VARIABLE DIMENSION HEAT PIPE

Abstract

A heat pipe, including: a variable dimension heat pipe exoskeleton formed of a heat-conductive material by blow molding or additive manufacturing, wherein the variable dimension heat pipe exoskeleton including: a first heat pipe exoskeleton portion with a dimension having a first value; and a second heat pipe exoskeleton portion with the dimension having a second value different from the first value. Further, a method of manufacturing a heat pipe, including: providing a heat-conductive material; and performing blow molding or additive manufacturing to form a variable dimension heat pipe exoskeleton of the heat-conductive material, wherein the heat pipe exoskeleton has a first heat pipe exoskeleton portion with a dimension having a first value, and a second heat pipe exoskeleton portion with the dimension having a second value different from the first value.

Description

TECHNICAL FIELD

Aspects described herein generally relate to heat pipes and, more particularly, to heat pipes with variable dimensions.

BACKGROUND

Many original equipment manufacturers prefer heat pipes to vapor chambers due to their cost effectiveness, lighter weight, and ease of manufacture. However, designers, particularly thermal, mechanical, and hardware engineers, face challenges with heat pipes, such as accommodating acute bends, ensuring comprehensive coverage of hot spots, managing the shared thermal loads of multiple pipes (which increases cost, weight, and complexity), and placing electronic components near these pipes. Traditional heat pipes, typically tubular and flattened for system integration, suffer from performance degradation and require thicker designs to meet thermal requirements (Qmax). In addition, their minimum bend radius limits routing flexibility and component placement.

BRIEF DESCRIPTION OF THE FIGURES

FIGS. 1A-1C illustrate examples of variable dimension heat pipes in accordance with aspects of the disclosure.

FIGS. 2A-21 illustrate a method of manufacturing a variable dimension heat pipe by a blow molding process in accordance with aspects of the disclosure.

FIG. 3 illustrates a method of forming a heat transfer system 300 in accordance with aspects of the disclosure.

DETAILED DESCRIPTION

This disclosure is directed to a heat pipe having variable dimensions, such as length, width, or thickness, produced by a blow molding or additive manufacturing technique. The aspects disclosed here overcome the limitations of existing heat pipes and enable the manufacture of heat pipes in various shapes with adjustable length, thickness, and width as needed. In addition, the disclosed heat pipe reduces bending losses and facilitates flexible heat pipe routing according to system layout and component placement.

FIGS. 1A-1C illustrate examples of variable dimension heat pipes 100 (100A, 100B, 100C) in accordance with aspects of the disclosure. Each of these figures shows a top view, a cross-sectional view, and an exploded section of the cross-sectional view.

FIG. 1A illustrates a first example of a variable dimension heat pipe 100A in accordance with aspects of the disclosure.

The heat pipe 100A comprises a variable dimension heat pipe exoskeleton 110A with a first heat pipe exoskeleton portion 112A and a second heat pipe exoskeleton portion 114A in a T-shaped configuration having horizontal and vertical segments. While maintaining a uniform thickness of 0.8 mm throughout, the heat pipe 100A has a width that varies.

The first heat pipe exoskeleton portion 112A, which is the horizontal segment, has a first width value of 18 mm. The second heat pipe exoskeleton portion 114A, which is the vertical segment, is narrower with a second width value of 12 mm, thus differing from the first heat pipe exoskeleton portion 112A.

The first and second heat pipe exoskeleton portions 112A, 114A extend in different directions. Specifically, the first and second heat pipe exoskeleton portions 112A, 114A extend in directions that are orthogonal.

Further, at least one of the first and second heat pipe exoskeleton portions 112A, 114A includes a curved heat pipe exoskeleton portion 116A having a radius that, as a result of the aspects disclosed herein, may be less than about 5 mm.

FIG. 1B illustrates a second example of a variable dimension heat pipe 100B in accordance with aspects of the disclosure.

The heat pipe 100B comprises a variable dimension heat pipe exoskeleton 110B arranged in a T-shaped configuration having horizontal and vertical segments. The vertical segment is divided into an upper portion, referred to as a first heat pipe exoskeleton portion 112B, and a lower portion, referred to as a second heat pipe exoskeleton portion 114B. The first heat pipe exoskeleton portion 112B, which is the upper portion, has a first thickness value of 0.8 mm. On the other hand, the second heat pipe exoskeleton portion 114B, which is the lower portion, has a second thickness value of 0.6 mm, which makes it thinner than the upper portion. This design feature makes the vertical segment thinner toward the SoC (silicon on Chip) interface.

The first and second heat pipe exoskeleton portions 112B, 114B extend in the same direction and are contiguous end-to-end. In other words, the first and second sections of the heat pipe exoskeleton portions 112B, 114B are aligned in the same direction and are positioned adjacent to each other at their ends.

FIG. 1C illustrates a third example of a variable dimension heat pipe 100C in accordance with aspects of the disclosure.

The heat pipe 100C comprises a variable dimension heat pipe exoskeleton 110C arranged in a T-shaped configuration having horizontal and vertical segments similar to the heat pipe exoskeleton 110B of FIG. 1B. The vertical segment is divided into an upper portion, referred to as a first heat pipe exoskeleton portion 112C, and a lower portion, referred to as a second heat pipe exoskeleton portion 114C. The first heat pipe exoskeleton portion 112C, which is the upper portion, has a first thickness value of 0.8 mm. On the other hand, the second heat pipe exoskeleton portion 114C, which is the lower portion, has a second thickness value of 1 mm, which makes it thicker than the upper portion. This design feature makes the vertical segment thicker toward the SoC (silicon on Chip) interface.

The first and second heat pipe exoskeleton portions 112C, 114C extend in the same direction and are contiguous end-to-end. In other words, the first and second sections of the heat pipe exoskeleton portions 112C, 114C are aligned in the same direction and are positioned adjacent to each other at their ends.

The dimension that varies may be, for example, length, the width, or the thickness. The length, the width, and the thickness are defined in directions that are orthogonal.

The heat-conductive material may comprise copper, a copper alloy, aluminum, an aluminum alloy, titanium, or a titanium alloy.

FIGS. 2A-21 illustrate a method of manufacturing a variable dimension heat pipe 100 by a blow molding process in accordance with aspects of the disclosure. The variable dimension heat pipe 100 has an exoskeleton 110 that is formed of a heat-conductive material by blow molding or additive manufacturing.

By way of overview, the method includes heating copper scrap 21 (or scrap of another heat conductive material) and using air to form it into a hollow shape within a mold cavity 210. The copper scrap 21 is first placed in a hopper 22. It then moves into a cavity that houses a rotating mandrel 23 equipped with heaters 24. These heaters 24 melt the copper and transform it into molten copper 25. The molten copper 25, guided by the rotating mandrel 23, flows into the mold cavity 210. Approaching a die head 26, a blow pin 27 introduces air into a part called a “parison” 28, forming the molten copper 25 into a tubular structure 230. The parison 28 then enters the mold cavity. After the parison 28 is formed, it undergoes various stages 1-8 of processing within the mold cavity 210. These stages are further described with reference to FIGS. 2A-21.

FIG. 2A illustrates stage 1, which is the initial extrusion. This stage includes the initial setup where both mold plates 220 are in an open position. The parison 28, which is a tubular plastic preform, is extruded into the mold cavity 210 in preparation for the subsequent molding process.

FIG. 2B illustrates stage 2, which is molding and forming. In this stage, the mold plates 220 close and enclose the parison 28. The edges of the mold engage in a pinch-off action, effectively sealing the parison 28. At the same time, air is introduced into the interior of the parison 28 through the blow pin 27, causing the parison 28 to expand and conform to the internal contours of the mold. This action forms the heat pipe exoskeleton 110 to the shape and dimensions of the mold

FIG. 2C illustrates stage 3, which is cooling and ejection. After a cooling period that allows the material to set and solidify, the mold plates 220 are reopened. The now solidified heat pipe exoskeleton 110 is removed from the mold while maintaining its structural integrity and dimensional accuracy.

FIG. 2D illustrates stage 4, which is post-extraction processing. After extraction, the heat pipe exoskeleton 110 undergoes further processing. The heat pipe exoskeleton 110 has a T-shaped configuration in this example.

FIG. 2E illustrates stage 5, which is the inspection of the heat pipe exoskeleton 110 after removal from the mold. The heat pipe exoskeleton 110, if it passes inspection, is flat and maintains a uniform thickness throughout, except for certain areas that are designed with different dimensions. The heat pipe exoskeleton 110 has a hollow structure, with one sealed end 116 and two unsealed ends 118 (118.1 and 118.2) to facilitate wick insertion. The number of sealed and unsealed ends may vary based on the specific design specifications of the heat pipe.

FIG. 2F illustrates stage 6, which is wick insertion. The wick 120 is inserted into the unsealed ends 118.1, 118.2 of the heat pipe exoskeleton 110 in alignment with their respective axial directions. During this process, each unsealed end 118 is filled with a heat-conductive material in powder form (such as copper powder), which is then subjected to sintering to create a porous structure that forms the wick 120.

FIG. 2G illustrates stage 7. In this stage, the gravity-side unsealed end 118.2 of the heat pipe exoskeleton 110 is sealed. The other unsealed end 118.1 remains open for subsequent processing. More specifically, a working fluid (e.g., water) is introduced into the interior cavity of the heat pipe exoskeleton 110 via the unsealed end 118.1, after which the structure is hermetically sealed to enclose the working fluid.

FIG. 2H illustrates stage 8, wherein the heat pipe 100 is tested and inspected to ensure its functionality and integrity.

FIG. 2I illustrates the heat pipe 100 after testing and inspection. The illustration includes both top and side views of the heat pipe 100. The horizontal segment of the heat pipe 100 is characterized by a first width W1 and a first thickness T1, while the vertical segment has a second width W2 and a second thickness T2. The first width W1 is different from the second width W2, and similarly, the first thickness T1 is different from the second thickness T2.

The disclosed heat pipe 100, having variable dimensions, can be manufactured in any of a variety of shapes. These shapes include, but are not limited to, alphabetic characters such as B, C, E, F, H, I, J, L, M, N, P, S, T, U, V, W, Y, Z, and numeric digits including 3, 7, 9, and others. This versatility in shape allows for adaptable integration into various applications and systems.

FIG. 3 illustrates a method of forming a heat transfer system 300 in accordance with aspects of the disclosure.

Steps 310-330 outline the process for manufacturing a single heat pipe 100. Step 310 includes providing a heat-conductive material. During step 320, manufacturing processes such as blow molding or additive manufacturing are used to form the heat pipe exoskeleton 110, which has variable dimensions and is made of heat-conductive material. In step 330, a wick 120 is formed within this exoskeleton 110.

Step 340 includes placing the single heat pipe in proximity to a heat source of an electronic device. This configuration allows the heat pipe 100 to effectively dissipate heat from the source, thereby contributing to the overall efficiency of the heat transfer system. It is not necessary to provide multiple heat pipes as in known systems. A single heat pipe 100, in accordance with the aspects disclosed herein, is sufficient.

The disclosed variable dimension heat pipe overcomes the limitations of prior heat pipes by providing design flexibility in shape and thickness. This heat pipe facilitates the placement of CPU core area components (CPU, memory, and power supply) on the printed circuit board (PCB) without the constraints of traditional heat pipe routing. It effectively eliminates vapor chamber dead zones on the motherboard and reduces heat pipe bending losses, thereby improving thermal efficiency. The heat pipe provides superior coverage of system-on-chip (SoC) hot spots, outperforming dual heat pipe thermal designs.

In addition, the disclosed heat pipe increases battery capacity and extends battery life in electronic devices. By minimizing its overlap on the motherboard, it reduces the keepout zone for taller components below, optimizing space utilization. The heat pipe's thermal transfer efficiency (“Qmax”) exceeds that of dual heat pipe systems, contributing to improved overall device performance.

An attribute of this heat pipe is its unrestricted shape, enabling flexible integration across various electronic device designs, including workstations, desktops, and servers. This design offers the potential for weight reduction compared to dual heat pipe systems and also provides a cost-effective alternative to existing heat pipes and vapor chambers. Its adaptability makes it a better solution for managing distributed hot spots in CPUs, GPUs, and VR components, providing it with broad applicability and effectiveness in thermal management.

The techniques of this disclosure may also be described in the following examples.

Example 1. A heat pipe, comprising: a variable dimension heat pipe exoskeleton formed of a heat-conductive material by blow molding or additive manufacturing, wherein the variable dimension heat pipe exoskeleton comprises: a first heat pipe exoskeleton portion with a dimension having a first value; and a second heat pipe exoskeleton portion with the dimension having a second value different from the first value.

Example 2. The heat pipe of example 1, wherein the dimension is length, width, or thickness, and the length, the width, and the thickness are defined in directions that are orthogonal.

Example 3. The heat pipe of any of examples 1-2, wherein at least one of the first and second heat pipe exoskeleton portions includes a curved heat pipe exoskeleton portion having a radius of less than about 5 mm.

Example 4. The heat pipe of any of examples 1-3, wherein the heat pipe exoskeleton is formed by blow molding.

Example 5. The heat pipe of any of examples 1-4, wherein the heat pipe exoskeleton is formed by additive manufacturing.

Example 6. The heat pipe of any of examples 1-5, wherein the first and second heat pipe exoskeleton portions extend in different directions.

Example 7. The heat pipe of any of examples 1-6, wherein the first and second heat pipe exoskeleton portions extend in directions that are orthogonal.

Example 8. The heat pipe of any of examples 1-7, wherein the first and second heat pipe exoskeleton portions extend in a same direction and are contiguous end-to-end.

Example 9. The heat pipe of any of examples 1-8, further comprising: a wick formed within the heat pipe exoskeleton.

Example 10. The heat pipe of any of examples 1-9, wherein the heat-conductive material comprises copper, a copper alloy, aluminum, an aluminum alloy, titanium, or a titanium alloy.

Example 11. A heat transfer system, comprising: a single heat pipe as in any of examples 1-10 operable to dissipate heat from a heat source.

Example 12. A method of manufacturing a heat pipe, comprising: providing a heat-conductive material; and performing blow molding or additive manufacturing to form a variable dimension heat pipe exoskeleton of the heat-conductive material, wherein the heat pipe exoskeleton has a first heat pipe exoskeleton portion with a dimension having a first value, and a second heat pipe exoskeleton portion with the dimension having a second value different from the first value.

Example 13. The method of example 12, wherein the dimension is length, width, or thickness, and the length, the width, and the thickness are defined in directions that are orthogonal.

Example 14. The method of any of examples 12-13, wherein at least one of the first and second heat pipe exoskeleton portions includes a curved heat pipe exoskeleton portion having a radius of less than about 5 mm.

Example 15. The method of any of examples 12-14, further comprising: performing blow molding to form the variable dimension heat pipe exoskeleton.

Example 16. The method of any of examples 12-16, further comprising: performing additive manufacturing to form the variable dimension heat pipe exoskeleton.

Example 17. The method of example 12, further comprising: sealing an end of the heat pipe exoskeleton and leaving any other ends of the heat pipe exoskeleton unsealed; and inserting a wick into each of the unsealed ends of the heat pipe exoskeleton in a respective axial direction.

Example 18. The method of example 17, wherein the inserting the wick into the heat pipe exoskeleton comprises: filling each of the unsealed ends of the heat pipe exoskeleton with a powder of the heat-conductive material; and sintering the powder to form a porous structure forming the wick.

Example 19. The method of example 18, further comprising: sealing any gravity-side unsealed ends of the heat pipe exoskeleton; adding a working fluid into an interior cavity of the heat pipe exoskeleton; and hermetically sealing the heat pipe exoskeleton having the working fluid therein.

Example 20. A method of forming a heat transfer system, comprising: performing a method of manufacturing a single heat pipe as in any of examples 12-19; and place the single heat pipe in proximity to a heat source of an electronic device, wherein the single heat pipe is operable to dissipate heat from the heat source.

While the foregoing has been described in conjunction with exemplary aspect, it is understood that the term “exemplary” is merely meant as an example, rather than the best or optimal. Accordingly, the disclosure is intended to cover alternatives, modifications, and equivalents, which may be included within the scope of the disclosure.

Although specific aspects have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations may be substituted for the specific aspects shown and described without departing from the scope of the present application. This application is intended to cover any adaptations or variations of the specific aspects discussed herein.

Claims

1. A heat pipe, comprising: a variable dimension heat pipe exoskeleton formed of a heat-conductive material by blow molding or additive manufacturing, wherein the variable dimension heat pipe exoskeleton comprises: a first heat pipe exoskeleton portion with a dimension having a first value; anda second heat pipe exoskeleton portion with the dimension having a second value different from the first value.

2. The heat pipe of claim 1, wherein the dimension is length, width, or thickness, and the length, the width, and the thickness are defined in directions that are orthogonal.

3. The heat pipe of claim 1, wherein at least one of the first and second heat pipe exoskeleton portions includes a curved heat pipe exoskeleton portion having a radius of less than about 5 mm.

4. The heat pipe of claim 1, wherein the heat pipe exoskeleton is formed by blow molding.

5. The heat pipe of claim 1, wherein the heat pipe exoskeleton is formed by additive manufacturing.

6. The heat pipe of claim 1, wherein the first and second heat pipe exoskeleton portions extend in different directions.

7. The heat pipe of claim 1, wherein the first and second heat pipe exoskeleton portions extend in directions that are orthogonal.

8. The heat pipe of claim 1, wherein the first and second heat pipe exoskeleton portions extend in a same direction and are contiguous end-to-end.

9. The heat pipe of claim 1, further comprising: a wick formed within the heat pipe exoskeleton.

10. The heat pipe of claim 1, wherein the heat-conductive material comprises copper, a copper alloy, aluminum, an aluminum alloy, titanium, or a titanium alloy.

11. A heat transfer system, comprising: a single heat pipe as claimed in claim 1 operable to dissipate heat from a heat source.

12. A method of manufacturing a heat pipe, comprising: providing a heat-conductive material; andperforming blow molding or additive manufacturing to form a variable dimension heat pipe exoskeleton of the heat-conductive material, wherein the heat pipe exoskeleton has a first heat pipe exoskeleton portion with a dimension having a first value, and a second heat pipe exoskeleton portion with the dimension having a second value different from the first value.

13. The method of claim 12, wherein the dimension is length, width, or thickness, and the length, the width, and the thickness are defined in directions that are orthogonal.

14. The method of claim 12, wherein at least one of the first and second heat pipe exoskeleton portions includes a curved heat pipe exoskeleton portion having a radius of less than about 5 mm.

15. The method of claim 12, further comprising: performing blow molding to form the variable dimension heat pipe exoskeleton.

16. The method of claim 12, further comprising: performing additive manufacturing to form the variable dimension heat pipe exoskeleton.

17. The method of claim 12, further comprising: sealing an end of the heat pipe exoskeleton and leaving any other ends of the heat pipe exoskeleton unsealed; andinserting a wick into each of the unsealed ends of the heat pipe exoskeleton in a respective axial direction.

18. The method of claim 17, wherein the inserting the wick into the heat pipe exoskeleton comprises: filling each of the unsealed ends of the heat pipe exoskeleton with a powder of the heat-conductive material; andsintering the powder to form a porous structure forming the wick.

19. The method of claim 18, further comprising: sealing any gravity-side unsealed ends of the heat pipe exoskeleton;adding a working fluid into an interior cavity of the heat pipe exoskeleton; andhermetically sealing the heat pipe exoskeleton having the working fluid therein.

20. A method of forming a heat transfer system, comprising: performing a method of manufacturing a single heat pipe as claimed in claim 12; andplace the single heat pipe in proximity to a heat source of an electronic device,wherein the single heat pipe is operable to dissipate heat from the heat source.