JP2022129647A - Acoustic device and electronic device - Google Patents

Abstract

To provide an acoustic device and an electronic device capable of preventing reduction of functions on generation and/or detection of sound while having a waterproof function.SOLUTION: An acoustic device includes a sound transmitting portion (13) having a vibrating membrane (131) having waterproof property, a support member (133) located in line in an X direction with the vibrating membrane (131) and having a small hole (133a), and an adhesive tape (132) located between the vibrating membrane (131) and the support member (133) and having an aperture (132a) in a range including the small hole (133a). The small hole (133a) is located within a range encompassed by the aperture (132a) in a plan view along the X direction in a state where the sound transmitting portion (13) is pressed with reference pressure in the X direction.SELECTED DRAWING: Figure 3

Description

The present invention relates to acoustic devices and electronic equipment.

Portable and wearable electronic devices are used in various environments. If this electronic device is to be used underwater, it must be waterproof and pressure resistant.

In Patent Document 1, when the key sheet of the mobile terminal is excessively pressed by a finger or the like, the adhesive member that adheres the waterproof film protrudes from the adhesion range and adheres to other parts, causing an irreversible inconvenience. In order to suppress this, a technology is disclosed in which a convex portion is provided on the back side of the key sheet to prevent it from being pushed too much.

JP 2013-207576 A

However, in an acoustic device that generates and/or detects sound, in order to have a waterproof function, the waterproof membrane needs to vibrate in order to transmit sound across the waterproof membrane. Therefore, there is a problem that the acoustic device cannot have a configuration that prevents this vibration.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an acoustic device and an electronic device capable of suppressing deterioration of functions related to sound generation and/or detection while having a waterproof function.

In order to achieve the above object, the present invention
a waterproof vibrating membrane;
a support member positioned side by side with the vibrating membrane in a certain direction and having a through hole;
an adhesive layer positioned between the vibrating membrane and the support member and having an opening in a range including the through hole;
comprising an acoustic transmission unit having
The through-hole is positioned within a range encompassed by the opening in plan view along the certain direction in a state in which the sound transmission portion is pressed in the certain direction by a predetermined force. It is a sound device that features.

ADVANTAGE OF THE INVENTION According to this invention, it is an acoustic apparatus.

FIG. 3 is a partial cross-sectional view showing the vicinity of the acoustic device of the electronic device of the present embodiment; It is a figure explaining an acoustic transmission part. It is a figure explaining the positional relationship of an adhesive tape and a support member.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a partial cross-sectional view showing the vicinity of an acoustic device 10 of an electronic device 1 of this embodiment.
The electronic device 1 is, for example, an electronic wristwatch, and includes a housing 20, a windshield 30, a back cover 40, a display screen 50, an operating section 60, an audio device 10, and the like.

The housing 20 is a cylindrical member that is open at the top and bottom. The upper surface side where the display screen 50 is located is covered with a windshield 30, and the lower surface side is covered with a back cover 40. is sealed inside.

The windshield 30 is a transparent member such as glass. The back cover 40 is a conductive member. The housing 20 is a dielectric such as resin here.

The display screen 50 is, for example, a liquid crystal display screen, and the display contents can be visually recognized from the outside through the windshield 30 . The operation unit 60 has a CPU, a RAM, and the like, and controls various operations of the electronic device 1 . A battery and the like are also accommodated in the space sealed by the housing 20, the windshield 30, and the back cover 40. As shown in FIG.

The electronic device 1 may have an exterior member such as a bezel on the outside of the housing 20 . The exterior member can be used for mitigating impact from the outside and as a decoration.

The acoustic device 10 is a device that outputs or detects sound (sound waves), that is, a speaker or a microphone.

The acoustic device 10 includes a sound converting portion 11 (acoustic module), a rubber edge 12, a sound transmitting portion 13, a waterproof packing 14, a sound hole case 15, a compression plate 16, a dustproof plate 17, and screws 18. , an exterior member 19, and the like.

The housing 20 has a recess 201 on the outside and a recess 202 on the inside. The acoustic converter 11 and the rubber edge 12 of the acoustic device 10 are located in the recess 202 of the housing 20 , and the acoustic transmitter 13 and the waterproof packing 14 are housed in the recess 201 . The recesses 201 and 202 communicate with each other through an air passage 203 . The air passage 203 may be bent in the middle.

The acoustic converter 11 is a speaker element or a microphone element (collectively referred to as a conversion element) that converts between voice (sound wave) and electric signal. A rubber edge 12 is positioned around the transducer element of the acoustic transducer 11 .

Although the detailed configuration of the acoustic transmission section 13 will be described later, it has a vibrating membrane 131 . The vibrating membrane 131 is a conventionally known thin film member that vibrates in response to sound waves and transmits sound from one side to the other with the vibrating membrane 131 sandwiched therebetween. Also, the vibrating membrane 131 is waterproof. In other words, the vibrating membrane 131 does not allow water to pass therethrough under water pressure within the reference range, and does not break or irreversibly deform. Thereby, the vibrating film 131 prevents water from entering the air passage 203 and the sound conversion section 11 from the outside.

The waterproof packing 14 is an O-ring annularly positioned along the periphery of the sound transmission portion 13 . The waterproof packing 14 has a shape corresponding to the outer peripheral shape of the sound transmission portion 13 and is slightly larger than the sound transmission portion 13 . The waterproof packing 14 is pressed from the outside against the peripheral edge of the sound transmission part 13 and the recess 201 on the outer side thereof, thereby preventing water from entering the interior through the gap at the peripheral edge of the sound transmission part 13 .

The sound hole case 15 is a resin case having an air passage 151 passing through the center. The inner side (on the side of the waterproof packing 14) has an annular shape that is one step lower so that the waterproof packing 14 can be accommodated, and the outer side has a projecting portion 152 in the center through which the air passage 151 penetrates. A ring-shaped compression plate 16 is fitted around the projecting portion 152 . The sound hole case 15 is also a spacer member that separates the conductive dustproof plate 17 and the support member 133 of the sound transmission section 13 .

The compression plate 16 is a metal plate that presses and fixes the waterproof packing 14 by being fixed to the housing 20 with screws 18 . The compression plate 16 has through holes 161 . The protrusion 152 of the sound hole case 15 is inserted inside the through hole 161 . The compression plate 16 is larger than the sound hole case 15 in plan view, and is fixed by springs 18 at both ends thereof, so that the waterproof packing 14 can be uniformly pressed and fixed.

The dust-proof plate 17 has fine openings or meshes aligned with at least the positions of the air passages 151 . The dust-proof plate 17 is a metal plate such as stainless steel (SUS), and is fixed to the housing 20 with screws 18 together with the compression plate 16 . The openings or meshes allow sound to pass through while suppressing the intrusion of dirt and dust from the outside. The dust-proof plate 17 is electrically connected to the back cover 40 by the metal plate 41 and is grounded to the housing.

As described above, the screw 18 is a small screw that fixes the compression plate 16 and the dust-proof plate 17 to the housing 20 in a state that they are overlapped. The number of screws is not particularly limited, but is determined according to the size of the space and the certainty of fixation, and is, for example, two. The compression plate 16 is pressed and fixed by tightening the screw 18 strongly. In response to this pressing, the sound hole case 15 and the waterproof packing 14 are further pressed, and the waterproof packing 14 prevents water from entering the sound transmitting section 13 while pressing the sound transmitting section 13 . The screw 18 may be tightened with a strength according to the required waterproof performance (eg, 10-20 atmospheres).

The exterior member 19 is a cover member that covers the opening of the dustproof plate 17, and may have an appropriate shape according to the external design. The exterior member 19 is, for example, various resins.

FIG. 2 is a diagram for explaining the sound transmission unit 13. As shown in FIG.
The acoustic transmission unit 13 includes a vibrating membrane 131 that vibrates in response to acoustic vibration, and a direction perpendicular to one surface of the vibrating membrane 131 in a static state of silence under atmospheric pressure (a certain direction, defined as an X direction). supporting members 1331 and 1332 (together supporting members 133) positioned side by side on both sides (outer surface side and inner surface side) of the vibrating membrane 131; 1322 (adhesive layer, collectively adhesive tape 132). That is, the acoustic transmission section 13 is integrated with the support member 1332, the adhesive tape 1322, the vibration film 131, the adhesive tape 1321, and the support member 1331 in this order from the inside. The vibrating membrane 131 and the adhesive tape 132 may be one size smaller than the support member 133 . Note that the size of the vibrating membrane 131 does not have to be the same as the size of the adhesive tape 132 .

As described above, the vibrating membrane 131 transmits sound to the opposite side of the vibrating membrane 131 by vibrating in the air. Under water, the vibrating membrane 131 maintains waterproofness. In the following description, it is assumed that the vibrating membrane 131 is transparent, but it does not have to be transparent.

The support member 133 is a metal plate, and sandwiches and supports the vibrating membrane 131 from both sides. In addition, the support member 133 may not be a single member, and may be formed by integrating a plurality of members. The adhesive tape 132 adheres the diaphragm 131 and the support member 133 together. The adhesive tape 132 is a double-sided tape having adhesive member layers on both sides of a sheet-like base material. The adhesive member has elasticity at least within the assumed range of pressure, and is elastically deformed, ie, compressed, at a rate corresponding to the magnitude of the pressure. The thickness of the adhesive tape 132 in normal atmosphere is greater than or equal to the thickness at which the support member 133 does not hinder the vibration of the vibrating membrane 131 . The adhesive member may be cured and fixed by a predetermined energy such as heat.

FIG. 3 is a diagram for explaining the positional relationship between the adhesive tape 132 and the support member 133. As shown in FIG.
As shown in FIG. 3A, each of the support members 1331 (133) has, for example, a rectangular shape with rounded corners (both short sides). The small hole 133 a is positioned near the center of the support member 1331 .

FIG. 3(b) is a cross-sectional view cut along the cross-sectional line AA in FIG. 3(a).
The support member 133 has a plurality of small circular holes 133 a (through holes) with one end facing the air passage 151 or the air passage 203 and the other end opposite to the one end being connected to the vibrating membrane 131 . The supporting members 1331 and 1332 on both sides of the vibrating membrane 131 may have the small holes 133a at the same position when viewed from above in the X direction. Acoustic vibrations pass through this small hole 133a.

The adhesive tape 132 has openings 132a corresponding to areas including a plurality of small holes 133a of the support member 133 when seen from above. That is, the vibrating membrane 131 is not adhered by the adhesive tape 132 at the position corresponding to the small hole 133a. As a result, the adhesive tape 132 does not interfere with the acoustic vibration.

The opening 132a here is circular. Since the shape of the opening 132a is uniform without being anisotropic, when pressure is applied to the vibration film 131 in the X direction, there is no gap between the vibration film 131, the adhesive tape 132, and the support member 133. Stress tends to be even. The size of the opening 132a may be determined according to the frequency range of the sound transmitted by the vibrating membrane 131 (output or detected by the acoustic converter 11). In addition, the size of the opening 132a is set to be equal to or larger than the opening area of the air passage 203 (the cross-sectional area perpendicular to the extending direction), thereby reducing reverberations and muffled sounds due to unnecessary reflection near the vibrating membrane 131. . On the other hand, in the air passage 203, the end portion along the support member 1332 is expanded to the same size as the opening 132a.

FIG. 3(c) is a cross-sectional view cut along the cross-sectional line BB in FIG. 3(b).
The small holes 133a of the support member 133 are arranged near the center of the opening 132a of the adhesive tape 132 in plan view. The plurality of small holes 133a here are all circular, and are located at positions separated by a reference distance d from the edge of the opening 132a.

In water, the sound transmission part 13 is pressed by water pressure, and the pressure from the outside to the inside increases. As described above, since the inside is fixed by the housing 20, the acoustic transmission part 13 as a whole is compressed. In the sound transmitting portion 13, the thickness of the adhesive tape 132, which has the smallest elastic modulus and is thick, is mainly reduced. As a result, the adhesive tape 132 serves as a stress relieving layer that relieves stress applied to the vibrating film 131 and the like.

The adhesive member is not one-dimensionally compressed, but expands and bulges in a plane perpendicular to the pressing direction (X direction), that is, in a direction spreading along the adhesive surface of the adhesive tape 132 . The reference distance d is greater than the amount (deformation amount) by which the adhesive member (adhesive tape 132) expands when pressed by the reference pressure, which is not particularly limited, but is, for example, 20 atmospheres (predetermined force). largely defined. That is, all the small holes 133a are located within a range encompassed by the openings 132a in plan view along the X direction in a state of being pressed by the reference pressure in the X direction. Since the viscosity of the adhesive member also depends on the temperature, normal temperature (eg, 15 to 20° C.) or the upper limit of the operating temperature range of the electronic device 1 (eg, 80° C.) may be set as the reference temperature. In practice, even if the standard air pressure deviates slightly from the waterproof pressure, the adhesive member does not immediately have an irreversible fatal adverse effect. There is no problem even if the side is slightly larger) It may deviate from the waterproof pressure.

When the water pressure increases, the vibrating membrane 131 may come into contact with the support member 133 and further enter the inside of the small hole 133a. At this time, if the adhesive member protruding into the range of the opening 132a also enters the inside of the small hole 133a, it will not normally come out of the small hole 133a even after the pressure is released, and it will be difficult to return to its original position. Inhibits propagation. In particular, when the internal temperature of the electronic device 1 rises in such a state (for example, when left under direct sunlight), the adhesive member softens and plasticity is reduced, and irreversible change is likely to occur. By setting the reference distance d and narrowing the positional range of the small hole 133a compared to the opening 132a, it is possible to prevent the adhesive member from entering the small hole 133a together with the vibrating membrane 131. A deterioration in the function of the acoustic device 10 can be more reliably avoided. At this time, if the size of the area including the small hole 133a becomes too small, the sound quality will deteriorate, so the lower limit of this size can be determined according to the desired sound quality level.

As described above, the acoustic device 10 of the present embodiment includes the waterproof vibrating membrane 131, the support member 133 positioned side by side with the vibrating membrane 131 in the X direction and having the small hole 133a, and the vibrating membrane 131 and the supporting member. 133 and an adhesive tape 132 having an opening 132a in a range including the eyelet 133a. All the small holes 133a are in a state where the acoustic transmission part 13 is pressed in the X direction with a reference pressure (predetermined force) in the X direction, and the range is included in the opening 132a in plan view along the X direction. located within.
This can prevent the adhesive member of the adhesive tape 132 from entering the small hole 133a and not returning even when the vibrating membrane 131 comes into contact with the support member 133 due to high water pressure. Thereby, deterioration of the function of the acoustic device 10 can be reduced.

Further, the support member 133 has a plurality of small holes 133a. The edge of the opening 132a of the adhesive tape 132 is larger than the amount of deformation in the direction along the adhesive surface of the adhesive member when the acoustic transmission portion 13 is pressed with the reference pressure from the outer periphery of the range including all the small holes 133a. only a distance apart. As a result, the adhesive member can be prevented from entering any of the small holes 133a, and deterioration of the function of the acoustic device 10 can be more reliably reduced while maintaining the waterproof function.

Also, the opening 132a of the adhesive tape 132 is circular. As a result, even when a high pressure is applied, the pressure is uniformly applied to the movable portion of the vibrating film 131 regardless of the direction. Moreover, since the positional relationship of the small hole 133a with respect to the edge of the opening 132a is simplified, it is possible to compactly and efficiently suppress the penetration of the adhesive member into the small hole 133a.

In addition, the support member 133 is positioned closer to the inner surface of the acoustic transmission section 13 than the vibrating membrane 131 . In this case, the effect of reducing the contact between the adhesive member and the small hole 133a of the support member 133 on the side where the vibration film 131 contacts can be directly obtained by the above-described structure due to the high pressure.

Further, the support member 133 may be positioned closer to the outer surface of the sound transmission section 13 than the vibrating membrane 131 is. Even in this case, it is possible to prevent the adhesive member from irreversibly protruding and blocking the small hole 133a due to the vibration of the vibrating membrane 131 and the temperature rise of the acoustic device 10 or the like.

Also, the adhesive tape 132 is a double-sided tape. By bonding the vibrating membrane 131 and the support member 133 with double-sided tape, the bonding range can be determined more accurately. In addition, as a result, it is possible to reduce the size of the adhesive member protruding into the opening 132a.

Alternatively, the predetermined force may be approximately 20 atmospheres. If the pressure is several atmospheres, the adhesive member and the diaphragm 131 are not greatly affected by deformation. With the acoustic device 10 configured as described above, it is possible to suppress deterioration of the function of the acoustic device 10 due to troubles related to the adhesive member. In addition, by enabling this level of air pressure (water pressure), it becomes easier to perform work using water while the user is wearing it, so the usable range of the acoustic device 10 (electronic device 1) can be expanded.

The acoustic device 10 also includes an acoustic converter 11 that converts between sound waves and electrical signals, and an air passage 203 that connects the acoustic converter 11 and the acoustic transmitter 13 . The opening 132 a is larger than the opening area of the air passage 203 . As described above, the acoustic device 10 has a sufficiently large opening 132a compared to the air passage 203, so that it is possible to suppress muffled sound, reverberation, reduction in dynamic range, and the like.

Further, the electronic device 1 of this embodiment includes the acoustic device 10 described above.
As a result, adverse effects on the acoustic device 10 can be sufficiently reduced even when the electronic device 1 is used underwater.

It should be noted that the present invention is not limited to the above embodiments, and various modifications are possible.
For example, the support member 133 may have a larger through-hole rather than multiple small holes 133a, or may be a single through-hole.

Further, in the above embodiment, the diaphragm 131 is sandwiched between the support members 133 from both the inner and outer sides, but it may be adhered and fixed to only one side, for example, the outer support member 1331 . The other support member 1332 may be absent, or may be present but not adhered.

Moreover, the opening 132a of the adhesive tape 132 does not have to be circular. Similar to the outer shape, it may be rectangular with rounded corners (two opposing sides) or other shapes.

Further, the bonding between the vibrating membrane 131 and the support member 133 does not depend on the double-sided tape, and an adhesive that does not have a base material may be used.

Further, in the above-described embodiment, the 20-atmosphere water resistance has been described as an example, but the present invention is not limited to this. Even if it is waterproof to about 10 atmospheres, the structure shown in the above embodiment can provide more reliable waterproofness. Alternatively, it may have a waterproof function of 20 atmospheres or more, and for example, it may be used not only for life waterproofing, but also for equipment waterproofing to a depth of about 10 to 100 meters. Further, the reference pressure related to design and manufacturing may be set to be slightly higher than 20 atmospheres (exceeding by about 5%, for example) with a margin.

Further, in the above embodiment, the electronic device 1 is described as an example of an electronic wristwatch, but the present invention is not limited to this. Other electronic devices may be used.
In addition, specific details such as specific configurations, structures, and materials shown in the above embodiments can be changed as appropriate without departing from the scope of the present invention.

Although several embodiments of the present invention have been described, the scope of the present invention is not limited to the embodiments described above, but includes the scope of the invention described in the claims and equivalents thereof.
The invention described in the scope of claims originally attached to the application form of this application is additionally described below. The claim numbers in the appendix are as in the claims originally attached to the filing of this application.

[Appendix]
<Claim 1>
a waterproof vibrating membrane;
a support member positioned side by side with the vibrating membrane in a certain direction and having a through hole;
an adhesive layer positioned between the vibrating membrane and the support member and having an opening in a range including the through hole;
comprising an acoustic transmission unit having
The through-hole is positioned within a range encompassed by the opening in plan view along the certain direction in a state in which the sound transmission portion is pressed in the certain direction by a predetermined force. A sound system characterized by:
<Claim 2>
The through holes are a plurality of small holes,
The edge of the opening of the adhesive layer is deformed in a direction along the adhesive surface of the adhesive layer when the sound transmission portion is pressed with the predetermined force from the outer periphery of the range including all the small holes. 2. The acoustic device of claim 1, separated by a distance greater than an amount.
<Claim 3>
3. The acoustic device according to claim 1, wherein said opening is circular.
<Claim 4>
The acoustic device according to any one of claims 1 to 3, wherein the support member is positioned closer to the inner surface of the sound transmission section than the vibrating membrane.
<Claim 5>
The acoustic device according to any one of claims 1 to 4, wherein the support member is located closer to the outer surface of the sound transmission section than the vibrating membrane.
<Claim 6>
The acoustic device according to any one of claims 1 to 5, wherein the adhesive layer is a double-sided tape.
<Claim 7>
The acoustic device according to any one of claims 1 to 6, wherein said predetermined force is approximately 20 atmospheres.
<Claim 8>
an acoustic converter that converts between sound waves and electrical signals;
a passage that connects the acoustic conversion unit and the acoustic transmission unit;
with
The acoustic device according to any one of claims 1 to 7, wherein the opening has an area equal to or larger than the opening area of the passage.
<Claim 9>
An electronic device comprising the acoustic device according to any one of claims 1 to 8.

1 Electronic device 10 Acoustic device 11 Acoustic conversion unit 12 Rubber edge 13 Acoustic transmission unit 131 Vibration membranes 132, 1321, 1322 Adhesive tape 132a Openings 133, 1331, 1332 Support member 133a Small hole 14 Waterproof packing 15 Sound hole case 151 Air passage 152 Projection Part 16 Compression plate 161 Through hole 17 Dustproof plate 19 Exterior member 20 Housings 201, 202 Recess 203 Air passage 30 Windshield 40 Back cover 41 Metal plate 50 Display screen 60 Operation part

Claims (9)

a waterproof vibrating membrane;
a support member positioned side by side with the vibrating membrane in a certain direction and having a through hole;
an adhesive layer positioned between the vibrating membrane and the support member and having an opening in a range including the through hole;
comprising an acoustic transmission unit having
The through-hole is positioned within a range encompassed by the opening in plan view along the certain direction in a state in which the sound transmission portion is pressed in the certain direction by a predetermined force. A sound system characterized by: The through holes are a plurality of small holes,
The edge of the opening of the adhesive layer is deformed in a direction along the adhesive surface of the adhesive layer when the sound transmission portion is pressed with the predetermined force from the outer periphery of the range including all the small holes. 2. The acoustic device of claim 1, separated by a distance greater than an amount. 3. The acoustic device according to claim 1, wherein said opening is circular. The acoustic device according to any one of claims 1 to 3, wherein the support member is positioned closer to the inner surface of the sound transmission section than the vibrating membrane. The acoustic device according to any one of claims 1 to 4, wherein the support member is located closer to the outer surface of the sound transmission section than the vibrating membrane. The acoustic device according to any one of claims 1 to 5, wherein the adhesive layer is a double-sided tape. The acoustic device according to any one of claims 1 to 6, wherein said predetermined force is approximately 20 atmospheres. an acoustic converter that converts between sound waves and electrical signals;
a passage that connects the acoustic conversion unit and the acoustic transmission unit;
with
The acoustic device according to any one of claims 1 to 7, wherein the opening has an area equal to or larger than the opening area of the passage. An electronic device comprising the acoustic device according to any one of claims 1 to 8.

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