Electronic device housing structure

Abstract

This electronic device housing structure is provided with: an electronic circuit component (2) on which a heat-generating component (4a) is mounted; a heat-dissipating component (5) that contacts the heat-generating component (4a) at a contact portion (6a); and a housing (10) that houses the heat-generating component (4a) and the heat-dissipating component (5). The heat-dissipating component (5) has an exposed portion (6b) that is exposed to the outside of the housing (10). The exposed portion (6b) is positioned further to the inside of the housing (10) than the outer surface (11b) of the housing (10).

Description

Electronic device housing structure

[0001] The present invention relates to a housing structure for an electronic device. This application claims priority to Japanese Patent Application No. 2023-215681, filed on December 21, 2023, the contents of which are incorporated herein by reference.

[0002] For example, Patent Document 1 discloses a housing structure for an electronic device in which electronic components (heat-generating components) inside the housing are thermally connected to heat-dissipating components exposed to the outside of the housing, and heat generated from the heat-generating components is dissipated from the heat-dissipating components to the outside of the housing.

[0003] Japanese Patent Application Publication No. 2006-245025

[0004] However, in the above-mentioned conventional configuration, while the heat dissipation component is exposed to the outside of the housing, the outer surface of the housing and the outer surface of the heat dissipation component are flush with each other. Therefore, for example, if another component is placed in contact with the outer surface of the heat dissipation component, the heat dissipation component is less likely to come into contact with the outside air, which reduces the heat dissipation effect of the heat dissipation component.

[0005] The present invention aims to enhance the heat dissipation effect by exposing heat dissipation components in a housing structure for an electronic device in which heat-generating electronic components and heat dissipation components are housed within the housing.

[0006] As a means for solving the above problems, an embodiment of the present invention has the following configuration: (1) A housing structure for an electronic device according to an embodiment of the present invention is a housing structure for an electronic device (1) including an electronic circuit component (2) having a heat-generating component (4a) mounted thereon, a heat-dissipating component (5) contacting the heat-generating component (4a) at a contact portion (6a), and a housing (10) accommodating the heat-generating component (4a) and the heat-dissipating component (5), wherein the heat-dissipating component (5) has an exposed portion (6b) exposed to the outside of the housing (10), and the exposed portion (6b) is located inside the housing (10) relative to an outer surface (11b) of the housing (10). According to the housing structure of the electronic device described in (1) above of the present invention, the heat dissipation component that dissipates heat from the heat-generating component has an exposed portion that is exposed to the outside of the housing, and the exposed portion of the heat dissipation component is located inside the housing rather than the outer surface of the housing. Therefore, even if other components are placed in contact with the outer surface of the housing, an air layer is secured between the other components and the exposed portion, and the heat from the heat-generating component can be dissipated efficiently.

[0007] (2) In the housing structure for an electronic device described in (1) above, the heat dissipation component (5) may have a non-exposed portion (6c) that is not exposed to the outside of the housing (10), and the exposed portion (6b) may be located closer to the heat-generating component (4a) than the non-exposed portion (6c). According to the housing structure for an electronic device described in (2) above of the present invention, by locating the exposed portion of the heat dissipation component closer to the heat-generating component than the non-exposed portion, the heat conduction path from the heat-generating component to the exposed portion can be shortened, and heat from the heat-generating component can be prevented from being conducted to the non-exposed portion.

[0008] (3) In the housing structure for an electronic device described in (2) above, the heat dissipation component (5) may have a step (6d) between the exposed portion (6b) and the non-exposed portion (6c) or on at least one of them, and the step (6d) may displace the non-exposed portion (6c) to a position closer to the outer surface (11b) of the housing (10) than the exposed portion (6b). According to the housing structure for an electronic device described in (3) above, the non-exposed portion of the heat dissipation component is positioned closer to the outer surface of the housing than the exposed portion, so that the exposed portion is positioned relatively closer to the heat-generating component inside the housing. This shortens the heat conduction path from the heat-generating component to the exposed portion, and suppresses heat conduction from the heat-generating component to the non-exposed portion.

[0009] (4) In the housing structure for an electronic device described in (2) or (3) above, a space (K2) may be provided between the non-exposed portion (6 c) and the inner surface (11 c) of the housing (10). According to the housing structure for an electronic device described in (4) above of the present invention, by providing a space between the non-exposed portion of the heat dissipation component and the inner surface of the housing, the spatial capacity inside the housing can be increased and the housing can be prevented from becoming too hot.

[0010] (5) The housing structure for an electronic device described in (3) above may include a sealing member (11a2) that tightly contacts the heat dissipation component (5) and the housing (10), and the sealing member (11a2) may be positioned close to the outer surface (11b) of the housing (10) by the step portion (6d). According to the housing structure for an electronic device described in (5) above, by including a sealing member that tightly contacts the heat dissipation component and the housing, the elasticity of the sealing member allows thermal deformation of the heat dissipation component, and the sealing effect, such as waterproofing, between the heat dissipation component and the housing can be maintained even when the heat dissipation component is heated. Furthermore, by varying the height of the sealing member and the exposed portion (providing a step portion), the shape of the sealing member is stabilized even when the exposed portion is heated, and a decrease in waterproofing effect can be suppressed.

[0011] (6) In the housing structure for an electronic device described in any one of (1) to (3) above, the exposed portion (6b) may have a flat exposed outer surface (6e1), and the contact portion (6a) and the exposed portion (6b) may be arranged so that at least a portion of them overlap each other when viewed from the normal direction (Z) of the exposed outer surface (6e1). According to the housing structure for an electronic device described in (6) above of the present invention, the contact portion, and therefore the heat-generating component and the exposed portion are arranged so that they overlap each other when viewed from the normal direction of the exposed outer surface, so that the heat-generating component is located on the back side of the exposed portion, thereby improving the heat dissipation effect of the heat-generating component.

[0012] (7) In the housing structure for an electronic device described in any one of (1) to (3) above, the heat dissipation component (5) may have a plurality of the exposed portions (6 b). According to the housing structure for an electronic device described in (7) above of the present invention, the heat dissipation component has a plurality of exposed portions that are exposed to the outside of the housing, thereby improving the heat dissipation effect of the electronic device.

[0013] According to an aspect of the present invention, in a housing structure for an electronic device in which heat-generating electronic components and heat-dissipating components are housed within a housing, the heat-dissipating effect can be improved by exposing the heat-dissipating components.

[0014] 1 is a perspective view of an electronic device according to an embodiment of the present invention, seen from one side in a thickness direction; FIG. 2 is a perspective view of the electronic device, seen from the other side in a thickness direction; FIG. 3 is an exploded perspective view of the electronic device; and FIG. 4 is a cross-sectional view taken along the line IV-IV of FIG.

[0015] An embodiment of the present invention will now be described with reference to the drawings. Fig. 1 is a perspective view of an electronic device 1 according to the embodiment, as seen from one side (top) in the thickness direction Z, and Fig. 2 is a perspective view of the electronic device 1 as seen from the other side (bottom) in the thickness direction Z.

[0016] As shown in Figures 1 and 2, the electronic device 1 of this embodiment has a generally rectangular parallelepiped outer shape. The electronic device 1 has a flat shape with a reduced thickness dimension. The thickness direction is one of three mutually orthogonal directions, and the thickness dimension is smaller than the other two dimensions. For convenience of explanation, the thickness direction will be described as the up-down direction (indicated by arrow Z in the figures), but this does not limit the arrangement of the electronic device 1. In the figures, arrow Z1 indicates upward, and arrow Z2 indicates downward. In the figures, arrows X and Y indicate the left-right direction X and the front-back direction Y, respectively, which are parallel to the front and back surfaces of the substrate 3.

[0017] The electronic device 1 is used, for example, in a vehicle control device, a communication device, etc. The electronic device 1 is fixed in a positioned state to a vehicle body frame or a component fixed to the vehicle body frame at an arbitrary location on the vehicle body, for example.

[0018] Fig. 3 is an exploded perspective view of electronic device 1, and Fig. 4 is a cross-sectional view taken along line IV-IV in Fig. 1. Referring to Figs. 3 and 4, electronic device 1 includes electronic circuit component 2 having a plurality of electronic components 4 including heat-generating component 4a mounted thereon, heat-dissipating component 5 that contacts heat-generating component 4a at contact portion 6a, and housing 10 that houses heat-generating component 4a and heat-dissipating component 5.

[0019] The electronic circuit component 2 has electronic components 4 mounted on the front and back surfaces of a flat printed wiring board 3. The thickness direction of the electronic device 1 (thickness direction of the board 3) is the same as the thickness direction of the housing 10. In the electronic device 1, the electronic circuit component 2, the upper plate 11 and bottom plate 12 constituting the housing 10, and the upper shield plate 6 and lower shield plate 7 constituting the shield component (heat dissipation component) 5 are arranged so as to overlap in the thickness direction.

[0020] Each of the electronic components 4 is, for example, an integrated circuit package. At least one of the electronic components 4 is a heat-generating component 4a that incorporates a circuit that generates a large amount of heat, such as a power amplifier or a power supply circuit.

[0021] The heat dissipation component 5 is made of an aluminum alloy or the like, and functions as a shielding case that surrounds the electronic circuit component 2. The heat dissipation component 5 includes an upper shield plate 6 that forms the upper side in the vertical direction Z, and a lower shield plate 7 that forms the lower side in the vertical direction Z. The upper shield plate 6 and the lower shield plate 7 have small irregularities and steps, but are generally flat plates that are perpendicular to the vertical direction Z.

[0022] The heat dissipation component 5 is made of a metal material with a higher thermal conductivity than the housing 10. The heat dissipation component 5 has an exposed portion 6b that is exposed to the outside of the housing 10 through an opening 11a formed in the top plate portion 11 of the housing 10. The electronic device 1 can dissipate heat generated by the heat-generating component 4a of the electronic component 4 through the opening 11a of the housing 10 to the space outside the housing 10. In other words, the shielding component 5 also serves as the heat dissipation component 5.

[0023] The housing 10 is formed, for example, from a heat-resistant synthetic resin material. The housing 10 includes a top plate 11 that forms the upper side in the vertical direction Z and a bottom plate 12 that forms the lower side in the vertical direction Z. The top plate 11 and the bottom plate 12 have small irregularities, steps, and an opening 11a (described later), but are generally flat and perpendicular to the vertical direction Z. Left and right side plate portions 13 and front and rear side plate portions 14 are integrally formed on the four sides of the top plate 11 in a plan view, extending toward the bottom plate 12. The top plate 11, the left and right side plate portions 13, and the front and rear side plate portions 14 form a container shape that opens downward, and the bottom opening of this container shape is closed by the bottom plate portion 12. Connectors 4c, 4d that enable external wiring to be connected to the electronic circuit component 2 are arranged on either the left and right side plate portions 13 or the front and rear side plate portions 14.

[0024] Fixing flanges 15 are formed along the underside of the housing 10 and protrude from both the left and right sides. For example, a pair of fixing flanges 15 is provided on each of the left and right sides of the electronic device 1, one at the front and one at the rear. The electronic device 1 is attached and fixed to any location on the vehicle body by these multiple fixing flanges 15. Each fixing flange 15 may be fixed to the vehicle body via a vibration-isolating member such as vibration-isolating rubber.

[0025] The upper shield plate 6 of the heat dissipation component 5 has a contact portion 6a that is thermally connected to the heat-generating component 4a via a thermally conductive sheet 4b or the like. When viewed from the vertical direction Z, the contact portion 6a is formed, for example, to have a similar shape but slightly larger than the heat-generating component 4a, or is formed in an area large enough to accommodate multiple heat-generating components 4a. When viewed from the vertical direction Z, the contact portion 6a is, for example, rectangular, with its front, rear, left, and right sides parallel to the front, rear, left, and right sides of the substrate 3.

[0026] In this embodiment, each electronic component 4 is also rectangular when viewed in the vertical direction Z, with its front, rear, left, and right sides parallel to the front, rear, left, and right sides of the substrate 3. The contact portions 6a are joined to the corresponding heat-generating components 4a via a heat-conducting sheet 4b or the like having high thermal conductivity. The heat-conducting sheet 4b may be made of other heat-dissipating materials, such as thermally conductive grease or gel.

[0027] The housing 10 has an opening 11a in at least the upper plate 11 that partially exposes the heat dissipation component 5 to the outside of the housing 10. The opening 11a is formed in a similar rectangular shape that is slightly larger than the contact portion 6a when viewed from the vertical direction Z. A peripheral rib 11a1 is formed on the periphery of the opening 11a, standing toward the heat dissipation component 5. The tip of the peripheral rib 11a1 is spaced from the surface of the heat dissipation component 5, and a seal member 11a2 provided at this tip contacts the heat dissipation component 5.

[0028] The sealing member 11a2 is an elastic member such as rubber, and adheres tightly to the surface of the heat dissipation component 5 in a deflected state. This prevents foreign matter such as water or sand from entering the housing 10 through the opening 11a, and maintains sealing performance even when the electronic device 1 is subjected to vibrations or when the heat dissipation component 5 or other components are thermally deformed. The sealing member 11a2 may be, for example, an adhesive that remains elastic even after hardening. The sealing member 11a2 may also be made of a material with high thermal conductivity, similar to the heat dissipation component 5.

[0029] The heat dissipation component 5 has an exposed portion 6b that exposes the area overlapping with the contact portion 6a to the outside of the housing 10 when viewed from the vertical direction Z. The exposed portion 6b is located inside (below) the housing 10 relative to the outer surface (top surface) 11b of the housing 10 in the vertical direction Z. This ensures an air layer K1 between the exposed portion 6b and another component, ensuring heat dissipation from the exposed portion 6b, even when another component is placed in contact with one side surface (top surface 11b) of the housing 10 in the thickness direction Z. The electronic device 1 has multiple exposed portions 6b. That is, multiple exposed portions 6b are provided corresponding to the multiple heat-generating components 4a of the electronic circuit component 2. This improves the heat dissipation of the entire electronic device 1.

[0030] In the electronic device 1, the shielding metal plate (heat dissipation component 5) is exposed to the outside air (external space) at each location of the heat-generating component 4a. As a result, the heat dissipation path for the heat generated by the heat-generating component 4a is shortest, with paths A and B, which run from the electronic component 4 through the heat dissipation sheet 4b to the shielding metal plate and then radiated into the outside air, improving heat dissipation from the exposed portion 6b. In other words, by setting the heat transfer paths A and B, which have low thermal resistance, in the exposed portion 6b, the radiation efficiency (ratio) from the exposed portion 6b increases, reducing convection C outside the exposed portion 6b (inside the housing 10), and lowering the temperature inside the housing 10.

[0031] The portion of the heat dissipation component 5 excluding the exposed portion 6b, which is located outside the opening 11a (outside the sealing member 11a2) when viewed in the vertical direction Z, is a non-exposed portion 6c that is not exposed to the outside of the housing 10. The non-exposed portion 6c is located closer to the outer surface of the housing 10 in the vertical direction Z than the flat portion 6e of the exposed portion 6b.

[0032] In the embodiment, a step portion 6d including a slope rising in the vertical direction Z is formed on the outer peripheral edge of the exposed portion 6b. The area of ​​the exposed portion 6b that is inside the step portion 6d is a flat portion 6e that is planar and parallel to the top surface 11b of the housing 10, and the area that is outside the step portion 6d is a frame portion 6f that is displaced upward (toward the top surface 11b) relative to the flat portion 6e. The frame portion 6f is formed flush with the non-exposed portion 6c.

[0033] The step portion 6d is located inside the opening 11a when viewed from the vertical direction Z. The non-exposed portion 6c is located outside the opening 11a when viewed from the vertical direction Z. The step portion 6d displaces the sealing member 11a2 toward the top surface 11b of the housing 10. The step portion 6d also functions to reinforce the portion (frame portion 6f) with which the sealing member 11a2 is in close contact. The step portion 6d is not limited to being formed in the exposed portion 6b, and may be formed in the non-exposed portion 6c or in both the exposed portion 6b and the non-exposed portion 6c. The step portion 6d may be formed between the exposed portion 6b and the non-exposed portion 6c (in the area overlapping with the sealing member 11a2 in a plan view).

[0034] The flat portion 6e of the exposed portion 6b is closer to the heat dissipation component 5 than the non-exposed portion 6c, thereby contributing to shortening the heat dissipation path from the heat dissipation component 5 to above the exposed portion 6b. Furthermore, the depth from the outer surface (top surface 11b) of the housing 10 to the outer surface (exposed outer surface 6e1) of the flat portion 6e of the exposed portion 6b is increased, thereby increasing the thickness of the air layer K1 between the outer surface of the housing 10 and the exposed outer surface 6e1. The stepped portion 6d also improves the rigidity of the shielding sheet metal. An internal housing space K2 is formed between the non-exposed portion 6c and the inner surface (bottom surface 11c) of the upper wall (upper plate portion 11) of the housing 10. This prevents temperature propagation from the non-exposed portion 6c to the housing 10, even if the non-exposed portion 6c becomes hot due to convection between the exposed portion 6b and the non-exposed portion 6c.

[0035] The contact portion 6a and the exposed portion 6b are arranged so that they at least partially overlap each other when viewed from the normal direction (vertical direction Z) of the exposed outer surface 6e1. In this embodiment, the exposed portion 6b is slightly larger than the contact portion 6a, and the entire contact portion 6a overlaps with the exposed portion 6b. Furthermore, the entire exposed portion 6b overlaps with the opening 11a. This ensures that heat from the contact portion 6a is dissipated to the outside of the housing 10 through the opening 11a.

[0036] As described above, the housing structure of the electronic device 1 in the above embodiment includes an electronic circuit component 2 on which a heat-generating electronic component 4 (heat-generating component 4a) is mounted, a heat-dissipating component 5 that contacts the heat-generating component 4a at the contact portion 6a, and a housing 10 that houses the heat-generating component 4a and the heat-dissipating component 5, wherein the heat-dissipating component 5 has an exposed portion 6b that is exposed to the outside of the housing 10, and the exposed portion 6b is located inside (below) the housing 10 relative to the outer surface (top surface 11b) of the housing 10. With this configuration, the heat-dissipating component 5 that dissipates heat from the heat-generating component 4a has the exposed portion 6b that is exposed to the outside of the housing 10, and the exposed portion 6b of the heat-dissipating component 5 is located inside the housing 10 relative to the outer surface 11b of the housing 10. Therefore, even if another component is placed in contact with the outer surface 11b of the housing 10, an air layer K1 is secured between the other component and the exposed portion 6b, and heat from the heat-generating component 4a can be efficiently dissipated.

[0037] In the housing structure of the electronic device 1, the heat dissipation component 5 has a non-exposed portion 6c that is not exposed to the outside of the housing 10, and the exposed portion 6b is located closer to the heat-generating component 4a than the non-exposed portion 6c in the normal direction Z of the outer surface 11b. With this configuration, the exposed portion 6b of the heat dissipation component 5 is located closer to the heat-generating component 4a than the non-exposed portion 6c, thereby shortening the heat conduction path from the heat-generating component 4a to the exposed portion 6b and preventing heat from being conducted from the heat-generating component 4a to the non-exposed portion 6c.

[0038] In the housing structure of the electronic device 1, the heat dissipation component 5 has a step 6d between the exposed portion 6b and the non-exposed portion 6c or on at least one of them, and the step 6d displaces the non-exposed portion 6c to a position closer to the outer surface 11b of the housing 10 than the exposed portion 6b in the normal direction Z of the outer surface 11b. With this configuration, the non-exposed portion 6c of the heat dissipation component 5 is positioned closer to the outer surface of the housing 10 than the exposed portion 6b, so that the exposed portion 6b is positioned relatively closer to the heat-generating component 4a inside the housing 10. This shortens the heat conduction path from the heat-generating component 4a to the exposed portion 6b, and suppresses heat conduction from the heat-generating component 4a to the non-exposed portion 6c.

[0039] The housing structure of the electronic device 1 has a space K2 between the non-exposed portion 6c and the inner surface 11c of the housing 10, and the sealing member 11a2 is positioned close to the outer surface (top surface 11b) of the housing 10 by the step portion 6d. With this configuration, by providing the space K2 between the non-exposed portion 6c of the heat dissipation component 5 and the inner surface 11c of the housing 10, the spatial capacity inside the housing 10 is increased and it is possible to prevent the housing 10 from becoming too hot. Furthermore, by changing the height of the sealing member 11a2 and the exposed portion 6b (by providing the step portion 6d), the shape of the sealing member 11a2 is stable even when the exposed portion 6b is heated, and it is possible to prevent a decrease in the waterproof effect.

[0040] The housing structure of the electronic device 1 has a sealing member 11a2 that tightly contacts the heat dissipation component 5 and the housing 10. With this configuration, by having the sealing member 11a2 that tightly contacts the heat dissipation component 5 and the housing 10, the elasticity of the sealing member 11a2 allows thermal deformation of the heat dissipation component 5, and the sealing effect, such as waterproofing, between the heat dissipation component 5 and the housing 10 can be maintained even when the heat dissipation component 5 is heated.

[0041] In the housing structure of the electronic device 1, the exposed portion 6b has a flat exposed outer surface 6e1, and the contact portion 6a and the exposed portion 6b are arranged to at least partially overlap each other when viewed from the normal direction Z of the exposed outer surface 6e1. According to this configuration, the contact portion 6a, and therefore the heat-generating component 4a and the exposed portion 6b are arranged to overlap each other when viewed from the normal direction Z of the exposed outer surface 6e1, so that the heat-generating component 4a is located on the back side of the exposed portion 6b, thereby improving the heat dissipation effect of the heat-generating component 4a.

[0042] In the housing structure of the electronic device 1, the heat dissipation component 5 has a plurality of exposed portions 6b. According to this configuration, the heat dissipation component 5 has a plurality of exposed portions 6b exposed to the outside of the housing 10, thereby improving the heat dissipation effect of the electronic device 1.

[0043] The present invention is not limited to the above-described embodiment, and for example, although the housing structure of the electronic device 1 of the present embodiment is applied to a vehicle, the present invention is not limited to application to vehicles and may be applied to various vehicles and moving bodies such as various transportation equipment such as aircraft and ships, as well as construction machinery and industrial machinery. The configuration in the above-described embodiment is an example of the present invention, and various modifications are possible within the scope of the gist of the present invention, such as replacing the components of the embodiment with well-known components.

[0044] REFERENCE SIGNS LIST 1 Electronic device 2 Electronic circuit component 4 Electronic component 4a Heat-generating component 5 Heat-dissipating component 6a Contact portion 6b Exposed portion 6c Non-exposed portion 6d Step portion 10 Housing 11b Upper surface (outer surface) 11c Lower surface (inner surface) 11a2 Sealing member K1 Air layer K2 Space Z Normal direction

Claims

1. A housing structure for an electronic device comprising: an electronic circuit component (2) having a heat-generating component (4a); a heat-dissipating component (5) that contacts the heat-generating component (4a) at a contact portion (6a); and a housing (10) that houses the heat-generating component (4a) and the heat-dissipating component (5), wherein the heat-dissipating component (5) has an exposed portion (6b) that is exposed to the outside of the housing (10), and the exposed portion (6b) is located inside the housing (10) relative to an outer surface (11b) of the housing (10).

2. The housing structure of an electronic device as described in claim 1, characterized in that the heat dissipation component (5) has a non-exposed portion (6c) that is not exposed to the outside of the housing (10), and the exposed portion (6b) is positioned closer to the heat-generating component (4a) than the non-exposed portion (6c).

3. The housing structure for an electronic device described in claim 2, characterized in that the heat dissipation component (5) has a step portion (6d) between the exposed portion (6b) and the non-exposed portion (6c) or on at least one of them, and the step portion (6d) displaces the non-exposed portion (6c) to a position closer to the outer surface (11b) of the housing (10) than the exposed portion (6b).

4. The electronic device housing structure according to claim 2 or 3, characterized in that a space (K2) is provided between the non-exposed portion (6c) and the inner surface (11c) of the housing (10).

5. The housing structure for an electronic device as described in claim 3, further comprising a sealing member (11a2) that seals the heat dissipation component (5) and the housing (10), the sealing member (11a2) being positioned close to the outer surface (11b) of the housing (10) by the step portion (6d).

6. A housing structure for an electronic device described in any one of claims 1 to 3, characterized in that the exposed portion (6b) has a flat exposed outer surface (6e1), and the contact portion (6a) and the exposed portion (6b) are arranged so that at least a portion of them overlap each other when viewed from the normal direction (Z) of the exposed outer surface (6e1).

7. The electronic device housing structure according to any one of claims 1 to 3, characterized in that the heat dissipation component (5) has a plurality of the exposed portions (6b).

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