EP3102901A1

EP3102901A1 - Mobile terminal

Info

Publication number: EP3102901A1
Application number: EP14881717.4A
Authority: EP
Inventors: Yongdae Kim; Youngjoo Yee
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 2014-02-04
Filing date: 2014-12-03
Publication date: 2016-12-14
Also published as: CN105940278A; US20160341486A1; WO2015119366A1; KR20150091905A; EP3102901A4

Abstract

A mobile terminal includes: an upper plate; and a lowerplate having a size corresponding to that of the upper plate and having at least a portion spaced apart from the upper plate to form a passage to allow fluid to flow therein, wherein the upper plate and the lower plate form a vapor chamber, at least one of the upper plate and the lower plate is formed by bonding dissimilarmetals, and the passage includes an absorption layer in which a working fluid moves and a vapor channel formed on the absorption layer and allowing vapor evaporated from the absorptionlayer to move therein, and a fluidic channel in which the working fluid moves is formed within the absorption layer.

Description

MOBILE TERMINAL

The present disclosure relates to a mobile terminal and, more particularly, to a mobile terminal in which an existing magnesium (Mg) frame is substituted with a vapor chamber that outwardly dissipates heat from a heating element within the mobile terminal.

In general, a heat pipe serves to outwardly transmit heat from a heating element, among large components such as a PC server, a combined heat and power generator, and the like, to prevent overheating.

FIG. 1 is a view illustrating an operation principle of a general heat pipe 10. Referring to FIG. 1, the heat pipe 10 includes an exterior 11 formed of a material having excellent heat transmission performance and an absorption layer 12 formed on inner walls of the exterior 11. A fluidic channel through which a working fluid 25 flows is formed within the absorption layer 12.

The heat pipe 10 serves to diffuse or transmit heat energy. As for major processes of an operation, first, evaporation 22 occurs by heat 21 transmitted from a heating element 20 having a heat source, the evaporated steam 25 flows in a vapor channel 26, steam 23 is condensed in the vapor channel 26 and a condenser 40 and subsequently converted into a liquid 24 to flow in the absorption layer 12 (a liquid channel or wick).

Namely, the liquid 24 undergoes a circulation process in which, the liquid 24 is converted into vapor 22 in the heating element 30, and while passing through the vapor channel 26, the vapor 22 is deprived of heat in a condensing unit 40 so as to be changed to liquid 24, and the liquid 24 is returned to its initial position along the absorption layer 12.

The absorption layer 12 in which the condensed liquid flows may be formed of a materialidentical to that of the heat pipe 10. If the heat pipe 10 is formed of a heterogeneous material, a galvanic corrosion phenomenon may occur in an interface between a working fluid and the heat pipe 10 to degrade reliability of the heat pipe 10 as a heat dissipation element, significantly reducing thermal conductivity.

Research into a heat dissipation structure of heat pipes has actively conducted, and thus, materials of heat pipes that may be compatible with types of working fluids have been systematically classified and used according to requirements of various application fields in the industry.

The application fields of the heat pipes are extensive in the industry, and in many cases, heat pipes are manufactured such that the absorption layer 12 is present in a cylindrical edge thereof.

Recently, as mobile terminals including smartphones implement various functions required in all aspects of daily lives, such as Internet, games, mobile payment, music, video, and the like, beyond the simple voice call function, performance and integration of application processor (AP) chips have explosively increased, and thus, heating of AP chips is a serious problem. Heating is not limited to AP chips but significantly increases power consumption of chips, resulting in fast discharge of batteries, and for users, a surface of a mobile terminal is hot to cause user inconvenience, and in a worst case scenario, the risk of burns is increasing.

In order to dissipate heat from an AP chip used in a mobile terminal, conventionally, a graphite sheet is used. Also, in order to secure strength, a frame is formed of a metal such as magnesium, or the like, and assembled with a heating unit to provide a heat dissipation function. However, the graphite sheet itself has excellent heat dissipation characteristics, but due to the very low heat dissipation characteristics of the frame formed of a metal, the heat characteristics of the graphite and the frame are averaged, resulting in that a reduction in the heating of the AP chip is not greatly improved overall.

Also, although an existing heat pipe has excellent thermal conductivity, there is a limitation in the strength and thickness, and thus, the use of existing heat pipes is limited.

Therefore, an aspect of the detailed description is to providea vapor chamber capable of maintaining rigidity, while maintaining excellent thermal conductivity.

Another aspect of the detailed description is to provide a mobile terminal in which a heat dissipation module (graphite sheet + frame) is substituted with a single heat dissipation element, thus simplifying the structure.

Another aspect of the detailed description is to provide a mobile terminal in which a vapor chamber having excellent heat dissipation characteristics is used as a frame.

To achieve these and other advantages and in accordance with the purpose of this specification, as embodied and broadly described herein, a mobile terminal may include: a front case; a rear case covering the opposite surface of the front case; and a frame supporting an electrical element formed between the front case and the rear case, wherein the frame includes: an upper plate; and a lower plate having a size corresponding to that of the upper plate and having at least a portion spaced apart from the upper plate to form a passage to allow fluid to flow therein, wherein the upper plate and the lower plate form a vapor chamber, at least one of the upper plate and the lower plate is formed by bonding dissimilar metals, and the passage includes an absorption layer in which a working fluid moves and a vapor channel formed on the absorption layer and allowing vapor evaporated from the absorption layer to move therein, and a fluidic channel in which the working fluid moves is formed within the absorption layer.

The absorption layer may be formed of a porous material, and a first metal among the dissimilar metals may be one or more selected from the group consisting of copper, aluminum, an aluminum alloy, nickel, a nickel alloy, titanium, and magnesium.

A second metal among the dissimilar metals may be stainless steel. The first metal may form an appearance of the vapor chamber, and the second metal may be formed within thevapor chamber. The first metal may have two or more layers formed by combining two or more selected from the group consisting of copper, aluminum, an aluminum alloy, nickel, a nickel alloy, titanium, and magnesium.

The upper plate may have a convex portion and a concave portion to form the passage, and the upper plate and the lower plate may be bonded by welding or diffusion bonding.

A heat dissipation element may be coupled to the concave portion, and the lower plate may have a flat plate shape.

The absorptionlayer may include a first layer formed by growing grains and a second layer formed on the first layer and including a plurality of acicular particles.

The vapor chamber may be coupled to the rear case or the front case.

According to at least one exemplary embodiment, since the vapor chamber is advantageous in the aspect of thickness and rigidity, while maintaining excellent thermal conductivity, it can replace a heat dissipation sheet and a corresponding frame of a mobile terminal, simplifying the structure.

Also, by maximizing utilization in products of a display field having a thin structure, such as a digital TV, an advertisement display, a notebook computer, a tablet, a netbook, and the like, the vapor chamber can lower a heating temperature of a product according to high density integration and implement highly efficient product.

In addition, according to an exemplary embodiment of the present disclosure, the structure of the ultra-slim vapor chamber serves as a heat pipe lowering a temperature of a heating portion by transmitting heat from the heating portion to a low-temperature region, and also serves as a frame for strengthening rigidity of a heat dissipation element by applying a clad metal formed by bonding dissimilar metals and fixing other components of the mobile terminal.

Further scope of applicability of the present application will become more apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from the detailed description.

FIG. 1 is a view illustrating an operation principle of a related art heat pipe.

FIG. 2 is a plan view of a vapor chamber according to an exemplary embodiment of the present disclosure.

FIG. 3 is a cross-sectional view of the vapor chamber according to an exemplary embodiment of the present disclosure.

FIG. 4 is a view illustrating a process of manufacturing a vapor chamber according to an exemplary embodiment of the present disclosure.

FIG. 5 is an exploded perspective view of a mobile terminal using a vapor chamber according to an exemplary embodiment of the present disclosure.

FIG. 6 is a cross-sectional view of a mobile terminal using a vapor chamber according to an exemplary embodiment of the present disclosure.

FIG. 7 is a cross-sectional view taken along line B-B' of FIG. 3.

Hereinafter, the embodiments of the present invention will be described with reference to the accompanying drawings, in which like numbers refer to like elements throughout although the embodiments are different, and a description of the like elements a first embodiment will be used for those of the different embodiment. In the following description, usage of suffixes such as 'module', 'part' or 'unit' used for referring to elements is given merely to facilitate explanation of the present invention, without having any significant meaning by itself. In describing the present invention, if a detailedexplanation for a related known function or construction is considered to unnecessarily divert the gist of the present invention, such explanation has been omitted but would be understood by those skilled in the art. The accompanying drawings of the present invention aim to facilitate understanding of the present invention and should not be construed as limited to the accompanying drawings. Also, the present invention is not limited to a specific disclosed form, but includes all modifications, equivalents,and substitutions without departing from the scope and spirit of the present invention.

It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another.

As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It will be further understood that the terms "comprises" "comprising," "includes" and/or "including" when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof.

The present disclosure relates to a heat dissipation element, which also referred to as a chamber, as a type of heat pipe. In particular, the present disclosure relates to an ultra-slim vapor chamber that can be applied to various products in the form of a heat pipe. In an exemplary embodiment of the present disclosure, a material and a structure for complementing a degradation of rigidity according to the ultra-slim structure are provided.

Namely, the present disclosure relates to an ultra-slim vapor chamber 100 which solves a heating problem of a mobile terminal based on the excellent heat conductivity and an operational principle of an existing heat pipe and plays a role of a frame of an electronic component.

The mobile terminal described in the present disclosure may include a cellular phone, a smartphone, a notebook computer (or a laptop computer), a digital broadcasting terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation device, a slate PC, a tablet PC, an ultrabook, a wearable device (e.g., a watch-type terminal such as smartwatch, a glass-type terminal such as smart glass, a head mounted display(HMD), and the like.

However, it will be obvious to those skilled in the art that the present disclosure may also be applicable to a fixed terminal such as a digital TV, a desktop computer and a digital signage, except for specific configurations for mobility.

In an exemplary embodiment of the present disclosure, copper (Cu), which has excellent thermal conductivity, relative to other metals, and is not chemically reacted with a working fluid (water) within the heat pipe, is used as a material to form an appearance of the vapor chamber 100. However, copper (Cu) has high ductility as inherent properties, and thus, its application to mobile terminal fields that require rigidity and heat dissipation performance is very limited in spite of the excellent heat dissipation characteristics thereof.

In an exemplary embodiment of the present disclosure, the shortcomings are complemented, excellent heat dissipation characteristics and rigidity are secured, and the entire area of a mobile terminal is covered by a ultra-slim vapor chamber 100, thus obtaining aheat dissipation effect.

According to an exemplary embodiment of the present disclosure, the ultra-slim vapor chamber 100 may be customized to be applied to mobile terminals having various structures.

FIG. 2 is a view illustrating a structure of the ultra-slim vapor chamber 100according to an exemplary embodiment of the present disclosure, and FIG. 3 includes a partial plan view of the vapor chamber 100 of FIG. 2, a cross-sectional view taken along line A-A', and a partially enlarged view of a portion. FIG. 7 is a cross-sectional view taken along line B-B' of FIG. 3.

First, referring to FIGS. 2 and 3, the vapor chamber 100 includes an upper plate 111 and a lower plate 112 spaced apart from the upper plate 111 in at least a portion thereof, to form a passage 113 in which a fluidsuch as a liquid or vapor moves. Here, at least one of the upper plate 111 and the lower plate 112 is formed of a clad metal formed by bonding dissimilar metals.

The upper plate111 includes a convex portion 111c and concave portions 130 and 140 formed through pressing, or the like. The passage 113 is formed by the convex portion 111c and the concave portions 130 and 140.

Here, the passage 113 includes an absorption layer 113a in which a liquid is fixedly stored by capillary force, a fluidic channel in which a working fluid moves is formed within the absorption layer 113a, and a vapor-condensed fluid moves through the fluidic channel 113c. Here, the working fluid largely refers to a liquid.

Also, as illustrated in FIG. 7, a vapor channel 113b in which vapor evaporated from the absorption layer 113a moves is formed on the absorption layer 113a. The absorption layer 113a and the vapor channel 113b are formed in the same space, and the vapor channel 113b is a channel in which a liquid (e.g., water) heated by a heating element is evaporated to become vapor and subsequently move to a condensing portion (e.g., one end portion of the vapor chamber).

The absorption layer 113a is formed of a porous material, preventing a fluid such as water from being leaked out. Namely, water is stored in the absorption layer 113a due to a capillary force phenomenon.

In detail, the absorption layer 113a includes a plurality of acicular particles and a working fluid moves between the plurality of acicular particles, namely, to pores. In detail, as illustrated in the enlarged view of FIG. 3, the absorption layer 113a includes a first layer formed by grain growth and a second layer 1132 formed on the first layer 1131 and including a plurality of acicular particles. The fluidic channel 113c in which a fluid is movable is formed betweenthe acicular particles. Here, the second layer 1132 is thicker than the first layer 1131, and preferably, the thickness of the second layer 1132 is ten times to 30 times that of the first layer 1131.

The first layer 1131 is an underlayer forming conditions facilitating formation of the second layer 1132 having a plurality of acicular particles. The first layer 1131 is formed through an electroplating method in which a current having a DC waveform supplying a DC current in a reverse (-) direction. The second layer 1132 has a plurality of acicular particles. The second layer 1132 is also formed through the electroplating method, specifically, through a periodic reverse current plating performed by periodically changing a direction of an electriccurrent or by using a bipolar pulse current. Here, a length of the plurality of acicular particles forming the second layer 1132 in a longer direction ranges from 10 m to 50 m.

In this manner, the second layer 1132 according to an exemplary embodiment of the present disclosure includes the acicular particles, specifically, acicular copper particles, and thus, the second layer 1132 has high porosity, compared with the related art absorption layer in the form of a groove or a mesh, or a sintered absorption layer. Thus, a working fluid may smoothly move within the absorption layer 113a, relative to the related art, enhancing a heat-exchange rate or heat-exchange performance.

Here, the vapor chamber 100 includes a path formation region 110 in which vapor or a liquid may flow and an edge 120 formed outside of the path formation region 110. Since the lower plate 112 has a flat plate shape, the vapor chamber 100 has a flat plate shape overall.

Here, only any one of the upper plate 111 and the lower plate 112 may be a clad metal, and in an exemplary embodiment of the present disclosure, both the upper plate 111 and the lower plate 112 are formed of a clad metal formed by bonding dissimilar metals.

In detail, the ultra-slim vapor chamber 100 according to an exemplary embodiment of the present disclosure is formed of a metal, and here, a clad metal formed by bonding dissimilar metals is used. A structure of the clad metal may include copper (Cu) and stainless steel (SUS). However, besides the foregoing copper (Cu)/stainless steel (SUS), various metals having high rigidity may also be used. Namely, composition of the clad metal may be altered according to requirements of specific application purposes to form the vapor chamber 100.

When the upper plate 111 or the lower plate 112 are formed of a clad metal formed by bonding dissimilar metals, metals 111b and 112a exposed inwardly may be formed of oxygen-free copper (Cu) having high ductility and externalmetals 111a and 112b may be formed of materials having high rigidity such as stainless steels.

Here, besides stainless steel, the metals 111a and 112b exposed to outside may be one or more selected from the group consisting of copper, aluminum, an aluminum alloy, nickel, a nickel alloy, titanium, and magnesium, or may be formed of two or more layers by combining these elements.

For example, the metal 111a may be formed of only stainless steel or may have an aluminum alloy in the outermost portion. This may be the same for the metals 111b and 112a formed internally. Here, the metals 111a and 112b are described as stainless steel, but the present disclosure is not limited thereto and any metal may be used as long as it has rigidity equivalent to that of stainless steel.

Also, when the metals 111a and 112b exposed outwardly are a first metal, and the internal metals 111b and 112a are a second metal, the second metal may be formed of copper, aluminum, an aluminum alloy, nickel, a nickel alloy, titanium, magnesium, and the like, and the first metal may be formed of stainless steel. Or conversely, the first metal may be formed of copper, aluminum, an aluminum alloy, nickel, a nickel alloy, titanium, magnesium, and thelike, and the second metal may be formed of stainless steel.

Also, the lower plate 112 may simply be a flat clad metal, and the overall thickness of the vapor chamber 100 may be 0.5 mm. Here, a vapor inlet 150 may be provided in a portion of the edge 120 to allow a liquid (water) to be injected to the interior of the chamber 100 therethrough.

Meanwhile, in an exemplary embodiment of the present disclosure, portions of the upper plate 111 and the lower plate 112 are in contact to form concave portions 130 and 140. The concave portions 130 and 140 support the fluidic channel 113 and serve as a post maintaining rigidity of the structure to prevent bending due to external impact. The concave portions 130 and 140 may be patterned through metal forming. As illustrated in FIGS. 2 and 3, thepath formation region 110 part protrudes to form a space, and the upper plate 111 and the lower plate 112 are formed of clad metal. The concave portion 130 may be a rib, and the concave portion 140 may be a portion in which a heating element such as a CPU is fixed.

In the concave portions 130 and 140, as the upper plate 111 and the lower plate 112 are compressed, a path 113 having a corrugation shape may be formed. Here, the upper plate 111 and the lower plate 112 may be bonded through welding or diffusion bonding. Namely, in an exemplary embodiment of the present disclosure, the fluid movement passage 113 is etched or a flow path pattern having a corrugation shape is formed by sheet metal working, or the like, to allow vapor to circulate between the upper plate 111 and the lower plate 112 after the evaporation in the heating unit.

As discussed above, when the passage 113 has a corrugation shape in the upper plate 111 or the lower plate 112 of the ultra-slim vapor chamber 100 according to an exemplary embodiment of the present disclosure, a channel wall of the passage 113 serves as a support with respect to external force and rigiditycan be strengthened. Also, in the ultra-slim vapor chamber 100, the upper plate 111 and the lower plate 112 including the vapor channel corrugation are bonded in a surface-to-surface manner without using a heterogeneous adhesive material. Namely, the upper plate 111 and the lower plate 112 can be assembled through a bonding technique such as diffusion bonding, local welding, or the like, which fundamentally preventing a chemical reaction and corrosion between the fluid and the material. In addition, a process of bonding the upper plate111 and the lower plate 112 by utilizing a laser welding technique, as well as the diffusion bonding, may also be additionally performed.

FIG. 4 is a view illustrating a process of manufacturing the vapor chamber 100 according to an exemplary embodiment of the present disclosure. Referring to FIG. 4, the upper plate 111 formed as a clad metal (please refer to FIG. 4A) by bonding dissimilar metals 111a and 111b is pressed by using a press tool 160 at high pressure so as to be processed to have an embossed structure (please refer to FIG. 4B) to have a shape corresponding to a curved surface160a of thepress tool 160. Accordingly, an inner surface of the upper plate 111 has a shape corresponding to the curved surface 160a, and the convex portion111c protruding upwardly is formed.

FIG. 4C illustrates the ultra-slim vapor chamber 100 having high rigidity characteristics completed by bonding the upper plate 111 having the embossed structure with the concave portions 130 and 140 and the convex portion111c and the lower plate 112 having a flat structure through welding. Here, the lower plate 112 is also formed by bonding dissimilar metals 112a and 112b. The metal 112a positioned within the vapor chamber 100 may be formed of the same material as that of the metal 111b positioned within the upper plate 111, and the metal 112b positioned outside of the vapor chamber 110 may be formed of the same material as that of the metal 111a positioned outside of the upper plate 111. A hollow portion 117 (please refer to FIG. 4D) is formed by bonding the upper plate 111 and the lower plate 112, and the passage 113 may be provided in the hollow portion 117 (please refer to FIG. 4E).

As described above, in an exemplary embodiment of the present disclosure, the structureand manufacturing method capable of enhancing the rigidity characteristicsof the ultra-slim vapor chamber 100 are provided, a heating problem is solved, and a frame structure providing a function of protecting an electronic component of the mobile terminal from external force, and the like, is provided.

Also, the structure of the vapor channel 110 of the ultra-slim vapor chamber 100 according to an exemplary embodiment of the present disclosure can be configured to have various shapes to provide an electrical ground plane as well as being a heat dissipation element.

Hereinafter, utilization of a vapor chamber according to an exemplary embodiment of the present disclosure in a mobile terminal will be described.

FIG. 5 is an exploded perspective view of a mobile terminal using a vapor chamber according to an exemplary embodiment of the present disclosureas a frame of the mobile terminal, and FIG. 6 is a cross-sectional view of a mobile terminal using a vapor chamber according to an exemplary embodiment of the present disclosure as a frame.Here, FIG. 6 may be a cross-sectional view of FIG. 5.

Referring to FIGS. 5 and 6, a mobile terminal 200 according to an exemplary embodiment of the present disclosure has a bar-type terminal body. However, the present disclosure is not limited thereto and may be applied to a slide type mobile terminal, a folder type mobile terminal, or a swing type mobile terminal, and the like, in which two or more bodies are coupled to each other so as to perform a relative motion. Further, the mobile terminal described in the present disclosure may be applied to any portable electronic device having a camera and a flash, for instance, a portable phone, a smart phone, a notebook computer, a digital broadcasting terminal, Personal Digital Assistants (PDAs), Portable Multimedia Players (PMO), etc.

The terminal body may include a case (which may also be referred to as a casing, a housing, a cover, etc.) which forms the appearance of the mobile terminal. The case may include a front case 201, a rear case 202 covering the opposite side of the front case 201, and a battery cover 203 for coupled to the rear case 202 to form a rear surface of the mobile terminal 200. A space formed by the front case 201 and the rear case 202 may accommodate various electrical elements 260 such as an application processor (AP), or the like. Such cases may be formed by injection-molding a synthetic resin, or may be formed using a metallic material such as stainless steel (STS) or titanium (Ti).

The electronic componentssuch as the AP, or the like, generates a great amount of heat, and thus, heat of the electronic components need to be promptly dissipated to ensure a reliable operation without malfunction.

The mobile terminal200 includes a window 210 and a displaymodule 220 coupled to one surface of the front case 201. The front case 201 and the rear case 202 form an appearance of the mobile terminal200, and a frame is formed to support electrical elements 260 between the front case 201 and the rear case 202. The frame is an internal support structure of the mobile terminal 200. For example, the frame may be formed to support at least any one among the displaymodule 220, a camera module, an antenna device 242, or a printed circuit board (PCB) 250. Here, however, in FIG. 5, it is illustrated that the frame supports the PCB 250 and the battery 230.

According to an exemplary embodiment of the present disclosure, the frame is the foregoing vapor chamber 100, and a portion of the vapor chamber 100 may be exposed to outside of the terminal. Also, the vapor chamber 100 may form a portion of a sliding module connecting a terminal body and a display unit in a slide-type mobile terminal, rather than a bar-type terminal.

In FIG. 5, for example, it is illustrated that the PCB 250 is disposed between the vapor chamber 100 and the rear case 202 and the display module 220 is coupled to one surface of the vapor chamber 100. The PCB 250 and the battery 250 may be disposed on the other surface of the vapor chamber 100, and the battery cover 203 may be coupled to the rear case 202 to cover the battery 230.

The window 210 is coupled to one surface of the front case 201. A touch sensor (not shown) may be installed in the window 210. The display module 220 is installed on a rear surface of the window 210. In this embodiment, a thin film transistor-liquid crystal display (TFT-LCD) is provided as an example of the display module 220, but the present disclosure is not limited thereto.

For example, the display module 220 may be a liquid crystal display (LCD), an organic light emitting diode (OLED) display, a flexible display, a three-dimensional (3D) display, or the like.

As described above, the PCB 250 may be formed on one surface of the vapor chamber 100, or it may also be installed below the display module 220. At least one electrical element 260 is installed on a lower surface of the PCB 250.

The rear case 202 may have a battery accommodation portion recessed to accommodate the battery 230. A contact terminal may be formed on one surface of the battery accommodation portion and connected to the PCB 250 to allow the battery 230 to supply power to the terminal body.

The antenna device 242 may be formed on upper end or a lower end of the mobile terminal 200. Also, a plurality of terminal devices 242 may be formed and disposed at each end portion of the mobile terminal 200, and here, the antenna devices 242 may be formed to transmit and receive wireless signals having different frequency bands.

The vapor chamber 100 may be formed of a clad metal as described above in order to maintain sufficient rigidity even though it is formed to have a small thickness. Here, the vapor chamber 100 may operate as a ground. Namely, the PCB 250 or the antenna device 242 may be ground-connected to the vapor chamber 100, and the vapor chamber 100 may operate as a ground of the PCB 250 or the antenna device 242. In this case, the vapor chamber 100 may extend a ground of the mobile terminal 200.

The vapor chamber 100 and the rear case 202 may be coupled by a screw 270. The PCB 250 may be disposed between the vapor chamber 100 and the screw 270. When the vapor chamber 100 is coupled to the screw 270, the screw 270 may be exposed outwardly from the terminal body, such that static electricity within the terminal may be released outwardly. Also, when the vapor chamber 100 operates as a ground, the ground of the terminal may extend by coupling the vapor chamber 100 and the screw 270. In this case, the screw 270 may also be coupled to any other conductive member.

The rear case 202, the PCB 250, and the vapor chamber 100 may respectively have through holes 271, 272, and 273 in portions coupled to the screw 270. The through holes 271, 272, and 273 may be formed on the edges of the terminal body or may be formed in a central region thereof. In the above, the vapor chamber 100 is coupled to the rear case 202, but the present disclosure is not limited thereto and the vapor chamber 100 may also be coupled to the front case 201.

In the above, it is described that the vapor chamber 100, the PCB 250, and the rear case 202 are coupled by the screw 270, but the present disclosure is not limited thereto and the vapor chamber 100, the PCB 250, and the rear case 202 may also be coupled by a hook, an adhesive, or the like.

Hereinafter, a process of dissipating heat according to an exemplary embodiment of the present disclosure will be described with reference to FIG. 6.

FIG. 6 is a cross-sectional view of the mobile terminal 200 having the vapor chamber 100. When the electrical element 260, a heating element, formed on the PCB 250 generates heat, heat 2252 may flow to the PCB 250 in contact with the electrical element 260, and the heat 2253 flowing along the PCB 250 may move toward the vapor chamber 100 and move along the vapor chamber so as to be dissipated outwardly.

Here, a partial amount 2251 of the heat generated by the electrical element 260 may also be discharged outwardly through the PCB 250, the rear case 202, and the battery cover 203.

However, most heat 225 generated by the electrical element 260 moves outwardly through the vapor chamber 100.

Here, a movement path of the heat 225 within the vapor chamber 100 is similar to that described above. Namely, evaporation occurs due to the heat 225 transmitted from the electrical element 260, evaporated vapor flows in the vapor channel 113b, steam is condensed in the condensing unit so as to be converted into a liquid form, and the liquid may flow to the absorption layer 113a (liquid channel or wick).

This has been described with reference to FIG. 1, so a detailed description thereof will be omitted.

The exemplary embodiment of the present disclosure may be utilized in a vapor chamber that transmits heat from a heat dissipation element to outside.

The foregoing embodiments and advantages are merely exemplary and are not to be considered as limiting the present disclosure. The present teachings can be readily applied to other types of apparatuses. This description is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. The features, structures, methods, and other characteristics of the exemplary embodiments described herein may be combined in various ways to obtain additional and/or alternative exemplary embodiments.

As the present features may be embodied in several forms without departing from the characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be considered broadly within its scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalents of such metes and bounds are therefore intended to be embraced by the appended claims.

The embodiment of the invention may be applied to a mobile terminal using a vapor chamber that outwardly dissipates heat from a heating element within the mobile terminal.

Claims

A mobile terminalcomprising:

a front case;

a rear case covering the opposite surface of the front case; and

a frame supporting an electricalelement formed between the front case and the rear case,

wherein the frame comprises:

an upper plate; and

a lowerplate having a size corresponding to that of the upper plate and having at least a portion spaced apart from the upper plate to form a passage to allow fluid to flow therein,

wherein the upper plate and the lower plate form a vapor chamber, at least one of the upper plate and the lower plate is formed by bonding dissimilar metals, and the passage includes an absorption layer in which a working fluid moves and a vapor channel formed on the absorption layer and allowing vapor evaporated from the absorptionlayer to move therein, and a fluidic channel in which the working fluid moves is formed within the absorption layer.
The mobile terminal of claim 1, wherein the absorption layer is formed of a porous material.
The mobile terminal of claim 2, wherein a first metal among the dissimilar metals is stainless steel.
The mobile terminal of claim 3, wherein a second metal among the dissimilar metals is one or more selected from the group consisting of copper, aluminum, an aluminum alloy, nickel, a nickel alloy, titanium, and magnesium.
The mobile terminal of claim 4, wherein the first metal forms an appearance of the vapor chamber, and the second metal isformed within the vapor chamber.
The mobile terminal of claim 4, wherein the second metal hastwo or more layers formed by combining two or more selected from the group consisting of copper, aluminum, an aluminum alloy, nickel, a nickel alloy, titanium, and magnesium.
The mobile terminal of claim 6, wherein the upper plate hasa convex portion and a concave portion to form the passage.
The mobile terminal of claim 1, wherein the upper plate and the lower plate are bonded by welding or diffusion bonding.
The mobile terminal of claim 7, wherein a heat dissipation element is coupled to the concave portion.
The mobile terminal of claim 1, wherein the lower plate has a flat plate shape.
The mobile terminal of claim 2, wherein the absorption layer comprises:

a first layer formed by growing grains and

a second layer formed on thefirst layer and including a plurality of acicular particles.
The mobile terminal of claim 1, wherein the vapor chamber is coupled to the rear case or the front case.