Vibration device

Abstract

To provide a vibration device capable of outputting a vibration with a long wavelength, while avoiding a transmission loss of a vibration between a piezoelectric device and a vibrator.SOLUTION: A vibration device comprises: a vibrator 2 including a piezoelectric device 3; and a vibration body 4 that is fixed so as to be overlapped on the vibrator 2 via a fixing part 5. The fixing part 5 includes: a first fixing part 5A positioned at a center side in a plan view of the vibrator 2 and the vibration body 4; and a second fixing part 5B positioned to the side outer from the fixing part 5. The deformation tolerance of the vibrator 2 and the vibration body 4 by the second fixing part 5B is larger than that of the vibrator 2 and the vibration body 4 by the first fixing part 5A.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to vibration devices. [Background technology]

[0002] An example of a conventional vibration device is the transparent speaker described in Patent Document 1. This transparent speaker is constructed by fixing a piezoelectric element having transparent electrodes on both sides to a vibrating body in a unimorph or bimorph configuration. The lead portion of the transparent electrode on the front side wraps around to the back side while being electrically insulated from the transparent electrode on the back side. A pair of lead wires made of conductive transparent resin or transparent electrode material are arranged on the vibrating body and are electrically connected to each of the transparent electrodes on the front and back sides. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 4-70100 Summary of the Invention [Problem to be solved by the invention]

[0004] Vibration devices using piezoelectric elements such as those described above generally have difficulty outputting vibrations with long wavelengths (i.e., low frequencies). In order to increase the output of vibrations with long wavelengths, it is possible to devise a coupling structure between the piezoelectric element and the vibrating body, but it is also necessary to consider the transmission loss of vibrations between the piezoelectric element and the vibrating body.

[0005] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a vibration device that is capable of outputting vibrations with long wavelengths while avoiding vibration transmission loss between a piezoelectric element and a vibrating body. [Means for solving the problem]

[0006] A vibration device according to one aspect of the present disclosure comprises a vibrator including a piezoelectric element and a vibrating body fixed so as to overlap the vibrator via a fixing portion, the fixing portion having a first fixing portion located toward the center when viewed in a plane of the vibrator and the vibrating body, and a second fixing portion located outside the first fixing portion, and the deformation tolerance of the vibrator and the vibrating body due to the second fixing portion is greater than the deformation tolerance of the vibrator and the vibrating body due to the first fixing portion.

[0007] In this vibration device, by reducing the deformation tolerance of the first fixed portion on the central side, vibrations generated by the vibrator can be transmitted to the vibrating body with reduced loss. Meanwhile, by ensuring the deformation tolerance of the second fixed portion on the outer side, the vibrating body can be vibrated over a wider range. As a result, even when the vibrator vibrates at the same frequency, it is easier to output vibrations with long wavelengths compared to when the entire surface of the vibrator is fixed to the vibrating body with a fixed portion that has low deformation tolerance. Therefore, this vibration device can output vibrations with long wavelengths while avoiding vibration transmission loss between the piezoelectric element and the vibrating body.

[0008] The second fixing portion may be spaced apart from the first fixing portion. In this case, it is possible to suppress the transmission of short-wavelength vibrations from the vibrator to the vibrating body. Therefore, it is possible to construct a vibration device that emphasizes low-pitched sounds.

[0009] The second fixed parts may be arranged in pairs on either side of the first fixed part. This allows the vibrator to vibrate over a wider range, making it easier to output vibrations with long wavelengths.

[0010] The second fixing portion may be disposed so as to overlap the edge of the vibrator, which allows the vibrator to vibrate over a wider range, making it easier to output vibrations with long wavelengths.

[0011] The second fixing portion may be disposed so as to extend outward beyond the edge of the vibrator. This allows the vibrator to vibrate over a wider range, making it easier to output vibrations with long wavelengths.

[0012] In the second fixing portion, the area of ​​the region located outside the edge of the vibrator may be larger than the area of ​​the region located inside the edge of the vibrator. This allows the vibrator to vibrate over a wider range, making it easier to output vibrations with long wavelengths.

[0013] The first fixing portion may be located inside the edge of the vibrator and spaced apart from the edge of the vibrator, in which case vibrations generated by the vibrator can be transmitted to the vibrating body with even less loss.

[0014] The thickness of the first fixed portion and the thickness of the second fixed portion may be equal to each other, in which case the vibrator and vibrating body are initially stress-free, enabling ideal vibration output in response to input.

[0015] The facing area between the first fixing part and the vibrator may be larger than the facing area between the second fixing part and the vibrator. In this case, the vibrator is fixed to the vibrating body with a sufficient area, so that vibrations generated by the vibrator can be transmitted to the vibrating body with even less loss.

[0016] The first fixing portion may be formed of double-sided tape, and the second fixing portion may be formed of a sponge and double-sided tape provided on both sides of the sponge. This makes it possible, with a simple configuration, to create a difference in the deformation tolerance of the vibrator and vibrating body due to the first fixing portion and the deformation tolerance of the vibrator and vibrating body due to the second fixing portion.

[0017] A weight member may be fixed to the vibrator with its center aligned with the first fixing portion. In this case, the vibration of the vibrator can be amplified by the inertia of the weight member. Therefore, the output of the vibratory device can be increased. [Effects of the Invention]

[0018] According to the present disclosure, it is possible to output vibrations with long wavelengths while avoiding transmission loss of vibrations between the piezoelectric element and the vibrating body. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a schematic cross-sectional view showing a vibration device according to an embodiment of the present disclosure. [Figure 2] 2 is a schematic plan view showing a main part of the vibration device shown in FIG. 1. FIG. [Figure 3] 1A is a schematic diagram showing the state of a vibration device according to a comparative example when vibrating, and FIG. 1B is a schematic diagram showing the state of a vibration device according to this embodiment when vibrating. [Figure 4] 10(a) to 10(c) are schematic plan views showing the main parts of a vibration device according to a modified example of the present disclosure. [Figure 5] 10A and 10B are diagrams showing the results of an evaluation test of the output sound pressure of the vibration device. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, preferred embodiments of a vibration device according to one aspect of the present disclosure will be described in detail with reference to the drawings.

[0021] FIG. 1 is a schematic cross-sectional view showing a vibration device according to an embodiment of the present disclosure. FIG. 2 is a schematic plan view showing a main part of the vibration device shown in FIG. 1. For convenience of explanation, a weight member 9 and its fixing portion 10, which will be described later, are omitted from FIG. 2. The vibration device 1 shown in FIGS. 1 and 2 is configured as an acoustic device such as a speaker. The vibration device 1 is incorporated into an external device such as a headset or a head-up display, and functions as an audio output unit for the device.

[0022] As shown in FIGS. 1 and 2, the vibration device 1 includes a vibrator 2 including a piezoelectric element 3, and a vibrating body 4 fixed to overlap the vibrator 2 via a fixing portion 5. In this embodiment, the vibrator 2 includes the piezoelectric element 3 and a wiring member (not shown). The vibrator 2 has, for example, a rectangular shape in a plan view. The vibrator 2 may be either a unimorph type or a bimorph type. In addition to the piezoelectric element 3, the vibrator 2 may further include a diaphragm (a diaphragm separate from the diaphragm 4) made of resin or metal.

[0023] In this embodiment, the piezoelectric element 3 has a rectangular parallelepiped shape that is flat in the thickness direction. The rectangular parallelepiped shape may include a shape in which the corners and ridges are chamfered or a shape in which the corners and ridges are rounded. The piezoelectric element 3 has a piezoelectric element, an internal electrode, and a pair of external electrodes. The piezoelectric element is configured as a laminate of multiple piezoelectric layers. Each piezoelectric layer is formed of a piezoelectric material such as a piezoelectric ceramic and is laminated alternately with the internal electrodes. Examples of piezoelectric ceramic materials include PZT [Pb(Zr,Ti)O3], PT(PbTiO3), PLZT [(Pb,La)(Zr,Ti)O3], and barium titanate (BaTiO3).

[0024] Each piezoelectric layer is made of, for example, a sintered ceramic green sheet containing the above-mentioned piezoelectric ceramic. In an actual piezoelectric element, the piezoelectric layers are integrated to the extent that the boundaries between the layers are indistinguishable. A plurality of internal electrodes (not shown) are disposed within the piezoelectric element. Each internal electrode is made of a conductive material. Examples of conductive materials include Ag, Pd, and Ag-Pd alloys.

[0025] The wiring member is a member that electrically connects the piezoelectric element 3 to an external device. For example, a flexible printed circuit (FPC) is used as the wiring member. One end of the wiring member is electrically connected to each of a pair of external electrodes of the piezoelectric element 3. For example, an anisotropic conductive adhesive can be used to connect the wiring member to the external electrodes. The other end of the wiring member is drawn out from the piezoelectric element and electrically connected to the external device.

[0026] The vibrating body 4 is a plate- or sheet-shaped member made of, for example, metal, resin, paper, etc. Examples of metal materials include Ni-Fe alloy, Ni, brass, and stainless steel. Examples of resin materials include polyvinyl chloride and polycarbonate. The planar shape of the vibrating body 4 is not particularly limited, and various shapes such as rectangular and circular can be used. The area of ​​the vibrating body 4 is sufficiently larger than the area of ​​the vibrator 2. The vibrating body 4 vibrates when the vibrator 2 (piezoelectric element 3) moves in the thickness direction, and outputs sound based on a predetermined vibration frequency.

[0027] The vibrating body 4 is fixed to overlap the vibrator 2 via a fixing portion 5. As shown in Fig. 2, the fixing portion 5 is composed of a first fixing portion 5A located toward the center in a plan view of the vibrator 2 and the vibrating body 4, and a second fixing portion 5B located outside the first fixing portion 5A.

[0028] The deformation tolerance of the vibrator 2 and the vibrating body 4 due to the second fixing portion 5B is greater than the deformation tolerance of the vibrator 2 and the vibrating body 4 due to the first fixing portion 5A. Here, the deformation tolerance can also be rephrased as the restraining force between the vibrator 2 and the vibrating body 4 by the fixing portion 5. In this embodiment, in order to create such a difference in deformation tolerance, the Young's modulus of the first fixing portion 5A is greater than the Young's modulus of the second fixing portion 5B.

[0029] Specifically, in this embodiment, first fixing portion 5A is formed by double-sided tape 6, and second fixing portion 5B is formed by providing double-sided tape 8 on both sides of an elastic member such as sponge 7. In the example of FIG. 2, first fixing portion 5A and second fixing portion 5B have the same thickness. The thicknesses of first fixing portion 5A and second fixing portion 5B do not need to be strictly the same, and differences in thickness due to manufacturing errors or the like are acceptable.

[0030] In the second fixing portion 5B, the thickness of the sponge 7 is greater than the total thickness of the double-sided tape 8 on both sides of the sponge 7. In order to make the thickness of the first fixing portion 5A and the second fixing portion 5B the same, the total thickness of the double-sided tape 8 on both sides of the sponge 7 is less than the thickness of the double-sided tape 6 that constitutes the first fixing portion 5A.

[0031] As shown in FIG. 2 , in a plan view of the vibrator 2 and the vibrating body 4, the first fixing portion 5A and the second fixing portion 5B are both rectangular. Here, the center position of the first fixing portion 5A coincides with the center position of the vibrator 2, and the first fixing portion 5A fixes the central portion of the vibrator 2 to the vibrating body 4. The first fixing portion 5A is spaced apart from the edge of the vibrator 2 and is located inside the edge of the vibrator 2. The extension direction of the long side 5a of the first fixing portion 5A is aligned with the extension direction of the short side 2b of the vibrator 2, and the extension direction of the short side 5b of the first fixing portion 5A is aligned with the extension direction of the long side 2a of the vibrator 2. The long side 5a of the first fixing portion 5A is located inside the short side 2b of the vibrator 2, and the short side 5b of the first fixing portion 5A is located inside the long side 2a of the vibrator 2.

[0032] 1, in this embodiment, a weight member 9 is fixed to the vibrator 2 with its center aligned with that of the first fixed portion 5A. The weight member 9 is formed into a plate shape, for example, from metal or resin, and is fixed to the vibrator 2 on the side opposite the vibrating body 4 via a fixed portion 10. In a plan view of the vibrator 2 and the vibrating body 4, the weight member 9 has a rectangular shape that is, for example, slightly smaller than the first fixed portion 5A. In a plan view of the vibrator 2 and the vibrating body 4, the fixed portion 10 has a rectangular shape with the same dimensions as the first fixed portion 5A, for example, and overlaps the same area as the first fixed portion 5A.

[0033] The second fixing portions 5B are arranged in a pair on either side of the central first fixing portion 5A. Here, the second fixing portions 5B are arranged along the short sides 2b of the vibrator 2 while being spaced apart from the first fixing portion 5A, and the second fixing portions 5B fix the ends of the vibrator 2 in the extension direction of the long sides 2a to the vibrating body 4. The second fixing portions 5B are arranged to overlap the edges of the vibrator 2, i.e., the short sides 2b, and further to protrude outward beyond the short sides 2b. Between the first fixing portion 5A and the second fixing portion 5B, the vibrator 2 is not fixed by the fixing portions 5A and is able to vibrate freely.

[0034] The extension direction of the long side 5c of the second fixed portion 5B is along the extension direction of the short side 2b of the vibrator 2, and the extension direction of the short side 5d of the second fixed portion 5B is along the extension direction of the long side 2a of the vibrator 2. One of the long sides 5c of the second fixed portion 5B is located inside the short side 2b of the vibrator 2 and faces one of the long sides 5a of the first fixed portion 5A at a predetermined distance in the extension direction of the long side 2a of the vibrator 2. The other long side 5c of the second fixed portion 5B is located outside the short side 2b of the vibrator 2. The short side 5d of the second fixed portion 5B is located inside the long side 2a of the vibrator 2 in the extension direction of the short side 2b of the vibrator 2.

[0035] In this embodiment, the position of the short side 5d of the second fixed portion 5B in the extension direction of the short side 2b of the vibrator 2 is aligned with the position of the short side 5b of the first fixed portion 5A. The short side 5d of the second fixed portion 5B is located inside the extension line of the long side 2a of the vibrator 2 in the extension direction of the short side 2b of the vibrator 2. The four corners D of the vibrator 2 do not overlap with the second fixed portion 5B in a plan view of the vibrator 2 and the vibrating body 4, and these corners D can vibrate freely.

[0036] 2, the facing area between the first fixed part 5A and the vibrator 2 (i.e., the area R1 where the first fixed part 5A and the vibrator 2 overlap when the vibrator 2 and the vibrating body 4 are viewed in plan) is larger than the facing area between the second fixed part 5B and the vibrator 2 (i.e., the area R2 where the second fixed part 5B and the vibrator 2 overlap when the vibrator 2 and the vibrating body 4 are viewed in plan). Also, in the second fixed part 5B, the area R3 of the area located outside the edge of the vibrator 2 is larger than the area of ​​the area located inside the edge of the vibrator 2 (i.e., the above-mentioned area R2).

[0037] In the resonator device 1 having the above configuration, by reducing the deformation tolerance of the first fixing portion 5A on the central side, the vibration generated in the vibrator 2 can be transmitted to the vibrating body 4 with reduced loss. On the other hand, by ensuring the deformation tolerance of the second fixing portion 5B on the outer side, the vibrating body 4 can vibrate over a wider range. For example, as shown in FIG. 3(a), in a comparative example resonator device 101 in which the entire surface of the vibrator 102 is fixed to the vibrating body 104 by the fixing portion 105 (double-sided tape), the restraining force of the vibrator 102 to the vibrating body 104 by the fixing portion 105 is strong. Therefore, when the vibrator 102 vibrates at a predetermined vibration frequency, the vibrating body 104 vibrates with a large curvature in a range L1 similar to that of the vibrator 102, making it difficult to output vibrations with long wavelengths.

[0038] In contrast, in the resonator device 1 of this embodiment, as shown in Fig. 3(b), the central portion of the vibrator 2 is strongly constrained by the first fixing portion 5A, while the second fixing portion 5B, which has a greater deformation tolerance than the first fixing portion 5A, weakens the constraining force at both ends of the vibrator 2 compared to the constraining force at the central portion. As a result, even when the vibrator 2 vibrates at the same frequency as in Fig. 3(a), the vibrating body 104 vibrates with a smaller curvature over a wider range L2 than the vibrator 102, making it easier to output vibrations with long wavelengths. Therefore, in this resonator device 1, it is possible to output vibrations with long wavelengths while avoiding vibration transmission loss between the piezoelectric element 3 and the vibrating body 4.

[0039] In this embodiment, the second fixing portion 5B is spaced apart from the first fixing portion 5A. With this configuration, it is possible to suppress transmission of short-wavelength vibrations from the vibrator 2 to the vibrating body 4. Therefore, it is possible to construct a vibration device 1 that places emphasis on low-pitched sounds.

[0040] In this embodiment, a pair of second fixing portions 5B are arranged to sandwich the first fixing portion 5A. The second fixing portions 5B are arranged to overlap the edges of the vibrator 2 and to extend outward beyond the edges of the vibrator 2. This allows the vibrating body 4 to vibrate over a wider range due to the vibration of the vibrator 2. This makes it easier to output vibrations with long wavelengths.

[0041] In this embodiment, the area R3 of the region located outside the edge of the vibrator 2 in the second fixed portion 5B is larger than the area R2 of the region located inside the edge of the vibrator 2. This configuration allows the vibrating body 4 to vibrate over a wider range, making it easier to output vibrations with long wavelengths.

[0042] In this embodiment, the first fixing portion 5A is located away from the edge of the vibrator 2 and inside the edge of the vibrator 2. With this configuration, the vibration generated in the vibrator 2 can be transmitted to the vibrating body 4 with even less loss.

[0043] In this embodiment, the thickness of the first fixed portion 5A and the thickness of the second fixed portion 5B are equal to each other, which makes the vibrator 2 and the vibrating body 4 stress-free in the initial state, enabling ideal vibration output in response to input.

[0044] In this embodiment, the facing area between the first fixed portion 5A and the vibrator 2 may be larger than the facing area between the second fixed portion 5B and the vibrator 2. This allows the vibrator 2 to be fixed to the vibrating body 4 with a sufficient area, so that the vibration generated in the vibrator 2 can be transmitted to the vibrating body 4 with even less loss.

[0045] In this embodiment, the first fixing portion 5A is configured with double-sided tape 6, and the second fixing portion 5B is configured with a sponge 7 and double-sided tapes 8, 8 provided on both sides of the sponge 7. This makes it possible, with a simple configuration, to create a difference between the deformation tolerance of the vibrator 2 and the vibrating body 4 due to the first fixing portion 5A and the deformation tolerance of the vibrator 2 and the vibrating body 4 due to the second fixing portion 5B.

[0046] In this embodiment, the weight member 9 is fixed to the vibrator 2 with its center aligned with the first fixed portion 5A. This allows the vibration of the vibrator 2 to be amplified by the inertia of the weight member 9. This increases the output of the vibratory device 1. [Variations]

[0047] The present disclosure is not limited to the above-described embodiment. For example, in the above-described embodiment, the second fixed portion 5B extends along the extension direction of the short side 2b of the vibrator 2. However, as shown in FIG. 4(a), the second fixed portion 5B may be divided into a plurality of portions along the extension direction of the short side 2b of the vibrator 2. Furthermore, the second fixed portion 5B does not necessarily have to be disposed so as to protrude outward from the edge of the vibrator 2. As shown in FIG. 4(b), in a plan view of the vibrator 2 and the vibrating body 4, the other of the long sides 5c of the second fixed portion 5B may coincide with the short side 2b of the vibrator 2. Although not shown, the other of the long sides 5c of the second fixed portion 5B may be located inside the short side 2b of the vibrator 2.

[0048] Furthermore, second fixed portion 5B does not necessarily have to be spaced apart from first fixed portion 5A, and as shown in Fig. 4(c), long side 5a of first fixed portion 5A may be in contact with one of long sides 5c of second fixed portion 5B. In the embodiment of Fig. 4(c), the opposing area between second fixed portion 5B and vibrator 2 is larger than the opposing area between first fixed portion 5A and vibrator 2, and such an embodiment may also be included in the present disclosure. [Vibration device evaluation test]

[0049] In this evaluation test, samples of vibration devices according to the examples and comparative examples were prepared, and the output sound pressure level (SPL) of each sample was measured. In Example 1, similar to the configuration shown in FIG. 2, a vibrator including a piezoelectric element was fixed to a vibrating body by a first fixing portion in the center and a pair of second fixing portions sandwiching the first fixing portion. The first fixing portion was formed by double-sided tape, and the second fixing portion was formed by a sponge and double-sided tape provided on both sides of the sponge. In Example 2, the same configuration as in Example 1 was used, in which a piezoelectric element having a resin diaphragm was used as the vibrator. In Comparative Example 1, similar to the configuration shown in FIG. 3(a), the entire surface of the vibrator including the piezoelectric element was fixed to the vibrating body by double-sided tape. For the measurement, the input voltage was 12 Vpp, and the microphone distance was 10 cm.

[0050] 5 is a diagram showing the results of an evaluation test of the output sound pressure of the vibration device. As shown in the figure, in the frequency band of 100 Hz to 1000 Hz, the output sound pressure of the vibration devices of Examples 1 and 2 was improved by up to about 20 dB compared to the vibration device of the comparative example. From this result, it was confirmed that a configuration, as disclosed herein, in which the deformation tolerance of the vibrator and vibrating body due to the second fixing part is greater than the deformation tolerance of the vibrator and vibrating body due to the first fixing part contributes to the output of long-wavelength vibrations while avoiding vibration transmission loss between the piezoelectric element and the vibrating body.

[0051] The gist of the present disclosure is as follows: [1] to

[11] . [1] A vibration device comprising: a vibrator including a piezoelectric element; and a vibrating body fixed so as to overlap the vibrator via a fixing portion, wherein the fixing portion has a first fixing portion located toward the center in a plan view of the vibrator and the vibrating body, and a second fixing portion located outside the first fixing portion, and the deformation tolerance of the vibrator and the vibrating body due to the second fixing portion is greater than the deformation tolerance of the vibrator and the vibrating body due to the first fixing portion. [2] The vibration device according to [1], wherein the second fixed portion is spaced apart from the first fixed portion. [3] The vibration device according to [1] or [2], wherein the second fixing portions are arranged in a pair on either side of the first fixing portion. [4] The vibration device according to any one of [1] to [3], wherein the second fixing portion is arranged so as to overlap an edge of the vibrator. [5] The vibration device according to any one of [1] to [4], wherein the second fixing portion is disposed so as to protrude outward beyond the edge of the vibrator. [6] A vibration device as described in [5], wherein the area of ​​the region of the second fixing portion located outside the edge of the vibrator is larger than the area of ​​the region located inside the edge of the vibrator. [7] The vibration device according to any one of [1] to [6], wherein the first fixing portion is located apart from the edge of the vibrator and inside the edge of the vibrator. [8] The vibration device according to any one of [1] to [7], wherein the thickness of the first fixing portion and the thickness of the second fixing portion are equal to each other. [9] The vibration device according to any one of [1] to [8], wherein the facing area between the first fixing portion and the vibrator is larger than the facing area between the second fixing portion and the vibrator.

[10] A vibration device described in any one of [1] to [9], wherein the first fixing portion is made of double-sided tape, and the second fixing portion is made of a sponge and double-sided tape provided on both sides of the sponge.

[11] The vibration device according to any one of [1] to

[10] , wherein a weight member is fixed to the vibrator with its center aligned with the first fixing portion. [Explanation of symbols]

[0052] 1...vibration device, 2...vibrator, 3...piezoelectric element, 4...vibrating body, 5...fixed portion, 5A...first fixed portion, 5B...second fixed portion, 6...double-sided tape, 7...sponge, 8...double-sided tape, 9...weight member.

Claims

1. A vibrator including a piezoelectric element; a vibrator fixed to the vibrator via a fixing portion so as to overlap the vibrator; the fixing portion has a first fixing portion located on a central side in a plan view of the vibrator and the vibrating body, and a second fixing portion located outside the first fixing portion, A vibration device, wherein the deformation tolerance of the vibrator and the vibrating body due to the second fixing portion is greater than the deformation tolerance of the vibrator and the vibrating body due to the first fixing portion.

2. The vibration device according to claim 1 , wherein the second fixed portion is spaced apart from the first fixed portion.

3. The vibration device according to claim 1 , wherein the second fixing portions are arranged in a pair on either side of the first fixing portion.

4. The vibration device according to claim 1 , wherein the second fixing portion is arranged to overlap an edge of the vibrator.

5. The vibration device according to claim 1 , wherein the second fixing portion is disposed so as to protrude outward beyond an edge of the vibrator.

6. The vibration device according to claim 5 , wherein an area of ​​the second fixing portion that is located outside the edge of the vibrator is larger than an area of ​​the second fixing portion that is located inside the edge of the vibrator.

7. The vibration device according to claim 1 , wherein the first fixing portion is spaced apart from an edge of the vibrator and positioned inside the edge of the vibrator.

8. The vibration device according to claim 1 , wherein the first fixing portion and the second fixing portion have an equal thickness.

9. The vibration device according to claim 1 , wherein a facing area between the first fixed portion and the vibrator is larger than a facing area between the second fixed portion and the vibrator.

10. the first fixing portion is formed of a double-sided tape, The vibration device according to claim 1 , wherein the second fixing portion is constituted by a sponge and double-sided tape provided on both sides of the sponge.

11. The vibration device according to claim 1 , wherein a weight member is fixed to the vibrator with its center aligned with the first fixed portion.

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