THREE-DIMENSIONAL HEAT TRANSFER DEVICE

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of and claims priority under 35 U.S.C. § 120 to U.S. application Ser. No. 17/902,407 filed Sep. 2, 2022, which claims priority under 35 U.S.C. § 119(a) to Patent Application No(s). 202210011964.0 filed in China on Jan. 6, 2022. The entire contents of all these applications are hereby incorporated by reference.

BACKGROUND

The disclosure provides a heat transfer device, more particularly to a three-dimensional heat transfer device.

The technical principle of a vapor chamber is similar to a heat pipe, but there are differences between them in heat transfer. The heat pipe only transfers heat in one dimension, but the vapor chamber transfers heat in two dimensions and thus has better heat dissipation efficiency. Specifically, the vapor chamber mainly includes a chamber and a capillary structure. The chamber has an interior space for accommodating working fluid, and the capillary is disposed in the interior space. The chamber has a heat absorbing portion and a condensation portion. The working fluid absorbs heat in the heat absorbing portion and vaporizes so as to spread all over the interior space. The vaporized working fluid can be condensed into liquid form in the condensation portion and return to the heat absorbing portion via the capillary structure so as to complete a cooling cycle.

However, the vapor chamber and the heat pipe work independently, and therefore only one dimensional and/or two dimensional heat transfer may be satisfied, which is unable to achieve three dimensional heat transfer.

SUMMARY

The disclosure provides a three-dimensional heat transfer device which can dissipate heat more efficiently.

One embodiment of the disclosure provides a three-dimensional heat transfer device. The three-dimensional heat transfer device includes a first thermally conductive casing, a second thermally conductive casing, at least one first capillary structure, at least one second capillary structure and at least one first heat pipe. The first thermally conductive casing has an outer surface, and the outer surface is configured to be in thermal contact with a heat source. The second thermally conductive casing has at least one first through hole. The second thermally conductive casing is attached to the first thermally conductive casing, and the first thermally conductive casing and the second thermally conductive casing together form a liquid-tight chamber. The first capillary structure is disposed on the first thermally conductive casing. The second capillary structure is disposed on the first thermally conductive casing. A projection of the first capillary structure and a projection of the second capillary structure on the outer surface and an extension surface of the outer surface are located in an extent of the outer surface, and the second capillary structure is located closer to the second thermally conductive casing than the second capillary structure. The first heat pipe is disposed through the first through hole and in contact with the second capillary structure. The annular outer wall and an annular inner wall of the first heat pipe together define a fourth capillary structure. The fourth capillary structure extends from a closed end to an open end in the first heat pipe. The open end of the first heat pipe is annular in shape with a central hole.

Another embodiment of the disclosure provides a three-dimensional heat transfer device. The three-dimensional heat transfer device includes a first thermally conductive casing, a second thermally conductive casing, at least one thermally conductive protrusion, at least one first capillary structure, at least one second capillary structure and at least one first heat pipe. The second thermally conductive casing has at least one first through hole. The second thermally conductive casing is attached to the first thermally conductive casing, and the first thermally conductive casing and the second thermally conductive casing together form a liquid-tight chamber. The thermally conductive protrusion protrudes from the first thermally conductive casing. The first capillary structure is stacked on the first thermally conductive casing. The second capillary structure is stacked on the thermally conductive protrusion and thermally coupled with the first capillary structure. The first heat pipe is disposed through the first through hole and in contact with the second capillary structure. The annular outer wall and an annular inner wall of the first heat pipe together define a fourth capillary structure. The fourth capillary structure extends from a closed end to an open end in the first heat pipe. The open end of the first heat pipe is annular in shape with a central hole.

According to the three-dimensional heat transfer device as discussed in the above embodiment, the first heat pipes are in contact with the second capillary structures located closer to the second thermally conductive casing, such that the areas of the capillary structures can be increased, and the backwater distances of the first heat pipes can be reduced so as to improve the heat dissipation efficiency of the three-dimensional heat transfer device.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become better understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only and thus are not intending to limit the present disclosure and wherein:

FIG. 1 is a perspective view of a three-dimensional heat transfer device according to one embodiment of the present disclosure.

FIG. 2 is an exploded view of the three-dimensional heat transfer device in FIG. 1.

FIG. 3 is another exploded view of the three-dimensional heat transfer device in FIG. 1.

FIG. 4 is a cross-sectional view of the three-dimensional heat transfer device in FIG. 1.

FIG. 5 is an exploded view of the three-dimensional heat transfer device in FIG. 1 according to one embodiment of the present disclosure.

FIG. 6 is an exploded view of the three-dimensional heat transfer device according to one embodiment of the present disclosure.

FIG. 7 is a cross-sectional view of the three-dimensional heat transfer device according to one embodiment of the present disclosure.

FIG. 8 is a perspective view illustrating a portion of the chamber S in detail according to one embodiment of the present disclosure.

FIG. 9 is a perspective view illustrating a portion of the chamber S in detail according to one embodiment of the present disclosure.

FIG. 10 is a perspective view illustrating a portion of the chamber S in detail according to one embodiment of the present disclosure.

FIG. 11 is a perspective view illustrating a portion of the chamber S in detail according to one embodiment of the present disclosure.

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.

In addition, the terms used in the present disclosure, such as technical and scientific terms, have its own meanings and can be comprehended by those skilled in the art, unless the terms are additionally defined in the present disclosure. That is, the terms used in the following paragraphs should be read on the meaning commonly used in the related fields and will not be overly explained, unless the terms have a specific meaning in the present disclosure.

Refer to FIGS. 1 to 4, where FIG. 1 is a perspective view of a three-dimensional heat transfer device 10 according to one embodiment of the disclosure, FIG. 2 is an exploded view of the three-dimensional heat transfer device 10 in FIG. 1, FIG. 3 is another exploded view of the three-dimensional heat transfer device 10 in FIG. 1, and FIG. 4 is a cross-sectional view of the three-dimensional heat transfer device 10 in FIG. 1.

In this embodiment, the three-dimensional heat transfer device 10 includes a first thermally conductive casing 100, a second thermally conductive casing 200, a plurality of thermally conductive protrusions 300, a first capillary structure 400, a plurality of second capillary structures 500, a plurality of third capillary structures 550, a plurality of first heat pipes 600 and a plurality of second heat pipes 700.

The first thermally conductive casing 100 and the second thermally conductive casing 200 are, for example, made of metal material via, for example, a sheet metal stamping process. The second thermally conductive casing 200 is attached to the first thermally conductive casing 100, and the first thermally conductive casing 100 and the second thermally conductive casing 200 together form a liquid-tight chamber S.

The first thermally conductive casing 100 includes a bottom plate 110, an annular side plate 120, a first protrusion structure 130 and a second protrusion structure 140. The annular side plate 120 is connected to a periphery of the bottom plate 110. The first protrusion structure 130 protrudes from the bottom plate 110 along a direction away from the second thermally conductive casing 200. The second protrusion structure 140 protrudes from the first protrusion structure 130 along a direction away from the second thermally conductive casing 200. The second protrusion structure 140 has an inner surface 141 and an outer surface 142 facing away from the inner surface 141. The outer surface 142 is configured to be in thermal contact with a heat source (not shown), such as a CPU or a GPU. The second thermally conductive casing 200 has a plurality of first through holes 210 and a plurality of second through holes 220.

The thermally conductive protrusions 300 are, for example, made of metal material. The thermally conductive protrusions 300 protrude from the inner surface 141 of the second protrusion structure 140 of the first thermally conductive casing 100. In addition, each of the thermally conductive protrusions 300 has a first surface 310 and a second surface 320, where the first surface 310 faces away from the outer surface 142 of the second protrusion structure 140, and the second surface 320 is located between and connected to the first surface 310 and the inner surface 141 of the second protrusion structure 140.

In this embodiment, the thermally conductive protrusions 300 are, for example, rectangular bodies with different lengths, but the disclosure is not limited thereto; in some other embodiments, the thermally conductive protrusion may be non-rectangular bodies as long as a desired vapor pressure drop in the liquid-tight chamber S can be provided, and a high liquid pressure drop caused by the sintered powder capillary structure can be reduced.

In this embodiment, the thermally conductive protrusions 300 are parallel with one another, but the disclosure is not limited thereto; in some other embodiments, the thermally conductive protrusions may be in a radial arrangement.

The first capillary structure 400 and the second capillary structures 500 may be selected from a group consisting of metal net, sintered powder and sintered ceramic. The first capillary structure 400 is stacked on at least part of inner surface 141 of the second protrusion structure 140 of the first thermally conductive casing 100. The second capillary structures 500 are respectively stacked on the first surfaces 310 of the thermally conductive protrusions 300. The third capillary structures 550 are respectively stacked on the second surfaces 320 of the thermally conductive protrusions 300 and connected to the first capillary structure 400 and the second capillary structures 500.

In this embodiment, a projection of the first capillary structure 400 and projections of the second capillary structures 500 on the outer surface 142 and an extension surface of the outer surface 142 are located in an extent of the outer surface 142; that is, the projection of the first capillary structure 400 and the projections of the second capillary structures 500 on the outer surface 142 and the extension surface of the outer surface 142 are located in an area defined by a contour C of the outer surface 142. The second capillary structures 500 are located closer to the second thermally conductive casing 200 than the first capillary structure 400 on the second protrusion structure 140 by disposing the second capillary structures 500 on the first surfaces 310 of the thermally conductive protrusions 300 instead of increasing the thicknesses of the second capillary structures, such that the second capillary structures 500 can have small thickness for reducing thermal resistances. That is, the thicknesses of the second capillary structures 500 can be reduced for achieving small thermal resistances by using the thermally conductive protrusions 300 to elevate the second capillary structures 500. When the thicknesses of the second capillary structures 500 are decreased from 0.6 mm to 0.4 mm, the thermal resistances thereof are decreased from 0.0333° C./W to 0.0222° C./W.

In this embodiment, each of the second capillary structures 500 has a top surface 510 facing away from the second protrusion structure 140, where top surface 510 is spaced apart from the inner surface 141 of the second protrusion structure 140 by a first distance D1. A vapor channel is formed between the inner surface 141 of the second protrusion structure 140 and the second thermally conductive casing 200, and the inner surface 141 of the second protrusion structure 140 is spaced apart from the second thermally conductive casing 200 by a second distance D2.

The first heat pipes 600 and the second heat pipes 700 can be distinguished by the positions where they are disposed. Projections of the first heat pipes 600 on the outer surface 142 of the second protrusion structure 140 and an extension surface of the outer surface 142 are located in the extent of the outer surface 142, which means that the projections of the first heat pipes 600 are located in the area defined by the contour C of the outer surface 142. Projections of the second heat pipes 700 on the outer surface 142 of the second protrusion structure 140 and the extension surface of the outer surface 142 are located outside the outer surface 142, which means that the projections of the second heat pipes 700 are located outside the area defined by the contour C of the outer surface 142.

The first heat pipes 600 are respectively disposed through the first through holes 210, and the first heat pipes 600 are respectively in contact with the second capillary structures 500 stacked on the first surfaces 310 of the thermally conductive protrusions 300, such that the first heat pipes 600 are spaced apart from the first capillary structure 400 stacked on the inner surface 141 of the second protrusion structure 140.

In addition, each of the first heat pipes 600 has a first chamber 610 and an opening 620, where the first chamber 610 is in fluid communication with the liquid-tight chamber S via the opening 620. The opening 620 is configured for working fluid (e.g., vapor) to pass therethrough.

In this embodiment, the first chamber 610 is in fluid communication with the liquid-tight chamber S via the opening 620, but the second capillary structure 500 may still expose a part of the first chamber 610 when the first heat pipe 600 is in contact with the second capillary structure 500. Therefore, in some other embodiments, the first heat pipe may not have the opening 620. In other words, in some other embodiments, the first chamber may be in fluid communication with the liquid-tight chamber via a gap that is not blocked by the second capillary structure.

In this embodiment, capillary structures (not shown) of the first heat pipes 600 are respectively connected to the second capillary structures 500 via metallic bonding manner, which means that capillary structures (not shown) of the first heat pipes 600 are respectively connected to the second capillary structures 500 via sintering process. By doing so, two capillary structures connected to each other can transmit the working fluid more rapidly so as to increase the heat dissipation efficiency of the three-dimensional heat transfer device 10. However, the disclosure is not limited thereto; in some other embodiments, the capillary structures of the first heat pipes may be merely in contact with the second capillary structures.

The second heat pipes 700 are respectively disposed through the second through holes 220, and the second heat pipes 700 are spaced apart from the first capillary structure 400. In addition, each of the second heat pipes 700, for example, has a closed second chamber 710 not in fluid communication with the liquid-tight chamber S.

Each of the support structures 800 has one end connected to the first thermally conductive casing 100 and another end connected to the second thermally conductive casing 200 so as to increase the structural strength of the three-dimensional heat transfer device 10. In this embodiment, the support structures 800 and the thermally conductive protrusions 300 may be integrally formed with the first thermally conductive casing 100 by stamping process, CNC process or another suitable process. In some other embodiments, the support structures and the thermally conductive protrusions may be coupled with the first thermally conductive casing via welding process, diffusion bonding process, thermal pressing process, soldering process, brazing process or adhering process.

In this embodiment, the thermally conductive protrusions 300 are connected to at least some of the support structures 800, but the disclosure is not limited thereto; in some other embodiments, the thermally conductive protrusions 300 may be spaced apart from the support structures 800.

Note that the quantities of the thermally conductive protrusions 300, the second capillary structures 500, the first heat pipes 600, and the second heat pipes 700 are not restricted in the disclosure. In some other embodiments, the quantities of the thermally conductive protrusion, the second capillary structure, the first heat pipe, and the second heat pipe may all be one.

In this embodiment, the three-dimensional heat transfer device 10 includes the first heat pipes 600 and the second heat pipes 700, but the disclosure is not limited thereto; in some other embodiments, the three-dimensional heat transfer device may not include any second heat pipe.

In this embodiment, the first heat pipes 600 are in contact with the second capillary structures 500 stacked on the first surfaces 310 of the thermally conductive protrusions 300 instead of on the first capillary structures 400 stacked on the second protrusion structure 140 of the first thermally conductive casing 100, such that there is no need to form structures on the thermally conductive protrusions 300 for the penetrations of the first heat pipes 600; that is, the volumes of the thermally conductive protrusions 300 can be increased so as to increase areas of the second capillary structures 500. In addition, by doing so, a backwater distance of each first heat pipe 600 can be reduced from L2 to L1 so as to improve the heat dissipation efficiency of the three-dimensional heat transfer device 10.

According to the three-dimensional heat transfer device as discussed in the above embodiment, the first heat pipes are in contact with the second capillary structures located closer to the second thermally conductive casing, such that the areas of the capillary structures can be increased, and the backwater distances of the first heat pipes can be reduced so as to improve the heat dissipation efficiency of the three-dimensional heat transfer device.

In addition, compare with two capillary structures merely in contact with each other, two capillary structures connected to each other via metallic bonding manner can transmit the working fluid more rapidly so as to increase the heat dissipation efficiency of the three-dimensional heat transfer device.

CIP Application

Refer to FIGS. 5 to 7. FIG. 5 is an exploded view of the three-dimensional heat transfer device 10A in FIG. 1, according to one embodiment of the present invention. FIG. 6 is another exploded view of the three-dimensional heat transfer device 10A in FIG. 1. FIG. 7 is a cross-sectional view of the three-dimensional heat transfer device 10A in FIG. 1. The three-dimensional heat transfer device 10A of this embodiment is similar to the heat pipe assembly 10, so the differences will be described, and the similarities will not be repeated.

In FIG. 5, each of the first heat pipes 600 includes a first chamber 610, a closed end 601 and an open end 630. The open end 630 is located at the opposite end of the first heat pipes 600 from the closed end 601. In one embodiment, the heat pipe has an open end 630 that is annular in shape, including a central hole at the open end 630. This design ensures an efficient and uniform distribution of thermal energy across the first heat pipe 600, optimizing the overall performance in thermal transfer applications. The annular configuration of the open end 630 provides several advantages, including enhanced surface area for thermal exchange and minimized resistance to the movement of working fluids within the heat pipe. The open end 630 inserts into the liquid-tight chamber S and is disposed on the second capillary structure 500 that is stacked on the first surface 310 of the thermally conductive protrusions 300. Because the open end 630 is spaced apart from the first capillary structure 400 that is stacked on the inner surface of the first thermally conductive casing 100, the first heat pipe 600 is in fluid communication with the liquid-tight chamber S.

Each of the first heat pipes 600 has an outer wall 602 and an inner wall (not shown) disposed within the first chamber 610, the inner wall facing away from the outer wall 602. A fourth capillary structure (not shown) that is disposed on the inner wall of the first heat pipe and is in contact with the second capillary, facilitating the movement of working fluid within the heat pipe. The annular design of the open end 630 improves the heat transfer efficiency of the heat pipe 600 by providing a consistent and evenly distributed opening, which can benefit applications requiring precise thermal management.

In FIG. 6, each of the first heat pipes 600 is inserted into the liquid-tight chamber S through the corresponding first through holes 210. These first through holes 210 are precisely aligned for the heat pipes 630, allowing for minimal thermal resistance at the points of insertion. The open end 630 of the first heat pipes 600 is inserted into the liquid-tight chamber S, so that the heat pipe 600 is in direct fluid communication with the liquid-tight chamber S.

In FIG. 7, each of the first heat pipes 600 are respectively in contact with the second capillary structures 500 that are stacked on the first surfaces 310 of the thermally conductive protrusions 300. Accordingly, the first heat pipes 600 are thermally coupled to the second capillary structure 500 and are spaced apart from the first capillary structure 400 that is stacked on the inner surface 141 of the second protrusion structure 140. Due to the spaces between the open end 630 of the first heat pipe 600 and the first capillary structures 400, the first chamber 610 of the first heat pipe 600 is in fluid communication with the liquid-tight chamber S via the central hole of the open end 630 of the first heat pipe 600. The central hole of the open end 630 is configured for working fluid to pass through.

In one embodiment, at least one of the thermally conductive protrusions 300 can be constructed using a non-solid mental, allowing for enhanced versatility in its material properties and performance. The non-solid metal may include materials such as sintered metals or porous structures that promote better thermal management through increased surface area and controlled porosity. These characteristics can contribute to more efficient heat dissipation and distribution within the system. According to one embodiment, at least one of the thermally conductive protrusions 300 can be integrated with at least one of the second capillary structures 500 and at least one of the third capillary structures 550. This integration forms a unified capillary structure that not only enhances thermal conductivity but also improves the capillary action necessary for optimal fluid movement. The unified capillary structure can be configured in a way that maximizes the wicking ability of the system, ensuring that the working fluid is distributed effectively throughout the heat pipes.

In one embodiment, at least one of the thermally conductive protrusions 300 can be designed as spaced segments or other forms of separated arrangements, where gaps or breaks are intentionally incorporated into the thermally conductive protrusions 300, providing a structural flexibility. These spaced segments create regions that allow for more effective heat dissipation by increasing surface area and enhancing airflow around the protrusions. This configuration also reduces thermal stress concentrations, thereby improving the overall durability and longevity of the system.

In one embodiment, the thermally conductive protrusions 300 are designed in a square shape, with each thermally conductive protrusion 300 spaced apart and arranged in a cross-like pattern, as shown in FIG. 8. This cross-like arrangement allows for heat transfer in multiple directions and creates a balanced structure for distributing thermal energy throughout the system. The square-shaped protrusions 300, with their defined edges and symmetrical layout, create a configuration that ensures equal heat distribution and effective cooling across the entire thermal interface. Further, the first heat pipes 600 are in contact with the second capillary structures (not shown) on the thermally conductive protrusion 300 and are in fluid communication with the light-tight chamber S.

In one embodiment, the thermally conductive protrusions 300 are rectangular-shaped and are spaced apart and arranged parallel to each other in a staggered pattern, as shown in FIG. 9. This staggered pattern promotes efficient linear heat transfer and reduces the thermal interference between adjacent thermally conductive protrusions 300. The rectangular shape is suitable for applications where controlling the direction of heat flow is prioritized, such as in devices requiring specific heat pathways along particular axes. Further, the first heat pipes 600 are in contact with the second capillary structures (not shown) on the thermally conductive protrusion 300 and are in fluid communication with the light-tight chamber S.

In one embodiment, the thermally conductive protrusions 300 are rectangular-shaped and are spaced apart and arranged in a cross-like pattern, as shown in FIG. 10. This cross-like arrangement allows for heat transfer in multiple directions and ensure that the thermal energy is evenly distributed across the entire structure. The cross-like pattern minimizes localized partially dry burning and increases the uniformity of cooling throughout the thermal interface. Further, the first heat pipes 600 are in contact with the second capillary structures (not shown) on the thermally conductive protrusion 300 and are in fluid communication with the light-tight chamber S.

In one embodiment, the thermally conductive protrusions 300 are triangular-shaped and extend radially outward from a central portion of the first thermally conductive casing 100, as shown in FIG. 11. This radial arrangement, with triangular-shaped thermally conductive protrusions 300, creates a spoke-like configuration that enhances radial heat dissipation. This arrangement is particularly effective in systems where centralized heat generation occurs, as it facilitates rapid dissipation of heat from the core to the outer edges of the casing. Further, the first heat pipes 600 are in contact with the second capillary structures (not shown) on the thermally conductive protrusion 300 and are in fluid communication with the light-tight chamber S.

Therefore, embodiments disclosed herein are well adapted to attain the ends and advantages mentioned as well as those that are inherent therein. The particular embodiments disclosed above are illustrative only, as the embodiments disclosed may be modified and practiced in different but equivalent manners apparent to those of ordinary skill in the relevant art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular illustrative embodiments disclosed above may be altered, combined, or modified and all such variations are considered within the scope and spirit of the present disclosure. Of course, the disclosed embodiments are merely exemplary embodiments and that various modifications can be made without departing from the spirit and scope of the disclosure. Further, it should be understood that various aspects of the embodiment are not mutually exclusive of each other and can be combined as desired by a person of ordinary skill in the art as a matter of design choices.

The embodiments illustratively disclosed herein suitably may be practiced in the absence of any element that is not specifically disclosed herein and/or any optional element disclosed herein. While compositions and methods are described in terms of “comprising,” “containing,” or “including” various components or steps, the compositions and methods can also “consist essentially of” or “consist of” the various components and steps. All numbers and ranges disclosed above may vary by some number. Whenever a numerical range with a lower limit and an upper limit is disclosed, any number and any included range falling within the range is specifically disclosed. In particular, every range of values (of the form, “from about a to about b,” or, equivalently, “from approximately a to b,” or, equivalently, “from approximately a-b”) disclosed herein is to be understood to set forth every number and range encompassed within the broader range of values. Also, the terms in the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the patentee. Moreover, the indefinite articles “a” or “an,” as used in the claims, are defined herein to mean one or more than one of the elements that it introduces.