JP2014099789A - Microphone and mounting structure of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve microphone characteristics and mountability.SOLUTION: The microphone includes: a substrate part; a cover part of a hollow box shape at one of the surfaces of which an aperture for covering the substrate part is formed; and a microphone sound hole for sound collection formed on one of the surfaces among a plurality of surfaces contacting a surface at which the aperture of the cover part is formed.

Description

  The present invention relates to a microphone mounted on a mobile terminal or the like and a mounting structure thereof.

  In recent mobile terminals represented by smartphones, microphones that can be soldered by reflow (hereinafter referred to as “reflow type microphones”) are used. On the other hand, in order to improve the design, there are an increasing number of portable terminals in which the transmission sound hole (microphone sound hole) is arranged as inconspicuous as possible, for example, on the side surface of the housing.

  FIG. 15 is an external perspective view of a general mobile terminal 1 in which the transmission sound holes are arranged inconspicuously. A display unit 3 is arranged at the center of the surface of the mobile terminal 1. A reception sound hole 4 is formed on the surface of the upper end portion of the mobile terminal 1. A transmission sound hole 2 is formed on the side surface (bottom surface 5) of the lower end portion of the mobile terminal 1. The mobile terminal 1 includes a front housing 6 and a rear housing 7. In the following, it is assumed that the reception sound hole 4 is formed in the front housing 6 and the transmission sound hole 2 is formed in the rear housing 7.

  FIG. 16 is an external perspective view of a general reflow microphone 10. FIG. 17 is an internal configuration diagram of the reflow microphone 10. The reflow type microphone 10 includes a cover portion 11 and a substrate 14. At least the amplification unit 12 and the diaphragm unit 13 are mounted on one surface of the substrate 14. An electrode portion 16 is formed on the opposite surface of the substrate 14. A microphone sound hole 15 is formed on the upper surface of the cover portion 11 (the surface opposite to the surface on which the substrate 14 is attached).

  FIG. 18 is a perspective view of main parts of the mobile terminal 1. The mobile terminal 1 includes a substrate 20. The reflow type microphone 10 is mounted on the end portion of the substrate 20. The reflow type microphone 10 is held by a microphone holder 30.

  FIG. 19 is a cross-sectional view of a main part of the mobile terminal 1. The substrate 20 on which the reflow microphone 10 is mounted is positioned at a predetermined position of the front housing 6. A transmission sound hole 2 is formed on the bottom surface of the rear housing 7. In a state where the front housing 6 and the rear housing 7 are fitted, sound input from the transmission sound hole 2 is formed by the reflow microphone 10, the rear housing 7, and the microphone holder 30. The sound is guided to the microphone sound hole 15 disposed on the upper surface of the reflow microphone 10 through the sound path 32 which is a sealed space.

  Further, Patent Document 1 describes a mobile terminal in which a microphone having a microphone sound hole formed on the upper surface is mounted toward the bottom surface.

JP 2009-111696 A (Page No. 7-8 and FIG. 5)

  As described above, in the reflow microphone 10, the microphone sound hole 15 is formed on the upper surface of the cover portion 11. Therefore, when the reflow microphone 10 is incorporated in the portable terminal 1 in which the transmission sound hole 2 is formed on the bottom surface, as shown in FIG. 19, the arrangement of the microphone sound hole 15 and the transmission sound hole 2 is as follows. The arrangement is such that both hole axes are in an orthogonal state. In other words, the sound path 32 becomes complicated and long, which is bent several times.

  FIG. 20 is a graph showing changes in microphone characteristics due to differences in the length of the microphone sound path. As shown in FIG. 20, generally, when the sound path becomes longer, the sensitivity in the high sound range tends to be too high. The characteristic that the microphone sensitivity is as flat as possible in the entire sound range is the ideal microphone characteristic.

  However, in the case of the reflow type microphone 10, since the sound path 32 becomes long as described above, the sensitivity in the high sound range becomes too high, and it is difficult to obtain good microphone characteristics.

  Moreover, when trying to seal a complicated path as described above, there is a concern about the complexity of the sealing structure (complexity of the shape of the microphone holder 30). Specifically, as shown in FIGS. 18 and 19, it is necessary to prepare a microphone holder 30 that can hold the reflow microphone 10 from two directions (Z direction and Y direction).

  Further, generally, when a reflow type microphone is automatically mounted on a substrate, the upper surface portion is adsorbed by an adsorption nozzle. In this case, if the suction nozzle sucks the microphone sound hole 15, a microphone failure such as deformation of internal components (particularly the diaphragm portion 13) may occur due to suction force generated inside the microphone. Therefore, it is necessary to adsorb limitedly only the adsorption area S1 (see FIG. 16) avoiding the microphone sound hole 15. Moreover, in recent years, the reflow microphone 10 has been miniaturized, and the suction area S1 tends to become narrower. When the suction area S1 is narrowed, more and more consideration is necessary to prevent the microphone sound hole 15 from being sucked by mistake. That is, the reflow microphone 10 has a problem that workability at the time of automatic mounting is lowered.

  On the other hand, Patent Document 1 describes a structure in which a microphone is inclined by 90 degrees and a sound hole of the microphone is directed to the bottom surface. Such a structure increases the possibility of avoiding deterioration of the microphone characteristics and complication of the sound path sealing structure. However, in the case of the structure as disclosed in Patent Document 1, it is necessary to mount a microphone on a dedicated flexible substrate or the like, which may complicate the mounting structure. Further, there may be a case where such a mounting structure itself cannot be adopted due to restrictions on the size of the mobile terminal.

  The present invention has been made to solve the above problems, and an object thereof is to provide a microphone excellent in microphone characteristics and mountability and a mounting structure thereof.

  The microphone of the present invention has a substrate portion, a hollow box shape, a cover portion in which an opening for covering the substrate portion is formed on any one surface, and the opening of the cover portion. And a microphone hole for sound collection formed on any one of a plurality of surfaces in contact with the surface.

  According to the present invention, it is possible to improve microphone characteristics and mountability.

The disassembled perspective view of the microphone which concerns on the 1st Embodiment of this invention is shown. The principal part sectional drawing of the portable terminal incorporating the microphone shown in FIG. 1 is shown. The external appearance perspective view of the reflow type | mold microphone which concerns on the 2nd Embodiment of this invention is shown. The internal block diagram of the reflow type microphone which concerns on the 2nd Embodiment of this invention is shown. The principal part perspective view of the 1st mounting structure of the reflow type microphone which concerns on 2nd Embodiment is shown. Sectional drawing of the principal part of the 1st mounting structure of the reflow type microphone which concerns on 2nd Embodiment is shown. The principal part perspective view of the 2nd mounting structure of the reflow type microphone which concerns on 2nd Embodiment is shown. The principal part sectional drawing of the 2nd mounting structure of the reflow type microphone which concerns on 2nd Embodiment is shown. The principal part perspective view of the 3rd mounting structure of the reflow type microphone which concerns on 2nd Embodiment is shown. The principal part top view of the 3rd mounting structure of the reflow type microphone which concerns on 2nd Embodiment is shown. The principal part sectional view of the 3rd mounting structure of the reflow type microphone concerning a 2nd embodiment is shown. The principal part perspective view of the 4th mounting structure of the reflow type microphone which concerns on 2nd Embodiment is shown. The principal part top view of the 4th mounting structure of the reflow type microphone which concerns on 2nd Embodiment is shown. The principal part sectional view of the 4th mounting structure of the reflow type microphone concerning a 2nd embodiment is shown. An external perspective view of a general portable terminal is shown. An external perspective view of a general reflow type microphone is shown. The internal block diagram of a general reflow type microphone is shown. The principal part perspective view of the portable terminal shown in FIG. 15 is shown. FIG. 16 is a cross-sectional view of a main part of the mobile terminal shown in FIG. The graph which showed the change of the microphone characteristic by the difference in the length of a microphone sound path is shown.

[First Embodiment]
FIG. 1 is an exploded perspective view of a microphone 100 according to the first embodiment of the present invention. The microphone 100 includes a substrate unit 102 and a cover unit 104. The cover portion 104 has a hollow box shape, and an opening 108 for covering the substrate portion 102 is formed on any one surface. A microphone sound hole 106 for collecting sound is formed on the side surface of the cover portion 104 (any one of a plurality of surfaces in contact with the surface on which the opening 108 is formed).

  The microphone 100 is incorporated in a predetermined device, for example, the mobile terminal 200. FIG. 2 is a cross-sectional view of a main part of the mobile terminal 200 in which the microphone 100 is incorporated. The microphone 100 is mounted on the substrate 202. On the other hand, a transmission sound hole 206 is provided on the bottom surface of the housing 204 of the mobile terminal 200. The substrate 202 is arranged in the housing 204 so that the side on which the microphone 100 is mounted is directed to the transmission sound hole 206 side. In the housing 204, the path connecting the transmission sound hole 206 and the microphone sound hole 106 is sealed by a sealing member 250. The sealed space forms a sound path 252.

  As described above, the microphone sound hole 106 is formed on the side surface of the cover portion 104 in the microphone 100. When the microphone 100 is assembled in the portable terminal 200 having the transmission sound hole 206 formed on the bottom surface, the microphone sound hole 106 can be opposed to the transmission sound hole 206, so that the length of the sound path 252 is shortened. It becomes possible to make it. Accordingly, it is possible to obtain a flat microphone characteristic in the entire sound range while suppressing the sensitivity from rising only in the high sound range.

  Further, by making the microphone sound hole 106 face the transmission sound hole 206, as shown in FIG. 2, the holding direction (compression direction) of the sealing member 250 is set to only one direction (Y direction in FIG. 2). Is possible. Therefore, in the case of the microphone 100, the sealing structure of the sound path 252 (the structure of the sealing member 250 and the mounting workability) can be simplified as compared with the general reflow microphone 10 (see FIG. 16 or FIG. 19). .

  In addition, in the case of the microphone 100, since the microphone sound hole 106 is formed on the side surface of the cover portion 104, the entire upper surface (the surface opposite to the surface on which the opening portion 108 is formed) of the cover portion 104 is used as the suction area. it can. Therefore, when the microphone 100 is automatically mounted on the substrate 202, troublesome considerations such as avoiding the microphone sound hole 106 are unnecessary. Furthermore, even if erroneous suction occurs, the possibility that the diaphragm member (not shown) inside the microphone 100 is damaged is extremely low.

In summary, the microphone 100 according to the first embodiment can improve the microphone characteristics and mountability.
[Second Embodiment]
(1) Reflow Microphone FIG. 3 is an external perspective view of a reflow microphone 300 according to the second embodiment of the present invention. FIG. 4 is an internal configuration diagram of the reflow type microphone 300.

  The reflow type microphone 300 includes a substrate unit 302 and a cover unit 304.

  At least the diaphragm portion 310 and the amplifying portion 312 are mounted on one surface of the substrate portion 302. The diaphragm 310 converts an acoustic signal into an electrical signal. The amplifying unit 312 amplifies the electrical signal generated by the diaphragm unit 310 in order to facilitate signal processing in a subsequent circuit (not shown). An electrode part 314 is formed on the other surface of the substrate part 302. The electrode unit 314 is soldered to a pad on a device-side (for example, portable terminal) substrate.

  The cover unit 304 covers the substrate unit 302 from above. Specifically, the cover 304 has a hollow box shape, and an opening 308 (see FIG. 4) for covering the substrate 302 is formed on any one surface. In order to prevent unnecessary sound from entering the reflow microphone 300, the contact portion between the substrate portion 302 and the cover portion 304 is sealed with an adhesive or a sealing material. A microphone hole 306 for collecting sound is formed on the side surface of the cover portion 304 (any one of a plurality of surfaces in contact with the surface where the opening 308 is formed).

  When the reflow type microphone 300 described above is incorporated into a portable terminal in which the transmission sound hole is formed on the bottom surface, the microphone sound hole 306 can be opposed to the transmission sound hole. As a result, the sound path can be shortened. By shortening the sound path, it is possible to obtain a flat microphone characteristic in the whole sound range by suppressing the sensitivity from being raised only in the high sound range.

  Furthermore, by making the microphone sound hole 306 face the transmission sound hole on the apparatus side, the microphone holder can be held in only one direction (compression direction). Therefore, in the case of the reflow type microphone 300, the sound path sealing structure can be simplified as compared with the general reflow type microphone 10 (see FIG. 16 or FIG. 19).

  Moreover, in the case of the reflow type microphone 300, since the microphone sound hole 306 is formed on the side surface of the cover portion 304, the entire upper surface of the cover portion 304 (the surface opposite to the surface on which the opening 308 is formed) is covered with the suction area S2 ( FIG. 3). Therefore, when the reflow type microphone 300 is automatically mounted on the board on the apparatus side, troublesome considerations such as avoiding the microphone sound hole 306 are unnecessary. Further, even if erroneous suction occurs, the possibility that the microphone sound hole 306 is directly sucked is extremely low, so the concern that the diaphragm 310 is damaged is eliminated.

  In summary, the reflow microphone 300 of the second embodiment can improve microphone characteristics and mountability.

  It is sufficient that the microphone sound hole 306 is formed in any one of a plurality of side surfaces (for example, four when the reflow type microphone 300 is a rectangular parallelepiped or a cube). More preferably, it is formed on the side surface where the distance between the diaphragm portion 310 and the diaphragm portion 310 is shortened. Thereby, the sound path can be further shortened, and the microphone sensitivity can be improved.

  Further, when there is a margin in the mounting size in the height direction (Z direction shown in FIG. 4), it is preferable to increase the height of the reflow microphone 300 (substantially the height of the cover 304) as much as possible. . As a result, the sound path space in the reflow microphone 300 is increased, and the sound can be efficiently transmitted to the diaphragm during sound collection. Therefore, the microphone sensitivity can be further improved. Furthermore, when the height dimension of the cover part 304 increases, the contact area with the microphone holder increases. Therefore, more reliable sealing is possible.

Examples of the material of the cover part 304 include a metal or a substrate material such as FR4. FR4 is an abbreviation of Flame Regentant Type 4, and is also called a glass cloth base epoxy resin multilayer substrate material (glass epoxy multi) or the like.
(2) Mounting Structure of Reflow Microphone Hereinafter, mounting structures (2-1) to (2-4) when the above-described reflow microphone 300 is mounted on the mobile terminal 1 shown in FIG. 15 will be described. In all the mounting structures (2-1) to (2-4), the reflow microphone 300 described in (1) is used. Even when the reflow microphone 300 is mounted, the configuration of the mobile terminal 1 is basically the same as the components shown in FIGS. 15, 18, and 19. However, some components may have different shapes depending on the mounting structure. In this case, the components are distinguished by adding alphabets A, B,.
(2-1) First Mounting Structure FIG. 5 is a perspective view of a main part of the first mounting structure. FIG. 6 is a cross-sectional view of a main part of the first mounting structure. The portable terminal 1A includes a substrate 20A. The reflow type microphone 300 is mounted on the end of the substrate 20A. Specifically, for example, the end portion of the reflow microphone 300 and the end portion of the substrate 20A are substantially flush with each other, or the end portion of the reflow microphone 300 is inside the end portion of the substrate 20A, that is, the substrate is closer to the end portion. It is mounted so as to be closer to the center of 20A. The board 20A on which the reflow microphone 300 is mounted is positioned at a predetermined position of the front housing 6 of the mobile terminal 1A.

  For design reasons, the transmission sound hole 2 is formed on the bottom surface of the mobile terminal 1 </ b> A (specifically, the side surface of the lower end of the rear housing 7). As described above, the microphone sound hole 306 of the reflow microphone 300 is formed on the side surface of the cover portion 304. Therefore, when the front housing 7 and the rear housing 6 are fitted, the microphone sound hole 306 of the reflow microphone 300 faces the transmission sound hole 2 formed in the rear housing 6.

  A microphone holder 30 </ b> A (sealing member) is interposed between the transmission sound hole 2 and the microphone sound hole 306. The microphone holder 30A is formed of a hermetically sealed material. The microphone holder 30A has at least a plate-like portion, and a through-hole 400 having a size that does not shield the microphone sound hole 306 and the transmission sound hole 2 is formed at a substantially central portion of the plate-like portion. In this mounting structure, a case where the microphone holder 30A is formed in a substantially square shape will be described as an example.

  The microphone holder 30 </ b> A is affixed in advance to the inner wall portion around the transmission sound hole 2 of the rear housing 7 with, for example, a double-sided tape. When the rear housing 7 and the front housing 6 are fitted together, the microphone holder 30A is compressed, and finally the sound path 32A is formed. In this case, the compression direction of the microphone holder 30A is only the direction in which the reflow microphone 300 and the rear housing 7 face each other (the Y direction in FIG. 6).

  In the first mounting structure described above, when the reflow type microphone 300 is mounted on the portable terminal 1A in which the transmission sound hole 2 is formed on the bottom surface, the microphone sound hole 306 faces the transmission sound hole 2. To be arranged. Accordingly, the length of the sound path 32A is shortened, and a flat microphone characteristic can be obtained in the entire sound range by suppressing the sensitivity from protruding only in the high sound range.

  Furthermore, in the first mounting structure described above, since the microphone holder 30A can be held in only one direction (compression direction), the sealing structure of the sound path 32A can be simplified. .

In addition, when the area of the side surface of the reflow type microphone 300 is small, the size of the microphone holder 30A itself is also small, and there is a possibility that the assembly workability is lowered. In such a case, the microphone holder 30A can be sized to include not only the side surface of the reflow microphone 300 but also the substrate 20A portion as a sealed region. By doing in this way, workability | operativity can be maintained, ensuring airtightness.
(2-2) Second Mounting Structure FIG. 7 is a perspective view of main parts of the second mounting structure. FIG. 8 is a fragmentary cross-sectional view of the second mounting structure. The portable terminal 1B includes a substrate 20B. The reflow type microphone 300 is mounted on the substrate 20B so that a part of the end on the side where the microphone sound hole 306 is formed protrudes from the substrate 20B. The board 20B on which the reflow microphone 300 is mounted is positioned at a predetermined position of the front housing 6 of the mobile terminal 1B. When the front housing 7 and the rear housing 6 are fitted together, the microphone sound hole 306 of the reflow microphone 300 is transmitted sound generated in the rear housing 6 as in the first mounting structure. Opposite the hole 2.

  A microphone holder 30 </ b> B (sealing member) is interposed between the transmission sound hole 2 and the microphone sound hole 306. The material and basic functions of the microphone holder 30B are the same as those of the microphone holder 30A in the first mounting structure. The difference between the two is the shape. The microphone holder 30 </ b> B is formed in a hollow box shape having a hole 402 that opens in only one direction in order to insert a part of the protruding end of the reflow microphone 300. A through hole 400 similar to the microphone holder 30 </ b> A is formed at a predetermined position on the bottom of the hole 402. The inner wall of the hole 402 is formed in a shape that matches the outer wall shape of the protruding portion of the reflow microphone 300.

  When the rear housing 7 and the front housing 6 are fitted, the protruding portion is inserted into the hole 402 of the microphone holder 30B. Thereafter, the microphone holder 30B is compressed, and finally, the sound path 32B which is a sealed space is formed. Note that the compression direction of the microphone holder 30B in this case is only the direction in which the reflow microphone 300 and the rear housing 7 face each other (the Y direction in FIG. 8), as in the case of the first mounting structure.

  By the second mounting structure described above, the flattening of the microphone characteristics and the simplification of the sealing structure are achieved as in the first mounting structure.

  Furthermore, according to the second mounting structure, the reflow microphone 300 (that is, the microphone sound hole 306) and the transmission sound hole 2 can be brought closer to each other. As a result, the microphone characteristics can be further improved.

  Further, when the microphone holder 20B is fixed, it is only necessary to attach the microphone holder 20B to the protruding tip portion of the reflow type microphone 300, and operations such as gluing and positioning are unnecessary. Therefore, it is possible to improve the workability of assembly (or replacement).

The size of the hole 402 of the microphone holder 20B is preferably set slightly smaller than the size of the protruding tip of the reflow microphone 300. Thereby, since the reflow type microphone 300 and the microphone holder 30B are press-fitted and attached, they are more firmly adhered to each other, the sealing performance is improved and the drop-off prevention is also achieved.
(2-3) Third Mounting Structure FIG. 9 is a perspective view of main parts of the third mounting structure. FIG. 10 is a top view of an essential part of the third mounting structure. FIG. 11 is a cross-sectional view of a main part of the third mounting structure.

  The portable terminal 1C includes a substrate 20C. On both sides of the area of the substrate 20C where the reflow microphone 300 is mounted, a notch 350 is formed by notching a predetermined length from the end of the substrate 20C.

  The reflow type microphone 300 is mounted on the substrate 20C so that the end portion on the side where the microphone sound hole 306 is formed and the end portion of the substrate 20C are substantially flush with each other. That is, in the case of the third mounting structure, the entire area of the bottom surface of the reflow microphone 300 (the surface on the side where the back surface of the substrate portion 302 is exposed) is fixed to the substrate 20C.

  A microphone holder 30 </ b> C (sealing member) is interposed between the transmission sound hole 2 and the microphone sound hole 306. The material and basic functions of the microphone holder 30C are the same as those of the microphone holder 30B in the second mounting structure. The difference between the two is the shape. The inner wall shape of the hole 402 of the microphone holder 30C is the same as the inner wall shape of the microphone holder 30B, but the outer wall shape of the microphone holder 30C is formed in a shape that matches the inner wall shape of the substrate 20C in the notch 350. .

  When fitting the rear housing 7 and the front housing 6, the side wall of the microphone holder 30 </ b> C (the wall rising from the bottom of the hole 402) is inserted into the notch 350. In this case, the tip end portion of the substrate 20C corresponding to the length in the depth direction of the notch 350 is inserted into the hole 402 of the microphone holder 30C. Thereafter, the microphone holder 30C is compressed, and finally the sound path 32C, which is a sealed space, is formed. In this case, the compression direction of the microphone holder 30B is only the direction in which the reflow microphone 300 and the rear housing 7 face each other (the Y direction in FIG. 11), as in the case of the first mounting structure.

  By the third mounting structure described above, the flattening of the microphone characteristics and the simplification of the sealing structure are achieved as in the first mounting structure.

  Furthermore, according to the third mounting structure, similarly to the second mounting structure, it is possible to further improve the microphone characteristics and improve the workability of assembly (or replacement).

  Furthermore, in the case of the third mounting structure, the entire bottom area of the reflow microphone 300 is fixed to the substrate 20C. Therefore, it is possible to reduce the risk that the reflow microphone 300 will fall off the substrate 20C. Of course, even in this case, the state where the microphone sound hole 306 and the transmission sound hole 2 are close to each other is maintained.

  Note that the size (width, depth) of the notch 350 is preferably as small as possible. The reason is that it is possible to suppress as much as possible a decrease in strength at the edge of the substrate due to the provision of the notch 350.

In addition, it is preferable that the size of the hole 402 of the microphone holder 20C is set slightly smaller than the size of the protruding tip of the reflow type microphone 300. Furthermore, it is preferable that the thickness of the side wall of the microphone holder 30 </ b> C is set slightly larger than the width of the notch 350. Thereby, since the reflow type microphone 300 and the microphone holder 30C are press-fitted and attached, they are more firmly adhered to each other, the sealing performance is improved and the drop-off prevention is also achieved.
(2-4) Fourth Mounting Structure Example FIG. 12 is a main part perspective view of the fourth mounting structure. FIG. 13 is a top view of an essential part of the fourth mounting structure. FIG. 14 is a cross-sectional view of a main part of the fourth mounting structure.

  The portable terminal 1D includes a substrate 20D. On both sides of the area where the reflow microphone 300 of the substrate 20D is mounted, a notch 350 is formed by notching a predetermined length from the end of the substrate 20D, as in the case of the third mounting structure. The In the case of the substrate 20D, a concave portion 352 corresponding to the shape of the convex portion 354 of the microphone holder 30D, which will be described later, is further formed at a predetermined position in the deepest portion of the notch portion 350.

  The reflow microphone 300 is mounted on the substrate 20D so that the end on the side where the microphone sound hole 306 is formed and the end of the substrate 20D are substantially on the same plane. That is, as in the case of the third mounting structure, the entire area of the bottom surface of the reflow microphone 300 is fixed to the substrate 20D.

  A microphone holder 30 </ b> D (sealing member) is interposed between the transmission sound hole 2 and the microphone sound hole 306. The material and basic functions of the microphone holder 30D are the same as those of the microphone holder 30C in the third mounting structure. The difference between the two is the shape. At predetermined positions on the outer surfaces of the pair of side walls (the walls rising from the bottom of the hole 402) in the lateral direction of the microphone holder 30D (the X direction shown in FIGS. 12 and 13), a protrusion 354 for preventing removal is provided. It is formed.

  When fitting the rear housing 7 and the front housing 6, the side wall of the microphone holder 30 </ b> D is inserted into the notch 350. Furthermore, the tip portion of the substrate 20D corresponding to the length of the notch 350 in the depth direction is inserted into the hole 402 of the microphone holder 30D. When the tip of the microphone holder 30D reaches the deepest portion of the notch 350, the convex portion 354 formed at the tip of the microphone holder 30D is fitted into the recess 352 of the notch 350. Thereafter, the microphone holder 30D is compressed, and finally the sound path 32D which is a sealed space is formed. Note that the compression direction of the microphone holder 30D in this case is only the direction in which the reflow microphone 300 and the rear housing 7 face each other (the Y direction shown in FIG. 14), as in the case of the first mounting structure. .

  According to the 4th mounting structure demonstrated above, the effect similar to a 3rd mounting structure can be acquired.

  Further, in the case of the fourth mounting structure, since it has the above-described prevention function, the depth dimension of the notch 350 can be shortened. Thereby, the notch area | region of board | substrate 20D can further be reduced, and it becomes possible to suppress further the intensity | strength fall of the board | substrate edge part by having provided the notch part 350. FIG.

  In FIG. 12, a case where the convex portion 354 is partially formed in the height direction (Z direction shown in FIG. 12) of the outer surface of the side wall of the microphone holder 30D is taken as an example. However, the convex portion 354 may be formed over the entire region in the height direction. Moreover, the convex part 354 may be plural.

  The material of the microphone holders 30A to 30D may be any material as long as it can be sealed and compressed. Examples of the material of the microphone holders 30 </ b> A to 30 </ b> D include a material having an independent foam structure such as a poron material, and silicon rubber having a low hardness that can absorb unevenness.

  In addition, in 2nd Embodiment, the case where the reflow type | mold microphone which comprises a rectangular parallelepiped (all surfaces are rectangles) and the microphone sound hole was provided in the side surface of a short side was mentioned as an example. However, the first to fourth mounting structures can also be applied to mounting of a reflow type microphone in which a microphone sound hole is provided on the side surface on the long side. The first to fourth mounting structures can also be applied to mounting a reflow microphone that forms a quadrangular prism (including a non-rectangular surface) or a cube (all surfaces are square).

  Further, the first to fourth mounting structures are not limited to the portable terminal in which the microphone sound hole is formed on the bottom surface, and can be applied to a portable terminal in which the microphone sound hole is formed on the side surface or the top surface. is there.

  Specific examples of the mobile terminal include a mobile phone, a tablet terminal, a notebook computer, and a digital camera.

DESCRIPTION OF SYMBOLS 1, 1A, 1B, 1C, 1D Portable terminal 2 Transmission sound hole 3 Display part 4 Reception sound hole 5 Bottom surface 6 Front side housing | casing 7 Rear side housing | casing 10 Reflow type microphone 11 Cover part 12 Amplifying part 13 Diaphragm part 14 Substrate 15 Microphone sound hole 16 Electrode portion 20, 20A, 20B, 20C, 20D Substrate 30, 30A, 30B, 30C, 30D Microphone holder 32, 32A, 32B, 32C, 32D Sound path 100 Microphone 102 Substrate portion 104 Cover portion 106 Microphone sound hole 108 Opening portion 200 Mobile terminal 202 Substrate 204 Case 206 Transmission sound hole 250 Sealing member 252 Sound path 300 Reflow type microphone 302 Substrate portion 304 Cover portion 306 Microphone sound hole 308 Opening portion 310 Vibration plate portion 312 Amplifying portion 314 Electrode part 350 Notch part 352 Concave part 354 Convex part 400 Through-hole 402 Hole part S1 Suction area S2 Suction area

Claims (9)

A substrate section;
A cover part in which an opening for forming the hollow box shape and covering the substrate part on any one surface is formed;
A microphone hole for sound collection formed on any one of a plurality of surfaces in contact with a surface on which the opening of the cover is formed;
A microphone comprising: A vibration plate portion that converts an acoustic signal input from the microphone sound hole into an electric signal is mounted on the substrate portion,
The microphone according to claim 1, wherein the microphone sound hole is formed on any one of the surfaces where the distance from the diaphragm portion is shortened.   The microphone according to claim 1 or 2, wherein the microphone is a reflow type microphone that can be soldered by reflow. The microphone according to any one of claims 1 to 3,
A substrate on which the microphone is mounted;
A housing in which the substrate is incorporated and a transmission sound hole is formed at a predetermined position;
There is a through-hole that is interposed between the microphone and the inner wall of the housing, and is not shielded by the microphone sound hole and the transmission sound hole. A sealing member that seals a path connecting the microphone sound hole and the transmission sound hole by being compressed to
With
In the housing, the substrate is disposed so that the microphone sound hole and the transmission sound hole face each other.
The microphone mounting structure, wherein the compression direction of the sealing member is only the direction in which the microphone sound hole and the transmission sound hole face each other. The microphone is mounted on the substrate such that an end portion of the microphone on which the microphone sound hole is formed protrudes from an end portion of the substrate.
The sealing member is formed in a hollow box shape having a hole opened in only one direction for inserting the protruding end of the microphone, and the through hole is formed at a predetermined position on the bottom of the hole, The inner wall of the hole is formed in a shape that matches the outer wall shape of the protruding end of the microphone,
The microphone mounting structure according to claim 4, wherein the sealing member is attached to the microphone.   The microphone mounting structure according to claim 5, wherein the size of the hole is set smaller than the size of the microphone. On both sides of the area where the microphone is mounted on the substrate, a notch is formed by cutting out a predetermined length from the end of the substrate,
The microphone is mounted on the substrate so that an end portion of the microphone where the microphone sound hole is formed and an end portion of the substrate are substantially on the same plane,
The sealing member is formed in a hollow box shape having a hole portion opened in only one direction for inserting the end portion of the microphone in the notch portion, and the through hole is formed at a predetermined position of the bottom portion of the hole portion. The inner wall of the hole is formed in a shape matching the shape of the outer wall of the microphone in the notch, and the outer wall of the side wall rising from the bottom is shaped to match the shape of the inner wall of the substrate in the notch. Formed,
The microphone mounting structure according to claim 4, wherein the sealing member is attached to the microphone and the substrate. The size of the hole is set smaller than the size of the microphone,
The microphone mounting structure according to claim 7, wherein a thickness of the side wall is set larger than a width of the notch portion of the substrate. At a predetermined position of the outer wall of the side wall, a protruding portion for preventing removal is formed,
A recess is formed at a predetermined position of the notch according to the shape of the protrusion,
The microphone mounting structure according to claim 7 or 8, wherein when the sealing member is attached to the microphone and the substrate, the convex portion is fitted into the concave portion.

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