LOOP THERMOSIPHON 3D VAPOR CHAMBER

Abstract

A 3D vapor chamber includes a lower body defining an evaporator region, a header positioned above the lower body, conduits extending between the lower body and the header, a condenser region, and a working fluid located within at least one of the lower body, the header, or the conduits. The conduits are configured to direct a flow of the working fluid to and from the lower body and the header. A portion of the working fluid is configured to be in vaporized form during use, and another portion of the working fluid is configured to be in liquid form during use. The conduits are arranged such that the vaporized working fluid and the liquid working fluid are configured to flow in a same direction in at least one of the conduits.

Description

FIELD

The present disclosure generally relates to thermal devices, including vapor chambers, for directing heat away from a heat source.

BACKGROUND

Thermal devices are commonly used to remove heat from a heat source. Thermal devices may be made at least partially, for example, of a thermally conductive material, and may contain a phase-change working fluid within the thermal device. The phase changes of the working fluid are used to dissipate heat from the heat source. Thermal devices commonly include an evaporator region that is in thermal communication with the heat source to receive heat from the heat source and to direct the heat to the working fluid, and a condenser region in thermal communication with the evaporator region, where the heat is dissipated from the working fluid to the external environment. Some thermal devices include a wick material disposed within the thermal device to generate a capillary action to facilitate return of the working fluid to the evaporator region.

During use, working fluid typically absorbs heat generated by and transferred from the heat source. The absorbed heat from the heat source vaporizes the working fluid (i.e., changes the phase of the working fluid), thereby transferring the heat away from the heat source. The heated vapor then flows to the cooler condenser region of the thermal device, where the vaporized working fluid condenses and changes phase again back to its liquid state.

Condensation of the vaporized working fluid dissipates the absorbed heat. The heat exits the condenser region, and enters the external environment. The cooled working fluid returns to the evaporator region, sometimes facilitated by capillary action provided by the wick structure. Once returned to the evaporator region of the thermal device, the working fluid again absorbs heat from the heat source. This heat dissipation cycle can be continuously repeated as long as the heat source generates heat.

SUMMARY

In accordance with one example, a 3D vapor chamber includes a lower body defining an evaporator region, a header positioned above the lower body, conduits extending between the lower body and the header, a condenser region, and a working fluid located within at least one of the lower body, the header, or the conduits. The conduits are configured to direct a flow of the working fluid to and from the lower body and the header. A portion of the working fluid is configured to be in vaporized form during use, and another portion of the working fluid is configured to be in liquid form during use. The conduits are arranged such that the vaporized working fluid and the liquid working fluid are configured to flow in a same direction in none, some, a majority, or all of the conduits.

In accordance with another example, a 3D vapor chamber includes a lower body defining an evaporator region, a header positioned above the lower body, conduits extending between the lower body and the header, a condenser region positioned between the lower body and the header, and a working fluid located within at least one of the lower body, the header, or the conduits. The 3D vapor chamber also includes a wick structure located within the lower body. The wick structure is positioned in the lower body so as to block movement of a vaporized portion of the working fluid, and to force the vaporized portion of the working fluid to enter one or more of the conduits, and to flow up into the upper header before flowing back down through one or more of the conduits.

In accordance with another example, a 3D vapor chamber includes a lower body defining a recessed well. The recessed well defines an evaporator region. The 3D vapor chamber also includes a header positioned above the lower body, conduits extending between the lower body and the header, a condenser region positioned between the lower body and the header, and a working fluid located within at least one of the lower body, the header, or the conduits. The 3D vapor chamber also includes a boundary wall located within the lower body. The boundary wall is configured to hold back a portion of the working fluid from entering the recessed well.

In accordance with another example, a 3D vapor chamber includes a lower body defining an evaporator region, a header positioned above the lower body, and conduits extending between the lower body and the header. The conduits are configured to direct a flow of working fluid between the lower body and the header. The 3D vapor chamber also includes a condenser region positioned between the lower body and the header. The conduits include a first conduit having a first width, and a second conduit having a second width different than the first width.

In accordance with another example, a 3D vapor chamber includes a lower body defining an evaporator region, a header positioned above the lower body, and conduits extending between the lower body and the header. The conduits are configured to direct a flow of working fluid between the lower body and the header. The 3D vapor chamber also includes a condenser region positioned between the lower body and the header. The conduits are sized and shaped such that a different aggregate cross-sectional area of the conduits exists for a vapor flow of the working fluid moving upwardly than for a return vapor flow of the working fluid moving downwardly.

In accordance with another example, a 3D vapor chamber includes a lower body defining an evaporator region, a header positioned above the lower body, and conduits extending between the lower body and the header. The conduits are configured to direct a flow of working fluid between the lower body and the header. The 3D vapor chamber also includes a condenser region positioned between the lower body and the header. The condenser region includes air-cooled fins arranged in stacks. A density of the air-cooled fins within one of the stacks varies within the stack.

In accordance with another example, a 3D vapor chamber includes a lower body defining an evaporator region, a header positioned above the lower body, and conduits extending between the lower body and the header. The conduits are configured to direct a flow of working fluid between the lower body and the header. The 3D vapor chamber also includes a condenser region positioned between the lower body and the header, and a wick structure located within the lower body. One or more of the conduits is in direct contact with the wick structure.

In accordance with another example, a 3D vapor chamber includes a lower body defining an evaporator region, a header positioned above the lower body, a condenser region positioned between the lower body and the header, and posts in the header. Each of the posts has a streamlined cross-sectional shape.

In accordance with another example, a 3D vapor chamber includes a lower body defining an evaporator region, a header positioned above the lower body, and conduits extending between the lower body and the header. The conduits are configured to direct a flow of working fluid between the lower body and the header. The 3D vapor chamber also includes a condenser region positioned between the lower body and the header. The condenser region includes air-cooled fins arranged in stacks. A density of the air-cooled fins in one stack is different than a density of air-cooled fins in a different stack.

In accordance with another example, a 3D vapor chamber includes a lower body defining an evaporator region, a header positioned above the lower body, and conduits extending between the lower body and the header. The conduits are configured to direct a flow of working fluid between the lower body and the header. The 3D vapor chamber also includes a condenser region positioned between the lower body and the header, and a wick structure that extends at least partially within one or more of the conduits or the header.

In accordance with another example, a 3D vapor chamber includes a lower body defining an evaporator region, a header positioned above the lower body, and conduits extending between the lower body and the header. The conduits are configured to direct a flow of working fluid between the lower body and the header. The 3D vapor chamber also includes a condenser region positioned between the lower body and the header. The evaporator region includes a lower wall, and fins that extend upwardly from the lower wall. The evaporator region further includes a wick structure that extends at least partially over the fins.

In accordance with another example, a 3D vapor chamber includes a lower body defining an evaporator region, a header positioned above the lower body, and conduits extending between the lower body and the header. The conduits are configured to direct a flow of working fluid between the lower body and the header. The 3D vapor chamber also includes a condenser region positioned between the lower body and the header. The evaporator region includes a parallel arrangement, grid, and/or any other regular or irregular pattern of fins, posts, and pockets.

In accordance with another example, a 3D vapor chamber includes a lower body defining an evaporator region, a conduit extending away from the lower body and looping back to the lower body, and a working fluid located within at least one of the lower body or the conduit. The conduit is configured to direct a flow of the working fluid to and from the lower body. A portion of the working fluid is configured to be in vaporized form during use, and another portion of the working fluid is configured to be in liquid form during use.

In accordance with another example, a thermal device includes an evaporator region having a plurality of extended surfaces that define a matrix, wherein the extended surfaces are configured to provide structural support for the evaporator region. The thermal device also includes a wick structure that covers at least a portion of the extended surfaces. The wick structure includes powder ribs.

In accordance with another example, a thermal device includes an evaporator region, a liquid reservoir located adjacent the evaporator region, and a screen positioned in the liquid reservoir.

The details of one or more aspects of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the techniques described in this disclosure will be apparent from the description and drawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic, cross-sectional view of a heat pipe in accordance with one example.

FIG. 2 is a schematic, cross-sectional view of a 2D vapor chamber in accordance with one example.

FIG. 3 is a schematic, cross-sectional view of a vapor chamber with heat pipe in accordance with one example.

FIG. 4 is a schematic, cross-sectional view of a round tube 3D vapor chamber in accordance with one example.

FIG. 5 is a schematic, cross-sectional view of a loop thermosiphon 3D vapor chamber in accordance with one example.

FIG. 6 is a schematic, cross-sectional view of a loop thermosiphon 3D vapor chamber in accordance with another example.

FIG. 7 is a schematic, cross-sectional view of a flow of working fluid through a loop thermosiphon 3D vapor chamber, in accordance with one example.

FIG. 8 is a perspective view of a working, physical prototype of a loop thermosiphon 3D vapor chamber in accordance with one example.

FIG. 9A is a perspective view of examples of flat tube conduits for a loop thermosiphon 3D vapor chamber.

FIG. 9B is a schematic, cross-sectional view of the loop thermosiphon 3d vapor chamber of FIG. 5, illustrating flat tube conduits.

FIG. 9C is a schematic, cross-sectional view of a different loop thermosiphon 3D vapor chamber, illustrating larger, rounded tube conduits.

FIG. 10A is a perspective view of the header of the loop thermosiphon 3D vapor chamber of FIG. 8.

FIG. 10B is schematic view of the header of FIG. 10A.

FIG. 10C is a schematic view of a header according to another example.

FIG. 10D is a schematic view of a header according to yet another example.

FIG. 11 is a side, schematic cross-sectional view of an extruded tube conduit inserted into stamped sheets that contain collars in accordance with one example.

FIG. 12 is a schematic, perspective view of a reinforcement plate in accordance with one example.

FIG. 13A is a perspective view of the lower body and evaporator region of the loop thermosiphon 3D vapor chamber of FIG. 8, illustrating extended surfaces on the lower body and evaporator region of the lower body.

FIG. 13B is a further perspective view of the lower body and evaporator region of FIG. 13A.

FIG. 13C is a further perspective view of the lower body and evaporator region of FIG. 13A.

FIG. 14 is a schematic side, cross-sectional view of an evaporator region having a flat powder wick structure.

FIG. 15 is a schematic side, cross-sectional view of an evaporator region having extended powder ribs.

FIG. 16 is a schematic side, cross-sectional view of an evaporator region having extended surfaces and powder ribs positioned over the extended surfaces.

FIG. 17 is a schematic top view of an evaporator region having extended surfaces, a portion of which include rounded posts.

FIG. 18 is a schematic top view of an evaporator region having planar extended surfaces.

FIG. 19 is a schematic top view of an evaporator region having a grid pattern of extended surfaces and pockets.

FIG. 20 is a schematic side, cross-sectional view of extended surfaces in an evaporator region, and a wick structure positioned on the extended surfaces.

FIG. 21 is a schematic perspective view of an evaporator region having extended surfaces and pockets.

FIG. 22 is a schematic top view of the evaporator region of FIG. 21.

FIG. 23 is a schematic top, cross-sectional view of the evaporator region of FIG. 21.

FIG. 24A is a schematic side, cross-sectional view of an evaporator region, illustrating a wall and a moat region.

FIG. 24B is a schematic side, cross-sectional view of an evaporator region, illustrating a powder wick wall that separates a liquid reservoir.

FIG. 25 is a schematic top, cross-sectional view of an evaporator region, illustrating a serpentine wall.

FIG. 26 is a schematic cross-sectional view of a 3D vapor chamber in accordance with another example, without a header and including a single conduit that forms a loop.

FIG. 27 is schematic perspective view of a 3D vapor chamber in accordance with another example, again without a header and including multiple conduits that are arranged in a row.

FIG. 28 is a schematic perspective view of a 3D vapor chamber in accordance with another example, again without a header and including multiple conduits that are arranged in a staggered pattern.

FIG. 29 is a schematic perspective view of a 3D vapor chamber in accordance with another example, again without a header and including multiple conduits that are arranged underneath other conduits.

FIG. 30 is a schematic front view of a 3D vapor chamber in accordance with another example, having fins that extend from a header.

DETAILED DESCRIPTION

Heat Pipe

FIG. 1 schematically illustrates an example of a heat pipe 10 having an evaporator region 12, a condenser region 14, and an adiabatic region 16 positioned between the evaporator region 12 and the condenser region 14. In the illustrated example, the heat pipe 10 is a closed, hollow heat pipe 10 having a body 18 (e.g., a generally cylindrical body with rounded, closed ends) that defines a hollow interior 20. The body 18 is formed from a thermally conductive material (e.g., copper or other thermally conductive metals). The hollow interior 20 houses a working fluid (e.g., water) in vaporized form and/or liquid form. The heat pipe 10 further includes at least one wick structure 22 positioned within the hollow interior 20. The wick structure 22 extends at least partially (e.g., continuously) along an interior wall of the body 18 from the condenser region 14 to the evaporator region 12.

During use, heat is inputted at the evaporator region 12 (e.g., from a heat source such as an electronic heat source), causing the working fluid to evaporate into a vapor and move through the hollow interior 20 to the condenser region 14. There, the working fluid condenses, and heat is dissipated from the heat pipe 10. The condensed working fluid returns along the wick structure 22 (e.g., through capillary action) back to the evaporator region 12, undergoing pressure losses as it returns to the evaporator region 12.

2D Vapor Chamber

FIG. 2 schematically illustrates an example of a vapor chamber 24 (e.g., a two-dimensional (“2D”) vapor chamber) having an evaporator region 26, a condenser region 28, and an adiabatic region 30 positioned between the evaporator region 26 and the condenser region 28. In the illustrated example, the 2D vapor chamber 24 is a closed, hollow vapor chamber 24 having a body 32 (e.g., a generally rectangular body) that defines a hollow interior 34. The hollow interior 34 houses a working fluid (e.g., water). The 2D vapor chamber 24 further includes at least one wick structure 36 positioned within the hollow interior 34. The wick structure 36 extends at least partially (e.g., continuously) along an interior wall or walls of the body 32 from the condenser region 28 to the evaporator region 26. In the illustrated example, the 2D vapor chamber 24 includes a lower wall 38, an upper wall 40, a first side wall 42, and a second side wall 44. The evaporator region 26 is positioned along one portion of the lower wall 38, and the condenser region 28 is positioned along one portion of the upper wall 40. The wick structure 36 extends continuously along an interior surface of each of the lower wall 38, the upper wall 40, the first side wall 42, and the second side wall 44, although in other examples the wick structure 36 does not extend continuously, and/or extends only along a portion of the lower wall 38, the upper wall 40, the first side wall 42, and/or the second side wall 44.

With continued reference to FIG. 2, a set of air-cooled fins 46 extend away (e.g., vertically upwardly and perpendicularly) from the upper wall 40 at the condenser region 28. The air-cooled fins 46 are made, for example, of a thermally conductive material (e.g., copper, aluminum, or other thermally conductive metals), such that heat from the condenser region 28 passes upwardly into and through the air-cooled fins 46. Air is directed across and/or through the set of air-cooled fins 46 (e.g., through gaps between the air-cooled fins 46) to facilitate removal of the heat moving upwardly into the air-cooled fins 46 from the condenser region 28.

During use, heat is inputted at the evaporator region 26 (e.g., from a heat source such as an electronic heat source), causing the working fluid to evaporate into a vapor and move through the hollow interior 34 to the condenser region 28. There, the working fluid condenses, and heat is dissipated from the vapor chamber 24, and through the air-cooled fins 46. The condensed working fluid returns along the wick structure 36 (e.g., through capillary action and/or gravity) back to the evaporator region 26, undergoing pressure losses as it returns to the evaporator region 26. As illustrated in FIG. 2, the condensed working fluid returns along multiple paths. A portion of the condensed working fluid returns along a first path in the wick structure 36, laterally along the upper wall 40 and then vertically down the first side wall 42 to the evaporator region 26. Another portion of the condensed working fluid returns along a second path in the wick structure 36, vertically down along the second side wall 44 and then laterally along the lower wall 38 to the evaporator region 26.

In some examples, the vapor chamber 24 may have a higher heat rate, higher heat flux, and/or a lower evaporator and condenser thermal resistance as compared to other devices, such as the heat pipe 10 described above.

Vapor Chamber with Heat Pipe

FIG. 3 schematically illustrates an example of a thermal device 48 having a vapor chamber 50 (e.g., a 2D vapor chamber) and a heat pipe 52 coupled to the 2D vapor chamber 50, thereby forming a vapor chamber with heat pipe. The thermal device 48 includes an evaporator region 54, a condenser region 56, and an adiabatic region 58 positioned between the evaporator region 54 and the condenser region 56.

The 2D vapor chamber 50 may be similar or identical to the 2D vapor chamber 24 described above. As seen in FIG. 3, at least a portion of the 2D vapor chamber 50 defines the evaporator region 54 of the thermal device 48. The 2D vapor chamber 50 is a closed, hollow 2D vapor chamber 50 that defines a hollow interior which houses a working fluid (e.g., water). The 2D vapor chamber 50 further includes at least one wick structure 60 positioned within the hollow interior. The wick structure 60 extends at least partially (e.g., continuously) along an interior wall or walls.

The heat pipe 52 is coupled to the 2D vapor chamber 50 (e.g., to a top wall of the vapor chamber 50). The heat pipe 52 defines its own hollow interior, and may include a wick structure 62 positioned within the hollow interior, and also working fluid within the hollow interior. In the illustrated example, the heat pipe 52 is bent and/or curved, such that a central portion of the heat pipe 52 is coupled to (e.g., near to or in contact with) the 2D vapor chamber 50, to receive heat from the 2D vapor chamber 50, and ends 64 of the heat pipe 52 extend away (e.g., upwardly) from the 2D vapor chamber 50. In the illustrated example, one or both of the ends 64 define the condenser region 56 of the thermal device 48.

With continued reference to FIG. 3, a set of air-cooled fins 66 extend away (e.g., horizontally) from the ends 64 at the condenser region 56. The air-cooled fins 66 are made, for example, of a thermally conductive material (e.g., copper, aluminum, or other thermally conductive metals), such that heat from the condenser region 56 passes into and through the air-cooled fins 66. Air is directed across and/or through the set of air-cooled fins 66 (e.g., through gaps between the air-cooled fins 66) to facilitate removal of the heat moving into the air-cooled fins 66 from the condenser region 56.

During use, heat is inputted at the evaporator region 54 (e.g., from a heat source such as an electronic heat source), causing the working fluid in the 2D vapor chamber 50 and/or the heat pipe 52 to evaporate into a vapor. The working fluid in the heat pipe 52 condenses at the condenser region 56, and heat is dissipated through the air-cooled fins 66. The condensed working fluid in the heat pipe 52 returns along the wick structure 62 (e.g., through capillary action and/or gravity) back to the central region of the heat pipe 52. In the 2D vapor chamber 50, the vapor condenses (e.g., at a location(s) away from the evaporator region 54), and then returns back to the evaporator region (e.g., via the wick structure 60).

In some examples, the overall thermal device 48 may have a lower condenser thermal resistance as compared to other devices, such as the vapor chamber 24 described above.

Round Tube 3D Vapor Chamber

FIG. 4 schematically illustrates an example of a round tube 3D vapor chamber 68 (e.g., a three-dimensional “3D” vapor chamber) having an evaporator region 70, a condenser region 72, and an adiabatic region 74 positioned between the evaporator region 70 and the condenser region 72. The 3D vapor chamber 68 is a closed, hollow vapor chamber 68 having a main (e.g., lower) chamber 76, and at least one round tube 78 that extends (e.g., perpendicularly) from the main chamber 76. The main chamber 76 defines the evaporator region 70, and the round tube or tubes 78 define the condenser region 72.

The vapor chamber 68 houses a working fluid (e.g., water), and includes at least one wick structure 80. The wick structure 80 extends at least partially (e.g., continuously) along an interior wall or walls from the condenser region 72 to the evaporator region 70. In the illustrated example, the wick structure 80 extends at least partially into one or more of the round tubes 78, and also at least partially into the main chamber 76. Additionally, in the illustrated example, portions of the wick structure 80 extend through (e.g., entirely through) the hollow interior space of the main chamber 76, to connect to portions of the wick structure 80 that are positioned along a lower wall of the main chamber 76.

With continued reference to FIG. 4, a set of air-cooled fins 82 extend away (e.g., horizontally) from the round tubes 78 at the condenser region 72. The air-cooled fins 82 are made, for example, of a thermally conductive material (e.g., copper, aluminum, or other thermally conductive metals), such that heat from the condenser region 72 passes into and through the air-cooled fins 82. Air is directed across and/or through the set of air-cooled fins 82 (e.g., through gaps between the air-cooled fins 82) to facilitate removal of the heat moving into the air-cooled fins 82 from the condenser region 72.

During use, heat is inputted at the evaporator region 70 (e.g., from a heat source such as an electronic heat source), causing the working fluid to evaporate into a vapor. The working fluid condenses at the condenser region 72, and heat is dissipated through the air-cooled fins 82. The condensed working fluid returns along the wick structure 80 (e.g., through capillary action and/or gravity) back to the evaporator region 70, undergoing pressure losses as it returns to the evaporator region 70.

In some examples, the 3D vapor chamber 68 may have a lower condenser thermal resistance as compared to other devices, such as the thermal device 48 described above.

3D Vapor Chambers with Loop Thermosiphons

FIG. 5 schematically illustrates one example of a 3D vapor chamber 86 (e.g., a flat tube 3D vapor chamber) with loop thermosiphon. In the illustrated example, the 3D vapor chamber 86 includes an evaporator region 90, a condenser region 94, and an adiabatic region 98 (or regions 98) positioned between the evaporator region 90 and the condenser region 94. The 3D vapor chamber 86 also includes a lower body 102 that defines a hollow interior 106, and a recessed well 110. The recessed well 110 is located generally centrally along the lower body 102, although in other examples the recessed well 110 is positioned laterally closer to one end of the lower body 102 than another end of the lower body 102. The evaporator region 90 is defined at least in part by the recessed well 110. In other examples, the lower body 102 does not include a recessed well 110.

With continued reference to FIG. 5, the recessed well 110 includes a lower well wall 114, a first side well wall 118 that extends at oblique angle (e.g., 30 degrees, 45 degrees, 60 degrees, or other angles) relative to the lower well wall 114, and a second side well wall 122 that extends at oblique angle (e.g., 30 degrees, 45 degrees, 60 degrees, or other angles) relative to the lower well wall 114. While not illustrated, the recessed well 110 may also include a third side well wall and/or a fourth side well wall that also angle (e.g., inwardly) down toward the lower well wall 114. Other examples include different shapes and/or sizes of a recessed well 110 than that illustrated, including recessed wells 110 having other numbers and angles of side well walls, or include no well at all.

With continued reference to FIG. 5, the evaporator region 90 is defined by a portion of the lower well wall 114. During use, the lower well wall 114 is in direct (or indirect) contact with a heat source 126 (e.g., an electronic heat source such as a microprocessor), such that heat from the heat source 126 moves upwardly through the evaporator region 90 and through the lower well wall 114, toward the hollow interior 106 of the lower body 102. In other examples, the evaporator region 90 is defined at least in part by the first side well wall 118, or the second side well wall 122.

With continued reference to FIG. 5, the lower body 102 also defines at least one liquid reservoir that receives condensed working fluid (e.g., water), and/or directs the condensed working fluid to the recessed well 110. In the illustrated example, the lower body 102 includes a first liquid reservoir 130 positioned to one side of the recessed well 110, and a second liquid reservoir 134 positioned on an opposite side of the recessed well 110. Each of the first and second liquid reservoirs 130, 134 has a generally rectangular cross-sectional shape, as seen in FIG. 5, although other examples include different shapes and sizes than that illustrated. In some examples, the first and second liquid reservoirs 130, 134 are fluidly connected, such that they form a single overall liquid reservoir that surrounds the recessed well 110. In some examples, the lower body 102 defines more than two liquid reservoirs.

As illustrated in FIG. 5, the first liquid reservoir 130 includes a first lower reservoir wall 136, a first upper reservoir wall 138, and a first side reservoir wall 142. During use, condensed working fluid accumulates along the first lower reservoir wall 136, rising toward the first upper reservoir wall 138. The first liquid reservoir 130 also includes a first boundary wall 146 that extends upwardly (e.g., vertically) from the first lower reservoir wall 136, and terminates before reaching the first upper reservoir wall 138. The first boundary wall 146 extends upwardly from the first lower reservoir wall 136 at an intersection between the first lower reservoir wall 136 and the first side well wall 118. In other examples, the first boundary wall 146 extends from the first lower reservoir wall 136 at a different location (e.g., laterally away from the intersection between the first lower reservoir wall 136 and the first side well wall 118). In yet other examples, the first boundary wall 146 extends from the recessed well 110 (e.g., from the first side well wall 118, or another wall).

The second liquid reservoir 134 similarly includes a second lower reservoir wall 150, a second upper reservoir wall 154, and a second side reservoir wall 158. The first upper reservoir wall 138 and the second upper reservoir wall 154 are integrally formed together as a single piece, and define portions of an overall upper reservoir wall (e.g., the first upper reservoir wall 138 merging into the second upper reservoir wall 154 generally at a location directly above the recessed well 110). In other examples, the first upper reservoir wall 138 are a separate wall from the second upper reservoir wall 154.

During use, condensed working fluid accumulates along the second lower reservoir wall 150, rising toward the second upper reservoir wall 154. The second liquid reservoir 134 also includes a second boundary wall 162 that extends upwardly (e.g., vertically) from the second lower reservoir wall 150, and terminates before reaching the second upper reservoir wall 154. The second boundary wall 162 extends upwardly from the second lower reservoir wall 150 at an intersection between the second lower reservoir wall 150 and the second side well wall 122. In other examples, the second boundary wall 162 extends from the second lower reservoir wall 150 at a different location (e.g., laterally away from the intersection between the second lower reservoir wall 150 and the second side well wall 122).

With continued reference to FIG. 5, the first boundary wall 146 and the second boundary wall 162 are integrally formed together as a single piece, and are each part of a single boundary wall that extends entirely around the recessed well 110. A height of the first boundary wall 146 (e.g., as measured vertically upwardly from the first lower reservoir wall 136) is identical to a height of the second boundary wall 162 (e.g., as measured vertically upwardly from the second lower reservoir wall 150). In other examples, multiple separate boundary walls are provided, and/or a height of the first boundary wall 146 is different than a height of the second boundary wall 162. In yet other examples, the first boundary wall 146 and/or the second boundary wall 162 are omitted entirely.

With continued reference to FIG. 5, the 3D vapor chamber 86 further includes at least one wick structure 166 positioned within the hollow interior 106 of the lower body 102. The wick structure 166 is formed, for example, from wire or screen mesh, sintered powder metal, or other suitable material. In some examples, the wick structure 166 includes one or more grooves formed (e.g., machined) into the wall or walls of the lower body 102. Different wick structures 166 have varying permeability and maximum capillary pressures, which affects the amount of liquid flow back to the evaporator region 90.

In some examples, the wick structure 166 may extend entirely along the hollow interior 106, and/or the hollow interior 106 may include additional wick structures. Additionally, in some examples, the wick structure 166 (or other structure positioned within the hollow interior 106) may aid in freeze/thaw tolerance, inhibiting or preventing the liquid from freezing and/or expanding, and potentially damaging the thermal device.

With continued reference to FIG. 5, the wick structure 166 extends at least partially (e.g., continuously) along an interior wall or walls of the lower body 102. The wick structure 166 extends continuously along an interior of the lower well wall 114, and also along an interior of each of the first side well wall 118 and the second side well wall 122, such that the entire recessed well 110 is coated by the wick structure 166. In other examples, the wick structure 166 extends only along a portion of the lower well wall 114, along a portion of the first side well wall 118, and/or along a portion of the second side well wall 122.

The wick structure 166 also includes a first peripheral portion 170 that extends upwardly out of the recessed well 110 and wraps up and over the first boundary wall 146. The first peripheral portion 170 rises up toward (and in some instances physically contacts) the first upper reservoir wall 138, in an area above a terminal end of the first boundary wall 146. The first peripheral portion 170 also extends down and laterally alongside the first boundary wall 146, toward (and in some instances physically contacting) the first lower reservoir wall 136.

Similarly, the wick structure 166 also includes a second peripheral portion 174 that extends upwardly out of the recessed well 110 and wraps up and over the second boundary wall 162. The second peripheral portion 174 rises up toward (and in some instances physically contacts) the second upper reservoir wall 154, in an area above a terminal end of the second boundary wall 162. The second peripheral portion 174 also extends down and laterally alongside the second boundary wall 162, toward (and in some instances physically contacting) the second lower reservoir wall 150.

In the illustrated example, the first peripheral portion 170 and the second peripheral portion 174 are integrally formed together as a single piece, and are each part of a single periphery of the wick structure 166 that extends entirely around the recessed well 110. In other examples, multiple separate peripheral portions of the wick structure 166 are provided. In yet other examples, at least a portion of the wick structure 166 (e.g., the first and/or second peripheral portions 170, 174) is omitted entirely. In some examples, the wick structure 166 may replace the first liquid reservoir 130 and/or the second liquid reservoir 134, and may extend for example to an end of the lower body 102.

With continued reference to FIG. 5, the 3D vapor chamber 86 also includes a plurality of conduits (e.g., vertical, flat tubes) 178 that are coupled to the lower body 102, and are in fluid communication with the hollow interior 106 of the lower body 102. Each of the conduits 178 is a hollow tube (e.g., hollow flat tube, hollow cylindrical tube, etc.) coupled directly either to the first upper reservoir wall 138 or the second upper reservoir wall 154. In some examples, one or more of the conduits 178 is a flattened tube, is extruded, and/or is a smooth or grooved tube. In the illustrated example, the conduits 178 extend parallel to one another, and each of the conduits 178 is sized, shaped, and positioned to direct a flow (or flows) of working fluid (e.g., in liquid form and/or vaporized form) vertically upwardly and/or vertically downwardly.

Some of the conduits 178 have a width “W” that is different than other conduits 178. For example, the two illustrated conduits 178 located directly above the evaporator region 90 have a width that is larger than the width of the conduits 178 that are located directly over the first liquid reservoir 130 or the second liquid reservoir 134. In other examples, the conduits 178 located directly above the evaporator region 90 have a width that is smaller than the width of the conduits 178 that are located directly over the first liquid reservoir 130 or the second liquid reservoir 134. In yet other examples, each of the conduits 178 in the 3D vapor chamber 86 has an identical width. Additionally, while the illustrated conduits 178 extend parallel to one another, in other examples at least one of the conduits does not extend parallel to another one of the conduits 178.

Overall, the conduits 178 are sized and shaped such that a different (e.g., larger) aggregate cross-sectional area of conduits 178 for vapor flow exists than for return liquid flow in the 3D vapor chamber 86, although other examples include other arrangements and desired flows. In some examples, the vaporized working fluid and the condensed, liquid working fluid flow in the same direction in the majority, or vast majority, of the 3D vapor chamber 86 (e.g., in a majority of the conduits 178 in the 3D vapor chamber 86). In yet other examples, the vaporized working fluid and the condensed, liquid working fluid do not flow in the same direction in the majority, or vast majority, of the 3D vapor chamber 86. In some examples, the vaporized working fluid and the condensed, liquid working fluid do not flow in the same direction in any portion of the 3D vapor chamber 86, or only flow in the same direction in a small portion of the 3D vapor chamber 86.

In some examples, at least one of the conduits 178 extends down and touches a lower wall or filler material (e.g., screen) of a liquid reservoir, a lower wall or wick of an adiabatic region, and/or any portion of an evaporator. For example, in the illustrated example one of the conduits 178 may extend down and touch the first lower reservoir wall 136, or the second lower reservoir wall 150, or may touch a portion of the wick structure 166. The conduit 178 may instead extend down into the lower body 102, but terminate slightly above the first lower reservoir wall 136 (e.g., within or above liquid that accumulated in the first liquid reservoir 130), the second lower reservoir wall 150 (e.g., within or above liquid that accumulated in the second liquid reservoir 134), or the wick structure 166. In some examples, at least one of the conduits 178 may extend down and touch, or terminate slightly above, the evaporator region 90, or any of the lower walls (e.g., walls 114, 118, 122) of the recessed well 110.

With continued reference to FIG. 5, the 3D vapor chamber 86 further includes at least one header 182 positioned above the lower body 102 and the conduits 178, and in fluid communication with the conduits 178. Each of the conduits 178 extends from the lower body 102 to the header(s) 182. Each of the conduits 178 has an identical vertical height “H” (e.g., as measured between the lower body 102 and the header 182, along a direction that is perpendicular to the direction of the width “W”), although in other examples at least one of the conduits 178 has a height that is different than a height of a different one of the conduits 178.

The header 182 includes a header upper wall 186, a header lower wall 190, a first header side wall 194, and a second header side wall 198, thereby defining a rectangular cross-sectional shape, although other examples include other shapes than that illustrated. The header 182 also defines interior volume 202. The header 182 is sized, shaped, and positioned such that at least a portion of the working fluid (e.g., in liquid form and vaporized form) flows through the interior volume 202 (e.g., laterally along a direction that is perpendicular to a flow of working fluid in the conduits 178).

With continued reference to FIG. 5, the condenser region 94 of the 3D vapor chamber 86 includes at least one air-cooled fin 206 (e.g., plate, protrusion, or other structure that facilitates a movement of heat to a surface on the structure, where the heat may then quickly be dissipated by movement of air or other fluid across the surface). In the illustrated example, the 3D vapor chamber 86 includes multiple sets (e.g., stacks) of air-cooled fins 206. Each of the sets includes a stack of air-cooled fins 206 (e.g., stacked vertically and/or horizontally). In some examples, the air-cooled fins 206 are inserted laterally into the 3D vapor chamber. The air-cooled fins 206 are inserted, for example, between flat surfaces of the conduits 178. As seen in FIG. 5, the sets of air-cooled fins 206 are separated by the conduits 178. Various types of air-cooled fins 206 may be used, including for example C fins, folded fins, and/or lanced offset fins. In some examples, the 3D vapor chamber 86 includes different types of air-cooled fins 206 in different locations, allowing for different fin pitch in different sections of the condenser region 94. For example, some 3D vapor chambers 86 may also, or alternatively, include one or more air-cooled fins 206 that are positioned on top of the header 182. The air-cooled fins 206 on the header 182 may extend vertically upwardly, and/or may otherwise be positioned to receive an air-flow, and/or dissipate heat. Placing air-cooled fins 206 on the header 182 may allow the overall 3D vapor chamber 86 to be shorter, have less weight, be made cheaper, have higher capacity, have lower pressure drop, and/or have lower thermal resistance than other 3D vapor chambers.

During use, air is directed through the sets of air-cooled fins 206 (e.g., through spaces or gaps between each of the air-cooled fins 206), to facilitate condensation of the working fluid, and/or to facilitate removal of heat from the 3D vapor chamber 86). Air (e.g., from a powered air source, such as a fan or fans) is directed through the sets of air-cooled fins 206 along a direction that is perpendicular to the flow of working fluid through the conduits 178 (e.g., from left to right in FIG. 5, or into the page in FIG. 5). In other examples the sets of air-cooled fins 206 include other numbers of fins 206 and/or set of fins 206 than that illustrated, and other direction of air flow.

With continued reference to FIG. 5, during use the 3D vapor chamber 86 may be coupled to the heat source 126. Heat from the heat source 126 is directed vertically upwardly into the evaporator region 90 along the lower well wall 114. The heat warms the working fluid that is disposed within the recessed well 110 (e.g., the working fluid disposed within the wick structure 166 and/or the working fluid disposed generally within the recessed well 110 above or otherwise adjacent the wick structure 166). Once the working fluid is heated, the working fluid vaporizes, and begins to rise vertically, passing upwardly out of the recessed well 110 and into one or more of the conduits 178. The vaporized working fluid may then split (as shown by the arrows in FIG. 3), such that a portion of the vaporized working fluid moves vertically upwardly through one of the conduits 178 located above the recessed well 110, and another portion of the vaporized working fluid moves vertically upwardly through another one of the conduits 178 located above the recessed well 110. The first peripheral portion 170 and second peripheral portion 174 of the wick structure 166 block the vaporized working fluid from moving laterally past these two conduits 178, and force the vapor to thereby flow upwardly into one or both of these two conduits 178.

The vaporized working fluid eventually reaches the header 182, and is then redirected (e.g., laterally to the left or right in FIG. 3). In some examples, the vaporized working fluid begins to at least partially condense in the conduits 178 directly above the recessed well 110, and/or at least partially condenses in the header 182 (e.g., due to cooling effects created by air moving across the nearby air-cooled fins 206 or the header 182). In the illustrated example, a small portion (e.g., less than 50%, less than 40%, less than 30%, less than 20%, less than 10%, less than 5%, etc.) of the vaporized working fluid begins to condense in the conduits 178 directly above the recessed well 110, and/or in the header 182. In other examples, at least 50%, at least 60%, at least 70%, or at least 80%, or at least 90% of the vaporized working fluid begins to condense in the conduits 178. In some examples, the working fluid remains entirely in a vaporized state within the conduits 178 and/or within the header 182 as the working fluid flows upwardly toward a top of the 3D vapor chamber 86.

With continued reference to FIG. 5, the flow of working fluid continues, as seen via the arrows in FIG. 5, such that the working fluid begins to be redirected again, in a vertically downward direction, through one or more of the conduits 178 that are positioned above the first liquid reservoir 130 and/or the second liquid reservoir 134. The working fluid (e.g., in vaporized form, condensed liquid form, or both) moves vertically down through three conduits 178 above the first liquid reservoir 130, and through three conduits 178 above the second liquid reservoir 134. Other examples include different numbers and arrangements of conduits and liquid reservoirs. In some examples, one or more of the conduits 178 extends entirely down and contacts the wick structure 166. With continued reference to FIG. 3, as the working fluid moves vertically downwardly through the conduits 178, the air passing through the adjacent air-cooled fins 206 cools the working fluid, removing heat such that the working fluid condenses within the conduits 178. The condensed working fluid accumulates as droplets of water along the interior surfaces (e.g., walls) of the conduits 178. The overall flow of working fluid, and/or gravity, pulls on the droplets, forcing them to eventually drop into the lower body 102 and into the first liquid reservoir 130 and/or the second liquid reservoir 134. As noted above, in some examples the working fluid may begin to condense in the conduits 178 directly above the recessed well 110, and/or in the header 182. Accordingly, some droplets of water may form within these conduits 178, and/or within the header 182, and be pulled down (e.g., with the assistance of gravity) back to the lower body 102 (e.g., back directly into the recessed well 110 or into the first liquid reservoir 130 or second liquid reservoir 134). Once the condensed, liquid working fluid has accumulated in the lower body 102, the liquid then rises and/or begins to contact the wick structure 166. The wick structure 166 (e.g., through capillary action) pulls the liquid from the first liquid reservoir 130 and/or the second liquid reservoir 134 up over the first boundary wall 146 and/or the second boundary wall 162 and back into the recessed well 110. This process then continues, and repeats, such that the working fluid is continuously flowing through the pathways described above, and heat is continuously removed from the heat source 126.

Overall, the 3D vapor chamber 86 is unique, for example, in that the vapor and liquid phases may travel together through the condenser region 94, and the condensate may be driven back to one or more reservoirs (e.g., the first liquid reservoir 130 and/or the second liquid reservoir 134) by the downwards (with gravity) co-current flow. This technology may achieve better thermal resistance and much greater capacity within the same unit volume.

FIG. 6 schematically illustrates another example of a 3D vapor chamber 210 (e.g., a flat tube) vapor chamber with loop thermosiphon. Similar to the 3D vapor chamber 86, the 3D vapor chamber 210 also includes a lower body 214 that defines a hollow interior 218, and a recessed well 222 located generally centrally along the lower body 214, although in other examples the recessed well 222 is positioned laterally closer to one end of the lower body 214 than another end of the lower body 214. The 3D vapor chamber 210 also includes an evaporator region 226 defined at least in part by the recessed well 222. In other examples, the lower body 214 does not include a recessed well 222.

With continued reference to FIG. 6, the recessed well 222 includes a lower well wall 230, a first side well wall 234 that extends at oblique angle (e.g., 30 degrees, 45 degrees, 60 degrees, or other angles) relative to the lower well wall 230, and a second side well wall 238 that extends at oblique angle (e.g., 30 degrees, 45 degrees, 60 degrees, or other angles) relative to the lower well wall 230. While not illustrated, the recessed well 222 may also include a third side well wall and/or a fourth side well wall that also angle (e.g., inwardly) down toward the lower well wall 230. Other examples include different shapes and/or sizes of a recessed well 222 than that illustrated, including recessed wells having other numbers and angles of side well walls, or include no well at all.

The evaporator region 226 is defined by a portion of the lower well wall 230. During use, the lower well wall 230 is in direct (or indirect) contact with a heat source (e.g., the heat source 126 described above, or a different heat source), such that heat from the heat source moves upwardly through the evaporator region 226 and through the lower well wall 230, toward the hollow interior 218 of the lower body 214. In other examples, the evaporator region 226 is defined at least in part by the first side well wall 234, or the second side well wall 238.

With continued reference to FIG. 6, the lower body 214 also defines at least one liquid reservoir that receives condensed working fluid (e.g., water), and/or directs the condensed working fluid to the recessed well 222. In the illustrated example, the lower body 214 includes a liquid reservoir 242 positioned to one side of the recessed well 222, and a wick structure 246 positioned on an opposite side of the recessed well 222.

With continued reference to FIG. 6, the liquid reservoir 242 includes a first lower reservoir wall 250, a first upper reservoir wall 254, and a first side reservoir wall 258. During use, condensed working fluid accumulates along the first lower reservoir wall 250, rising toward the first upper reservoir wall 254. The liquid reservoir 242 also includes a boundary wall 262 that extends upwardly (e.g., vertically) from the first lower reservoir wall 250, and terminates before reaching the first upper reservoir wall 254. The boundary wall 262 extends upwardly from the first lower reservoir wall 250 near, but laterally spaced from, an intersection between the first lower reservoir wall 250 and the first side well wall 234. In other examples, the boundary wall 262 extends from the first lower reservoir wall 250 at a different location (e.g., directly at the intersection between the first lower reservoir wall 250 and the first side well wall 234). In yet other examples, the boundary wall 262 is omitted.

The wick structure 246 is positioned partially within a portion of the lower body 214 that includes a second lower wall 266, a second upper wall 270, and a second side wall 274. In the illustrated example, the wick structure 246 extends along the second lower wall 266. The wick structure 246 also extends into the recessed well 222, and into a conduit 290. The first upper reservoir wall 254 and the second upper wall 270 are integrally formed together as a single piece, and define portions of an overall upper wall (e.g., the first upper reservoir wall 254 merging into the second upper wall 270 generally at a location directly above the recessed well 222). In other examples, the first upper reservoir wall 254 is a separate wall from the second upper wall 270.

With continued reference to FIG. 6, the wick structure 246 is formed, for example, from wire or screen mesh, sintered powder metal, or other suitable material. In some examples, the wick structure 246 includes one or more grooves formed (e.g., machined) into the wall or walls of the lower body 214.

With continued reference to FIG. 6, the wick structure 246 extends at least partially (e.g., continuously) along an interior wall or walls of the lower body 214. The wick structure 246 extends continuously, for example, along an interior of the lower well wall 230, and also along an interior of each of the first side well wall 234 and the second side well wall 238, such that the entire recessed well 222 is coated by the wick structure 246. In other examples, the wick structure 246 extends only along a portion of the lower well wall 230, along a portion of the first side well wall 234, and/or along a portion of the second side well wall 238.

The wick structure 246 also includes a peripheral portion 282 that extends upwardly out of the recessed well 222 and wraps up and over the boundary wall 262. The peripheral portion 282 rises up toward (and in some instances physically contacts) the first upper reservoir wall 254, in an area above a terminal end of the boundary wall 262. The peripheral portion 282 also extends down and laterally alongside the boundary wall 262, toward (and in some instances physically contacting) the first lower reservoir wall 250. In some examples, the peripheral portion 282 inhibits or prevent vapor from passing therethrough, and thus help to direct a vapor flow within the 3D vapor chamber 210.

With continued reference to FIG. 6, the wick structure 246 (or an entirely separate wick structure) may also extend within at least a portion of one or more conduits 290 within the 3D vapor chamber 210 (e.g., vertically along an inside of a rear conduit 290 as shown in FIG. 4). The wick structure 246 within the conduit 290 facilitates a flow of condensed working fluid down from at least one header 294 and toward the recessed well 222 and the evaporator region 226. As illustrated in FIG. 4, the wick structure 246 extends vertically down below the second upper wall 270, and then changes direction as it moves along the second lower wall 266. In other examples, the wick structure 246 is located in a different location than that illustrated, or extends a different distance, and/or a separate wick structure may be positioned in the conduit 290. In some examples, the wick structure 246 may extend upwardly farther than that illustrated, and/or may extend upwardly only to the second upper wall 270 or to a location above the second upper wall 270 (e.g., into the header 294). In some examples, the wick structure 246 only extends within the conduit 290 itself, or only extends within the lower body 214. Some examples include more than one second wick structure 286. For example, a first wick structure may be positioned in the recessed well 222, and a second wick structure may be positioned within the one of the conduits 290. In yet other examples, the wick structure 246 is omitted entirely. Additionally, in some examples, the wick structure 246 may extend at least partially into the header 294.

With continued reference to FIG. 6, the 3D vapor chamber 210 includes a plurality of the conduits 290. Similar to the conduits 178, the conduits 290 are coupled to the lower body 214, and are in fluid communication with the hollow interior 218 of the lower body 214. Each of the conduits 290 is a hollow tube coupled directly either to the first upper reservoir wall 254 or the second upper wall 270. In some examples, one or more of the conduits 290 is a flattened tube (similar to the flat conduits 178 seen in FIG. 5), is extruded, and/or is a smooth or grooved tube. In the illustrated example, the conduits 290 extend parallel to one another, and each of the conduits 290 is sized, shaped, and positioned to direct a flow (or flows) of working fluid (e.g., in liquid form and/or vaporized form) vertically upwardly and/or vertically downwardly. Some of the conduits 290 may have a width that is different than other conduits 290, and in some examples at least one of the conduits 290 is not parallel to at least another one of the other conduits 290. In the illustrated example, the 3D vapor chamber 210 includes one or more conduits 290 positioned above the recessed well 222, and other conduits 290 positioned above the liquid reservoir 242 and the second upper wall 270. In some examples, one or more of the conduits 290 extends down and physically contacts the wick structure 246. Other examples include different numbers and arrangements of conduits 290.

In some examples, at least one of the conduits 290 extends down and touches a lower wall or filler material of a liquid reservoir, a lower wall or wick of an adiabatic region, and/or any portion of an evaporator. For example, in the illustrated example one of the conduits 290 may extend down and touch the first lower reservoir wall 250, or the second lower wall 266, or may touch a portion of the wick structure 246. The conduit 290 may instead extend down into the lower body 214, but terminate slightly above the first lower reservoir wall 250 (e.g., within or above liquid that accumulated in the liquid reservoir 242), the second lower wall 266, or the wick structure 246. In some examples, at least one of the conduits 290 may extend down and touch, or terminate slightly above, the evaporator region 226, or any of the lower walls (e.g., walls 230, 234, 238) of the recessed well 222.

With continued reference to FIG. 6, the header 294 is positioned above and in fluid communication with the conduits 290, such that at least a portion of the working fluid (e.g., in liquid form and/or vaporized from) flows through an interior volume of the header 294 (e.g., laterally along a direction that is perpendicular to a flow of working fluid in the conduits 290). Each of the conduits 290 extends from the lower body 214 to the header 294. Similar to the conduits 178, each of the conduits 290 has an identical vertical height, although in other examples at least one of the conduits 290 has a height that is different than the height of a different one of the conduits 290.

With continued reference to FIG. 6, the 3D vapor chamber 210 includes a condenser region 298 that includes at least one air-cooled fin 302. In the illustrated example, the 3D vapor chamber 210 includes multiple sets (e.g., stacks) of air-cooled fins 302. Each of the sets includes a stack of air-cooled fins 302 (e.g., stacked vertically and/or horizontally, similar to the air-cooled fins 206 in FIG. 5). The sets of air-cooled fins 302 are separated by the conduits 290. During use, air is directed through the sets of air-cooled fins 302 (e.g., through spaces or gaps between each of the air-cooled fins 302), to facilitate condensation of the working fluid, and/or to facilitate removal of heat from the 3D vapor chamber 210). As seen in FIG. 6, air (e.g. from a powered air source, such as a fan or fans) is directed through the sets of air-cooled fins 302 along a lateral direction (from left to right in FIG. 6), such that the air moves through the stacks of air-cooled fins 302 laterally, and eventually reaches the wick structure 246 and a rear stack of air-cooled fins 302. In such an arrangement, a substantial portion of the condensation of the working fluid may therefore occur along a front side (e.g., left side in FIG. 6) of the vapor chamber 210, because this area of the vapor chamber 210 is first exposed to the cooling air. To more evenly distribute the rate of condensation within the 3D vapor chamber 210, the arrangement and/or spacing of the air-cooled fins 302 may be adjusted (e.g., a density of the air-cooled fins 302 may be altered) in certain areas of the 3D vapor chamber 210. In some examples, a larger number of air-cooled fins 302, or a larger density of air-cooled fins 302, is positioned along a rear of the 3D vapor chamber 210 (i.e., along the right side of FIG. 6), to facilitate the even distribution of cooling and condensing occurring in the 3D vapor chamber 210. Thus, one stack of air-cooled fins 302 may have a different density of air-cooled fins 302 than another stack. Additionally, or alternatively, the density of air-cooled fins 302 may vary itself within a single stack of the air-cooled fins 302. Various types of air-cooled fins 302 may be used, including for example C fins, folded fins, and/or lanced offset fins. During assembly, the air-cooled fins 302 may be inserted between flat surfaces of the conduits 290. In some examples, the 3D vapor chamber 210 includes different types of air-cooled fins 302 in different locations, allowing for different fin pitch in different sections of the condenser region 298. Changing the fin pitch or the condenser arrangement has the goal of achieving the lowest thermal resistance for the given air-side pressure drop target, and seeks to optimize condenser performance. Some 3D vapor chambers 210 may also, or alternatively, include one or more air-cooled fins 302 that are positioned on top of the header 294. The air-cooled fins 302 on the header 294 may extend vertically upwardly, and/or may otherwise be positioned to receive an air-flow, and/or dissipate heat. Placing air-cooled fins 302 on the header 294 may allow the overall 3D vapor chamber 210 to be shorter, have less weight, be made cheaper, have higher capacity, have lower pressure drop, and/or have lower thermal resistance than other 3D vapor chambers 210.

With continued reference to FIG. 6, at least a portion of the air-cooled fins 302 (e.g., one stack of air-cooled fins 302) may be relatively long in the air flow direction (i.e., in a left to right direction as seen in FIG. 4), as compared to other portions of the air-cooled fins 302. As a result, a high amount of vapor may flow to the front of the air-cooled fins 302.

In the illustrated example, the conduits 290 include one or more conduits 290 near the inflow of air, which aid in pulling off and draining some amount of liquid, thus reducing the amount of condensate entering the front of the two conduits 290 (i.e., the conduit to the far left in FIG. 6). As described above, the last or rear conduit 290 (i.e., the conduit 290 to the far right in FIG. 6) may include a portion of the wick structure 246 to aid liquid return back to the evaporator region 226. The wick structure 246 may feed the recessed well 222 and the evaporator region 226, and also block vapor from entering the liquid reservoir 242, while allowing vapor to flow through the lower body 214 to the downstream end of the air-cooled fins 302.

With continued reference to FIG. 6, during use the 3D vapor chamber 210 is coupled to the heat source (e.g., heat source 126 or another heat source). Heat from the heat source 126 is directed vertically upwardly into the evaporator region 226 along the lower well wall 230. The heat warms the working fluid that is disposed within the recessed well 222 (e.g., the working fluid disposed within the wick structure 246 and/or the working fluid disposed generally within the recessed well 222 above or otherwise adjacent the wick structure 246). Once the working fluid is heated, the working fluid vaporizes, and begins to rise vertically, passing upwardly out of the recessed well 222 and into one or more of the conduits 290. For example, as seen by the arrows in FIG. 6, the vaporized working fluid may split, such that a portion of the vaporized working fluid moves vertically upwardly through one of the conduits 290 located above the recessed well 222, and other portions of the vaporized working fluid move vertically upwardly through other conduits 290.

The vaporized working fluid eventually reaches the header 294, and is then redirected (e.g., laterally to the left or right in FIG. 6). In some examples, the vaporized working fluid begins to at least partially condense in the conduits 290 directly above the recessed well 222 and/or above the wick structure 246, and/or at least partially condenses in the header 294 (e.g., due to cooling effects created by air moving across the nearby air-cooled fins 302 or the header 294). In the illustrated example, a small portion (e.g., less than 50%, less than 40%, less than 30%, less than 20%, less than 10%, less than 5%, etc.) of the vaporized working fluid begins to condense in the conduits 290 directly above the recessed well 222 and/or the second upper wall 270, and/or in the header 294. In other examples, at least 50%, at least 60%, at least 70%, or at least 80%, or at least 90% of the vaporized working fluid begins to condense in the conduits 290. In some examples, the working fluid remains entirely in a vaporized state within the conduits 290 and/or within the header 294 as the working fluid flows upwardly toward a top of the 3D vapor chamber 210. In some examples, the vaporized working fluid and the condensed, liquid working fluid flows in the same direction in the majority, or vast majority, of the 3D vapor chamber 210 (e.g., in a majority, or not, of the conduits 290 in the 3D vapor chamber 210). In yet other examples, the vaporized working fluid and the condensed, liquid working fluid do not flow in the same direction in the majority, or vast majority, of the 3D vapor chamber 210. In some examples, the vaporized working fluid and the condensed, liquid working fluid do not flow in the same direction in any portion of the 3D vapor chamber 210, or only flow in the same direction in a small portion of the 3D vapor chamber 210.

With continued reference to FIG. 6, the flow of working fluid continues, as seen via the arrows in FIG. 6, such that the working fluid begins to be redirected again, in a vertically downward direction, through one or more of the conduits 290 that are positioned above the liquid reservoir 242 and/or the second upper wall 270. In the illustrated example, the working fluid (e.g., in liquid form and/or vaporized form) moves vertically down through two conduits 290 above the liquid reservoir 242. Condensed portions of the working fluid move down through the second wick structure 286 (e.g., from droplets that have accumulated within the header 294). Other examples include different numbers and arrangements of conduits and liquid reservoirs and flows of working fluid.

With continued reference to FIG. 6, as the working fluid moves vertically downward, the air passing through the adjacent air-cooled fins 302 cools the working fluid, removing heat, such that the working fluid condenses within the conduits 290. The condensed working fluid accumulates as droplets of water along the interior surfaces (e.g., walls) of the conduits 290. The overall flow of working fluid, and/or gravity, and/or a wicking action in the second wick structure 286, pulls on the droplets, forcing them to eventually drop into the lower body 214 and into the wick structure 246. As noted above, in some examples the working fluid may also begin to condense in the conduit or conduits 290 directly above the recessed well 222, and/or in the header 294. Accordingly, some droplets of water may form within these conduits 290, and/or within the header 294, and be pulled down (e.g., with the assistance of gravity) directly back to the lower body 214 (e.g., back directly into the recessed well 222 or into the liquid reservoir 242). Once the condensed, liquid working fluid has accumulated in the lower body 214, the liquid may rise and/or begin to contact a portion of the wick structure 246. The wick structure 246 (e.g., through capillary action) pulls the liquid from the liquid reservoir 242 up over the boundary wall 262 and back into the recessed well 222. This process continues, and repeats, such that the working fluid is continuously flowing through the pathways described above, and heat is continuously removed from the heat source.

Overall, the 3D vapor chamber 210 is unique, for example, in that the vapor and liquid phases may travel together through the condenser region 298, and the condensate may be driven back to one or more reservoirs (e.g., the reservoir 242) by the downwards (with gravity) co-current flow. This technology may achieve better thermal resistance and much greater capacity within the same unit volume.

The 3D vapor chambers described herein (e.g., including the 3D vapor chambers 68, 86, or 210) may generally define a relatively large chamber filled mostly with working fluid. While the 3D vapor chambers described and illustrated are shown extending in an upright, vertical orientation, the 3D vapor chambers may be angled or oriented at other angles. In some examples, the 3D vapor chambers are filled mostly with vaporized working fluid, and a smaller amount of condensate. The vapor chamber may incorporate one or more wick structures to draw the condensed liquid back to the evaporator region, and/or may take advantage of gravitational forces to aid in liquid return by locating the condenser region physically higher than the evaporator region. By taking advantage of both the draw of the vapor caused by the condensing surface, and the draw of the liquid caused by gravity or a wick structure, an overall loop thermosiphon may be established by routing the vapor to a higher elevation header before sending the working fluid back down into a condenser, where both the vapor momentum and gravitational forces will act in the same direction to drain the liquid condensate back into the liquid reservoir. The liquid reservoir may then feed a wick, which resupplies the evaporator region by capillary action, while simultaneously blocking the vapor from traveling into the liquid reservoir. This may form a “loop thermosiphon” within the 3D vapor chamber. Additionally, and as noted above, some of the 3D vapor chambers described herein may include one header, or may for example include more than one header. For example, some conduits may be coupled to one header, while other conduits may be coupled to another header, or all conduits may be coupled to a same header. The multiple headers may, for example, direct a flow of working fluid to one or more condenser regions and one or more stacks of air-cooled fins.

The 3D vapor chambers described herein may also include one or more wick structures that extend into and/or within one or more of the conduits, and/or one or more of the headers, to facilitate flow of condensed working fluid, and/or block vaporized working fluid. For example, and as described above, the 3D vapor chamber 210 includes a wick structure 246 that is positioned along the evaporator region 226. The wick structure 246 includes a peripheral portion 282 that extends upwardly toward one of the conduits 290, and may for example abut a lower end of the conduit 290 (or a location near a lower end of the conduit) at the first upper reservoir wall 254. The peripheral portion 282 helps to block a flow of vaporized working fluid in at least one direction (e.g., laterally) within the 3D vapor chamber. In some examples, and as described above, the wick structure 246 may extend upwardly even farther, into the conduit 290 itself. As illustrated in FIG. 4, the wick structure 246 may extend within one of the conduits 290 (e.g., within the rear conduit, and/or generally away from the condenser region or regions of the 3D vapor chamber where most of the condensation is occurring). The wick structures described herein may be present in various regions, including the lower body, the conduits, and/or the header.

Use of one or more wick structures, in a conduit or elsewhere, may facilitate flow of condensed liquid working fluid in one direction (e.g., vertically downward toward the evaporator region within the conduit), while allowing vaporized working fluid to flow in a different direction (e.g., upwardly within the conduit, toward a header). Use of a wick structure may also, or alternatively, facilitate flow of condensed liquid working fluid in a same direction as that of the vaporized working fluid (e.g., vertically upward, vertically downward, and/or laterally) along one or more portions of the 3D vapor chamber (e.g., within the conduit, within the lower body portion, within the header, or other locations within the 3D vapor chamber). The wick structures may help to separate the liquid working fluid from the vaporized working fluid, such that flows of liquid working fluid move separately from flows of vaporized working fluid. The wick structures may also help to block a flow of vaporized working fluid in one more directions. In some examples, the liquid working fluid may be sucked into, or otherwise pulled into, the material of one of the wick structures (e.g., via the capillary action of the wick structure, and/or the positioning of the wick structure), creating a better overall vapor flow within the 3D vapor chamber, and thereby increasing the performance of 3D vapor chamber. Additionally, and as illustrated in FIG. 6, in some examples only a single wick structure may be utilized within one of the conduits (e.g., within a rear conduit 290), although in other examples more than one conduit may include a wick structure extending therein, or the 3D vapor chamber may only include a wick structure or structures beneath the conduits, and/or within the header.

The 3D vapor chambers described herein may include, for example, better liquid management, reduced charge, and improved liquid return, as compared with other heat exchange devices, such as the heat pipe 10 or the vapor chamber 24 of FIGS. 1 and 2. The 3D vapor chambers may also achieve higher heat capacities (e.g., with lower thermal resistance). Such higher capacities may allow for use of a wick material (such as powder) that may have lower permeability and/or capillary pressure (such as finer, more dense, or different morphology powder), but can offer better heat transfer, thus improving the overall thermal resistance of the unit. Additionally, the wick structure or structures do not necessarily need to be extended as far into an adiabatic region or condenser region, where they typically might be required to shield the liquid from the vapor as the liquid is returned to the evaporator. The condenser resistance may also be reduced due to better liquid drainage and the ability to remove the wick structure from the condenser region (e.g., removed entirely). With reduced amount of wick structure and better liquid management, the liquid weight may be reduced. Further, this may reduce the potential for freezing issues that could damage the vapor chamber.

The 3D vapor chambers described herein may further be modified, and/or may include additional features, or variations other than that illustrated. For example, the liquid reservoirs (e.g., any of the liquid reservoirs described herein) may include one or more screens to act as filler material. The screens may be sized, shaped, and/or positioned to only permit working fluid, or certain droplets or streams of working fluid, to move through the screens.

Additionally, any of the conduits, headers, and/or any other passages of the 3D vapor chambers described herein may be sized for sufficient vapor velocity (or dynamic pressure) to entrain liquid droplets and push the liquid droplets away from certain regions to reduce liquid film, flooding, and/or storage in the evaporator, condenser, or any other region of the 3D vapor chamber. This may be of particular importance, for example, where the vapor is flowing horizontally without the aid of, or upwards against, a gravitational force.

Example of General Flow and Movement of Working Fluid in a 3D Vapor Chamber

As described above, a 3D vapor chamber may include structures that facilitate a flow of working fluid in multiple directions. The working fluid may be in condensed, liquid form or evaporated, vaporized form. In some examples, the working fluid may move vertically and/or horizontally, through various conduits, headers, and/or other structures within the 3D vapor chamber.

FIG. 7 schematically illustrates one example of a flow and movement of working fluid through a 3D vapor chamber 306. Similar to the 3D vapor chambers 86, 210 described above, the 3D vapor chamber 306 includes a lower body 310 defining a recessed well 314, an evaporator region 318 (e.g., formed as part of the recessed well 314), and at least one liquid reservoir 322. In other examples the lower body 310 does not include a recessed well 314. The 3D vapor chamber further includes at least one header 326, and conduits 330 that extend (e.g., vertically) between the lower body 310 and the header 326. The 3D vapor chamber 306 also includes a condenser region 334 located above the evaporator region 318. The condenser region 334 includes, for example, stacks of air-cooled fins positioned between the conduits 330. FIG. 7 illustrates in further detail, via sets of arrows, how the working fluid may move through the 3D vapor chamber 306.

Note for example how the working fluid moves vertically upwardly through the conduits 330 directly above and to the right of the evaporator region 318, and how the working fluid then flows mostly to the left within the header 326 (e.g., to a front side of the 3D vapor chamber 306 where cool air is entering and moving across the air-cooled fins of the condenser region 334). Condensed working fluid returns down to the liquid reservoir 322, where the working fluid then eventually re-enters the recessed well 314. In at least one conduit 330, vaporized working fluid may flow up, while condensed, liquid working fluid may flow down, through the same conduit. In some examples, the vaporized and liquid working fluid may flow in the same direction (e.g., in the majority, or vast majority, of the conduits 330).

The 3D vapor chamber 306 may include any of the features of the 3D vapor chambers described herein, such as the 3D vapor chambers 68, 86, or 210 (e.g., at least one wick structure, and/or at least one boundary wall, and/or a particular number and arrangement of liquid reservoirs and conduits). Accordingly, FIG. 7 represents just one example of a flow of working fluid through a 3D vapor chamber. Similar flows may also be found in the 3D vapor chambers 68, 86, or 210 described above, or in any other 3D vapor chambers described herein.

Example Prototype of a 3D Vapor Chamber

FIG. 8 illustrates a physical, working prototype example of a 3D vapor chamber 338 that was created and tested. The vapor chamber 338 includes at least some of the features described above from one or more of the schematic 3D vapor chambers (e.g., the 3D vapor chamber 68, 86, 210, and/or 306). For example, as seen in FIG. 8, the 3D vapor chamber 338 includes a lower body 342 (e.g., defining a recessed well with an evaporator region, and at least one liquid reservoir). The 3D vapor chamber 338 further includes at least one header 346, and conduits 350 (e.g., flat conduits) that extend vertically between the lower body 342 and the header 346. The 3D vapor chamber 338 also includes a condenser region 354 located above the evaporator region. The condenser region 354 includes stacks of air-cooled fins 358 positioned between the conduits 350.

The 3D vapor chamber 338 (or any of the 3D vapor chambers described herein) may come in any of various sizes, depending upon a desired application, and/or a desired thermal performance. As seen in FIG. 8, in some examples the 3D vapor chamber 86 may have an overall height H, an overall length L, and an overall width W. The values for the height H, the length L, and the width W may vary, depending upon a desired application for the 3D vapor chamber, and depending for example upon the size of the heat source that is coupled to the 3D vapor chamber, and/or an amount of heat that is to be removed.

Further Examples of Conduits for a 3D Vapor Chamber

As described above, the conduits of a 3D vapor chamber may have any of a number of shapes and sizes, including flattened shapes. The conduits may not only provide pathways for the working fluid, but may also provide structural stability and support for the overall 3D vapor chamber, extending for example between a lower body and/or liquid reservoir, and a header, and/or supporting a plurality of air-cooled fins.

With reference to FIG. 9A, in some examples one or more of the conduits (e.g., the conduits 178, 290, 330, 350 described above) may be a flat conduit, having a non-circular cross section, and having for example one or more flat, planar side surfaces 360. This is in contrast to cylindrical, or rounded tubular conduits. In some examples, and as seen in FIG. 9A, the flat conduit may include at least one support structure 361 (e.g., an insert and/or a rib) that provides added structural support to the conduit. These flat conduits may facilitate movement of the working fluid as described above, and may provide structural stability to the overall 3D vapor chamber (e.g., holding up the header, and/or providing structural stability at the air-cooled fins).

Additionally, the flat conduits may be aligned to facilitate a flow of air through a condenser region. For example, the flat, planar side surfaces 360 of the conduits may be aligned along a direction of air movement through the 3D vapor chamber. In some examples, use of the flat conduits may facilitate a greater flow of air than with rounded (e.g., cylindrical) conduits.

FIG. 9B again schematically illustrates the 3D vapor chamber 86 (from FIG. 5), from a front view, showing its flat conduits 178, and the header 182 above. In contrast, FIG. 9C schematically illustrates an example of a different 3D vapor chamber 86′ having larger, tubular conduits 178′, and no header. The 3D vapor chamber 86, with its flat conduits 178, provides greater room and space for air to flow through the air-cooled fins 206. In some examples, the flat conduits 178 may be aligned with and along the airflow (e.g., an airflow extending from left to right in FIG. 9B) to facilitate movement of the air across the condenser region.

Further Examples of Headers for a 3D Vapor Chamber

As described above, a 3D vapor chamber may include a header, where working fluid (e.g., vaporized working fluid) is delivered during use via conduits. The header may take on any number of sizes, shapes, and forms, and may include one or more structures to direct and/or control movement of working fluid. The header may additionally, or alternatively, include one or more structures (e.g., posts) that provide structural stability to the header and/or to the overall 3D vapor chamber.

For example, FIG. 10A illustrates the prototype header 346 seen from FIG. 8, and FIG. 10B provides a further schematic illustration of the header 346, showing the conduits 350 that extend to and connect with the header 346. As seen in FIGS. 10A and 10B, the header 346 may include a geometric feature (e.g., protrusion, angled wall, etc.) that helps to direct a continuous flow of working fluid within the header 346, and that inhibits “dead zones” where the working fluid might otherwise condense and accumulate (e.g., as droplets) within the header 346.

In the illustrated example, the geometric feature includes triangular protrusions 362, each formed by interior perimeter walls of 366 of the header 346, for example along a bottom of the header 346. These triangular protrusions 362 may help to guide a flow of working fluid into and/or out of the conduits 350. These geometric features may also provide added structural stability to the header 346. Other protrusions 362 may have other shapes (e.g., rectangular or square shapes, or trapezoidal shapes, or curved shapes with convex and/or concave surfaces). Similar geometric features may also be included on any of the other 3D vapor chambers described herein (e.g., the 3D vapor chamber 68, 86, 210, 306, etc.). Other examples do not include this geometric feature.

With continued reference to FIG. 10B, and as described above, the conduits 350 themselves that extend to the header 346 may also be flat in shape, and have a cross-sectional shape that facilitates flow (e.g., laminar flow) of working fluid through the 3D vapor chamber (e.g., laterally through the air-cooled fins). In the illustrated example, the conduits 350 can be seen to have elongate, rectangular (or oval) cross-sectional shapes, with the flat planar side surfaces 360 described above, and are aligned individually (and for example with one another) to facilitate the flow of air through the condenser.

With reference to FIGS. 10A and 10B, in some examples one or more of the 3D vapor chambers described herein may include one or more posts 370 that provide structural support to the 3D header and/or rest of the 3D vapor chamber (e.g., to the prevent the header from collapsing or otherwise deforming when subjected to a vacuum). In the illustrated example, the posts 370 are integrally formed as part of the header 346, and are spread out and spaced apart from one another within the header 346. The posts 370 may extend entirely from a top of the header to a bottom of the header, or may extend partially through the header, and/or may extend below the header (e.g., into the condenser region).

The posts 370 may have various shapes and sizes. As illustrated in FIGS. 10A and 10B, in some examples the posts 370 may have cross-sectional shapes that facilitate flow of the working fluid around the posts 370, and inhibit or prevent the working fluid from accumulating (e.g., stalling behind or otherwise adjacent to one of the posts 370) within the header 346. In the illustrated example, the posts 370 have streamlined, non-circular (e.g., lemon-shaped) cross-sectional shapes, that facilitate a flow of the working fluid along a lateral direction (left to right or right to left) within the header in FIG. 10B.

The posts 370 may also reduce turbulence, and reduce stalling of flow on a back side of the posts 370, thereby inhibiting or preventing accumulation of liquid on the posts 370. As seen in FIG. 10B, the posts 370 may be aligned with one another (e.g., in rows) to further facilitate the flow of working fluid.

Other examples include posts 370 having different cross-sectional shapes and sizes and positions than that illustrated (e.g., circular shaped oval shaped rectangular shaped, teardrop-shaped or other streamlined shaped, etc.). For example, FIG. 10C illustrates an alternative header 346′ in which the posts 370′ have a more circular cross-sectional shape.

With continued reference to FIG. 10C, in some examples a header (e.g., the header 346) includes one or more fill tube holes 374. A fill tube(s) may be coupled to this fill tube hole(s) 374. Liquid may be added, and air removed, through the use of the fill tube and/or the fill tube hole 368. In other examples, a fill tube hole 368 may be provided elsewhere on the header 346, and/or elsewhere on the 3D vapor chamber 338 in general.

FIG. 10D illustrates yet another alternative header 346″. The header 346″ may include a closed off space 376. The closed off space 376 may be formed, for example, from solid material (e.g., metal), and/or is otherwise formed such that there is no internal vapor space present. The closed off space 376 may be included, for example, if the flow of working fluid in the header 346″ is not intended to extend laterally (i.e., to the right or left in FIG. 10D) across the entirety of the header 346″, or at least across the closed off space 376. Rather, the flow of working fluid extends either laterally to the left, or laterally to the right, once reaching the header 346″, and therefore never crosses the closed off space 376. In some examples, a 3D vapor chamber may also include one or more venting channels (e.g., on one or more sides of the closed off space 376), to allow air to be removed when processing or pulling vacuum on the 3D vapor chamber. Other examples do not include the closed off space 376 and/or venting channels.

FIGS. 10A-10D represent just a few examples of a header for a 3D vapor chamber (e.g., for the 3D vapor chamber 86, 210, 306, 338, etc.). Headers similar to the headers 346, 346′, and 346″ however may be used in conjunction with any of the 3D vapor chambers described herein.

Sheets/Collars for a 3D Vapor Chamber

As described above, a 3D vapor chamber may include one or more conduits to facilitate movement of working fluid within the 3D vapor chamber. The 3D vapor chamber may also include a lower body and/or a header. Accordingly, some 3D vapor chambers may include one or more structures that facilitate movement of working fluid from one component (e.g., the header) to the next (e.g., the conduit) within the 3D vapor chamber.

For example, and with reference to FIG. 11, in some examples a 3D vapor chamber may include one or more conduits (e.g., such as the conduits 178, 290, 330, 350, etc.) that are inserted into a stamped (or machined or 3D printed with additive manufacturing) sheet. A collar in the sheet acts as a well to drain liquid (e.g., condensed working fluid) into the conduit. In the illustrated example, the conduit 178 (e.g., from the 3D vapor chamber 86 in FIG. 5) extends between the lower body 102 and the header 182. A portion (e.g., the header lower wall 190 of FIG. 3) of the header 182 may include a sheet 378. A portion of the sheet 378 is stamped, or otherwise deformed, forming an opening allowing an upper portion of the conduit 178 to extend into the opening. As seen in FIG. 11, an upper end of the conduit 178 is positioned below a portion of the sheet 378. The sheet 378 is shaped or sloped (e.g., bent with a curve) at the opening, forming a collar 382, which acts as a well and facilitates drainage of liquid into the conduit 178. Condensed working fluid that is forming, accumulating, and/or moving along the sheet 378 slides (e.g., via assistance from gravity) along the curved collar 382, and drops into the upper end of the conduit 178.

Additionally, or alternatively, a portion of the lower body 102 (e.g., the first upper reservoir wall 138 described above) may include a sheet 386 (e.g., lower plate) that is similarly deformed, forming an opening to receive a bottom of the conduit 178, and forming a collar 390. In some examples, the collars 382, 390 aid in forming a trough for a braze material when joining the conduit 178 to the sheets 378, 386. Other examples do not include the sheets 378, 386, or the collars 382, 390. Additionally, in some examples the sheet 378 and/or the sheet 386 may be shaped and/or machined with slopes or drainage paths that help the liquid drain to the collars 382, 390 and/or the conduits 178.

FIG. 11 represents just one example of a set of sheets and collars that may be used to facilitate flow of liquid within a 3D vapor chamber. Similar sheets and collars may also be used in conjunction with any of the vapor chambers described herein.

Reinforcment Plate for a 3D Vapor Chamber

As described above, a 3D vapor chamber may include one or more conduits to facilitate movement of working fluid through the 3D vapor chamber. Accordingly, the 3D vapor chamber may extend vertically, and may benefit from the use of one or more reinforcement elements to provide added structural support.

For example, and with reference to FIG. 12, in some examples a 3D vapor chamber may include a reinforcement plate 392. In the illustrated example, the reinforcement plate 392 is positioned between the conduits (e.g., conduits 178 from FIG. 5), and is positioned above (e.g., and in contact with) the lower body 102 and/or the evaporator region (e.g., the evaporator region 90). The reinforcement plate 392 may be formed, for example, from a material having a strength stronger than that of the conduits 178, the lower body 102, the header, and/or any other portion of the vapor chamber. In some examples, the reinforcement plate 392 is inserted between two tube sheets (e.g., the sheets 378, 386), prior to joining or attaching the risers (e.g., the conduits 178, 290, 330, 350, etc.). Other examples do not include a reinforcement plate 392, or include a reinforcement plate 392 that is not stronger than that of other parts of the vapor chamber, or include a reinforcement plate 392 having a different profile and/or positioning than that illustrated.

FIG. 12 represents just one example of a reinforcement plate 392 that may be used with a 3D vapor chamber. Similar reinforcement plates may also be used in conjunction with any of the 3D vapor chambers described ambers described herein.

Structural Features for Evaporator Region and/or Lower Body

As described above, thermal devices such as heat pipes and vapor chambers (e.g., those schematically illustrated in FIGS. 1-7, and as shown in prototype in FIG. 8) may include one or more evaporator regions that receive heat from a heat source. Additionally, some thermal devices (e.g., the 3D vapor chambers described above) may include a lower body that includes the evaporator region. It is important that the thermal devices not only effectively transmit heat, but also be structurally sound, particularly in regions such as the evaporator region and/or lower body of the thermal device. For example, evaporator regions are commonly coupled (e.g., with fasteners, welds, adhesive, with clamping, or via other methods) to a heat source (e.g., a processor or other electronic device). Accordingly, this coupling of the thermal device to the heat source often creates stresses and forces that act upon the thermal device and more specifically the evaporator region of the thermal device. Therefore, providing added structural features directly to the evaporator region of a thermal device, and/or to a lower body that includes the evaporator region, may alleviate the stresses that naturally occur when a thermal device is coupled to a heat source.

Therefore, in some examples, the evaporator regions and/or lower bodies described herein may include additional structures (e.g., extended surfaces that define posts or ribs, or other enhancements (e.g., rounded edges, fillets, etc.)) to reduce thermal resistance, increase a capacity of the thermal device, and/or provide added structural stability. Adding these additional structures may, in some examples, allow the evaporator wall itself (e.g., the lower well wall and/or lowermost wall that is in direct contact with the heat source along the evaporator region) to be machined thinner, thus providing even more benefit to the evaporator thermal resistance, Additionally, use of evaporator regions and/or lower bodies with additional structures (such as extended surfaces) may result in higher capacities for the overall unit. Such higher capacities may allow for use of a wick material (such as powder) that may have lower permeability and/or capillary pressure (such as finer, more dense, or different morphology powder), but can offer better heat transfer, thus improving the overall thermal resistance of the unit.

FIGS. 13-25 illustrate various examples of added structures for an evaporator region (e.g., for the evaporator region 12, 26, 54, 70, 90, 226, 318, etc.) and/or for a lower body (e.g., the lower body 102, 214, 310, 342, etc.). Such structures may be machined, formed, and/or attached (e.g., out of base material). In some examples, the structures are covered partially or entirely by one or more wick structures, such as any of the wick structures described herein.

FIGS. 13A, 13B. and 13C illustrate the lower body 342 of the prototype 3D vapor chamber 338 from FIG. 8. As illustrated in these figures, the lower body 342 may include an evaporator region 394 (e.g., formed in a recessed well, similar to the recessed well 110 in the schematic representation of FIG. 5). In the illustrated example, the lower body 342 additionally includes extended surfaces that define posts 398 (similar to the posts 370 described above in the header 346), that are positioned both around the evaporator region 394, and also within the evaporator region 394. Similar to the posts 370, these posts 398 may provide structural stability to the lower body 342 itself and/or the evaporator region 394, especially when the hollow interior of the lower body 342 is subject to a vacuum. In the illustrated example, the posts 398 are formed integrally as part of the lower body 342. In some examples, the posts 398 may extend entirely from a top of the lower body 342 to a bottom of the lower body 342, or only partially through the lower body 342, and/or may extend upwardly out of the lower body 342 (e.g., into the condenser region). In some examples one or more of the posts 398 may be covered partially or entirely by a wick structure. Other thermal devices described herein may similarly include such additional posts. Additionally, the posts 398 may have other shapes and sizes than that illustrated.

With continued reference to FIGS. 13A, 13B, and 13C, the lower body 342 may also, or alternatively, include a screen 400. In the illustrated example, the screen 400 is positioned within a liquid reservoir of the lower body 342 (the liquid reservoir corresponding, for example, to the liquid reservoir 130 seen in the schematic representation in FIG. 5). The screen 400 may be a wire mesh, or other structure, that acts for example as a filler material (e.g., metal) to prevent any liquid within the reservoir from freezing and expanding (e.g., in extreme low temperature environments).

With continued reference to FIGS. 13A, 13B, and 13C, the evaporator region 394 may additionally include a plurality of other extended surfaces 402 (e.g., protruding ribs, beams, and/or the like). The extended surfaces 402 may be integrally formed with the rest of the evaporator region 394, and may for example be made out of metal or other suitable material. As seen in these figures, the extended surfaces 402 may form an overall matrix, or web, of protruding surfaces that not only facilitate movement of heat in the evaporator region 396, but also enhance the overall strength of the evaporator region 394. One or more of the extended surfaces 402 may be covered partially or entirely by a wick structure.

FIGS. 14-16 schematically illustrate additional examples of structures for an evaporator region of a thermal device, as viewed from the side. For example, and with reference to FIG. 14, in the illustrated example an evaporator region may include a lower wall 404 (e.g., forming part of the lower well wall 114 or 230 described above), and a wick structure 406 (e.g., a flat powder wick structure) positioned above (e.g., directly above and in contact with) the lower wall 404. The wick structure 406 may form at least part of the wick structure 166 or the wick structure 246 described above.

With reference to FIG. 15, in some examples the evaporator region includes a lower wall 404, and a wick structure having a generally flat portion 410, with powder ribs 414 that extend vertically upwardly from the generally flat portion 410 and the lower wall 404.

In yet other examples, and as seen in FIG. 16, the evaporator region includes a lower wall 404 having extended surfaces 418 (e.g., ribs, or fins) that extend upwardly from the lower wall 404 and are at least partially covered by (e.g., surrounded by) the powder ribs 414 of the wick structure.

In some examples, a vertical thickness of the wick structure material (e.g., of the powder rib 414) may be increased, or larger, above the extended surface 418 than at other locations, particularly if this area is a region of high flow in the thermal device. Overall, the vertical thickness of the wick structure material in the powder ribs 414 may be chosen for example based on a desired flow, or anticipated flow, of liquid across the evaporator region.

FIGS. 17-19 illustrate yet further examples of structures for evaporator regions of a thermal device, as viewed from above. With reference to FIG. 17, for example, an evaporator region may include extended surfaces 418 (e.g., ribs) that extend upwardly from a lower wall (in a direction out of the page in FIG. 17), and are generally planar (e.g., thin, and elongated). Rounded posts 422 (e.g., similar to the posts 398) may extend upwardly from the extended surfaces 418 (e.g., out of the page in FIG. 17) at spaced apart locations, and/or may be positioned between and act to separate the extended surfaces 418 from one another. The rounded posts 422 may be circular in cross-section, although other examples have other shapes (e.g., oval shapes). In contrast, the extended surfaces 418 may be rectangular in cross-section. In some examples, the rounded posts 422 may have diameters, or thicknesses, that are smaller than that of the extended surfaces 418. The extended surfaces 418 and/or the posts 422 may be at least partially covered by (e.g., surrounded by) a wick structure, such as the wick structure 406.

With reference to FIG. 18, in some examples the evaporator region includes additional extended surfaces, in the form of rectangular posts 426, that extend upwardly from the extended surfaces 418, and/or separate the extended surfaces 418 from one another. The rectangular posts 426 have a thickness, as seen in FIG. 18, that is equivalent to the thickness of the planar extended surfaces 418 themselves, although in other examples the thicknesses vary. The planar extended surfaces 418 and the rectangular posts 426 may be at least partially covered by a wick structure.

With reference to FIG. 19, in some examples an evaporator region may include extended surfaces 418 that are arranged in a grid pattern, as seen from above (similar to the arrangement of extended surfaces 402 in FIGS. 13A-13C). The grid pattern may include a series of extended surfaces 418 that form squares, or rectangles, with openings therein. In some examples, the grid pattern includes a parallel arrangement of extended surfaces 418 or other structures, whereas in other examples the pattern may not be parallel, at least in one or more regions. As illustrated in FIG. 19, the posts (e.g., the rounded posts 422 or the rectangular posts 426) may be positioned at intersections of the extended surfaces 418 (e.g., at the four corners of one of the squares or rectangles within the grid structure). A wick structure, such as the wick structure 406, may cover at least a portion of the extended surfaces 418 and the posts 422.

The grid patterns and layout may vary from that illustrated. In some examples, the layout of extended surfaces may include parallel planar extended surfaces, extended surfaces laid out in a square or rectangular grid, or any other grid pattern such as hexagonal, circular, triangular, rhombic, other quadrilateral shapes, or any other shape or pattern. Additionally, while rounded and rectangular posts 422, 426 are illustrated, the posts may have other shapes, such as oval, square, or any other shape.

With reference to FIG. 20, in some examples an evaporator region includes extended surfaces 418 that extend vertically upwardly a height H, and extend parallel to one another at a pitch distance “PD.” In other examples the extended surfaces 418 do not extend parallel to one another, and/or are spaced differently. With continued reference to FIG. 20, in the illustrated example the posts 422 (or 426, or other posts) extend vertically upwardly from the extended surface 418. Each of the posts 422 has a width W1 that is equal to or smaller than a width W2 of the extended surface 418, although other examples include different widths than that illustrated.

A wick structure (e.g., the wick structure 406) may be positioned along one or more sides of the posts 422 and the extended surfaces 418. In the illustrated example, enough wick structure 406 is positioned on the sides of the extended surfaces 418 to maintain wetting and connectivity to roots of the extended surfaces 418 near the lower wall 404. The wick structure 406 has a first thickness T1 near a top of the wick structure 406 (e.g., at the posts 422), and has a smaller (or equal or larger) thickness T2 in the roots. Enhancements 430 (e.g., fillets, or formations of other curved surfaces) may be machined or otherwise formed in the wick structure 406 where the wick structure 406 is sometimes the thinnest near the root. The amount of wick structure 406 to either side of each extended surface 418 maintains good wetting to the enhancement 430 while shortening a conduction length through the wick structure 406.

To form the arrangement seen in FIG. 20, a mandrel (e.g., a tapered mandrel) may be inserted down vertically between the two illustrated extended surfaces 418. The mandrel may have square edges, rounded edges, a semicircular shape, a triangular shape, or any other shape. When the mandrel is removed, a gap G is formed between the wick structure portions at the top of the wick structure 406. This region between the wick structure portions, and between the extended surfaces 418, is a pocket, and may receive for example a portion of the liquid working fluid during use of the 3D vapor chamber.

In some examples, the extended surfaces 418 do not need to be uniform thickness with increasing height. The extended surfaces 418 may taper, come to a point, be rounded, or have any other fin shape. The extended surfaces 418 themselves may also have an enhancement 434 (e.g., fillet) machined, or otherwise formed. As seen in FIG. 20, in the illustrated example the wick structure 406 curves up slightly at a central location 438 between the two extended surfaces 418 at the roots of the extended surfaces 418. The wick structure 406 may be thinner here, due to this curvature, to facilitate heat transfer in this region. In other examples, the wick structure 406 may maintain a more constant thickness at this location, or may be thicker.

Various factors may be considered when forming the structure seen in FIG. 20. For example, minimum thickness of the mandrel, minimum thickness of the wick structure 406, minimum thickness of extended surfaces 418, and spacing of extended surfaces 418 may all be considered in formation of the structure. Additionally, for areas where nucleate boiling may occur in the evaporator region, it may be beneficial for the lower regions of the wick structure 406 to have more sharpened corners (e.g., removal of fillets), rather than the curved corners as seen in FIG. 20. The shapes and sizes of the surfaces may be altered, depending for example on the type of heat transfer anticipated at the evaporator region.

With reference to FIGS. 21-23, in some examples an evaporator region includes extended surfaces 418 (e.g., with posts 422) in square patterns. The wick structure 406 may be positioned at least partially over the extended surfaces 418 and/or the posts 422. Additional wick structure may be present on top of the extended surfaces 418 to allow horizontal flow of liquid into a middle of the evaporator region, where it may then feed down into individual pockets 440 between the extended surfaces 418 (e.g., each pocket 440 and its surrounding extended surfaces 418 defining a “cell” of the grid structure).

With reference to FIGS. 24A, 24B, and 25, in some examples, the extended surfaces 418 may end just outside the evaporator region, or at the edge of the evaporator region (e.g., evaporator region 226), where the extended surfaces 418 either form a wall or are located near a wall (e.g., the boundary wall 146, 162, 262 described above, or another wall). This arrangement may allow for excess liquid to collect, and prevent flooding of liquid into the evaporator region 226. The wick structure (e.g., wick structure 246) may include large wick channels/ribs that run into the evaporator region to help carry liquid while not taking up too much space in the area around the evaporator region.

As illustrated in FIGS. 24A and 24B, a moat region 442 may be provided outside of the extended surfaces 418. The moat region 442 may be adjacent to, or surround, the evaporator region 226. The moat region 442 may be located lower, for example, than the liquid reservoir (e.g., liquid reservoir 130), and may be separated from the liquid reservoir 130 by a wall (e.g., the wall 146). Liquid located in the liquid reservoir 130 may transfer to the moat region 442 (e.g., over the wall 146 via the peripheral portion 282 of the wick structure 246), and liquid in the moat region 442 may transfer to the evaporator region 226 (e.g., over the outside extended surface 418), due for example to gravitational forces that force the liquid pressure to be higher than the vapor pressure at the lowest point in the liquid level. This may have a slight benefit to helping to feed liquid to the evaporator region 226 if there is excess liquid flooding over a wick that spills into this region. In some examples, the extended surfaces 418 described above also provide structural benefit, and/or can be tied into side walls of the 3D vapor chamber. The extended surfaces 418 may also, or alternatively, stiffen up the area where there is contact with the heat source.

In some examples, the wick structure provided in the region of the boundary wall may have varying thicknesses, to facilitate flow. For example, the wick structure may be thinner in some regions (e.g., alongside the boundary wall 146) due to spatial constraints, the need for vapor to also travel in this region, or to induce a higher liquid pressure drop to reduce liquid seepage out of the wick structure on the downstream side. The wick structure may be thicker in other regions (e.g., to slow a flow, or to provide sufficient wicking for area of high flow).

With reference to FIG. 24B, in some examples the wick structure (e.g., the wick structure 246) may include a first peripheral portion 282a, and also a second peripheral portion 282b. The second peripheral portion 282b may be spaced farther away from the evaporator region 226 than the peripheral portion 282a. In the illustrated example, the first peripheral portion 282a and the second peripheral portion 282b are sized and shaped such that a two-stage reservoir (with high pressure 130a and low pressure 130b regions) is formed. Vapor is allowed to travel over the wall 146 and the first peripheral portion 282a (from right to left in FIG. 24B), but any droplets that may drip down from the conduits may be collected in the high-pressure reservoir 130a. The high-pressure reservoir 130a and the low-pressure reservoir 130b may still exchange liquid, however, due to the presence of the powdered peripheral portion 282b that allows liquid to seep through, but blocks the majority of the vapor from making its way to the low-pressure reservoir 130b.

With continued reference to FIGS. 24A, 24B, and 25, the wall formed at least partially around the evaporator region (e.g., the boundary wall 146, 162, 262 or other wall) may have various shapes. For example, as illustrated in FIG. 25, in some examples the wall has a “serpentine” shape, along at least a portion of the wall, that winds back and forth. Such a shape may be beneficial across a range of operating conditions with high heat rates. In other examples, the wall may be straight, or have shapes other than serpentine. As described above, the wall may help to reduce or eliminate flooding of the evaporator region.

Additional Examples of Thermal Devices

Many of the thermal devices described above, and in particular the 3D vapor chambers described above, include the use of a header. However, some 3D vapor chambers may entirely omit the use of a header.

For example, and as illustrated in FIG. 26, in some examples a 3D vapor chamber 446a includes a lower body 450 (e.g., having an evaporator region and/or a liquid reservoir). The 3D vapor chamber 446 also includes one or more conduits 454 that extend in a “loop” away from the lower body 450. In the illustrated example, the conduit 454 includes a first portion 458 that extends away (e.g., at a 90 degree angle) from the lower body 450, a second portion 462 that extends generally parallel to the lower body 450, and a third portion 466 that extends generally parallel to the first portion 458. Other examples include different angles and numbers of portions. The first, second, and third portions 458, 462, 466 form a pathway for working fluid (in vaporized form or liquid form). As with other conduits described herein, the 3D vapor chamber 446 may include a wick structure or structures disposed at least partially within the lower body 450 and/or within one or more of the first, the second, or the third portions 458, 462, 466 of the conduit 454.

FIG. 27 illustrates a further example, in which a 3D vapor chamber 446b includes multiple conduits 454, positioned in a row. FIG. 28 illustrates yet a further example of a 3D vapor chamber 446c, in which the conduits 454 are staggered. FIG. 29 illustrates yet a further example of a 3D vapor chamber 33, in which some of the conduits 454 are arranged within other conduits 454 (e.g., in a space directly between the lower body 450 and the other conduits 454).

Other examples include different combinations and orientations of conduits 454 than that shown. In each of FIGS. 26-29, a condenser region may also be present. For example, a portion of one or more of the conduits 454 themselves may form part of the condenser region. In some examples, the 3D vapor chamber 446a, 446b, 446c, and/or 446d may include one or more air-cooled fins located in proximity to the conduit or conduits 454.

Additionally, and with reference to FIG. 30, in some examples a vapor chamber 470 includes one or more fins 474 that extend from a header (or headers) 478. The fins 474 may extend vertically upwardly, or at different angles, from the header 478. In some examples, the fins 474 extend vertically upwardly from a header upper wall (e.g., the header upper wall 186 seen in FIG. 3). Similar to the air-cooled fins 206 described above, the fins 474 may be spaced apart from one another, and in some examples may be spaced differently from one another at different locations along the vapor chamber 470. Stacks or regions of the fins 474 may have different densities from one another. In some examples, the fins 474 are spaced evenly apart from one another, and extend vertically upward, moving heat vertically away from the header 478. As illustrated in FIG. 30, the vapor chamber 470 may also include components similar to those of the vapor chambers described above, including for example a lower body 482, conduits 486, and air-cooled fins 490.

The thermal devices illustrated in FIGS. 26-30 may include any of the other various features described herein as they relate to a thermal device, including for example conduits, headers, posts, wick structures, reinforcement plates, extended surfaces, or other structures that provide structural stability and/or enhance a flow of heat.

Although various aspects and examples have been described in detail with reference to certain examples illustrated in the drawings, variations and modifications exist within the scope and spirit of one or more independent aspects described and illustrated.

Some of the examples may be further described by reference to the following numbered clauses:

• • 1. A 3D vapor chamber comprising:
    • a lower body defining an evaporator region;
    • a header positioned above the lower body;
    • conduits extending between the lower body and the header;
    • a condenser region; and
    • a working fluid located within at least one of the lower body, the header, or the conduits,
    • wherein the conduits are configured to direct a flow of the working fluid to and from the lower body and the header, wherein a portion of the working fluid is configured to be in vaporized form during use, and another portion of the working fluid is configured to be in liquid form during use, wherein the conduits are arranged such that the vaporized working fluid and the liquid working fluid are configured to flow in a same direction in at least one of the conduits.
  • 2. A 3D vapor chamber comprising:
    • a lower body defining an evaporator region;
    • a header positioned above the lower body;
    • conduits extending between the lower body and the header;
    • a condenser region positioned between the lower body and the header;
    • a working fluid located within at least one of the lower body, the header, or the conduits; and
    • a wick structure located within the lower body, wherein the wick structure is positioned in the lower body so as to block movement of a vaporized portion of the working fluid, and to force the vaporized portion of the working fluid to enter one or more of the conduits, and to flow up into the upper header before flowing back down through one or more of the conduits.
  • 3. A 3D vapor chamber comprising:
    • a lower body defining a recessed well, wherein the recessed well defines an evaporator region;
    • a header positioned above the lower body;
    • conduits extending between the lower body and the header;
    • a condenser region positioned between the lower body and the header;
    • a working fluid located within at least one of the lower body, the header, or the conduits; and
    • a boundary wall located within the lower body, wherein the boundary wall is configured to hold back a portion of the working fluid from entering the recessed well.
  • 4. A 3D vapor chamber comprising:
    • a lower body defining an evaporator region;
    • a header positioned above the lower body;
    • conduits extending between the lower body and the header, wherein the conduits are configured to direct a flow of working fluid between the lower body and the header; and
    • a condenser region positioned between the lower body and the header;
    • wherein the conduits include a first conduit having a first width, and a second conduit having a second width different than the first width.
  • 5. A 3D vapor chamber comprising:
    • a lower body defining an evaporator region;
    • a header positioned above the lower body;
    • conduits extending between the lower body and the header, wherein the conduits are configured to direct a flow of working fluid between the lower body and the header; and
    • a condenser region positioned between the lower body and the header;
    • wherein the conduits are sized and shaped such that a different aggregate cross-sectional area of the conduits exists for a vapor flow of the working fluid moving upwardly than for a return vapor flow of the working fluid moving downwardly.
  • 6. A 3D vapor chamber comprising:
    • a lower body defining an evaporator region;
    • a header positioned above the lower body;
    • conduits extending between the lower body and the header, wherein the conduits are configured to direct a flow of working fluid between the lower body and the header; and
    • a condenser region positioned between the lower body and the header, wherein the condenser includes air-cooled fins arranged in stacks, wherein a density of the air-cooled fins within one of the stacks varies within the stack.
  • 7. A 3D vapor chamber comprising:
    • a lower body defining an evaporator region;
    • a header positioned above the lower body;
    • conduits extending between the lower body and the header, wherein the conduits are configured to direct a flow of working fluid between the lower body and the header;
    • a condenser region positioned between the lower body and the header; and
    • a wick structure located within the lower body;
    • wherein one or more of the conduits is in direct contact with the wick structure.
  • 8. A 3D vapor chamber comprising:
    • a lower body defining an evaporator region;
    • a header positioned above the lower body;
    • a condenser region positioned between the lower body and the header; and posts in the header, wherein each of the posts has a streamlined cross-sectional shape.
  • 9. A 3D vapor chamber comprising:
    • a lower body defining an evaporator region;
    • a header positioned above the lower body;
    • conduits extending between the lower body and the header, wherein the conduits are configured to direct a flow of working fluid between the lower body and the header; and
    • a condenser region positioned between the lower body and the header, wherein the condenser includes air-cooled fins arranged in stacks, wherein a density of the air-cooled fins in one stack is different than a density of air-cooled fins in a different stack.
  • 10. A 3D vapor chamber comprising:
    • a lower body defining an evaporator region;
    • a header positioned above the lower body;
    • conduits extending between the lower body and the header, wherein the conduits are configured to direct a flow of working fluid between the lower body and the header;
    • a condenser region positioned between the lower body and the header; and
    • a wick structure that extends at least partially within one or more of the conduits or the header.
  • 11. A 3D vapor chamber comprising:
    • a lower body defining an evaporator region;
    • a header positioned above the lower body;
    • conduits extending between the lower body and the header, wherein the conduits are configured to direct a flow of working fluid between the lower body and the header; and
    • a condenser region positioned between the lower body and the header;
    • wherein the evaporator region includes a lower wall, and fins that extend upwardly from the lower wall, wherein the evaporator region further includes a wick structure that extends at least partially over the fins.
  • 12. A 3D vapor chamber comprising:
    • a lower body defining an evaporator region;
    • a header positioned above the lower body;
    • conduits extending between the lower body and the header, wherein the conduits are configured to direct a flow of working fluid between the lower body and the header; and
    • a condenser region positioned between the lower body and the header;
    • wherein the evaporator region includes a parallel arrangement, grid, and/or any other regular or irregular pattern of fins, posts, and pockets.
  • 13. A 3D vapor chamber comprising:
    • a lower body defining an evaporator region;
    • a conduit extending away from the lower body and looping back to the lower body; and
    • a working fluid located within at least one of the lower body or the conduit,
    • wherein the conduit is configured to direct a flow of the working fluid to and from the lower body, wherein a portion of the working fluid is configured to be in vaporized form during use, and another portion of the working fluid is configured to be in liquid form during use.
  • 14. A thermal device comprising:
    • an evaporator region having a plurality of extended surfaces that define a matrix, wherein the extended surfaces are configured to provide structural support for the evaporator region; and
    • a wick structure that covers at least a portion of the extended surfaces, wherein the wick structure includes powder ribs.
  • 15. A thermal device comprising:
    • an evaporator region;
    • a liquid reservoir located adjacent the evaporator region; and a screen positioned in the liquid reservoir.
  • 16. A 3D vapor chamber comprising:
    • a lower body defining an evaporator region;
    • a header positioned above the lower body;
    • conduits extending between the lower body and the header;
    • a condenser region; and
    • a working fluid located within at least one of the lower body, the header, or the conduits,
    • wherein the conduits are configured to direct a flow of the working fluid to and from the lower body and the header, wherein a portion of the working fluid is configured to be in vaporized form during use, and another portion of the working fluid is configured to be in liquid form during use, wherein the conduits are arranged such that the vaporized working fluid and the liquid working fluid are configured to flow in a same direction in none, some, a majority, or all of the conduits.

Various features and advantages of the disclosure are set forth in the following claims.

Claims

1. A 3D vapor chamber comprising: a lower body defining an evaporator region;a header positioned above the lower body;conduits extending between the lower body and the header;a condenser region; anda working fluid located within at least one of the lower body, the header, or the conduits,wherein the conduits are configured to direct a flow of the working fluid to and from the lower body and the header, wherein a portion of the working fluid is configured to be in vaporized form during use, and another portion of the working fluid is configured to be in liquid form during use, wherein the conduits are arranged such that the vaporized working fluid and the liquid working fluid are configured to flow in a same direction in at least one of the conduits.

2. The 3D vapor chamber of claim 1, wherein the vaporized working fluid and the liquid working fluid are configured to flow in a same direction in the condenser region.

3. The 3D vapor chamber of claim 1, wherein the lower body defines a hollow interior and a recessed well, wherein the recessed well defines at least a portion of the evaporator region.

4. The 3D vapor chamber of claim 3, wherein the lower body defines a liquid reservoir configured to receive the liquid working fluid from the condenser region and to direct the liquid working fluid toward the recessed well, wherein the liquid reservoir includes a lower reservoir wall, an upper reservoir wall, a side reservoir wall that extends from the lower reservoir wall to the upper reservoir wall, and a boundary wall that extends upwardly from the lower reservoir wall and terminates before reaching the upper reservoir wall.

5. The 3D vapor chamber of claim 4, wherein the boundary wall has a serpentine shape.

6. The 3D vapor chamber of claim 4, further comprising a wick structure that extends into the recessed well, wherein the wick structure includes a peripheral portion that extends upwardly out of the recessed well and wraps up and over the boundary wall.

7. The 3D vapor chamber of claim 6, wherein the peripheral portion physically contacts the upper reservoir wall, and also physically contacts the first lower reservoir wall, and wherein the peripheral portion is configured to inhibit the vaporized working fluid from passing therethrough.

8. The 3D vapor chamber of claim 6, wherein the at least one of the conduits is a first conduit, wherein the wick structure is a first wick structure, wherein the 3D vapor chamber further includes a second conduit and a second wick structure extending vertically within the second conduit, wherein the second wick structure is configured to direct the liquid working fluid toward the first wick structure.

9. The 3D vapor chamber of claim 8, wherein the header includes posts configured to provide structural support for the header, wherein the posts have non-circular cross-sectional shapes to facilitate a flow of the working fluid through the header along a lateral direction.

10. The 3D vapor chamber of claim 1, wherein the conduits include a first conduit having a first width, and a second conduit having a second width different than the first width, wherein the condenser includes air-cooled fins arranged in stacks, and wherein a density of the air-cooled fins in one stack is different than a density of air-cooled fins in a different stack.

11. The 3D vapor chamber of claim 1, wherein the evaporator region includes a lower wall and extended surfaces that extend upwardly from the lower wall, wherein the evaporator region further includes a wick structure that extends at least partially over the extended surfaces.

12. The 3D vapor chamber of claim 11, wherein the extended surfaces are fins that define a matrix in the evaporator region, wherein the extended surfaces are configured to provide structural support for the evaporator region.

13. The 3D vapor chamber of claim 12, wherein the evaporator region further includes posts extending vertically upwardly from the fins, wherein the wick structure further extends over the posts.

14. A 3D vapor chamber comprising: a lower body defining an evaporator region;a header positioned above the lower body;conduits extending between the lower body and the header, wherein the conduits are configured to direct a flow of working fluid between the lower body and the header; anda condenser region positioned between the lower body and the header;wherein the evaporator region includes a lower wall, and extended surfaces that extend upwardly from the lower wall, wherein the evaporator region further includes a wick structure that extends at least partially over the extended surfaces.

15. The 3D vapor chamber of claim 14, wherein the extended surfaces are fins that define a matrix in the evaporator region, wherein the extended surfaces are configured to provide structural support for the evaporator region.

16. The 3D vapor chamber of claim 15, wherein the evaporator region further includes posts extending vertically upwardly from the fins, wherein the wick structure further extends over the posts.

17. The 3D vapor chamber of claim 16, wherein each of the extended surfaces includes a root located where the extended surface rises upwardly from the lower wall, wherein the wick structure has a first thickness along one of the fins, and a second thickness at one of the roots, wherein the first thickness is greater than the second thickness.

18. The 3D vapor chamber of claim 16, wherein each of the fins has a first width and each of the posts has a second width, wherein the first width is greater than the second width.

19. The 3D vapor chamber of claim 14, wherein the wick structure includes powder ribs.

20. The 3D vapor chamber of claim 14, wherein the wick structure is positioned in the lower body so as to block movement of a vaporized portion of the working fluid, and to force the vaporized portion of the working fluid to enter one or more of the conduits, and to flow up into the header before flowing back down through one or more of the conduits.