JP7541570B2 - Mobile devices - Google Patents

Description

The present invention relates to a mobile terminal.

In mobile terminals such as smartphones, various electronic components are mounted inside the housing. Various technologies have been proposed to diffuse the heat generated by these electronic components. For example, Patent Document 1 describes a mobile terminal in which a rechargeable battery is attached to a metal frame with thermally conductive double-sided tape. Patent Document 2 describes a liquid crystal display device for projectors in which a liquid crystal panel is fixed to a metal plate with highly thermally conductive double-sided tape.

JP 2014-029918 A JP 2005-062726 A

As mobile terminals become smaller and thinner and have larger display screens, the space available for mounting various components such as electronic components and circuit boards housed within the housing is on the decline. Furthermore, in the fifth generation mobile communication system (hereinafter also referred to as 5G), which is defined as the next communication standard in the Third Generation Partnership Project (3GPP), the amount of heat generated by electronic components during communication will be significantly greater than before. In such a situation, it has become difficult to disperse the heat generated by electronic components within the housing, making it easier for heat spots (areas that become partially very hot) to occur.

One aspect of the disclosed technology aims to provide a mobile terminal that is easily thin and can easily control the conduction of heat from heat-generating components.

One aspect of the disclosed technology is exemplified by the following mobile terminal. This mobile terminal comprises a heat-generating component, a vapor chamber containing a heat-transporting fluid and having a main body in contact with the heat-generating component and a protrusion protruding from the edge of the bottom of the main body, a plate-shaped metal structure having a through hole into which the main body is inserted, and a thermally conductive adhesive member that adheres the protrusion, which is positioned so as to overlap the metal structure when viewed in the normal direction of the metal structure, to the metal structure, a gap is formed between the main body and the metal structure, and the thermally conductive adhesive member is positioned according to the amount of heat to be conducted from the heat-generating component to the metal structure.

The disclosed technology can be easily made thin and easily control the conduction of heat from heat-generating components.

FIG. 1 is an exploded perspective view of a smartphone according to an embodiment. FIG. 2 is a cross-sectional view taken along line AA of FIG. FIG. 3 is a diagram illustrating a state in which the rear cover of the smartphone according to the embodiment is removed. FIG. 4 is an end view taken along line BB of FIG. FIG. 5 is a diagram illustrating the conduction of heat from a vapor chamber to a heat sink in the embodiment. FIG. 6 is a diagram illustrating the transfer of heat from an electronic component to a heat sink via a vapor chamber in an embodiment. FIG. 7 is a first diagram showing a schematic diagram of a difference in thermal conductivity due to differences in width of a thermally conductive double-sided tape. FIG. 8 is a second diagram showing a schematic diagram of the difference in thermal conduction due to the difference in width of the thermally conductive double-sided tape.

<Embodiment>
The configurations of the embodiments described below are merely examples, and the disclosed technology is not limited to the configurations of the embodiments. A mobile terminal according to the embodiments has, for example, the following configuration.
The mobile terminal according to this embodiment is
A heat generating component;
a vapor chamber that contains a heat transporting fluid and has a main body that contacts the heat generating component and a protrusion that protrudes from an edge of a bottom of the main body;
a plate-shaped metal structure having a through hole into which the main body is inserted;
a thermally conductive adhesive member that adheres the protrusion that is arranged to overlap the metal structure when viewed in a normal direction of the metal structure to the metal structure,
A gap is formed between the main body and the metal structure,
The thermally conductive adhesive members are positioned according to the amount of heat to be conducted from the heat generating component to the metal structure.

The mobile terminal according to the embodiment is a portable information processing device that can be carried by a user. Examples of portable information processing devices include feature phones, smartphones, tablet computers, wearable computers, and notebook computers.

Heat-generating components are components in a mobile terminal that generate heat. Examples of heat-generating components include processors, memories, secondary batteries, and antenna devices.

The vapor chamber is a heat pipe in which both the main body and the protruding portion are formed in a flat shape using a thin metal plate. The vapor chamber is formed thinner than conventional heat pipes. The vapor chamber has a space for enclosing a fluid that transports heat, so the main body is thicker than the protruding portion. If a main body having such a thickness is placed on the metal structure in order to conduct heat from the vapor chamber to the metal structure, it becomes difficult to make the mobile terminal thinner. Therefore, in this embodiment, the main body is inserted into a through hole provided in the plate-shaped metal structure. Then, the protruding portion protruding from the edge of the bottom of the main body is placed so as to overlap the metal structure when viewed in the normal direction of the metal structure, and the protruding portion and the metal structure are bonded with a thermally conductive adhesive material, thereby realizing heat conduction from the vapor chamber to the metal structure. By inserting the thick main body into the through hole of the metal structure, it is possible to easily make the mobile terminal thinner.

Because the metal structure is made of metal, it has high thermal conductivity and can easily diffuse heat conducted from the vapor chamber. In this embodiment, the metal structure may be in contact with the inner wall surface of the housing of the mobile terminal. By contacting the inner wall surface of the housing, the metal structure can support the housing from the inside. This increases the rigidity of the mobile terminal.

Here, various materials can be used as the thermally conductive adhesive member as long as they have high thermal conductivity and can bond the protrusion and the metal structure. The thermally conductive adhesive member may be, for example, a double-sided tape with high thermal conductivity or an adhesive with high thermal conductivity. The thermally conductive adhesive member may also be a member with high thermal conductivity that welds the protrusion and the metal structure.

Furthermore, in this embodiment, the amount of heat conducted from the heat generating component to the metal structure can be controlled by the arrangement of the heat conductive adhesive member that bonds the protrusion and the metal structure. For example, in a portion where it is desired to conduct more heat from the heat generating component to the metal structure, the protrusion and the metal structure can be bonded with a heat conductive adhesive member formed with a wide width or a heat conductive adhesive member with high thermal conductivity. Also, for example, in a portion where it is desired to suppress the heat conducted from the heat generating component to the metal structure, the protrusion and the metal structure can be bonded with a heat conductive adhesive member formed with a narrow width or a heat conductive adhesive member with low thermal conductivity, or bonding with a heat conductive adhesive member can be omitted. The arrangement of the heat conductive adhesive member makes it possible to control the amount of heat conducted from the heat generating component to the metal structure.

Here, the thermally conductive adhesive member may be arranged with a first width in a portion that promotes the conduction of heat from the heat-generating component, and with a second width wider than the first width in a portion that suppresses the conduction of heat from the heat-generating component.

In the mobile terminal according to this embodiment, the vapor chamber may be in contact with the heat-generating component in a portion of the main body. In other words, at least a portion of the vapor chamber is not in contact with the heat-generating component. By providing such a feature, the vapor chamber can easily conduct heat from the heat-generating component to an area where the heat-generating component is not mounted.

Below, an embodiment in which the above-mentioned mobile terminal is applied to a smartphone will be further described with reference to the drawings. FIG. 1 is an exploded perspective view of a smartphone according to an embodiment. Smartphone 1 is a portable information processing device capable of wireless communication. Smartphone 1 comprises a front cover 11, a vapor chamber 12, a thermally conductive double-sided tape 13, a heat sink 14, a substrate 15, and a rear cover 16.

Smartphone 1 is a portable information processing device. Front cover 11 and rear cover 16 form the housing of smartphone 1. Front cover 11 is equipped with, for example, a display, a speaker, and a microphone. Rear cover 16 is equipped with, for example, a rear camera. In smartphone 1, a vapor chamber 12, thermally conductive double-sided tape 13, a heat sink 14, and a substrate 15 are housed within the housing formed by front cover 11 and rear cover 16.

The vapor chamber 12 is a heat pipe formed into a thin plate shape. Figure 2 is a cross-sectional view taken along line A-A in Figure 1. Figure 2 shows a schematic cross-section of the vapor chamber 12. As can be seen by referring to Figure 2, the vapor chamber 12 comprises a main body portion 121 and a protruding plate 122. The vapor chamber 12 is an example of a "vapor chamber".

The main body 121 is filled with a fluid that transports heat. The fluid is, for example, pure water. As can be understood by referring to FIG. 2, the vapor chamber 12 used in the embodiment includes an upper plate 1211 having a generally U-shaped cross-sectional view that opens downward, a flat bottom plate 1212 that closes the opening, and a protruding plate 122 that protrudes from the end of the bottom plate 1212 in the width direction. The bottom plate 1212 and the protruding plate 122 may be formed integrally or separately. The fluid is sealed in an internal region 1213 defined by the upper plate 1211 and the bottom plate 1212. A wick is provided in the internal region 1213 for transporting heat by the fluid. The main body 121 is thicker than the protruding plate 122 in order to seal the fluid in the internal region 1213. The main body 121 is an example of a "main body". The protruding plate 122 is an example of a "protruding part".

The thermally conductive double-sided tape 13 is a double-sided tape made of a material with high thermal conductivity. In this embodiment, the heat sink 14 and the protruding plate 122 of the vapor chamber 12 are bonded with the thermally conductive double-sided tape 13. The thermally conductive double-sided tape 13 then conducts the heat transported by the vapor chamber 12 to the heat sink 14. The thermally conductive double-sided tape 13 is an example of a "thermally conductive adhesive member."

The heat sink 14 is a plate-shaped member made of metal with high thermal conductivity. The heat sink 14 is housed in a housing formed by the front cover 11 and the rear cover 16. In other words, the heat sink 14 is disposed between the front cover 11 and the rear cover 16 in the thickness direction of the smartphone 1.

The heat sink 14 is formed with a through hole 141 that penetrates the heat sink 14 in the thickness direction. The through hole 141 is formed in a shape that allows the main body 121 of the vapor chamber 12 to be inserted. The through hole 141 preferably has a central portion 1411 that passes near the center of the heat sink 14, as exemplified in FIG. 1. By adopting a vapor chamber 12 that conforms to a shape in which the through hole 141 passes near the center of the heat sink 14 in this way, it becomes easy to conduct heat from the vapor chamber 12 to the center of the heat sink 14 and efficiently diffuse the conducted heat throughout the heat sink 14. The heat sink 14 is an example of a "metal structure". The through hole 141 is an example of a "through hole".

The substrate 15 is a substrate on which the electronic component 151 is mounted. The substrate 15 is, for example, a printed circuit board. Examples of the electronic component 151 include a central processing unit (CPU) and a memory. The electronic component 151 is an example of a "heat-generating component."

3 is a diagram illustrating a state in which the rear cover of the smartphone according to the embodiment is removed. In FIG. 3, the position of the electronic component 151 that cannot be seen from the rear cover 16 side is indicated by a dotted line. In the example of FIG. 3, the vapor chamber 12 is arranged in a rectangular shape so as to reach from near one end of the heat sink 14 to near the other end in the longitudinal direction. Also, in the example of FIG. 3, the vapor chamber 12 is arranged so as to pass through the central portion 1411 of the through hole 141 of the heat sink 14. The electronic component 151 contacts the main body portion 121 of the vapor chamber 12 at one end side of the heat sink 14. Here, by filling the gap between the electronic component 151 and the main body portion 121 with a filler, the gap generated between the electronic component 151 and the main body portion 121 may be reduced, and the efficiency of heat conduction from the electronic component 151 to the main body portion 121 may be increased. The filler is preferably one with high thermal conductivity, and for example, "non-silicone one-component room temperature curing type thermally conductive elastomer" manufactured by Kaneka Corporation may be adopted. Moreover, the heat sink 14 may be in contact with an inner wall surface of a portion that forms a side surface of the front cover 11. By arranging the heat sink 14 on the inner wall surface of the portion that forms the side surface of the front cover 11, the rigidity of the smartphone 1 can be increased.

Figure 4 is an end view of line B-B in Figure 3. As illustrated in Figure 4, the vapor chamber 12 and the heat sink 14 are bonded to each other by thermally conductive double-sided tape 13, with the main body 121 inserted into the through hole 141. Furthermore, a gap 1412 is provided between the main body 121 of the vapor chamber 12 and the heat sink 14, and they do not come into contact with each other. Gap 1412 is an example of a "gap".

Figure 5 is a diagram showing the conduction of heat from the vapor chamber to the heat sink in an embodiment. In Figure 5, the conduction of heat is shown by arrows. The heat conducted from the electronic component 151 to the vapor chamber 12 is conducted to the fluid in the internal region 1213 via the upper plate 1211. The conducted heat is transported to other regions of the vapor chamber 12 by the fluid in the internal region 1213. Furthermore, the heat transported by the fluid in the internal region 1213 is conducted to the heat sink 14 via the bottom plate 1212, the protruding plate 122, and the thermally conductive double-sided tape 13. Here, as described above, the main body 121 of the vapor chamber 12 is not in contact with the heat sink 14, so that direct transport from the main body 121 to the heat sink 14 is suppressed.

6 is a diagram showing the transfer of heat from an electronic component to a heat sink via a vapor chamber in an embodiment. In FIG. 6, the transfer of heat is shown by dotted arrows. FIG. 6 shows the smartphone 1 with the rear cover 16 and the substrate 15 removed. The heat conducted from the electronic component 151 is conducted to the entire main body 121 by the fluid sealed in the main body of the vapor chamber 12. The heat conducted to the main body 121 is conducted to the heat sink 14 through the path described with reference to FIG. 5. Here, as in FIG. 6, if the vapor chamber 12 is arranged to pass through the vicinity of the center of the heat sink 14, the heat can also be conducted to the center of the heat sink 14, which makes it easier to diffuse the heat throughout the entire heat sink 14.

<Effects of the embodiment>
In the embodiment, the vapor chamber 12 is used as a member for transporting heat from the electronic component 151. The vapor chamber 12 has a higher thermal conductivity efficiency than a heat sink, and therefore can diffuse heat from the electronic component 151 more efficiently than when the electronic component 151 and the heat sink 14 are in direct contact with each other.

In the embodiment, the main body 121 of the vapor chamber 12, which becomes thicker as it contains a fluid, is inserted into the through hole 141 of the heat sink 14. Then, the protruding plate 122, which can be easily formed thin, and the heat sink 14 are adhered with thermally conductive double-sided tape 13. By adopting such a configuration, it is easier to make the smartphone 1 thinner than when the main body 121 of the vapor chamber 12 and the heat sink 14 are arranged in an overlapping manner.

In the embodiment, heat from the electronic component 151 is conducted to the heat sink 14 via the main body 121, the protruding plate 122, and the thermally conductive double-sided tape 13. By adopting such a configuration, the conduction of heat from the electronic component 151 to the heat sink 14 can be controlled by the arrangement of the thermally conductive double-sided tape 13. For example, the width of the thermally conductive double-sided tape 13 can be narrowed near other electronic components to reduce the heat conducted to the heat sink 14, or the width of the thermally conductive double-sided tape 13 can be widened to conduct more heat to the heat sink 14 when there is a relatively large space.

7 and 8 are diagrams showing the difference in thermal conduction due to the difference in width of the thermally conductive double-sided tape. FIG. 7 shows an example of the state where the width of the thermally conductive double-sided tape 13 is widened. FIG. 8 shows an example of the state where the width of the thermally conductive double-sided tape 13 is narrowed. In FIG. 7 and FIG. 8, the magnitude of thermal conduction is shown by the number of arrows. As shown in FIG. 7, by widening the width of the thermally conductive double-sided tape 13, the thermal conduction from the vapor chamber 12 to the heat sink 14 can be increased. Also, as shown in FIG. 8, by narrowing the width of the thermally conductive double-sided tape 13, the thermal conduction from the vapor chamber 12 to the heat sink 14 can be suppressed.

In the embodiment, a gap 1412 is provided between the main body 121 and the heat sink 14. Providing such a gap suppresses direct heat conduction from the main body 121 to the heat sink 14. This makes it possible to more suitably control the amount of heat conducted to the heat sink 14 by the arrangement of the thermally conductive double-sided tape 13. The arrangement of the thermally conductive double-sided tape 13 suitable for controlling the amount of heat in the design can be confirmed by appropriate experiments, etc.

In the embodiment, the main body 121 is arranged so as to pass through the vicinity of the center of the heat sink 14. By arranging it in this manner, it becomes easier to conduct heat from the electronic component 151 to the vicinity of the center of the heat sink 14, and as a result, it becomes easier to diffuse the heat throughout the entire heat sink 14.

In the embodiment, the main body 121 is disposed so as to extend from near one end of the rectangular heat sink 14 in the longitudinal direction to near the other end. The electronic component 151 and the main body 121 of the vapor chamber 12 contact each other near one end of the heat sink 14 in the longitudinal direction. By adopting such a configuration, the vapor chamber 12 can easily diffuse the heat of the electronic component 151 to near the other end of the heat sink 14, which is as far away from the electronic component 151 as possible.

The embodiments disclosed above can be modified as appropriate. For example, in the embodiment, the vapor chamber 12 is disposed along the longitudinal direction of the rectangular heat sink 14, but the vapor chamber 12 may be disposed along the lateral direction of the heat sink 14. Also, in the embodiment, the heat sink 14 is formed into a rectangular plate shape, but the heat sink 14 may be formed into other shapes.

1 smartphone 11 front cover 12 vapor chamber 121 main body 1211 upper plate 1212 bottom plate 1213 internal region 122 protruding plate 13 thermally conductive double-sided tape 14 heat sink 141 through hole 1411 central portion 1412 gap 15 substrate 151 electronic component 16 rear cover

Claims (5)

A heat generating component;
a vapor chamber that contains a heat transporting fluid and has a main body that contacts the heat generating component and a protrusion that protrudes from an edge of a bottom of the main body;
a plate-shaped metal structure having a through hole into which the main body is inserted;
a thermally conductive adhesive member that adheres the protrusion and the metal structure to each other so as to overlap the metal structure when viewed in a normal direction of the metal structure,
A gap is formed between the main body and the metal structure,
The thermally conductive adhesive member is disposed between the protrusion and the metal structure with a varying width.
Mobile device. the thermally conductive adhesive member is disposed with a first width in a portion that promotes heat conduction from the heat generating component;
The heat insulating film is disposed at a portion where the heat conduction from the heat generating component is suppressed, with a second width narrower than the first width.
The mobile terminal according to claim 1 . The metal structure is in contact with an inner wall surface of a housing of the mobile terminal.
3. The mobile terminal according to claim 1 or 2. The thermally conductive adhesive member is a double-sided tape.
The mobile terminal according to any one of claims 1 to 3. The vapor chamber is in contact with the heat generating component at a portion of the main body.
A mobile terminal according to any one of claims 1 to 4.

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