JP2016012632A - Housing material, electronic device housing, and electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a housing material which makes possible to ensure a sufficient conductivity and to achieve the reduction in thickness; an electronic device housing arranged by use of such a material; and an electronic device arranged by use of such an electronic device housing.SOLUTION: A housing material 10 comprises a laminate of prepregs 40a and 40b each including carbon fiber 36 consisting of a conductive reinforced fiber and a thermosetting resin 38 impregnated into the carbon fiber, and is used as an electronic device housing 12 of an electronic device 16. The housing material 10 further comprises: a conductive earth member 44 provided on part of its surface and electrically connected to the carbon fiber 36; and a piece of aluminum foil 42 sandwiched between the prepregs 40a and 40b and integrated with them into the laminate.

Description

  The present invention relates to a housing material configured by laminating a plurality of prepregs, which are fiber reinforced plastics, an electronic device housing using the housing material, and an electronic device using the electronic device housing. .

  The casings of various electronic devices such as notebook personal computers (notebook PCs), tablet personal computers (tablet PCs), smartphones, and mobile phones need to be lightweight, thin, and high in strength. Therefore, housing materials made of multiple layers of prepregs (fiber reinforced plastics) in which reinforced fibers such as carbon fibers are impregnated with thermosetting resins such as epoxy resins are widely used for housings of electronic devices. It has been.

  By the way, the electronic device as described above needs to have a predetermined electromagnetic shielding property. For example, Patent Document 1 discloses a configuration that secures a desired electromagnetic wave shielding property by attaching a metal foil to the surface of a housing material formed of a prepreg.

JP 2010-150390 A

  However, in the conventional technology as described above, it is necessary to attach a metal foil by a post-installation operation so as to be placed over a wide area on the surface of the housing material formed by laminating a plurality of layers of the prepreg. Therefore, in consideration of handleability and ease of pasting, the metal foil needs to have a certain thickness, for example, a thickness of about 0.2 mm. For this reason, the thickness of the housing for electronic devices is increased by the thickness of the metal foil, which is a barrier to reducing the thickness of the entire electronic device. In particular, there is a strong demand for thinning portable information devices such as notebook PCs, and it is desirable that even a small thickness can be reduced.

  The present invention has been made in consideration of the above-described problems of the prior art, and a housing material capable of ensuring both sufficient conductivity and thinning, and an electronic apparatus using the housing material. An object of the present invention is to provide a housing for an electronic device and an electronic device using the housing for an electronic device.

  The housing material according to the present invention is a housing material used for electronic equipment, which is formed by laminating a plurality of prepregs obtained by impregnating a conductive reinforcing fiber with a thermosetting resin. A grounding member having conductivity is disposed in part, and the grounding member is electrically connected to the reinforcing fiber.

  According to such a configuration, conduction between the grounding member exposed on a part of the surface and the reinforcing fiber having conductivity extending over the entire area of the housing material is ensured. For this reason, it is possible to achieve both sufficient conductivity and electromagnetic wave shielding properties and reduction in thickness without attaching a metal foil over a wide area of the surface of the housing material.

  When the metal foil is integrated between the prepreg layers and the grounding member and the metal foil are electrically connected via the reinforcing fiber, the conductivity can be more reliably ensured.

  The reinforcing fiber may be carbon fiber.

  When the carbon fibers of adjacent prepreg layers are arranged in contact with each other by being pressed and integrated while heating the grounding member on the surface, the grounding member is reliably integrated with the prepreg. be able to. Moreover, since each layer of the prepreg can be pressed and compressed by the grounding member, the reinforcing fibers between the respective layers can be easily brought into contact with each other.

  When the grounding member has a protrusion that is inserted into the prepreg in the stacking direction and is in contact with the metal foil, the metal foil and the grounding member can be reliably connected.

  When the outer surface of the grounding member is flush with the surface of the portion where the grounding member is not disposed, the grounding member does not protrude on the surface of the housing material.

  An electronic device casing according to the present invention is characterized by using the casing material having the above-described configuration.

  In this case, if the grounding member is disposed on the surface inside the housing, the grounding member is not exposed to the outer surface of the electronic device housing, and electrical conduction within the housing can be easily ensured.

  An electronic device according to the present invention is characterized by using the electronic device casing having the above-described configuration.

  In this case, when the electronic device casing is used as a casing in which the display device is provided, it is possible to ensure the electromagnetic wave shielding property in the display device portion such as a liquid crystal display.

  In the electromagnetic wave shielding structure of the antenna, when the electronic device casing is used as a casing in which an antenna for wireless communication is provided, the electronic device casing has the grounding member at least at a position overlapping the antenna. The grounding member can be easily grounded via carbon fiber or metal foil.

  According to the present invention, electrical conduction between the grounding member and the conductive reinforcing fiber is ensured, and there is no need to attach a metal foil to the surface of the housing material by a retrofitting operation. It is possible to achieve both shielding and thinning.

FIG. 1 is a perspective view of an electronic device including a lid formed of a housing for an electronic device formed of a housing material according to an embodiment of the present invention. FIG. 2 is a plan view schematically showing the configuration of the back cover of the electronic device casing. FIG. 3 is a partially cutaway perspective view schematically showing the configuration of the housing material according to the embodiment of the present invention. 4 is a cross-sectional view schematically showing the configuration of the housing material shown in FIG. FIG. 5 is a cross-sectional view schematically showing a configuration at a portion where the grounding member of the housing material shown in FIG. 3 is disposed. FIG. 6 is a configuration diagram of a grounding member according to a modified example, FIG. 6 (A) is a front view, and FIG. 6 (B) is a bottom view. FIG. 7 is a cross-sectional view schematically showing a configuration of a housing material using the grounding member shown in FIG.

  Hereinafter, the housing material according to the present invention will be described in detail with reference to the accompanying drawings by giving preferred embodiments in relation to an electronic device including an electronic device housing formed of this material. .

  FIG. 1 is a perspective view of an electronic device 16 including a lid body 14 formed of an electronic device casing 12 formed of a casing material 10 according to an embodiment of the present invention. In the present embodiment, a configuration in which an electronic device casing 12 formed of the casing material 10 is used as a lid 14 of an electronic device 16 that is a notebook PC is illustrated. The housing material 10 can be used as a housing material for various electronic devices such as a desktop PC, a tablet PC, a smartphone, or a mobile phone.

  As shown in FIG. 1, the electronic device 16 includes a device main body 20 having a keyboard device 18 and a lid 14 having a display device 22 composed of a liquid crystal display or the like. The lid 14 is connected to the device body 20 by a pair of left and right hinges 24 so as to be openable and closable.

  The device main body 20 includes a main body casing 26 having a top cover 26a and a bottom cover 26b. The upper surface cover 26a is a cover member that covers the upper surface of the device body 20 together with the keyboard device 18 and the like. The bottom cover 26 b is a cover member that covers the side surface and the bottom surface of the device main body 20. Various types of electronic components such as a substrate, a processing unit, a hard disk device, and a memory (not shown) are accommodated in the main body housing 26. A keyboard device 18, a pointing stick 28, and a touch pad 30 are provided as input devices on the upper surface of the device main body 20.

  The lid body 14 includes an electronic device casing 12 having a back cover 12a and a front cover 12b. The back cover 12a is a cover member that covers the side surface and the back surface of the lid body 14, and is formed of the housing material 10 according to the present embodiment. The front cover 12 b is a cover member that covers the front surface of the lid body 14 together with the display device 22. The display device 22 provided on the front surface of the lid body 14 is accommodated between the lid body 14 and the device main body 20 in a state of facing the keyboard device 18 or the like when the lid body 14 is closed with respect to the device main body 20. Is done. A pair of left and right antennas 32 are provided near the upper end portion inside the electronic device casing 12. Each antenna 32 is used for transmission / reception of radio waves used in wireless communication or the like.

  Next, the configuration of the back cover 12a constituting the electronic device casing 12 and the casing material 10 forming the back cover 12a will be specifically described.

  FIG. 2 is a plan view schematically showing the configuration of the back cover 12a of the electronic device casing 12, and shows the inner surface of the back cover 12a in which the display device 22 and the like are accommodated.

  As shown in FIG. 2, the back cover 12 a is a panel-like cover member in which a wall portion serving as a side surface of the electronic device casing 12 is erected on the peripheral portion. In the back cover 12 a, the surface that is the back surface of the lid body 14 is formed of the housing material 10. A pair of recesses 34 and 34 in which the pair of hinges 24 and 24 are disposed are formed in the lower edge portion of the back cover 12a by notches.

  FIG. 3 is a partially cutaway perspective view schematically showing the configuration of the housing material 10 according to an embodiment of the present invention.

  As shown in FIG. 3, the housing material 10 is formed by laminating prepregs 40a and 40b obtained by impregnating a carbon fiber 36, which is a conductive reinforcing fiber, with a thermosetting resin 38 such as an epoxy resin. And an aluminum foil 42 is sandwiched between them.

  The carbon fibers 36 are aligned by drawing, and the arrangement of the carbon fibers 36 is orthogonal to one prepreg 40a and the other prepreg 40b. The laminated structure of the prepregs 40a and 40b is configured symmetrically with respect to the aluminum foil 42, and the prepreg 40a and the prepreg 40b are laminated in this order from the aluminum foil 42 serving as an intermediate layer toward the upper and lower surfaces.

  In the present embodiment, a configuration in which five layers (four layers only for the prepregs 40a and 40b) are stacked in this order from the upper surface to the lower surface is illustrated in this embodiment, although the layers are illustrated in the order of the prepreg 40b, the prepreg 40a, the aluminum foil 42, the prepreg 40a, and the prepreg 40b. The number and order of lamination of the prepregs 40a and 40b can be changed as appropriate, and the number of the aluminum foils 42 can be changed as appropriate. However, in consideration of the warp of the housing material 10, it is preferable that the prepregs 40a and 40b and the aluminum foil 42 have a symmetrical structure from the middle to the upper and lower surfaces in the stacking direction.

  A metal grounding member 44 is disposed on the surface of the housing material 10. The ground member 44 is a metal plate having conductivity such as aluminum or copper. Although details will be described later, the grounding member 44 is integrally disposed when the prepregs 40a and 40b and the aluminum foil 42 are heated and pressed to form the casing material 10 as a laminate. As a result, the outer surface of the ground member 44 is flush with the surface of the housing material 10, and most of it is buried in the housing material 10.

  Each dimension of the housing material 10 can be appropriately changed. For example, the thickness of the housing material 10 in the stacking direction is about 1 mm, and the thickness of the prepregs 40a and 40b is about 0.2 mm. The thickness of 44 is about 0.5 mm. The aluminum foil 42 is obtained by thinly rolling aluminum to a thickness of about 0.2 mm to 0.006 mm. The aluminum foil 42 has an outer shape over the entire area of the housing material 10, and various metal foils such as a copper foil may be used instead of the aluminum foil. The diameter of the carbon fiber 36 is, for example, about 0.007 mm. In the case of this embodiment, about 60 to 70 weight percent of carbon fibers 36 are included in each of the prepregs 40a and 40b.

  FIG. 4 is a cross-sectional view schematically showing the configuration of the housing material 10 shown in FIG. 3, and FIG. 5 is a diagram showing a portion of the housing material 10 shown in FIG. It is sectional drawing which shows a structure typically. 4 and 5, the diameter of the carbon fiber 36 is greatly exaggerated in order to clearly show the state of the carbon fiber 36 included in the prepregs 40a and 40b. However, the actual carbon fiber 36 is as described above. It has a diameter considerably smaller than the thickness of the prepregs 40a and 40b, and FIG.

  The housing material 10 is formed by laminating the carbon fiber 36 and the thermosetting resin 38 and the aluminum foil 42 for forming the prepregs 40a and 40b so as to have the laminated structure described above, and at a desired position on the upper surface thereof. The grounding member 44 is disposed, and the thermosetting resin 38 is cured by pressure molding while heating to about 180 ° C. with a predetermined mold.

  Thereby, in the part where the grounding member 44 is not disposed, the housing material 10 in which the prepregs 40a and 40b and the aluminum foil 42 are laminated is formed as shown in FIG.

  On the other hand, at the portion where the grounding member 44 is disposed, as shown in FIG. 5, the prepregs 40a and 40b and the aluminum foil 42 positioned immediately below the grounding member 44 are pressed and compressed in the stacking direction. In this part, the carbon fibers 36 of the prepregs 40a and 40b receive the pressing force from the ground member 44 and come into contact with each other to push out the thermosetting resin 38 before being cured. As a result, the carbon fibers 36 of adjacent layers are molded into a state in which the surroundings are impregnated with the thermosetting resin 38 while being in contact with each other. Specifically, the carbon fiber 36 of the uppermost prepreg 40b and the carbon fiber 36 of the lowermost prepreg 40a are in contact with each other, and similarly, the carbon fiber 36 of the lowermost prepreg 40b and the carbon fiber of the uppermost prepreg 40a. 36 are in contact with each other. Further, the carbon fibers 36 of the prepregs 40a and 40a sandwiching the aluminum foil 42 and the aluminum foil 42 are in contact with each other.

  Thereby, in the housing material 10, the ground member 44 and the aluminum foil 42 are electrically connected via the carbon fiber 36. That is, most of the surface of the housing material 10 is covered with the thermosetting resin 38 so that it does not have conductivity, but the portion of the ground member 44 has conductivity. The electrically connected carbon fiber 36 and aluminum foil 42 extend over the entire outer shape.

  FIG. 6 is a configuration diagram of a grounding member 46 according to a modification, FIG. 6 (A) is a front view, and FIG. 6 (B) is a bottom view. FIG. 7 is a cross-sectional view schematically showing the configuration of the housing material 10 using the grounding member 46 shown in FIG.

  In the above description, the configuration using the grounding member 44 made of a thin rectangular parallelepiped metal plate is exemplified, but the grounding member 46 has a configuration in which a plurality of needle-like protrusions 46b are provided on the lower surface of the metal plate 46a. As shown in FIG. 6A and FIG. 6B, in this embodiment, the configuration in which six protrusions 46b are arranged on the lower surface of the metal plate 46a is illustrated. The position can be changed as appropriate. The metal plate 46a and the protrusion 46b are made of a conductive metal such as aluminum or copper.

  Also in the case of the housing material 10 using the ground member 46, the carbon fibers 36 and the thermosetting resin 38 and the aluminum foil 42 for forming the prepregs 40a and 40b are laminated so as to have the above-described laminated structure. Then, the grounding member 46 is disposed at a desired position on the upper surface, and is pressure-molded while being heated to, for example, about 180 ° C. with a predetermined mold. In addition, since the protrusion 46b of the grounding member 36 has a sharp tip, it can be molded in a state where it is easily and stably positioned on the upper surface of the laminate.

  Accordingly, as shown in FIG. 7, the prepregs 40 a and 40 b and the aluminum foil 42 positioned immediately below the ground member 46 are pressed and compressed in the stacking direction at the portion where the ground member 46 is disposed. At this time, the protrusions 46b of the ground member 46 enter the stacking direction while pushing the carbon fibers 36 apart, and are put into contact with the aluminum foil 42. Therefore, the metal plate 46a constituting the grounding member 46 and the aluminum foil 42 are electrically connected via the protrusion 46b. Further, in this part, as in the configuration example shown in FIG. 5, the carbon fibers 36 of the prepregs 40a and 40b are in contact with each other while being moved by the pressing force from the grounding member 46, and the carbons of adjacent layers are also in contact with each other. In this state, the thermosetting resin 38 is impregnated around the fibers 36 in contact with each other. For this reason, the metal plate 46 a and the protrusion 46 b and the aluminum foil 42 are also electrically connected by the carbon fiber 36.

  The metal plate 46a constituting the grounding member 46 may have the same thickness as the grounding member 44 described above, and the protrusion 46b can reach the aluminum foil 42 as shown in FIG. It is good to set to the length dimension which does not penetrate 40b.

  In the grounding member 46, the metal plate 46a exposed on the surface and the aluminum foil 42 can be reliably connected by the protrusion 46b. Therefore, when the ground member 46 and the aluminum foil 42 are used, it is not always necessary to compress the carbon fibers 36 and bring the carbon fibers 36 into contact with each other as in the ground member 44 shown in FIG. For this reason, the metal plate 46 a of the grounding member 46 can be much thinner than the grounding member 44.

  The grounding member 44 (46) as described above corresponds to, for example, a position close to the hinge 24 and a position overlapping the antenna 32 on the inner surface of the back cover 12a of the electronic device casing 12 as shown in FIG. To be arranged.

  In the electronic device 16 according to the present embodiment, the wiring from the lid body 14 to the device body 20 is passed through the hinge 24. Therefore, by arranging the grounding member 44 (46) at a position close to the hinge 24, it is possible to easily ground the device body 20 via the hinge 24 in the electromagnetic wave shielding structure on the back cover 12a of the lid body 14. it can. Further, by arranging the grounding member 44 (46) at a position overlapping with the antenna 32, in the electromagnetic wave shielding structure at the antenna 32, the device from the grounding member 44 (46) to the hinge 24 via the aluminum foil 42 and the carbon fiber 36. The main body 20 can be grounded.

  In the housing material 10 according to the present embodiment, the carbon fibers 36 between the respective layers come into contact with each other and are conducted by the pressing by the grounding member 44 (46) as described above. For this reason, the aluminum foil 42 may be omitted, and in that case as well, sufficient electromagnetic shielding properties can be secured over the entire area of the housing material 10. Of course, by providing the aluminum foil 42, even when all the carbon fibers 36 are not sufficiently in contact with each other at the time of molding, the electromagnetic wave shielding property can be surely ensured.

  As described above, the casing material 10 according to the present embodiment has the grounding member 44 (46) having conductivity disposed on a part of the surface, and the grounding member 44 (46) Electrically connected. Thereby, electrical connection between the grounding member 44 (46) exposed on a part of the surface and the carbon fiber 36 extending over the entire region of the housing material 10 is ensured. For this reason, ensuring sufficient electrical conductivity and electromagnetic wave shielding property and thinning of the housing material 10 without attaching a metal foil over a wide area of the surface of the housing material 10 as in the prior art. Both can be achieved.

  In the case material 10, the aluminum foil 42 is sandwiched between the prepregs 40 a and 40 b, and the ground member 44 (46) and the aluminum foil 42 are electrically connected via the carbon fiber 36. The conductivity of the housing material 10 is more reliably ensured. Conventionally, it has been necessary to attach a metal foil to the surface of the housing material by a retrofitting operation. Therefore, it is necessary to use a metal foil having a certain thickness, which is a barrier to reducing the thickness of the housing material. It was. On the other hand, in the case of the housing material 10 according to the present embodiment, the aluminum foil 42 is integrally sandwiched at the time of molding, so that the handleability and arrangement of the aluminum foil 42 are easier than in the case of retrofitting work. In this point, the thinner aluminum foil 42 can be used. The aluminum foil 42 does not increase the thickness of the housing material 10.

  Further, in the housing material 10, the outer surface of the grounding member 44 (46) is integrated with the surface of the housing material 10 by applying pressure while heating with the grounding member 44 (46) disposed on the surface. And become the same. Therefore, the thickness of the housing material 10 is not increased by the grounding member 44 (46).

  It should be noted that the present invention is not limited to the above-described embodiment, and it is needless to say that the present invention can be freely changed without departing from the gist of the present invention.

  For example, in the above-described embodiment, the configuration in which the housing material 10 is used for the electronic device housing 12 of the lid body 14 constituting the electronic device 16 is illustrated, but the housing material 10 forms the device main body 20. It may be used for the bottom cover 26b or the like of the main body casing 26, and may be used for the back cover of a tablet PC or smartphone (not shown).

DESCRIPTION OF SYMBOLS 10 Housing material 12 Electronic device housing 12a Back cover 12b Front cover 14 Lid 16 Electronic device 18 Keyboard device 20 Device body 22 Display device 24 Hinge 26 Body housing 26a Top cover 26b Bottom cover 32 Antenna 36 Carbon fiber 38 Thermosetting resin 40a, 40b Pre-preg 42 Aluminum foil 44, 46 Grounding member 46a Metal plate 46b Projection

Claims (11)

Constructed by laminating a plurality of prepregs impregnated with thermosetting resin into conductive reinforcing fibers, a housing material used in electronic equipment,
A housing material, wherein a grounding member having conductivity is disposed on a part of the surface, and the grounding member is electrically connected to the reinforcing fiber. The housing material according to claim 1,
A housing material, wherein a metal foil is integrated between layers of the prepreg, and the ground member and the metal foil are electrically connected via the reinforcing fiber. The housing material according to claim 2,
The casing material is characterized in that the reinforcing fibers are carbon fibers. The housing material according to claim 3,
A housing material, wherein carbon fibers of adjacent prepreg layers are arranged in contact with each other by being pressed and integrated while being heated in a state where the grounding member is arranged on the surface. In the housing material according to any one of claims 2 to 4,
The casing material, wherein the grounding member has a protrusion that is inserted into the prepreg in the stacking direction and is in contact with the metal foil. The housing material according to claim 4,
The housing material, wherein an outer surface of the grounding member and a surface of a portion where the grounding member is not provided are flush with each other.   A housing for an electronic device, wherein the housing material according to claim 1 is used. The electronic device casing according to claim 7,
A housing for electronic equipment, wherein the grounding member is disposed on a surface on the inside of the housing.   An electronic device using the electronic device casing according to claim 7 or 8. The electronic device according to claim 9, wherein
An electronic apparatus using the electronic apparatus casing as a casing in which a display device is provided. The electronic device according to claim 9 or 10,
An electronic apparatus characterized in that the electronic apparatus casing is used as a casing in which an antenna for wireless communication is provided, and the electronic apparatus casing has the grounding member at a position overlapping at least the antenna.

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