JP6272022B2 - Electronics - Google Patents

Description

  The present invention relates to an electronic device that transmits a sound to a user by vibrating a panel by applying a predetermined electrical signal to a piezoelectric element and transmitting the vibration of the panel to a human body.

  Patent Document 1 discloses an electronic device such as a mobile phone terminal that transmits a human body vibration sound to an object in contact with a panel by vibrating the panel due to deformation of a piezoelectric element attached to the panel. Have been described. Patent Document 1 describes that human body vibration sound is sound transmitted to the user's auditory nerve through a part of the user's body (for example, cartilage of the outer ear) that comes into contact with the vibrating object. ing.

Patent No. 5255142

  In the electronic device described in Patent Document 1, further improvement in sound pressure characteristics is desired for various applications.

  An object of the present invention is to provide an electronic device in which a sound pressure characteristic can be further improved in an electronic device in which a piezoelectric element is attached to a panel.

  An electronic apparatus according to the present invention includes a housing, a panel held by the housing, and a piezoelectric element attached to the panel, and the panel is deformed due to deformation of the piezoelectric element. The electronic device transmits a human body vibration sound to an object in contact with the panel, and includes a sheet member between the casing and the panel, and the sheet member includes a part of the sheet member on the panel. The other part different from the part is joined to the casing, and the panel and the casing are both attached between the part and the other part of the sheet member. There are no areas.

  Further, the region of the sheet member may be deformed following the deformation of the panel.

  Further, the region of the sheet member may be deformed in a direction parallel to the vibration direction of the panel.

  Further, the region of the sheet member may be deformed in a direction perpendicular to the vibration direction of the panel.

  Further, the piezoelectric element is attached to the surface of the sheet member opposite to the surface attached to the panel, and when the panel is viewed in plan, the region of the sheet member to which the panel is attached; The sheet member may have a region at least overlapping with a region where the piezoelectric element is attached.

  Further, adjacent to the region of the sheet member to which the panel is attached or the region of the sheet member to which the piezoelectric element is attached, the region of the sheet member to which neither the casing nor the panel is attached. May be formed.

  Moreover, the width | variety of the said area | region in the said sheet | seat member may be changeable in the short side direction of the said panel.

  The sheet member may be made of a PET film, an acrylic film, or a polyamide resin film.

  The sheet member may be a touch panel.

  Further, the sheet member may be a scattering prevention sheet that prevents the glass constituting the panel from scattering.

  The sheet member may be a double-sided tape.

In the double-sided tape, an adhesive layer may not be disposed in an area where the panel and the casing are not attached. The electronic device according to the present invention is held by the casing and the casing. An electronic device that transmits a human body vibration sound to an object that contacts the panel due to deformation of the piezoelectric element due to deformation of the piezoelectric element, and a piezoelectric element attached to the panel. And a sheet member is provided between the casing and the panel, wherein the sheet member has a part of the sheet member joined to the panel and another part different from the part joined to the casing. The sheet member has a deformation region between the part and the other part.

  An electronic apparatus according to the present invention includes a housing, a panel held by the housing, and a piezoelectric element attached to the panel, and the panel is caused by deformation of the piezoelectric element. An electronic device that vibrates and transmits a human body vibration sound to an object that contacts the panel, wherein the panel has one end of the panel attached to the housing by a joining member, and is opposite to the one end of the panel. The other end is attached to the housing via a sheet member, and the sheet member has a part of the sheet member joined to the panel and another part different from the part joined to the housing. The fixing strength between the other end of the panel and the casing is lower than the fixing strength between the one end of the panel and the casing.

  According to the electronic device according to the present invention, it is possible to provide the electronic device in which the sound pressure characteristics can be further improved in the electronic device in which the piezoelectric element is attached to the panel.

It is a figure which shows the functional block of the electronic device which concerns on one Embodiment of this invention. It is a figure which shows the suitable shape of a panel. It is a figure which shows the basic structure of the electronic device which concerns on embodiment of this invention. It is a figure which shows an example of the vibration of the panel of the electronic device which concerns on embodiment of this invention. It is sectional drawing which shows the detailed structure of the electronic device which concerns on embodiment of this invention. It is a figure which shows the conventional structure in the electronic device with which the piezoelectric element was attached to the panel. It is sectional drawing which shows the structure of this invention at the time of using a double-sided tape as a sheet | seat member. It is a figure which shows the frequency characteristic of the electronic device in embodiment of this invention. (A), (b), (c) is sectional drawing which showed multiple modifications of the structure of this invention, respectively. (A), (b) is sectional drawing which showed several further modifications of the structure of this invention, respectively. It is a figure for demonstrating the cross-sectional structure in a different position in the short side direction of the main surface of an electronic device. It is sectional drawing which shows the structure of this invention at the time of using a scattering prevention sheet | seat as a sheet | seat member. In an embodiment in the present invention, it is a sectional view showing the composition by which the piezoelectric element was attached to the case.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram showing functional blocks of an electronic device 1 according to an embodiment of the present invention. The electronic device 1 is, for example, a mobile phone (smart phone), and includes a panel 10, a display unit 20, a piezoelectric element 30, an input unit 40, and a control unit 50.

  The panel 10 is a touch panel that detects contact or a cover panel that protects the display unit 20. For example, it is formed of a synthetic resin such as glass or acrylic, sapphire, or the like. Here, sapphire is made of aluminum oxide (AlO 3) crystals and is industrially manufactured. The shape of the panel 10 may be a plate shape. The panel 10 may be a flat plate or a curved panel having a curved surface in part. When the panel 10 is a touch panel, the touch of a user's finger, pen, stylus pen, or the like is detected. As a detection method of the touch panel, an arbitrary method such as a capacitance method, a resistance film method, a surface acoustic wave method (or an ultrasonic method), an infrared method, an electromagnetic induction method, a load detection method, or the like can be used.

  The display unit 20 is a display device such as a liquid crystal display, an organic EL display, or an inorganic EL display. Furthermore, a flexible display having flexibility may be used. Suitable characteristics of the flexible display include, for example, a thickness of about 0.1 mm and a curvature radius of about 4 mm, and an organic EL display is most suitable for this. The display unit 20 is provided on the back surface of the panel 10. The display unit 20 is disposed on the back surface of the panel 10 by a bonding member (for example, an adhesive). The display unit 20 may be disposed apart from the panel 10 and supported by the housing of the electronic device 1. Or in a suitable mode, display part 20 may be joined to the back of panel 10 with a joining member (for example, adhesives). The joining member is, for example, an elastic resin such as an optical elastic resin in which the refractive index of light to be transmitted is controlled. The display unit 20 displays various information through the bonding member and the panel 10.

  The piezoelectric element 30 is an element that expands or contracts or bends according to an electromechanical coupling coefficient of a constituent material by applying an electric signal (voltage). For these elements, for example, those made of ceramic or quartz are used. The piezoelectric element 30 may be a unimorph, bimorph, or multilayer piezoelectric element. The stacked piezoelectric element includes a stacked bimorph element in which bimorphs are stacked (for example, 16 layers or 24 layers are stacked). The laminated piezoelectric element is composed of a laminated structure of a plurality of dielectric layers made of, for example, PZT (lead zirconate titanate) and electrode layers disposed between the plurality of dielectric layers. When an electric signal (voltage) is applied to the multilayer piezoelectric element, the displacement of the bending occurs in the stacking direction of each layer, that is, in the thickness direction.

  The input unit 40 receives an operation input from the user, and includes, for example, an operation button (operation key). In addition, when the panel 10 is a touch panel, the panel 10 can also accept the operation input from a user by detecting the contact from a user.

  The control unit 50 is a processor that controls the electronic device 1. The controller 50 applies a predetermined electrical signal (voltage corresponding to the audio signal) to the piezoelectric element 30. When the control unit 50 applies an electrical signal to the piezoelectric element 30, the piezoelectric element 30 causes a deflection displacement in the thickness direction. At this time, the panel 10 to which the piezoelectric element 30 is attached is deformed in accordance with the displacement of the piezoelectric element 30, and the panel 10 vibrates. For this reason, the panel 10 generates air conduction sound. In addition, the panel 10 transmits a human body vibration sound to an object in contact with the panel 10. Examples of the object include a part of the user's body (such as cartilage in the outer ear). For example, the control unit 50 can apply an electric signal corresponding to a voice signal related to the voice of the other party to the piezoelectric element 30 and generate air conduction sound and human body vibration sound corresponding to the voice signal. The audio signal may relate to a ringing melody or a music piece including music. Note that the audio signal applied to the electrical signal may be based on music data stored in the internal memory of the electronic device 1, or music data stored in an external server or the like is reproduced via a network. May be. The voltage applied to the piezoelectric element 30 by the control unit 50 is, for example, ± 15 V, which is higher than ± 5 V, which is an applied voltage of a so-called panel speaker for the purpose of conducting sound by air conduction sound instead of human body vibration sound. It may be. As a result, even when the user presses the panel 10 against his / her body with a force of 3N or more (5N to 10N), for example, the panel 10 is sufficiently vibrated, It is possible to generate a human body vibration sound through the section. Note that how much applied voltage is used can be appropriately adjusted according to the fixing strength of the panel 10 to the casing or the support member or the performance of the piezoelectric element 30.

  The panel 10 vibrates not only in the attachment region to which the piezoelectric element 30 is attached, but also in a region away from the attachment region. The panel 10 has a plurality of locations that vibrate in a direction intersecting the main surface of the panel 10 in the vibrating region, and the amplitude value of the vibration is increased from plus to minus with time in each of the plurality of locations. Or vice versa. At a certain moment, the panel 10 vibrates in such a manner that a portion having a relatively large vibration amplitude and a portion having a relatively small vibration amplitude are distributed randomly or periodically throughout the panel 10 at first glance. That is, vibrations of a plurality of waves are detected over the entire panel 10. Even when the user presses the panel 10 against his / her body with a force of, for example, 5N to 10N, the control unit 50 does not attenuate the piezoelectric element 30 in order to prevent the above-described vibration of the panel 10 from being attenuated. The applied voltage may be ± 15V. Therefore, the user can hear the sound by bringing his / her ear into contact with a region away from the above-described region where the panel 10 is attached.

  Here, the panel 10 may be approximately the same size as the user's ear. The panel 10 may be larger than the user's ear, as shown in FIG. In this case, when the user listens to the sound, the entire ear is easily covered with the panel 10 of the electronic device 1, so that it is difficult for ambient sounds (noise) to enter the ear canal. Panel 10 is an area wider than an area having a length corresponding to the distance from the lower leg of the anti-annulus (lower anti-limb) to the anti-tragus and a width corresponding to the distance from the tragus to the anti-annulus. Should just vibrate. The panel 10 preferably has a length corresponding to the distance between a portion near the upper leg of the ankle ring (upper pair leg) in the ear ring and the earlobe, and a distance between the tragus and a portion near the ear ring in the ear ring. It suffices that a region having a width corresponding to is vibrated. In this example, the length direction is the longitudinal direction 2a in which the panel 10 extends, and the piezoelectric element 30 is disposed closer to one end from the center. The width direction is a direction 2b orthogonal to the longitudinal direction. The region having such a length and width may be a rectangular region, or may be an elliptical shape having the above length as the major axis and the width as the minor axis. The average size of Japanese ears can be found by referring to the Japanese human body size database (1992-1994) created by the Human Life Engineering Research Center (HQL). If the panel 10 is larger than the average size of Japanese ears, the panel 10 is considered to be large enough to cover the entire foreign ear.

  By having the dimensions and shapes as described above, the panel 10 can cover the user's ears and is tolerant of misalignment when applied to the ears.

  The electronic device 1 can transmit air conduction sound and vibration sound through a part of the user's body (for example, cartilage of the outer ear) to the user by the vibration of the panel 10. Therefore, when outputting a sound having a volume equivalent to that of a conventional dynamic receiver, the sound transmitted to the periphery of the electronic device 1 due to the vibration of the air due to the vibration of the panel 10 is less than that of the dynamic receiver. Therefore, it is suitable, for example, when listening to a recorded message on a train or the like.

  In addition, since the electronic device 1 transmits vibration sound due to the vibration of the panel 10, even if the user wears an earphone or a headphone, for example, the user can contact the electronic device 1 with the earphone or the headphone so that the user can Sounds can be heard through headphones and body parts.

  The electronic device 1 transmits sound to the user by the vibration of the panel 10. Therefore, when the electronic device 1 does not include a separate dynamic receiver, it is not necessary to form an opening (sound outlet) for sound transmission in the housing, and the waterproof structure of the electronic device 1 can be simplified. In addition, when the electronic device 1 is provided with a dynamic receiver, the sound emission port is preferably closed by a member that allows gas to pass but not liquid. An example of the member that allows gas to pass but not liquid is Gore-Tex (registered trademark).

  FIG. 3 is a diagram showing a basic structure of the electronic apparatus 1 according to the embodiment of the present invention. 3A is a front view, and FIG. 3B is a cross-sectional view taken along the line bb in FIG. 3A. The electronic device 1 shown in FIG. 3 is a smartphone in which a touch panel, which is a glass plate, is arranged as a panel 10 on the front surface of a housing 60 (for example, a metal or resin case). The panel 10 is bonded to the housing 60 by the joining member 70 and is held by the housing 60. The panel 10 is partly attached to the housing 60 via a sheet member to be described later on the upper side of the electronic device 1. Here, the joining member 70 is, for example, an adhesive or a double-sided tape. The input unit 40 is also supported by the housing 60. The display unit 20 and the piezoelectric element 30 are attached to the panel 10 by a bonding member 70. Examples of the bonding member 70 suitable for attaching the piezoelectric element 30 to the panel 10 include an adhesive having a thermosetting property or an ultraviolet curable property, a double-sided tape, and the like. For example, a colorless and transparent acrylic ultraviolet curable adhesive is used. An optical elastic resin may be used. The panel 10, the display part 20, and the piezoelectric element 30 are each substantially rectangular.

  The display unit 20 is disposed approximately at the center in the short direction of the panel 10. The piezoelectric element 30 is provided at a predetermined distance from the end of the panel 10 in the longitudinal direction so that the longitudinal direction of the piezoelectric element 30 is along the short side of the panel 10 in the vicinity of the end. The display unit 20 and the piezoelectric element 30 are provided side by side in a direction parallel to the inner surface of the panel 10.

  The electronic device 1 according to the present embodiment has the above-described configuration, so that the panel 10 is deformed due to the deformation of the piezoelectric element 30 attached to the back surface of the panel 10, and the object that contacts the deformed panel 10. Air conduction sound and vibration sound can be transmitted to objects.

  FIG. 4 is a diagram illustrating an example of vibration of the panel 10 of the electronic device 1 according to the embodiment of the present invention. In the electronic device 1 according to this embodiment, the display unit 20 is attached to the panel 10. For this reason, the lower part of the panel 10 is less likely to vibrate than the upper part of the panel 10 to which the piezoelectric element 30 is attached. In other words, the upper portion of the panel 10 is directly bent by the piezoelectric element 30, and the vibration is attenuated at the lower portion as compared with the upper portion. The panel 10 is bent by the piezoelectric element 30 so that the portion directly above the piezoelectric element 30 protrudes higher than the surrounding area in the long-side direction 2a of the piezoelectric element 30. Therefore, vibration generated by the piezoelectric element 30 in the longitudinal direction 2a of the panel 10 can be attenuated. Therefore, sound leakage due to vibration of the lower portion of the panel 10 at the lower portion of the panel 10 can be reduced.

  In addition, the electronic device 1 transmits sound to the object by the vibration of the panel 10. Here, assuming that the piezoelectric element 30 is attached to the housing 60 and vibrates the housing 60, when the user picks up the electronic device and makes a call, the electronic device is vibrated by the vibration of the housing 60. (Normally, the user makes a call by holding the casing of the electronic device). On the other hand, such a problem hardly occurs in the electronic device 1 that vibrates the panel 10.

  By the way, the electronic device 1 according to the present embodiment is desired to further improve the sound pressure characteristics. Therefore, the present applicant examined the structure of the electronic device 1 that can further improve the sound pressure characteristics. Hereinafter, the structure of the electronic device 1 that has been studied will be described in detail.

  FIG. 5 is a cross-sectional view showing a detailed configuration of the electronic apparatus 1 according to the embodiment of the present invention. In the electronic device 1, a sheet member 80 is provided between the housing 60 and the panel 10. In the sheet member 80, a part of the sheet member 80 is joined to the panel 10, and another part different from the part is joined to the housing 60. Specifically, one end of the sheet member 80 is attached to the panel 10 via the joining member 70, and the other end opposite to the end in the extending direction of the sheet member 80 is the housing 60 via the joining member 70. Attached to. In addition, the piezoelectric element 30 is attached to the surface of the sheet member 80 opposite to the bonding surface with the panel 10 via the bonding member 70. In this configuration, the case where both ends of the sheet member 80 are attached to the panel 10 or the housing 60 is shown, but the attached region does not need to be an end, and a predetermined distance from the end. The present invention can be implemented even if a predetermined area separated by a distance is attached to the panel 10 or the housing 60. This is the same in the modified example described later.

  Here, the sheet | seat member 80 consists of a PET (Polyethylene terephthalate) film, an acrylic film, etc., for example, and thickness is about 0.05 mm. Such a sheet member 80 is easily deformed by an external force. For example, when an external force is applied in the thickness direction of the sheet member 80, bending deformation occurs in the direction of the external force.

  The sheet member 80 may be, for example, an elastic material such as rubber or silicone, a polyamide resin, or a film made of Gore-Tex (registered trademark) described above, in addition to a PET film or an acrylic film. Examples of the polyamide-based resin include Reny (registered trademark), which is made of a crystalline thermoplastic resin obtained from metaxylylenediamine and adipic acid and is rich in strength and elasticity. Such a polyamide-based resin may be a reinforced resin reinforced with glass fiber, metal fiber, carbon fiber, or the like using itself as a base polymer. The strength and elasticity are appropriately adjusted according to the amount of glass fiber, metal fiber, carbon fiber, or the like added to the polyamide-based resin. The reinforced resin as described above is formed, for example, by impregnating a resin into a base material formed by braiding glass fiber, metal fiber, carbon fiber, or the like and curing it. The reinforced resin may be formed by mixing a fiber piece finely cut into a liquid resin and then curing it. The reinforced resin may be a laminate of a base material in which fibers are knitted and a resin layer. Further, the sheet member 80 may be a metal plate widely used as a component of precision equipment, such as iron, stainless steel (iron-chromium alloy), and aluminum.

  The sheet member 80 includes a region A in which neither the panel 10 nor the housing 60 is attached between the region bonded to the panel 10 and the region bonded to the housing 60 in the sheet member 80. Have. The area A corresponds to the width indicated by the double arrow in FIG. The area A in the sheet member 80 is an area in which the sheet member 80 can be deformed (for example, bent and deformed). Accordingly, the region A in the sheet member 80 can be deformed following the deformation of the panel 10. Hereinafter, the area A is referred to as a deformation area A.

  The sheet member 80 is arranged so that the deformation area A of the sheet member 80 is substantially parallel to the panel 10. Therefore, the deformation area A is bent and deformed in a direction substantially parallel to the vibration (deformation) direction of the panel 10 (the panel 10 is deformed in a direction perpendicular to the main surface of the panel 10). Here, FIG. 6 shows a conventional structure in an electronic apparatus in which a piezoelectric element is attached to a panel. In the conventional structure, there is no sheet member between the housing 60 and the panel 10, and the housing 60 and the panel 10 are joined by the joining member 70 in the stacking direction thereof. The stacking direction of the housing 60 and the panel 10 is substantially the same as the vibration (deformation) direction of the panel 10 caused by the deformation of the piezoelectric element 30. Therefore, the deformation of the panel 10 is inhibited by joining the housing 60 and the panel 10 together. On the other hand, in the electronic device 1 according to the present invention in which the sheet member 80 is provided, the deformation region A of the sheet member 80 is flexed and deformed following the deformation when the panel 10 is deformed. hard. Thereby, the electronic device 1 according to the present invention can realize higher sound pressure characteristics by making it difficult to inhibit the deformation of the panel 10 as compared with the conventional electronic device. Here, the sheet member 80 is flexible to such an extent that it does not undergo fatigue failure even if the deformation following the vibration of the panel 10 is repeated.

  The piezoelectric element 30 is attached to the surface of the sheet member 80 opposite to the surface attached to the panel 10. At this time, when the panel 10 is viewed in plan, the sheet member 80 has a region where the region attached to the panel 10 and the region where the piezoelectric element 30 is attached in the sheet member 80 overlap at least. In other words, the panel 10, the sheet member 80, and the piezoelectric element 30 are laminated via the bonding member 70 in the bending direction of the piezoelectric element 30 (the vibration direction of the panel 10, that is, the direction perpendicular to the main surface of the panel 10). Has been. By having such a configuration, the force generated by the deformation (displacement) of the piezoelectric element 30 is efficiently propagated to the panel 10, and as a result, the sound pressure characteristics of the electronic device 1 are improved.

  By the way, in the electronic device 1 in which the piezoelectric element 30 is attached to the panel 10 as in the present invention, as described above, the panel 10 is positioned directly above the piezoelectric element 30 in the long side direction of the piezoelectric element 30. It has been found that the piezoelectric element 30 can be bent so as to protrude the highest. That is, the force generated by the deformation of the piezoelectric element 30 is most easily propagated directly above the piezoelectric element 30 in the panel 10. Therefore, it is important to improve the sound pressure characteristics that it is difficult to inhibit the vibration in the region immediately above and near the piezoelectric element 30 in the panel 10. Therefore, in the present invention, it is preferable to have a configuration in which the deformation region A of the sheet member 80 is provided in the vicinity of the piezoelectric element 30. On the other hand, as described above, since it is not preferable that the propagation of the force generated by the deformation of the piezoelectric element 30 is relaxed by the deformation area A, the deformation area A of the sheet member 80 is provided immediately above the piezoelectric element 30. Should be avoided. From the above viewpoint, in the electronic device 1 according to the present invention, the deformation region A () is adjacent to the region of the sheet member 80 where the panel 10 is attached or the region of the sheet member 80 where the piezoelectric element 30 is attached. Most preferably, a region in which neither the housing 60 nor the panel 10 is attached is formed.

  So far, as an example of the sheet member 80, a PET film, an acrylic film, or the like has been shown, but the material used for the sheet member is not limited thereto. For example, a double-sided tape for joining the members of the electronic device 1 may be used. In this case, a housing is provided between the region joined to the housing 60 and the region joined to the panel 10 in the double-sided tape. The present invention is realized as long as a configuration having a deformation region A to which neither the body 60 nor the panel 10 is attached is taken.

  FIG. 7 is a cross-sectional view showing the configuration of the present invention when a double-sided tape is used as the sheet member. In this configuration, two double-sided tapes having different lengths (a first double-sided tape 71 as a sheet member and a second double-sided tape for attaching the first double-sided tape 71 to the panel 10 are provided inside the electronic device 1. Tapes 72) are overlaid. In the first double-sided tape 71, a part of the double-sided tape 71 is joined to the panel 10 and another part different from the part is joined to the housing 60. Specifically, one end of the first double-sided tape 71 is attached to the panel 10 via the second double-sided tape 72, and the other end opposite to the end in the extending direction of the first double-sided tape 71. Is attached to the housing 60. In addition, the piezoelectric element 30 is attached to the surface of the first double-sided tape 71 opposite to the surface attached to the panel 10. In this configuration, since the double-sided tape is used as the sheet member, it is not necessary to separately provide a joining member for attaching the piezoelectric element to the double-sided tape. Therefore, the structure of the electronic device 1 can be simplified as compared with the case where a PET film or an acrylic film is used as the sheet member. Further, in this configuration, since the second double-sided tape 72 is interposed between the first double-sided tape 71 and the panel 10, the first double-sided tape is equal to the thickness of the second double-sided tape 72. 71 and the panel 10 are spaced apart. Since the separated distance is sufficiently larger than the maximum value of the amplitude when the panel 10 vibrates, the vibrated panel 10 can be prevented from coming into contact with the first double-sided tape 71.

  The first double-sided tape 71 is a deformation region in which neither the panel 10 nor the housing 60 is attached between the region bonded to the panel 10 and the region bonded to the housing 60 in the double-sided tape 71. A. Here, the first double-sided tape 71 has, for example, a structure in which a PET film is used as a base and the upper and lower surfaces of the film are covered with an adhesive, and can be easily deformed when an external force is applied. Therefore, since the deformation area A of the first double-sided tape 71 is deformed following the deformation when the panel 10 is deformed, the deformation of the panel 10 is hardly hindered and the sound pressure characteristics are improved.

  The first double-sided tape 71 has, for example, a three-layer structure in which the upper and lower surfaces of the PET base film are covered with an adhesive. Such a double-sided tape can form a non-adhesive region in which the adhesive is not coated on the double-sided tape, and the size of the non-adhesive region can be freely changed. Therefore, in this configuration, a region other than the region to which the panel 10, the housing 60, or the piezoelectric element 30 is attached in the first double-sided tape 71 can be set as a non-adhesive region (in FIG. In the double-sided tape 71, a non-adhesive region 71 (b) and other region 71 (a) are shown). By adopting such a configuration, the first double-sided tape 71 prevents the deformation areas A from touching and sticking to each other when the deformation area A is bent and deformed following the deformation of the panel 10. be able to.

  The configuration of the first double-sided tape 71 is not limited to the above configuration. For example, the base material sandwiched between the pressure-sensitive adhesives may be an acrylic film or the like in addition to the PET film, and may be a nonwoven fabric film or a foam. The double-sided tape of the foamed body is, for example, a double-sided tape formed by laminating an acrylic adhesive on the upper and lower surfaces of a polyethylene substrate having a structure having minute bubbles. Further, it is not always necessary to provide a non-adhesive region in the first double-sided tape 71.

  In the above-described configuration (FIG. 7) according to the present invention, the two double-sided tapes of the first double-sided tape 71 and the second double-sided tape 72 are used in an overlapping manner. There is no. A structure in which the first double-sided tape 71 as a sheet member is attached to the panel 10 without the second double-sided tape 72, that is, only the first double-sided tape 71 may be arranged. In such a case, the arrangement configuration of the double-sided tape inside the electronic device 1 can be simplified as compared with the case where two double-sided tapes are used in an overlapping manner. In addition, if a non-adhesive region is provided in the first double-sided tape 71, a deformation region A that is not attached to either the panel 10 or the housing 60 can be formed. An electronic device with improved characteristics can be configured.

  FIG. 8 is a diagram illustrating frequency characteristics of the electronic device according to the embodiment of the present invention. In FIG. 8, the frequency characteristic 91 of an electronic device (corresponding to FIG. 5) in which a PET film is disposed as the sheet member 80 between the housing 60 and the panel 10, and the first double-sided tape 71 is disposed as the sheet member 80. The frequency characteristic 92 of the manufactured electronic device (corresponding to FIG. 7) and the frequency characteristic 93 of the conventional electronic device (when no sheet member is provided; corresponding to FIG. 6) are shown. The horizontal axis represents the frequency of the output sound, and the vertical axis represents the sound pressure.

Conventionally, in an electronic device in which a piezoelectric element is attached to a panel, improvement of sound pressure in a low frequency band (for example, 300 Hz to 3.4 kHz) used in a voice call of a mobile phone, for example, 300 Hz to 1 kHz has been a problem. It was. Electronic device 1 according to the present invention
In the frequency band of about 300 Hz to 2.5 kHz, the frequency characteristics 91 and 92 in FIG. 1 indicate a sound pressure that is about 1 to 5 dB higher than the frequency characteristics 93 in the conventional electronic device, which is a conventional problem. The sound pressure in the low frequency band is improved.
This is because the electronic apparatus 1 according to the present invention has a structure that is difficult to inhibit the deformation of the panel 10. In addition, since there is almost no difference between the frequency characteristic 91 and the frequency characteristic 92, there is almost no difference in the influence on the sound pressure characteristic due to the material (PET film or double-sided tape) of the sheet member 80. Any material may be used as long as it is.

  In the above-described embodiment of the present invention, an example in which a substantially planar sheet member is provided as a member capable of bending deformation has been described, but the shape of the sheet member is not limited to a planar shape.

  FIG. 9 is a cross-sectional view showing a plurality of modified examples of the configuration of the present invention. In the present modification, a substantially L-shaped double-sided tape 70 (or 71) is disposed inside the electronic apparatus 1 as a sheet member. The double-sided tapes 70 and 71 have a shape bent substantially vertically so as to have a surface parallel to the panel 10 and a surface parallel to the housing 60 of the electronic device 1. As for the surface parallel to the panel 10 in the double-sided tapes 70 and 71, a part of the surface is bonded to the panel 10, while the surface parallel to the upper side surface of the electronic device 1 is bonded to the housing 60. Further, a deformation area A in which neither the panel 10 nor the housing 60 is attached is formed on the surface of the double-sided tape 70 or 71 parallel to the panel 10. The deformation area A is formed between the area bonded to the panel 10 in the double-sided tapes 70 and 71 and the area bonded to the housing 60. Since the deformation area A of the double-sided tapes 70 and 71 is deformed following the deformation when the panel 10 is deformed, it is difficult to inhibit the deformation of the panel 10 and the sound pressure characteristics are improved. At this time, the double-sided tapes 70 and 71 are arranged so that the deformation area A is substantially parallel to the panel 10. Accordingly, the deformation area A is bent and deformed in a direction substantially parallel to the vibration (deformation) direction of the panel 10.

  In the configuration shown in FIG. 9A, two double-sided tapes of a first double-sided tape 71 and a second double-sided tape 72 are used, and the first double-sided tape 71 is an end of a surface parallel to the panel 10. It has the shape which continued from the part and was bent substantially perpendicularly toward the back side of electronic equipment 1. In addition, the piezoelectric element 30 is attached to the surface of the first double-sided tape 71 opposite to the surface attached to the panel 10. In the first double-sided tape 71, the region other than the region where the panel 10, the casing 60, or the piezoelectric element 30 is attached is a non-adhesive region (71 (b)).

  FIG. 9B shows a configuration in which the edge of the panel 10 is covered with a bezel that is continuously provided on the housing 60 for the purpose of improving the impact resistance of the electronic device 1. In this configuration, the double-sided tape 70 as a sheet member has a substantially L shape having a surface parallel to the panel 10 and a surface parallel to the upper side surface of the electronic device 1. A surface of the double-sided tape 70 parallel to the upper surface of the electronic device 1 is attached to the housing 60 along the bezel of the housing 60. Further, the surface of the double-sided tape 70 parallel to the panel 10 extends outward from the panel 10, and the extended region is not joined to the housing 60, so that it can be deformed (deformable region A). ). In this configuration, the deformation area A is not covered by the panel 10, but is covered by the bezel of the housing 60, so that the double-sided tape 70 is not exposed and is not visually recognized. Also in this configuration, a non-adhesive region may be appropriately provided in the double-sided tape 70 as in the configuration of FIG.

  The configuration shown in FIG. 9C is a case where the double-sided tape as the sheet member and the double-sided tape for attaching the piezoelectric element 30 are integrated in the configuration of FIG. 9B. In such a case, the arrangement of the double-sided tape with respect to the electronic device 1 is simplified as compared with the configuration of FIG. 9B. For example, the piezoelectric element 30 is positioned closer to the upper side of the housing 60. Thus, the area where the display unit 20 can be arranged can be enlarged. In addition, when the piezoelectric element 30 is provided at a position close to the upper side surface of the housing 60, another member constituting the upper side surface of the housing 60 may be close to the piezoelectric element 30. In the electronic device 1 having such a configuration, the piezoelectric element 30 is brought into contact with other members such as corners and electronic parts protruding into the housing 60 due to an impact caused by dropping or the like, and the piezoelectric element 30 is damaged. There is a risk. Accordingly, the piezoelectric element 30 may be covered with a buffer member 90 made of a rubber molding material or the like, and an external force may be absorbed to reduce the propagation of impact to the piezoelectric element 30. 9C shows a configuration in which the surface of the piezoelectric element 30 other than the surface attached to the panel 10 is covered with the buffer member 90, the shape of the buffer member 90 is not limited to this, and a plate shape is used. The piezoelectric element 30 may be attached to a surface opposite to the surface attached to the panel 10. Alternatively, the buffer member 90 may be provided by dropping and solidifying an ultraviolet curable resin or the like on the surface of the piezoelectric element 30 opposite to the surface attached to the panel 10.

  FIG. 10 is a cross-sectional view showing a plurality of further modifications of the configuration of the present invention. This modification is a case where the deformation direction of the deformation area A of the double-sided tape 70 as the sheet member is substantially perpendicular to the vibration (deformation) direction of the panel 10 in the configuration shown in FIG. In this modification, the double-sided tape 70 as a sheet member has a substantially L-shape composed of a surface parallel to the panel 10 and a surface parallel to the upper side surface of the electronic device 1. A surface of the double-sided tape 70 parallel to the panel 10 is joined to the panel 10. On the other hand, a part of the surface parallel to the upper surface of the electronic device 1 is joined to the housing 60. Further, a deformation area A in which neither the panel 10 nor the housing 60 is attached is formed on a surface parallel to the upper surface of the electronic device 1 in the double-sided tape 70. The deformation area A is formed between the area bonded to the panel 10 and the area bonded to the housing 60 in the double-sided tape 70. Since the deformation area A of the double-sided tape 70 is deformed following the deformation when the panel 10 is deformed, it is difficult to inhibit the deformation of the panel 10 and the sound pressure characteristics are improved. At this time, the double-sided tape 70 is arranged so that the deformation area A is substantially perpendicular to the panel 10. Accordingly, the deformation area A is bent and deformed in a direction substantially perpendicular to the vibration (deformation) direction of the panel 10.

  In the present invention, the sheet member 80 can be arranged so that the deformation region A of the sheet member 80 is in any direction parallel to the deformation (vibration) direction of the panel 10 and a direction perpendicular to the direction. That is, the arrangement direction of the deformation area A is not limited in the present invention. Therefore, the degree of freedom of arrangement of the sheet member in the electronic device 1 is high.

  In the configuration shown in FIG. 10A, a double-sided tape as a sheet member and a double-sided tape for attaching the piezoelectric element 30 are separately provided. By having such a configuration, the propagation of force generated by the deformation of the piezoelectric element 30 is not relaxed by the deformation area A of the double-sided tape 70.

  The configuration shown in FIG. 10B is a case where a double-sided tape as a sheet member and a double-sided tape for attaching the piezoelectric element 30 are integrated. In such a case, the arrangement configuration of the double-sided tape with respect to the electronic device 1 can be simplified as compared with the case where the double-sided tape as the sheet member and the double-sided tape for attaching the piezoelectric element 30 are separately provided.

  FIG. 11 is a diagram for explaining cross-sectional structures at different positions in the short-side direction of the main surface of the electronic apparatus 1. FIG. 11A shows a substantially L-shaped sheet member (double-sided tape 71) provided inside the electronic apparatus 1. A double-sided tape 71 shown in FIG. 11A has, for example, a surface attached to the panel 10 and a surface attached to the housing 60 in the same manner as the configuration of FIG. The surface attached to the panel 10 includes a side 11a parallel to the short side of the panel 10 (that is, the short side of the main surface of the electronic device 1) and the long side of the panel 10 (that is, the long side of the main surface of the electronic device 1). ) Is a substantially rectangular surface. The surface attached to the housing 60 is a substantially rectangular surface including a side 11 c parallel to the short side of the main surface of the electronic device 1 and a side 11 d parallel to the thickness direction of the electronic device 1. The length of the side 11 c on the surface attached to the housing 60 is shorter than the length of the side 11 a on the surface attached to the panel 10. Further, a non-adhesive region 71 (b) having a width shorter than the side 11 c of the surface attached to the housing 60 is formed on the surface attached to the panel 10. The non-adhesive region 71 (b) is formed on the surface opposite to the surface attached to the panel 10. Therefore, this region is not joined to the housing 60.

  FIG.11 (b) is sectional drawing along the XX line in Fig.11 (a). In FIG. 11B, not only the double-sided tape 71 but also members constituting the electronic device 1 are illustrated. In FIG. 11B, a surface of the double-sided tape 71 parallel to the panel 10 is attached to the panel 10, while a surface opposite to the surface attached to the panel 10 is attached to the housing 60.

  FIG.11 (c) is sectional drawing along the YY line in FIG.11 (c) (The member which comprises not only the double-sided tape 71 but the electronic device 1 is also shown in figure). In FIG. 11C, the surface parallel to the panel 10 of the double-sided tape 71 is attached to the panel 10, while the surface opposite to the surface attached to the panel 10 is attached to the housing 60. Furthermore, a surface that is bent and extended from a surface parallel to the panel 10 and parallel to the upper surface of the electronic device 1 is also attached to the housing 60. In such a case, it is possible to attach the panel 10 and the housing | casing 60 more firmly than the structure shown in FIG.11 (b) (XX cross section).

  FIG.11 (d) is sectional drawing along the ZZ line in FIG.11 (c) (The member which comprises not only the double-sided tape 71 but the electronic device 1 is also shown in figure). In FIG.11 (d), although the surface parallel to the panel 10 in the double-sided tape 71 is attached to the panel 10, the surface on the opposite side to the surface attached to the panel 10 is a non-adhesion area | region (71 (b)). Therefore, it is not attached to the housing 60. On the other hand, a surface that is bent and extended from a surface parallel to the panel 10 and is parallel to the upper surface of the electronic device 1 is attached to the housing 60. Here, the surface parallel to the upper surface of the electronic device 1 in the double-sided tape 71 is not the entire region of the surface attached to the housing 60, but the non-adhesive region (71 (b)) of the double-sided tape 71. A region corresponding to the thickness width of the non-adhesive layer is not attached to the housing 60. Here, the non-adhesive layer is a layer formed of the adhesive when the intermediate layer of the double-sided tape 71 is coated with the adhesive, and the thickness width of the non-adhesive layer is formed of the adhesive. The thickness width of the layer to be formed is shown. In the cross section along the ZZ line, compared to the cross section along the YY line, the surface of the double-sided tape 71 opposite to the surface attached to the panel 10 is not covered with the adhesive. The double-sided tape 71 becomes thinner by the thickness width of the layer to be formed. Therefore, in the cross section along the line ZZ, the double-sided tape 71 is not covered with the adhesive and is separated from the housing 60 by the amount of the reduced thickness. The width A at which the double-sided tape 71 is separated from the housing 60 corresponds to the width of the region of the double-sided tape 71 that is not attached to the housing 60 on the surface parallel to the upper surface of the electronic device 1. This region is the deformation region A, and is deformed following the deformation when the panel 10 is deformed. Therefore, the deformation of the panel 10 is hardly inhibited and the sound pressure characteristics are improved.

  As described above, the configuration of the double-sided tape 71 in the cross-sectional structure of the electronic device 1 is at least three (FIGS. 11B to 11D). The area occupied by each of these three structures, that is, the cross-sectional structures along the XX line, the YY line, and the ZZ line, in the short side direction of the main surface of the electronic device 1 is a double-sided tape 71. It is possible to adjust as appropriate by changing the shape. For example, the fixing strength between the panel 10 and the housing 60 by the double-sided tape 71 can be adjusted by adjusting the width of the side 11c with respect to the side 11a. Further, if the width of the side 11e (the width of the deformation region A in the short side direction of the main surface of the electronic device 1) with respect to the side 11a is increased (that is, the width of the non-adhesive region is increased), the sound pressure characteristics are improved. Can be made.

  Here, in the electronic device 1 according to the present invention, when the fixing strength with the casing 60 at the left and right end portions (the end portion on the short side of the panel 10) is low, the left and right end portions of the panel 10 vibrate greatly. . At this time, depending on the frequency of the drive signal, the vibration may occur in the opposite phase to the vibration of the piezoelectric element 30, and the sound pressure characteristics of the electronic device 1 may be degraded. Therefore, in the present invention, the panel 10 and the housing 60 are firmly fixed by the double-sided tape 71 at the left and right ends of the panel 10, and the non-adhesive region is provided on the double-sided tape 71 other than the left and right ends. It is desirable to form the deformation area A. Note that the deformation area A in the double-sided tape 71 as the sheet member can be changed in the width direction of the area in the short side direction of the panel 10 as described above. Thus, both the improvement of the sound pressure characteristics due to the provision of the deformation area A and the improvement of the sound pressure characteristics due to the fixing to the housing 60 without providing the deformation area A at the left and right ends of the panel 10 are achieved. be able to. Further, in order to firmly fix the left and right end portions of the panel 10 by the housing 60, for example, an adhesive having an adhesive strength higher than that of the double-sided tape 71 is applied on the double-sided tape 71 and fixed by the adhesive. It is good also as a structure. Further, instead of applying an adhesive on the double-sided tape 71, a part of the double-sided tape 71 is pulled out, the formed space is filled with the adhesive, and the panel 10 and the housing 60 are fixed. Also good. The adhesive used here is, for example, a non-heating type curable adhesive, or a moisture curable elastic adhesive that cures by reacting with moisture (humidity) in the air. The moisture-curing elastic adhesive has, for example, a special polymer containing a silyl group as a main component.

  FIG. 12 is a cross-sectional view showing the configuration of the present invention when a scattering prevention sheet is used as the sheet member. The scattering prevention sheet 110 is a member provided to prevent the glass panel fragments from scattering due to an impact on the electronic device 1. The scattering prevention sheet 110 is attached to the inner surface of the electronic device 1 in the panel 10 via a colorless and transparent adhesive or the like. The display unit 20 is attached to the surface of the anti-scattering sheet 110 opposite to the surface attached to the panel 10 via a colorless transparent adhesive or the like, and the piezoelectric element 30 is attached via a double-sided tape or the like. It is attached. Furthermore, the region located on the upper side of the electronic device 1 in the anti-scattering sheet 110 is attached to the housing 60 via a double-sided tape or the like.

  The scattering prevention sheet 110 has a part of the region that is not attached to the panel 10 on the upper side of the electronic device 1. The anti-scattering sheet 110 includes a region where neither the panel 10 nor the housing 60 is attached between the region attached to the panel 10 and the region attached to the housing 60, that is, the deformation region A. Have. Since the deformation area A is deformed following the deformation when the panel 10 is deformed, the deformation of the panel 10 is hardly hindered and the sound pressure characteristics are improved.

  Although FIG. 12 shows the case where the scattering prevention sheet 110 is used as the sheet member, a touch panel may be provided instead of the scattering prevention sheet 110. The touch panel is obtained by forming a transparent conductive film layer such as indium tin oxide on the surface of a plastic film by sputtering, for example. Since the touch panel uses a flexible plastic film as a base material, the touch panel can be bent and deformed. Therefore, the touch panel can be deformed following the deformation of the panel 10 by providing a deformation region.

  So far, the configuration in which the sheet member 80 is provided in the electronic device in which the piezoelectric element 30 is attached to the panel 10 has been described. However, the present invention is not limited to such a configuration. The present invention can be realized even in a configuration in which the sheet member 80 is provided in the electronic device to which the piezoelectric element 30 is attached.

  FIG. 13 is a cross-sectional view showing a configuration in which the piezoelectric element 30 is attached to the housing 60 in the embodiment of the present invention. The housing 60 includes a rear case (first housing portion) 61 and a cover member (second housing portion) 62 that is detachable from the rear case 61. The cover member 62 is, for example, a battery cover made of polycarbonate. The panel 10 is attached to the rear case 61. The display unit 20 and the input unit 40 are also attached to the rear case 61 (not shown). The piezoelectric element 30 is attached to the surface of the cover member 62 on the inner side of the electronic device 1 via the sheet member 80. The cover member 62 to which the piezoelectric element 30 is attached is deformed according to the displacement of the piezoelectric element 30 and vibrates. For this reason, the cover member 62 generates air conduction sound. Further, the cover member 62 transmits the human body vibration sound to the object that contacts the cover member 62.

  In the sheet member 80, a part of the sheet member 80 is joined to the cover member 62 via the joining member 70, and another part different from the part is joined to the rear case 61 via the joining member 70. The seat member 80 is a deformation in which neither the cover member 62 nor the rear case 61 is attached between the region attached to the cover member 62 and the region attached to the rear case 61 in the sheet member 80. It has area A. Since the deformation area A is deformed following the deformation when the cover member 62 is deformed, the deformation of the cover member 62 is hardly hindered and the sound pressure characteristics are improved.

  Although the present invention has been described based on the drawings and embodiments, it should be noted that those skilled in the art can easily make various changes and modifications based on the present disclosure. Therefore, it should be noted that these variations and modifications are included in the scope of the present invention. For example, in a double-sided tape as a sheet member, a non-adhesive region was provided on a base material such as a PET film by not covering the adhesive, but the present invention is not limited to this, and on the region where the adhesive is disposed. It is also possible to provide the non-adhesive region by coating fine powder composed of an organic substance, an inorganic substance, or an organic-inorganic composite, or by covering a plastic sheet or the like that does not have adhesiveness. Moreover, although the example in which the double-sided tape as a sheet | seat member was used was shown as a modification of this invention, it is clear that a PET film, an acrylic film, etc. may be used instead of a double-sided tape. Moreover, although the joining member for attaching the display unit 20 to the panel 10 and the joining member for attaching the piezoelectric element 30 to the panel 10 are shown separately, the present invention is not limited to this, The joining member may be integrated with the electronic device 1. Moreover, although the structure which uses a double-sided tape was demonstrated for joining to the sheet | seat member 80 and the panel 10 or the housing | casing 60, it is not limited to this, You may use an adhesive, an adhesive agent, etc. Moreover, although the embodiment of the present invention has been described by taking a smartphone as an example, the present invention can be realized even with a foldable mobile phone.

  The electronic device 1 according to the present invention has the following features.

  In the electronic apparatus 1, the panel 10 has one end of the panel 10 attached to the casing 60 by a joining member 70, while the other end opposite to the one end of the panel 10 is connected to the casing via a sheet member. In addition, the sheet member 80 has a part of the sheet member 80 bonded to the panel 10, while the other part different from the part is bonded to the housing 60. The fixing strength between the other end and the housing 60 is lower than the fixing strength between the one end of the panel 10 and the housing 60.

DESCRIPTION OF SYMBOLS 1 Electronic device 10 Panel 20 Display part 30 Piezoelectric element 40 Input part 50 Control part 60 Case 61 Rear case 62 Cover member 70 Joining member 71 1st double-sided tape 72 2nd double-sided tape 80 Sheet | seat member 90 Buffer member 110 Scatter prevention Sheet

Claims (7)

A housing,
A panel held in the housing;
A piezoelectric element attached to the panel;
Due to the deformation of the piezoelectric element, the panel is deformed, and is an electronic device that transmits a human body vibration sound to an object in contact with the panel,
A sheet member is provided between the housing and the panel,
The sheet member has a part of the sheet member joined to the panel, and another part different from the part is joined to the housing,
Wherein the sheet member, between said portion and said another portion, have a region which none have attached the panel and the housing,
The piezoelectric element is attached to the surface of the sheet member opposite to the surface attached to the panel,
An electronic apparatus comprising: an area where the area of the sheet member to which the panel is attached and the area of the sheet member to which the piezoelectric element is attached overlap at least when the panel is viewed in plan . An area where neither the casing nor the panel of the sheet member is attached is formed adjacent to an area of the sheet member where the panel is attached or an area of the sheet member where the piezoelectric element is attached. Has been
The electronic device according to claim 1. A housing,
A panel held in the housing;
A piezoelectric element attached to the panel;
Due to the deformation of the piezoelectric element, the panel is deformed, and is an electronic device that transmits a human body vibration sound to an object in contact with the panel,
A sheet member is provided between the housing and the panel,
The sheet member has a part of the sheet member joined to the panel, and another part different from the part is joined to the housing,
In the sheet member, between the part and the other part, there is a region where neither the panel nor the housing is attached,
The sheet member is a touch panel.
An electronic device characterized by that. A housing,
A panel held in the housing;
A piezoelectric element attached to the panel;
Due to the deformation of the piezoelectric element, the panel is deformed, and is an electronic device that transmits a human body vibration sound to an object in contact with the panel,
A sheet member is provided between the housing and the panel,
The sheet member has a part of the sheet member joined to the panel, and another part different from the part is joined to the housing,
In the sheet member, between the part and the other part, there is a region where neither the panel nor the housing is attached,
The sheet member is a scattering prevention sheet for preventing scattering of glass constituting the panel.
An electronic device characterized by that. The region of the sheet member is deformed following the deformation of the panel.
The electronic apparatus according to claim 1, wherein the electronic apparatus is an electronic apparatus. The region of the sheet member is deformed in a direction parallel to the vibration direction of the panel.
The electronic device according to claim 5, wherein: The region of the sheet member is deformed in a direction perpendicular to the vibration direction of the panel.
The electronic device according to claim 5, wherein:

Images