JP2018006449A - Enclosure of electronic apparatus and electronic apparatus - Google Patents

Abstract

[Problem] To provide a housing that minimizes the possibility of failure of electronic components integrated with the housing while maintaining its functionality. [Solution] The housing (1) has a plate-shaped exterior material (4) that forms most of the flat surface, a wiring board (6A) on the surface facing the exterior material (4) with electronic components (5A) mounted, and a wiring board (6B) on the surface opposite the exterior material (4) with electronic components (5B) mounted. A flexible member (9A) is disposed between the wiring board (6A) and the exterior material (4). The flexible member (9A) is formed in a mesh pattern on the surface of the wiring board (6A) facing the exterior material (4) and supports the exterior material (4). A flexible member (9B) similar to the flexible member (9A) is also disposed between the wiring board (6B) and the exterior material (4). [Selected Figure] Figure 2

Description

  The present application relates to a housing of an electronic device and an electronic device.

  In recent years, various electronic devices have been proposed (see, for example, Patent Documents 1-3).

JP-A 64-9695 Japanese Patent Laid-Open No. 11-289168 Japanese Patent No. 2889318

  As one of the measures for downsizing the electronic device, it is conceivable to integrate the electronic component by incorporating it in the housing. However, a housing in which electronic components are integrated is prone to failure when receiving external force. Accordingly, the present application discloses a housing that suppresses as much as possible the possibility of failure of an electronic component integrated with the housing while maintaining the function as the housing.

  The present application discloses the following case. That is, the housing disclosed in the present application includes an exterior material, an electronic component mounted thereon, a substrate integrated with the exterior material, and a mesh-like member provided between the substrate and the exterior material. .

  If it is said housing | casing, possibility of failure of the electronic component integrated with the housing | casing can be suppressed as much as possible, maintaining the function as a housing | casing.

FIG. 1 is a diagram illustrating a housing of the electronic device according to the embodiment. FIG. 2 is a diagram illustrating an example of the internal structure of the housing. FIG. 3 is a perspective view showing an example of the flexible member. FIG. 4 is a diagram illustrating a state of the flexible member when an overall external force is applied to the housing. FIG. 5 is a diagram illustrating a state of the flexible member when a local external force is applied to the housing.

  Hereinafter, embodiments will be described. The embodiment described below is merely an example, and the technical scope of the present disclosure is not limited to the following aspect.

FIG. 1 is a diagram illustrating a housing 1 of an electronic device according to an embodiment. The housing 1 is a component that forms an exterior part of an electronic device, and has a plate-like outer shape as a whole. That is, the housing 1 is a housing having a flat surface 2 that forms a relatively wide main rectangular surface and a side surface 3 that forms an elongated crossing surface along the edge of the flat surface 2. The housing 1 is a housing in which various electronic components are embedded and integrated, and the inside is partitioned into a plurality of blocks according to the function of each electronic component embedded in the housing 1. For example, in the case of an antenna for a wireless LAN (Local Area Network), it is embedded in an elongated block at the end of the plane 2 as indicated by a symbol A in FIG. Further, for example, in the case of an antenna for NFC (Near Field Communication), the central portion of the casing 1 that can easily transmit and receive radio waves to and from a partner machine on which the casing 1 is deceived as indicated by a symbol B in FIG. Embedded in a nearby compartment. Further, in the case of a fingerprint sensor, it is embedded in a section in the vicinity of the corner of the plane 2 where the user holding the casing 1 can easily press the finger, as indicated by reference numeral C in FIG.

  FIG. 2 is a diagram illustrating an example of the internal structure of the housing 1. The housing 1 has, for example, the following internal structure. That is, as shown in FIG. 2, the housing 1 includes a plate-like exterior material 4 that forms most of the plane 2 and a wiring board 6 </ b> A in which an electronic component 5 </ b> A is mounted on the exterior material 4 side surface. And a wiring board 6B on which an electronic component 5B is mounted on the surface opposite to the exterior material 4 side. The wiring board 6A is integrated with the exterior material 4 via a resin frame 7 at the edge of the wiring board 6A. Similarly to the wiring board 6A, the wiring board 6B is integrated with the exterior material 4 via the frame 7 at the edge of the wiring board 6B. A printed wiring 8A that electrically connects the mounted electronic component 5A to other electronic components is formed on the wiring board 6A. A printed wiring 8B similar to the printed wiring 8A is also formed on the wiring board 6B.

  A flexible member 9A is disposed between the wiring board 6A and the exterior material 4. The flexible member 9 </ b> A is formed in a mesh shape on the surface of the wiring board 6 </ b> A on the exterior material 4 side, and supports the exterior material 4. FIG. 3 is a perspective view showing an example of the flexible member 9A. The flexible member 9A has a wall portion 10A formed vertically and horizontally. Since the flexible member 9 has such a wall portion 10A, the flexible member 9 has a mesh-like appearance as a whole. A flexible member 9B similar to the flexible member 9A is also disposed between the wiring board 6B and the exterior material 4.

  Various members are arranged on the mesh of the flexible member 9A and the flexible member 9B. As used herein, “mesh” refers to a portion of a gap between materials forming a flexible member. For example, a fire extinguishing agent 11 that extinguishes the ignited component is provided on a mesh where a component having a high energy density such as a lithium ion battery is mounted. Further, for example, a buffer 12 that relaxes the load transmitted to the component is provided on the mesh where the component that is easily damaged when subjected to a physical load is mounted. In addition, for example, as indicated by a symbol D, a mesh is omitted in a part where no component is mounted in order to increase the strength. For example, when the flexible members 9A and 9B are made of silicone, the portion where the mesh is omitted can be formed in a form like a solid material by filling the portion corresponding to the mesh with silicone of the same material.

  The flexible members 9A and 9B exhibit the following functions.

  FIG. 4 is a diagram illustrating a state of the flexible members 9A and 9B when an overall external force is applied to the housing 1. FIG. The flexible members 9 </ b> A and 9 </ b> B formed in a mesh shape have a form like a structure that supports the exterior material 4 entirely when viewed from the whole. Therefore, for example, when a load is applied to the entire plane 2, the flexible members 9 </ b> A and 9 </ b> B are deformed relative to the exterior material 4, the wiring boards 6 </ b> A and 6 </ b> B, and the frame 7, which are main components of the housing 1. And functions as a member that maintains the structural strength of the entire housing 1.

  FIG. 5 is a diagram illustrating a state of the flexible members 9 </ b> A and 9 </ b> B when a local external force is applied to the housing 1. When viewed locally, the flexible members 9A and 9B having the wall portion 10 have a form in which a plate-like wall standing upright from the wiring boards 6A and 6B partially supports the exterior material 4. Therefore, for example, when a local load is applied to a part of the plane 2, the flexible members 9A and 9B supporting the part are partially deformed. Since the flexible members 9A and 9B are easily deformed with respect to a local load, the load transmitted to the electronic components 5A and 5B is alleviated, so that the possibility of failure of the electronic components 5A and 5B is suppressed. The

  The housing 1 according to the above embodiment is applicable to various electronic devices. Examples of electronic devices suitable for the housing 1 according to the embodiment include various small electronic devices such as a mobile phone, a smartphone, a tablet computer, a PDA (Personal Digital Assistant), a notebook personal computer, and a car navigation device. Can be mentioned.

  In these small electronic devices, there is a tendency to require a casing that is thin and lightweight and has high rigidity. Examples of a material that realizes a thin and lightweight casing having high rigidity include, for example, a resin in which fine glass fibers and carbon fibers are mixed. However, even such a fiber reinforced resin has a flexural modulus of about 15 GPa. The wall thickness is about 0.8 mm at the minimum, and it is actually difficult to further increase the rigidity and thickness.

  In recent years, wearable terminals are becoming widespread. Wearable terminals are used by being worn on the body, and in order to be able to follow the movement of the body, there are also devices in which wiring and parts are mounted on a flexible material such as a thin plastic film, rubber, or elastomer.

  For example, in an electronic device that requires clearance reduction on the order of several tens to several hundreds of micrometers, in order to achieve further thinning and higher functionality, the built-in components are integrated or the volume of the components themselves is reduced. It is effective to do. However, since there is a tradeoff between heat countermeasures and electrical connection with peripheral components, a layout desired by the designer may not always be realized. Therefore, the number of built-in parts can be reduced and an efficient layout can be realized by making the housing parts not only cover parts and appearance parts, but also have electrical functions as in the above embodiment. There is expected.

  As an example of a housing component that also has electrical functions, ribs are provided in the gaps of built-in components that stand perpendicular to the thickness direction of the housing to increase the structural strength, and the strength required for the cover components Can be included. However, since the thickness of the cavity part, which is a part other than the ribs, becomes thin in the case part with such a structure, if a force is applied to the cavity part from the outside of the case, the part is damaged or built directly below. Parts are easily damaged. Further, if there is a gap between the built-in component and the member on the surface of the housing in the cavity portion, the heat dissipation effect is reduced due to heat insulation by the air layer. Therefore, in the case structure in which the built-in component is arranged in the cavity portion formed by the rib, it is difficult to realize a case component that can be practically used with a thickness of about several millimeters.

  In this regard, in the case 1 of the above-described embodiment, the gap between the rigid wiring boards 6A and 6B and the exterior material 4 disposed in each block is filled with the mesh-like flexible members 9A and 9B. The flexible members 9 </ b> A and 9 </ b> B function as a support material for the exterior material 4, and the exterior material 4 is not easily damaged even when a local force is applied to the exterior material 4 from the outside. Further, since the electronic component 5A mounted on the wiring board 6A is formed so as to be in close contact with the flexible member 9A, the flexible member 9A functions as a buffer material, and the force applied to the exterior material 4 is the electronic component. There is no direct transmission to 5A.

  In addition, since the flexible members 9A and 9B have a mesh shape, the force absorption effect is higher than that of a material without a mesh. The effect of absorbing force depends on the size and density of the mesh, and the thickness of the mesh. For example, a structure in which meshes of about 5 mm square are arranged vertically and horizontally may be added in daily use. Both the assumed local force and the overall force can be absorbed in a balanced manner.

Further, the mesh structure of the flexible members 9A and 9B can also serve as a container for selectively placing functional members in the mesh, like the buffer 12 and the fire extinguishing agent 11 described above. Examples of the utilization form of the mesh include filling powder, pouring a resin, and sealing a liquid. That is, buffer materials such as inflatable balloons for the purpose of reducing external forces, ceramic powders and low melting point metals for the purpose of improving thermal conductivity and heat dissipation, and phosphate esters for the purpose of improving flame retardancy and fire extinguishing properties It is conceivable to fill the mesh with the same material as that of the flexible members 9A and 9B for the purpose of adjusting the rigidity or chemicals such as water or the rigidity. Inflated balloons may shrink in volume when used in extremely cold regions, and their functions may deteriorate.For example, if water is placed in the mesh around the inflated balloon, the temperature will fall below freezing. Due to the volume expansion of water when solidified, the mesh of the inflatable balloon portion becomes narrow, and the buffer function of the inflatable balloon is expected to be maintained.

  Moreover, since the housing 1 of the above embodiment has a sandwich structure in which the wiring boards 6A and 6B, the flexible members 9A and 9B, and the exterior material 4 are overlapped, the heat of the electronic components 5A and 5B is flexible. It is easy to be transmitted to the exterior material 4 through the members 9A and 9B. Therefore, for example, the heat radiation effect of the electronic components 5A and 5B is higher than when the flexible members 9A and 9B are omitted and an air layer is provided between the wiring boards 6A and 6B and the exterior material 4.

  Further, in the above embodiment, the shape of each wiring board 6A, 6B was not mentioned. For example, if the shape and size of each block on which each wiring board 6A, 6B is arranged are common, each block It is easy to deal with design changes such as rearrangement of functional parts to be placed on the board and omission of functions.

  By the way, as a raw material of flexible member 9A, 9B, it is possible to use the appropriate | suitable raw material according to the specification of the housing | casing 1 to manufacture other than the above-mentioned silicone excellent in a softness | flexibility and a flame retardance. For example, when it is desired to place more importance on rigidity, a material in which a glass cloth with a coarse mesh is used as a skeleton and a flexible resin is wrapped around a glass fiber can be applied. If the flexible members 9A and 9B are formed so that the end portion of the glass cloth is embedded in the end portion of the housing 1 or the frame 7 that divides each block, the direction in the direction parallel to the plane 2 rather than the direction perpendicular to the plane 2 Since the elasticity is lowered, the force applied to the plane 2 is more effectively dispersed in the lateral direction (direction parallel to the plane), and the force applied to the exterior material 4 and the wiring boards 6A and 6B is alleviated.

  The mesh structure of the flexible members 9A and 9B can be manufactured by various methods. The flexible members 9A and 9B may be, for example, those having an appropriate viscosity selected according to the degree of crosslinking in the case of silicone resin, and having a mesh structure that is moved vertically and horizontally while being discharged from a thin needle such as a dispenser. Good. In addition, the flexible members 9A and 9B may be formed by stacking thin sheets provided with punching holes, for example. In view of forming the flexible members 9A and 9B in a network structure, the flexible members 9A and 9B include, in addition to thermosetting materials, UV curable materials and room temperature curable (moisture curable) materials, It may be selected according to the material of the housing part and the function to be added, thermoplastic elastomer such as polyester or urethane, heat-resistant polyamide, polyphenylene sulfide (PPS), polyetherimide (PEI), etc. The engineering plastics can easily create a network structure by using a simple extruder for hot melt adhesives, a 3D printer, or the like. A non-heated and low-viscosity resin such as an acrylic UV resin is processed by a dispenser or the like, similar to a silicone resin. The ceramic powder or the like of the above functional member can be handled easily by pouring a thermoplastic resin as a binder.

  Hereinafter, an example of the manufacturing method of the housing 1 will be described.

In manufacturing the housing 1, first, the exterior material 4 and other members are prepared. As a material of the exterior material 4 to be prepared, for example, when an antenna is built in the housing 1, glass fiber reinforced plastic (GFRP) is preferably used in consideration of radio wave transmission. Also, carbon fiber reinforced plastic (CFRP) may be used when radio wave transmission is unnecessary, short fiber reinforced plastic is used when the casing 1 is thickened, and a glass substrate is used if there is an appropriate adhesive. If the material is highly rigid such as fiber reinforced plastic, the exterior material 4 can be made as thin as about 0.2 mm, and if it is a normal resin, the exterior material 4 can be made as thin as about 0.6 mm.

  The wiring boards 6A and 6B can be manufactured, for example, by forming printed wiring on a rigid board in advance and mounting appropriate components. The printed wiring can be formed, for example, by printing a conductive paste using silver, copper, or carbon particles that are generally sold on a rigid substrate by various printing methods. As a printing method for the printed wiring, for example, an appropriate printing method according to the dimensional accuracy and film thickness of the printed wiring, such as screen printing, pad printing, dispense printing, and inkjet printing, is selected. When the antenna is formed by wiring printing, the wiring may be raised with an electrically insulating material such as insert molding or a film pasted on a rigid substrate in order to adjust the communication distance.

  After the exterior material 4 and the wiring boards 6A and 6B are prepared, the frame 7 is formed. The frame 7 may be formed by any method, and for example, various methods such as insert molding and additive manufacturing can be applied. When the wiring boards 6 </ b> A and 6 </ b> B are configured to be fitted into the frame 7, it is desirable to form a fitting groove or the like in the frame 7. When bonding or welding the wiring boards 6A and 6B to the frame 7, instead of omitting such a fitting groove, a positioning structure such as a simple step or a positioning pin may be provided. In the case of bonding, in view of repairability, it is preferable to use a hot melt adhesive that can be processed at a temperature at which each member constituting the housing 1 does not melt or break.

  The dimensions of the frame 7 are appropriately determined according to the thickness of the components built in the housing 1. When the thicknesses of the built-in components are different from each other, the size of the gap between the wiring boards 6A and 6B and the exterior material 4 may be changed for each block. Thereby, although locally, the effect of ensuring the volume and clearance inside the product is also expected.

  Subsequently, the flexible members 9A and 9B having a mesh structure are formed in each block. When the flexible members 9A and 9B having a mesh structure are directly formed on the wiring boards 6A and 6B, for example, as described above, silicone resin or thermoplastic resin is discharged into the block by a dispenser or an extruder. At this time, when various functional members such as the buffer 12 are built in the mesh, it is desirable to form the flexible members 9A and 9B while arranging the functional members in the mesh. Usually, the dispenser has a diameter of several tens of μm to several mm even in a general needle discharge type. Therefore, a mesh having a desired pitch can be manufactured by appropriately combining the needles.

  For example, when forming flexible members 9A and 9B by laminating thin sheets, liquid silicone used as a sealant or a gasket can be used as an adhesive between layers. The thin sheet to be laminated as the flexible members 9A and 9B may be a hole processed sheet, or may be hole processed after being laminated. When the material constituting the flexible members 9A and 9B is a material that does not adhere to the wiring board 6 or the frame 7, it is desirable to coat the wiring board 6 with an adhesive in advance. In addition, the flexible members 9A and 9B may be inserted into the block after forming a network structure in a separately prepared mold instead of the above-described method of directly forming on the wiring boards 6A and 6B. Good.

  After the flexible members 9A and 9B are formed, the casing 1 is completed by further combining the exterior material 4.

  A simulation case corresponding to the case 1 of the above embodiment was created and durability was verified. The verification result is shown below.

In this verification, as a simulated case corresponding to an example of the case 1, a simulated case assuming a case of a tablet computer is created, and whether communication is possible when concentrated load or impact load is applied ( The presence or absence of destruction of the antenna element) and the pattern surface temperature in the block when heated from the back to about 70 ° C. with an electric heater were investigated. The simulated housing was manufactured as follows.

That is, in the production of the simulated housing, as a member corresponding to the exterior material 4, glass cloth (trade name: glass cloth manufactured by Unitika Co., Ltd., thickness t = 0.1 mm) is laminated in two layers, and a polycarbonate resin film ( Product name: Mitsubishi Engineering Plastics Co., Ltd. Iupilon (registered trademark) Thickness t = 0.1mm) and heated and pressed in a sandwich at 280 ° C to create a rigid substrate (elastic modulus 10GPa) of about 250x200mm and thickness 0.3mm did. Then, insert molding was further performed, and a portion corresponding to the frame 7 forming a wall having a width of 3 mm and a height of 5 mm was formed with a polycarbonate resin (trade name: Iupilon (registered trademark), Mitsubishi Engineering Plastics Co., Ltd.).

  For the wiring boards 6A and 6B, two types of plates of about 60x70mm and about 60x40mm are prepared, and silver paste (trade name: Harima Kasei Group Co., Ltd. NPS-HB) is screen printed on the surface. On each of the two types of rigid substrates, a first pattern simulating an NFC antenna element (swirl type, outer shape 40 × 50 mm, line width 1 mm, film thickness 15 μm) and a second pattern simulating a wireless LAN element ( A linear type, an outer shape of 2 × 20 mm and a film thickness of 20 μm) was formed. On the first pattern, a frequency adjusting capacitor (1 × 2 mm, thickness 0.1 mm) as an electronic component corresponding to the electronic component 5A is a conductive adhesive (trade name: Fujikura Kasei Co., Ltd. Dotite (registered trademark)). ). Each electrode of the electronic component was formed on the inner surface side of the product with the same silver paste as the main pattern so as to pass through the through hole to the inner surface side of the product, and the rigid substrate on which the antenna was formed was connected to the evaluation substrate. A thermocouple for temperature measurement was installed on the pattern surface.

As equivalent to the flexible members 9A and 9B, a moisture-curing silicone resin (trade name: Cemedine Super X (registered trademark)) is dispensed from a dispenser (trade name: Musashi Engineering Co., Ltd. Needle-type dispenser, needle diameter Φ0.1 mm). A network structure having 100 meshes of about 5 mm square and a depth of 0.5 mm was formed in each block. As shown in Table 1 below, the block in which the mesh structure is formed is a block in which the mesh is empty, a block in which the mesh is filled with an inflation balloon, a block in which the mesh is filled with alumina powder, or a solid having no network structure. Prepared a block.

  The following tests were conducted on the simulated housings created as described above.

<Load heating test>
Attached to the load cell of a tensile / compression tester (trade name: Instron Japan Inc. Instron) from the upper side of the simulated housing placed on a sturdy table, and attached to a round bar-shaped jig (made of SUS) with a Φ15 mm tip. A concentrated load of 15 kgf was applied to each block. After that, each block was connected to an electronic circuit to check whether communication was possible. In addition, an eggplant-type weight having a weight of 100 g was dropped onto the center of each block from 50 cm above the simulated casing, and an impact load was applied. After that, as with the concentrated load, each block was connected to an electronic circuit, and the possibility of communication was examined. The results are shown in Table 2 below.

  As can be seen from Table 2 above, the simulated housing itself and the electrical components did not break if there was a network structure at an appropriate density between the rigid substrates. Further, if the block has a small area, the mesh structure is more effective.

<Heating test>
A simulated housing was placed on an aluminum plate placed on a hot plate with the surface corresponding to the plane 2 facing upward, heated to 70 ° C. for about 10 minutes, and the temperatures in the block were compared. The heating test was performed with three types of blocks A, E, and F. The results are shown in Table 3 below.

  As can be seen from Table 3 above, when the mesh was filled with alumina powder, which is a thermally conductive particle, as a functional member, the temperature rise of the wiring board was suppressed.

  In addition, although the inside of the housing 1 of the above embodiment is partitioned into a plurality of blocks according to the function of each electronic component, it does not have to be partitioned into a plurality of blocks. Moreover, although the housing | casing 1 of the said embodiment was provided with two wiring boards 6A and 6B, it may be provided with one wiring board and may be provided with three or more wiring boards.

  The case 1 according to the above embodiment is confirmed by the above verification even when applied to various electronic devices such as a mobile phone, a smartphone, a tablet computer, a PDA, a notebook personal computer, a car navigation device, and a wearable device. It is thought that the effect which was done is demonstrated.

  1..Case: 2..Plane: 3..Side: 4..Exterior material: 5A, 5B..Electronic parts: 6A, 6B..Wiring board: 7..Frame: 8A, 8B..Printed wiring : 9A, 9B ··· Flexible member: 10A · · Wall: 11 · · Fire extinguisher: 12 · · Buffering agent

Claims (6)

An exterior material,
An electronic component is mounted, and a substrate integrated with the exterior material;
A mesh-like member provided between the substrate and the exterior material,
Electronic equipment housing. The mesh member has wall portions formed vertically and horizontally on the surface of the substrate on the exterior material side.
The housing | casing of the electronic device of Claim 1. A buffer member is provided on at least a part of the mesh of the mesh member.
The housing | casing of the electronic device of Claim 1 or 2. A fire extinguishing agent is provided on at least a part of the mesh of the mesh member.
The housing | casing of the electronic device as described in any one of Claim 1 to 3. The mesh member is formed of a flexible silicone resin.
The housing | casing of the electronic device as described in any one of Claim 1 to 4. An exterior material,
An electronic component is mounted, and a substrate integrated with the exterior material;
A mesh-like member provided between the substrate and the exterior material,
Electronics.

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