JP4116169B2

JP4116169B2 - Electromagnetic sound generator

Info

Publication number: JP4116169B2
Application number: JP32652398A
Authority: JP
Inventors: 睦桑原
Original assignee: Citizen Electronics Co Ltd
Current assignee: Citizen Electronics Co Ltd
Priority date: 1998-11-17
Filing date: 1998-11-17
Publication date: 2008-07-09
Anticipated expiration: 2018-11-17
Also published as: JP2000151778A

Description

【０００１】
【発明の属する技術分野】
本発明は、携帯電話やポケットベル等の移動通信機器に組み込まれて、受信の際に着信音等を発する電磁型発音体であって、特に移動通信機器内のプリント基板等に表面実装される電磁型発音体に関する。
【０００２】
【従来の技術】
従来、この種の電磁型発音体としては、例えば図９に示したように、直方体の樹脂製ケーシング２内に振動発音部（図示せず）を内蔵した薄型タイプのブザー１が知られている。このブザー１は、図１０及び図１１に示したように、プリント基板４の上に表面実装された状態で携帯電話等のボディケース３内に組み込まれている。ケーシング２の前面には放音孔５が開設されており、この放音孔５がボディケース３に設けられた外部放音孔６と同軸上に設定されている。また、ブザー１の放音孔５から放出された着信音がボディケース３内にこもってしまうのを防止するため、放音孔５と前記ボディケース３の外部放音孔６との隙間には音漏れ防止用のパッキン７が配設される。このパッキン７には、図示したように、ブザー１のケーシング２全体が嵌まり込む凹所７ａと、放音孔５と外部放音孔６とを連通させる貫通孔７ｂとが形成されており、ブザー１をプリント基板４上に実装したのちにケーシング２の上から被せられる。そして、前記ブザー１によって押圧変形され、ボディケース３の内壁面８に密着した状態で固定されている。
【０００３】
【発明が解決しようとする課題】
しかしながら、上記従来の電磁型発音体にあっては、ブザー１とパッキン７とが別体で供給されるために、携帯電話等への組付け時にはプリント基板４に実装したブザー１のケーシング２に別工程でパッキン７を取り付けなければならない。また、パッキン７がケーシング２の全体を覆うカバーとして構成されているために、その分プリント基板４上に占めるブザー１の専有体積が大きくなり、他の部品を搭載する際に制約が出てきてしまう等の問題があった。
【０００４】
そこで、本発明は、携帯電話等への組付け工程での工数を減らすと共に、プリント基板上に占める表面実装型電磁型発音体の専有体積を出来るだけ小さくすることを目的とする。
【０００５】
【課題を解決するための手段】
すなわち、本発明の請求項１に係る電磁型発音体は、内部に発音部を有する薄型のケーシングと、このケーシングに開設された放音孔と、この放音孔の前面側に配置された音漏れ防止部材とを備えた電磁型発音体において、前記ケーシングには放音孔より前方へ突出する係合部を設ける一方、音漏れ防止部材には前記係合部に差し込み固定される被係合部を設け、前記係合部は放音孔の左右両側に設けられ、放音孔の左右端からそれぞれ前方に延びる第１の係合壁及びこの第１の係合壁の先端からそれぞれ外方に延びる第２の係合壁で断面略Ｌ形状に形成された係合突起と、この係合突起とケーシングの壁面との間に形成された係合溝とで構成され、被係合部は、前記係合突起が嵌まり込む被係合溝及び前記係合溝に嵌まり込む被係合突起を有していることを特徴とする。
【０００６】
また、本発明の請求項２に係る電磁型発音体は、前記第１の係合壁は、音漏れ防止部材を差し込んだときに音漏れ防止部材の左右方向を位置決めし、第２の係合壁は音漏れ防止部材を差し込んだときに音漏れ防止部材の前後方向を位置決めすることを特徴とする。
【０００８】
【発明の実施の形態】
以下、添付図面に基づいて本発明に係る電磁型発音体の実施の形態を詳細に説明する。この実施例に係る電磁型発音体は、図１乃至図６に示すように、平面形状が略長方形の薄型ケーシング１２の内部に振動発音部（図示せず）を収納した携帯電話用の小型のブザー１１である。ケーシング１２は、ボックス状の樹脂製上ケース１２ａと、平板状の樹脂製下ケース１２ｂとで構成されており、振動発音部を搭載した下ケース１２ｂの上に上ケース１２ａを被せ、両者の突き合わせ部分を超音波溶着することによって一体に固着される。
【０００９】
前記上ケース１２ａは４つの側壁で囲まれた周面を有するが、その一つであるケーシング１２の前面１４には、図２に示したように、略中央部に横長矩形状の放音孔１５が開設されている。この放音孔１５は、振動発音部で発した着信音を外部に放出するためのもので、上ケース１２ａと下ケース１２ｂとを超音波溶着で一体に固着することによって形成される。また、この実施例では上ケース１２ａ側に放音孔１５を形づくる開口が形成されると共に、開口の左右側縁には前方に突出する係合部１６がそれぞれ形成されている。
【００１０】
上記係合部１６は、放音孔１５の左右開口端から放音孔１５の高さ幅で前方に突出する係合突起１７と、この係合突起１７とケーシング１２の前面１４との間に形成された係合溝１８とで構成される。前記係合突起１７は、ケーシング１２の前面１４から一体に延びる第１の係合壁１７ａと、この第１の係合壁１７ａの先端から外向きに約９０℃屈曲する第２の係合壁１７ｂとで略Ｌ字形に形成されている。なお、上記上ケース１２ａは、前後方向の寸法が下ケース１２ｂよりも短く、前記係合突起１７の第２の係合壁１７ｂが下ケース１２ｂの前端面１９と同一面上に位置している。また、下ケース１２ｂの四隅には、ブザー１１をプリント基板３０に表面実装するための外部接続電極２０が設けられている。
【００１１】
一方、前記放音孔１５の前面側には音漏れ防止部材としてのパッキン２１が配置される。このパッキン２１は全体が略直方体形状をしており、その中央部には前記放音孔１５と略同一形状の開口部２２が前後方向に貫通している。また、パッキン２１の裏面側には、上記上ケース１２ａの係合部１６に差し込み固定される被係合部２３が形成されている。この被係合部２３は上記ケーシング１２側の係合部１６に対応してパッキン２１の左右両側に設けられており、前記係合突起１７が嵌まり込む被係合溝２４と、係合溝１８に嵌まり込む被係合突起２５とで形成されている。また、パッキン２１の前面側には前記被係合突起２５より下方に延びる延長部２６がパッキン２１の幅方向全体に亘って形成されており、パッキン装着時にはこの延長部２６でケーシング１２の下ケース１２ｂの前端面１９を被覆する。
【００１２】
なお、上述したように、ケーシングの係合部１６にパッキン２１の被係合部２３を差し込むだけでパッキン２１を放音孔１５の前面に装着できるが、係合部１６または被係合部２３に予め接着剤等を塗布することで両者の結合がより大きなものとなる。また、上記パッキン２１は、柔軟性を備えたシリコンゴム等で形成される場合が多いが、シリコーンゴム以外にフッ素ゴムやアクリルゴム等の耐熱性に優れたゴム材料や樹脂材料、あるいは耐熱性必要としない場合にはウレタンゴムを利用することもできる。
【００１３】
次に、上記構成からなるブザー１１を携帯電話等のボディケース３１内に組み込む際の手順を説明する。先ず、振動発音部（図示せず）が搭載された下ケース１２ｂの上に上ケース１２ａを被せ、両者の突き合わせ部分を超音波溶着することによって一体化する。このようにして形成されたケーシング１２の前面１４にパッキン２１を上方から差し込み、上ケース１２ａの係合部１６にパッキン２１の被係合部２３を嵌め入れてパッキン２１を位置決め固定する。この時、パッキン２１の延長部２６で下ケース１２ｂの前端面１９を被覆する。このようにしてパッキン２１が装着されたブザー１１をプリント基板３０上に載置し、ケーシング１２の底部四隅に設けられた外部接続電極２０をプリント基板３０上のパターン電極（図示せず）にリフロー半田して、ブザー１１をプリント基板３０上に表面実装する。さらに、前記ブザー１１以外にも種々の電子部品等をプリント基板３０上に実装したのち、図６に示したように、このプリント基板３０を携帯電話等のボディケース３１内に組み込む。この時、パッキン２１の開口部２２をボディケース３１の外部放音孔３２と同じ軸上に位置合わせする。そして、ケーシング１２をボディケース３１の内壁面３３に向かって押圧することで、ケーシング１２の前面１４に装着されたパッキン２１を圧縮し、内壁面３３に密着させた状態でプリント基板３０を固定する。その結果、パッキン２１の開口部２２を介してブザー１１の放音孔１５とボディケース３１の外部放音孔３２とが連通し、またパッキン２１がケーシング１２の係合部１６にしっかりと嵌合された状態で押圧されることから、パッキン２１によって放音孔１５が閉塞してしまったり、パッキン２１の開口部２２が潰れてしまうといったこともなく、パッキン２１の装着部分から音が漏れてボディケース３１内に音がこもってしまうといったことがない。
【００１４】
図７及び図８は、本発明の第２実施例を示したものである。この実施例はケーシング１２に開設された放音孔１５の前方のみをパッキン２１で被覆し、パッキン２１の両側にケーシング１２の前面１４を露出させたものであり、図８に示したように、パッキン２１の裏面側において被係合部２３が角柱状の被係合突起２５と左右方向に連通する被係合溝２４とで構成されている以外は、前記実施例と同様の構成からなるので詳細な説明は省略する。
【００１５】
なお、ケーシング１２の係合部１６やパッキン２１の被係合部２３の形状を適宜設計変更することは可能であり、それに伴ってケーシング１２の下方側からパッキン２１を差し込んで係合部１６に位置決め固定することも可能である。
【００１６】
【発明の効果】
以上説明したように、本発明に係る電磁型発音体によれば、ケーシングには放音孔より前方へ突出する係合部を設ける一方、音漏れ防止部材には前記係合部に対しケーシングの上方側又は下方側から差し込み固定される被係合部を設けたので、ケーシングへの音漏れ防止部材の装着が容易となり、予め音漏れ防止部材を電磁型発音体のケーシングに装着しておくことで、携帯電話等への組み付け工数を減らすことができる。また、音漏れ防止部材をケーシングに開設された放音孔の前面側のみに配置したので、音漏れ防止部材自体を小型化することができ、プリント基板上に占める電磁型発音体の専有体積を小さくすることができる。
【００１７】
また、本発明によれば、前記係合部は音漏れ防止部材を位置決め固定する係合突起及び係合溝を有する一方、被係合部は前記係合突起が嵌まり込む被係合溝及び前記係合溝に嵌まり込む被係合突起を有しているので、係合部に被係合部を嵌め込むだけで、音漏れ防止部材を容易に且つ確実に装着できるといった効果がある。
【図面の簡単な説明】
【図１】本発明に係る電磁型発音体のパッキン装着後の斜視図である。
【図２】本発明に係る電磁型発音体の分解斜視図である。
【図３】本発明に係るパッキンを裏側から見た斜視図である。
【図４】上記図２におけるＢ−Ｂ線に沿った断面図である。
【図５】上記図２におけるＣ−Ｃ線に沿った断面図である。
【図６】上記電磁型発音体を携帯電話等のボディケースに組み込んだときの上記図１のＡ−Ａ線に沿った断面図である。
【図７】本発明に係る電磁型発音体の他の実施例を示す斜視図である。
【図８】上記図７におけるパッキンを裏側から見た斜視図である。
【図９】従来の電磁型発音体とパッキンとの組み合わせを示す斜視図である。
【図１０】従来の電磁型発音体を携帯電話等のボディケースに組み込んだときの概念図である。
【図１１】上記図１０のＤ−Ｄ線断面図である。
【符号の説明】
１１ブザー（電磁型発音体）
１２ケーシング
１５放音孔
１６係合部
１７係合突起
１７ａ第１の係合壁
１７ｂ第２の係合壁
１８係合溝
２１パッキン（音漏れ防止部材）
２３被係合部
２４被係合溝
２５被係合突起[0001]
BACKGROUND OF THE INVENTION
The present invention is an electromagnetic sounding body that is incorporated in a mobile communication device such as a mobile phone or a pager and emits a ring tone or the like upon reception, and is particularly surface-mounted on a printed circuit board or the like in the mobile communication device. It relates to an electromagnetic sounding body.
[0002]
[Prior art]
Conventionally, as this type of electromagnetic sounding body, for example, as shown in FIG. 9, a thin-type buzzer 1 in which a vibration sounding portion (not shown) is built in a rectangular resin casing 2 is known. . As shown in FIGS. 10 and 11, the buzzer 1 is incorporated in a body case 3 such as a mobile phone while being surface-mounted on a printed circuit board 4. A sound emitting hole 5 is formed in the front surface of the casing 2, and the sound emitting hole 5 is set coaxially with the external sound emitting hole 6 provided in the body case 3. In addition, in order to prevent the incoming sound emitted from the sound emitting hole 5 of the buzzer 1 from being trapped in the body case 3, the clearance between the sound emitting hole 5 and the external sound emitting hole 6 of the body case 3 is not provided. A packing 7 for preventing sound leakage is provided. As shown in the figure, the packing 7 is formed with a recess 7a into which the entire casing 2 of the buzzer 1 is fitted, and a through hole 7b that allows the sound emitting hole 5 and the external sound emitting hole 6 to communicate with each other. After mounting the buzzer 1 on the printed circuit board 4, the buzzer 1 is put on the casing 2. Then, it is pressed and deformed by the buzzer 1 and fixed in close contact with the inner wall surface 8 of the body case 3.
[0003]
[Problems to be solved by the invention]
However, in the conventional electromagnetic sounding body, since the buzzer 1 and the packing 7 are supplied separately, the casing 2 of the buzzer 1 mounted on the printed circuit board 4 is attached to the cellular phone or the like. The packing 7 must be attached in a separate process. In addition, since the packing 7 is configured as a cover that covers the entire casing 2, the exclusive volume of the buzzer 1 that occupies the printed circuit board 4 correspondingly increases, and restrictions are imposed when other components are mounted. There was a problem such as.
[0004]
Accordingly, an object of the present invention is to reduce the number of steps in the assembly process to a mobile phone or the like, and to reduce the exclusive volume of the surface mount electromagnetic sound generator on the printed circuit board as much as possible.
[0005]
[Means for Solving the Problems]
That is, the electromagnetic sounding body according to claim 1 of the present invention includes a thin casing having a sounding portion therein, a sound emitting hole opened in the casing, and a sound disposed on the front side of the sound emitting hole. in electromagnetic sounding body and a leakage prevention member to be, while providing an engagement portion which projects forwardly from the sound emission hole in the casing, the sound leakage prevention member is fixed lump to a difference in the engagement portion An engaging portion is provided , and the engaging portions are provided on both left and right sides of the sound emitting hole, respectively, and a first engaging wall extending forward from the left and right ends of the sound emitting hole and a tip of the first engaging wall, respectively. The engagement protrusion is formed by a second engagement wall extending outward and having a substantially L-shaped cross section, and an engagement groove formed between the engagement protrusion and the wall surface of the casing. The portion includes an engaged groove into which the engaging protrusion fits and an engaged protrusion to fit into the engaging groove. And characterized in that it.
[0006]
In the electromagnetic sounding body according to claim 2 of the present invention, the first engagement wall positions the sound leakage prevention member in the left-right direction when the sound leakage prevention member is inserted, and the second engagement wall The wall is characterized in that the sound leakage prevention member is positioned in the front-rear direction when the sound leakage prevention member is inserted .
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of an electromagnetic sounding body according to the present invention will be described below in detail with reference to the accompanying drawings. As shown in FIGS. 1 to 6, the electromagnetic sounding body according to this embodiment is a small-sized mobile phone in which a vibration sounding portion (not shown) is housed in a thin casing 12 having a substantially rectangular planar shape. It is a buzzer 11. The casing 12 is composed of a box-shaped resin upper case 12a and a plate-shaped resin lower case 12b. The upper case 12a is put on the lower case 12b on which the vibration sounding portion is mounted, and the two are matched. The parts are fixed together by ultrasonic welding.
[0009]
The upper case 12a has a peripheral surface surrounded by four side walls, and the front surface 14 of the casing 12, which is one of the upper case 12a, has a sound emitting hole having a horizontally long rectangular shape at a substantially central portion as shown in FIG. 15 has been established. The sound emitting hole 15 is for releasing a ringtone emitted from the vibration sounding portion to the outside, and is formed by integrally bonding the upper case 12a and the lower case 12b by ultrasonic welding. Further, in this embodiment, an opening for forming the sound emitting hole 15 is formed on the upper case 12a side, and engaging portions 16 projecting forward are formed on the left and right side edges of the opening.
[0010]
The engaging portion 16 includes an engaging protrusion 17 that protrudes forward from the left and right opening ends of the sound emitting hole 15 at the height of the sound emitting hole 15, and between the engaging protrusion 17 and the front surface 14 of the casing 12. It is comprised with the formed engaging groove 18. The engagement protrusion 17 includes a first engagement wall 17a that extends integrally from the front surface 14 of the casing 12, and a second engagement wall that bends outward by about 90 ° C. from the tip of the first engagement wall 17a. 17b and a substantially L-shape. The upper case 12a has a dimension in the front-rear direction shorter than that of the lower case 12b, and the second engagement wall 17b of the engagement protrusion 17 is located on the same plane as the front end face 19 of the lower case 12b. . In addition, external connection electrodes 20 for surface mounting the buzzer 11 on the printed circuit board 30 are provided at the four corners of the lower case 12b.
[0011]
On the other hand, a packing 21 as a sound leakage prevention member is disposed on the front side of the sound emitting hole 15. The entire packing 21 has a substantially rectangular parallelepiped shape, and an opening 22 having substantially the same shape as the sound emitting hole 15 penetrates in the front-rear direction at the center. Further, an engaged portion 23 that is inserted and fixed to the engaging portion 16 of the upper case 12 a is formed on the back surface side of the packing 21. The engaged portions 23 are provided on the left and right sides of the packing 21 corresponding to the engaging portions 16 on the casing 12 side, and the engaged grooves 24 into which the engaging protrusions 17 are fitted, and the engaging grooves 18 and an engaged protrusion 25 that fits into the member 18. Further, an extension portion 26 extending downward from the engaged protrusion 25 is formed on the front surface side of the packing 21 over the entire width direction of the packing 21, and when the packing is mounted, the extension portion 26 serves as a lower case of the casing 12. The front end face 19 of 12b is covered.
[0012]
As described above, the packing 21 can be attached to the front surface of the sound emitting hole 15 simply by inserting the engaged portion 23 of the packing 21 into the engaging portion 16 of the casing. By applying an adhesive or the like in advance, the bond between the two becomes greater. The packing 21 is often formed of flexible silicon rubber or the like. However, in addition to silicone rubber, a rubber material or resin material having excellent heat resistance such as fluoro rubber or acrylic rubber, or heat resistance is required. If not, urethane rubber can be used.
[0013]
Next, a procedure for incorporating the buzzer 11 having the above configuration into a body case 31 such as a mobile phone will be described. First, the upper case 12a is put on the lower case 12b on which a vibration sounding portion (not shown) is mounted, and the two butted portions are integrated by ultrasonic welding. The packing 21 is inserted into the front surface 14 of the casing 12 formed in this way from above, and the engaged portion 23 of the packing 21 is fitted into the engaging portion 16 of the upper case 12a to position and fix the packing 21. At this time, the front end surface 19 of the lower case 12 b is covered with the extension portion 26 of the packing 21. In this way, the buzzer 11 with the packing 21 attached is placed on the printed circuit board 30, and the external connection electrodes 20 provided at the bottom four corners of the casing 12 are reflowed to the pattern electrodes (not shown) on the printed circuit board 30. The buzzer 11 is surface-mounted on the printed circuit board 30 by soldering. Furthermore, after mounting various electronic components and the like other than the buzzer 11 on the printed circuit board 30, as shown in FIG. 6, the printed circuit board 30 is incorporated into a body case 31 such as a cellular phone. At this time, the opening 22 of the packing 21 is aligned on the same axis as the external sound emitting hole 32 of the body case 31. Then, by pressing the casing 12 toward the inner wall surface 33 of the body case 31, the packing 21 attached to the front surface 14 of the casing 12 is compressed, and the printed circuit board 30 is fixed in a state of being in close contact with the inner wall surface 33. . As a result, the sound emitting hole 15 of the buzzer 11 and the external sound emitting hole 32 of the body case 31 communicate with each other through the opening 22 of the packing 21, and the packing 21 is firmly fitted to the engaging portion 16 of the casing 12. Since the sound is released and the sound emitting hole 15 is not blocked by the packing 21 and the opening 22 of the packing 21 is not crushed, sound leaks from the mounting portion of the packing 21 and the body. There is no such a thing that the case 31 is filled with sound.
[0014]
7 and 8 show a second embodiment of the present invention. In this embodiment, only the front of the sound emission hole 15 opened in the casing 12 is covered with the packing 21 and the front surface 14 of the casing 12 is exposed on both sides of the packing 21, as shown in FIG. Since the engaged portion 23 is composed of a prismatic engaged protrusion 25 and an engaged groove 24 communicating in the left-right direction on the back side of the packing 21, it has the same configuration as in the above embodiment. Detailed description is omitted.
[0015]
The shape of the engaging portion 16 of the casing 12 and the engaged portion 23 of the packing 21 can be appropriately changed. Accordingly, the packing 21 is inserted from the lower side of the casing 12 to the engaging portion 16. It is also possible to fix the positioning.
[0016]
【The invention's effect】
As described above, according to the electromagnetic sounding body according to the present invention, the casing is provided with the engaging portion that protrudes forward from the sound emitting hole, while the sound leakage prevention member is provided with the casing against the engaging portion. Since the engaged part that is inserted and fixed from the upper side or the lower side is provided, it is easy to attach the sound leakage prevention member to the casing, and the sound leakage prevention member is previously attached to the casing of the electromagnetic sounding body. Thus, it is possible to reduce the number of man-hours for assembling the cellular phone. Moreover, since the sound leakage prevention member is disposed only on the front side of the sound emission hole provided in the casing, the sound leakage prevention member itself can be reduced in size, and the exclusive volume of the electromagnetic sounding body occupying on the printed circuit board can be reduced. Can be small.
[0017]
Further, according to the present invention, the engaging portion has an engaging protrusion and an engaging groove for positioning and fixing the sound leakage prevention member, while the engaged portion includes an engaged groove and a fitting groove into which the engaging protrusion is fitted. Since the engaged protrusions that fit into the engaging grooves are provided, there is an effect that the sound leakage prevention member can be easily and reliably attached only by fitting the engaged portion into the engaging portion.
[Brief description of the drawings]
FIG. 1 is a perspective view of an electromagnetic sounding body according to the present invention after packing is installed.
FIG. 2 is an exploded perspective view of an electromagnetic sounding body according to the present invention.
FIG. 3 is a perspective view of the packing according to the present invention as viewed from the back side.
4 is a cross-sectional view taken along line BB in FIG.
5 is a cross-sectional view taken along the line CC in FIG.
6 is a cross-sectional view taken along the line AA in FIG. 1 when the electromagnetic sounding body is incorporated in a body case such as a cellular phone.
FIG. 7 is a perspective view showing another embodiment of the electromagnetic sounding body according to the present invention.
8 is a perspective view of the packing in FIG. 7 as seen from the back side. FIG.
FIG. 9 is a perspective view showing a combination of a conventional electromagnetic sounding body and packing.
FIG. 10 is a conceptual diagram when a conventional electromagnetic sounding body is incorporated in a body case such as a mobile phone.
11 is a cross-sectional view taken along the line DD of FIG.
[Explanation of symbols]
11 Buzzer (electromagnetic sound generator)
12 Casing 15 Sound emission hole 16 Engagement portion 17 Engagement protrusion 17a First engagement wall 17b Second engagement wall 18 Engagement groove 21 Packing (sound leakage prevention member)
23 engaged portion 24 engaged groove 25 engaged protrusion

Claims

In an electromagnetic type sounding body comprising a thin casing having a sounding portion inside, a sound emitting hole opened in the casing, and a sound leakage preventing member disposed on the front side of the sound emitting hole,
While providing the engaging portion projecting forwardly from the sound emission hole in the casing, the engaged portion fixed lump to a difference in the engaging portion provided on the sound leakage prevention member,
The engaging portions are provided on both the left and right sides of the sound emitting hole, and a first engaging wall extending forward from the left and right ends of the sound emitting hole and a second extending outward from the tip of the first engaging wall, respectively. An engagement projection formed in a substantially L-shaped cross section on the engagement wall, and an engagement groove formed between the engagement projection and the wall surface of the casing,
The electromagnetic sounding body , wherein the engaged portion has an engaged groove into which the engaging protrusion fits and an engaged protrusion to fit into the engaging groove .

The first engagement wall positions the left and right direction of the sound leakage prevention member when the sound leakage prevention member is inserted, and the second engagement wall is formed of the sound leakage prevention member when the sound leakage prevention member is inserted. electromagnetic sounding body according to claim 1, wherein for positioning the front-rear direction.