working fluid from the second condenser cavity (318) to the evaporator main body of the at least one evaporator, via the evaporator inlet (260) .
The assembly according to claim 16, wherein the condenser main body comprises a base (228) , and internal fins (311) therein disposed on upper face of the base (228) ; and

the condenser (300) further comprises external fins (330) disposed on lower face of the base (228) , outside of the first condenser cavity (314) .
The assembly according to claim 17, wherein the base (228) comprises an elongated through hole (316) configured to communicate the first condenser cavity (314) with the second condenser cavity (318) .
The assembly according to claim 1, further comprising a top cover (10) configured to connect to the first face of the heat sink cover (20) and seal the electronic device therebetween.
The assembly according to claim 1, further comprising a bottom cover (40) configured to couple to the heat sink cover (20) , so that the bottom cover (40) and the heat sink cover (20) define an air flowing path between the bottom cover and the heat sink cover.
The assembly according to claim 11, further comprising a fan tray (50) coupled to and abutting against the first side of the heat sink cover (20) , wherein the fan is mounted in the fan tray (50) .
An electronic apparatus, comprising the assembly according to any one of claims 1-21.