CN110730579A

CN110730579A - Method for manufacturing electronic device shell with micro-heat pipe function

Info

Publication number: CN110730579A
Application number: CN201810784672.4A
Authority: CN
Inventors: 陈振贤
Original assignee: Guangzhou Lihe Thermal Management Technology Co Ltd
Current assignee: Guangzhou Lihe Thermal Management Technology Co Ltd
Priority date: 2018-07-17
Filing date: 2018-07-17
Publication date: 2020-01-24
Anticipated expiration: 2038-07-17
Also published as: CN110730579B

Abstract

A method for manufacturing an electronic device housing with micro heat pipe function, comprising the steps of: a groove-shaped structure is formed on the inner surface of the electronic device shell. An independent groove-shaped structure corresponding to the groove-shaped structure is manufactured, and a ventilation hole is manufactured on the groove-shaped structure. And manufacturing a capillary structure on the inner surface of the groove-shaped structure body. And manufacturing a duct matched with the ventilation hole on the groove-shaped structure. And hermetically jointing the groove-shaped structural body with the capillary structure with the corresponding groove-shaped structural body to form a flat micro-heat-conducting pipe cavity structure with the capillary structure on the inner surface of the electronic device shell. And injecting working fluid into the cavity structure of the flat micro-heating conduit through the conduit of the groove-shaped structure. The conduit is evacuated and sealed to form a flat micro thermal conduit functional structure in the electronic device housing. By the manufacturing method, a micro heat pipe functional structure with CNC high heat conduction efficiency can be manufactured on the shell of the electronic device, and the supply chain of the heat dissipation element is simplified.

Description

Method for manufacturing electronic device shell with micro-heat pipe function

Technical Field

The invention provides a method for manufacturing a shell with high heat dissipation efficiency, in particular to a method for manufacturing a shell of an electronic device, such as the shell of the electronic device with a micro heat pipe function or a back cover of a handheld communication device, so as to increase the heat dissipation efficiency, the heat dissipation path and the design flexibility in the ultra-thin and narrow heat dissipation management space provided by the electronic device.

Background

The trend of electronic and handheld communication device products is continuously towards ultra-thinning and high-functionality, and demands on the operation speed and functions of a Microprocessor (Microprocessor) in the device are also increasing. The microprocessor is a core element of electronic and communication products, and is a main heating element of an electronic device due to the fact that heat is easily generated under high-speed operation, and if the heat cannot be dissipated in real time, a local processing Hot Spot (Hot Spot) is generated. Without a good thermal management scheme and a heat dissipation system, the microprocessor is often overheated and cannot perform its intended function, which may even affect the lifetime and reliability of the whole electronic device system. Therefore, electronic products need excellent heat dissipation capability, and particularly, ultra-thin electronic devices such as smart phones (smartphones) and Tablet PCs (Tablet PCs) need excellent heat dissipation capability. Currently, an effective way for electronic and communication products to handle the Heat release and dissipation of Hot spots (Hot spots) is to contact one surface of a flat Micro Heat Pipe (Micro Heat Pipe) or a Vapor Chamber (Vapor Chamber) with a Heat source and the other surface with the casing of the electronic device, and it is desired to conduct and distribute the high Heat generated by a microprocessor to the casing in a more effective way, thereby radiating the Heat to the air.

The micro-heat pipe or the temperature equalizing plate is basically a closed cavity containing working fluid, and the purpose of heat transfer is achieved through the liquid-gas two-phase change of the continuous circulation of the working fluid in the cavity and the gas-liquid return convection between the gas and the liquid at the heat absorption end and the heat release end. Generally, the micro heat pipe is in a long cylindrical shape, and the larger the inner cavity space is, the faster the convection speed is, and the better the heat conduction and the heat dissipation are. However, in order to meet the requirement of ultra-thinning of electronic products, the prior art needs to re-process the heat pipe into a flat and long shape for disposing in the space of the enclosure with a narrow height, even requiring an ultra-thin micro heat pipe with a thickness less than 0.5 mm.

At present, smart phones with body thickness less than 5mm are already on the market. The thickness of the back cover of the mobile phone is usually less than 1.0mm, and the space for plugging the flat micro heat pipe is only left between 0.3mm and 0.4mm from the surface of the microprocessor on the circuit board and the inner surface of the back cover of the mobile phone. If the ultra-thin micro-heating conduit is manufactured by flattening a copper pipe with the pipe diameter of 2mm, the height of the inner cavity of the flat micro-heating conduit can be only about 0.1 mm-0.2 mm by deducting the thickness of the upper wall and the lower wall. The width of the heat pipe cavity is relatively flattened to less than about 3mAnd m is selected. Therefore, the cross section area of the cavity in the ultra-thin micro heat pipe is only about 0.3mm²～0.6mm²In the meantime. Such a small convective vapor gas channel greatly limits the heat-releasing and dissipating effects of the micro-thermal conduit, and further cannot cope with the increasing heat-dissipating function of the microprocessor.

For the fast-leap-forward chip processing speed, the sectional area of the existing heat pipe cavity obviously cannot meet the requirements of heat clearing and heat dissipation of future ultra-thin electronic and communication devices. Therefore, how to conduct and dissipate heat quickly in the limited thickness and space of the electronic product is a problem to be solved.

Disclosure of Invention

In view of the above, the present invention provides a method for manufacturing a casing or a back cover of an electronic device having a micro heat pipe function to achieve direct and efficient heat dissipation, which is different from the conventional methods for manufacturing and combining the casing and the micro heat pipe of the electronic device, and can greatly improve the heat dissipation efficiency of a microprocessor hot spot in an electronic device system in a limited narrow thickness space provided in the design of the electronic device system. In practice, the invention optimizes the heat dissipation management design and flexibility of the electronic device system, and simplifies the supply chain of the whole heat dissipation element industry.

The invention relates to a method for manufacturing an electronic device shell with a micro-heat pipe function, which comprises the following steps: an electronic device housing is provided. Manufacturing N strip-shaped grooves on the inner surface of the electronic device shell to form N groove-shaped structures. N independent groove-shaped structures corresponding to the N groove-shaped structures are manufactured according to the N strip-shaped grooves, and a ventilation hole is manufactured on each groove-shaped structure. A first capillary structure is formed on the inner surface of each of the trench-shaped structures. And manufacturing a conduit matched with the ventilation hole on each groove-shaped structure body, so that one end of the conduit is communicated with the ventilation hole. And hermetically jointing the N groove-shaped structures with the first capillary structure with the corresponding N groove-shaped structures on the inner surface of the electronic device shell so as to form N flat micro-heat-conducting pipe cavity structures with the first capillary structure on the inner surface of the electronic device shell. Injecting a working fluid into each flat micro-heat pipe cavity structure on the inner surface of the electronic device casing through the pipe of each groove-shaped structure. And vacuumizing and sealing the guide pipe to form N flat micro heat guide pipe functional structures on the inner surface of the electronic device shell, so that the electronic device shell has N micro heat guide pipe functions. Wherein N is 1 or a natural number more than 1.

The electronic device casing is made of hard materials such as metal, glass or ceramic.

Moreover, the appearance of the N flat micro-thermal conduit functional structures is single strip or multi-head strip, and the appearance of the N flat micro-thermal conduit functional structures can also present various shapes according to the optimal design of heat dissipation and heat soaking.

In one embodiment, the outer surfaces of the N trench-shaped structures have M heat source contact regions, where M is a natural number greater than or equal to 1. When M is equal to 1, the appearance of the flat micro-heat pipe structure on the shell of the electronic device is in a single strip shape; when M is larger than 1, the flat micro-heat pipe structure on the electronic device shell is in a multi-head strip-shaped or polygonal structure.

In the step of airtightly bonding the N groove-shaped structures with the first capillary structure to the corresponding N groove-shaped structures on the inner surface of the electronic device shell to form N flat micro-heat conducting pipe cavity structures with the first capillary structure on the inner surface of the electronic device shell, the N groove-shaped structures and each corresponding independent groove-shaped structure are airtightly bonded by using a gluing method or a welding method respectively.

The first capillary structure is formed on the inner surface of each groove structure independently by coating a slurry containing powder particles on the inner surface of each groove structure, and heating to a temperature at which the powder particles are bonded to the inner surface and bonded to each other to form an irregular capillary structure. The step of forming the capillary structure further comprises the following substeps: a first solder powder and a second powder having solderability on the surface are mixed to form a third powder. And preparing the third powder into a slurry with viscosity and rheological property. The slurry is applied to the weldable inner surface of each of the trench-shaped structures. Heating the N independent groove-shaped structures to a temperature exceeding the melting point of the first solder powder to form the first capillary structure of each independent groove-shaped structure. Wherein the slurry is laid on the inner surface of each independent groove-shaped structure in a steel plate printing, screen printing or spraying mode.

Wherein the melting point of the first solder powder is lower than the melting point of the second powder.

In the step of heating the N independent groove-shaped structures to a temperature at least the melting point of the first solder powder but less than the melting point of the second powder to form the first capillary structure of each of the independent groove-shaped structures. The first solder powder and the second solder powder are different in material, powder particle size and distribution.

In one embodiment, the electronic device housing is a back cover of an electronic device. Further, the back cover is a back cover of a smart phone, a notebook computer, a portable computer, a tablet computer, a music player, a media player, a navigator, a game console or a display, etc.

In the step of fabricating a conduit in the vent hole, the conduit extends from the outer surface of the N trench-shaped structures in a direction away from the inner surface of the N trench-shaped structures.

The invention also provides another method for manufacturing the electronic device shell with the function of the micro heat pipe. The method comprises the following steps: an electronic device housing is provided. Manufacturing N strip-shaped grooves on the inner surface of the electronic device shell to form N groove-shaped structures. A heat insulation structure layer is arranged in each groove-shaped structure body to respectively form a heat insulation structure. And manufacturing N independent groove-shaped structural bodies corresponding to the N groove-shaped structural bodies according to the N strip-shaped grooves. A first capillary structure and a vent hole are formed on the inner surface of each independent groove-shaped structure. And hermetically jointing the N independent groove-shaped structures on the corresponding N groove-shaped structures on the inner surface of the electronic device shell so as to form N flat micro-heat-conducting-pipe cavity structures on the inner surface of the electronic device shell. And respectively injecting a working fluid into each flat micro-heat pipe cavity structure on the inner surface of the shell of the electronic device through the ventilation hole of each groove-shaped structure. And vacuumizing and sealing each conduit to form N flat micro heat conduit functional structures on the inner surface of the electronic device shell, so that the electronic device shell has N micro heat conduit functions. Wherein N is 1 or a natural number more than 1.

The invention also provides another method for manufacturing the electronic device shell with the function of the micro heat pipe. The method comprises the following steps: an electronic device housing is provided. Manufacturing N strip-shaped grooves on the inner surface of the electronic device shell to form N groove-shaped structures. A mesh structure layer is arranged in each groove-shaped structure body to respectively form a mesh second capillary structure. And manufacturing N independent groove-shaped structural bodies corresponding to the N groove-shaped structural bodies according to the N strip-shaped grooves. A first capillary structure and a vent hole are formed on the inner surface of each independent groove-shaped structure. And hermetically jointing the N independent groove-shaped structures on the corresponding N groove-shaped structures on the inner surface of the electronic device shell so as to form N flat micro-heat-conducting-pipe cavity structures on the inner surface of the electronic device shell. And respectively injecting a working fluid into each flat micro-heat pipe cavity structure on the inner surface of the shell of the electronic device through the ventilation hole of each groove-shaped structure. And vacuumizing and sealing each conduit to form N flat micro heat conduit functional structures on the inner surface of the electronic device shell, so that the electronic device shell has N micro heat conduit functions. Wherein N is 1 or a natural number more than 1.

The invention also provides another method for manufacturing the electronic device shell with the function of the micro heat pipe. The method comprises the following steps: providing an electronic device shell; manufacturing N strip-shaped grooves on the inner surface of the electronic device shell to form N groove-shaped structural bodies; arranging a heat insulation layer structure layer in each groove-shaped structure body to respectively form a heat insulation structure; arranging a reticular structure layer on the heat insulation layer structure layer in each groove-shaped structure body to respectively form a reticular second capillary structure; manufacturing N independent groove-shaped structural bodies corresponding to the N groove-shaped structural bodies according to the N strip-shaped grooves; manufacturing a first capillary structure and a ventilation hole on the inner surface of each independent groove-shaped structure; manufacturing a conduit matched with the ventilation hole on each groove-shaped structure, and enabling one end of the conduit to be communicated with the ventilation hole; hermetically connecting the N independent groove-shaped structures to the N corresponding groove-shaped structures on the inner surface of the electronic device shell so as to form N flat micro-thermal conduit cavity structures on the inner surface of the electronic device shell; respectively injecting a working fluid into each flat micro-heat pipe cavity structure on the inner surface of the electronic device shell through the ventilation hole of each groove-shaped structure; vacuumizing and sealing each conduit to form N flat micro-heat conduit structures on the inner surface of the electronic device shell so that the electronic device shell has the functions of N micro-heat conduits; wherein N is 1 or a natural number more than 1.

In summary, the method for manufacturing the casing of the electronic device with the function of the micro heat pipe according to the present invention is different from the conventional concept of combining the micro heat pipe and the casing together after the micro heat pipe and the casing are separately manufactured and processed. The shell or the back cover of the electronic device manufactured by the invention has the functions of a Micro heat pipe (Micro HeatPipe) and a Vapor Chamber (Vapor Chamber). The method is beneficial to the designer of the electronic or communication device to keep larger heat dissipation design space and design flexibility when designing the configuration of the internal parts of the electronic device, and simultaneously, the electronic and communication system can have larger heat clearing and heat dissipation capacity under the limitation of narrow thickness space. In addition, the functional structure of the micro duct on the casing of the electronic device is designed to be beneficial to improving the production efficiency of the whole product. Compared with the combination of the micro heat pipe radiating module and the casing (back cover) in the ultra-thin electronic device (smart phone) in the prior art, the electronic device casing manufactured by the method can have a larger micro heat pipe cavity Structure so as to be beneficial to better manufacturing a capillary Structure (Wick Structure) and a smoother steam guide channel, thereby achieving a better radiating effect of the whole electronic device. Further, the industrial supply chain of the heat dissipation element of the electronic device is simplified.

Drawings

Fig. 1A is a schematic diagram illustrating an electronic device system.

Fig. 1B is a schematic view showing an inner surface of a casing of an electronic device corresponding to fig. 1A.

FIG. 1C is a sectional view along A-A showing the inner surface of the electronic device housing corresponding to FIG. 1B.

Fig. 2 is a schematic view showing a groove-shaped structure corresponding to the groove-shaped structure in the present invention.

Fig. 3A is a cross-sectional view along B-B showing the trench-shaped structure corresponding to fig. 2.

Fig. 3B is a cross-sectional view along C-C showing the trench-shaped structure corresponding to fig. 2.

Fig. 3C is a sectional view showing a first capillary structure corresponding to the inner surface of the groove-shaped structure of fig. 3A.

Fig. 3D is a sectional view showing the groove-shaped structure and the duct corresponding to fig. 3B.

Fig. 4A is a schematic view showing joining of a groove-shaped structure and a groove-shaped structure.

Fig. 4B is a schematic view showing joining of the groove-shaped structure and the groove-shaped structure corresponding to fig. 3C.

Fig. 4C is a schematic view showing joining of the groove-shaped structure and the groove-shaped structure corresponding to fig. 3D.

Fig. 5A to 5D are schematic diagrams illustrating the structural configuration changes of the flat micro thermal catheter in different embodiments.

Fig. 6A is a schematic diagram illustrating making a slurry.

Fig. 6B and 6C are schematic diagrams illustrating the application of slurry to the trench-shaped structure in one embodiment.

Fig. 7A-7D are flowcharts illustrating steps in various embodiments of the present invention.

Fig. 8 is a flow chart illustrating steps for fabricating a first capillary structure in an embodiment of the invention.

Fig. 9A is a schematic diagram showing the structure of a thermal insulation layer in one embodiment of the present invention.

Fig. 9B is a schematic diagram illustrating a mesh-like secondary capillary structure in another embodiment of the invention.

FIG. 9C is a schematic diagram showing a thermal insulating layer structure and a mesh-like secondary wick structure in yet another embodiment of the present invention.

Description of the symbols

1: electronic device housing 31: outer surface

2: the electronic device system 32: inner surface

3: groove-shaped structure 33: support column

12: case inner surface 35: first capillary structure

13: groove-shaped structure 36: heat source contact area

14: insulating layer structure 37: catheter tube

15: mesh-like second capillary structure 41: first solder powder

16: airtight joint 42: a second powder

20: heating element 43: third powder

28: battery 44: slurry material

29: circuit board 50: steel plate

30: the vent holes 51: scraping knife

Detailed Description

In order that the advantages, concepts and features of the invention will be readily and clearly understood, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. It is to be understood that these embodiments are merely representative examples of the present invention, and that no limitation on the scope of the invention or its corresponding embodiments is intended by the specific methods, devices, conditions, materials, etc., illustrated herein.

In the description of the present invention, it is to be understood that the terms "longitudinal, transverse, upper, lower, front, rear, left, right, top, bottom, inner, outer" and the like refer to orientations or positional relationships based on those shown in the drawings, which are for convenience of description and simplicity of description, and do not indicate that the device or component being described must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.

In addition, the indefinite articles "a", "an" and "an" preceding an apparatus or element of the invention are not intended to limit the number requirement (i.e., the number of occurrences) of the apparatus or element. Thus, "a" or "an" should be read to include one or at least one, and the singular form of a device or element also includes the plural form unless the number clearly indicates the singular form.

Please refer to fig. 1A to 1C, fig. 2, fig. 3A to 3D, fig. 4A to 4C, fig. 5A and fig. 7A. Fig. 1A is a schematic diagram illustrating an electronic device system. Fig. 1B is a schematic view showing an inner surface of a casing of an electronic device corresponding to fig. 1A. FIG. 1C is a sectional view along A-A showing the inner surface of the electronic device housing corresponding to FIG. 1B. Fig. 2 is a schematic view showing a groove-shaped structure corresponding to the groove-shaped structure in the present invention. Fig. 3A is a cross-sectional view along B-B showing the trench-shaped structure corresponding to fig. 2. Fig. 3B is a cross-sectional view along C-C showing the trench-shaped structure corresponding to fig. 2. Fig. 3C is a sectional view showing a first capillary structure corresponding to the inner surface of the groove-shaped structure of fig. 3A. Fig. 3D is a sectional view showing the groove-shaped structure and the duct corresponding to fig. 3B. Fig. 4A is a schematic view showing joining of a groove-shaped structure and a groove-shaped structure. Fig. 4B is a schematic view showing joining of the groove-shaped structure and the groove-shaped structure corresponding to fig. 3C. Fig. 4C is a schematic view showing joining of the groove-shaped structure and the groove-shaped structure corresponding to fig. 3D. Wherein the oblique lines in fig. 3B, 3D and 4C are shown at the cross-sections of the pipes or holes. FIG. 7A is a flow chart illustrating steps in one embodiment of the present invention.

The invention relates to a method for manufacturing an electronic device shell 1 with a micro-heat pipe function, which comprises the following steps: an electronic device housing 1 is provided. N strip-shaped grooves are formed on the inner surface 12 of the electronic device housing 1 to form N groove-shaped structures 13, as shown in fig. 1B and 1C. Based on the N strip-shaped grooves, N independent groove-shaped structures 3 corresponding to the N groove-shaped structures 13 are formed, and a vent hole 30 is formed in each groove-shaped structure 3, as shown in fig. 2. A first capillary structure 35 is formed on the inner surface 32 of each of the individual groove-shaped structures 3, as shown in fig. 3C. A duct 37 matching the ventilation hole 30 is formed on each groove-shaped structure 3, such that one end of the duct 37 is connected to the ventilation hole 30, as shown in fig. 3D. The N groove-shaped structures 3 with the first capillary structures 35 are hermetically bonded to the corresponding N groove-shaped structures 13 on the inner surface 12 of the housing of the electronic device 1, so as to form N flat micro heat pipe cavity structures with the first capillary structures 35 on the inner surface 12 of the housing of the electronic device 1, as shown in fig. 4A and 4B. Injecting a working fluid into each flat micro heat pipe cavity structure of the inner surface 12 of the casing of the electronic device 1 through the pipe 37 of each groove-shaped structure 3. The conduit 37 is evacuated and sealed to form N flat micro heat pipe functional structures on the inner surface 12 of the electronic device casing 1, so that the electronic device casing 1 has N micro heat pipe functions, as shown in fig. 5A. Wherein N is 1 or a natural number more than 1.

As shown in fig. 1A and 1B, the shape of the strip-shaped groove of the electronic device housing 1 corresponds to an electronic device system 2. For example, the electronic device system 2 is a smart phone, which includes a battery 28 and a circuit board 29 inside, and the electronic device housing 1 is a back cover of the smart phone. The circuit board 29 has at least one heating element 20, typically a processor, thereon. In the prior art, a micro heat pipe manufacturer processes and flattens a tubular elongated micro heat pipe into an ultra-thin micro heat pipe according to the specification requirement of the electronic device system 2. Moreover, the ultra-thin micro heat pipe is bent to avoid the space occupied by the battery 28 and contact the heating element 20 when being attached to the electronic device system 2. However, as described in the prior art, the prior art method has the problems of small space of the cavity in the micro heat pipe and low heat conduction efficiency. At present, the smart phone provided with the micro heat pipe on the market can provide the space between the inner surface of the shell and the surface of the microprocessor with the thickness of the micro heat pipe which is only 0.35 mm-0.4 mm or even lower. To achieve this thickness, the micro thermal catheter can only be made of copper tubing of 2mm diameter and flattened. After the ultra-thin micro-heat pipe with the thickness is flattened and the pipe wall thicknesses of the upper surface and the lower surface are deducted, the height of the cavity structure of the heat pipe is only about 0.15 mm-0.2 mm. Plus flattening of 2mm pipe diameterWidth limitations, such as a heat pipe having a total length of 100mm, have a total cavity volume of only about 45mm cubic (mm)³) 60mm cube (mm)³). In addition, the capillary structure is formed on the wall of the cavity, which makes the air passage space for the vapor to rapidly take away the latent heat from the vapor in the evaporation area to the condensation area narrower. In the face of the further requirement of mobile phone brands to reduce the thickness space allowed by the heat dissipation element to only 0.3mm or less, it is more difficult for manufacturers of micro heat pipes to manufacture ultra-thin micro heat pipes meeting the heat dissipation requirement of mobile phone factories.

The invention can design the structure of flat micro heat pipe structure on the inner surface of the shell of the electronic device, which uses the space inside the shell of the electronic device as a part of the cavity structure of the micro heat pipe and breaks through the width limitation of a 2mm diameter round pipe after being flattened, thereby maximizing the cavity structure of the micro heat pipe and greatly improving the heat dissipation efficiency of the whole electronic device. Moreover, the flat micro heat pipe cavity structure can be manufactured when the electronic device casing 1 is manufactured directly according to the design requirements of the electronic device manufacturer, so that the electronic device casing or the back cover has the functions of the micro heat pipe and the temperature equalization plate, and the industrial integration and design are facilitated.

The electronic device casing is made of hard materials such as metal, glass or ceramic, and N strip-shaped grooves can be precisely manufactured on the inner surface of the casing directly by a numerical control (CNC) milling machine to be used as a part of the cavity structure of the flat micro-heating conduit.

As shown in fig. 2 and fig. 3A, in an embodiment, the groove-shaped structure 3 further has a supporting pillar 33 for supporting the cavity structure of the flat micro heat pipe, so as to prevent the cavity structure of the flat micro heat pipe from deforming after vacuum-pumping. The support posts 33 may be single point posts or lined walls interspersed within the flat micro heat pipe cavity structure. In one embodiment, the support posts 33 do not separate the space within the cavity structure of the flat micro thermal conduit, thereby maintaining gas communication within the cavity. In another embodiment, the support posts 33 divide the space within the cavity structure of the flat micro thermal conduit into more than two chambers.

As shown in fig. 3B, 3D and 4C, in the step of forming a conduit 37 matching with the vent hole 30 on each of the groove-shaped structures 3, so that one end of the conduit 37 is connected to the vent hole 30, the conduit 37 extends from the outer surface 31 of the N groove-shaped structures 3 to a direction away from the inner surface 32 of the N groove-shaped structures 3. When the guide tube 37 extends in this direction, not to the side, it is advantageous in mass production in this step. The outer surfaces 31 of the plurality of groove-shaped structures 3 of the plurality of electronic device cases or back covers are faced upward at a time, and a machine tool can inject working fluid, vacuumize, seal the pipe 37, and the like from above each groove-shaped structure 3 at one time or continuously. The design is beneficial to the mass production operation of manufacturing the electronic device shell or the back cover with the function of the micro-heat pipe.

As shown in fig. 3A to 3D and fig. 4A to 4C, in the step of hermetically bonding N groove-shaped structures 3 having the first capillary structures 35 to the corresponding N groove-shaped structures 13 on the inner surface 12 of the housing 1 of the electronic device to form N flat micro-thermal conduit cavity structures having the first capillary structures 35 on the inner surface 12 of the housing 1 of the electronic device, the N groove-shaped structures 13 and each corresponding independent groove-shaped structure 3 are hermetically bonded by using a gluing method or a welding method, respectively. In practice, the electronic device housing 1 may be laid flat with the inner surface 12 facing upward, and the inner surface 32 of the channel-shaped structure 3 facing downward and approaching and embedding in the direction D1 into the groove-shaped structure of the inner surface 12 of the housing. After embedding, the groove-shaped structures 13 are glued or welded to the groove-shaped structures 3 and form gas-tight joints 16.

Please refer to fig. 5A to 5D. Fig. 5A to 5D are schematic diagrams illustrating the structural configuration changes of the flat micro thermal catheter in different embodiments. The appearance of the N flat micro-heat guide pipe structures can be a single strip shape or a multi-head strip shape or a polygon. In one embodiment, the outer surface 31 of the N trench-shaped structures 3 has M heat source contact areas 36, where M is a natural number greater than or equal to 1. The heat source contact area 36 is used to contact the heat generating element of the electronic device system. Therefore, one end of the heat source contact region 36 of the groove-shaped structure body 3 may be regarded as a heat absorbing end of the heat pipe structure, and one end of the groove-shaped structure body 3 away from the heat source contact region 36 may be regarded as a heat radiating end of the heat pipe structure. In one embodiment, the heat source contact area 36 is a circular structure with a large area, and can be directly attached to a microprocessor and a heating element on a PCB of an electronic device. It functions like a vapor chamber (vapor chamber).

When M equals 1 and N equals 1, the appearance of the flat micro thermal catheter structure is a single strip, as shown in fig. 5A. When M is greater than 1 and N is equal to 1, the flat micro heat pipe structure is shaped like a long strip with multiple ends, as shown in fig. 5B. When M equals to N equals to 2, the inner surface 12 of the electronic device housing 1 has two single elongated flat micro heat conducting pipes, as shown in fig. 5C. When M equals 5 and N equals 2, the inner surface 12 of the electronic device casing 1 has two long-striped flat micro heat pipes with multiple heads, as shown in fig. 5D. The design of the electronic device system with various heat dissipation requirements is not limited to the shape of a single strip, unlike the prior art micro heat pipe. The above are only examples performed according to the method of the present invention, and do not limit the appearance of the electronic device housing having the micro heat pipe function structure.

Please refer to fig. 6A to 6C and fig. 8. Fig. 6A is a schematic diagram illustrating making a slurry. Fig. 6B and 6C are schematic diagrams illustrating the application of slurry to the trench-shaped structure in one embodiment. Fig. 8 is a flow chart illustrating steps for fabricating a first capillary structure in an embodiment of the invention. The step of forming the first capillary structure 35 on the inner surface 32 of each of the individual groove-shaped structures 3 further includes the following substeps: a first solder powder 41 and a second powder 42 having solderability on the surface are mixed to form a third powder 43. The third powder 43 is added to a solvent to form a slurry 44 having viscosity and rheology as shown in fig. 6A. The slurry 44 is laid on the inner surface 32 of each of the groove-shaped structures 3 as shown in fig. 6B and 6C. The N independent groove-shaped structures 3 are heated to a temperature exceeding the melting point of the first solder powder 41 to form the first capillary structure 35 of each independent groove-shaped structure 3. Wherein the melting point of the first solder powder 41 is lower than the melting point of the second solder powder 42.

In the step of heating the N independent groove-shaped structures 3 to a temperature at least the melting point of the first solder powder 41 but less than the melting point of the second powder 42 to form the first capillary structure 35 of each of the independent groove-shaped structures 3. The first solder powder 41 and the second solder powder 42 are different in material, powder particle size, and distribution. The first solder powder 41 may be made of a solder alloy, such as a tin-lead alloy (Sn/Pb), a tin-silver-copper alloy (Sn/Ag/Cu), a tin-copper alloy (Sn/Cu), a tin-bismuth alloy (Sn/Bi), or a tin-zinc alloy (Sn/Bi). The second powder 42 may be copper (Cu) or other powder having surface solderability. In the heating step, the first solder powder 41 having a low melting point is melted into a solder so that the second powder 42 having surface weldability is welded to the inner surface 32 of the groove-shaped structural body 3 and the surfaces of the parts between the particles are welded to each other, but the second powder 42 having a high melting point is not melted.

When the inner surface 32 of the groove-shaped structural body 3 is cooled to room temperature or below the first melting point, the solder solidifies to stabilize the distribution of the second powder 42. At this time, the solder may bond second powder 42 to inner surface 32, or may bond adjacent particles of second powder 42. Thus, the second powder 42 may form a multi-layered stacked and irregularly shaped capillary structure. In the existing technology for manufacturing a capillary structure of Sintered Powder (Sintered Powder), expensive heat energy generation equipment, precise temperature control and a large amount of energy consumption are needed for sintering copper Powder with a high melting point (1085 ℃) onto the inner surface of a copper pipe at a high temperature. In the method, the copper powder is not required to be sintered at high temperature to form a capillary structure on the surface of the copper material; instead, the first solder powder 41 having a low melting point is melted at a low temperature. Therefore, when the method of the invention is used for manufacturing the flat heat pipe structure, the heating equipment with lower cost can be used, the temperature control only needs to be at the first melting point or between the first melting point and the second melting point, less energy is consumed, the heating time is shorter, and the like.

For the efficiency of the step of laying the third powder 43 and the step of welding the third powder 43 in increased production, a solvent may be added to the third powder 43 to make a slurry 44 having viscosity and rheological properties. In practice, the viscosity and rheological property of the slurry 44 can be adjusted by changing the type and proportion of the solvent according to different powder materials and processing modes. Wherein the paste 44 is applied to the inner surface 32 of each individual channel-shaped structure 3 by means of stencil printing, screen printing or spraying. In one embodiment, the channel-shaped structure 3 is placed under a steel plate or screen 50 with the inner surface 32 facing upward, as shown in fig. 6B and 6C. The stencil or screen 50 has holes or grooves, indicated by diagonal lines in the figure. A scraper 51 is used to scrape the slurry 44 in the direction D2, as shown in fig. 6B. The slurry 44 falls down to the inner surface 32 of the channel-shaped structure 3 at the holes, thereby completing the laying of the slurry 44 onto the inner surface 32, as shown in fig. 6C. Further control of the solid content and the rheological property of the slurry can control the thickness of the first capillary structure.

The electronic device enclosure 1 with micro heat pipe function is a housing of an electronic device system 2, and can be a back cover. Further, the back cover is a back cover of a smart phone, a notebook computer, a portable computer, a tablet computer, a music player, a media player, a navigator, a game console, or a display, or any other electronic device system 2. That is, the electronic device housing 1 of the present invention can be used in various electronic device systems 2 to achieve integration of the electronic device systems in thermal management design and achieve efficient heat dissipation and heat dissipation effects. In the prior art, after the internal design of the electronic device is completed, the manufacturing of the electronic device housing, the manufacturing and processing of the micro heat pipe, and the assembling of the electronic device housing and the micro heat pipe are respectively manufactured by different production lines, which results in complicated division of industrial supply chain. The method can complete the electronic device shell with the function of the micro-heat pipe in a single production line, improves the design flexibility of the heat dissipation system of the electronic device, and simplifies the industrial supply chain.

In the prior art, a thermal conductive element of a casing of an electronic device is a round tube and a strip-shaped micro-thermal conduit, which is flattened and then attached to a formed casing, so that the height and the width are limited. However, the height and width of the cavity structure of the flat micro heat pipe of the electronic device housing with the function of the micro heat pipe manufactured by the method of the present invention can be flexibly designed. Therefore, the invention is particularly suitable for manufacturing the electronic device shell with the flat display screen so as to meet the requirements of the electronic device with the screen on large screen and small thickness. The electronic device casing 1 manufactured by the invention can be a back cover of a smart phone, a notebook computer, a tablet personal computer and the like relative to a flat panel display, and can also be a casing of a non-screen area in an electronic device, such as a keyboard area lower casing of the notebook computer.

Please refer to fig. 1A to 1C, fig. 2, fig. 3A to 3D, fig. 4A to 4C, fig. 5A, fig. 7B, and fig. 9A. FIG. 7B is a flow chart illustrating steps in one embodiment of the present invention. Fig. 9A is a schematic diagram showing the structure of a thermal insulation layer in one embodiment of the present invention. The invention also provides another method for manufacturing the electronic device shell with the function of the micro heat pipe. The method comprises the following steps: an electronic device housing 1 is provided. N strip-shaped grooves are formed on the inner surface of the electronic device housing to form N groove-shaped structures 13, as shown in fig. 1B. A heat insulation layer structure 14 is disposed in each of the groove-shaped structures 13 to form a heat insulation structure. N independent trench-shaped structures 3 corresponding to the N groove-shaped structures are fabricated according to the N strip-shaped trenches, as shown in fig. 2. A first capillary structure 35 and a vent hole 30 are formed on the inner surface 32 of each of the individual groove-shaped structures 3. N independent groove-shaped structures 3 are hermetically connected with N corresponding groove-shaped structures 13 on the inner surface 12 of the shell of the electronic device shell 1, so that N flat micro heat pipe cavity structures are formed on the inner surface 12 of the shell of the electronic device shell 1, and one side of each cavity structure is provided with a heat insulation layer structure. Injecting a working fluid into each cavity structure of the flat micro heat pipe on the inner surface 12 of the casing 1 of the electronic device through the vent hole 30 of each groove-shaped structure 3. Each conduit 37 is evacuated and sealed to form N flat micro heat pipe functional structures on the inner surface 12 of the electronic device casing 1, so that the electronic device casing 1 has N micro heat pipe functions. Wherein N is 1 or a natural number more than 1. The manufacturing method adds a heat insulating layer structure 14 on the other surface of the cavity structure relative to the first capillary structure 35, and aims to prevent the high-temperature latent heat carried by the vapor when the phase of the working fluid at the heat absorbing end (Evaporator) of the micro heat pipe structure is changed from being directly conducted from the inner surface of the shell of the electronic device to the outer surface of the shell of the heat absorbing end. An insulating layer structure 14 is disposed in a partial region of the entire cavity structure of the flat micro heat pipe near the heat absorbing end, which helps to form a condensation end (Condensor) at the far end of the micro heat pipe structure and reduces the concentration of the surface temperature of the electronic enclosure.

Please refer to fig. 1A to 1C, fig. 2, fig. 3A to 3D, fig. 4A to 4C, fig. 5A, fig. 7C, and fig. 9B. FIG. 7C is a flow chart illustrating steps in one embodiment of the present invention. Fig. 9B is a schematic diagram illustrating a mesh-like secondary capillary structure in another embodiment of the invention. The invention also provides another method for manufacturing the electronic device shell with the function of the micro heat pipe. The method comprises the following steps: an electronic device housing 1 is provided. N strip grooves are formed on the inner surface of the electronic device housing to form N groove-shaped structures 13. A mesh structure layer is disposed in each of the groove-shaped structures 13 to form a mesh second capillary structure 15, as shown in FIG. 9B. N independent trench-shaped structures 3 corresponding to the N groove-shaped structures are fabricated according to the N strip-shaped trenches, as shown in fig. 2. A first capillary structure 35 and a vent hole 30 are formed on the inner surface 32 of each of the individual groove-shaped structures 3. And hermetically jointing the N independent groove-shaped structures 3 with the corresponding N groove-shaped structures 13 on the inner surface 12 of the shell of the electronic device shell 1 so as to form N flat micro heat pipe cavity structures on the inner surface 12 of the shell of the electronic device shell 1. Injecting a working fluid into each cavity structure of the flat micro heat pipe on the inner surface 12 of the casing 1 of the electronic device through the vent hole 30 of each groove-shaped structure 3. Each conduit 37 is evacuated and sealed to form N flat micro heat pipe functional structures on the inner surface 12 of the electronic device casing 1, so that the electronic device casing 1 has N micro heat pipe functions. Wherein N is 1 or a natural number more than 1. The method changes partial steps, but can simply manufacture the second capillary structure on the surface of the groove-shaped structure body 13, so that a flat micro-heat pipe functional structure with better heat conduction effect can be manufactured on the inner surface of the shell of the electronic device. The manufacturing method adds a second reticular capillary structure on the other surface of the cavity structure relative to the first capillary structure, and is estimated to increase the heat dissipation function of the electronic device shell with the function of micro heat pipe.

Please refer to fig. 1A to 1C, fig. 2, fig. 3A to 3D, fig. 4A to 4C, fig. 5A, fig. 7D, and fig. 9C. FIG. 7D is a flow chart illustrating steps in an embodiment of the present invention. FIG. 9C is a schematic diagram showing a thermal insulating layer structure and a mesh-like secondary wick structure in yet another embodiment of the present invention. The invention also provides another method for manufacturing the electronic device shell with the function of the micro heat pipe. The method comprises the following steps: an electronic device housing 1 is provided. N strip-shaped grooves are formed on the inner surface of the electronic device housing to form N groove-shaped structures 13, as shown in fig. 1B. A heat insulation layer structure 14 is arranged in each groove-shaped structure body 13 to form a heat insulation structure respectively, and a reticular structure layer is arranged on the heat insulation layer structure layer in each groove-shaped structure body to form a reticular second capillary structure 15 respectively. N independent trench-shaped structures 3 corresponding to the N groove-shaped structures are fabricated according to the N strip-shaped trenches, as shown in fig. 2. A first capillary structure 35 and a vent hole 30 are formed on the inner surface 32 of each of the individual groove-shaped structures 3. And hermetically jointing the N independent groove-shaped structures 3 with the corresponding N groove-shaped structures 13 on the inner surface 12 of the shell of the electronic device shell 1 so as to form N flat micro heat pipe cavity structures on the inner surface 12 of the shell of the electronic device shell 1. Injecting a working fluid into each cavity structure of the flat micro heat pipe on the inner surface 12 of the casing 1 of the electronic device through the vent hole 30 of each groove-shaped structure 3. Each conduit 37 is evacuated and sealed to form N flat micro heat pipe functional structures on the inner surface 12 of the electronic device casing 1, so that the electronic device casing 1 has N micro heat pipe functions. Wherein N is 1 or a natural number more than 1. The manufacturing method adds a heat insulation layer structure 14 and a net-shaped second capillary structure 15 on the other surface of the cavity structure relative to the first capillary structure, which is estimated to reduce the concentration of the surface temperature of the electronic device housing besides increasing the heat dissipation function of the electronic device housing with micro heat conducting pipe function.

Fig. 7A to 7D, fig. 8 and fig. 9A to 9C in the present specification are each an embodiment of the present invention, and the order of the steps of the present invention is not limited. All steps of the present invention can be changed in order with reasonable combination, for example, in fig. 7A, "a first capillary structure is formed on the inner surface of each groove-shaped structure independently" and "a conduit is formed on each groove-shaped structure to match the vent hole, so that the two steps of connecting one end of the conduit to the vent hole" can be changed in order without substantially affecting the meaning of the present invention.

In summary, the method of manufacturing the electronic device casing with micro heat pipe function of the present invention is completed once when manufacturing the electronic device casing or the back cover, and is different from the concept that the existing micro heat pipe and the casing are manufactured separately and then combined to contact. The method is beneficial to an electronic device system designer to keep larger heat dissipation management space application and design flexibility and better heat dissipation efficiency when designing the configuration of the internal parts of the electronic device. The strip-shaped groove on the inner wall of the shell is a part of the pipe wall structure of the micro heat pipe, so that the heat resistance value of a heat dissipation path is further reduced. In addition, the design of the micro heat pipe structure on the electronic device casing and the manufacture of the capillary structure are both beneficial to the efficiency of mass production. Compared with the prior art that the micro-heat pipe and the shell are combined together after being manufactured respectively, the electronic device shell manufactured by the method has a larger internal cavity structure so as to be beneficial to manufacturing of a capillary structure and steam circulation, but the thickness of the whole electronic device body does not need to be increased, and the electronic device product which is thinner and has better heat dissipation technical effect is manufactured. The industrial supply chain for heat dissipating components of electronic devices is further simplified.

The foregoing detailed description of the preferred embodiments is intended to more clearly illustrate the features and concepts of the invention, and not to limit the scope of the invention by the preferred embodiments disclosed above. On the contrary, it is intended to cover various modifications and equivalent arrangements included within the scope of the claims appended hereto. The scope of the claims to be accorded the broadest interpretation in view of the foregoing description so as to encompass all possible variations and equivalent arrangements.

Claims

1. A method for manufacturing an electronic device housing with micro heat pipe function includes:

providing an electronic device shell;

manufacturing N strip-shaped grooves on the inner surface of the electronic device shell to form N groove-shaped structural bodies;

manufacturing N independent groove-shaped structures corresponding to the N groove-shaped structures according to the N strip-shaped grooves, and manufacturing a ventilation hole on each groove-shaped structure;

manufacturing a first capillary structure on the inner surface of each independent groove-shaped structure;

manufacturing a conduit matched with the ventilation hole on each groove-shaped structure, and enabling one end of the conduit to be communicated with the ventilation hole;

hermetically jointing the N groove-shaped structures with the first capillary structure with the corresponding N groove-shaped structures on the inner surface of the electronic device shell so as to form N flat micro heat conducting pipe cavity structures with the first capillary structure on the inner surface of the electronic device shell;

injecting a working fluid into each flat micro-thermal conduit cavity structure on the inner surface of the electronic device casing through the conduit of each groove-shaped structure; and

vacuumizing and sealing the conduit to form N flat micro-heat conduit structures on the inner surface of the electronic device shell so that the electronic device shell has N micro-heat conduit functions;

wherein N is 1 or a natural number more than 1.

2. The method according to claim 1, wherein the first capillary structure is formed on an inner surface of the N groove-shaped structures, and the step of forming a duct in the vent hole extends from an outer surface of the N groove-shaped structures to a direction away from the inner surface of the N groove-shaped structures.

3. The method according to claim 1, wherein the step of forming the first capillary structure on the inner surface of each of the independent trench-shaped structures further comprises applying a slurry on the inner surface of each of the trench-shaped structures by stencil printing, screen printing or spraying and heating the inner surface of the trench-shaped structures to form the first capillary structure.

4. The method according to claim 1, wherein the step of forming the first capillary structure on the inner surface of each of the independent trench-shaped structures further comprises the following sub-steps:

mixing a first soldering tin powder and a second powder with solderability on the surface to form a third powder;

preparing the third powder into a slurry with viscosity and rheological property;

laying the slurry on the weldable inner surface of each of the trench-shaped structures; and

heating the N independent groove-shaped structures to at least the melting point temperature of the first solder powder to form the first capillary structure of each independent groove-shaped structure.

5. The method according to claim 1, wherein the electronic device housing is made of hard materials such as metal, glass or ceramic.

6. The method according to claim 1, wherein the N groove-shaped structures have M heat source contact areas on the outer surface thereof, M is a natural number greater than or equal to 1; when M is equal to 1, the appearance of the flat micro-heat conduit structure is a single strip; when M is larger than 1, the flat micro-heat pipe structure is in a long-head strip shape.

7. The method according to claim 1, wherein the N groove-shaped structures are formed on the inner surface of the electronic device housing by a numerically controlled milling machine.

8. The method according to claim 1, wherein the N groove-shaped structures are bonded to each of the corresponding independent groove-shaped structures by gluing or welding.

9. The method of claim 1, wherein after the step of forming N grooves on the inner surface of the electronic device housing to form N groove-shaped structures, the method further comprises the step of:

a heat insulation layer structure layer is arranged in each groove-shaped structure body to respectively form a heat insulation structure.

10. The method of claim 1, wherein after the step of forming N grooves on the inner surface of the electronic device housing to form N groove-shaped structures, the method further comprises the step of:

a mesh structure layer is arranged in each groove-shaped structure body to respectively form a mesh second capillary structure.

11. The method of claim 1, wherein after the step of forming N grooves on the inner surface of the electronic device housing to form N groove-shaped structures, the method further comprises the steps of:

arranging a heat insulation layer structure layer in each groove-shaped structure body to respectively form a heat insulation structure; and

a mesh structure layer is arranged on the heat insulation layer structure layer in each groove-shaped structure body to form a mesh second capillary structure respectively.