JP7234594B2 - Vibration device and electronic equipment - Google Patents

Description

One aspect of the present invention relates to vibration devices and electronic equipment.

A piezoelectric device is known that includes a piezoelectric element, a vibrating member to which the piezoelectric element is bonded, and a wiring member electrically connected to the piezoelectric element (for example, Patent Document 1). The wiring member has one end connected to the end face of the vibrating member and the other end connected to an electronic device on which the vibrating device is mounted. One end of the wiring member is physically connected to the diaphragm and electrically connected to the piezoelectric element. The other end of the wiring member is electrically and physically connected to a connector, for example.

JP-A-04-070100

In the vibrating device described in Patent Document 1, the reliability of the vibrating device may deteriorate as follows. Since one end of the wiring member is physically connected to the vibrating member, vibration is transmitted from the vibrating member. Since the other end of the wiring member is physically connected to the external device, it is less likely to vibrate. Therefore, when the vibrating member vibrates, a mechanical load acts on the connecting portion between one end of the wiring member and the vibrating member. When a mechanical load acts on the connecting portion, there is a possibility that the connecting strength between the wiring member and the vibrating member is lowered. When the connection strength between the wiring member and the vibration member is lowered, for example, the wiring member and the vibration member may become separated, and the electrical connection between the piezoelectric element and the wiring member may be interrupted.

An object of one aspect of the present invention is to provide a vibrating device whose electrical reliability is less likely to deteriorate.

A vibrating device according to one aspect of the present invention includes a vibrating portion having a piezoelectric element, and a wiring member electrically connected to the piezoelectric element. The piezoelectric body has an internal electrode disposed inside and an external electrode electrically connected to the internal electrode, and the piezoelectric body includes a first main surface and a second main surface facing each other, and a second main surface. a side surface adjacent to each of the one main surface and the second main surface and extending in a direction opposite to the first main surface and the second main surface, and the external electrode is arranged on the first main surface. The wiring member has a first region located on the external electrode and joined to the external electrode, a second region joined to the first main surface, and a region between the first region and the second region. a third region located therebetween and spaced from the first major surface.

In the one aspect described above, the wiring member has a second region bonded to the first main surface of the piezoelectric element in addition to the first region bonded to the external electrode. Therefore, even when the vibrating device vibrates, a mechanical load is less likely to act on the joint between the first region and the external electrode. Therefore, separation between the first region and the external electrode is less likely to occur.

Furthermore, the wiring member has a third region located between the first region and the second region and spaced from the first main surface of the piezoelectric body. Therefore, for example, even when the first region and the external electrode are joined with a conductive joining member and the second region and the first main surface of the piezoelectric element are joined with an insulating joining member, the third region provides insulation. A gap is secured between the conductive joining member and the conductive joining member. This prevents the insulating joining member from pushing the conductive joining member away and entering between the first region and the external electrode, resulting in poor conduction.

As described above, according to the one aspect, the electrical connection between the external electrodes and the wiring members is ensured. Therefore, the electrical reliability of the vibrating device is less likely to deteriorate.

In the above aspect, the first main surface has a rectangular shape, and the wiring member extends along the long sides of the first main surface and extends along the short sides of the first main surface when viewed from the opposing direction. The second region may intersect with the side and be joined to one end in the long side direction of the first main surface. In this case, since the first main surface has a rectangular shape, the amount of displacement of the piezoelectric element is greatest at the center in the long side direction of the first main surface, and is highest at both ends in the long side direction of the first main surface. become smaller. Therefore, the amount of displacement of the second region is smaller than when the second region is joined to the ends in the short side direction of the first main surface. In the wiring member, the external region connected to the second region on the side opposite to the third region tends to be displaced with the displacement of the second region, but the vibration of the external region coincides with the vibration of the piezoelectric element. However, the vibration of the piezoelectric element may be disturbed. In the one aspect described above, since the amount of displacement of the second region is relatively small, the displacement of the external region connected to the second region is suppressed. Therefore, the vibration of the piezoelectric element is less likely to be disturbed, and the amplitude of the piezoelectric element can be increased.

In the aspect described above, the wiring member further has a fourth region supported by the supporting portion and a fifth region located between the second region and the fourth region, and The distance between the first region and the second region in may be shorter than the distance between the second region and the fourth region in the long side direction. In this case, the third area can easily deform following the vibration of the piezoelectric element, and the distortion of the wiring member can be concentrated on the play of the fifth area. Therefore, the amplitude of the piezoelectric element can be increased.

The one aspect may further include holding portions that hold both end portions of the vibrating portion in the long-side direction of the first main surface. In this case, it is possible to further increase the amplitude at the central portion in the long side direction of the vibrating portion.

In the one aspect described above, the distance between the second region and the first main surface in the opposing direction may gradually increase as the second region separates from the third region. In this case, compared to the case where the distance between the second region and the first main surface is the same as the distance between the third region and the first main surface, the distance between the second region and the first main surface The volume of the joint member provided can be increased. Thereby, in the wiring member, the vibration of the external region connected to the second region on the side opposite to the third region is easily absorbed. Therefore, the vibration of the piezoelectric element is less likely to be disturbed, and the amplitude of the piezoelectric element can be further increased.

The one aspect described above may further include a joining member joining the second region to the first main surface, and the joining member may have a side portion provided on the side surface. In this case, since the bonding members are provided not only on the first main surface but also on the side surfaces, the bonding strength between the second region and the piezoelectric body is improved. As a result, even when the vibrating device vibrates, a mechanical load is less likely to act on the joint between the first region and the external electrode. Therefore, separation between the first region and the external electrode is more difficult to occur.

In the one aspect described above, the maximum distance between the first main surface and the second region in the facing direction may be larger than the maximum distance between the first main surface and the first region in the facing direction. In this case, the wiring member is easily deformed smoothly, and the amplitude of the piezoelectric element can be increased more effectively.

In the one aspect described above, the vibrating section may further include a vibrating member to which the piezoelectric element is joined. In this case, vibration of the piezoelectric element can be increased.

In one aspect described above, the external electrode may be arranged in the central portion of the first main surface. In this case, the piezoelectric element can be vibrated in a well-balanced manner.

An electronic device according to one aspect of the present invention includes the vibration device described above.

In the one aspect, since the vibrating device is provided, the electrical reliability is less likely to deteriorate.

ADVANTAGE OF THE INVENTION According to one aspect of this invention, the vibration device and electronic equipment which provide the vibration device which electric reliability is hard to fall can be provided.

1 is a perspective view of a vibration device according to an embodiment; FIG. 2 is an exploded perspective view of the vibration device of FIG. 1; FIG. FIG. 2 is a cross-sectional view along line III-III of FIG. 1; 4 is a cross-sectional view showing an enlarged part of FIG. 3; FIG. 3 is an exploded perspective view showing the configuration of a piezoelectric element; FIG. FIG. 4 is a top view of the connection structure and the piezoelectric element; It is a bottom view of a connection structure. It is a partially enlarged cross-sectional view of a vibrating device according to a modification.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. In the description, the same reference numerals are used for the same elements or elements having the same functions, and overlapping descriptions are omitted.

FIG. 1 is a perspective view of a vibration device according to an embodiment. 2 is an exploded perspective view of the vibration device of FIG. 1. FIG. FIG. 3 is a cross-sectional view along line III--III in FIG. 4 is a cross-sectional view showing an enlarged part of FIG. 3. FIG. As shown in FIGS. 1 to 4, the vibrating device 100 includes a vibrating portion 1, a connection structure 2 connected to the vibrating portion 1, and a case 3 in which the vibrating portion 1 is arranged. Vibration device 100 is used, for example, as a speaker or a buzzer. The vibration device 100 is provided in electronic devices such as televisions and smartphones.

The case 3 is made of, for example, a resin material such as acrylic resin, vinyl chloride resin, molding resin, or the like. The case 3 is, for example, a rectangular parallelepiped box member with an open top. The case 3 has a rectangular plate-shaped bottom portion 3a, a pair of side portions 3b facing each other, and a pair of side portions 3c facing each other.

The bottom portion 3a has a rectangular shape having a pair of long sides and a pair of short sides when viewed in the thickness direction. Rectangular shapes include, for example, shapes with chamfered corners and shapes with rounded corners. Hereinafter, the long side direction of the bottom portion 3a is the X direction, the short side direction of the bottom portion 3a is the Y direction, and the thickness direction of the bottom portion 3a is the Z direction.

The length of the bottom portion 3a in the X direction is, for example, 33 mm. The length of the bottom portion 3a in the Y direction is, for example, 18 mm. The length of the bottom portion 3a in the Z direction is, for example, 1.5 mm. A rectangular concave portion 3d is formed in the central portion of the upper surface of the bottom portion 3a as viewed from the Z direction. The length of the concave portion 3d in the X direction is, for example, 15 mm. The length of the recess 3d in the Y direction is, for example, 10 mm. The length (depth) of the concave portion 3d in the Z direction is, for example, 1.0 mm.

The pair of side portions 3b has a rectangular plate shape and extends along the Z direction from the long side portions of the bottom portion 3a. The facing direction of the pair of side portions 3b coincides with the Y direction. One side portion 3b is formed with a rectangular through-hole 3e penetrating through the side portion 3b in the thickness direction (Y direction). In FIG. 3, illustration of the through hole 3e is omitted. Sound generated by the vibrating device 100 is transmitted to the outside of the case 3 mainly through the through holes 3e. The pair of side portions 3c has a rectangular plate shape and extends along the Z direction from the short sides of the bottom portion 3a. The facing direction of the pair of side portions 3c coincides with the X direction. The lengths of the sides 3b and 3c in the Z direction are the same, for example 7.6 mm.

The case 3 further has a support portion 3f that supports the connecting structure 2. As shown in FIG. The support portion 3f protrudes outward from the case 3 along the X direction from the end portion of the one side portion 3c opposite to the bottom portion 3a.

The vibrating portion 1 is arranged on the bottom portion 3a. In this embodiment, the vibrating portion 1 is surrounded by a pair of side portions 3b and a pair of side portions 3c on the bottom portion 3a. The vibrating section 1 is housed in the case 3 . The vibration section 1 has a piezoelectric element 10 and a vibration member 12 joined to the piezoelectric element 10 .

The vibrating member 12 is made of metal such as Ni--Fe alloy, Ni, brass, or stainless steel. In this embodiment, the vibrating member 12 is a plate-like member. The vibrating member 12 has a pair of main surfaces 12a and 12b facing each other in the Z direction. The vibrating member 12 is arranged so that the outer edge of the vibrating member 12 is positioned outside the outer edge of the recess 3d when viewed from the Z direction. The vibrating member 12 completely covers the recess 3d.

The main surface 12b faces the bottom portion 3a in the Z direction. The main surface 12b is joined (adhered) to the bottom portion 3a by an adhesive layer 60 made of, for example, epoxy resin or acrylic resin. The adhesive layer 60 does not contain a conductive filler and has electrical insulation. The main surface 12b is joined to the periphery of the recess 3d in the bottom 3a and supported by the periphery of the recess 3d.

In other words, the bottom portion 3a connects both ends 1a of the vibrating portion 1 in the long side direction (X direction) of the main surface 12a and both ends 1b of the vibrating portion 1 in the short side direction (Y direction) of the main surface 12a. It functions as a holding part that holds. In this embodiment, the end portion 1a is the end portion of the vibrating member 12 in the long side direction (X direction), and the end portion 1b is the end portion of the vibrating member 12 in the short side direction (Y direction). Bottom 3a may not hold both ends 1b.

Each principal surface 12a, 12b has a rectangular shape with a pair of long sides and a pair of short sides. That is, the vibrating member 12 has a rectangular shape having a pair of long sides and a pair of short sides in a plan view (as viewed in the Z direction). In this embodiment, the long side direction of each of the main surfaces 12a and 12b matches the X direction. The direction of the short side of each main surface 12a, 12b coincides with the Y direction.

The length of the vibrating member 12 in the X direction is, for example, 30 mm. The length of the vibrating member 12 in the Y direction is, for example, 15 mm. The length of the vibrating member 12 in the Z direction is, for example, 100 μm.

The piezoelectric element 10 has a piezoelectric body 11 and a plurality of external electrodes 13 and 15 . In this embodiment, the piezoelectric element 10 has two external electrodes 13 and 15 . The external electrodes 13 and 15 have different polarities.

The piezoelectric element 11 has a rectangular parallelepiped shape. The rectangular parallelepiped shape includes, for example, a rectangular parallelepiped shape with chamfered corners and edges, and a rectangular parallelepiped shape with rounded corners and edges. The piezoelectric body 11 has a pair of main surfaces 11a and 11b (a first main surface and a second main surface) and a side surface 11e. The pair of main surfaces 11a and 11b are opposed to each other in the Z direction. That is, the facing direction of the pair of main surfaces 11a and 11b is the Z direction. The facing direction of the pair of main surfaces 11a and 11b is also the orthogonal direction orthogonal to each of the pair of main surfaces 11a and 11b.

The side surface 11e is adjacent to each of the pair of main surfaces 11a and 11b. It extends in the facing direction of the pair of main surfaces 11a and 11b. In this embodiment, the piezoelectric element 11 has four side surfaces 11e. Each side surface 11e connects the principal surface 11a and the principal surface 11b to each other. The main surface 11b faces the main surface 12a in the Z direction. The main surface 11b is joined (adhered) to the central portion of the main surface 12a by an adhesive layer 61 .

Each main surface 11a, 11b has a rectangular shape. Each principal surface 11a, 11b has a rectangular shape with a pair of long sides 11c and a pair of short sides 11d. That is, the piezoelectric element 10 (piezoelectric body 11) has a rectangular shape having a pair of long sides and a pair of short sides in a plan view (as seen from the Z direction). In this embodiment, the long-side direction of each of the main surfaces 11a and 11b matches the X direction. The short side direction of each of the main surfaces 11a and 11b matches the Y direction.

The length of the piezoelectric body 11 in the X direction is, for example, 20 mm. The length of the piezoelectric body 11 in the Y direction is, for example, 10 mm. The length of the piezoelectric body 11 in the Z direction is, for example, 200 μm.

FIG. 5 is an exploded perspective view showing the configuration of the piezoelectric element. As shown in FIGS. 4 and 5, the piezoelectric body 11 is constructed by stacking a plurality of piezoelectric layers 17a, 17b, 17c, and 17d. That is, the piezoelectric body 11 has a plurality of stacked piezoelectric layers 17a, 17b, 17c, and 17d. In this embodiment, the piezoelectric body 11 has four piezoelectric layers 17a, 17b, 17c, and 17d. In the piezoelectric body 11, the direction in which the plurality of piezoelectric layers 17a, 17b, 17c, and 17d are laminated coincides with the Z direction. The piezoelectric layer 17a has a main surface 11a. The piezoelectric layer 17d has a main surface 11b. The piezoelectric layers 17b and 17c are located between the piezoelectric layers 17a and 17d.

Each piezoelectric layer 17a, 17b, 17c, 17d is made of a piezoelectric material. In this embodiment, each piezoelectric layer 17a, 17b, 17c, 17d is made of a piezoelectric ceramic material. Piezoelectric ceramic materials include, for example, PZT[Pb(Zr,Ti) _O3 ], PT( _PbTiO3 ), PLZT[(Pb,La)(Zr,Ti) _O3 ], or barium titanate ( _BaTiO3 ). is used. Each of the piezoelectric layers 17a, 17b, 17c, and 17d is composed of, for example, a sintered ceramic green sheet containing the piezoelectric ceramic material described above. In the actual piezoelectric body 11, the piezoelectric layers 17a, 17b, 17c and 17d are integrated to such an extent that the boundaries between the piezoelectric layers 17a, 17b, 17c and 17d cannot be recognized.

The piezoelectric element 10 has a plurality of internal electrodes 19 , 21 , 23 arranged inside the piezoelectric body 11 . In this embodiment, the piezoelectric element 10 has three internal electrodes 19 , 21 , 23 . Each internal electrode 19, 21, 23 is made of a conductive material. Ag, Pd, or Ag--Pd alloy is used for the conductive material, for example. Each of the internal electrodes 19, 21, 23 is configured, for example, as a sintered body of a conductive paste containing the conductive material. In this embodiment, the outer shape of each internal electrode 19, 21, 23 is rectangular.

The internal electrodes 19, 21, 23 are arranged at different positions (layers) in the Z direction. The internal electrode 19 and the internal electrode 21 face each other with a gap in the Z direction. The internal electrode 21 and the internal electrode 23 face each other with a gap in the Z direction. The internal electrode 19 is positioned between the piezoelectric layers 17a and 17b. The internal electrode 21 is positioned between the piezoelectric layer 17b and the piezoelectric layer 17c. The internal electrode 23 is positioned between the piezoelectric layer 17c and the piezoelectric layer 17d. Each internal electrode 19 , 21 , 23 is not exposed on the surface of the piezoelectric body 11 . That is, the internal electrodes 19, 21, 23 are not exposed on the side surfaces 11e. Each of the internal electrodes 19, 21, 23 is separated from all edges (four sides) of the main surfaces 11a, 11b when viewed in the Z direction.

A plurality of external electrodes 13 and 15 are arranged on main surface 11a. The external electrodes 13 and the external electrodes 15 are arranged in the X direction. The external electrodes 13 and 15 are adjacent to each other in the X direction. A plurality of external electrodes 13 and 15 are arranged in the central portion of main surface 11a. The plurality of external electrodes 13 and 15 are separated from all edges (four sides) of the main surface 11a when viewed in the Z direction. Each of the external electrodes 13 and 15 has a rectangular shape when viewed from the Z direction. Each external electrode 13, 15 is made of a conductive material. Ag, Pd, or Ag--Pd alloy is used for the conductive material, for example. Each of the external electrodes 13 and 15 is configured as, for example, a sintered body of a conductive paste containing the conductive material.

The external electrode 13 is electrically connected to the connection conductor 25 through the via conductor 31 . The connection conductor 25 is located in the same layer as the internal electrode 19 . The connection conductor 25 is positioned inside the internal electrode 19 . An opening is formed in the internal electrode 19 at a position corresponding to the external electrode 13 when viewed from the Z direction. The connection conductor 25 is positioned within an opening formed in the internal electrode 19 . The entire edge of the connection conductor 25 is surrounded by the internal electrode 19 when viewed from the Z direction.

The connection conductor 25 is positioned between the piezoelectric layers 17a and 17b. The internal electrode 19 and the connection conductor 25 are separated from each other. The connection conductor 25 faces the external electrode 13 in the Z direction. The via conductors 31 are connected to the external electrodes 13 as well as to the connection conductors 25 . The connection conductors 25 are electrically connected to the internal electrodes 21 through via conductors 33 . The connection conductor 25 faces the internal electrode 21 in the Z direction. The via conductors 33 are connected to the connection conductors 25 and the internal electrodes 21 .

Internal electrodes 21 are electrically connected to connection conductors 27 through via conductors 35 . The connection conductor 27 is located in the same layer as the internal electrode 23 . The connection conductor 27 is positioned inside the internal electrode 23 . An opening is formed in the internal electrode 23 at a position corresponding to the external electrode 13 (connection conductor 25) when viewed from the Z direction. The connection conductor 27 is positioned within an opening formed in the internal electrode 23 . The entire edge of the connection conductor 27 is surrounded by the internal electrode 23 when viewed from the Z direction.

The external electrodes 15 are electrically connected to the internal electrodes 19 through via conductors 37 . The internal electrode 19 faces the external electrode 15 in the Z direction. The via conductors 37 are connected to the external electrodes 15 as well as to the internal electrodes 19 .

The internal electrode 19 is electrically connected to the connection conductor 29 through the via conductor 39 . The connection conductor 29 is located in the same layer as the internal electrode 21 . The connection conductor 29 is positioned inside the internal electrode 21 . An opening is formed in the internal electrode 21 at a position corresponding to the external electrode 15 when viewed from the Z direction. The connection conductor 29 is positioned within an opening formed in the internal electrode 21 . The entire edge of the connection conductor 29 is surrounded by the internal electrode 21 when viewed in the Z direction.

The connection conductor 29 is located between the piezoelectric layer 17b and the piezoelectric layer 17c. The internal electrode 21 and the connection conductor 29 are separated from each other. The connection conductor 29 faces the internal electrode 19 in the Z direction. The via conductors 39 are connected to the internal electrodes 19 as well as to the connection conductors 29 . The connection conductors 29 are electrically connected to the internal electrodes 23 through via conductors 41 . The connection conductor 29 faces the internal electrode 23 in the Z direction. The via conductors 41 are connected to the connection conductors 29 and the internal electrodes 23 .

The external electrodes 13 are electrically connected to the internal electrodes 21 through via conductors 31 , connection conductors 25 , and via conductors 33 . The external electrodes 15 are electrically connected to the internal electrodes 19 through via conductors 37 . The external electrodes 15 are electrically connected to the internal electrodes 23 through via conductors 37 , internal electrodes 19 , via conductors 39 , connection conductors 29 , and via conductors 41 .

The connection conductors 25, 27, 29 and via conductors 31, 33, 35, 37, 39, 41 are made of a conductive material. Each of via conductors 31, 33, 35, 37, 39, and 41 is a via conductor group consisting of a plurality of via conductors, but may be a single via conductor. The via conductors 31 and 33 arranged in the piezoelectric layers 17a and 17b adjacent to each other in the Z direction are spaced apart from each other when viewed in the Z direction and are arranged so as not to overlap each other. The via conductors 37 and 39 arranged in the piezoelectric layers 17a and 17b are spaced apart from each other when viewed in the Z direction and are arranged so as not to overlap each other. The via conductors 33 and 35 arranged in the piezoelectric layers 17b and 17c adjacent to each other in the Z direction are spaced apart from each other when viewed in the Z direction and are arranged so as not to overlap each other. The via conductors 39 and 41 arranged in the piezoelectric layers 17b and 17c are spaced apart from each other when viewed in the Z direction and are arranged so as not to overlap each other.

Ag, Pd, or Ag--Pd alloy is used for the conductive material, for example. The connection conductors 25, 27, 29 and the via conductors 31, 33, 35, 37, 39, 41 are formed, for example, as sintered bodies of conductive paste containing the conductive material. The connection conductors 25, 27, 29 are rectangular. The via conductors 31, 33, 35, 37, 39, 41 are formed by sintering the conductive paste filled in the through holes formed in the ceramic green sheets for forming the corresponding piezoelectric layers 17a, 17b, 17c. It is formed by

A conductor electrically connected to the internal electrodes 19 and 23 and a conductor electrically connected to the internal electrode 21 are not arranged on the main surface 11 b of the piezoelectric element 11 . In this embodiment, the main surface 11b is entirely exposed when viewed from the Z direction. The main surfaces 11a and 11b are natural surfaces. A natural surface is a surface formed by the surfaces of crystal grains grown by firing.

Neither the conductors electrically connected to the internal electrodes 19 and 23 nor the conductors electrically connected to the internal electrode 21 are disposed on the side surfaces 11e of the piezoelectric element 11 either. In this embodiment, when each side surface 11e of the piezoelectric element 11 is viewed from the X direction and the Y direction, each side surface 11e is entirely Exposed. In this embodiment, each of these side surfaces 11e is also a natural surface.

A region sandwiched between the internal electrode 19 and the internal electrode 21 in the piezoelectric layer 17b and a region sandwiched between the internal electrode 21 and the internal electrode 23 in the piezoelectric layer 17c constitute a piezoelectrically active region. . In this embodiment, the piezoelectrically active regions are located so as to surround the plurality of external electrodes 13 and 15 when viewed in the Z direction. Viewed in the Z-direction, the piezoelectric body 11 includes a piezoelectrically active region in the region located between the outer electrodes 13 and 15 . Viewed in the Z-direction, the piezoelectric body 11 also includes piezoelectrically active regions outside the regions in which the external electrodes 13 and 15 are located.

As shown in FIGS. 1 to 4, the connection structure 2 has a strip-shaped wiring member 50 connected to the vibrating portion 1 and a plurality of lead wires 80 connected to the wiring member 50. . In this embodiment, the connection structure 2 has two lead wires 80 .

FIG. 6 is a top view of the connection structure and the piezoelectric element. As shown in FIGS. 1 to 6, the wiring member 50 extends along the long side 11c of the main surface 11a when viewed from the facing direction (Z direction) of the main surfaces 11a and 11b. intersects with the short side 11d of . In this embodiment, the wiring member 50 is arranged so as to be orthogonal to the short side 11d of the main surface 11a. The direction in which the wiring member 50 extends is orthogonal to the Y direction. The wiring member 50 extends in the X direction. The wiring member 50 has one end electrically and physically connected to the piezoelectric element 10 and the other end electrically and physically connected to the lead wire 80 .

The vibration device 100 includes a joint member 70 , a joint member 71 , and a joint member 72 . The wiring member 50 is joined (bonded) to the vibrating portion 1 by a joining member 70 and a joining member 71 . The wiring member 50 is joined (bonded) to the case 3 by a joining member 72 . The joint member 70, the joint member 71, and the joint member 72 are arranged apart from each other.

The joining member 70 is a resin layer containing a plurality of conductive particles (not shown) and has electrical conductivity. Conductive particles are, for example, metal particles and gold-plated particles. The joining member 70 contains thermosetting elastomer, for example. The joining member 70 is formed, for example, by curing an anisotropic conductive paste or an anisotropic conductive film. The joint member 71 does not contain conductive particles and has electrical insulation. The joining member 71 contains nitrile rubber, for example. The joint member 71 may contain the same resin material as the resin material contained in the joint member 70 . The joining member 72 does not contain conductive particles and has electrical insulation. The joining member 72 is made of, for example, epoxy resin or acrylic resin.

The wiring member 50 has a first region R1, a second region R2, a third region R3, a fourth region R4, and a fifth region R5.

The first region R1 faces the main surface 11a in the Z direction. The first region R1 is located on the plurality of external electrodes 13,15. The first region R1 integrally covers the plurality of external electrodes 13 and 15. As shown in FIG. The plurality of external electrodes 13 and 15 are not exposed from the first region R1 when viewed from the Z direction. The first region R1 is joined to the plurality of external electrodes 13 and 15 and the main surface 11a by the joining member 70. As shown in FIG. The joining member 70 is provided between the first region R1 and the piezoelectric element 10 so as to integrally cover the plurality of external electrodes 13 and 15 when viewed from the Z direction. The first region R1 is supported by the piezoelectric element 10. As shown in FIG.

In this embodiment, the first region R1 has a rectangular shape when viewed from the Z direction. The long side direction of the first region R1 is the X direction and coincides with the long side direction of the main surface 11a. When viewed from the Z direction, the short side direction of the first region R1 is the Y direction and coincides with the short side direction of the main surface 11a. The length of the first region R1 in the Y direction is shorter than the length of the wiring member 50 in the Y direction.

The second region R2 faces the main surface 11a in the Z direction. The second region R2 is separated from the first region R1 in the X direction. The second region R2 is joined to the main surface 11a by a joining member 71. As shown in FIG. The joining member 71 joins the entire width direction (Y direction) of the wiring member 50 to the main surface 11a. The second region R2 is joined to one end 11f in the long side direction of the main surface 11a. The second region R2 is supported by the piezoelectric element 10. As shown in FIG.

The length of the second region R2 in the Y direction is equivalent to the width of the wiring member 50 (the length of the wiring member 50 in the Y direction). The joining member 71 is provided along one short side 11d of the main surface 11a. The joining member 71 has a main surface portion provided on the main surface 11a (specifically, the end portion 11f) and a side surface portion 71a provided on the side surface 11e. The side portion 71a is provided at the end of the side surface 11e on the main surface 11a side.

The distance between the second region R2 and the main surface 11a in the Z direction gradually increases as the second region R2 is separated from the third region R3. The maximum distance between the principal surface 11a and the second region R2 in the Z direction is greater than the maximum distance between the principal surface 11a and the first region R1 in the Z direction.

The third region R3 is located between the first region R1 and the second region R2 and connects the first region R1 and the second region R2 to each other. The third region R3 is adjacent to each of the first region R1 and the second region R2. The third region R3 is separated from the main surface 11a. The third region R3 is not joined to the piezoelectric element 10. As shown in FIG. The Y-direction length of the third region R3 matches the Y-direction length of the first region R1.

The first region R1, the second region R2, and the third region R3 overlap the main surface 11a when viewed from the Z direction. A region of the wiring member 50 that overlaps with the main surface 11a when viewed in the Z direction includes a first region R1, a second region R2, and a third region R3.

The fourth region R4 is supported by the support portion 3f. The fourth region R4 overlaps the support portion 3f when viewed from the Z direction. The fourth region R4 is joined (bonded) to the support portion 3f by a joining member 72. As shown in FIG. The fourth region R4 is fixed to the support portion 3f. The joint member 72 is provided on the surface of the cover 57 in the fourth region R4.

The fifth region R5 is located between the second region R2 and the fourth region R4 and connects the second region R2 and the fourth region R4 to each other. The fifth region R5 is adjacent to each of the second region R2 and the fourth region R4. The fifth region R5 does not overlap the supporting portion 3f and the main surface 11a when viewed from the Z direction. The fifth region R5 is curved.

The distance L1 between the first region R1 and the second region R2 in the X direction is shorter than the distance L2 between the second region R2 and the fourth region R4 in the X direction. The interval L1 is equivalent to the length of the third region R3 in the X direction. The interval L2 is equivalent to the length of the fifth region R5 in the X direction.

FIG. 6 is a top view of the connection structure and the piezoelectric element. FIG. 7 is a bottom view of the connecting structure. As shown in FIGS. 1 to 7, the wiring member 50 has a base 51, a plurality of conductor layers 53, 55, a cover 57, and a reinforcing member 59. As shown in FIG. In this embodiment, the wiring member 50 has two conductor layers 53 and 55 . The wiring member 50 is, for example, a flexible printed circuit board (FPC) or a flexible flat cable (FFC).

The base 51 has a strip shape and has a pair of main surfaces 51a and 51b facing each other. The base 51 has electrical insulation. The base 51 is, for example, a resin layer made of resin such as polyimide resin. The thickness of base 51 is, for example, 100 μm.

Each conductor layer 53 , 55 is arranged on the major surface 51 a of the base 51 . Each conductor layer 53, 55 is joined (adhered) to the main surface 51a by an adhesive layer (not shown). Each conductor layer 53, 55 is made of Cu, for example. Each of the conductor layers 53 and 55 may have, for example, a structure in which a Ni plated layer and an Au plated layer are provided in this order on a Cu layer. The conductor layer 53 and the conductor layer 55 are arranged apart from each other. The thickness of each conductor layer 53, 55 is, for example, 20 μm.

The conductor layer 53 includes an end portion 53a connected to the lead wire 80, an end portion 53b connected to the external electrode 13, and a connection portion 53c connecting the end portions 53a and 53b. there is The connecting portion 53c extends in the direction in which the wiring member 50 extends (X direction). The end portion 53a is adjacent to one end portion of the connection portion 53c in the direction in which the wiring member 50 extends. The end portion 53 b is adjacent to the other end portion of the connection portion 53 c in the width direction (Y direction) of the wiring member 50 .

The conductor layer 55 includes an end portion 55a connected to the lead wire 80, an end portion 55b connected to the external electrode 15, and a connection portion 55c connecting the end portions 55a and 55b. there is The connecting portion 55c extends in the direction in which the wiring member 50 extends (X direction). The end portion 55a is adjacent to one end portion of the connection portion 55c in the direction in which the wiring member 50 extends. The end portion 55 b is adjacent to the other end portion of the connection portion 55 c in the width direction (Y direction) of the wiring member 50 .

The end portion 53 a and the end portion 55 a are arranged apart from each other in the width direction of the wiring member 50 . The end portion 53b and the end portion 55b are arranged apart from each other in the direction in which the wiring member 50 extends. The connecting portion 53 c and the connecting portion 55 c are arranged parallel to each other and spaced apart from each other in the width direction of the wiring member 50 .

A joint member 70 is present between the end portion 53 a and the external electrode 13 . The end portion 53 a and the external electrode 13 are electrically connected through conductive particles contained in the joint member 70 . A joint member 70 is present between the end portion 55 a and the external electrode 15 . The end portion 55 a and the external electrode 15 are electrically connected through conductive particles contained in the joint member 70 .

The cover 57 is arranged on the main surface 51a, as particularly shown in FIG. The cover 57 covers the conductor layers 53, 55 and the main surface 51a. The cover 57 is joined (adhered) to the conductor layers 53 and 55 and to the regions exposed from the conductor layers 53 and 55 on the main surface 51a by adhesive layers (not shown). The cover 57 is, for example, a resin layer made of resin such as polyimide resin. The thickness of cover 57 is, for example, 25 μm.

Edges 53 a and 53 b of the conductor layer 53 , edges 55 a and 55 b of the conductor layer 55 , and a partial region of the main surface 51 a are exposed from the cover 57 . The partial regions of the main surface 51a are a region arranged between the ends 53a and 55a and a region arranged between the ends 53b and 55b when viewed from the Z direction. . Each end 53a, 53b, 55a, 55b is plated with, for example, nickel plating and gold flash plating.

The reinforcing member 59 is arranged at the other end of the wiring member 50 . The reinforcing member 59 is arranged on the principal surface 51 b of the base 51 . The reinforcing member 59 is joined (adhered) to the main surface 51b by an adhesive layer (not shown). The reinforcing member 59 is a rectangular plate-shaped member having electrical insulation. Reinforcing member 59 is made of, for example, polyimide resin.

The lead wire 80 has a bundle 81 of a plurality of core wires and a covering member 82 covering the bundle 81 . In this embodiment, the lead wire 80 has 12 core wires. A covering member 82 covers the outer circumference of the bundle 81 . The covering member 82 collectively covers the plurality of core wires. The ends of the bundle 81 are exposed from the covering member 82 and connected to the ends 53a and 55a of the conductor layers 53 and 55, respectively. The ends of bundle 81 are connected to respective ends 53a, 55a by conductive adhesive. A conductive adhesive is, for example, a hot-melt metal such as solder. The conductive adhesive may be formed using a conductive paste containing Au, Cu, or the like as a conductive material.

An electronic device having the vibrating device 100 generates sound by vibrating the piezoelectric element 10 . Vibration of the piezoelectric element 10 may produce not only sound but also tactile sensation.

As described above, the wiring member 50 has the second region R2 joined to the main surface 11a of the piezoelectric body 11 in addition to the first region R1 joined to the external electrodes 13 and 15. . Therefore, even when the vibrating device 100 vibrates, a mechanical load is less likely to act on the joints between the first region R1 and the external electrodes 13 and 15 . Therefore, separation between the first region R1 and the external electrodes 13 and 15 is less likely to occur.

Further, the wiring member 50 has a third region R3 located between the first region R1 and the second region R2 and separated from the main surface 11a of the piezoelectric body 11. As shown in FIG. Therefore, even when the first region R1 and the external electrodes 13 and 15 are joined with the conductive joining member 70, and the second region R2 and the main surface 11a of the piezoelectric element 11 are joined with the insulating joining member 71, , and the third region R3, a gap is secured between the joint member 70 and the joint member 71. As shown in FIG. That is, the joint member 70 and the joint member 71 can be maintained in a state of being separated from each other. This prevents the joining member 71 from pushing away the joining member 70 and entering between the first region R1 and the external electrodes 13 and 15, thereby preventing the wiring member 50 and the external electrodes 13 and 15 from becoming poorly connected. be.

As described above, in the vibrating device 100, the electrical connection between the external electrodes 13 and 15 and the wiring member 50 is ensured. Therefore, the electrical reliability of the vibrating device 100 is less likely to deteriorate.

The main surface 11a has a rectangular shape. Therefore, the amount of displacement of the piezoelectric element 11 is the largest at the center of the main surface 11a in the long side direction (X direction) and the smallest at both ends of the main surface 11a in the long side direction, that is, the short side 11d. When viewed from the Z direction, the wiring member 50 extends along the long side 11c of the main surface 11a and intersects the short side 11d of the main surface 11a. The second region R2 is joined to one end 11f in the long side direction of the main surface 11a. Therefore, the amount of displacement of the second region R2 is smaller than when the second region R2 is joined to the end of the main surface 11a in the short side direction (Y direction), that is, to the long side 11c.

Since the second region R2 is supported by the piezoelectric element 10, it is displaced as the piezoelectric element 10 is displaced. In the wiring member 50, since the fifth region R5 is connected to the second region R2, it tends to displace along with the displacement of the second region R2. However, the fifth region R5 is also connected to the fourth region R4. Since the fourth region R4 is supported by the support portion 3f, it does not displace. Therefore, the vibration of the fifth region R5 does not match the vibration of the piezoelectric element 10, and there is a possibility that the vibration of the piezoelectric element 10 is inhibited. In the vibrating device 100, the amount of displacement of the second region R2 is relatively small, so the displacement of the fifth region R5 connected to the second region R2 is suppressed. Therefore, the vibration of the piezoelectric element 10 is less likely to be disturbed, and the amplitude of the piezoelectric element 10 can be increased.

The distance L1 between the first region R1 and the second region R2 in the X direction is shorter than the distance L2 between the second region R2 and the fourth region R4 in the X direction. In this case, the third region R3 is easily deformed following the vibration of the piezoelectric element 10, and the distortion of the wiring member 50 can be concentrated on the play of the fifth region R5. Thus, the fifth region R5 tends to function effectively, so the amplitude of the piezoelectric element 10 can be increased.

A bottom portion 3a of the case 3 holds both end portions 1a of the vibrating portion 1 in the X direction. Therefore, it is possible to further increase the amplitude at the central portion of the vibrating portion 1 in the X direction.

The distance between the second region R2 and the main surface 11a in the Z direction gradually increases as the second region R2 is separated from the third region R3. Therefore, compared to the case where the distance between the second region R2 and the main surface 11a is the same as the distance between the third region R3 and the main surface 11a, the distance between the second region R2 and the main surface 11a The volume of the joint member 71 provided can be increased. Thereby, in the wiring member 50, the vibration of the fifth region R5 is easily absorbed. Therefore, the vibration of the piezoelectric element 10 is hardly disturbed, and the amplitude of the piezoelectric element 10 can be further increased. For example, it is conceivable to provide a stepped portion in the third region R3 and increase the distance between the second region R2 and the main surface 11a, but in this case, the mechanical load tends to concentrate on the stepped portion. On the other hand, in the vibrating device 100, the second region R2 is gradually separated from the main surface 11a, so there is no need to provide the wiring member 50 with a stepped portion.

The joining member 71 has a side portion 71a provided on the side surface 11e. Since the bonding member 71 is provided not only on the main surface 11a but also on the side surface 11e, the bonding strength between the second region R2 and the piezoelectric body 11 is improved. As a result, even when the vibration device 100 vibrates, a mechanical load is less likely to act on the joints between the first region R1 and the external electrodes 13 and 15 . Therefore, separation between the first region R1 and the external electrodes 13 and 15 is even less likely to occur. Moreover, since the joint member 71 is insulative, the occurrence of a short circuit is suppressed.

The maximum distance between the main surface 11a and the second region R2 in the Z direction is larger than the maximum distance between the main surface 11a and the first region R1 in the X direction. As a result, the wiring member 50 can be easily deformed smoothly, and the amplitude of the piezoelectric element 10 can be increased more effectively.

The vibrating portion 1 has a vibrating member 12 to which a piezoelectric element 10 is joined. Therefore, vibration of the piezoelectric element 10 can be increased.

The external electrodes 13 and 15 are arranged in the central portion of the main surface 11a. Therefore, the piezoelectric element 10 can be vibrated in a well-balanced manner.

Since the electronic device according to the present embodiment includes the vibrating device 100, electrical reliability is less likely to deteriorate.

The present invention is not necessarily limited to the above-described embodiments, and various modifications are possible without departing from the scope of the invention.

FIG. 8 is a partially enlarged cross-sectional view of a vibration device according to a modification. As shown in FIG. 8, in a vibrating device 100A according to the modified example, the recess 3d is not provided in the case 3, and the entire main surface 12b of the vibrating member 12 is bonded (bonded) to the bottom portion 3a by the adhesive layer 60. It is different from the vibration device 100 in that Even in this case, electrical connection between the external electrodes 13 and 15 and the wiring member 50 is ensured. Therefore, the electrical reliability of the vibrating device 100A is less likely to deteriorate.

In the vibrating devices 100 and 100A, the vibrating section 1 includes the vibrating member 12, but the vibrating section 1 does not have to include the vibrating member 12. FIG. In this case, the structure of the vibrating portion 1 can be simplified.

DESCRIPTION OF SYMBOLS 1... Vibration part 1a... End part 3a... Bottom part (holding part) 10... Piezoelectric element 11... Piezoelectric body 11a... Main surface (first main surface) 11b... Main surface (second main surface) , 11c long side 11d short side 11e side surface 11f end 12 vibration member 13, 15 external electrode 19, 21, 23 internal electrode 50 wiring member 71 joining member , 71a... side portion, 100, 100A... vibration device, R1... first area, R2... second area, R3... third area, R4... fourth area, R5... fifth area.

Claims (10)

a vibrating portion having a piezoelectric element;
a wiring member electrically connected to the piezoelectric element;
a conductive joining member;
and an insulating joining member ,
The piezoelectric element has a piezoelectric body, an internal electrode arranged inside the piezoelectric body, and an external electrode electrically connected to the internal electrode,
The piezoelectric body has a first main surface and a second main surface facing each other, and the first main surface and the second main surface are adjacent to each other, and the first main surface and the second main surface are adjacent to each other. and side surfaces extending in opposite directions of
The external electrode is arranged on the first main surface,
The wiring member is
a first region located on the external electrode and joined to the external electrode;
a second region joined to the first main surface;
a third region positioned between the first region and the second region and spaced apart from the first major surface ;
The conductive joint member joins the external electrode and the first region,
The vibration device, wherein the insulating joining member is arranged between the first main surface and the second region in the facing direction, and joins the first main surface and the second region. 2. The vibration device according to claim 1 , wherein said insulating joining member has a side portion provided on said side. a vibrating portion having a piezoelectric element;
a wiring member electrically connected to the piezoelectric element,
The piezoelectric element has a piezoelectric body, an internal electrode arranged inside the piezoelectric body, and an external electrode electrically connected to the internal electrode,
The piezoelectric body has a first main surface and a second main surface facing each other, and the first main surface and the second main surface are adjacent to each other, and the first main surface and the second main surface are adjacent to each other. and side surfaces extending in opposite directions of
The external electrode is arranged on the first main surface,
The wiring member is
a first region located on the external electrode and joined to the external electrode;
a second region joined to the first main surface;
a third region positioned between the first region and the second region and spaced apart from the first major surface ;
The vibrating device , wherein the distance between the second region and the first main surface in the facing direction gradually increases as the second region separates from the third region. The first main surface has a rectangular shape,
When viewed from the facing direction, the wiring member extends along the long side of the first main surface and intersects the short side of the first main surface,
The vibration device according to any one of claims 1 to 3 , wherein the second region is joined to one end of the first main surface in the long side direction. The wiring member further has a fourth region supported by a support portion and a fifth region located between the second region and the fourth region,
5. The vibration device according to claim 4 , wherein the distance between said first area and said second area in said long side direction is shorter than the distance between said second area and said fourth area in said long side direction. 6. The vibrating device according to claim 4 , further comprising a holding portion holding both ends of said vibrating portion in the long side direction of said first main surface. Claims 1 to 6, wherein the maximum value of the distance between said first principal surface and said second region in said facing direction is larger than the maximum value of distance between said first principal surface and said first region in said facing direction. The vibrating device according to any one of Claims 1 to 3. The vibrating device according to any one of claims 1 to 7, wherein the vibrating portion further includes a vibrating member to which the piezoelectric element is bonded. The vibration device according to any one of claims 1 to 8, wherein the external electrode is arranged in the central portion of the first main surface. An electronic device comprising the vibration device according to any one of claims 1 to 9.

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