JP2020088007A - Vibration device and electronic apparatus - Google Patents

Abstract

To provide a vibration device and electronic apparatus in which vibration of piezoelectric element is hard to be blocked.SOLUTION: A vibration device 100 includes a vibration part 1, and a wiring member 50. The vibration part 1 has a piezoelectric element 10. The piezoelectric element 10 includes a piezoelectric body 11 having a rectangular principal surface 11a, and external electrodes 13, 15 placed on the principal surface 11a, and electrically connected with an internal electrode. When viewing from a direction orthogonal to the principal surface 11a, the wiring member 50 extends along the long side 11d of the principal surface 11a, and intersecting the short side 11d of the principal surface 11a. The wiring member 50 has a first region R1 supported by the vibration part 1, a second region R2 supported by a support part 3f, and a third region R3 connected with the first and second regions R1, R2. The third region R3 includes first and second bends C1, C2.SELECTED DRAWING: Figure 1

Description

One embodiment of the present invention relates to a vibrating device and electronic equipment.

Patent Document 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 a curved portion. Accordingly, 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 electronic equipment capable of increasing amplitude.

A vibrating device according to one aspect of the present invention, a piezoelectric element having a rectangular main surface, an internal electrode arranged inside the piezoelectric element, and arranged on the main surface, and The wiring member includes a vibrating portion having a piezoelectric element including an external electrode electrically connected to the internal electrode, and a wiring member connected to the external electrode, as viewed from an orthogonal direction orthogonal to the main surface. Extends along the long side of the main surface and intersects with 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 the curved portion.

In the one aspect described above, since the main surface has a rectangular shape, the displacement amount of the piezoelectric element is the largest at the center of the main surface in the long side direction, and is the largest at both ends of the main surface in the long side direction. Get smaller. The wiring member has a first region supported by the vibrating portion, a second region supported by the supporting portion, and a third region connected to the first region and the second region. There is. Since the first region is supported by the vibrating section, it is displaced along with the displacement of the vibrating section. Since the third area is connected to the first area, it tends to be displaced 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 supporting portion and is not displaced. Therefore, the vibration of the third region does not match the vibration of the piezoelectric element, which may hinder the vibration of the piezoelectric element.

The wiring member extends along the long side of the main surface of the piezoelectric body and intersects the short side of the main surface of the piezoelectric body. 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 displacement amount of the main surface is 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. The vibration in the third region is suppressed as compared with the case where the long side is connected to the first region. As a result, vibration of the piezoelectric element is less likely to be disturbed, and the amplitude of the piezoelectric element can be increased. Since the third region is curved, there is play in the third region. Therefore, external vibration is suppressed from being transmitted to the piezoelectric element through the wiring member. 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 one aspect, the length of the third region in the orthogonal direction may be longer than the length of the piezoelectric body in the orthogonal direction. In this case, the play in the third region tends to increase. Therefore, the amplitude of the piezoelectric element is further increased.

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

In the above-mentioned one mode, it may further be provided with a holding part holding both ends of the vibrating part in the long side direction of the main surface. In this case, the amplitude at the central portion of the vibrating portion in the long side direction can be further increased.

In the one aspect, 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 above-mentioned one mode, the external electrode may be arranged in the central portion of the main surface. In this case, the piezoelectric element can be vibrated in good balance.

An electronic apparatus according to one aspect of the present invention includes the above vibrating device.

In the above one aspect, since the vibrating device is provided, it is difficult for the vibration of the piezoelectric element to be disturbed.

According to one aspect of the present invention, it is possible to provide a vibrating device and an electronic device in which the vibration of the piezoelectric element is not easily disturbed.

It is a perspective view of a vibrating device according to an embodiment. It is a disassembled perspective view of the vibration device of FIG. FIG. 3 is a sectional view taken along line III-III in FIG. 1. It is sectional drawing which expands and shows a part of FIG. It is an exploded perspective view showing composition of a piezoelectric element. It is a top view of a connection structure and a piezoelectric element. It is a bottom view of a connection structure. It is a partially expanded 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 elements or elements having the same function will be denoted by the same reference symbols, without redundant description.

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

The case 3 is made of a resin material such as an acrylic resin, a vinyl chloride resin, or a molding resin. The case 3 is, for example, a rectangular parallelepiped box member having an open upper surface. 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. The rectangular shape includes, for example, a shape in which each corner is chamfered and a shape in which each corner is rounded. The rectangular shape also includes a square shape. In the following, 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 33 mm, for example. 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 recess 3d is formed in the center of the upper surface of the bottom 3a when viewed from the Z direction. The length of the recess 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) in the Z direction of the recess 3d is 1.0 mm, for example.

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

The case 3 further includes a support portion 3f that supports the connection structure 2. The support portion 3f projects from the end of the one side portion 3c opposite to the bottom portion 3a to the outside of the case 3 along the X direction.

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

The vibrating member 12 is made of, for example, a metal such as Ni—Fe alloy, Ni, brass, or stainless steel. In this embodiment, the vibration member 12 is a plate-shaped 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 such that the outer edge of the vibrating member 12 is located 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 (bonded) to the bottom portion 3a by an adhesive layer 60 made of, for example, an epoxy resin or an acrylic resin. The adhesive layer 60 does not contain a conductive filler and has electrical insulation. The main surface 12b is joined to the peripheral edge of the recess 3d of the bottom 3a and is supported by the peripheral edge of the recess 3d.

In other words, the bottom portion 3a has both end portions 1a of the vibrating portion 1 in the long side direction (X direction) of the main surface 12a and both end portions 1b of the vibrating portion 1 in the short side direction (Y direction) of the main surface 12a. It functions as a holding unit. In the present 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). The bottom portion 3a may not hold both end portions 1b.

Each main surface 12a, 12b has a rectangular shape having 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 (viewed from the Z direction). In the present embodiment, the long side direction of each main surface 12a, 12b coincides with the X direction. The short side direction of each main surface 12a, 12b corresponds to 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 element body 11 and a plurality of external electrodes 13 and 15. In the present embodiment, the piezoelectric element 10 has two external electrodes 13 and 15. The external electrodes 13 and 15 have different polarities.

The piezoelectric body 11 has a rectangular parallelepiped shape. The rectangular parallelepiped shape includes, for example, a rectangular parallelepiped shape with chamfered corners and ridges, and a rectangular parallelepiped shape with rounded corners and ridges. The piezoelectric element 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 (bonded) to the central portion of the main surface 12a by an adhesive layer 61.

Each main surface 11a, 11b has a rectangular shape. Each main surface 11a, 11b has a rectangular shape having a pair of long sides 11c and a pair of short sides 11d. That is, the piezoelectric element 10 (piezoelectric element body 11) has a rectangular shape having a pair of long sides and a pair of short sides in a plan view (viewed from the Z direction). In the present embodiment, the long side direction of each main surface 11a, 11b coincides with the X direction. The short side direction of each of the main surfaces 11a and 11b coincides with 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 element body 11 is configured by laminating a plurality of piezoelectric body layers 17a, 17b, 17c, 17d. That is, the piezoelectric body 11 has a plurality of stacked piezoelectric layers 17a, 17b, 17c, 17d. In the present 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, 17d are stacked 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 the present embodiment, each piezoelectric layer 17a, 17b, 17c, 17d is made of a piezoelectric ceramic material. Examples of the piezoelectric ceramic material include PZT [Pb(Zr,Ti)O ₃ ], PT(PbTiO ₃ ), PLZT[(Pb,La)(Zr,Ti)O ₃ ], or barium titanate (BaTiO ₃ ). Is used. Each of the piezoelectric layers 17a, 17b, 17c, 17d is made of, for example, a sintered body of a ceramic green sheet containing the above-mentioned piezoelectric ceramic material. In the actual piezoelectric element 11, the piezoelectric layers 17a, 17b, 17c, 17d are integrated so that the boundaries between the piezoelectric layers 17a, 17b, 17c, 17d cannot be recognized.

The piezoelectric element 10 includes a plurality of internal electrodes 19, 21, 23 arranged in the piezoelectric body 11. In the present embodiment, the piezoelectric element 10 includes three internal electrodes 19, 21, 23. Each internal electrode 19, 21, 23 is made of a conductive material. For the conductive material, for example, Ag, Pd, or Ag-Pd alloy is used. Each of the internal electrodes 19, 21 and 23 is formed, for example, as a sintered body of a conductive paste containing the above conductive material. In the present 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 space in the Z direction. The internal electrode 21 and the internal electrode 23 face each other with a space in the Z direction. The internal electrode 19 is located between the piezoelectric layer 17a and the piezoelectric layer 17b. The internal electrode 21 is located between the piezoelectric layer 17b and the piezoelectric layer 17c. The internal electrode 23 is located between the piezoelectric layer 17c and the piezoelectric layer 17d. The internal electrodes 19, 21, 23 are 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. The internal electrodes 19, 21, 23 are separated from all the edges (four sides) of the main surfaces 11a, 11b when viewed from the Z direction.

The plurality of external electrodes 13 and 15 are arranged on the main surface 11a. The external electrode 13 and the external electrode 15 are arranged in the X direction. The external electrode 13 and the external electrode 15 are adjacent to each other in the X direction. The plurality of external electrodes 13 and 15 are arranged at the center of the main surface 11a. The plurality of external electrodes 13 and 15 are separated from all the 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. For the conductive material, for example, Ag, Pd, or Ag-Pd alloy is used. Each of the external electrodes 13 and 15 is formed, for example, as a sintered body of a conductive paste containing the above 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 located 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 located in the opening formed in the internal electrode 19. When viewed from the Z direction, the entire edges of the connection conductor 25 are surrounded by the internal electrode 19.

The connection conductor 25 is located between the piezoelectric layer 17a and the piezoelectric layer 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 conductor 31 is connected to the external electrode 13 and the connection conductor 25. The connection conductor 25 is electrically connected to the internal electrode 21 through the via conductor 33. The connection conductor 25 faces the internal electrode 21 in the Z direction. The via conductor 33 is connected to the connection conductor 25 and the internal electrode 21.

The internal electrode 21 is electrically connected to the connection conductor 27 through the via conductor 35. The connection conductor 27 is located in the same layer as the internal electrode 23. The connection conductor 27 is located 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 located in the opening formed in the internal electrode 23. When viewed from the Z direction, the entire edges of the connection conductor 27 are surrounded by the internal electrode 23.

The external electrode 15 is electrically connected to the internal electrode 19 through the via conductor 37. The internal electrode 19 faces the external electrode 15 in the Z direction. The via conductor 37 is connected to the external electrode 15 and the internal electrode 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 located 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 located in the opening formed in the internal electrode 21. When viewed from the Z direction, the entire edges of the connection conductor 29 are surrounded by the internal electrode 21.

The connection conductor 29 is located between the piezoelectric layers 17b and 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 conductor 39 is connected to the internal electrode 19 and the connection conductor 29. The connection conductor 29 is electrically connected to the internal electrode 23 through the via conductor 41. The connection conductor 29 faces the internal electrode 23 in the Z direction. The via conductor 41 is connected to the connection conductor 29 and also to the internal electrode 23.

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

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

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

Neither conductors electrically connected to the internal electrodes 19 and 23 nor conductors electrically connected to the internal electrodes 21 are arranged on the main surface 11b of the piezoelectric body 11. In the present embodiment, when the main surface 11b is viewed from the Z direction, the entire main surface 11b is exposed. The main surfaces 11a and 11b are natural surfaces. The natural surface is a surface formed by the surface of crystal grains grown by firing.

Neither the conductor electrically connected to the internal electrodes 19 and 23 nor the conductor electrically connected to the internal electrode 21 is arranged on each side surface of the piezoelectric body 11. In the present embodiment, when each side surface of the piezoelectric element body 11 is viewed from the X direction and the Y direction, the entire side surface is exposed. In this embodiment, each of these side surfaces is also a natural surface.

A region of the piezoelectric layer 17b sandwiched by the internal electrodes 19 and 21 and a region of the piezoelectric layer 17c sandwiched by the internal electrodes 21 and 23 constitute a piezoelectrically active region. .. In the present embodiment, the piezoelectrically active region is located so as to surround the plurality of external electrodes 13 and 15 when viewed from the Z direction. When viewed from the Z direction, the piezoelectric element body 11 includes a piezoelectrically active region in a region located between the external electrode 13 and the external electrode 15. When viewed in the Z direction, the piezoelectric body 11 also includes a piezoelectrically active region outside the region where 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 section 1 and a plurality of lead wires 80 connected to the wiring member 50. .. In the present 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 as viewed in the orthogonal direction (Z direction) orthogonal to the main surface 11a, and the main surface 11a Intersects the short side 11d. In the present 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 that is electrically and physically connected to the piezoelectric element 10 and the other end that is electrically and physically connected to the lead wire 80.

The wiring member 50 is located on 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 joining member 70. The joining member 70 is provided between the 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 from the Z direction. The joining member 70 is a resin layer containing a plurality of conductive particles (not shown). The conductive particles are, for example, metal particles and gold plated particles. The joining member 70 contains, for example, a thermosetting elastomer. 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 11a by the joining member 71. The wiring member 50 is joined to the main surface 11a 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 joining member 71 is separated from the joining member 70. The joining member 71 contains, for example, nitrile rubber. The joining member 71 may include the same resin material as the resin material included in the joining member 70.

The wiring member 50 has a first region R1, a second region R2, and a third region R3 that are continuous with each other and are integrated.

The first region R1 is supported by the vibrating section 1. 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 described later. The first region R1 is fixed to the main surface 11a. As a result, 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 the joining member 71 and one end of the main surface 11a in the X direction. The first region R1 overlaps with 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 the joining member 70 so as to integrally cover the plurality of external electrodes 13 and 15. The first region R1 covers the entire 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 in the Z direction.

The second region R2 is supported by the supporting portion 3f. The second region R2 overlaps with the support portion 3f when viewed from the Z direction. The second region R2 is joined (bonded) to the support portion 3f by the joining member 72. The second region R2 is fixed to the support portion 3f. The joining member 72 is made of, for example, an epoxy resin or an acrylic resin. The joining member 72 does not contain a conductive filler and has electrical insulation. The joining 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 with the main surface 11a when viewed from the Z direction.

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

Since the wiring member 50 has a strip shape, the first curved portion C1 and the second curved portion C2 form a curved surface. The length L1 of the third region R3 in the direction orthogonal to the main surface 11a (Z direction) is longer than the length L2 of the piezoelectric element 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 radii of curvature 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 connection structure. As shown in FIGS. 1 to 7, the wiring member 50 includes a base 51, a plurality of conductor layers 53 and 55, a cover 57, and a reinforcing member 59. In this embodiment, the wiring member 50 includes 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 a resin such as a polyimide resin. The base 51 has a thickness of 100 μm, for example.

The conductor layers 53 and 55 are arranged on the main surface 51 a of the base 51. The conductor layers 53 and 55 are joined (bonded) 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 plating layer and an Au plating 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 portion 53a and the end portion 53b. There is. The connection 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 connecting portion 53c in the direction in which the wiring member 50 extends. The end portion 53b is adjacent to the other end portion of the connecting portion 53c in the width direction (Y direction) of the wiring member 50.

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

The end portion 53a and the end portion 55a 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 extending direction of the wiring member 50. The connection portion 53c and the connection portion 55c are arranged parallel to each other and separated from each other in the width direction of the wiring member 50.

The joining member 70 exists between the end portion 53 a and the external electrode 13. The end 53a and the external electrode 13 are electrically connected to each other through the conductive particles included in the joining member 70. The joining member 70 exists between the end 55 a and the external electrode 15. The end 55a and the external electrode 15 are electrically connected to each other through the conductive particles included in the joining 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 and 55 and the main surface 51a. The cover 57 is joined (bonded) to the conductor layers 53, 55 and an area of the main surface 51a exposed from the conductor layers 53, 55 with an adhesive layer (not shown). The cover 57 is, for example, a resin layer made of a resin such as a polyimide resin. The cover 57 has a thickness of 25 μm, for example.

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

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

The lead wire 80 includes a bundle 81 of a plurality of core wires and a covering member 82 that covers the bundle 81. In the present embodiment, the lead wire 80 has twelve core wires. The 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 are connected to the ends 53a and 55a of the conductor layers 53 and 55, respectively. The ends of the bundle 81 are connected to the ends 53a and 55a by a conductive adhesive. The 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.

In an electronic device including the vibrating device 100, a sound is generated by vibrating the piezoelectric element 10. Vibration of the piezoelectric element 10 may generate a tactile sensation as well as a sound.

As described above, the piezoelectric element 10 flexurally vibrates so that the piezoelectric element 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 becomes the largest at the center of the main surface 11a in the long side direction (X direction), and both ends of the main surface 11a in the long side direction. Is the smallest. The wiring member 50 is connected to the first region R1 supported by the vibrating portion 1, the second region R2 supported by the supporting portion 3f, and the third region connected to the first region R1 and the second region R2. Region R3. Since the first region R1 is supported by the vibrating section 1, it is displaced along with the displacement of the vibrating section 1. Since the third region R3 is connected to the first region R1, the third region R3 tends to be displaced 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 may hinder the vibration of the piezoelectric element 10.

The wiring member 50 extends along the long side 11c of the main surface 11a of the piezoelectric element body 11 and intersects the short side 11d of the main surface 11a of the piezoelectric element body 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 described above, the displacement amount of the main surface 11a is smallest at both ends of the main surface 11a in the long side direction. Therefore, when the wiring member 50 extends along the short side 11d of the main surface 11a of the piezoelectric element body 11 and intersects with the long side 11c of the main surface 11a of the piezoelectric element body 11, that is, the third Vibration of the third region R3 is suppressed as compared with 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. 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, a play occurs in the third region R3. Therefore, external vibration is suppressed from being transmitted to the piezoelectric element 10 through the wiring member 50. As a result, vibration of the piezoelectric element 10 is less likely to be disturbed, and the amplitude of the piezoelectric element 10 can be further increased.

Since the play is generated in the third region R3, the vibration of the piezoelectric element 10 is less likely to be hindered, and the amplitude of the piezoelectric element 10 can be further increased in that respect as well. Further, the load applied to the joining member 71 by the external vibration and the vibration of the piezoelectric element 10 can be suppressed. Therefore, it is possible to prevent the wiring member 50 from being separated 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 element 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 body 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.

Since the third region R3 has the first curved portion C1 and the second curved portion C2, play occurs in the third region R3. Since the play absorbs the external vibration, the vibration of the piezoelectric element 10 is hard 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, E3 of the wiring member 50 become long, A virtual wall is created in a place other than the case 3, and vacant chamber resonance with large variation is likely to occur. Therefore, the influence of the extending portions E1, E2, E3 in which reverberation (natural frequency) is generated due to the cavity resonance derived from the wiring member 50 becomes large. On the other hand, 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 radii of curvature of the first curved portion C1 and the second curved portion C2 may be longer than the length of each of the extending portions E1, E2, E3.

The bottom portion 3a of the case 3 holds both end portions 1a of the vibrating portion 1 in the X direction. Therefore, the amplitude in the central portion of the vibrating portion 1 in the X direction can be further increased.

The external electrodes 13 and 15 are arranged at the center 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 vibration device 100, the amplitude of the piezoelectric element 10 can be increased.

The present invention is not necessarily limited to the embodiments described above, and various modifications can be made without departing from the spirit of the invention.

FIG. 8 is a partially enlarged cross-sectional view of a vibrating device according to a modification. As shown in FIG. 8, in the vibration device 100A according to the modification, the case 3 is not provided with the recess 3d, and the entire main surface 12b of the vibration member 12 is bonded (bonded) to the bottom 3a by the adhesive layer 60. This is different from the vibrating device 100. Even in this case, the vibration of the piezoelectric element 10 is unlikely to be disturbed.

In the vibrating devices 100 and 100A, the third region R3 of the wiring member 50 may not 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 extending portion E2. In this case, the first bending portion C1 and the second bending portion C2 are directly connected. The third region R3 may not have the third extending portion E3. In this case, the second curved portion and the third region R3 are directly connected. The third region R3 may have at least the first curved portion C1. External vibrations are absorbed by the play generated by the first curved portion C1.

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

DESCRIPTION OF SYMBOLS 1... Vibrating part, 1a... End part, 3a... Bottom part (holding part), 10... Piezoelectric element, 11... Piezoelectric element, 11a... Main surface, 11c... Long side, 11d... Short side, 12... Vibrating member, 13 , 15... External electrode, 19, 21, 23... Internal electrode, 50... Wiring member, 100, 100A... Vibrating device, C1... First curved portion, C2... Second curved portion, R1... First region, R2... Two areas, R3... third area.

Claims (7)

A piezoelectric element having a rectangular main surface, an internal electrode arranged inside the piezoelectric element, and an internal electrode arranged on the main surface and electrically connected to the internal electrode. A vibrating section having a piezoelectric element including an external electrode,
A wiring member connected to the external electrode,
When viewed from 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, a first region supported by the vibrating portion, a second region supported by a supporting portion, a third region connected to the first region and the second region, Have
The vibrating device, wherein the third region includes a curved portion. The vibrating device according to claim 1, wherein the length of the third region in the orthogonal direction is longer than the length of the piezoelectric element body in the orthogonal direction. The vibration device according to claim 2, wherein a radius of curvature of the curved portion is larger than an amplitude of the piezoelectric element. The vibrating device according to any one of claims 1 to 3, further comprising holding portions that hold both end portions of the vibrating portion in a long side direction of the main surface. The vibrating device according to claim 1, wherein the vibrating unit further includes a vibrating member to which the piezoelectric element is joined. The vibrating device according to claim 1, wherein the external electrode is arranged in a central portion of the main surface. An electronic apparatus comprising the vibrating device according to claim 1.