JP2016103773A - Sound generator and electronic apparatus using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin sound generator that generates a sound with a high sound pressure at a low frequency.SOLUTION: There is provided a sound generator, including: a tabular first component 11 that has a principal surface 11a and a principal surface 11b facing each other, and has a through hole 16 that penetrates from the principal surface 11a through the principal surface 11b; a tabular second component 12 that has a principal surface 12a and a principal surface 12b facing each other, and is arranged inside the through hole 16; piezoelectric elements (15a and 15b) that are provided on at least one of the principal surface 12a and principal surface 12b of the second component 12; a third component 13 that entirely connects the peripheral part of the through hole 16 on the principal surface 11a of the first component 11 and the peripheral part on the principal surface 12a of the second component 12; and a plurality of fourth components (14a, 14b, 14c, and 14d) that partially connects the peripheral part of the through hole 16 on the principal surface 11b of the first component 11 and the peripheral part on the principal surface 12b of the second component 12.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an acoustic generator and an electronic device using the same.

  Conventionally, a speaker in which a piezoelectric element is attached to a diaphragm is known (for example, see Patent Document 1).

Japanese Patent Laid-Open No. 2004-23436

  However, the above-described conventional speaker has a problem that it is difficult to increase the sound pressure particularly in a low frequency region. In addition, as a conventional sound generator that generates low-frequency sound, a super woofer including a large electromagnetic speaker and a large resonance box is known, but it is difficult to downsize (particularly thin). was there.

  The present invention has been devised in view of such problems in the prior art, and an object of the present invention is to provide a thin acoustic generator capable of generating sound with a high sound pressure at a low frequency, and the same. It is to provide an electronic device used.

  The acoustic generator according to the present invention has a first main surface and a second main surface facing each other, and has a through hole penetrating from the first main surface to the second main surface. A first part, a plate-like second part having a first main surface and a second main surface facing each other and disposed inside the through hole, and the first main surface of the second part And a piezoelectric element provided on at least one of the second main surface, a peripheral portion of the through hole in the first main surface of the first component, and a peripheral portion of the first main surface of the second component A third part, a peripheral part of the through hole in the second main surface of the first part, and a peripheral part of the second main surface of the second part. And a plurality of fourth parts connected to.

  The electronic device of the present invention includes at least one speaker, a support body to which the speaker is attached, and an electronic circuit connected to the speaker, and the speaker is configured using the acoustic generator. It is characterized by being.

  The sound generator of the present invention is thin and can generate sound with high sound pressure at a low frequency. The electronic device of the present invention can generate sound with high sound pressure at a low frequency.

It is a perspective view showing typically the sound generator of a 1st embodiment of the present invention. It is the sectional view on the AB line in FIG. It is a top view showing typically the sound generator of a 1st embodiment of the present invention. It is a figure which shows the structure of the electronic device of 2nd Embodiment of this invention. It is a graph which shows the frequency characteristic of the sound pressure of the sound which the sound generator of 1st Embodiment of this invention generate | occur | produces.

  Hereinafter, an acoustic generator and an electronic apparatus using the same according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

(First embodiment)
FIG. 1 is a perspective view schematically showing a sound generator according to a first embodiment of the present invention. 2 is a cross-sectional view taken along line AB in FIG. In order to facilitate understanding of the structure, FIG. 2 shows an enlarged view in the thickness direction of the sound generator (+ z direction in the figure). As shown in FIGS. 1 to 3, the acoustic generator of this example includes a first component 11, a second component 12, a third component 13, a fourth component (14 a, 14 b, 14 c, 14 d), have.

  The first component 11 has a plate shape, and has a main surface 11a and a main surface 11b facing each other. Moreover, the 1st component 11 has the through-hole 16 penetrated from the main surface 11a to the main surface 11b. The material of the first component 11 is not particularly limited, and various materials such as a metal material, a plastic material, and wood can be used, but it is preferable that the first component 11 has higher rigidity than the second component 12, for example, Stainless steel can be suitably used. The thickness of the first component 11 can be, for example, about 0.5 mm to 2 mm. The outer shape of the first component 11 is not limited to a rectangle, but may be another polygonal shape, or may be a circle or an ellipse. The planar shape of the through-hole 16 is not particularly limited, but is desirably similar to the second component 12.

  The second component 12 has a plate-like shape and has a main surface 12a and a main surface 12b facing each other. The main surface 12a is located on the −z direction side, and the main surface 12b is located on the + z direction side. The second component 12 has a shape smaller than the through hole 16 and is disposed inside the through hole 16. The material of the second component 12 is not particularly limited, and various materials such as a metal material, a plastic material, and wood can be used. However, since the material is preferably light and strong, for example, aluminum or magnesium. And alloys thereof can be preferably used. The thickness of the second component 12 can be, for example, about 0.05 mm to 0.5 mm. The external shape of the second component 12 is not limited to a circular shape, and may be an elliptical shape or a polygonal shape in some cases. The space | interval of the 1st component 11 and the 2nd component 12 can be about 1 mm-5 mm, for example.

  The third component 13 has a flat shape such as a film shape or a plate shape, and has an annular plane shape. The third component 13 has an annular main surface 13a, and the outer peripheral edge of the main surface 13a is joined to the peripheral edge of the through hole 16 in the main surface 11a of the first component 11 as a whole. In addition, the inner peripheral edge of the main surface 13 a is entirely joined to the peripheral edge of the main surface 12 a of the second component 12. In this way, the third component 13 generally connects the peripheral portion of the through hole 16 in the main surface 11 a of the first component 11 and the peripheral portion of the main surface 12 a of the second component 12. For joining the first component 11 and the second component 12 to the third component 13, various known joining members such as various adhesives can be used.

It is desirable that the third component 13 is light, easily deformed, and strong. For this reason, the third part 13 is more easily deformed than the material constituting the first part 11 and the second part 12, that is, the material constituting the first part 11 and the material constituting the second part 12. A material having a small elastic modulus is used. As a material of the third component 13, for example, a resin material such as a silicone resin, or a rubber material such as urethane rubber, silicone rubber, or acrylic rubber can be used. In particular, porous rubber (foam rubber) formed using a rubber material such as urethane rubber, silicone rubber, polyethylene rubber, or the like can be suitably used. Among these, a silicone foam can be particularly preferably used. Moreover, the thickness of the 3rd component 13 can be about 0.1 mm-1 mm, for example.

  Each of the fourth parts (14a, 14b, 14c, 14d) has a long shape in one direction, and one longitudinal end of each of the fourth parts (14a, 14b, 14c, 14d) is the first. It is joined to one part 11, and the other end in the longitudinal direction of each of the fourth parts (14 a, 14 b, 14 c, 14 d) is joined to the second part 12. In this way, the fourth component (14a, 14b, 14c, 14d) includes the peripheral portion of the through hole 16 in the main surface 11b of the first component 11 and the peripheral portion of the main surface 12b of the second component 12. Partially connected. For joining the first part 11 and the second part 12 to the fourth part (14a, 14b, 14c, 14d), various known joining members such as various adhesives can be used.

  Further, when viewed in plan from the + z direction, the fourth component 14 a is disposed on the −x direction side with respect to the center of gravity 12 c of the second component 12, and the fourth component 14 b is the center of gravity 12 c of the second component 12. The fourth component 14c is disposed on the −y direction side with respect to the center of gravity 12c of the second component 12, and the fourth component 14d is disposed on the center of gravity of the second component 12. It is arranged on the + y direction side with respect to 12c. That is, when viewed in plan from the + z direction, the fourth component 14a and the fourth component 14b are arranged so as to face each other with the center of gravity 12c of the second component 12 therebetween, and the fourth component 14c and the fourth component 14d is arrange | positioned so that it may oppose on both sides of the gravity center 12c of the 2nd component 12. Then, when viewed in plan from the + z direction, a straight line connecting the fourth component 14a and the fourth component 14b and a straight line connecting the fourth component 14c and the fourth component 14d intersect each other (specifically, they are orthogonal to each other). As described above, the fourth parts (14a, 14b, 14c, 14d) are arranged. In addition, in this specification, when planarly viewing, it shall planarly view from + z direction side.

  The fourth parts (14a, 14b, 14c, 14d) are desirably light, moderately elastic, and strong. Therefore, the fourth parts (14a, 14b, 14c, 14d) are materials having a smaller elastic modulus than the material constituting the first part 11 and the material constituting the second part 12, and the third part 13 It is comprised using the material which has the same or large elasticity modulus compared with the material to comprise. As a material of the fourth component (14a, 14b, 14c, 14d), for example, a resin material such as polyethylene, polyimide, polypropylene, or polystyrene, or a rubber material such as urethane rubber, silicone rubber, or acrylic rubber can be used. Porous rubber (foamed rubber) formed using a rubber material such as urethane rubber, silicone rubber, polyethylene rubber or the like can also be used, and a silicone foam can be suitably used. Moreover, the thickness of the fourth component (14a, 14b, 14c, 14d) can be, for example, about 0.1 mm to 1 mm. Note that the number of the fourth parts may be at least two or more, and may be more than four.

  A piezoelectric element 15 a is attached to the center of the main surface 12 a of the second component 12, and a piezoelectric element 15 b is attached to the center of the main surface 12 b of the second component 12. The piezoelectric elements (15a, 15b) have a rectangular flat plate shape in which the length direction is the + x direction, the width direction is the + y direction, and the thickness direction is the + z direction. Although not shown in detail, the piezoelectric elements (15a, 15b) are composed of a laminate, a plurality of surface electrodes, and a plurality of side electrodes. The laminate is configured by alternately laminating piezoelectric layers made of piezoelectric ceramics and internal electrode layers in the + z direction. The plurality of surface electrodes are respectively disposed on the two main surfaces of the laminate. The plurality of side electrodes are respectively provided on the surface in the length direction of the multilayer body. In addition, the surface electrode and the internal electrode layer are alternately drawn out to the surface in the length direction of the multilayer body, and are connected to the side electrodes, respectively. The piezoelectric layers and various electrodes constituting the piezoelectric elements (15a, 15b) can be configured using known materials.

  The piezoelectric elements (15a, 15b) are configured such that expansion and contraction are reversed in the + z direction and the -z direction at an arbitrary moment when an electric signal is input. Therefore, the piezoelectric elements (15a, 15b) bend and vibrate when an electric signal is input. And the piezoelectric element (15a, 15b) and the 2nd component 12 are adhere | attached, for example with known adhesive agents, such as an epoxy resin, a silicon resin, and a polyester resin, a double-sided tape. Note that the piezoelectric elements (15a, 15b) may be unimorph type vibration elements configured by bonding a piezoelectric element that receives an electric signal to undergo stretching vibration and a metal plate. In addition, the piezoelectric elements (15a, 15b) may be piezoelectric elements that expand and contract by receiving electric signals. In that case, when one of the piezoelectric element 15a and the piezoelectric element 15b expands, the other should contract. Further, the piezoelectric element may be attached only to one main surface of the second component 12.

  In the acoustic generator of this example having such a configuration, when an electric signal is input and the piezoelectric elements (15a, 15b) vibrate, the second component 12 vibrates, and the second component 12 vibrates. Occur.

  The sound generator of this example includes a first component 11, a second component 12, a third component 13, and a fourth component (14a, 14b, 14c, 14d). The first component 11 has a plate shape, and has a main surface 11a and a main surface 11b facing each other. Moreover, the 1st component 11 has the through-hole 16 penetrated from the main surface 11a to the main surface 11b. The second component 12 has a plate shape and is disposed inside the through hole 16. The second component 12 has a main surface 12a and a main surface 12b facing each other. The piezoelectric elements (15a, 15b) are provided on the main surface 12a and the main surface 12b of the second component 12 (the piezoelectric elements may be provided on at least one of the main surface 12a and the main surface 12b). The third component 13 generally connects the peripheral portion of the through hole 16 in the main surface 11 a of the first component 11 and the peripheral portion of the main surface 12 a of the second component 12. The fourth component (14a, 14b, 14c, 14d) partially connects the peripheral edge of the through hole 16 in the main surface 11b of the first component 11 and the peripheral edge of the main surface 12b of the second component 12. . With such a configuration, vibration that causes the first component 11 to be displaced in the + z direction and the −z direction as a whole also occurs, so that it is possible to generate sound with high sound pressure at a low frequency. Further, the fourth component (14a, 14b, 14c, 14d) can suppress the horizontal vibration of the second component 12 without significantly disturbing the overall vibration of the second component 12 in the z-axis direction. Therefore, it is possible to generate sound with high sound pressure and low sound quality at a low frequency. Moreover, a thin sound generator can be obtained by such a structure.

  In the acoustic generator of this example, the third component 13 has an annular main surface 13 a, and the outer peripheral edge of the main surface 13 a of the third component 13 is the main surface 11 a of the first component 11. The inner peripheral edge portion of the main surface 13a of the third component 13 is generally bonded to the peripheral edge portion of the main surface 12a of the second component 12. ing. As a result, it is possible to generate a sound having a high sound pressure at a low frequency by virtue of the overall vibration of the second component 12 in the z-axis direction without disturbing the bending vibration of the second component 12. Note that this configuration is not essential, and in some cases, this configuration may not be provided.

  In the acoustic generator of this example, the third component 13 is configured using a material having a smaller elastic modulus than the material configuring the first component 11 and the material configuring the second component 12. Thereby, the second component 12 can be vibrated greatly in the z-axis direction. Note that this configuration is not essential, and in some cases, this configuration may not be provided.

In the acoustic generator of this example, each of the fourth parts (14a, 14b, 14c, 14d) has a long shape in one direction, and each of the fourth parts (14a, 14b, 14c,
14d) one end in the longitudinal direction is joined to the first part 11, and the other end in the longitudinal direction of each fourth part (14a, 14b, 14c, 14d) is joined to the second part 12. Thereby, the hindrance of the vibration of the 2nd component 12 in the whole z-axis direction can further be reduced. Note that this configuration is not essential, and in some cases, this configuration may not be provided.

  In addition, the acoustic generator of this example includes two fourth components (fourth component 14a and fourth component 14b) arranged so as to face each other with the center of gravity 12c of the second component 12 therebetween when viewed in plan. Have. Thereby, the vibration of the 2nd component 12 of the direction (x-axis direction) which ties the 4th component 14a and the 4th component 14b can be suppressed effectively. In addition, the acoustic generator of this example includes two fourth parts (fourth part 14c and fourth part 14d) arranged so as to face each other with the center of gravity 12c of the second part 12 therebetween when viewed in plan. Have. Thereby, the vibration of the 2nd component 12 of the direction (y-axis direction) which ties the 4th component 14c and the 4th component 14d can be suppressed effectively. Note that this configuration is not essential, and in some cases, this configuration may not be provided.

  In addition, the acoustic generator of this example has two sets of two fourth parts arranged so as to face each other with the center of gravity 12c of the second part 12 therebetween when viewed in plan. When viewed from above, a straight line connecting two fourth parts (fourth part 14a and fourth part 14b) constituting one set and two fourth parts (fourth part 14c) constituting the other set And the 4th parts (14a, 14b, 14c, 14d) are arrange | positioned so that the straight line which ties the 4th parts 14d) may mutually cross. Thereby, the vibration of the direction in the xy plane of the 2nd component 12 can be suppressed effectively. It should be noted that the four parts 14a and the fourth part 14b are connected so that the direction connecting the fourth part 14a and the fourth part 14b (x-axis direction) and the direction connecting the fourth part 14c and the fourth part 14d (y-axis direction) are orthogonal to each other. By arranging the four parts (14a, 14b, 14c, 14d), it is possible to more effectively suppress the vibration of the second part 12 in the xy plane. If the angle formed by the direction connecting the fourth component 14a and the fourth component 14b (x-axis direction) and the direction connecting the fourth component 14c and the fourth component 14d is about 87 ° to 93 °, The direction connecting the fourth component 14a and the fourth component 14b (x-axis direction) and the direction connecting the fourth component 14c and the fourth component 14d can be considered to be orthogonal. Note that this configuration is not essential, and in some cases, this configuration may not be provided.

  In the acoustic generator of the present example, the fourth parts (14a, 14b, 14c, 14d) have a smaller elastic modulus than the material constituting the first part 11 and the material constituting the second part 12, and the third part In the case of using a material having a higher elastic modulus than the material constituting the part 13, the second part 12 is reduced while preventing the overall vibration of the second part 12 in the z-axis direction. Twelve horizontal vibrations can be effectively suppressed. Note that this configuration is not essential, and in some cases, this configuration may not be provided.

  Further, in the acoustic generator of this example, the peripheral edge of the first component 11 is fixed to another object, and an electric signal is input to the piezoelectric elements (15a, 15b), whereby the first component 11 and the second component 12 are input. When both are vibrated and sound is generated from both the first component 11 and the second component 12, the overall sound pressure can be further increased. Note that this configuration is not essential, and in some cases, this configuration may not be provided.

  The sound generator of this embodiment can be manufactured as follows, for example. First, a binder, a dispersant, a plasticizer, and a solvent are added to the powder of the piezoelectric material and stirred to prepare a slurry. As the piezoelectric material, any of lead-based and non-lead-based materials can be used. Next, the obtained slurry is formed into a sheet shape to produce a green sheet. A conductor paste is printed on the green sheet to form a conductor pattern to be an internal electrode, and the green sheet on which the conductor pattern is formed is laminated to produce a laminated molded body.

  Next, this laminated molded body is degreased, fired, and cut into a predetermined size to obtain a laminated body. And the outer peripheral part of a laminated body is processed as needed. Next, the conductor paste is printed on the main surface in the stacking direction of the multilayer body to form a conductor pattern to be a surface electrode, and the conductor paste is printed on both side surfaces in the length direction of the multilayer body to be side electrodes. A conductor pattern is formed. And the structure used as a piezoelectric element (15a, 15b) can be obtained by baking an electrode at predetermined temperature. Thereafter, in order to impart piezoelectricity to the piezoelectric elements (15a, 15b), a DC voltage is applied through the surface electrodes or the side electrodes to polarize the piezoelectric layers of the piezoelectric elements (15a, 15b). In this way, the piezoelectric elements (15a, 15b) can be obtained.

  Next, the first part 11, the second part 12, the third part 13 and the fourth part (14a, 14b, 14c, 14d) processed into a predetermined shape are prepared, and together with the piezoelectric elements (15a, 15b) Join the joint with an adhesive or the like. In this way, the sound generator of this embodiment can be obtained.

(Second Embodiment)
FIG. 4 is a diagram illustrating a configuration of an electronic device 50 according to the second embodiment of the present invention. As shown in FIG. 4, the electronic device 50 of this example includes a speaker 30, a housing 40, an electronic circuit 60, a key input unit 50c, a microphone input unit 50d, a display unit 50e, and an antenna 50f. Have.

  The electronic circuit 60 includes a control circuit 50a and a communication circuit 50b. The electronic circuit 60 is connected to the speaker 30 and has a function of outputting an audio signal to the speaker. The control circuit 50 a is a control unit of the electronic device 50. The communication circuit 50b transmits and receives data through the antenna 50f based on the control of the control circuit 50a.

  The key input unit 50c is an input device of the electronic device 50 and accepts a key input operation by an operator. The microphone input unit 50d is also an input device of the electronic device 50, and accepts a voice input operation by an operator. The display unit 50e is a display output device of the electronic device 50, and outputs display information based on the control of the control circuit 50a.

  The speaker 30 is configured by the sound generator of the present invention as in the first embodiment described above. The speaker 30 functions as a sound output device in the electronic device 50, and generates sound (including sound outside the audible frequency band) based on the sound signal input from the electronic circuit 60. Note that the speaker 30 is connected to the control circuit 50a of the electronic circuit 60, and generates a sound upon application of a voltage controlled by the control circuit 50a.

  The housing 40 has a function of accommodating and protecting the electronic circuit 60 and the like. The speaker 30, the key input unit 50c, the microphone input unit 50d, the display unit 50e, and the antenna 50f are attached and fixed to the housing 40. The housing 40 includes the speaker 30, the key input unit 50c, and the microphone input unit. 50d, functioning as a support member that supports the display unit 50e and the antenna 50f. In FIG. 4, the speaker 30, the electronic circuit 60, the key input unit 50 c, the microphone input unit 50 d, and the display unit 50 e are housed in the housing 40, but the present invention is not limited to this. It is not a thing. The speaker 30, the electronic circuit 60, the key input unit 50c, the microphone input unit 50d, the display unit 50e, and the like may be exposed on the surface of the electronic device 50. Such a casing 40 can be formed using various materials having rigidity sufficient to support the speaker 30 and the like, and can be formed using materials such as wood, synthetic resin, and metal, for example. .

Since the electronic device 50 of this example generates sound using the speaker 30 configured by the sound generator as in the first embodiment described above, it can generate sound with high sound pressure at a low frequency. .

  The electronic device 50 only needs to include at least the speaker 30, a support body that supports the speaker 30, and the electronic circuit 60. The electronic device 50 does not have to include all of the speaker 30, the casing 40, the electronic circuit 60, the key input unit 50c, the microphone input unit 50d, the display unit 50e, and the antenna 50f. Other components may be included. The electronic circuit 60 is not limited to the electronic circuit 60 having the above-described configuration, and may be an electronic circuit having another configuration.

  Further, the electronic device on which the speaker 30 is mounted is not limited to a mobile terminal such as a mobile phone or a tablet terminal. In various electronic devices having a function of generating sound, the speaker 30 using the sound generator as in the first embodiment described above can be used as a sound generator. For example, in flat-screen TVs and car audio devices, of course, in the electronic devices such as vacuum cleaners, washing machines, refrigerators, and microwave ovens having a function of generating sound and sound, sound generation as in the first embodiment described above is possible. The speaker 30 composed of a container can be used as a sound generator.

  Next, a specific example of the sound generator of the present invention will be described. The acoustic generator according to the first embodiment of the present invention shown in FIGS. 1 to 3 was produced and its performance was evaluated.

  The piezoelectric elements (15a, 15b) were piezoelectric elements in which a PZT-based piezoelectric layer and an electrode layer were laminated. The shape of the piezoelectric elements (15a, 15b) was a plate shape having a length of 55 mm, a width of 45 mm, and a thickness of 0.15 mm. The first component 11 was formed using stainless steel and was plate-shaped having a length of 190 mm, a width of 190 mm, and a thickness of 1 mm. In addition, a circular through hole 16 having a diameter of 160 mm was formed in the center of the first component 11. The second part 12 was formed using aluminum and formed into a disk shape having a diameter of 150 mm and a thickness of 0.3 mm. The third component 13 was formed using a silicon foam, and had an annular shape with a thickness of 0.5 mm. The fourth part (14a, 14b, 14c, 14d) was formed using a silicon foam and was a rectangular parallelepiped having a length of 4 mm, a width of 1.5 mm, and a thickness of 0.5 mm.

  The characteristics of the produced sound generator are shown in FIG. FIG. 5 is a graph showing a change in sound pressure depending on the frequency of sound generated from the sound generator, and is 1 m away from the sound generator when a sine wave having an effective value of 7.5 V is given to the sound generator. It shows the sound pressure of the place. In the graph shown in FIG. 5, the horizontal axis indicates the frequency, and the vertical axis indicates the sound pressure level. In the measurement, a baffle board for preventing sound from wrapping around from the back surface of the sound generator was attached to the periphery of the first component 11 and measured.

  According to the graph shown in FIG. 5, a high sound pressure of about 80 dB is obtained in a low frequency range of about 100 Hz, and the change in sound pressure is small in the range of 100 Hz to 500 Hz. It can be seen that sound is generated. This result confirms the effectiveness of the present invention.

11: 1st part 12: 2nd part 13: 3rd parts 14a, 14b, 14c, 14d: 4th parts 11a, 12a, 13a: 1st main surface 11b, 12b: 2nd main surface 12c: Center of gravity 15a, 15b : Piezoelectric element 16: Through hole 30: Sound generator 50: Electronic device 60: Electronic circuit

Claims (9)

A plate-like first component having a first main surface and a second main surface facing each other, and having a through-hole penetrating from the first main surface to the second main surface;
A plate-like second component having a first main surface and a second main surface facing each other and disposed inside the through hole;
A piezoelectric element provided on at least one of the first main surface and the second main surface of the second component;
A third component that generally connects a peripheral portion of the through hole in the first main surface of the first component and a peripheral portion of the first main surface of the second component;
A plurality of fourth components that partially connect the peripheral edge of the through hole in the second main surface of the first component and the peripheral edge of the second main surface of the second component;
A sound generator characterized by comprising: The third part has an annular first main surface;
The outer peripheral edge of the first main surface of the third component is entirely joined to the peripheral edge of the through hole in the first main surface of the first component,
The inner peripheral edge portion of the third component on the first main surface is entirely joined to the peripheral edge portion of the second component on the first main surface.
The sound generator according to claim 1.   3. The third part according to claim 1, wherein the third part is made of a material having a smaller elastic modulus than a material constituting the first part and a material constituting the second part. The described sound generator.   The fourth part is made of a material having a smaller elastic modulus than a material constituting the first part and a material constituting the second part and having a larger elastic modulus than a material constituting the third part. The sound generator according to claim 3, wherein the sound generator is provided.   The fourth component has a long shape in one direction, one end in the longitudinal direction of the fourth component is joined to the first component, and the other end in the longitudinal direction of the fourth component is The sound generator according to any one of claims 1 to 4, wherein the sound generator is joined to the second component.   6. The sound generation according to claim 1, comprising two of the fourth parts disposed so as to face each other with a center of gravity of the second part interposed therebetween when viewed in a plan view. vessel. Having two sets of two fourth parts arranged so as to face each other with the center of gravity of the second part in between when viewed in plan,
When viewed in plan, four lines are formed so that a straight line connecting the two fourth parts constituting one of the sets and a straight line connecting the two fourth parts constituting the other set intersect each other. The sound generator according to claim 1, wherein the fourth component is arranged.   When the peripheral edge of the first part is fixed to another object and an electric signal is input to the piezoelectric element, both the first part and the second part vibrate, and the first part and the first part are vibrated. The sound generator according to any one of claims 1 to 7, wherein sound is generated from both of the two parts.   The sound generator according to claim 1, comprising at least one speaker, a support body to which the speaker is attached, and an electronic circuit connected to the speaker. An electronic device characterized by being configured using a container.