Vibration Devices

Abstract

The present invention provides a vibration device, which includes a piezoelectric element and a vibration component. The vibration component has a first main surface opposite to a substrate and a second main surface opposite to the first main surface and configured with a piezoelectric element. A protrusion is provided on the first main surface of the vibration component, which abuts against the substrate and divides a vibration space on the first main surface. When the vibration component is viewed from a direction orthogonal to the first main surface, the protrusion is located on the outside of the piezoelectric element in a manner of surrounding the piezoelectric element.

Description

Technical Field

[0001] One embodiment of the present invention relates to a vibration device. Background Art

[0002] A known vibration device is supported by a substrate (see, for example, Japanese Patent Application Laid-Open No. 2013-243501). The vibration device includes a piezoelectric element and a vibration component. The vibration component has a first main surface facing the substrate and a second main surface facing the first main surface and having the piezoelectric element arranged thereon.

[0003] In the vibration device described in Japanese Patent Publication No. 2013-243501, the entire vibration component is supported by a substrate. In this case, the substrate may hinder the displacement of the vibration component. In other words, the substrate may hinder the displacement of the vibration component. In the case where the substrate hinders the displacement of the vibration component, the displacement amount of the vibration device will be reduced. Summary of the invention

[0004] An object of one embodiment of the present invention is to provide a vibration device capable of suppressing a reduction in displacement.

[0005] A vibration device of one embodiment is supported by a substrate. The vibration device includes a piezoelectric element and a vibration component. The vibration component has a first main surface opposite to the substrate and a second main surface opposite to the first main surface and on which the piezoelectric element is arranged. A protrusion is provided on the first main surface of the vibration component, which abuts against the substrate and divides a vibration space on the first main surface. When the vibration component is viewed from a direction perpendicular to the first main surface, the protrusion is located on the outside of the piezoelectric element in a manner of surrounding the piezoelectric element.

[0006] According to one of the above-mentioned methods, since the protrusion abuts against the substrate, the vibration device is supported on the substrate at the protrusion. That is, the unit composed of the piezoelectric element and the vibration component is supported on the substrate through the protrusion. Therefore, according to one of the above-mentioned methods, compared with a structure in which the entire vibration component is supported by the substrate, the substrate is less likely to hinder the displacement of the vibration component. In other words, the substrate is less likely to hinder the displacement of the vibration device. As a result, the displacement amount of the vibration device is less likely to decrease. According to one of the above-mentioned methods, the reduction in displacement amount is suppressed.

[0007] When the vibration component is viewed from a direction perpendicular to the first main surface, the protrusion is located outside the piezoelectric element in a manner that surrounds the piezoelectric element. In this structure, the displacement of the vibration device is large compared to a structure in which the protrusion is located inside the outer edge of the piezoelectric element when the vibration component is viewed from a direction perpendicular to the first main surface. Therefore, the reduction in displacement is further suppressed according to the above-mentioned one method.

[0008] A more complete understanding of the present invention will become apparent from the detailed description given hereinafter and the accompanying drawings which are given by way of illustration only and are not to be construed as limiting the present invention.

[0009] Further applicability of the present invention can be seen from the detailed description given below. However, it should be understood that the detailed description and specific examples, while showing the embodiments of the present invention, are only for illustrative considerations, because it is obvious to those skilled in the art that various changes and modifications can be made within the spirit and scope of the present invention based on the detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a perspective view showing a vibration device according to one embodiment.

[0011] Figure 2 It is a plan view showing the vibration device according to the present embodiment.

[0012] Figure 3 It is a plan view showing the vibration device according to the present embodiment.

[0013] Figure 4 It is a diagram showing a cross-sectional structure of the vibration device according to the present embodiment.

[0014] Figure 5 It is a diagram showing a cross-sectional structure of the vibration device according to the present embodiment.

[0015] Figure 6 is a plan view showing a protrusion.

[0016] Figure 7 It is a plan view showing a vibration device according to a modification example of the present embodiment.

[0017] Figure 8 It is a diagram showing a cross-sectional structure of an electronic device according to this embodiment. DETAILED DESCRIPTION

[0018] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, the same elements having the same functions are denoted by the same reference numerals, and repeated explanations are omitted.

[0019] Reference Figure 1 to Figure 6 The structure of the vibration device 1A according to the present embodiment will be described. Figure 1 It is a perspective view showing the vibration device according to the present embodiment. Figure 2 and Figure 3 It is a plan view showing the vibration device according to the present embodiment. Figure 4 and Figure 5 It is a diagram showing a cross-sectional structure of the vibration device according to the present embodiment. Figure 6 is a plan view showing a protrusion.

[0020] like Figure 1 to Figure 4 As shown, the vibration device 1A includes a piezoelectric element 10, a vibration member 20, and a protective layer 30. The piezoelectric element 10 has a piezoelectric base 11 and a pair of external electrodes 13 and 15. In this embodiment, the piezoelectric element 10 does not have an internal electrode disposed inside the piezoelectric base 11.

[0021] The piezoelectric substrate 11 has a disc shape. The piezoelectric substrate 11 has a pair of main surfaces 11a and 11b facing each other and a side surface 11c. The shape and area of ​​the main surface 11a are substantially the same as the shape and area of ​​the main surface 11b. The main surfaces 11a and 11b are circular. In this embodiment, each main surface 11a and 11b is approximately a true circular shape. For example, when the main surface 11a constitutes the third main surface, the main surface 11b constitutes the fourth main surface. The diameter of the main surfaces 11a and 11b is, for example, 5 to 20 mm. In this embodiment, the diameter of the main surfaces 11a and 11b is 10 mm.

[0022] The direction in which the principal surface 11a and the principal surface 11b are opposite to each other is the first direction D1. The first direction D1 is a direction orthogonal to the principal surfaces 11a and 11b. The side surface 11c extends in the first direction D1 in a manner connecting the principal surface 11a and the principal surface 11b. The principal surfaces 11a, 11b and the side surface 11c are indirectly adjacent to each other via an edge portion. The length of the piezoelectric substrate 11 in the first direction D1 (the thickness of the piezoelectric substrate 11) is, for example, 40 to 300 μm. In this embodiment, the thickness of the piezoelectric substrate 11 is 140 μm.

[0023] The piezoelectric substrate 11 is made of a piezoelectric material. In this embodiment, the piezoelectric substrate 11 is made of a piezoelectric ceramic material. The piezoelectric ceramic material is, for example, PZT [Pb (Zr, Ti) O3], PT (PbTiO3), PLZT [(Pb, La) (Zr, Ti) O3] or barium titanate (BaTiO3). The piezoelectric substrate 11 is made of, for example, a sintered body of a ceramic green sheet containing the above-mentioned piezoelectric ceramic material.

[0024] The external electrode 13 is arranged on the main surface 11a. The external electrode 13 is in contact with the main surface 11a. The external electrode 15 is arranged on the main surface 11b. The external electrode 15 is in contact with the main surface 11b. When viewed from the first direction D1, each external electrode 13, 15 is circular in shape. The surface of each external electrode 13, 15 is circular in shape. In this embodiment, each external electrode 13, 15 (the surface of each external electrode 13, 15) is approximately a true circular shape. Each external electrode 13, 15 is composed of a conductive material. The conductive material is, for example, Ag, Pd or Ag-Pd alloy. Each external electrode 13, 15 is composed of a sintered body of a conductive paste containing the above-mentioned conductive material. No electrode is arranged on the side 11c of the piezoelectric substrate 11. Therefore, the entire side 11c is not covered by the electrode and is exposed. For example, in the case where the external electrode 13 constitutes the first electrode, the external electrode 15 constitutes the second electrode.

[0025] The external electrode 13 covers a portion of the main surface 11a. When viewed from the first direction D1, the area of ​​the external electrode 13 is smaller than the area of ​​the main surface 11a. When viewed from the first direction D1, the external electrode 13 is located at a position closer to the inside than the end edge of the main surface 11a. The external electrode 13 is spaced apart from the end edge of the main surface 11a. The main surface 11a has an area covered by the external electrode 13 and an area exposed from the external electrode 13. The area covered by the external electrode 13 is located on the inside of the area exposed from the external electrode 13, and when viewed from the first direction D1, is surrounded by the area exposed from the external electrode 13. The external electrode 13 may also cover the entire main surface 11a.

[0026] The external electrode 15 covers a portion of the main surface 11b. When viewed from the first direction D1, the area of ​​the external electrode 15 is smaller than the area of ​​the main surface 11b. When viewed from the first direction D1, the external electrode 15 is located at a position closer to the inside than the end edge of the main surface 11b. The external electrode 15 is spaced apart from the end edge of the main surface 11b. The main surface 11b has an area covered by the external electrode 15 and an area exposed from the external electrode 15. The area covered by the external electrode 15 is located on the inside of the area exposed from the external electrode 15, and when viewed from the first direction D1, is surrounded by the area exposed from the external electrode 15. The external electrode 15 may also cover the entire main surface 11b.

[0027] The vibration component 20 has a pair of main surfaces 20a and 20b opposite to each other. The direction in which the main surface 20a and the main surface 20b are opposite to each other is also the first direction D1. The first direction D1 is also a direction orthogonal to each main surface 20a and 20b. The vibration component 20 is a sheet-like component. In this embodiment, the vibration component 20 is a vibration sheet. In this case, the vibration component 20 amplifies the vibration of the piezoelectric element 10. The vibration component 20 is made of metal, for example. The vibration component 20 is made of, for example, Ni-Fe alloy, Ni, brass or stainless steel. The vibration component 20 has conductivity. Therefore, each main surface 20a and 20b also has conductivity.

[0028] When viewed from the first direction D1, the vibration component 20 (main surfaces 20a, 20b) is circular in shape. In this embodiment, the vibration component 20 (main surfaces 20a, 20b) is approximately circular in shape. The length of the vibration component 20 in the first direction D1 (the thickness of the vibration component 20) is, for example, 50 to 300 μm. In this embodiment, the vibration component 20 has a thickness of 120 μm. The diameter of the main surfaces 20a, 20b is, for example, 8 to 30 mm. In this embodiment, the diameter of the main surfaces 20a, 20b is 15 mm. For example, when the main surface 20a constitutes the second main surface, the main surface 20b constitutes the first main surface.

[0029] like Figure 5 As shown, the piezoelectric element 10 and the vibration component 20 are bonded together by a resin layer 23. The resin layer 23 bonds the external electrode 13 and the main surface 20a of the vibration component 20 together. The piezoelectric element 10 is arranged on the vibration component 20 in a manner that the external electrode 13 and the main surface 20a are opposite to each other. The external electrode 13 and the main surface 20a are opposite to each other in a state where the resin layer 23 exists between the external electrode 13 and the main surface 20a. The external electrode 13 and the main surface 20a are indirectly opposite to each other. The resin layer 23 is made of, for example, a thermosetting resin, a photocurable resin, or a photothermosetting resin. The resin layer 23 is made of, for example, an epoxy resin, an acrylic resin, or a polyurethane resin.

[0030] When observed from the first direction D1, the area of ​​the piezoelectric element 10 (main surfaces 11a, 11b) is smaller than the area of ​​the vibration component 20 (main surfaces 20a, 20b). When observed from the first direction D1, the piezoelectric element 10 is located at a position closer to the inside than the outer edge of the vibration component 20 (main surface 20a). When observed from the first direction D1, the piezoelectric element 10 is located at the approximate center of the main surface 20a of the vibration component 20. The approximate center of the main surface 20a includes not only the center position of the main surface 20a, but also a position that deviates from the center position of the main surface 20a due to manufacturing errors or intersections. In addition, the approximate center of the main surface 20a also includes a position separated from the center of the main surface 20a by a predetermined small length. The predetermined length is, for example, 5% of the radius of the main surface 20a.

[0031] like Figure 5 As shown, the external electrode 13 and the main surface 20a are in physical contact and electrically connected to each other. The external electrode 13 has a plurality of protrusions 13a. The plurality of protrusions 13a are in physical contact with the main surface 20a. The external electrode 13 and the main surface 20a are electrically connected to each other through the plurality of protrusions 13a. Each protrusion 13a constitutes an electrical connection path between the external electrode 13 and the main surface 20a. The main surface 20a is substantially flat. The thickness of the external electrode 13 is the largest at the position of the protrusion 13a. The maximum thickness of the external electrode 13 is, for example, 5 to 10 μm. In this embodiment, the maximum thickness of the external electrode 13 is 8 μm. The minimum thickness of the external electrode 13 is, for example, 1 to 5 μm. In this embodiment, the minimum thickness of the external electrode 13 is 2 μm. The average thickness of the external electrode 13 is, for example, 4 to 7 μm. In this embodiment, the average thickness of the external electrode 13 is 5 μm.

[0032] The external electrode 13 also has a plurality of protrusions 13b that are not in physical contact with the main surface 20a. The plurality of protrusions 13b are spaced apart from the main surface 20a and are not in physical contact with the main surface 20a. Irregular concavities and convexities are formed on the surface of the external electrode 13 by the protrusions 13a and 13b. The irregular concavities and convexities refer to at least one of irregular changes in the intervals between the peaks of the concavities and convexities and irregular changes in the height difference of the concavities and convexities. As with the surface of the external electrode 13, irregular concavities and convexities may also be formed on the surface of the external electrode 15.

[0033] The resin layer 23 is located between the plurality of protrusions 13a. The resin layer 23 is also located between the plurality of protrusions 13b and the main surface 20a in the first direction D1. The thickness of the resin layer 23 varies depending on the shapes of the protrusions 13a and 13b. Figure 4 and Figure 8 In order to simplify the drawing, the resin layer 23 is omitted.

[0034] The main surface 20a of the vibration component 20 is provided with a protrusion 25. The protrusion 25 is arranged on the main surface 20a. The protrusion 25 divides the vibration space VS on the main surface 20a. When viewed from the first direction D1, the vibration space VS is located inside the protrusion 25. Figure 2 and Figure 3As shown, when the vibration component 20 is seen through from the first direction D1, the protrusion 25 is located on the outside of the piezoelectric element 10 in a manner that surrounds the piezoelectric element 10. When the vibration component 20 is seen through from the first direction D1, the protrusion 25 does not overlap with the piezoelectric element 10. When the vibration component 20 is seen through from the first direction D1, the protrusion 25 is located outside the outer edge of the piezoelectric element 10. When observed from the first direction D1, the protrusion 25 is located inside the end edge of the vibration component 20 (main surface 20a). When observed from the first direction D1, the protrusion 25 is spaced apart from the end edge of the vibration component 20 (main surface 20a).

[0035] When viewed from the first direction D1, the protrusion 25 is annular. Therefore, when the vibration component 20 is viewed from the first direction D1, the protrusion 25 is continuously formed to surround the entire circumference of the piezoelectric element 10. In this embodiment, the protrusion 25 is roughly annular. The protrusion 25 is formed, for example, by curing a resin material. In this case, the protrusion 25 is made of, for example, a phenolic resin, an acrylic resin, a polyvinyl acetal resin, a polyurethane resin, a polyamide resin, an epoxy resin, a styrene resin, or a polyester resin. The protrusion 25 may also be made of metal. In this case, the protrusion 25 may be made of the same metal as the vibration component 20, or may be made of a metal different from the vibration component 20. The protrusion 25 may be integrally formed with the vibration component 20, or may be separately formed with the vibration component 20. When the protrusion 25 is separately formed with the vibration component 20, the protrusion 25 has a surface in contact with the vibration component 20 (main surface 20a).

[0036] The protrusion 25 has an outer edge 25a and an inner edge 25b. Figure 5 As shown, when viewed from the first direction D1, the outer edge 25a and the inner edge 25b are wavy. The wavy shape includes a shape in which wave crests and wave troughs are regularly or irregularly repeatedly formed. The wavy shape may also include a shape in which the width of the protrusion 25 changes regularly or irregularly along the direction in which the protrusion 25 extends. A portion of the outer edge 25a may be wavy, or the entire outer edge 25a may be wavy. A portion of the inner edge 25b may be wavy, or the entire inner edge 25b may be wavy. In the case where a portion of each of the outer edge 25a and the inner edge 25b is wavy, the positions of the wavy portions on the outer edge 25a and the inner edge 25b in the direction in which the protrusion 25 extends may be the same or different.

[0037] The width of the protrusion 25 is, for example, 0.1 to 1.5 mm. In this embodiment, it is about 1 mm. The height of the protrusion 25 is, for example, 50 to 500 μm. In this embodiment, it is about 250 μm. The distance (shortest distance) between the protrusion 25 and the edge of the vibration component 20 (main surface 20a) is, for example, 0 to 2 mm. In this embodiment, it is about 0.5 mm.

[0038] The protective layer 30 is configured to cover the piezoelectric element 10. The protective layer 30 is made of an electrically insulating resin. That is, the protective layer 30 does not contain a conductive filler. The protective layer 30 is formed by curing a resin material. The protective layer 30 is made of, for example, a polyvinyl butyral resin, an acrylic resin, or a polyurethane resin.

[0039] An opening 31 is formed in the protective layer 30. A portion of the external electrode 15 is exposed from the opening 31. The surface of the external electrode 15 has a region 15a covered by the protective layer 30 and a region 15b exposed from the protective layer 30. When viewed from the first direction D1, the region 15b is arranged to be surrounded by the region 15a. The inner edge of the protective layer 30 defines the region 15b. The inner edge of the protective layer 30 forms the opening 31. The shape of the region 15b is defined by the shape of the opening 31. In this embodiment, the region 15b is substantially circular. Except for the region 15b, the piezoelectric element 10 is almost entirely covered by the protective layer 30.

[0040] When viewed from the first direction D1, the region 15b is located approximately at the center of the surface of the external electrode 15. The approximately center of the surface of the external electrode 15 includes not only the center position of the surface, but also a position deviated from the center position of the surface due to manufacturing errors or tolerances. The approximately center of the surface of the external electrode 15 also includes a position separated from the center of the surface by a predetermined small length. The predetermined length is, for example, 10% of the radius of the surface of the external electrode 15. When viewed from the first direction D1, the region 15b may also deviate from the approximately center of the surface of the external electrode 15.

[0041] Next, refer to Figure 7 , a structure of a vibration device 1B according to a modified example of the present embodiment will be described. Figure 7 1 is a plan view showing a vibration device of a modified example of the present embodiment. The vibration device 1B of the present modified example is substantially similar to or identical to the above-mentioned vibration device 1A, but the structure of the protrusion 25 of the present modified example is different from that of the above-mentioned embodiment. In the following, the differences between the above-mentioned embodiment and the modified example will be mainly described.

[0042] Similar to the vibration device 1A, the vibration device 1B includes a piezoelectric element 10, a vibration component 20 and a protective layer 30 (not shown). The protrusion 25 provided on the main surface 20a of the vibration component 20 is provided intermittently. That is, when the vibration component 20 is viewed from the first direction D1, the protrusion 25 is intermittently formed in a manner of surrounding the piezoelectric element 10. The protrusion 25 is intermittently arranged on the main surface 20a. In this modification, the protrusion 25 is composed of a plurality of parts 26. In this embodiment, the protrusion 25 is composed of five parts 26. The parts 26 are spaced apart from each other on the main surface 20a. When viewed from the first direction D1, the parts 26 are roughly arc-shaped. The protrusion 25 may be composed of four or less parts 26, or may be composed of six or more parts 26.

[0043] The plurality of portions 26 define a vibration space VS on the main surface 20a. Figure 7 As shown, when the vibration component 20 is viewed from the first direction D1, the plurality of parts 26 are located outside the piezoelectric element 10 in a manner of surrounding the piezoelectric element 10. When the vibration component 20 is viewed from the first direction D1, the plurality of parts 26 do not overlap with the piezoelectric element 10. When viewed from the first direction D1, the plurality of parts 26 are located inside the end edge of the vibration component 20 (main surface 20a). When viewed from the first direction D1, the plurality of parts 26 are spaced apart from the end edge of the vibration component 20 (main surface 20a).

[0044] Next, refer to Figure 8 The structure of the electronic device ED according to this embodiment will be described. Figure 8 It is a diagram showing a cross-sectional structure of an electronic device according to this embodiment.

[0045] like Figure 8 As shown, the electronic device ED includes a substrate 41, an operation panel 43, a vibration device 1A, and a wiring component 50. The electronic device ED may also include a vibration device 1B instead of the vibration device 1A. The vibration device 1A is arranged between the substrate 41 and the operation panel 43. The vibration device 1A vibrates the operation panel 43. The operation panel 43 vibrates relative to the substrate 41. The operation panel 43 constitutes, for example, a vibrated component.

[0046] The wiring component 50 is electrically connected to the piezoelectric element 10. The wiring component 50 is arranged between the operation panel 43 and the vibration device 1A. The wiring component 50 is arranged in the vibration device 1A in a manner opposite to the piezoelectric element 10. The wiring component 50 and the piezoelectric element 10 are opposite to each other in a state where the protective layer 30 exists between the wiring component 50 and the piezoelectric element 10. The wiring component 50 and the piezoelectric element 10 are indirectly opposite to each other. The wiring component 50 is in contact with the operation panel 43. The wiring component 50 is, for example, an FPC (flexible printed circuit).

[0047] The wiring component 50 has a plurality of wirings 51, 53. In this embodiment, the wiring component 50 has two wirings 51, 53. The wiring 51 is electrically connected to the external electrode 15. The wiring 51 is electrically and physically connected to the external electrode 15 through a conductive resin 55. The conductive resin 55 is disposed between the wiring 51 and the external electrode 15 (region 15b) and is in contact with the wiring 51 and the external electrode 15 (region 15b). The wiring 53 is electrically connected to the main surface 20b of the vibration component 20. The wiring 53 is electrically and physically connected to the main surface 20b through a conductive resin 57. The conductive resin 57 is disposed between the wiring 53 and the main surface 20a and is in contact with the wiring 53 and the main surface 20b. The wiring 53 is electrically connected to the external electrode 13 through the conductive resin 57 and the vibration component 20. The conductive resins 55, 57 include, for example, resin and conductive filler. The resin is, for example, a thermosetting resin. The conductive filler is, for example, metal particles or metal-plated particles. The metal particles are, for example, Ag particles or Cu particles. The metal-plated particles are, for example, gold-plated particles. The thermosetting resin is, for example, phenolic resin, acrylic resin, silicone resin, epoxy resin, or polyimide resin.

[0048] The vibration device 1A is arranged on the substrate 41 in such a manner that the main surface 20a of the vibration component 20 is opposite to the substrate 41. The protrusion 25 is in contact with the substrate 41. The thickness of the vibration space VS, that is, the length of the vibration space VS in the first direction D1 is determined by the height of the protrusion 25. In the electronic device ED, the vibration space VS is divided by the vibration component 20 (main surface 20a), the protrusion 25 and the substrate 41. The thickness of the vibration space VS is greater than the displacement of the vibration component 20. The displacement of the vibration component 20 is the unilateral amplitude of the vibration of the vibration component 20, that is, 1 / 2 of the total amplitude of the vibration of the vibration component 20.

[0049] The vibration device 1A and the wiring component 50 are sandwiched between the substrate 41 and the operation panel 43. As a result, the vibration device 1A is supported by the substrate 41 at the protrusion 25. That is, the vibration unit composed of the piezoelectric element 10 and the vibration component 20 is supported on the substrate 41 through the protrusion 25. In this embodiment, the protrusion 25 is not fixed to the substrate 41, and the wiring component 50 is not fixed to the operation panel 43. The wiring component 50 may also be fixed to the operation panel 43.

[0050] Wiring 51, 53 is connected to a control unit (not shown). The control unit is electrically connected to the piezoelectric element 10 through the wiring component 50, and generally controls the vibration device 1A. The control unit includes, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory). In this case, the control unit performs various processes by loading the program stored in the ROM into the RAM and executing it by the CPU.

[0051] The vibration unit composed of the piezoelectric element 10 and the vibration component 20 is supported on the substrate 41 through the protrusion 25. Therefore, the piezoelectric element 10 is used together with the vibration component 20 in a bendable state. For example, when the fingertip of the user of the electronic device ED contacts the operation panel 43 and bends the piezoelectric element 10, the piezoelectric element 10 provides a detection signal to the control unit. Once the control unit receives the detection signal, it provides a drive signal to the piezoelectric element 10 to drive the piezoelectric element 10. The piezoelectric element 10 vibrates based on the drive signal. The piezoelectric element 10 constitutes a detection element and a drive element.

[0052] The control unit applies AC voltages with different polarities to the external electrodes 13 and 15 as drive signals through the wirings 51 and 53 of the wiring member 50. When the AC voltages with different polarities are applied to the external electrodes 13 and 15, an electric field is generated between the external electrodes 13 and 15. The area of ​​the piezoelectric substrate 11 sandwiched between the external electrodes 13 and 15 becomes an active area, and displacement occurs in the active area. The piezoelectric element 10 repeatedly stretches and contracts according to the frequency of the AC voltage.

[0053] Since the piezoelectric element 10 and the vibration component 20 are bonded to each other, the vibration component 20 flexes and vibrates integrally with the piezoelectric element 10 in response to repeated stretching and contraction of the piezoelectric element 10. As a result, the vibration device 1A produces a tactile sensation to the user. The tactile sensation is, for example, a click tactile sensation. The click tactile sensation is, for example, a pressing tactile sensation or a touching tactile sensation obtained when a push button switch is pressed.

[0054] As described above, the vibration devices 1A and 1B include the piezoelectric element 10 and the vibration member 20. The protrusions 25 provided on the principal surface 20a of the vibration member 20 are in contact with the base material 41 and define the vibration space VS on the principal surface 20a.

[0055] In the vibration devices 1A and 1B, the protrusion 25 abuts against the substrate 41, so the vibration devices 1A and 1B are supported on the base 41 at the protrusion 25. That is, the vibration unit composed of the piezoelectric element 10 and the vibration component 20 is supported on the substrate 41 through the protrusion 25. Therefore, in the vibration devices 1A and 1B, compared with the structure in which the entire vibration component 20 is supported by the substrate 41, the substrate 41 is not easy to hinder the displacement of the vibration devices 1A and 1B. That is, although the vibration devices 1A and 1B are supported by the substrate 41, the substrate 41 is not easy to hinder the displacement of the vibration devices 1A and 1B. As a result, it is difficult to reduce the displacement amount of the vibration devices 1A and 1B. The vibration devices 1A and 1B can suppress the reduction in the displacement amount.

[0056] When the vibration component 20 is seen through from the first direction D1, the protrusion 25 is arranged outside the piezoelectric element 10 in a manner of surrounding the piezoelectric element 10. In this structure, the displacement of the vibration devices 1A and 1B is large compared to a structure in which the protrusion 25 is located inside the outer edge of the piezoelectric element 10 when the vibration component 20 is seen through from the first direction D1. Therefore, the vibration devices 1A and 1B further suppress the reduction in displacement.

[0057] In the vibration devices 1A and 1B, the protrusion 25 is located inside the edge of the vibration member 20 (the main surface 20 a ) when viewed from the first direction D1 . In this case, the vibration devices 1A and 1B produce the following effects.

[0058] In a structure in which a protrusion 25 made of an electrically insulating material is located at the end edge of the vibration component 20, when the protrusion 25 is formed, the electrically insulating material constituting the protrusion 25 may adhere to the main surface 20b. The electrically insulating material is, for example, a resin that does not contain a conductive filler. If the electrically insulating material constituting the protrusion 25 adheres to the main surface 20b, it may hinder the electrical connection between the wiring 53 and the main surface 20b. In contrast, in the vibration devices 1A and 1B, the electrically insulating material constituting the protrusion 25 is difficult to adhere to the main surface 20b. Therefore, the vibration devices 1A and 1B can establish a good electrical connection between the wiring 53 and the main surface 20b.

[0059] In a structure in which a protrusion 25 made of metal is located at the end edge of the vibration component 20, the end edge of the vibration component 20 may be deformed when the protrusion 25 is formed. If the end edge of the vibration component 20 is deformed, the vibration component 20 may vibrate inappropriately. When the protrusion 25 is formed integrally with the vibration component 20 made of metal, the end edge of the vibration component 20 is more likely to be deformed. In contrast, in the vibration devices 1A, 1B, the end edge of the vibration component 20 is not easily deformed. Therefore, in the vibration devices 1A, 1B, the vibration component 20 vibrates appropriately.

[0060] In the vibration devices 1A and 1B, the thickness of the vibration space VS is greater than the displacement of the vibration component 20. Therefore, even when the vibration component 20 vibrates, it is difficult for the vibration component 20 to contact the substrate 41. As a result, it is difficult for the substrate 41 to hinder the vibration of the vibration devices 1A and 1B. The vibration devices 1A and 1B appropriately give the user a sense of touch.

[0061] In the vibration device 1B, the protrusions 25 are provided intermittently. In this case, the vibration of the vibration member 20 is less likely to be hindered by the protrusions 25. Therefore, the displacement amount of the vibration member 20 increases, and the vibration device 1B provides a more appropriate tactile feeling to the user.

[0062] In the vibration devices 1A, 1B, when viewed from the first direction D1, the outer edge 25 a and the inner edge 25 b of the protrusion 25 are wavy.

[0063] When stress acts on the protrusion 25 from the vibration component 20 and the substrate 41, the protrusion 25 may be damaged. When the outer edge 25a and the inner edge 25b of the protrusion 25 are wavy when viewed from the first direction D1, the stress from the vibration component 20 and the substrate 41 is dispersed. Therefore, the stress acting from the vibration component 20 and the substrate 41 is less likely to be concentrated on the protrusion 25. As a result, in the vibration devices 1A, 1B, the protrusion 25 is less likely to be damaged.

[0064] In the vibration devices 1A and 1B, the protection layer 30 is arranged so as to cover the piezoelectric element 10. Therefore, the protection layer 30 can suppress the entry of moisture into the piezoelectric element 11. As a result, the vibration devices 1A and 1B suppress the degradation of the electrical characteristics of the piezoelectric element 10.

[0065] The wiring component 50 is not fixed to the operating panel 43. That is, the vibration devices 1A and 1B are not fixed to the operating panel 43. In this case, the operating panel 43 is unlikely to hinder the displacement of the vibration devices 1A and 1B. Therefore, in this embodiment, the displacement amount of the vibration devices 1A and 1B is difficult to reduce. As a result, the vibration devices 1A and 1B provide the user with a more appropriate touch.

[0066] Although the embodiment and the modified example of the present invention have been described above, the present invention is not necessarily limited to the embodiment and the modified example, and various changes may be made to the embodiment without departing from the scope of the present invention.

[0067] In this embodiment, when viewed from the first direction D1, the protrusion 25 is substantially annular, but the shape of the protrusion 25 is not limited to a substantially annular shape. When viewed from the first direction D1, the protrusion 25 may also be substantially a polygonal ring. In this modified example, when viewed from the first direction D1, each portion 26 is substantially arc-shaped, but the shape of each portion 26 is not limited to an arc-shaped. When viewed from the first direction D1, each portion 26 may extend in a straight line, a wave, or a zigzag shape.

[0068] The shapes of the piezoelectric substrate 11, the external electrodes 13, 15, and the vibration member 20 are not limited to the above shapes. For example, the piezoelectric substrate 11, the external electrodes 13, 15, and the vibration member 20 may be polygonal in plan view.

[0069] The piezoelectric element 10 may have one or more internal electrodes arranged in the piezoelectric base 11. In this case, the piezoelectric base 11 may have a plurality of piezoelectric base layers, and the internal electrodes and the piezoelectric base layers may be alternately arranged.

[0070] When the protrusion 25 is made of resin, a plurality of hollow holes may be distributed in the protrusion 25 .

[0071] The piezoelectric element 10 constitutes both a detection element and a driving element, but may constitute only a driving element.

[0072] The electronic device ED may include a display panel or a housing instead of the operation panel 43. In this case, the display panel and the housing constitute a vibrated member.

Claims

1. A vibrating device supported by a substrate, characterized in that: include: Piezoelectric elements; and a vibration component having a first main surface opposite to the substrate and a second main surface opposite to the first main surface and on which the piezoelectric element is arranged, The first main surface of the vibration component is provided with a protrusion that contacts the base material and defines a vibration space on the first main surface. When the vibration component is viewed from a direction perpendicular to the first main surface, the protrusion is located outside the piezoelectric element so as to surround the piezoelectric element. The piezoelectric element includes: a piezoelectric substrate, and a first electrode and a second electrode disposed on the piezoelectric substrate. The piezoelectric substrate includes: a third main surface opposite to the second main surface, a fourth main surface opposite to the third main surface, and a side surface connecting the third main surface and the fourth main surface. The side surface is exposed from the first electrode and the second electrode.

2. The vibration device according to claim 1, characterized in that A thickness of the vibration space in the direction orthogonal to the first main surface is larger than a displacement amount of the vibration member.

3. The vibration device according to claim 1 or 2, characterized in that: The protrusions are disposed intermittently.

4. The vibration device according to any one of claims 1 to 3, characterized in that The protrusion has a wavy edge when viewed from the direction perpendicular to the first main surface.

5. The vibration device according to claim 1, characterized in that The first electrode is arranged on the third main surface, The second electrode is arranged on the fourth main surface.

6. The vibration device according to claim 1, characterized in that The piezoelectric substrate is not in direct contact with the vibration component.

7. The vibration device according to claim 1, characterized in that When viewed from a direction perpendicular to the fourth main surface, an area of ​​the second electrode is smaller than an area of ​​the fourth main surface.

8. The vibration device according to claim 1, characterized in that The second electrode is located inside an edge of the fourth main surface when viewed from a direction perpendicular to the fourth main surface.

9. The vibration device according to claim 1, characterized in that The vibration component has conductivity.

10. The vibration device according to any one of claims 1 to 9, characterized in that: The vibration device further includes a wiring member electrically connected to the piezoelectric element, The second main surface of the vibration component has conductivity, The first electrode is electrically connected to the second main surface, The wiring member includes wiring electrically connected to the second main surface and wiring electrically connected to the second electrode.

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