JP7259278B2 - Vibration device and electronic equipment - Google Patents

Description

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

Patent Literature 1 describes an acoustic generator including a piezoelectric element and a wiring member electrically connected to the piezoelectric element. In this acoustic generator, the wiring member has a bent portion or curved portion. As a result, the vibration of the wiring member is absorbed by the curved portion or the bent portion, so that the vibration of the wiring member can be suppressed.

Japanese Patent No. 6016945

One aspect of the present invention provides a vibrating device and electronics capable of increasing amplitude.

A vibration device according to one aspect of the present invention includes a piezoelectric element having a rectangular main surface, internal electrodes arranged inside the piezoelectric element, arranged on the main surface, and a vibrating portion having a piezoelectric element including an external electrode electrically connected to the internal electrode; extends along the long side of the main surface and intersects the short side of the main surface, and the wiring member has a first region supported by the vibrating portion and a second region supported by the supporting portion and a third region connected to the first region and the second region, the third region including a bend.

In the above aspect, since the main surface has a rectangular shape, the amount of displacement of the piezoelectric element is the largest at the center in the long side direction of the main surface and the largest at both ends in the long side direction of the main surface. become smaller. The wiring member has a first area supported by the vibration part, a second area supported by the support part, and a third area connected to the first area and the second area. there is Since the first region is supported by the vibrating portion, it is displaced with the displacement of the vibrating portion. Since the third area is connected to the first area, it tries to displace along with the displacement of the first area. The third area is also connected to the second area. The second region is supported by the support and does not move. Therefore, the vibration of the third region does not match the vibration of the piezoelectric element, and may impede the vibration of the piezoelectric element.

The wiring member extends along the long side of the main surface of the piezoelectric element and crosses the short side of the main surface of the piezoelectric element. Therefore, the third region is connected to the first region at the short side portion of the main surface of the piezoelectric body. As described above, the amount of displacement of the main surface is the smallest at both ends in the long side direction of the main surface. Therefore, when the wiring member extends along the short side of the main surface of the piezoelectric element and intersects the long side of the main surface of the piezoelectric element, that is, the third region is the main surface of the piezoelectric element. Vibration of the third region is suppressed compared to the case where the long side of is connected to the first region. As a result, the vibration of the piezoelectric element is less likely to be disturbed, and the amplitude of the piezoelectric element can be increased. Since the third area is curved, there is play in the third area. Therefore, transmission of external vibration to the piezoelectric element through the wiring member is suppressed. As a result, the vibration of the piezoelectric element is less likely to be disturbed, and the amplitude of the piezoelectric element can be further increased.

In the above aspect, the length of the third region in the orthogonal direction may be longer than the length of the piezoelectric element in the orthogonal direction. In this case, the play in the third area tends to increase. Therefore, the amplitude of the piezoelectric element is further increased.

In the one aspect described above, the radius of curvature of the curved portion may be greater than the amplitude of the piezoelectric element. In this case, the influence of reverberation can be suppressed.

The one aspect may further include holding portions that hold both end portions of the vibrating portion in the long-side direction of the 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 vibrating section may further include a vibrating member to which the piezoelectric element is joined. In this case, in this case, the vibration of the piezoelectric element can be increased.

In the one aspect described above, the external electrode may be arranged in the central portion of the 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 vibration device is provided, the vibration of the piezoelectric element is less likely to be hindered.

According to one aspect of the present invention, it is possible to provide a vibrating device and electronic equipment in which vibration of a piezoelectric element is less likely to be disturbed.

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. A rectangular shape also includes a square shape. 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 facing each other in the Z direction. 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, each internal electrode 19, 21, 23 is not exposed on each side surface. 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 each side surface of the piezoelectric element 11 . In this embodiment, when each side surface of the piezoelectric body 11 is viewed from the X direction and the Y direction, the entire side surface is exposed. In this embodiment, each of these sides is also a natural side.

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 principal surface 11a when viewed from the orthogonal direction (Z direction) perpendicular to the principal surface 11a. 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 wiring member 50 is positioned above the plurality of external electrodes 13 and 15 . The wiring member 50 is electrically connected to the plurality of external electrodes 13 and 15 by the joint members 70 . The joining member 70 is provided between one end of the wiring member 50 and the piezoelectric element 10 so as to integrally cover the plurality of external electrodes 13 and 15 when viewed in the Z direction. The joining member 70 is a resin layer containing a plurality of conductive particles (not shown). 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 wiring member 50 is also joined to the main surface 11 a by a joining member 71 . The wiring member 50 is joined to the main surface 11 a by a joining member 71 . The joining member 71 does not contain a conductive filler and has electrical insulation. The joining member 71 is arranged along one short side 11d of the main surface 11a. The joining member 71 joins the entire width direction (Y direction) of the wiring member 50 to the main surface 11a. The joint member 71 is separated from the joint member 70 . 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 wiring member 50 has a first region R1, a second region R2, and a third region R3 that are continuous and integrated.

The first region R1 is supported by the vibrating section 1. As shown in FIG. The first region R1 is arranged on the main surface 11a. The first region R1 is joined (bonded) to the main surface 11a by a joining member 70 and a joining member 71, which will be described later. The first region R1 is fixed to the main surface 11a. Thereby, the first region R1 is displaced integrally with the main surface 11a. One end of the first region R1 in the X direction is bonded to one end of the main surface 11a in the X direction and the joining member 71 . The first region R1 overlaps the main surface 11a when viewed from the Z direction.

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. 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 first region R1 extends along the long side 11c of the main surface 11a and reaches one short side 11d of the main surface 11a. The first region R1 is joined to the piezoelectric element 10 by a joining member 70 so as to integrally cover the plurality of external electrodes 13 and 15. As shown in FIG. The first region R1 entirely covers the plurality of external electrodes 13 and 15 . The plurality of external electrodes 13 and 15 are not exposed from the first region R1 when viewed from the Z direction.

The second region R2 is supported by the support portion 3f. The second region R2 overlaps the support portion 3f when viewed from the Z direction. The second region R2 is joined (bonded) to the support portion 3f by a joining member 72. As shown in FIG. The second region R2 is fixed to the support portion 3f. The joining member 72 is made of, for example, epoxy resin or acrylic resin. The joining member 72 does not contain a conductive filler and has electrical insulation. The joint member 72 is provided on the surface of the cover 57 in the second region R2.

The third region R3 is connected to the first region R1 and the second region R2. The third region R3 is arranged 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 does not overlap the main surface 11a when viewed from the Z direction.

The third region R3 has a first extension portion E1, a second extension portion E2, a third extension portion E3, a first curved portion C1, and a second curved portion C2 that are continuous and integrated with each other. are doing. The first extending portion E1 extends along the X direction and connects the first region R1 and the first curved portion C1 to each other. The first curved portion C1 curves to connect the first extension portion E1 and the second extension portion E2 to each other. The second extending portion E2 extends obliquely upward and connects the first curved portion C1 and the second curved portion C2 to each other. The second curved portion C2 curves to connect the second extension portion E2 and the third extension portion E3 to each other. The third extending portion E3 extends along the X direction and connects the second curved portion C2 and the second region R2 to each other.

Since the wiring member 50 is strip-shaped, the first curved portion C1 and the second curved portion C2 form curved surfaces. The length L1 of the third region R3 in the orthogonal direction (Z direction) to the main surface 11a is longer than the length L2 of the piezoelectric body 11 in the Z direction. The length L1 is, for example, 5 mm or more and 7 mm or less. The length L2 is, for example, 0.2 mm or more and 1.0 mm or less. The curvature radii of the first curved portion C1 and the second curved portion C2 are larger than the amplitude (displacement amount) of the piezoelectric element 10 . The radius of curvature of the first curved portion C1 is, for example, 1 mm or more and 3 mm or less. The radius of curvature of the second curved portion C2 is, for example, 1 mm or more and 3 mm or less. The amplitude of the piezoelectric element 10 is, for example, 20 μm or more and 200 μm or less.

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 configuration 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 piezoelectric element 10 bends and vibrates so that the piezoelectric body 11 is displaced in the Z direction. Since the main surface 11a has a rectangular shape, the amount of displacement of the piezoelectric body 11 is the largest at the center in the long side direction (X direction) of the main surface 11a, and both ends of the main surface 11a in the long side direction. becomes smallest at The wiring member 50 includes a first region R1 supported by the vibrating portion 1, a second region R2 supported by the support portion 3f, and a third region R2 connected to the first region R1 and the second region R2. and a region R3. Since the first region R1 is supported by the vibrating portion 1, it is displaced as the vibrating portion 1 is displaced. Since the third region R3 is connected to the first region R1, it tries to displace along with the displacement of the first region R1. The third region R3 is also connected to the second region R2. The second region R2 is supported by the support portion 3f and is not displaced. Therefore, the vibration of the third region R3 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.

The wiring member 50 extends along the long side 11c of the principal surface 11a of the piezoelectric element 11 and intersects the short side 11d of the principal surface 11a of the piezoelectric element 11 . Therefore, the third region R3 is connected to the first region R1 at the short side portion of the main surface 11a of the piezoelectric body 11. As shown in FIG. As described above, the amount of displacement of the main surface 11a is the smallest at both ends in the long side direction of the main surface 11a. Therefore, when the wiring member 50 extends along the short side 11d of the main surface 11a of the piezoelectric element 11 and intersects the long side 11c of the main surface 11a of the piezoelectric element 11, that is, the third Compared to the case where the region R3 is connected to the first region R1 at the long side portion of the main surface 11a of the piezoelectric body 11, the vibration of the third region R3 is suppressed. As a result, the vibration of the piezoelectric element 10 is less likely to be disturbed, and the amplitude of the piezoelectric element 10 can be increased. Since the third region R3 is curved, there is play in the third region R3. Therefore, transmission of external vibration to the piezoelectric element 10 through the wiring member 50 is suppressed. As a result, the vibration of the piezoelectric element 10 is less likely to be disturbed, and the amplitude of the piezoelectric element 10 can be further increased.

The play in the third region R3 makes it difficult for the vibration of the piezoelectric element 10 to be disturbed, and in this respect the amplitude of the piezoelectric element 10 can be further increased. Also, the load applied to the joint member 71 due to external vibration and vibration of the piezoelectric element 10 can be suppressed. Therefore, it is possible to prevent the wiring member 50 from peeling off from the main surface 11a.

The length L1 of the third region R3 in the Z direction is longer than the length L2 of the piezoelectric body 11 in the Z direction. The play of the third region R3 tends to increase as the length L1 is longer than the length L2. Therefore, in this embodiment, the amplitude of the piezoelectric element 11 is further increased. Moreover, peeling of the wiring member 50 can be further suppressed. The longer the length L1, the smaller the influence on the generated force (vibration) of the vibrating device 100 becomes.

Since the third region R3 has the first curved portion C1 and the second curved portion C2, there is play in the third region R3. Since the play absorbs external vibration, the vibration of the piezoelectric element 10 is less likely to be disturbed. When the radii of curvature of the first curved portion C1 and the second curved portion C2 are smaller than the amplitude of the piezoelectric element 10, the lengths of the linear extending portions E1, E2, and E3 of the wiring member 50 are increased. Virtual walls are created in places other than case 3, and room resonance with large variations is likely to occur. Therefore, the influence of each of the extensions E1, E2, and E3 in which reverberation (eigenfrequency) is generated due to room resonance derived from the wiring member 50 is increased. In contrast, in the present embodiment, the radii of curvature of the first curved portion C1 and the second curved portion C2 are larger than the amplitude of the piezoelectric element 10 . Therefore, the influence of reverberation can be suppressed. The radius of curvature of the first curved portion C1 and the second curved portion C2 may be longer than the length of each extension E1, E2, E3.

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 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 this embodiment includes the vibration device 100, the amplitude of the piezoelectric element 10 can be increased.

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, the vibration of the piezoelectric element 10 is less likely to be disturbed.

In the vibrating devices 100 and 100A, the third region R3 of the wiring member 50 does not have to have the first extending portion E1. In this case, the first curved portion C1 and the first region R1 are directly connected. The third region R3 may not have the second extension E2. In this case, the first curved portion C1 and the second curved portion C2 are directly connected. The third region R3 may not have the third extension E3. In this case, the second curved portion and the third region R3 are directly connected. It is sufficient that the third region R3 has at least the first curved portion C1. The play generated by the first curved portion C1 absorbs external vibrations.

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 section 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 11c... Long side 11d... Short side 12... Vibration member 13 , 15... External electrode, 19, 21, 23... Internal electrode, 50... Wiring member, 100, 100A... Vibration device, C1... First curved portion, C2... Second curved portion, R1... First region, R2... Second Two regions, R3... third region.

Claims (7)

a piezoelectric element having a rectangular main surface; an internal electrode arranged inside the piezoelectric element; a vibrating portion having a piezoelectric element including an external electrode,
and a wiring member connected to the external electrode,
When viewed in an orthogonal direction orthogonal to the main surface, the wiring member extends along the long side of the main surface and intersects the short side of the main surface,
The wiring member includes a first region supported by the vibrating portion by being joined to the vibrating portion by a conductive first joining member and an electrically insulating second joining member; a supported second region; and a third region connected to a portion of the first region that is joined to the second joining member and the second region;
The third region includes a curved portion,
The wiring member includes a base having a first main surface and a second main surface facing each other, and a conductive layer disposed on the first main surface,
The vibrating device, wherein in the first region, the second main surface is provided facing the space. 2. The vibration device according to claim 1, wherein the length of the third region in the orthogonal direction is longer than the length of the piezoelectric body in the orthogonal direction. 3. The vibration device according to claim 2, wherein the radius of curvature of said curved portion is greater than the amplitude of said piezoelectric element. The vibrating device according to any one of claims 1 to 3, further comprising holding portions that hold both ends of the vibrating portion in the long side direction of the main surface. The vibrating device according to any one of claims 1 to 4, 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 5, wherein the two external electrodes are arranged in the central portion of the main surface. An electronic device comprising the vibration device according to any one of claims 1 to 6.

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