JPH0549089A - Directivity dynamic microphone unit - Google Patents

Directivity dynamic microphone unit

Info

Publication number
JPH0549089A
JPH0549089A JP20783491A JP20783491A JPH0549089A JP H0549089 A JPH0549089 A JP H0549089A JP 20783491 A JP20783491 A JP 20783491A JP 20783491 A JP20783491 A JP 20783491A JP H0549089 A JPH0549089 A JP H0549089A
Authority
JP
Japan
Prior art keywords
acoustic
yoke
equalizer
microphone unit
dynamic microphone
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP20783491A
Other languages
Japanese (ja)
Inventor
Masayoshi Hojo
正義 北條
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Holdings Corp
Original Assignee
Matsushita Electric Industrial Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Priority to JP20783491A priority Critical patent/JPH0549089A/en
Publication of JPH0549089A publication Critical patent/JPH0549089A/en
Pending legal-status Critical Current

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  • Obtaining Desirable Characteristics In Audible-Bandwidth Transducers (AREA)

Abstract

PURPOSE:To realize the directivity dynamic microphone unit in which the frequency characteristic is easily adjusted and a synthetic resin case is not required. CONSTITUTION:A sound hole is provided to the inside of a disk of an equalizer, a projection is provided to the lower part of the outer circumference of the disk and a notch is provided to part of the projection. As to an acoustic yoke 14 a guard and plural recessed parts are provided to the cylindrical upper outer circumference and a magnetic yoke is provided in the inside of the cylinder. Then the notch of the equalizer 9 is mated to as to be overlapped with part of the recessed part of the acoustic yoke 14. Furthermore, a phase shift circuit acoustic terminal 16 formed with the acoustic yoke 14 and the equalizer 9 is covered by an acoustic resistance member 6 made of a woven cloth or a synthetic resin unwoven cloth adhered to a double-side adhesive tape 10 subject to hole-make processing to only the part of the phase shift circuit acoustic terminal 16. Then the end of the acoustic resistive member 6 is fitted to be located to the notch of the equalizer 9.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明はボ−カル及び拡声を主用
途とする指向性ダイナミックマイクロホンユニットに関
するものである。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a directional dynamic microphone unit mainly used for vocal and loud sound.

【0002】[0002]

【従来の技術】図5は従来の指向性ダイナミックマイク
ロホンユニットの断面図を示すものである。図5におい
て、1は円板状の振動板、2は円筒状のボイスコイル
で、振動板1に貼り付けられている。3は円筒状の磁気
ヨークで、外側の合成樹脂と一体樹脂成型されている。
また、磁気ヨーク3は振動板1の外周と接着固定してい
る。4は筒状の合成樹脂ケース、5は磁気ヨーク3とケ
ース4との間に形成された内部気室、6は織布又は合成
繊維不織布からなる音響抵抗材で、磁気ヨーク3の外側
の合成樹脂とケースとの外周全体を貼り合わせるように
接着固定されている。7は自由音場と内部気室とをつな
げる移相回路音響端子で、磁気ヨーク3の合成樹脂の外
枠に切り欠き状に形成されたものである。8は間隙で、
ケース4に凹部を設け、この凹部と音響抵抗材6の間に
形成するものである。9は筒状のイコライザで、この内
面には複数の音孔が形成され、また底部外周と磁気ヨー
ク3とは接着固定されている。
2. Description of the Related Art FIG. 5 is a sectional view of a conventional directional dynamic microphone unit. In FIG. 5, reference numeral 1 is a disk-shaped diaphragm, and 2 is a cylindrical voice coil, which is attached to the diaphragm 1. Reference numeral 3 is a cylindrical magnetic yoke, which is molded integrally with the outer synthetic resin.
Further, the magnetic yoke 3 is adhesively fixed to the outer periphery of the diaphragm 1. Reference numeral 4 is a cylindrical synthetic resin case, 5 is an internal air chamber formed between the magnetic yoke 3 and the case 4, and 6 is an acoustic resistance material made of woven cloth or synthetic fiber nonwoven cloth. The resin and the case are adhered and fixed so that the entire outer periphery of the case is attached. Reference numeral 7 denotes a phase-shifting circuit acoustic terminal that connects the free sound field and the internal air chamber, and is formed in a notch shape in the outer frame of the synthetic resin of the magnetic yoke 3. 8 is a gap,
The case 4 is provided with a recess, and is formed between the recess and the acoustic resistance material 6. Reference numeral 9 denotes a cylindrical equalizer, and a plurality of sound holes are formed on the inner surface of the equalizer, and the outer circumference of the bottom portion and the magnetic yoke 3 are bonded and fixed.

【0003】上記従来例の構造にける周波数特性は、振
動板1のスチフネス、振動板1に貼付けられたボイスコ
イル2の質量、内部気室5の等価質量、磁気ヨ−ク3及
び合成樹脂ケ−ス4にて形成された移相回路音響端子7
の一部に設けられた間隙8の上に音響抵抗材6を貼付け
ることにより付加質量をなす間隙8の付加質量によって
決定されもので、このときの共振周波数についての関係
式は(数1)のようになる。
The frequency characteristics in the structure of the above-mentioned conventional example are as follows: the stiffness of the diaphragm 1, the mass of the voice coil 2 attached to the diaphragm 1, the equivalent mass of the internal air chamber 5, the magnetic yoke 3, and the synthetic resin case. -Phase shift circuit acoustic terminal 7 formed by
It is determined by the additional mass of the gap 8 that forms the additional mass by pasting the acoustic resistance material 6 on the gap 8 provided in a part of the above. The relational expression for the resonance frequency at this time is (Equation 1) become that way.

【0004】[0004]

【数1】 [Equation 1]

【0005】したがって、上記のスチフネス、質量等を
設定することにより所望の特性を得ることができる。
Therefore, desired characteristics can be obtained by setting the above-mentioned stiffness, mass and the like.

【0006】[0006]

【発明が解決しようとする課題】しかしながら、上記従
来の指向性ダイナミックマイクロホンユニットの構造に
おいて、製造組み立て後に周波数特性を調整する場合
は、磁気ヨ−ク3及び合成樹脂ケ−ス4にて形成された
移相回路音響端子7の一部に設けられた間隙8の上に音
響抵抗材6を貼付けることにより付加質量をなす間隙8
の付加質量を調整している。しかしながら、製造組み立
て後に音響抵抗材6の僅かな貼り付け方を調整すること
は非常に困難であり、音響抵抗材6を接着固定してしま
ってから間隙8の調整をすることも非常に作業性がしに
くいという問題があった。
However, in the structure of the conventional directional dynamic microphone unit described above, when the frequency characteristic is adjusted after manufacturing and assembling, it is formed by the magnetic yoke 3 and the synthetic resin case 4. The gap 8 which forms an additional mass by pasting the acoustic resistance material 6 on the gap 8 provided in a part of the phase shift circuit acoustic terminal 7
The additional mass of is adjusted. However, it is very difficult to adjust a slight attachment method of the acoustic resistance material 6 after manufacturing and assembling, and it is also very workable to adjust the gap 8 after the acoustic resistance material 6 is adhesively fixed. There was a problem that it was difficult to do.

【0007】さらに、周波数特性について(数1)の関
係があるので、内部気室5の等価質量と間隙8の付加質
量とは、相互の和によって表されるので、内部気室5の
等価質量が大きい場合、間隙8の調整をおこなっても周
波数特性を大きく変動することができないという問題が
あった。
Further, since the frequency characteristic has the relationship of (Equation 1), the equivalent mass of the internal air chamber 5 and the added mass of the gap 8 are represented by the sum of each other. When is large, there is a problem that the frequency characteristic cannot be largely changed even if the gap 8 is adjusted.

【0008】本発明はこのような従来の問題を解決する
ものであり、周波数特性を容易に調整できる優れた指向
性ダイナミックマイクロホンユニットを提供することを
目的とするものである。
The present invention solves such a conventional problem, and an object of the present invention is to provide an excellent directional dynamic microphone unit whose frequency characteristics can be easily adjusted.

【0009】[0009]

【課題を解決するための手段】本発明は上記目的を達成
するために、音孔を有する円板の下部外周に凸部を設
け、この凸部の一部に切り欠き部を設けたイコライザ
と、上記凸部の内面に接し、固定されている振動板と、
筒状の上部外周に鍔及び複数の凹部を設け、上記筒状内
部に磁気ヨークを設けた音響ヨーク部と、上記イコライ
ザの切り欠き部が上記音響ヨークの凹部の一部分と重な
るように勘合した状態で、この凹部を覆うように取りつ
けられた音響抵抗材とを設けたものである。
In order to achieve the above object, the present invention provides an equalizer in which a convex portion is provided on the lower outer periphery of a disk having a sound hole, and a cutout portion is provided in a part of the convex portion. , A diaphragm that is in contact with the inner surface of the convex portion and is fixed,
A state in which a flange and a plurality of recesses are provided on the outer periphery of a tubular shape, and an acoustic yoke portion provided with a magnetic yoke inside the tubular portion and a cutout portion of the equalizer are fitted so as to overlap a part of the concave portion of the acoustic yoke. Then, the acoustic resistance material attached so as to cover the concave portion is provided.

【0010】[0010]

【作用】したがって本発明によれば、イコライザの凸部
の一部に切り欠き部を設け、さらに振動板をこのイコラ
イザに取りつけ、また音響ヨーク部に凹部を設け、上記
イコライザの切り欠き部が上記音響ヨークの凹部の一部
分と重なるように勘合した状態で、音響抵抗材によって
上記凹部を覆うので、従来のケース部をなくすことがで
き、内部気室を大幅に減らすことができるので、部品点
数を減らし、周波数特性の調整を容易にできるという効
果を有する。
Therefore, according to the present invention, the notch is provided in a part of the convex portion of the equalizer, the diaphragm is attached to the equalizer, and the concave portion is provided in the acoustic yoke portion. Since the concave portion is covered with the acoustic resistance material while being fitted so as to overlap with a part of the concave portion of the acoustic yoke, the conventional case portion can be eliminated and the internal air chamber can be significantly reduced. The effect is that the frequency characteristics can be reduced and the frequency characteristics can be easily adjusted.

【0011】[0011]

【実施例】図1乃至図3は本発明の実施例を示すもので
あり、図1は本発明の実施例における指向性ダイナミッ
クマイクロホンユニットの断面図、図2は同指向性ダイ
ナミックマイクロホンユニットの斜視図である。図3は
同指向性ダイナミックマイクロホンユニットの一部分解
斜視図である。図1乃至図3において、1は振動板、2
はボイスコイルであり、音響的信号を受け振動板1に貼
付けられているボイスコイル2を変位させることにより
ボイスコイル2に出力信号を誘起させるものである。9
はイコライザで、円板状の内部に音孔を有し、円板状外
周下部に凸部を設け、この凸部の一部分に切り欠き部を
設けたものである。そして、この凸部内面に振動板1の
外周が接着固定されている。12は磁気片、13は磁
石、14は音響ヨークで、筒状の上部外周に鍔及び複数
の凹部を設け、上記筒状内部に磁気ヨークを設けたもの
で、磁気ヨークの上部に磁気片12、磁石13が接着固
定されている。また、磁気片12、磁石13、音響ヨー
ク18の中央部には音孔が形成されている。6は織布又
は合成繊維不織布からなる音響抵抗材である。そして、
音響ヨ−ク14の鍔とイコライザ9の凸部とを勘合さ
せ、イコライザ9の切り欠き部が音響ヨークの凹部の一
部分と重なるようにした状態で、音響抵抗材6はイコラ
イザ9の切り欠き部の一部分を除いて両面テープ10に
よって貼り付けられるものである。15は間隙で、イコ
ライザ9の切り欠き部と音響抵抗材6の端部17によっ
て形成されたものである。16は移相回路音響端子で、
イコライザ9の凸部と音響ヨーク14の凹部と音響抵抗
材6によって囲まれて形成されるものであり、図3に示
すように、移相回路音響端子16のうち1つについては
イコライザ9の切り欠き部を介して間隙15に通じ、自
由音場に直接つながっているものである。ここで、移相
回路音響端子16が音響抵抗材6を介し、自由音場と通
じるように、移相回路音響端子16に接する部分の両面
テープ10はカットされている。18は、後部音響抵抗
で、音響ヨーク14の中央部の音孔を覆うように取りつ
けられているものである。
1 to 3 show an embodiment of the present invention. FIG. 1 is a sectional view of a directional dynamic microphone unit according to an embodiment of the present invention, and FIG. 2 is a perspective view of the same directional dynamic microphone unit. It is a figure. FIG. 3 is a partially exploded perspective view of the directional dynamic microphone unit. 1 to 3, 1 is a diaphragm, 2
Is a voice coil, which induces an output signal in the voice coil 2 by displacing the voice coil 2 attached to the diaphragm 1 by receiving an acoustic signal. 9
Is an equalizer, which has a sound hole inside a disc, a protrusion is provided on the lower periphery of the disc, and a notch is provided in a part of the protrusion. The outer periphery of the diaphragm 1 is adhered and fixed to the inner surface of the convex portion. Reference numeral 12 is a magnetic piece, 13 is a magnet, and 14 is an acoustic yoke. A collar and a plurality of recesses are provided on the outer periphery of a cylindrical upper portion, and a magnetic yoke is provided inside the cylindrical portion. The magnet 13 is fixed by adhesion. Further, a sound hole is formed in the central portion of the magnetic piece 12, the magnet 13, and the acoustic yoke 18. Reference numeral 6 is an acoustic resistance material made of woven fabric or synthetic fiber nonwoven fabric. And
With the flange of the acoustic yoke 14 and the convex portion of the equalizer 9 fitted together so that the cutout portion of the equalizer 9 overlaps a part of the concave portion of the acoustic yoke, the acoustic resistance material 6 has the cutout portion of the equalizer 9. It is attached by the double-sided tape 10 except for a part. A gap 15 is formed by the cutout portion of the equalizer 9 and the end portion 17 of the acoustic resistance material 6. 16 is a phase shift circuit acoustic terminal,
It is formed by being surrounded by the convex portion of the equalizer 9, the concave portion of the acoustic yoke 14, and the acoustic resistance material 6. As shown in FIG. 3, one of the phase shift circuit acoustic terminals 16 is cut by the equalizer 9. The gap 15 is connected to the free sound field via the notch. Here, the double-sided tape 10 at the portion in contact with the phase-shift circuit acoustic terminal 16 is cut so that the phase-shift circuit acoustic terminal 16 communicates with the free sound field through the acoustic resistance material 6. Reference numeral 18 denotes a rear acoustic resistance, which is attached so as to cover the sound hole in the central portion of the acoustic yoke 14.

【0012】上記実施例の構造によれば、周波数特性の
要素である、振動板1のスチフネス、振動板1に貼付け
られたボイスコイル2の質量、内部気室の等価質量、移
相回路音響端子16の一部に設けられた間隙15の付加
質量のうち、内部気室の等価質量は、振動板1下部の内
部気室が、移相回路音響端子16などの構造により、非
常に容積を小さくできるので、内部気室の等価質量の変
動に対する周波数特性の影響は小さくなり、逆に間隙1
5の付加質量の変動に対する周波数特性の影響は大きく
なる。したがって、周波数特性を調整する場合には、イ
コライザ9の切り欠き部と両面テープで固定された音響
抵抗材6の端部17によって形成される間隙15を少し
調整することによって、比較的容易に周波数特性の調整
をすることができる。
According to the structure of the above embodiment, the stiffness of the diaphragm 1, the mass of the voice coil 2 attached to the diaphragm 1, the equivalent mass of the internal air chamber, the phase shift circuit acoustic terminal, which are the elements of the frequency characteristic, are obtained. Among the added masses of the gap 15 provided in a part of 16, the equivalent mass of the internal air chamber has a very small volume because the internal air chamber under the diaphragm 1 has a structure such as the phase shift circuit acoustic terminal 16. Therefore, the influence of the frequency characteristic on the variation of the equivalent mass of the internal air chamber becomes small, and conversely the gap 1
The influence of the frequency characteristic on the fluctuation of the additional mass of No. 5 becomes large. Therefore, when adjusting the frequency characteristic, the frequency can be relatively easily adjusted by slightly adjusting the gap 15 formed by the cutout portion of the equalizer 9 and the end portion 17 of the acoustic resistance material 6 fixed by the double-sided tape. The characteristics can be adjusted.

【0013】例えば、図4に示すように、本実施例の構
成による出力周波数特性を間隙を設けないもの(図面の
一点破線)と間隙を設けたもの(図面の実線)である。
図4において、指向性ダイナミックマイクロホンのイコ
ライザの音孔開口方向を0°としたときの0°の出力周
波数は、間隙15を設けたものは、間隙15を設けない
ものに比べて明らかに低域の周波数特性が改善され、1
80°の出力周波数は、間隙15を設けたものは、間隙
15を設けないものに比べて明らかに低域の周波数特性
が落ちるので、結果として指向性の増し、低域の周波数特
性が改善された指向性ダイナミックマイクロホンユニッ
トが得られる。また、図4においては、間隙のある、な
しでの違いを示したが、0°方向に対する周波数特性の
微妙な調整も以上の説明から容易にできるという効果を
有する。
For example, as shown in FIG. 4, the output frequency characteristics according to the structure of the present embodiment are one in which no gap is provided (one-dot broken line in the drawing) and one in which a gap is provided (solid line in the drawing).
In FIG. 4, the output frequency of 0 ° when the sound hole opening direction of the equalizer of the directional dynamic microphone is 0 ° is clearly lower in the frequency range with the gap 15 than in the case without the gap 15. The frequency characteristics of are improved and
With respect to the output frequency of 80 °, the frequency characteristics in the low frequency range are obviously lower in the case where the gap 15 is provided than in the case where the clearance 15 is not provided. As a result, the directivity is increased and the frequency characteristic in the low frequency range is improved. A directional dynamic microphone unit is obtained. Further, in FIG. 4, the difference between with and without a gap is shown, but there is an effect that delicate adjustment of the frequency characteristic in the 0 ° direction can be easily performed from the above description.

【0014】また、音響ヨークによって、磁気ヨーク、
移相回路音響端子、ケースを一体樹脂成型することがで
きるので低価格化がなされるという効果を有する。
Further, the acoustic yoke allows the magnetic yoke,
Since the phase-shift circuit acoustic terminal and the case can be integrally resin-molded, the cost can be reduced.

【0015】[0015]

【発明の効果】本発明は上記実施例より明らかなよう
に、音響ヨ−ク部とイコライザとの継部に間隙を設け、
音響抵抗材にて覆うことにより自由音場に通じる付加質
量を容易に決定することができ、比較的容易に所望の周
波数特性を調整することができるという効果を有する。
As is apparent from the above embodiment, the present invention provides a gap at the joint between the acoustic yoke and the equalizer,
By covering with the acoustic resistance material, the additional mass leading to the free sound field can be easily determined, and the desired frequency characteristic can be adjusted relatively easily.

【0016】また、音響ヨーク部によって磁気ヨーク、
移相回路音響端子、ケースを一体樹脂成型することがで
きるので低価格化がなされるという効果を有する。
Further, the acoustic yoke portion is used for the magnetic yoke,
Since the phase-shift circuit acoustic terminal and the case can be integrally resin-molded, the cost can be reduced.

【図面の簡単な説明】[Brief description of drawings]

【図1】本発明の実施例に於ける指向性ダイナミックマ
イクロホンユニットの断面図
FIG. 1 is a sectional view of a directional dynamic microphone unit according to an embodiment of the present invention.

【図2】同指向性ダイナミックマイクロホンユニットの
斜視図
FIG. 2 is a perspective view of the directional dynamic microphone unit.

【図3】同指向性ダイナミックマイクロホンユニットの
一部分解斜視図同指向性ダイナミックマイクロホンユニ
ットの出力周波数特性図
FIG. 3 is a partially exploded perspective view of the directional dynamic microphone unit, showing an output frequency characteristic of the directional dynamic microphone unit.

【図4】同指向性ダイナミックマイクロホンユニットの
出力周波数特性図
FIG. 4 is an output frequency characteristic diagram of the same directional dynamic microphone unit.

【図5】従来の指向性ダイナミックマイクロホンユニッ
トの断面図
FIG. 5 is a sectional view of a conventional directional dynamic microphone unit.

【符号の説明】[Explanation of symbols]

1 振動板 2 ボイスコイル 6 音響抵抗材 9 イコライザ 10 両面粘着テ−プ 12 磁極片 13 磁石 14 音響ヨーク 15 間隙 16 移相回路音響端子 DESCRIPTION OF SYMBOLS 1 Vibration plate 2 Voice coil 6 Acoustic resistance material 9 Equalizer 10 Double-sided adhesive tape 12 Magnetic pole piece 13 Magnet 14 Acoustic yoke 15 Gap 16 Phase-shift circuit acoustic terminal

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】 音孔を有する円板の下部外周に凸部を設
け、この凸部の一部に切り欠き部を設けたイコライザ
と、上記凸部の内面に接し、固定されている振動板と、
この振動板に取りつけられたボイスコイルと、筒状の上
部外周に鍔及び複数の凹部を設け、この筒状内部に磁気
ヨークを設けた音響ヨーク部と、この音響ヨーク部に取
りつけられた磁石及び磁気片と、上記イコライザの切り
欠き部が上記音響ヨークの凹部の一部と重なるように勘
合した状態で、この凹部を覆うように取りつけられた音
響抵抗材とから構成される指向性ダイナミックマイクロ
ホンユニット。
1. An equalizer in which a convex portion is provided on a lower outer periphery of a disk having a sound hole, and a cutout portion is provided in a part of the convex portion, and a diaphragm which is in contact with and fixed to an inner surface of the convex portion. When,
A voice coil attached to the diaphragm, an acoustic yoke portion provided with a collar and a plurality of recesses on the outer periphery of a cylindrical upper portion, and a magnetic yoke provided inside the tubular portion, a magnet attached to the acoustic yoke portion, and A directional dynamic microphone unit composed of a magnetic piece and an acoustic resistance material attached so as to cover the concave portion of the acoustic yoke in a state where the cutout portion of the equalizer is fitted so as to overlap with the concave portion of the acoustic yoke. ..
JP20783491A 1991-08-20 1991-08-20 Directivity dynamic microphone unit Pending JPH0549089A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP20783491A JPH0549089A (en) 1991-08-20 1991-08-20 Directivity dynamic microphone unit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP20783491A JPH0549089A (en) 1991-08-20 1991-08-20 Directivity dynamic microphone unit

Publications (1)

Publication Number Publication Date
JPH0549089A true JPH0549089A (en) 1993-02-26

Family

ID=16546294

Family Applications (1)

Application Number Title Priority Date Filing Date
JP20783491A Pending JPH0549089A (en) 1991-08-20 1991-08-20 Directivity dynamic microphone unit

Country Status (1)

Country Link
JP (1) JPH0549089A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006203468A (en) * 2005-01-19 2006-08-03 Nippon Denon Kk Drip-proof type unidirectional microphone unit

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006203468A (en) * 2005-01-19 2006-08-03 Nippon Denon Kk Drip-proof type unidirectional microphone unit

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