JP2011120021A - Microphone unit and portable apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a microphone unit capable of further reliably suppressing the occurrence of sound leakage. <P>SOLUTION: In this differential microphone unit (microphone unit) 100, an inner surface 22b (inner surface 23b) of a first recess 22 (second recess 23) of a cover 20 is tightly fitted to an outer surface 31c (outer surface 32c) of a first protrusion 31 (second protrusion 32) of a gasket 30, and the first recess 22 (second recess 23) of the cover 20 is fixedly engaged with the first protrusion 31 (second protrusion 32) of the gasket 30. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a microphone unit and a portable device, and more particularly to a microphone unit and a portable device including a sealing member including a convex portion having a sound hole.

  Conventionally, a microphone unit and a portable device including a sealing member including a convex portion having a sound hole are known (see, for example, Patent Document 1).

  In the above-mentioned Patent Document 1, a sound inlet capable of voice input is formed, and a lid having a concave cross section and a sound outlet (sound hole) are formed while being assembled so as to cover a concave portion of the lid. A sheet-like label having a convex region (convex portion), a sealing member (sealing member) formed with an opening closely contacting the sound outlet of the convex region, and the sound outlet of the opening of the sealing member are opposite A wireless telephone (portable device) including a microphone disposed on the side is disclosed. The space between the label and the lid from the sound inlet of the lid to the sound outlet of the convex region of the label functions as an acoustic duct. In addition, the lid on which the label is assembled is configured to be slidable (movable) with respect to the sealing member. By sliding the lid on which the label is assembled with respect to the sealing member, the convexity of the label When the surface of the shaped region and the surface of the sealing member come into contact with each other, the sound outlet formed in the label and the opening formed in the sealing member are connected to each other. Thereby, the sound (sound) that has entered from the sound inlet reaches the microphone of the main body through the acoustic duct, the sound outlet of the label, and the opening of the sealing member.

JP-T-2001-515313

  However, in the wireless telephone disclosed in Patent Document 1, the lid on which the label is assembled is configured to slide (move) with respect to the sealing member. For example, the lid on which the label is assembled slides. It is considered that there may be a gap between the sound outlet of the label and the sealing member when moving in a direction perpendicular to the moving direction (a direction away from the sealing member). In this case, the sound (sound) that enters from the sound entrance leaks between the label and the sealing member, which causes a problem that acoustic leakage occurs.

  The present invention has been made to solve the above-described problems, and one object of the present invention is to provide a microphone unit and a portable device that can more reliably suppress the occurrence of acoustic leakage. That is.

Means for Solving the Problems and Effects of the Invention

  A microphone unit according to a first aspect of the present invention is disposed on a substrate provided with a vibrating portion that vibrates due to sound pressure, a cover portion disposed on the substrate so as to cover the vibrating portion, and a surface of the cover portion. The sealing member includes a sealing member side sound hole, and a convex portion that surrounds the periphery of the sealing member side sound hole and protrudes from the surface of the sealing member to the cover portion side, The cover part includes a cover part side sound hole formed so as to be connected to the sealing member side sound hole of the sealing member, and a concave part disposed at a position corresponding to the convex part of the sealing member, and at least the cover The inner surface of the concave portion of the portion and the outer surface of the convex portion of the sealing member are in close contact, and the concave portion of the cover portion and the convex portion of the sealing member are fixedly engaged.

  In the microphone unit according to the first aspect, as described above, the cover portion and the sealing member are relatively moved by fixedly engaging the concave portion of the cover portion and the convex portion of the sealing member. Unlike the case where it is possible, the engagement between the convex portion and the concave portion is unlikely to be disengaged, so that the occurrence of acoustic leakage from between the cover portion and the sealing member can be more reliably suppressed. Further, when at least the inner surface of the concave portion of the cover portion and the outer surface of the convex portion of the sealing member are in close contact, for example, the cover portion is displaced in a direction perpendicular to the surface of the substrate with respect to the sealing member However, when the magnitude of the deviation is within the range of the height of the convex portion (the depth of the concave portion), the inner surface of the concave portion and the outer surface of the convex portion can be maintained in close contact with each other. The occurrence of acoustic leakage from between the cover portion and the sealing member can be more reliably suppressed.

  In the microphone unit according to the first aspect, the inner surface of the concave portion of the cover portion and the outer surface of the convex portion of the sealing member are preferably in close contact with each other, and the inner bottom surface of the concave portion of the cover portion on the sealing member side The concave portion of the cover portion and the convex portion of the sealing member are fixedly engaged with each other in a state where the surface of the convex portion of the sealing member is in close contact. If comprised in this way, between the inner surface of the recessed part of a cover part, and the outer surface of the convex part of a sealing member, and the inner bottom face by the side of the sealing member of the recessed part of a cover part, and the convex part of a sealing member Since both can be brought into close contact with the surface and can be kept in a fixedly engaged state, the occurrence of acoustic leakage can be more reliably suppressed.

  In the microphone unit according to the first aspect, preferably, the convex portion of the sealing member is press-fitted into the concave portion of the cover portion, so that at least the inner surface of the concave portion of the cover portion and the outer surface of the convex portion of the sealing member And the concave portion of the cover portion and the convex portion of the sealing member are fixedly engaged. If comprised in this way, unlike the case where the convex part of a sealing member and the recessed part of a cover part are contacting lightly, the convex part of a sealing member and the recessed part of a cover part can be firmly fixed. Further, it is possible to further improve the adhesion (airtightness) between the convex portion and the concave portion, and more effectively prevent the engagement between the convex portion and the concave portion.

  In the microphone unit according to the first aspect, preferably, the sealing member side sound hole of the sealing member includes a first sealing member side sound hole and a second sealing member side sound hole, and the sealing member The convex portion surrounds the periphery of the first sealing member side sound hole, and surrounds the first convex portion projecting from the surface of the sealing member toward the cover portion and the second sealing member side sound hole. And a second convex part projecting from the surface of the sealing member to the cover part side, and the cover part side sound hole of the cover part is formed so as to be connected to the first sealing member side sound hole Including a part side sound hole and a second cover part side sound hole formed so as to be connected to the second sealing member side sound hole, and the concave part of the cover part corresponds to the first convex part of the sealing member. A first concave portion disposed at a position and a second concave portion disposed at a position corresponding to the second convex portion of the sealing member. The sound reaches one side of the vibration part via the first cover part side sound hole, and the sound is transmitted to the other side of the vibration part via the second sealing member side sound hole and the second cover part side sound hole. By arriving, the differential pressure between the sound pressure of the sound reaching one side of the vibration part and the sound pressure of the sound reaching the other side of the vibration part is detected. If comprised in this way, it will sound in both between the 1st recessed part of a cover part, and the 1st convex part of a sealing member, and between the 2nd recessed part of a cover part, and the 2nd convex part of a sealing member. It is possible to more reliably suppress the occurrence of leak. Thereby, the sound pressure input from the first cover part side sound hole and the sound pressure input from the second cover part side sound hole are respectively applied to the back surface (one side) and the front surface (the other side) of the vibration part. By transmitting, the differential pressure can be detected accurately. As a result, it is possible to maximize the performance of suppressing far-field noise.

  In the microphone unit according to the first aspect, preferably, the protruding height of the convex portion of the sealing member is substantially equal to the depth of the concave portion of the cover portion. If comprised in this way, while being able to contact the inner surface of the recessed part of a cover part, and the outer surface of the convex part of a sealing member over the whole region of the protrusion direction of a convex part, the sealing member side of the recessed part of a cover part Since the inner bottom surface and the surface of the convex part of the sealing member can be brought into contact (contact), the adhesion between the concave part of the cover part and the convex part of the sealing member can be further improved.

  In the microphone unit according to the first aspect, preferably, either the inner side surface of the concave portion formed in the cover portion or the outer side surface of the convex portion formed on the sealing member is formed in a tapered shape. ing. If comprised in this way, when the recessed part of a cover part and the convex part of a sealing member are fitted together (it is made to engage), it is in any one taper part among the recessed part of a cover part, or the convex part of a sealing member. Accordingly, the concave portion of the cover portion and the convex portion of the sealing member are fitted together, so that the concave portion of the cover portion and the convex portion of the sealing member can be easily fitted (engaged easily).

  In this case, preferably, the sealing member is made of an elastically deformable material, and the outer surface of the convex portion formed on the sealing member is formed in a tapered shape, and the concave portion formed on the cover portion. The inner surface is formed in a substantially rectangular shape, and the width of the opening end of the concave portion of the cover portion is smaller than the width of the root portion of the convex portion of the sealing member. If comprised in this way, when the taper-shaped convex part of a sealing member and the substantially rectangular-shaped recessed part of a cover part are fitted together, the outer surface of the convex part of a sealing member will be elastically deformed inside. It will be pushed in. As a result, a biasing force acts on the concave portion of the cover portion toward the outer side of the concave portion, and thus the adhesion (air tightness) between the inner side surface of the concave portion of the cover portion and the outer side surface of the convex portion of the sealing member. Can be further improved.

  In the microphone unit according to the first aspect, preferably, at least one of the inner surface of the concave portion formed in the cover portion or the outer surface of the convex portion formed in the sealing member is formed in an uneven shape. Yes. If comprised in this way, with the uneven | corrugated shape formed in at least any one among the inner surface of the recessed part of a cover part, or the outer surface of the convex part of a sealing member, the recessed part of a cover part and the convex part of a sealing member The engagement state can be made more difficult to disengage.

  In the microphone unit according to the first aspect, preferably, the sealing member is made of an elastically deformable material, and the outer side surface of the convex portion of the sealing member conforms to the shape of the inner side surface of the concave portion of the cover portion. The cover is engaged with the inner surface of the recess of the cover part in a state of being elastically deformed. If comprised in this way, since the urging | biasing force acts toward the outer side of a recessed part in the recessed part of a cover part, the adhesiveness between the outer surface of the convex part of a sealing member and the inner surface of the recessed part of a cover part (Airtightness) can be improved more effectively.

  In the microphone unit according to the first aspect, preferably, the sealing member is disposed so as to seal between the back side of the product housing in which the microphone is accommodated and the cover portion. If comprised in this way, generation | occurrence | production of the acoustic leak from between the back surface side of the product housing | casing in which a microphone is accommodated, and a cover part can be suppressed with a sealing member.

  The microphone unit according to the first aspect preferably further includes a conductive shield member that is disposed between the cover portion and the sealing member and has an opening for allowing the convex portion of the sealing member to escape, The protruding height of the convex portion of the sealing member is larger than the thickness of the shield member. If comprised in this way, while removing noises, such as electromagnetic waves, with a shield member, the relationship between the outer surface of the part which protruded from the shield member among the convex parts of a sealing member, and the inner surface of the recessed part of a cover part The occurrence (acoustic contact) can easily suppress the occurrence of acoustic leakage.

  A portable device according to a second aspect of the present invention is disposed on a substrate provided with a vibrating portion that vibrates due to sound pressure, a cover portion disposed on the substrate so as to cover the vibrating portion, and a surface of the cover portion. The sealing member includes a sealing member-side sound hole and a convex portion that surrounds the periphery of the sealing member-side sound hole and protrudes from the surface of the sealing member toward the cover portion. Includes a cover part-side sound hole formed so as to be connected to the sealing member-side sound hole of the sealing member, and a concave part disposed at a position corresponding to the convex part of the sealing member, at least of the concave part of the cover part A microphone unit in which the inner surface and the outer surface of the convex portion of the sealing member are in close contact, and the concave portion of the cover portion and the convex portion of the sealing member are fixedly engaged, and a portable device in which the microphone unit is stored And the sealing member includes a back side of the portable device casing, a cover It is arranged so as to seal between the parts.

  In the mobile device according to the second aspect, as described above, the cover portion and the sealing member are relatively moved by fixedly engaging the concave portion of the cover portion and the convex portion of the sealing member. Unlike the case where it is possible, the engagement between the convex portion and the concave portion is unlikely to be disengaged, so that the occurrence of acoustic leakage from between the cover portion and the sealing member can be more reliably suppressed. Further, when at least the inner surface of the concave portion of the cover portion and the outer surface of the convex portion of the sealing member are in close contact, for example, the cover portion is displaced in a direction perpendicular to the surface of the substrate with respect to the sealing member However, when the magnitude of the deviation is within the range of the height of the convex portion (the depth of the concave portion), the inner surface of the concave portion and the outer surface of the convex portion can be maintained in close contact with each other. The occurrence of acoustic leakage from between the cover portion and the sealing member can be more reliably suppressed. In addition, the sealing member is disposed so as to seal between the back surface side of the portable device casing and the cover portion, so that the sealing member allows the microphone unit to be stored in the back surface side of the portable device casing. And the occurrence of acoustic leakage from between the cover portion and the cover portion can be suppressed.

It is a top view of a mobile telephone provided with the differential microphone unit by 1st Embodiment of this invention. It is an enlarged view of a mobile telephone provided with the differential microphone unit by 1st Embodiment of this invention. FIG. 3 is a cross-sectional view taken along line 300-300 in FIG. 2. It is sectional drawing which showed the state after the assembly of the mobile telephone housing | casing part of a mobile telephone provided with the differential microphone unit by 1st Embodiment of this invention, the recessed part of a cover part, and the convex part of a gasket. 1 is an exploded perspective view of a mobile phone including a differential microphone unit according to a first embodiment of the present invention. It is the top view seen from the upper surface side of the differential microphone unit by 1st Embodiment of this invention. It is the top view seen from the undersurface side of the differential microphone unit by a 1st embodiment of the present invention. It is sectional drawing which showed the path | route of the sound which entered the mobile telephone provided with the differential microphone unit by 1st Embodiment of this invention. It is sectional drawing which showed the state after the assembly of the mobile telephone housing | casing part of a mobile telephone provided with the differential microphone unit by 1st modification of 1st Embodiment of this invention, the recessed part of a cover part, and the convex part of a gasket. . It is sectional drawing which showed the state before the assembly of the mobile telephone housing | casing part of a mobile telephone provided with the differential microphone unit by 1st modification of 1st Embodiment of this invention, the recessed part of a cover part, and the convex part of a gasket. . It is sectional drawing which showed the state after the assembly of the mobile telephone housing | casing part of a mobile telephone provided with the differential microphone unit by the 2nd modification of 1st Embodiment of this invention, the recessed part of a cover part, and the convex part of a gasket. . It is sectional drawing which showed the state before the assembly of the mobile telephone housing | casing part of a mobile telephone provided with the differential microphone unit by the 2nd modification of 1st Embodiment of this invention, the recessed part of a cover part, and the convex part of a gasket. . It is sectional drawing which showed the state after the assembly of the mobile telephone housing | casing part of a mobile telephone provided with the differential microphone unit by the 3rd modification of 1st Embodiment of this invention, the recessed part of a cover part, and the convex part of a gasket. . It is sectional drawing which showed the state before the assembly of the mobile telephone housing | casing part of a mobile telephone provided with the differential microphone unit by the 3rd modification of 1st Embodiment of this invention, the recessed part of a cover part, and the convex part of a gasket. . It is sectional drawing which showed the state after the assembly of the mobile telephone housing | casing part of a mobile telephone provided with the differential microphone unit by the 4th modification of 1st Embodiment of this invention, the recessed part of a cover part, and the convex part of a gasket. . It is sectional drawing which showed the state before the assembly of the mobile telephone housing | casing part of a mobile telephone provided with the differential microphone unit by the 4th modification of 1st Embodiment of this invention, the recessed part of a cover part, and the convex part of a gasket. . It is sectional drawing which showed the state after the assembly of the mobile telephone housing | casing part of a mobile telephone provided with the differential microphone unit by the 5th modification of 1st Embodiment of this invention, the recessed part of a cover part, and the convex part of a gasket. . It is sectional drawing which showed the state before an assembly of the mobile telephone housing | casing part of a mobile telephone provided with the differential microphone unit of 1st Embodiment of this invention, the recessed part of a cover part, and the convex part of a gasket. . It is sectional drawing of a mobile telephone provided with the differential microphone unit by which the shield member is arrange | positioned between the gasket and cover part by 2nd Embodiment of this invention. It is the top view seen from the upper surface side of the differential microphone unit by the 1st modification of 1st and 2nd embodiment of this invention. It is the top view seen from the upper surface side of the differential microphone unit by the 2nd modification of 1st and 2nd embodiment of this invention. It is the top view seen from the upper surface side of the differential microphone unit by the 3rd modification of 1st and 2nd embodiment of this invention. It is the top view seen from the upper surface side of the differential microphone unit by the 4th modification of 1st and 2nd embodiment of this invention. It is sectional drawing of the differential microphone unit by the 4th modification of 1st and 2nd embodiment of this invention. It is sectional drawing of the differential microphone unit by the 5th modification of 1st and 2nd embodiment of this invention.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below with reference to the drawings.

(First embodiment)
With reference to FIGS. 1-8, the structure of the mobile telephone 200 provided with the differential microphone unit 100 by 1st Embodiment of this invention is demonstrated. The differential microphone unit 100 is an example of the “microphone unit” in the present invention, and the mobile phone 200 is an example of the “mobile device” in the present invention. Here, the differential microphone unit 100 of the present invention has two sound holes, and each of the sound pressures input to the two sound holes is supplied to the front and back surfaces of a vibration part (vibration plate) to be described later. introduce. The diaphragm vibrates according to the differential pressure of the sound pressure between the front and back, and outputs this vibration change as an electrical signal. The distances from the two sound holes to the diaphragm are substantially equal, and the delay difference is designed to be zero by equalizing the sound propagation time from the two sound holes to the diaphragm. The differential microphone unit 100 designed in this way is characterized by a large sensitivity attenuation characteristic with distance. A normal omnidirectional microphone has an attenuation factor of −20 dB / dec, whereas the differential microphone unit 100 has an attenuation factor of −40 dB / dec and a large attenuation factor. That is, it functions as a close-talking microphone that suppresses far-field noise and captures only close-in sounds. In order to maximize this performance, the acoustic transmission characteristics from the two sound holes to the diaphragm should be made equal as much as possible, and the balance from each of the two sound holes to the diaphragm should be balanced, It is necessary to propagate sound efficiently. If an acoustic leak occurs in one of these propagation paths or a leak occurs from one propagation path to the other, a balance shift or transmission loss occurs, and the above-mentioned excellent performance can be achieved. Disappear.

  As shown in FIG. 1, the mobile phone 200 according to the first embodiment of the present invention includes a mobile phone casing 1 and input key units 2 such as “0-9”, “*”, and “#”, An operation key unit 3 such as a menu button or a mail button, a display screen unit 4 including a liquid crystal display, a speaker 5, an antenna 6, and a differential microphone unit 100 are provided. The mobile phone case 1 is an example of the “product case” and the “portable device case” in the present invention. As shown in FIG. 2, the differential microphone unit 100 is provided on the back side of the mobile phone casing 1 so that the longitudinal direction of the differential microphone unit 100 is along the X direction.

  As shown in FIG. 3, the differential microphone unit 100 includes a substrate 10, a cover portion 20, and a gasket 30. The gasket 30 is an example of the “sealing member” in the present invention.

  As shown in FIG. 3, the substrate 10 is made of an insulating material such as glass epoxy having a thickness t1 of about 0.2 mm or more and about 0.8 mm or less. Further, the substrate 10 is provided with a MEMS (Micro Electro Mechanical System) chip 12 having a vibration part 11 that vibrates due to the sound pressure of sound input from the outside. In addition, a sound path 13 for guiding sound input from the outside to the surface of the vibration unit 11 on the Z1 direction side is formed on the substrate 10. Further, an electrical signal output IC 14 that is an integrated circuit for outputting an electrical signal based on the vibration of the vibration part 11 of the MEMS chip 12 is disposed in the vicinity of the MEMS chip 12. The MEMS chip 12 and the electric signal output IC 14 are electrically connected by the wiring 15a and the wiring 15b.

  Further, as shown in FIG. 5, the substrate 10 is formed with three through holes 17a, a through hole 17b, and a through hole 17c. Moreover, the wiring 18a, the wiring 18b, and the wiring 18c are embedded in the through-hole 17a, the through-hole 17b, and the through-hole 17c, respectively. Further, on the front surface (back surface) of the substrate 10 on the Z1 direction side, as shown in FIG. 7, three electrode portions 16a, 16b, and electrodes are connected to the wires 18a, 18b, and 18c, respectively. A portion 16c is formed. The three electrode portions 16a, the electrode portion 16b, and the electrode portion 16c are formed to supply electric power to the electric signal output IC 14, output an electric signal from the electric signal output IC 14, and perform GND connection, respectively.

  Further, as shown in FIG. 3, the cover portion 20 uses an adhesive layer (not shown) having a thickness of about 50 μm (about 0.05 mm) so as to cover the MEMS chip 12 and the electric signal output IC 14. Is adhered to the surface on the Z2 direction side. Moreover, the cover part 20 consists of heat resistant resin which has thickness t2 of about 0.6 mm or more and about 1.0 mm or less. In addition, the space surrounded by the cover 20 and the substrate 10 in which the MEMS chip 12 and the electric signal output IC 14 are accommodated is an acoustic path 21 for guiding sound from the outside to the surface on the Z2 direction side of the vibration part 11. Function.

  Here, in the first embodiment, as shown in FIGS. 4 and 5, a first recess 22 (second recess 23) having a rectangular cross section is formed on the surface of the cover portion 20 on the Z2 direction side. Yes. Further, the depth D1 of the inner bottom surface 22c (inner bottom surface 23c) of the first concave portion 22 (second concave portion 23) of the cover portion 20 is about 0.2 mm or more and about 2.8 mm or less. In addition, the 1st recessed part 22 (2nd recessed part 23) of the cover part 20 is formed so that it may have a rectangular shape (refer FIG. 5) seeing planarly. Moreover, the width W1 (refer FIG. 4) of the X direction of the 1st recessed part 22 (2nd recessed part 23) is about 1.1 mm.

  Moreover, the 1st recessed part 22 (2nd recessed part 23) is formed with the 1st cover part side sound hole 22a (2nd cover part side sound hole 23a) so that it may extend along a Z direction. The first cover portion side sound hole 22a (second cover portion side sound hole 23a) is formed in a long hole shape (an oblong shape) (see FIGS. 5 and 6) when seen in a plan view. Moreover, the hole width W2 (refer FIG. 4) of the X direction of the 1st cover part side sound hole 22a (2nd cover part side sound hole 23a) is about 0.2 mm or more and about 0.5 mm or less. Further, the width (thickness) W3 in the X direction of the first recess 22 between the inner side surface 22b of the first recess 22 and the first cover side sound hole 22a is about 0.3 mm or more and about 0.45 mm or less. is there. Further, the width (thickness) W3 in the X direction of the second recess 23 between the inner side surface 23b of the second recess 23 and the second cover portion side sound hole 23a is also about 0.3 mm or more and about 0.45 mm or less. is there.

  As shown in FIG. 6, the hole width W4 in the Y direction of the first cover part side sound hole 22a (second cover part side sound hole 23a) is about 1.5 mm or more and about 2.0 mm or less. Further, the width (thickness) W5 in the Y direction of the first recess 22 between the inner side surface 22b of the first recess 22 and the first cover side sound hole 22a is about 0.3 mm or more and about 0.45 mm or less. is there. Further, the width (thickness) W5 in the Y direction of the second recess 23 between the inner side surface 23b of the second recess 23 and the second cover portion side sound hole 23a is also about 0.3 mm or more and about 0.45 mm or less. is there.

  As shown in FIG. 3, the gasket 30 is made of an elastically deformable material (such as a rubber member) and is disposed on the surface of the cover portion 20. In the first embodiment, as shown in FIG. 4, the surface of the gasket 30 on the Z1 direction side protrudes in the Z1 direction and has a rectangular first section 31 (second protrusion 32). Is formed. Further, the protrusion height h1 of the surface 31b (surface 32b) of the first convex portion 31 (second convex portion 32) is about 0.2 mm or more and about 2.8 mm or less, and the first concave portion 22 ( It is substantially equal to the depth D1 (about 0.2 mm or more and about 2.8 mm or less) of the second recess 23). Moreover, the thickness t3 (refer FIG. 3) of the gasket 30 of the part in which the 1st convex part 31 (2nd convex part 32) of the gasket 30 is not formed is about 0.2 mm or more and about 3.0 mm or less. The surface 31 b of the first convex portion 31 is in contact with the inner bottom surface 22 c of the first concave portion 22, and the surface 32 b of the second convex portion 32 is in contact with the inner bottom surface 23 c of the second concave portion 23 on the Z2 direction side. In contact. Further, the width W6 in the X direction of the first convex portion 31 (second convex portion 32) is about 1.1 mm, and the width W1 in the X direction of the first concave portion 22 (second concave portion 23) (about 1.1 mm). ).

  While connecting with the surface 31b (surface 32b) of this 1st convex part 31 (2nd convex part 32) with the 1st cover part side sound hole 22a (2nd cover part side sound hole 23a) of the cover part 20, A first gasket side sound hole 31a (second gasket side sound hole 32a) is formed so as to extend along the Z direction. The first gasket side sound hole 31a is an example of the “first sealing member side sound hole” in the present invention, and the second gasket side sound hole 32a is the “second sealing member side sound hole” in the present invention. Is an example. Moreover, the 1st convex part 31 (2nd convex part 32) is formed so that the circumference | surroundings of the 1st gasket side sound hole 31a (2nd gasket side sound hole 32a) may be enclosed.

  The width W7 in the X direction of the first gasket side sound hole 31a (second gasket side sound hole 32a) is about 0.2 mm or more and about 0.5 mm or less, and the first cover part side sound hole 22a (second The X-direction hole width W2 (about 0.2 mm or more and about 0.5 mm or less) of the cover part side sound hole 23a) is substantially equal. Further, the first convex portion 31 between the outer side surface 31c (outer side surface 32c) of the first convex portion 31 (second convex portion 32) and the first gasket side sound hole 31a (second gasket side sound hole 32a). The width W8 in the X direction is about 0.3 mm or more and about 0.45 mm or less, and the inner side surface 22b (inner side surface 23b) of the first recess 22 (second recess 23) and the first cover side sound hole 22a (first It is substantially equal to the width (thickness) W3 in the X direction between the two cover side sound holes 23a).

  Further, as shown in FIG. 6, the Y-direction hole width W9 of the first gasket-side sound hole 31a (second gasket-side sound hole 32a) is about 1.5 mm or more and about 2.0 mm or less, and the first cover It is substantially equal to the hole width W4 in the Y direction of the part side sound hole 22a (second cover part side sound hole 23a).

  In addition, the first in the Y direction between the outer surface 31c (outer surface 32c) of the first convex portion 31 (second convex portion 32) and the first gasket side sound hole 31a (second gasket side sound hole 32a). The width W10 of the convex portion 31 (second convex portion 32) is not less than about 0.3 mm and not more than about 0.45 mm. That is, the first convex portion 31 between the outer side surface 31c (outer side surface 32c) of the first convex portion 31 (second convex portion 32) and the first gasket side sound hole 31a (second gasket side sound hole 32a). The width W10 in the Y direction of the (second convex portion 32) is equal to the inner side surface 22b (inner side surface 23b) of the first concave portion 22 (second concave portion 23) and the first cover portion side sound hole 22a (second cover portion side). It is substantially equal to the width (thickness) W5 in the Y direction of the first recess 22 (second recess 23) between the sound hole 23a).

  Moreover, in 1st Embodiment, as shown in FIG. 4, the 1st convex part 31 (2nd convex part 32) of the gasket 30 is press-fitted in the 1st recessed part 22 (2nd recessed part 23) of the cover part 20. As shown in FIG. Yes. As a result, the inner side surface 22b (inner side surface 23b) of the first concave portion 22 (second concave portion 23) of the cover portion 20 and the outer side surface 31c (outer side surface) of the first convex portion 31 (second convex portion 32) of the gasket 30 are obtained. 32c). Further, the inner bottom surface 22c (inner bottom surface 23c) of the first concave portion 22 (second concave portion 23) of the cover portion 20, and the surface 31b (front surface 32b) of the first convex portion 31 (second convex portion 32) of the gasket 30 Are configured to be in close contact with each other. As a result, the first concave portion 22 (second concave portion 23) of the cover portion 20 and the first convex portion 31 (second convex portion 32) of the gasket 30 are configured to be fixedly engaged. Thereby, the inner surface of the first cover side sound hole 22a (second cover side sound hole 23a) and the inner surface of the first gasket side sound hole 31a (second gasket side sound hole 32a) are flush with each other. It is configured to be aligned.

  Further, as shown in FIG. 8, the sound (sound) from the outside passes through the first gasket side sound hole 31 a, the first cover part side sound hole 22 a, and the sound path 13 in the Z1 direction of the vibration part 11. It is configured to reach the side surface. In addition, the vibration portion 11 is provided via the second gasket side sound hole 32a, the second cover portion side sound hole 23a, and the space (sound path 21) in which the MEMS chip 12 of the cover portion 20 and the electric signal output IC 14 are accommodated. The sound reaches the surface on the Z2 direction side. Thus, the differential microphone unit 100 that detects the differential pressure between the sound pressure of the sound that has reached the surface on the Z1 direction side of the vibration unit 11 and the sound pressure of the sound that has reached the surface on the Z2 direction side of the vibration unit 11 is provided. Composed.

  As shown in FIG. 3, the differential microphone unit 100 is disposed on the surface on the Z1 direction side of the mobile phone casing 1, and the gasket 30 includes the cover 20 and the mobile phone casing 1. It arrange | positions so that between may be sealed. The cellular phone casing 1 includes a first casing sound hole 1a and a position overlapping the first gasket side sound hole 31a and the second gasket side sound hole 32a of the gasket 30 in plan view, respectively. A second housing part sound hole 1b is formed. Further, the width W11 in the X direction of the first housing portion sound hole 1a and the second housing portion sound hole 1b is about 0.7 mm.

  In the first embodiment, as described above, the first concave portion 22 (second concave portion 23) of the cover portion 20 and the first convex portion 31 (second convex portion 32) of the gasket 30 are fixedly engaged. Thus, unlike the case where the cover portion 20 and the gasket 30 are relatively movable, the engagement between the first concave portion 22 (second concave portion 23) and the first convex portion 31 (second convex portion 32) is released. Since it is difficult, it can suppress more reliably that the acoustic leak from between the cover part 20 and the gasket 30 generate | occur | produces. Further, the inner side surface 22b (inner side surface 23b) of the first concave portion 22 (second concave portion 23) of the cover portion 20, and the outer side surface 31c (outer side surface 32c) of the first convex portion 31 (second convex portion 32) of the gasket 30. ), For example, even when the cover portion 20 is displaced in the Z direction with respect to the gasket 30, the amount of displacement is the depth D1 (first protrusion) of the first recess 22 (second recess 23). Within the range of the height h1) of the portion 31 (second convex portion 32), the inner side surface 22b (inner side surface 23b) of the first concave portion 22 (second concave portion 23) and the first convex portion 31 (second convex portion). 32) can be maintained in close contact with the outer side surface 31c (outer side surface 32c), and this also more reliably suppresses the occurrence of acoustic leakage between the cover portion 20 and the gasket 30. be able to. In addition, for example, unlike the case where a convex portion is formed in the cover portion and a concave portion is formed in the gasket, the thickness of the gasket can be reduced, so that the thickness of the differential microphone unit 100 can be reduced (thinned). it can.

  In the first embodiment, as described above, the inner side surface 22b (inner side surface 23b) of the first concave portion 22 (second concave portion 23) of the cover portion 20 and the first convex portion 31 (second convex portion of the gasket 30). 32) and the inner bottom surface 22c (inner bottom surface 23c) of the first concave portion 22 (second concave portion 23) of the cover portion 20 and the first convex portion 31 ( In a state where the surface 31b (surface 32b) of the second convex portion 32) is in close contact, the first concave portion 22 (second concave portion 23) of the cover portion 20 and the first convex portion 31 (second convex portion 32) of the gasket 30. Are fixedly engaged with each other. As a result, the inner side surface 22b (inner side surface 23b) of the first concave portion 22 (second concave portion 23) of the cover portion 20 and the outer side surface 31c (outer side surface 32c) of the first convex portion 31 (second convex portion 32) of the gasket 30 are obtained. ), And the inner bottom surface 22c (inner bottom surface 23c) of the first concave portion 22 (second concave portion 23) of the cover portion 20 and the surface 31b (first convex portion 32) of the gasket 30 ( Since both can be brought into close contact with the surface 32b) and kept in a fixedly engaged state, the occurrence of acoustic leakage can be further reliably suppressed.

  In the first embodiment, as described above, the first convex portion 31 (second convex portion 32) of the gasket 30 is press-fitted into the first concave portion 22 (second concave portion 23) of the cover portion 20. The inner side surface 22b (inner side surface 23b) of the first concave portion 22 (second concave portion 23) of the portion 20 and the outer side surface 31c (outer side surface 32c) of the first convex portion 31 (second convex portion 32) of the gasket 30 are brought into close contact with each other. In addition, the first concave portion 22 (second concave portion 23) of the cover portion 20 and the first convex portion 31 (second convex portion 32) of the gasket 30 are fixedly engaged. Thereby, unlike the case where the 1st convex part 31 (2nd convex part 32) of the gasket 30 and the 1st recessed part 22 (2nd recessed part 23) of the cover part 20 are contacting lightly, the 1st of the gasket 30 is shown. Since the convex part 31 (second convex part 32) and the first concave part 22 (second concave part 23) of the cover part 20 can be firmly fixed, the first convex part 31 (second convex part 32) and The adhesion (air tightness) between the first concave portion 22 (second concave portion 23) can be further improved, and the first convex portion 31 (second convex portion 32) and the first concave portion 22 (second concave portion). 23) can be effectively prevented from being disengaged.

  In the first embodiment, as described above, the sound reaches the Z1 direction side of the vibration part 11 via the first gasket side sound hole 31a and the first cover part side sound hole 22a, and the second gasket side When the sound reaches the Z2 direction side of the vibration part 11 through the sound hole 32a and the second cover part side sound hole 23a, the sound pressure of the sound reaching the Z1 direction side of the vibration part 11 and the vibration part 11 A differential pressure from the sound pressure of the sound reaching the Z2 direction side is detected. As a result, sound is generated both between the first concave portion 22 of the cover portion 20 and the first convex portion 31 of the gasket 30 and between the second concave portion 23 of the cover portion 20 and the second convex portion 32 of the gasket 30. It is possible to more reliably suppress the occurrence of leak. Thereby, the sound pressure input from the first cover part side sound hole 22a and the sound pressure input from the second cover part side sound hole 23a are transmitted to the front surface and the back surface of the vibration part 11, respectively, and the difference is obtained. The pressure can be detected accurately. As a result, it is possible to maximize the performance of suppressing far-field noise.

  In the first embodiment, as described above, the depth D1 of the first concave portion 22 (second concave portion 23) of the cover portion 20 is set to the height of the first convex portion 31 (second convex portion 32) of the gasket 30. It is made substantially equal to h1. As a result, the inner side surface 22b (inner side surface 23b) of the first concave portion 22 (second concave portion 23) of the cover portion 20 and the outer side surface 31c (outer side surface) of the first convex portion 31 (second convex portion 32) of the gasket 30 are obtained. 32c) and the inner bottom surface of the first concave portion 22 (second concave portion 23) of the cover portion 20 and the first convex portion 31 (second convex portion 32) in the projecting direction (Z1 direction). 22c (inner bottom surface 23c) and the surface 31b (surface 32b) of the 1st convex part 31 (2nd convex part 32) of the gasket 30 can be made to contact (contact | adhere). As a result, the inner side surface 22b (inner side surface 23b) of the first concave portion 22 (second concave portion 23) of the cover portion 20 and the outer side surface 31c (outer side surface) of the first convex portion 31 (second convex portion 32) of the gasket 30 are obtained. 32c) can be further improved.

  In the first embodiment, as described above, the gasket 30 is disposed so as to seal between the back side of the mobile phone casing 1 in which the differential microphone unit 100 is housed and the cover 20. As a result, the gasket 30 can suppress the occurrence of acoustic leakage from between the back side of the mobile phone casing 1 in which the differential microphone unit 100 is housed and the cover 20.

(First modification of the first embodiment)
Next, a first modification of the first embodiment of the present invention will be described with reference to FIGS. 9 and 10. Unlike the first embodiment, the differential microphone unit 101 according to the first modification of the first embodiment includes a gasket having a convex section having a rectangular cross section. The tapered convex section having a tapered cross section. Is provided with a gasket formed. The differential microphone unit 101 is an example of the “microphone unit” in the present invention.

  As shown in FIG. 10, the differential microphone unit 101 according to the first modification of the first embodiment has a first recess 22 (second recess) having a rectangular cross section on the surface of the cover portion 20 on the Z2 direction side. 23) is formed. In addition, on the surface of the gasket 301 on the Z1 direction side, a tapered first convex portion 302 (second convex portion 303) that protrudes in the Z1 direction and has a tapered cross section is formed. Further, in a state before the first convex portion 302 (second convex portion 303) of the gasket 301 is press-fitted into the first concave portion 22 (second concave portion 23) of the cover portion 20, the first concave portion 22 of the cover portion 20. The width W12 of the open end of the (second concave portion 23) is smaller than the width W13 of the root portion of the first convex portion 302 (second convex portion 303) of the gasket 301.

  And when the 1st convex part 302 (2nd convex part 303) of the gasket 301 is press-fit in the 1st recessed part 22 (2nd recessed part 23) of the cover part 20, the 1st convex part 302 (2nd 2nd of the gasket 301). The tapered portion 302a (tapered portion 303a) of the convex portion 303) is configured to be elastically deformed in the pushing direction by contacting the opening end of the first concave portion 22 (second concave portion 23) of the cover portion 20. Yes.

  Then, as shown in FIG. 9, when the first recess 22 (second recess 23) of the cover portion 20 is press-fitted, the inner side surface 22 b (inner side) of the first recess 22 (second recess 23) of the cover portion 20. The side surface 23b and the taper portion 302a (taper portion 303a) of the first convex portion 302 (second convex portion 303) of the gasket 301 are in close contact with each other. Further, the inner bottom surface 22c (inner bottom surface 23c) of the first concave portion 22 (second concave portion 23) of the cover portion 20, and the surface 302b (front surface 303b) of the first convex portion 302 (second convex portion 303) of the gasket 301, Is in close contact. Accordingly, the first concave portion 22 (second concave portion 23) of the cover portion 20 and the first convex portion 302 (second convex portion 303) of the gasket 301 are configured to be fixedly engaged.

  In addition, the other structure of the 1st modification of 1st Embodiment is the same as that of 1st Embodiment mentioned above.

  In the first modification of the first embodiment, as described above, the width W12 of the opening end of the first recess 22 (second recess 23) of the cover 20 is set to the first protrusion 302 (second protrusion) of the gasket 301. By making the width W13 smaller than the width W13 of the base portion of the portion 303), the first concave portion 22 (second concave portion 23) having a substantially rectangular shape of the cover portion 20 and the first convex portion 302 having a tapered shape of the gasket 301 (second portion). When the convex portion 303) is fitted together, the tapered portion 302a (tapered portion 303a) of the first convex portion 302 (second convex portion 303) of the gasket 301 is elastically deformed and pushed inward. As a result, a biasing force acts on the inner side surface 22b (inner side surface 23b) of the first concave portion 22 (second concave portion 23) in the first concave portion 22 (second concave portion 23) of the cover portion 20. Adhesion between the tapered portion 302a (tapered portion 303a) of the first convex portion 302 (second convex portion 303) and the inner side surface 22b (inner side surface 23b) of the first concave portion 22 (second concave portion 23) of the cover portion 20. The property (airtightness) can be further improved.

  The remaining effects of the first modification of the first embodiment are similar to those of the aforementioned first embodiment.

(Second modification of the first embodiment)
Next, a second modification of the first embodiment of the present invention will be described with reference to FIG. 11 and FIG. In the differential microphone unit 102 according to the second modification of the first embodiment, unlike the first embodiment including a gasket having a convex portion having a rectangular cross section, the outer surface of the convex portion has a concave and convex shape. A gasket having a stepped portion is provided. The differential microphone unit 102 is an example of the “microphone unit” in the present invention.

  As shown in FIG. 12, the differential microphone unit 102 according to the second modification of the first embodiment has a first recess 22 having a width (opening end) of W14 on the surface of the cover portion 20 on the Z2 direction side. (Second recess 23) is formed. Further, the gasket 130 is formed with a first convex portion 131 (second convex portion 132) that protrudes in the Z1 direction and has a width of W15. In addition, an uneven step part 131b (step part 132b) is formed at the end of the outer surface 131a (outer surface 132a) of the first protrusion 131 (second protrusion 132) on the Z2 direction side. The step 131b (step 132b) is formed in a cut shape so as to be recessed in the X direction. The width W14 of the first concave portion 22 (second concave portion 23) is smaller than the width W15 of the first convex portion 131 (second convex portion 132).

  As shown in FIG. 11, the first convex portion 131 (second convex portion 132) of the gasket 130 is press-fitted into the first concave portion 22 (second concave portion 23) of the cover portion 20. Accordingly, the inner side surface 22b (inner side surface 23b) of the first concave portion 22 (second concave portion 23) of the cover portion 20 and the outer side surface 131a (outer side surface) of the first convex portion 131 (second convex portion 132) of the gasket 130 are obtained. 132a). At this time, the outer side surface 131a (outer side surface 132a) of the first convex portion 131 (second convex portion 132) is moved in the X direction by the inner side surface 22b (inner side surface 23b) of the first concave portion 22 (second concave portion 23). Engaged to be pushed. Further, the inner bottom surface 22c (inner bottom surface 23c) of the first concave portion 22 (second concave portion 23) of the cover portion 20, and the surface 131c (front surface 132c) of the first convex portion 131 (second convex portion 132) of the gasket 130, Is in close contact. As a result, the first concave portion 22 (second concave portion 23) of the cover portion 20 and the first convex portion 131 (second convex portion 132) of the gasket 130 are configured to be fixedly engaged.

  In addition, the other structure of the 2nd modification of 1st Embodiment is the same as that of 1st Embodiment mentioned above.

  In the second modification of the first embodiment, as described above, the outer side surface 131a (outer side surface 132a) of the first convex portion 131 (second convex portion 132) formed on the gasket 130 is formed in an uneven shape. Thus, the inner side surface 22b (inner side surface 23b) of the cover portion 20 is brought into close contact with the concave and convex shape formed on the outer side surface 131a (outer side surface 132a) of the first convex portion 131 (second convex portion 132) of the gasket 130. Therefore, the engagement state between the first concave portion 22 (second concave portion 23) of the cover portion 20 and the first convex portion 131 (second convex portion 132) of the gasket 130 can be made more difficult to disengage.

  The remaining effects of the second modification of the first embodiment are similar to those of the aforementioned first embodiment.

(Third Modification of First Embodiment)
Next, with reference to FIGS. 13 and 14, a third modification of the first embodiment of the present invention will be described. In the differential microphone unit 103 according to the third modified example of the first embodiment, unlike the first embodiment including a cover portion in which a concave portion having a rectangular cross section is formed, an uneven shape step is formed on the inner surface of the concave portion. The cover part in which the part was formed is provided. The differential microphone unit 103 is an example of the “microphone unit” in the present invention.

  In the differential microphone unit 103 according to the third modification of the first embodiment, as shown in FIG. 14, a first recess 221 having a width W16 (open end) is provided on the surface of the cover portion 220 on the Z2 direction side. (Second recess 222) is formed. A stepped portion 221b (stepped portion 222b) is formed on the inner side surface 221a (inner side surface 222a) of the first recessed portion 221 (second recessed portion 222). The gasket 30 is formed with a first convex portion 31 (second convex portion 32) that protrudes in the Z1 direction and has a width of W17. Further, the outer surface 31c (outer surface 32c) of the gasket 30 is formed in a rectangular shape. Note that the width W16 of the first concave portion 221 (second concave portion 222) is smaller than the width W17 of the first convex portion 31 (second convex portion 32).

  As shown in FIG. 13, the first convex portion 31 (second convex portion 32) of the gasket 30 is press-fitted into the first concave portion 221 (second concave portion 222) of the cover portion 220. Accordingly, the inner side surface 221a (inner side surface 222a) of the first concave portion 221 (second concave portion 222) of the cover portion 220 and the outer side surface 31c (outer side surface) of the first convex portion 31 (second convex portion 32) of the gasket 30 are obtained. 32c). Further, the inner bottom surface 221c (inner bottom surface 222c) of the first concave portion 221 (second concave portion 222) of the cover portion 220, and the surface 31b (front surface 32b) of the first convex portion 31 (second convex portion 32) of the gasket 30 Is in close contact. At this time, the end portion in the Z1 direction of the first convex portion 31 (second convex portion 32) is engaged so as to bite into the step portion 221b (step portion 222b) of the first concave portion 221 (second concave portion 222). . As a result, the first concave portion 221 (second concave portion 222) of the cover portion 220 and the first convex portion 31 (second convex portion 32) of the gasket 30 are configured to be fixedly engaged.

  In addition, the other structure of the 3rd modification of 1st Embodiment is the same as that of 1st Embodiment mentioned above.

  In the third modification of the first embodiment, as described above, the inner side surface 221a (inner side surface 222a) of the first concave portion 221 (second concave portion 222) formed in the cover portion 220 is formed in an uneven shape. Accordingly, the concave and convex shape formed on the inner side surface 221a (inner side surface 222a) of the first concave portion 221 (second concave portion 222) of the cover portion 220 brings the outer surface 31c (outer surface 32c) of the gasket 30 into close contact, Since the end portion in the Z1 direction of the first convex portion 31 (second convex portion 32) can be bitten into the step portion 221b (step portion 222b) of the first concave portion 221 (second concave portion 222), the cover portion 220 is obtained. The engagement state between the first concave portion 221 (second concave portion 222) and the first convex portion 31 (second convex portion 32) of the gasket 30 can be made more difficult to disengage. Further, the cover 220 and the gasket 30 are engaged with each other by forming a notched step 221b (step 222b) in the first recess 221 (second recess 222) of the cover 220 so as to be recessed in the X direction. When mating, the opening end of the first concave portion 221 (second concave portion 222) of the cover portion 220 can be easily expanded in the X direction, so that the cover portion 220 and the gasket 30 can be easily fitted (easily engaged). )can do.

  The remaining effects of the third modification of the first embodiment are similar to those of the aforementioned first embodiment.

(Fourth modification of the first embodiment)
Next, a fourth modification of the first embodiment of the present invention will be described with reference to FIGS. 15 and 16. In the differential microphone unit 104 according to the fourth modification of the first embodiment, unlike the first embodiment including a gasket having a convex portion having a rectangular cross section, the cross section has an uneven shape (wave shape). A gasket having a convex portion is provided. The differential microphone unit 104 is an example of the “microphone unit” in the present invention.

  In the differential microphone unit 104 according to the fourth modification of the first embodiment, as shown in FIG. 16, the surface of the cover portion 20 on the Z2 direction side has a rectangular shape having a width W18 (open end). One recess 22 (second recess 23) is formed. Moreover, the 1st convex part 231 (2nd convex part 232) is formed in the Z1 direction side surface of the gasket 230 so that it may protrude in Z1 direction. Further, the outer surface 231a (outer surface 232a) of the first convex portion 231 (second convex portion 232) is formed in an uneven shape (wave shape) including the tip portion 231c (232c) and the root portion 231d (232d). Yes. The width (interval) in the X direction from one tip portion 231c (232c) of the first convex portion 231 (second convex portion 232) to the other tip portion 231c (232c) is W19. Further, the width (interval) in the X direction from one root portion 231d (232d) of the first convex portion 231 (second convex portion 232) to the other root portion 231d (232d) is W20. The width W18 of the first concave portion 22 (second concave portion 23) is smaller than the width W19 of the tip portion 231c (232c) of the first convex portion 231 (second convex portion 232), and the first convex portion 231 is provided. It is larger than the width W20 of the root portion 231d (232d) of the (second convex portion 232).

  As shown in FIG. 15, the first convex portion 231 (second convex portion 232) of the gasket 230 is press-fitted into the first concave portion 22 (second concave portion 23) of the cover portion 20. As a result, the inner side surface 22b (inner side surface 23b) of the first concave portion 22 (second concave portion 23) of the cover portion 20 and the outer side surface 231a (outer side surface) of the first convex portion 231 (second convex portion 232) of the gasket 230 are obtained. 232a) are in close contact with each other. Specifically, the tip 231c (232c) of the first convex portion 231 (second convex portion 232) presses the inner side surface 22b (inner side surface 23b) of the first concave portion 22 (second concave portion 23). The tip portion 231c (232c) is elastically deformed and crushed along the shape of the inner side surface 22b (inner side surface 23b) of the first concave portion 22 (second concave portion 23). (2) the inner surface 22b (inner surface 23b) of the recess 23). Further, there is a gap between the inner side surface 22b (inner side surface 23b) of the first concave portion 22 (second concave portion 23) and the root portion 231d (232d) of the first convex portion 231 (second convex portion 232). it can. Further, the inner bottom surface 22c (inner bottom surface 23c) of the first concave portion 22 (second concave portion 23) of the cover portion 20, and the surface 231b (front surface 232b) of the first convex portion 231 (second convex portion 232) of the gasket 230, Are in close contact. As described above, the first recess 22 (second recess 23) of the cover portion 20 and the first protrusion 231 (second protrusion 232) of the gasket 230 are configured to be fixedly engaged.

  The remaining configuration of the fourth modification example of the first embodiment is similar to that of the aforementioned first embodiment.

  In the fourth modification of the first embodiment, as described above, the front end portion 231c (232c) of the outer side surface 231a (outer side surface 232a) of the first convex portion 231 (second convex portion 232) of the gasket 230 is covered. Inside the first recess 22 (second recess 23) of the cover portion 20 in an elastically deformed state along the shape of the inner side surface 22b (inner side surface 23b) of the first recess 22 (second recess 23) of the portion 20 The side surface 22b (inner side surface 23b) is engaged. As a result, the first recess 22 (second recess 23) of the cover portion 20 is changed from the outer surface 231a (outer surface 232a) of the first projection 231 (second projection 232) to the first recess 22 (second recess). 23), the urging force (pressing force) acts toward the outer surface 231a (outer surface 232a) of the first convex portion 231 (second convex portion 232) of the gasket 230 and the first concave portion 22 ( The adhesiveness (air tightness) between the inner surface 22b (the inner surface 23b) of the second recess 23) can be improved more effectively, and the uneven shape of the first protrusion 231 (the second protrusion 232). Thereby, the engagement state of the 1st recessed part 22 (2nd recessed part 23) and the 1st convex part 231 (2nd convex part 232) can be made harder to remove | deviate.

  The remaining effects of the fourth modification example of the first embodiment are similar to those of the aforementioned first embodiment.

(Fifth Modification of First Embodiment)
Next, a fifth modification of the first embodiment of the present invention will be described with reference to FIGS. In the differential microphone unit 105 according to the fifth modification of the first embodiment, the cross section has an uneven shape (wave shape), unlike the first embodiment provided with a cover portion in which a concave portion having a rectangular cross section is formed. The cover part in which the recessed part was formed is provided. The differential microphone unit 105 is an example of the “microphone unit” in the present invention.

  In the differential microphone unit 105 according to the fifth modification of the first embodiment, as shown in FIG. 18, a first recess 321 (second recess 322) is formed on the surface of the cover portion 320 on the Z2 direction side. ing. The inner side surface 321a (inner side surface 322a) of the first concave portion 321 (second concave portion 322) is formed in an uneven shape (wave shape) including a tip end portion 321c (322c) and a root portion 321d (322d). The width (interval) in the X direction of the tip portion 321c (322c) of the first recess 321 (second recess 322) facing each other is W21. Further, the width (interval) in the X direction of the root portion 321d (322d) of the first recess 321 (second recess 322) facing each other is W22. Further, the gasket 30 is formed with a first convex portion 31 (second convex portion 32) that protrudes in the Z1 direction and has a width of W23. The width W23 of the first convex portion 31 (second convex portion 32) is larger than the width W21 of the tip portion 321c (322c) of the first concave portion 321 (second concave portion 322), and the first concave portion 321 ( It is smaller than the width W22 of the root portion 321d (322d) of the second recess 322).

  As shown in FIG. 17, the first convex portion 31 (second convex portion 32) of the gasket 30 is press-fitted into the first concave portion 321 (second concave portion 322) of the cover portion 320. Accordingly, the inner side surface 321a (inner side surface 322a) of the first concave portion 321 (second concave portion 322) of the cover portion 320 and the outer side surface 31c (outer side surface) of the first convex portion 31 (second convex portion 32) of the gasket 30 are obtained. 32c) are in close contact with each other. Specifically, the outer side surface 31c (outer side surface 32c) of the first convex portion 31 (second convex portion 32) pushes the tip portion 321c (322c) of the first concave portion 321 (second concave portion 322). Become. That is, the outer surface 31c (outer surface 32c) of the first convex portion 31 (second convex portion 32) is elastically deformed so as to follow the shape of the tip portion 321c (322c) of the first concave portion 321 (second concave portion 322). Then, in the state of being crushed, it is in close contact with the inner surface 321a (inner surface 322a) of the first recess 321 (second recess 322). At this time, between the base part 321d (root part 322d) of the first concave part 321 (second concave part 322) and the outer side surface 31c (outer side face 32c) of the first convex part 31 (second convex part 32). , There is a gap. Further, the inner bottom surface 321b (inner bottom surface 322b) of the first concave portion 321 (second concave portion 322) of the cover portion 320, and the surface 31b (front surface 32b) of the first convex portion 31 (second convex portion 32) of the gasket 30 Are in close contact. Thus, the first concave portion 321 (second concave portion 322) of the cover portion 320 and the first convex portion 31 (second convex portion 32) of the gasket 30 are configured to be fixedly engaged.

  The remaining configuration of the fifth modification example of the first embodiment is similar to that of the aforementioned first embodiment.

  In the fifth modification of the first embodiment, as described above, the outer side surface 31c (outer side surface 32c) of the first convex portion 31 (second convex portion 32) of the gasket 30 is replaced with the first concave portion 321 of the cover portion 320. Inside the first recess 321 (second recess 322) of the cover 320 in a state of being elastically deformed so as to follow the shape of the tip 321c (322c) of the inner side 321a (inner side 322a) of the (second recess 322). The side surface 321a (inner side surface 322a) is engaged. As a result, the first recess 321 (second recess 322) of the cover portion 320 is changed from the outer surface 31c (outer surface 32c) of the first projection 31 (second projection 32) to the first recess 321 (second recess). 322), an urging force (pressing force) acts on the outer surface 31c (outer surface 32c) of the first protrusion 31 (second protrusion 32) of the gasket 30 and the first recess 321 ( The adhesion (air tightness) between the inner surface 321a (the inner surface 322a) of the second recess 322) can be improved more effectively, and the uneven shape of the first recess 321 (the second recess 322) The engagement state between the first concave portion 321 (second concave portion 322) and the first convex portion 31 (second convex portion 32) can be made more difficult to disengage.

  The effects of the fifth modification of the first embodiment are the same as those of the first embodiment described above.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. In the differential microphone unit 106 according to the second embodiment, unlike the first embodiment in which the gasket 30 is disposed on the surface on the Z2 direction side of the cover portion 20, the Z2 direction side of the cover portion 20 is illustrated. The gasket 30 is disposed on the surface via the conductive shield member 40. The differential microphone unit 106 is an example of the “microphone unit” in the present invention.

  In the differential microphone unit 106 according to the second embodiment of the present invention, as illustrated in FIG. 19, the gasket 30 is disposed on the surface of the cover portion 20 on the Z2 direction side via the conductive shield member 40. Yes. The shield member 40 is formed with a first opening 40a (second opening 40b) for allowing the first protrusion 31 (second protrusion 32) of the gasket 30 to escape.

  Further, the thickness t4 of the shield member 40 is about 0.1 mm or less. That is, the protrusion height h1 (about 0.2 mm or more and about 2.8 mm or less) of the first protrusion 31 (second protrusion 32) of the gasket 30 is formed larger than the thickness t4 of the shield member 40.

  In addition, the other structure of 2nd Embodiment is the same as that of 1st Embodiment mentioned above.

  In 2nd Embodiment, by making the protrusion height h1 of the 1st convex part 31 (2nd convex part 32) of the gasket 30 larger than the thickness t4 of the shield member 40 as mentioned above, by the shield member 40, The outer surface 31c (outer surface 32c) of the portion of the first protrusion 31 (second protrusion 32) of the gasket 30 protruding from the shield member 40 and the first recess 22 while removing noise such as electromagnetic waves. Occurrence (adhesion) of the (second recess 23) with the inner side surface 22b (inner side surface 23b) can easily suppress the occurrence of acoustic leak.

  The remaining effects of the second embodiment are similar to those of the aforementioned first embodiment.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and further includes all modifications within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the first and second embodiments, the mobile phone is shown as an example of the mobile device, but the present invention is not limited to this. For example, the present invention can be applied to a portable device such as a PDA having a differential microphone unit or a portable game machine.

  In the first and second embodiments, an example in which two concave portions are formed in the cover portion and two convex portions are formed in the gasket has been described. However, the present invention is not limited to this. For example, one concave portion may be formed in the cover portion, one convex portion may be formed in the gasket, three or more concave portions may be formed in the cover portion, and three or more convex portions may be formed in the gasket. May be.

  Moreover, in the said 1st and 2nd embodiment, although the recessed part (projection part of a gasket) of a cover part was seen in planar view, the example formed in a rectangular shape was shown, However, This invention is not limited to this. For example, like the differential microphone unit 107 of the first modified example shown in FIG. 20, the concave portion 107a (the convex portion 107b of the gasket) of the cover portion is formed in a long hole shape (long round shape) when seen in a plan view. May be. The differential microphone unit 107 is an example of the “microphone unit” in the present invention.

  Further, in the first and second embodiments, the concave portion of the cover portion (the convex portion of the gasket) is formed in a rectangular shape in plan view, and the cover portion side sound hole (gasket side sound hole) is long. Although the example which forms in a hole shape (long round shape) was shown, this invention is not restricted to this. For example, as in the differential microphone unit 108 of the second modification shown in FIG. 21, the concave portion 108a (the convex portion 108b of the gasket) of the cover portion is formed in a square shape when seen in a plan view, and the cover portion side The sound hole 108c (gasket side sound hole 108d) may be formed in a perfect circle shape. The width W24 of the cover portion side sound hole 108c (gasket side sound hole 108d) may be formed to be about 0.5 mm or more and about 1.0 mm or less. The differential microphone unit 108 is an example of the “microphone unit” in the present invention.

  Further, in the first and second embodiments, the concave portion of the cover portion (the convex portion of the gasket) is formed in a rectangular shape in plan view, and the cover portion side sound hole (gasket side sound hole) is long. Although the example which forms in a hole shape (long round shape) was shown, this invention is not restricted to this. For example, as in the differential microphone unit 109 of the third modified example shown in FIG. 22, the concave portion 109a (the convex portion 109b of the gasket) of the cover portion is formed in a perfect circle shape in plan view, and the cover portion The side sound hole 109c (gasket side sound hole 109d) may be formed in a perfect circle shape. The width W25 of the cover part side sound hole 109c (gasket side sound hole 109d) is preferably about 0.5 mm or more and about 1.0 mm or less. Moreover, you may make the recessed part (the convex part of a gasket) and the cover part side sound hole (gasket side sound hole) of a cover part into shapes other than a perfect circle shape (for example, elliptical shape). The differential microphone unit 109 is an example of the “microphone unit” in the present invention.

  In the first and second embodiments, the example in which the MEMS chip 12 and the electric signal output IC 14 are electrically connected by wiring is shown, but the present invention is not limited to this. For example, like the differential microphone unit 110 of the 4th modification shown in FIG. 23 and FIG. 24, you may electrically connect by a flip chip. Specifically, the MEMS chip 12 and the electric signal output IC 14 are electrically connected by wirings 110 a and 110 b formed on the surface of the substrate 10. The electrical signal output IC 14 is electrically connected to the wirings 110 c, 110 d and 110 e provided on the surface of the substrate 10. The differential microphone unit 110 is an example of the “microphone unit” in the present invention.

  In the first and second embodiments, the example in which the differential microphone unit is configured by using one substrate 10 is shown, but the present invention is not limited to this. For example, like the differential microphone unit 111 of the fifth modification shown in FIG. 25, the differential microphone unit 111 may be configured using two substrates 10a and 10b. The differential microphone unit 111 is an example of the “microphone unit” in the present invention.

1 Mobile phone housing (product housing) (mobile device housing)
10, 10a, 10b Substrate 11 Vibrating portion 20, 120, 220, 320 Cover portion 22, 121, 221, 321 First recess (recess)
22a 1st cover part side sound hole (cover part side sound hole)
22b, 23b, 221a, 222a, 321a, 322a Inner side surface 22c, 23c, 121b, 122b, 221c, 222c, 321b, 322b Inner bottom surface 23, 122, 222, 322 Second recess (recess)
23a Second cover side sound hole (cover side sound hole)
30, 130, 230 Gasket (sealing member)
31, 131, 231 First convex portion (convex portion)
31a 1st gasket side sound hole (1st sealing member side sound hole) (sealing member side sound hole)
31b, 32b, 131c, 132c, 231b, 232b Surface 31c, 32c, 131a, 132a, 231a, 232a Outer surface 32, 132, 232 Second convex portion (convex portion)
32a Second gasket side sound hole (second sealing member side sound hole) (sealing member side sound hole)
40 Shield members 100 to 111 Differential microphone unit (microphone unit)
200 Mobile phone (mobile device)

Claims (12)

A substrate provided with a vibrating portion that vibrates by sound pressure;
A cover part disposed on the substrate so as to cover the vibration part;
A sealing member disposed on the surface of the cover part,
The sealing member includes a sealing member side sound hole, and a convex portion that surrounds the periphery of the sealing member side sound hole and protrudes from the surface of the sealing member to the cover portion side,
The cover part includes a cover part side sound hole formed so as to be connected to the sealing member side sound hole of the sealing member, and a concave part disposed at a position corresponding to the convex part of the sealing member. Including
At least the inner surface of the concave portion of the cover portion and the outer surface of the convex portion of the sealing member are in close contact, and the concave portion of the cover portion and the convex portion of the sealing member are fixedly engaged. A microphone unit.   The inner surface of the concave portion of the cover portion and the outer surface of the convex portion of the sealing member are in close contact, and the inner bottom surface of the concave portion of the cover portion on the sealing member side and the convex portion of the sealing member The microphone unit according to claim 1, wherein the concave portion of the cover portion and the convex portion of the sealing member are fixedly engaged with each other in a state where the surface is in close contact.   When the convex portion of the sealing member is press-fitted into the concave portion of the cover portion, at least the inner surface of the concave portion of the cover portion and the outer surface of the convex portion of the sealing member are in close contact with each other. The microphone unit according to claim 1 or 2, wherein the concave portion and the convex portion of the sealing member are fixedly engaged. The sealing member side sound hole of the sealing member includes a first sealing member side sound hole and a second sealing member side sound hole,
The convex part of the sealing member surrounds the periphery of the first sealing member side sound hole, and projects from the surface of the sealing member to the cover part side, and the second sealing member A second convex portion surrounding the side sound hole and projecting from the surface of the sealing member toward the cover portion,
The cover part side sound hole of the cover part is connected to the first cover part side sound hole formed to be connected to the first sealing member side sound hole and the second sealing member side sound hole. A second cover part side sound hole formed in
The concave portion of the cover portion includes a first concave portion disposed at a position corresponding to the first convex portion of the sealing member, and a second concave portion disposed at a position corresponding to the second convex portion of the sealing member. Including
The sound reaches one side of the vibrating part via the first sealing member side sound hole and the first cover part side sound hole, and the second sealing member side sound hole and the second cover part side The difference between the sound pressure of the sound reaching one side of the vibrating part and the sound pressure of the sound reaching the other side of the vibrating part when the sound reaches the other side of the vibrating part through the sound hole The microphone unit according to claim 1, wherein the microphone unit is configured to detect pressure.   The microphone unit according to claim 1, wherein a protruding height of the convex portion of the sealing member is substantially equal to a depth of the concave portion of the cover portion.   Either one of the inner side surface of the recessed part formed in the said cover part or the outer side surface of the convex part formed in the said sealing member is formed in the taper shape which tapers. The microphone unit according to item 1. The sealing member is made of an elastically deformable material,
The outer surface of the convex portion formed on the sealing member is formed in a tapered shape that tapers,
The inner surface of the recess formed in the cover part is formed in a substantially rectangular shape,
The microphone unit according to claim 6, wherein a width of an opening end of the concave portion of the cover portion is smaller than a width of a root portion of the convex portion of the sealing member.   At least any one of the inner side surface of the recessed part formed in the said cover part or the outer side surface of the convex part formed in the said sealing member is formed in uneven | corrugated shape. The microphone unit according to item.   The sealing member is made of an elastically deformable material, and the outer surface of the convex portion of the sealing member is elastically deformed so as to follow the shape of the inner surface of the concave portion of the cover portion. The microphone unit according to claim 1, wherein the microphone unit is engaged with an inner side surface of the concave portion.   The microphone according to any one of claims 1 to 9, wherein the sealing member is disposed so as to seal between a back side of a product housing in which the microphone is accommodated and the cover portion. unit. A conductive shield member disposed between the cover portion and the sealing member and having an opening for allowing the convex portion of the sealing member to escape;
The microphone unit according to claim 1, wherein a protruding height of the convex portion of the sealing member is greater than a thickness of the shield member. A substrate provided with a vibration part that vibrates by sound pressure, a cover part disposed on the substrate so as to cover the vibration part, and a sealing member disposed on a surface of the cover part, The sealing member includes a sealing member side sound hole and a convex portion that surrounds the periphery of the sealing member side sound hole and protrudes from the surface of the sealing member to the cover portion side, and the cover portion is the sealing member A cover part-side sound hole formed so as to be connected to the sealing member-side sound hole of the member, and a concave part disposed at a position corresponding to the convex part of the sealing member, at least of the concave part of the cover part A microphone unit in which the inner surface and the outer surface of the convex portion of the sealing member are in close contact, and the concave portion of the cover portion and the convex portion of the sealing member are fixedly engaged;
A portable device housing in which the microphone unit is housed,
The said sealing member is a portable apparatus arrange | positioned so that the back surface side of the said portable apparatus housing | casing and the said cover part may be sealed.

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