Acoustic device

Abstract

An acoustic device (1) is provided with a matching part (100) provided to a wall surface (91A) of a housing (90), the matching part (100) matching acoustic impedances in order to propagate sound from a sound source (50) through the housing (90). The matching part (100) has a support frame (20) having end surfaces (21) that is in contact with the wall surface (91A) of the housing (90), a vibration membrane (10) supported by the support frame (20), and attachment parts (30) that attach the support frame (20) to the wall surface (91A) of the housing (90).

Description

sound equipment

[0001] The present invention relates to an acoustic device.

[0002] An acoustic device is a device that propagates sound from a sound source. For example, an acoustic device includes a sound source and a housing that houses the sound source. The housing obstructs the propagation of sound. For this reason, acoustic devices require a method for propagating sound through the housing.

[0003] For example, Patent Document 1 discloses an ultrasonic transducer including a first acoustic transducer, a second acoustic transducer, and a cylindrical housing with a bottom. The second acoustic transducer has a second membrane portion, an annular portion that supports the second membrane portion, and an acoustic matching plate that faces the second membrane portion with a gap therebetween and forms a sealed space between the second membrane portion and the housing.

[0004] International Publication No. 2021 / 192417

[0005] In Patent Document 1, matching acoustic impedance requires high accuracy in the spacing between the acoustic matching plate and the second membrane. However, if an adhesive is interposed between the acoustic matching plate and the second membrane, variations in the thickness of the adhesive reduce the accuracy of the spacing between the acoustic matching plate and the second membrane. This can result in insufficient matching of acoustic impedance, resulting in a decrease or variation in the sound pressure of the sound propagating into the external space.

[0006] The present invention has been made in view of the above circumstances, and has as its object to provide an acoustic device that can maximize the acoustic propagation efficiency and reduce variations.

[0007] An acoustic device according to one aspect of the present invention includes a matching section provided on a wall surface of a housing, the matching section matching acoustic impedance to propagate sound from a sound source through the housing, the matching section including a support frame having an end face that contacts the wall surface of the housing, a vibration membrane supported by the support frame, and an attachment section that attaches the support frame to the wall surface of the housing.

[0008] Another aspect of the present invention provides an acoustic device comprising a sound source and a matching section provided on a wall surface of a housing, the matching section matching acoustic impedance to propagate sound from the sound source through the housing, the matching section comprising a support frame having an end face that contacts the wall surface of the housing, a vibration membrane supported by the support frame, and an attachment section that attaches the support frame to the wall surface of the housing.

[0009] Another aspect of the present invention provides an acoustic device comprising a housing, a sound source, and a matching section provided on a wall surface of the housing that matches acoustic impedance to propagate sound from the sound source through the housing, the matching section having a support frame with an end face that contacts the wall surface of the housing, a vibration membrane supported by the support frame, and an attachment section that attaches the support frame to the wall surface of the housing.

[0010] According to the present invention, it is possible to provide an acoustic device that can maximize the acoustic propagation efficiency and reduce variations.

[0011] 1. An exploded perspective view of an acoustic device according to the first embodiment. 2. A cross-sectional view of the acoustic device according to the first embodiment. 3. A plan view of a matching portion according to the first embodiment. 4. A cross-sectional view of a matching portion according to the fifth embodiment. 5. A cross-sectional view of a matching portion according to the sixth embodiment. 6. A cross-sectional view of a matching portion according to the seventh embodiment. 7. A cross-sectional view of a matching portion according to the eighth embodiment. 8. A cross-sectional view of a matching portion according to the ninth embodiment. 9. A cross-sectional view of an acoustic device according to the tenth embodiment. 10. A cross-sectional view of an acoustic device according to the eleventh embodiment. 12. A cross-sectional view of an acoustic device according to the thirteenth embodiment. 14. A cross-sectional view of an acoustic device according to the fourteenth embodiment. 15. A cross-sectional view of a matching portion according to the fifteenth embodiment. 15. A cross-sectional view of an acoustic device according to the fifteenth embodiment. 16. A cross-sectional view of an acoustic device according to the sixteenth embodiment.

[0012] Hereinafter, embodiments of the present invention will be described. In the following description of the drawings, the same or similar components are denoted by the same or similar reference numerals. The drawings are illustrative, and the dimensions and shapes of each part are schematic. The technical scope of the present invention should not be interpreted as being limited to the embodiments.

[0013] First Embodiment First, the configuration of an acoustic device according to a first embodiment will be described with reference to Fig. 1 and Fig. 2. Fig. 1 is an exploded perspective view of the acoustic device according to the first embodiment. Fig. 2 is a cross-sectional view of the acoustic device according to the first embodiment.

[0014] The acoustic device 1 includes a housing 90 , a matching section 100 , and a sound-generating component 200 .

[0015] The housing 90 is a container that houses the matching unit 100 and the sound-generating component 200 in its internal space, and is specifically a housing for a sound-emitting product, such as a home appliance or a mobile device. The housing 90 seals the internal space. The shape of the housing 90 is, for example, cylindrical. The materials of the main wall portions 91, 92 and the side wall portion 93 are not particularly limited and may be appropriately selected from metal, ceramic, semiconductor, resin, etc. The materials of the main wall portions 91, 92 and the side wall portion 93 are, for example, the same, but may also be different from each other.

[0016] The housing 90 has main wall portions 91 and 92 and a side wall portion 93. The main wall portion 91 and the main wall portion 92 face each other. The main wall portions 91 and 92 are disk-shaped. One end of the side wall portion 93 is connected to an end of the main wall portion 91, and the other end of the side wall portion 93 is connected to an end of the main wall portion 92. In other words, the side wall portion 93 connects the end of the main wall portion 91 and the end of the main wall portion 92. The side wall portion 93 is cylindrical in shape.

[0017] The main wall portion 91 has an inner wall surface 91A provided on the side facing the main wall portion 92 and the side wall portion 93, and an outer wall surface 91B provided on the opposite side from the inner wall surface 91A. The main wall portion 92 has an inner wall surface 92A provided on the side facing the main wall portion 91 and the side wall portion 93, and an outer wall surface 92B provided on the opposite side from the inner wall surface 92A. The side wall portion 93 has an inner wall surface 93A provided on the side facing the main wall portions 91 and 92, and an outer wall surface 93B provided on the opposite side from the inner wall surface 93A. The inner wall surfaces 91A, 92A, and 93A are inner surfaces of the housing 90 that surround the internal space in which the matching portion 100 and the sound-producing component 200 are housed. The outer wall surfaces 91B, 92B, and 93B are outer surfaces of the housing 90 that are exposed to the external space. The inner wall surfaces 91A, 92A, and 93A and the outer wall surfaces 91B, 92B, and 93B correspond to an example of the "wall surfaces of the housing."

[0018] The housing is not limited to a configuration in which the internal space is sealed. The housing does not have to be sealed, i.e., the internal space of the housing may be connected to the external space. In this case, a cylindrical or slit-shaped hole may be formed in the main wall or side wall of the housing. The shape of the housing is not limited to a cylindrical shape as long as it can accommodate the matching section and the sound-generating components, and may be, for example, a polygonal cylinder, an elliptical cylinder, a polygonal truncated pyramid, a circular truncated cone, an elliptical truncated cone, a sphere, an elliptical sphere, or a combination thereof.

[0019] The matching unit 100 propagates sound from a sound source 50 (described later) included in the sound-generating component 200 through the housing 90. The matching unit 100 is provided on an inner wall surface 91A of the main wall 91. The matching unit 100 matches the acoustic impedance of a gas filling the internal space of the housing 90 with the acoustic impedance of the main wall 91 of the housing 90 at the acoustic frequency of the sound source 50. The gas in the internal space of the housing 90 is, for example, air, and the acoustic impedance of air is significantly different from the acoustic impedance of the main wall 91 of the housing 90. Sound is reflected at the boundary between media with significantly different acoustic impedances, but because the matching unit 100 matches the acoustic impedances, reflection of sound at the inner wall surface 91A of the main wall 91 is suppressed. In other words, the matching unit 100 efficiently propagates sound emitted from the sound source 50 in the internal space of the housing 90 to the external space of the housing 90.

[0020] The internal space of housing 90 is filled with, for example, air, but is not limited to this as long as it is filled with a fluid that can propagate the sound emitted by sound-generating component 200. The fluid filling the internal space of housing 90 may be an inert gas such as a rare gas or nitrogen gas, a mixed gas containing air, or a liquid such as water.

[0021] The matching section 100 includes a support frame 20 , a vibration membrane 10 , and an attachment section 30 .

[0022] The support frame 20 is provided on an inner wall surface 91A of the main wall portion 91 of the housing 90. The support frame 20 supports the vibration membrane 10. The support frame 20 has a tubular shape, for example, a cylindrical shape. The material of the support frame 20 is not particularly limited, and may be appropriately selected from metal, ceramic, semiconductor, resin, etc.

[0023] The support frame 20 has end faces 21 and 22, an inner surface 20A, and an outer surface 20B.

[0024] The end face 21 is a frame-shaped surface connecting the inner surface 20A and the outer surface 20B on the side facing the main wall portion 91. The end face 22 is a frame-shaped surface connecting the inner surface 20A and the outer surface 20B on the side facing the main wall portion 92. The end face 21 contacts the inner wall surface 91A of the main wall portion 91 of the housing 90. In other words, the end of the support frame 20 on the end face 21 side is a closed end closed by the inner wall surface 91A. Here, "the end face 21 contacts the inner wall surface 91A" means that at least a portion of the end face 21 and the inner wall surface 91A are in direct contact, and no gap or adhesive exists between at least a portion of the contacting end face 21 and the inner wall surface 91A. A sound source 50 (described later) of the sound-generating component 200 is provided at the end of the support frame 20 on the end face 22 side. The end of the support frame 20 on the end face 21 side corresponds to an example of "one end of the support frame," and the end of the support frame 20 on the end face 22 side corresponds to an example of "the other end of the support frame."

[0025] The inner surface 20A is a side surface provided on the opposite side to the outer surface 20B. The outer surface 20B is a side surface provided on the side facing the side wall portion 93 of the housing 90. The vibration membrane 10 is connected to a position away from both the end surface 21 and the end surface 22 of the inner surface 20A. An attachment portion 30 is provided near the end surface 21 of the outer surface 20B.

[0026] The diaphragm 10 is supported by the support frame 20. Specifically, the diaphragm 10 is connected to the inner surface 20A of the support frame 20 around the entire periphery. The diaphragm 10 is provided at a predetermined distance from the inner wall surface 91A of the main wall portion 91 of the housing 90. The diaphragm 10 divides the space surrounded by the inner surface 20A of the support frame 20 into a space on the end surface 21 side and a space on the end surface 22 side. The space surrounded by the main wall portion 91 of the housing 90, the support frame 20, and the diaphragm 10 is sealed. When viewed from above in the direction in which the main wall portion 91 and the main wall portion 92 overlap (hereinafter simply referred to as "planar view"), the center of the diaphragm 10 overlaps with the centers of the main wall portions 91 and 92 of the housing 90, for example, but is not limited thereto. In the planar view, the center of the diaphragm 10 may be spaced apart from the centers of the main wall portions 91 and 92.

[0027] The diaphragm 10 has a thickness along the direction in which the main wall portions 91 and 92 face each other, and has a main surface extending along the inner wall surfaces 91A and 92A of the main wall portions 91 and 92. When the direction in which the diaphragm 10 has a thickness is defined as the "thickness direction," the diaphragm 10 is held by the support frame 20 so as to be vibrable in the thickness direction. When the diaphragm 10 is vibrated by sound propagated from the sound-producing component 200, the matching unit 100 matches the acoustic impedance of the internal space of the housing 90 with the acoustic impedance of the main wall portion 91 of the housing 90. The material of the diaphragm 10 is not particularly limited and may be appropriately selected from metal, ceramic, semiconductor, resin, and the like. The material, mass, position, and the like of the diaphragm 10 are appropriately designed depending on the acoustic frequency of the sound-producing component 200 whose acoustic impedance is to be matched, the acoustic impedance of the gas in the internal space of the housing 90, the acoustic impedance of the main wall portion 91 of the housing 90, and the like.

[0028] The mounting portion 30 is a component for mounting the support frame 20 to the inner wall surface 91A of the main wall portion 91 of the housing 90. By attaching the mounting portion 30 to the inner wall surface 91A, the matching portion 100 is fixed to the main wall portion 91. The method of attaching the mounting portion 30 to the inner wall surface 91A is not particularly limited. For example, the mounting portion 30 may be engaged with a protrusion provided on the inner wall surface 91A, fitted into a protrusion provided on the inner wall surface 91A, or screwed into a groove provided on the inner wall surface 91A. The mounting portion 30 and the main wall portion 91 may be joined by a joining member such as a screw or adhesive. When the mounting portion 30 is engaged, fitted, or screwed into the inner wall surface 91A, the mounting portion 30 may be in contact with the inner wall surface 91A. When the mounting portion 30 is joined to the inner wall surface 91A by a joining member such as a screw or adhesive, the mounting portion 30 may be in contact with the inner wall surface 91A or may be separated from the inner wall surface 91A.

[0029] The mounting portions 30 are provided on the outer surface 20B of the support frame 20. The mounting portions 30 are provided at the end of the support frame 20 on the end surface 21 side. For example, the mounting portions 30 are provided closer to the end surface 21 side of the support frame 20 than the vibration membrane 10. As shown in FIG. 3 , the mounting portions 30 are provided at two locations on the outer surface 20B. The mounting portions 30 are provided at positions that face each other across the vibration membrane 10 in a plan view.

[0030] The position of the attachment portion is not limited to the above. The attachment portion may be provided on the outer surface of the support frame at the end opposite to the end connected to the housing of the support frame. The attachment portion may be provided on the outer surface of the support frame from the end connected to the housing of the support frame to the opposite end. The attachment portion may be provided on the end surface of the support frame opposite to the end surface that contacts the housing. Furthermore, the attachment portion may be provided at one location on the outer surface of the support frame, or at three or more locations.

[0031] The sound-producing component 200 generates sound. The sound-producing component 200 is connected to the end of the matching section 100 on the side of the end surface 22. The sound-producing component 200 includes a sound source 50 and a wiring 60.

[0032] The sound source 50 is supported by the support frame 20. Specifically, the sound source 50 is connected to the end of the support frame 20 on the end face 22 side, around the entire periphery of the inner surface 20A. The sound source 50 faces the vibration membrane 10 with a gap in between in the thickness direction. The sound source 50 is a piezoelectric vibration element having, for example, quartz crystal, PZT, AlN, lithium niobate, or lithium tantalate as a piezoelectric body.

[0033] The sound source 50 has a thickness along the direction in which the main wall portions 91 and 92 face each other, and has a main surface extending along the inner wall surfaces 91A and 92A of the main wall portions 91 and 92. The sound source 50 is held by the support frame 20 so as to be able to vibrate in the vibration direction of the diaphragm 10. In a plan view, the center of the sound source 50 overlaps the center of the main wall portions 91 and 92 of the housing 90.

[0034] The sound source is not limited to the above. The sound source may be connected to the end surface 22 of the support frame 20 instead of the inner surface 20A. If the sound source is a vibration element, the driving force that vibrates the sound source may be electrostatic force or electromagnetic force. The sound source may also be a case-attached buzzer or speaker.

[0035] The wiring 60 applies an electric signal to the sound source 50. Although not shown in the figure, the wiring 60 connects the sound source 50 to an external circuit. The wiring 60 is either drawn to the outside of the acoustic device 1 via the main wall portion 91, the main wall portion 92, or the side wall portion 93, or is connected to a power source provided inside the acoustic device 1.

[0036] As described above, according to this embodiment, the acoustic device 1 includes a matching unit 100 provided on the inner wall surface 91A of the housing 90. The matching unit 100 matches acoustic impedance so that sound from the sound source 50 propagates through the housing 90. The matching unit 100 includes a support frame 20 having an end face 21 that contacts the inner wall surface 91A of the housing 90, a vibration membrane 10 that is supported by the support frame 20, and an attachment unit 30 that attaches the support frame 20 to the inner wall surface 91A of the housing 90.

[0037] According to this, since the support frame 20 is in direct contact with the main wall surface 91 of the housing 90, if the support frame 20 is designed to hold the diaphragm 10 with the desired positional accuracy, the thickness of the bonding portion, such as an adhesive layer, will not affect the mounting of the matching unit 100 to the housing 90. This reduces variation in the gap between the diaphragm 10 and the main wall portion 91 of the housing 90. This improves the accuracy of impedance matching between the acoustic impedance of the internal space of the housing 90 and the acoustic impedance of the main wall portion 91 of the housing 90. In other words, it is possible to maximize the propagation efficiency of sound emitted from the sound source 50 and propagating through the housing 90 and reduce variation.

[0038] In one aspect of this embodiment, the attachment portions 30 are provided at two or more locations on the support frame 20 .

[0039] This makes it possible to prevent the support frame 20 from being tilted relative to the inner wall surface 91A of the housing 90 when the mounting portion 30 is connected. Therefore, it is possible to prevent variation in the orientation of the matching portion 100 relative to the housing 90, and reduce variation in the gap between the diaphragm 10 and the main wall portion 91 of the housing 90.

[0040] In this embodiment, the matching unit and the sound source are provided in the internal space of the housing, but they may also be provided in the external space of the housing. In this case, for example, a microphone that collects sound emitted from the sound source through the housing may be provided in the internal space of the housing. Also, in this embodiment, the sound source is connected to the matching unit, but the sound source may be provided away from the matching unit. One of the matching unit and the sound source may be provided in the internal space of the housing, and the other may be provided in the external space of the housing. Two matching units may be provided on both the inner wall surface and the outer wall surface of the housing, sandwiching the main wall portion of the housing.

[0041] Other embodiments will be described below. Note that components that are the same as or similar to those in the first embodiment are denoted by the same or similar reference numerals, and descriptions thereof will be omitted as appropriate. Furthermore, similar effects resulting from similar components will not be mentioned one after another.

[0042] Second Embodiment Next, the configuration of an acoustic device 2 according to a second embodiment will be described with reference to Fig. 4. Fig. 4 is a plan view of a matching section according to the second embodiment.

[0043] The matching portion 102 of the acoustic device 2 has attachment portions 32 in three locations. The three attachment portions 32 are provided at equal intervals in the circumferential direction of the outer surface 20B of the support frame 20. This makes it possible to further stabilize the posture of the matching portion 102.

[0044] Third Embodiment Next, the configuration of an acoustic device 3 according to a third embodiment will be described with reference to Fig. 5. Fig. 5 is a plan view of a matching section according to the third embodiment.

[0045] The matching portion 103 of the acoustic device 3 is provided in the shape of a continuous frame around the entire periphery of the outer surface 20B of the support frame 20. This makes it possible to further stabilize the posture of the matching portion 103.

[0046] Fourth Embodiment Next, the configuration of an acoustic device 4 according to a fourth embodiment will be described with reference to Fig. 6. Fig. 6 is a cross-sectional view of a matching section according to the fourth embodiment.

[0047] The matching section 104 of the acoustic device 4 further has a connection section 44 that connects the mounting section 34 and the main wall section 91 of the housing. The mounting section 34 is provided at a distance from the main wall section 91. In other words, the mounting section 34 is spaced apart from the main wall section 91. The connection section 44 is a screw that passes through the mounting section 34. The tip of the connection section 44 is screwed into the main wall section 91. The head of the connection section 44 is located on the opposite side of the mounting section 34 from the side facing the main wall section 91.

[0048] Fifth Embodiment Next, the configuration of an acoustic device 5 according to a fifth embodiment will be described with reference to Fig. 7. Fig. 7 is a cross-sectional view of a matching section according to the fifth embodiment.

[0049] The matching section 105 of the acoustic device 5 further has a connection section 45 that connects the mounting section 35 and the main wall section 91 of the housing. The mounting section 35 is provided at a distance from the main wall section 91. The connection section 45 is an adhesive that bonds the mounting section 35 and the main wall section 91. The connection section 45 is provided in the gap between the main wall section 91 and the mounting section 35.

[0050] Sixth Embodiment Next, the configuration of an acoustic device 6 according to a sixth embodiment will be described with reference to Fig. 8. Fig. 8 is a cross-sectional view of a matching section according to the sixth embodiment.

[0051] In the matching section 106 of the acoustic device 6, the mounting section 36 is provided from the end on the end face 21 side of the support frame 20 to the end on the end face 22 side. A recess is provided in the inner wall surface 91A of the main wall section 91 of the housing in an area facing the mounting section 36. In other words, a step is provided on the inner wall surface 91A between the area facing the support frame 20 and the area facing the mounting section 36. This provides a gap between the mounting section 36 and the main wall section 91. The mounting section 36 and the main wall section 91 are connected by a connecting section 46, which is a screw that passes through the mounting section 36.

[0052] Seventh Embodiment Next, the configuration of an acoustic device 7 according to a seventh embodiment will be described with reference to Fig. 9. Fig. 9 is a cross-sectional view of a matching section according to the seventh embodiment.

[0053] The shape of the main wall portion 91 of the housing of the acoustic device 7 is the same as the shape of the main wall portion 91 of the housing of the acoustic device 6. An adhesive 47 is provided in the recess of the main wall portion 91, and the mounting portion 37 and the main wall portion 91 are connected by the adhesive 47.

[0054] Eighth Embodiment Next, the configuration of an acoustic device 8 according to an eighth embodiment will be described with reference to Fig. 10. Fig. 10 is a cross-sectional view of a matching section according to the eighth embodiment.

[0055] In the matching section 108 of the acoustic device 8, the mounting section 38 is configured to be detachable from the support frame 20. One end of the mounting section 38 contacts the end face 22 of the support frame 20, and urges the support frame 20 toward the main wall section 91 of the housing. The other end of the mounting section 38 faces the main wall section 91 with a gap between them, and is fastened with a connection section 48 by a screw.

[0056] Ninth Embodiment Next, the configuration of an acoustic device 9 according to a ninth embodiment will be described with reference to Fig. 11. Fig. 11 is a cross-sectional view of a matching section according to the ninth embodiment.

[0057] In the matching section 109 of the acoustic device 9, the mounting section 39 is provided at the end on the end face 22 side of the support frame 20. The housing 990 is configured to be separable at the center of the side wall section 993. The housing 990 has a first section 99A including a main wall section 991, and a second section 99B including a main wall section 992. The first section 99A and the second section 99B are connected to each other by, for example, engagement, fitting, or screwing to form the housing 990.

[0058] The support frame 20 is sandwiched between a first portion 99A and a second portion 99B. The second portion 99B has a protrusion Z that contacts the mounting portion 39. The end surface 21 of the support frame 20 abuts against the first portion 99A, and the support frame 20 is urged toward the second portion 99B by the elasticity of the first portion 99A connected to the second portion 99B. The mounting portion 39 abuts against a protrusion 995 of the second portion 99B, and the support frame 20 is urged toward the first portion 99A by the elasticity of the second portion 99B connected to the first portion 99A.

[0059] This allows the end surface 21 of the support frame 20 to come into contact with the main wall portion 991 without providing a connecting portion, thereby simplifying the manufacturing process.

[0060] Tenth Embodiment Next, the configuration of an acoustic device A0 according to a tenth embodiment will be described with reference to Fig. 12. Fig. 12 is a cross-sectional view of the acoustic device according to the tenth embodiment.

[0061] In the acoustic device A0, the matching unit 110 is spaced apart from the sound source 50. Specifically, the support frame 20 of the matching unit 110 is disposed apart from the sound source 50. The sound source 50 is provided, for example, on an inner wall surface 92A of the main wall portion 92 of the housing 90. When the inner wall surface 91A on which the matching unit 110 is provided is viewed in plan, the center of the sound source 50 overlaps, for example, with the center of the diaphragm 10.

[0062] The arrangement of the sound source 50 is not limited to the above. In plan view, the center of the sound source 50 may be spaced apart from the center of the diaphragm 10. The sound source 50 may also be provided on the inner wall surface 93A of the side wall portion 93.

[0063] Eleventh Embodiment Next, the configuration of an acoustic device A1 according to an eleventh embodiment will be described with reference to Fig. 13. Fig. 13 is a cross-sectional view of the acoustic device according to the eleventh embodiment.

[0064] In the acoustic device A1, the matching section 111 is provided in the external space of the housing 90. Specifically, the matching section 111 is provided on an outer wall surface 91B of the main wall section 91 of the housing 90. The support frame 20 is attached to the outer wall surface 91B of the main wall section 91 by the attachment sections 30, and the end faces 21 of the support frame 20 are in contact with the outer wall surface 91A. The sound source 50 is provided on, for example, an inner wall surface 92A of the main wall section 92 of the housing 90.

[0065] The arrangement of the matching portion 111 is not limited to the above. The matching portion 111 may be provided on the outer wall surface 92B of the main wall portion 92 or on the outer wall surface 93B of the side wall portion 93.

[0066] Twelfth Embodiment Next, the configuration of an acoustic device A2 according to a twelfth embodiment will be described with reference to Fig. 14. Fig. 14 is a cross-sectional view of the acoustic device according to the twelfth embodiment.

[0067] The acoustic device A2 further includes a sound collector 70. The sound collector 70 is a microphone for collecting sound emitted by the sound source 50. The matching unit 112 and the sound collector 70 are provided in the internal space of the housing 90, and the sound source 50 is located in the external space of the housing 90. The matching unit 112 efficiently propagates the sound emitted by the sound source 50 to the sound collector 70 through the housing 90. The sound collector 70 is provided, for example, on the inner wall surface 92A of the main wall portion 92, and the matching unit 112 is provided, for example, on the inner wall surface 91A of the main wall portion 91. The position of the sound source 50 is not particularly limited. For example, the acoustic device A2 is an abnormal sound inspection device, and the sound source 50 is the equipment to be inspected.

[0068] The arrangement of the matching portion 112 and the sound collector 70 is not limited to the above. The matching portion 112 may be provided on the inner wall surface 92A of the main wall portion 92 or the inner wall surface 93A of the side wall portion 93, and the sound collector 70 may be provided on the inner wall surface 91A of the main wall portion 91 or the inner wall surface 93A of the side wall portion 93. The matching portion 112 may be provided on the outer wall surfaces 91B, 92B of the main wall portions 91, 92 or the outer wall surface 93B of the side wall portion 93.

[0069] The acoustic device A2 may include, instead of the sound collector 70, another device that acquires and utilizes the sound of the sound source 50.

[0070] Thirteenth Embodiment Next, the configuration of an acoustic device A3 according to a thirteenth embodiment will be described with reference to Fig. 15. Fig. 15 is a cross-sectional view of the acoustic device according to the thirteenth embodiment.

[0071] Unlike the other embodiments, the acoustic device A3 includes a case 51A, and is configured as a cased sound source in which the sound source 50 is protected by the case 51A. While a support frame is provided to support the diaphragm 10 and the sound source 50 in the other embodiments, the present embodiment uses the case 51A instead of the support frame. The case 51A is provided on the inner wall surface 91A of the main wall portion 91 of the housing 90. The case 51A has a cylindrical portion 52A and a lid portion 53A. As shown in FIG. 15 , the cylindrical portion 52A of the case 51A supports the diaphragm 10 and the sound source 50. In other words, the cylindrical portion 52A of the case 51A of the sound source 50 functions as a support frame for the matching portion 113. The cylindrical portion 52A has an end surface 521 that contacts the main wall portion 91 of the housing 90 and an end surface 522 that is away from the housing 90. The lid portion 53A of the case 51A is connected to the end surface 522 of the cylindrical portion 52A and is provided at a distance from the sound source 50. The lid portion 53A has a vent (not shown) for mitigating pressure changes inside the case 51A due to vibrations of the sound source 50, and incompletely closes the cylindrical portion 52A. However, the lid portion 53A may completely close the cylindrical portion 52A. In addition, an extraction electrode (not shown) is provided from the cylindrical portion 52A of the case 51A to the lid portion 53A, thereby electrically connecting the sound source 50 to the outside of the case 51A. The case 51A is fixed to the main wall portion 91 by the mounting portion 30.

[0072] Fourteenth Embodiment Next, the configuration of an acoustic device A4 according to a fourteenth embodiment will be described with reference to Fig. 16. Fig. 16 is a cross-sectional view of the acoustic device according to the fourteenth embodiment.

[0073] The fourteenth embodiment differs from the thirteenth embodiment in the structure of the case and the presence or absence of a support frame. In the acoustic device A4 shown in Fig. 16, the case 51B of the sound source 50 and the support frame 20 of the matching unit 100 are provided as separate bodies, with the support frame 20 supporting the diaphragm 10 and the case 51B supporting the sound source 50. An end face 521 of the cylindrical portion 52B of the case 51B that is closer to the main wall portion 91 is connected to an end face 22 of the support frame 20 that is farther from the main wall portion 91. The internal space of the cylindrical portion 52B of the case 51B is in communication with the internal space of the support frame 20.

[0074] <Fifteenth embodiment> Next, the configuration of an acoustic device A5 according to a fifteenth embodiment will be described with reference to Fig. 17 and Fig. 18. Fig. 17 is a plan view of a matching section according to the fifteenth embodiment. Fig. 18 is a cross-sectional view of the acoustic device according to the fifteenth embodiment.

[0075] The matching unit 100A of the acoustic device A5 differs from the first embodiment in the shape of the support frame. Specifically, as shown in FIG. 17 , the support frame 24 of the matching unit 100A has a circular inner surface 24A and a rectangular outer surface 24B in a plan view. The acoustic device A5 also has mounting portions 30A and protrusions 30B that secure the support frame 24 to an inner wall surface 91A. As shown in FIG. 17 , the mounting portions 30A are provided on the outer surface 24B so as to sandwich the support frame 24 from both sides. As shown in FIG. 18 , the protrusions 30B are provided on the inner wall surface 91A of the housing 90 so as to engage with the mounting portions 30A. When engaged with the protrusions 30B, the mounting portions 30A are pressed against the inner wall surface 91A by the protrusions 30B. When fixing the matching part 100A to the housing 90, the mounting part 30A is fitted into the protrusion 30B while sliding along the inner wall surface 91A and the protrusion 30B. In this way, the protrusion 30B functions as a slide rail for fixing the mounting part 30A.

[0076] Sixteenth Embodiment Next, the configuration of an acoustic device A6 according to a sixteenth embodiment will be described with reference to Fig. 19. Fig. 19 is a cross-sectional view of the acoustic device according to the sixteenth embodiment.

[0077] The acoustic device A6 differs from the ninth embodiment in the method of fixing the support frame 20. Specifically, while in the ninth embodiment the support frame 20 is fixed using the protrusions 995 on the second portion 99B of the housing 90, in the sixteenth embodiment the support frame 20 is fixed using the fixing portion 80 of the substrate W connected to the second portion 99B. Specifically, the housing 990A is configured to be separable at the center of the side wall portion 93. The housing 990A has a first portion 99A including a main wall portion 91 and a second portion 99B including a main wall portion 92. The first portion 99A and the second portion 99B are connected to each other by, for example, engagement, fitting, or screwing to form the housing 990A. A connection portion 996 is provided from the inner wall surface 92A of the second portion 99B toward the main wall surface 91, and the substrate W is connected to the main wall surface 91 side of the connection portion 996. A fixing portion 80 is provided on the main wall surface 91 side of the substrate W. The fixing portion 80 is, for example, a spring terminal that electrically connects the substrate W to the sound source 50. However, the fixing portion 80 is not limited to a spring terminal, and may be a pin terminal that electrically connects the substrate W to the sound source 50, or an insulating spacer that does not contribute to the electrical connection between the substrate W and the sound source 50.

[0078] The support frame 20 is sandwiched between the first portion 99A and the second portion 99B via the substrate W. Specifically, an end face 21 of the support frame 20 abuts against the inner wall surface 91A of the main wall portion 91, and an end face 22 of the support frame 20 abuts against the fixing portion 80 of the substrate W. The support frame 20 is urged toward the substrate W by the elasticity of the first portion 99A. The support frame 20 is urged toward the first portion 99A by the elasticity of the second portion 99B and the substrate W. As a result, the support frame 20 is fixed between the main wall portion 91 and the main wall portion 92 within the housing 990A via the fixing portion 80 of the substrate W.

[0079] According to this embodiment, the substrate W is more elastically deformable than the housing 990A, and therefore the support frame 20 can be biased more strongly toward the first portion 99A than in the acoustic device 9 of the ninth embodiment. This improves the fixing strength of the support frame 20 and prevents the support frame 20 from shifting out of position. Furthermore, by using spring terminals for the fixing portions 80, the support frame 20 can be fixed to the housing 990A while electrically connecting the substrate W and the sound source 50 via the fixing portions 80. In other words, since the fixing portions are spring terminals, it is not necessary to provide a separate member for electrically connecting the substrate and the sound source. Furthermore, the elasticity of the spring terminals improves the biasing strength of the support frame 20 toward the first portion 99A, further improving the fixing strength of the support frame 20. Even when the fixing portions are pin terminals or spacers, the fixing strength of the support frame can be improved as long as the fixing portions are elastically deformable. Furthermore, when the fixing portions are pin terminals, it is not necessary to provide a separate member for electrically connecting the substrate and the sound source, as in the case of spring terminals.

[0080] Some or all of the embodiments of the present invention will be described below, but the present invention is not limited to the following descriptions.

[0081] <1> An acoustic device comprising a matching section provided on a wall surface of a housing, the matching section matching acoustic impedance in order to propagate sound from a sound source through the housing, the matching section comprising: a support frame having an end face that contacts the wall surface of the housing; a diaphragm supported by the support frame; and an attachment section that attaches the support frame to the wall surface of the housing.

[0082] <2> An acoustic device comprising: a sound source; and a matching unit provided on a wall surface of a housing, the matching unit matching acoustic impedance to propagate sound from the sound source through the housing, wherein the matching unit has a support frame having an end face that contacts the wall surface of the housing, a vibration membrane supported by the support frame, and an attachment unit that attaches the support frame to the wall surface of the housing.

[0083] <3> The acoustic device according to <1> or <2>, wherein the attachment portion is provided on an outer surface of the support frame.

[0084] <4> The acoustic device according to any one of <1> to <3>, wherein the attachment portions are provided at two or more locations on the support frame.

[0085] <5> The acoustic device according to any one of <1> to <4>, wherein the attachment portion is provided around the entire periphery of the support frame.

[0086] <6> The acoustic device according to any one of <1> to <5>, wherein the attachment portion is in contact with a wall surface of the housing that the support frame is in contact with.

[0087] <7> The acoustic device according to any one of <1> to <6>, wherein the attachment portion is spaced apart from a wall surface of the housing with which the support frame comes into contact.

[0088] <8> The acoustic device according to any one of <1> to <7>, further comprising a housing, wherein a step is provided on a wall surface of the housing between an area facing the support frame and an area facing the attachment portion.

[0089] <9> The acoustic device according to any one of <1> to <8>, wherein the attachment portion is configured to be detachable from the support frame.

[0090] <10> The acoustic device according to any one of <1> to <9>, further comprising a housing, wherein the housing has a first portion and a second portion connected to the first portion, and the support frame is sandwiched between the first portion and the second portion.

[0091] <11> The acoustic device according to any one of <1> to <10>, wherein the matching section is provided inside the housing.

[0092] <12> The acoustic device according to any one of <1> to <11>, wherein the matching unit is provided on the outside of the housing.

[0093] <13> The acoustic device according to any one of <1> to <12>, wherein the sound source is provided inside the housing.

[0094] <14> The acoustic device according to any one of <1> to <12>, wherein the sound source is provided outside the housing.

[0095] <15> The acoustic device according to any one of <1> to <14>, wherein the support frame is provided in a cylindrical shape, one end of the support frame is a closed end that is closed by a wall surface of the housing, and the other end of the support frame is provided with a sound source.

[0096] <16> The acoustic device according to any one of <1> to <14>, wherein the support frame is disposed away from the sound source.

[0097] <17> An acoustic device comprising: a housing; a sound source; and a matching unit provided on a wall surface of the housing, the matching unit matching acoustic impedance to propagate sound from the sound source through the housing, wherein the matching unit has a support frame having an end face that contacts the wall surface of the housing, a vibration membrane supported by the support frame, and an attachment unit that attaches the support frame to the wall surface of the housing.

[0098] As described above, it is possible to provide an acoustic device that can maximize the acoustic propagation efficiency and reduce variations.

[0099] The above-described embodiments are intended to facilitate understanding of the present invention and are not intended to limit the scope of the present invention. The present invention may be modified or improved without departing from its spirit, and equivalents are also included within the scope of the present invention. In other words, designs modified by those skilled in the art as appropriate to the embodiments and / or modifications are also encompassed within the scope of the present invention as long as they incorporate the characteristics of the present invention. For example, the elements and their arrangements, materials, conditions, shapes, sizes, etc. of the embodiments and / or modifications are not limited to those illustrated and can be modified as appropriate. Furthermore, the embodiments and modifications are merely examples, and it goes without saying that partial substitutions or combinations of the components shown in different embodiments and / or modifications are possible. These are also encompassed within the scope of the present invention as long as they incorporate the characteristics of the present invention.

[0100] DESCRIPTION OF SYMBOLS 1... Acoustic device 100... Matching portion 200... Sound-generating component 10... Vibration membrane 20... Support frame 21, 22... End surface 20A... Inner surface 20B... Outer surface 30... Mounting portion 50... Sound source 60... Wiring 90... Housing 91, 92... Main wall portion 93... Side wall portion 91A, 92A, 93A... Inner wall surface 91B, 92B, 93B... Outer wall surface

Claims

1. An acoustic device, comprising a matching portion provided on a wall surface of a housing, the matching portion matching acoustic impedance for propagating sound from a sound source through the housing. The matching portion includes a support frame having an end face contacting the wall surface of the housing, a vibration membrane supported by the support frame, and an attachment portion for attaching the support frame to the wall surface of the housing.

2. An acoustic device, comprising a sound source and a matching portion provided on a wall surface of a housing, the matching portion matching acoustic impedance for propagating sound from the sound source through the housing. The matching portion includes a support frame having an end face contacting the wall surface of the housing, a vibration membrane supported by the support frame, and an attachment portion for attaching the support frame to the wall surface of the housing.

3. The acoustic device according to claim 1 or 2, wherein the attachment portion is provided on an outer surface of the support frame.

4. The acoustic device according to any one of claims 1 to 3, wherein the attachment portion is provided at two or more locations on the support frame.

5. The acoustic device according to any one of claims 1 to 4, wherein the attachment portion is provided over the entire circumference of the support frame.

6. The acoustic device according to any one of claims 1 to 5, wherein the attachment portion is in contact with the wall surface of the housing where the support frame contacts.

7. The acoustic device according to any one of claims 1 to 6, wherein the attachment portion is spaced apart from the wall surface of the housing where the support frame contacts.

8. The acoustic device according to any one of claims 1 to 7, further comprising the housing, wherein a step is provided between a region of the wall surface of the housing facing the support frame and a region facing the attachment portion.

9. The acoustic device according to any one of claims 1 to 8, wherein the attachment portion is configured to be detachable from the support frame.

10. The acoustic device according to any one of claims 1 to 9, further comprising the housing, wherein the housing has a first portion and a second portion connected to the first portion, and the support frame is sandwiched between the first portion and the second portion.

11. The acoustic device according to any one of claims 1 to 10, wherein the matching portion is provided inside the housing.

12. The acoustic device according to any one of claims 1 to 11, wherein the matching portion is provided outside the housing.

13. The sound source is provided inside the housing, and the acoustic device according to any one of claims 1 to 12.

14. The sound source is provided outside the housing, and the acoustic device according to any one of claims 1 to 12.

15. The support frame is provided in a cylindrical shape, one end of the support frame is a closed end closed by the wall surface of the housing, and the sound source is provided at the other end of the support frame. The acoustic device according to any one of claims 1 to 14.

16. The support frame is arranged away from the sound source, and the acoustic device according to any one of claims 1 to 14.

17. An acoustic device comprising a housing, a sound source, and a matching portion provided on the wall surface of the housing for matching acoustic impedance to propagate sound from the sound source through the housing, the matching portion having a support frame having an end surface in contact with the wall surface of the housing, a vibration membrane supported by the support frame, and a mounting portion for mounting the support frame to the wall surface of the housing.

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