JP3324876B2 - Probe microphone - Google Patents
Probe microphoneInfo
- Publication number
- JP3324876B2 JP3324876B2 JP18664494A JP18664494A JP3324876B2 JP 3324876 B2 JP3324876 B2 JP 3324876B2 JP 18664494 A JP18664494 A JP 18664494A JP 18664494 A JP18664494 A JP 18664494A JP 3324876 B2 JP3324876 B2 JP 3324876B2
- Authority
- JP
- Japan
- Prior art keywords
- absorbing material
- sound absorbing
- microphone
- probe
- filled
- 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.)
- Expired - Fee Related
Links
Description
【０００１】[0001]
【産業上の利用分野】本発明は、例えば高温環境下にお
いて音圧を測定するのに使用するプローブマイクロホン
に関し、特にその周波数応答特性の改善に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a probe microphone used for measuring sound pressure in, for example, a high-temperature environment, and more particularly to an improvement in a frequency response characteristic thereof.
【０００２】[0002]
【従来の技術】一般に、プローブマイクロホンには、マ
イクロホンカートリッジの先端に細長いプローブ管を接
続したものがある。しかし、このようなプローブマイク
ロホンでは、プローブ管の内部空間が、その空間形状固
有の共振周波数を有するため、その共振周波数において
周波数応答のピークができる。このピークを解消するた
め、従来、例えば特開平３−２２６９８号公報に開示さ
れているような技術があった。これは、マイクロホンを
収容した円板の前面に、マイクロホンと連通する凹所を
設け、この凹所にプローブ管を接続すると共に、長さの
それぞれ異なる複数のインピーダンス整合管を凹所に接
続したものである。これらインピーダンス整合管は、長
さが長いものであるので、円板の後方にコイル状に巻回
して配置されている。2. Description of the Related Art Generally, some probe microphones have an elongated probe tube connected to the tip of a microphone cartridge. However, in such a probe microphone, since the internal space of the probe tube has a resonance frequency inherent in the space shape, a peak of the frequency response occurs at the resonance frequency. In order to eliminate this peak, there has been a technique as disclosed in, for example, JP-A-3-22698. This is one in which a concave portion communicating with the microphone is provided on the front surface of the disk containing the microphone, a probe tube is connected to the concave portion, and a plurality of impedance matching tubes having different lengths are connected to the concave portion. It is. Since these impedance matching tubes have a long length, they are wound in a coil shape behind a disk.
【０００３】[0003]
【発明が解決しようとする課題】しかし、特開平３−２
２６９８号公報の技術では、長さの異なる複数のインピ
ーダンス整合管を使用しなければならず、しかも円板の
後方にこれら複数のインピーダンス整合管をコイル状に
巻回して配置しなければならないという複雑な構造であ
るので、製造コストが高くなるという問題点があった。
さらに、コイル状に巻回した複数のインピーダンス整合
管を配置する空間を必要とするので、装置全体が大型に
なるという問題点もあった。However, Japanese Patent Laid-Open Publication No. Hei 3-2
In the technique disclosed in Japanese Patent No. 2698, a plurality of impedance matching tubes having different lengths must be used, and furthermore, the plurality of impedance matching tubes must be wound in a coil shape and arranged behind a disk. Because of the complicated structure, there is a problem that the manufacturing cost is increased.
Further, since a space for disposing a plurality of impedance matching tubes wound in a coil shape is required, there is a problem that the entire device becomes large.
【０００４】[0004]
【課題を解決するための手段】上記の問題点を解決する
ために、本発明は、マイクロホンと、プローブとを、具
備している。プローブは、基部と、これに連なる膨大部
とを備えている。プローブでは、基部の長さ方向に沿う
全域と、基部と膨大部との境界部から膨大部の中途まで
内孔が形成され、残りの膨大部は、マイクロホンが取り
付けられているマイクロホン取付部とされている。膨大
部内における内孔とマイクロホン取付部との間に、吸音
材が充填されている吸音材充填部が形成されている。こ
の充填部は、一方の側で隣接している内孔の内径よりも
大きく、他方の側で隣接しているマイクロホン取付部の
内径よりも小さくされている。 SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention comprises a microphone and a probe.
I have it. The probe consists of a base and
And In the probe, along the length of the base
The entire area, from the boundary between the base and the magnum, to the middle of the magnum
An inner hole is formed, and the remaining enormous part is taken by the microphone.
The attached microphone mounting portion is provided. Huge
Between the inner hole and the microphone mounting part
A sound-absorbing material-filled portion filled with a material is formed. This
Of the inner hole is larger than the inner diameter of the adjacent hole on one side.
Large, adjacent microphone mounting area on the other side
It is smaller than the inner diameter.
【０００５】[0005]
【０００６】[0006]
【０００７】[0007]
【作用】本第１の発明では、マイクロホンが取り付けら
れているプローブ管内に吸音材を充填しているので、特
定の周波数における周波数応答のピークが生じない。According to the first aspect of the present invention, since the sound absorbing material is filled in the probe tube to which the microphone is attached, a peak of the frequency response at a specific frequency does not occur.
【０００８】[0008]
【０００９】また、吸音材充填部の両端には、それぞれ
段が形成される。従って、これら段の間に吸音材を充填
することによって、確実に所定量の吸音材を充填するこ
とができる。 [0009] At both ends of the sound absorbing material filling section, stage it is formed. Therefore, by filling the sound absorbing material between these steps, a predetermined amount of the sound absorbing material can be reliably filled.
【００１０】[0010]
【実施例】図１に本発明の参考例を示す。この参考例の
プローブマイクロホン１は、プローブ管２を有してい
る。このプローブ管２は、例えばアルミニウムまたはス
テンレス製のものであり、長さ方向に直角な断面が円形
である円管状に形成された基部４を備えている。この基
部４に連ねて膨大部６が形成されている。この膨大部６
も、長さ方向に直角な断面が円形であり、外径が基部４
よりも大きく形成されている。FIG. 1 shows a reference example of the present invention . The probe microphone 1 of this reference example has a probe tube 2. The probe tube 2 is made of, for example, aluminum or stainless steel, and has a base 4 formed in a tubular shape having a circular cross section perpendicular to the length direction. An enlarged portion 6 is formed in connection with the base portion 4. This huge part 6
Also, the cross section perpendicular to the length direction is circular, and the outer diameter is
It is formed larger than.
【００１１】基部４の長さ方向に沿ってその全域と、基
部４と膨大部６との境界から膨大部６の中途までには、
一定の内径ｄ１の内孔７が形成され、残りの膨大部６の
内径ｄ２は、内径ｄ１よりも大きくされている。この内
径ｄ２の部分は、マイクロホン取付部９とされ、ここに
例えばコンデンサマイクロホン８が取り付けられてい
る。このマイクロホン取付部９では、マイクロホン８
は、その先端部が膨大部６における内孔７との境界まで
進入している。In the entire area along the length direction of the base 4 and between the boundary between the base 4 and the enlarged section 6 and halfway through the enlarged section 6,
The inner hole 7 having a constant inner diameter d1 is formed, and the inner diameter d2 of the remaining enlarged portion 6 is larger than the inner diameter d1. The part with the inner diameter d2 is used as a microphone mounting part 9, where, for example, a condenser microphone 8 is mounted. In the microphone mounting section 9, the microphone 8
, The tip of which has entered the boundary with the inner hole 7 in the enlarged portion 6.
【００１２】そして、このマイクロホン８の先端と、基
部４及び膨大部６の境界との間の内孔７には、例えばフ
ェルトまたはガラス繊維製の吸音材１０が、膨大部６及
び基部４の長さ方向に直角な方向の断面を満たすように
充填されている。A sound absorbing material 10 made of, for example, felt or glass fiber is provided in the inner hole 7 between the distal end of the microphone 8 and the boundary between the base 4 and the enlarged portion 6. Is filled so as to fill a cross section in a direction perpendicular to the vertical direction.
【００１３】このようなプローブマイクロホン１は、図
２に示すように、排気ダクト１２を通過する例えば摂氏
４００度の高温または腐食性のガスの音圧を測定するた
めに、排気ダクト１２に設けた導出管１４の部分に、プ
ローブ管２の基部４を取り付けて使用する。なお、導出
管１４では、ガスの温度は、約摂氏７０度にまで低下し
ている。As shown in FIG. 2, such a probe microphone 1 is provided in the exhaust duct 12 for measuring the sound pressure of a high-temperature or corrosive gas of, for example, 400 degrees Celsius passing through the exhaust duct 12. The base 4 of the probe tube 2 is used by attaching it to the outlet tube 14. In the outlet pipe 14, the temperature of the gas has dropped to about 70 degrees Celsius.
【００１４】このようにプローブ管２内に適量の吸音材
１０を充填するという簡単な構成によって、プローブ管
２固有の共振周波数において、周波数応答のピークを解
消することができ、所要の周波数帯域にわたって滑らか
な周波数応答を得ることができる。従って、長さの異な
る複数のインピーダンス整合管を使用する必要がなく、
製造コストを低下させることができる上に、小型化を図
ることができる。With such a simple structure in which the probe tube 2 is filled with an appropriate amount of the sound absorbing material 10, the peak of the frequency response can be eliminated at the resonance frequency unique to the probe tube 2, and the probe can be used over a required frequency band. A smooth frequency response can be obtained. Therefore, it is not necessary to use a plurality of impedance matching tubes having different lengths,
The manufacturing cost can be reduced and the size can be reduced.
【００１５】吸音材１０の挿入量が適量であれば、上述
したように滑らかな周波数応答特性を示すが、吸音材１
０が適量よりも不足すると、ピークが充分に解消されな
い。また、吸音材１０が多すぎると、高い周波数帯域に
おいて、周波数応答が低くなる。よって、吸音材１０の
量を適量にする必要がある。If the insertion amount of the sound absorbing material 10 is appropriate, the frequency response characteristics are smooth as described above.
If 0 is less than the appropriate amount, the peak will not be sufficiently eliminated. If the amount of the sound absorbing material 10 is too large, the frequency response is low in a high frequency band. Therefore, it is necessary to make the amount of the sound absorbing material 10 an appropriate amount.
【００１６】この吸音材１０の適量は、実験的に定める
が、たとえ適量が決定されたとしても、この実施例で
は、吸音材１０は、内径がｄ１と一定の内孔７内に充填
されているので、充填していく際に、どの程度に吸音材
１０を充填したかがわかりにくく、完全に適量に吸音材
を充填しにくい。また、たとえ適量の吸音材１０を充填
できたとしても、内孔７に充填されているので、プロー
ブ管２が例えば振動を受けると、その振動によって、吸
音材１０が、図１の左端側に移動し、ついには左端部分
から抜け落ちる可能性もある。The appropriate amount of the sound absorbing material 10 is determined experimentally. Even if the appropriate amount is determined, in this embodiment, the sound absorbing material 10 is filled in the inner hole 7 having an inner diameter d1 and a constant value. Therefore, when filling, it is difficult to know how much the sound absorbing material 10 is filled, and it is difficult to completely fill the sound absorbing material with an appropriate amount. Even if a proper amount of the sound absorbing material 10 can be filled, since the inner hole 7 is filled, when the probe tube 2 receives, for example, vibration, the vibration causes the sound absorbing material 10 to move to the left end side in FIG. It may move and eventually fall off the left edge.
【００１７】図３に示す本発明の１実施例のプローブマ
イクロホン１ａは、これらの問題を解消したものであ
る。プローブ管２ａの膨大部６内における内孔７とマイ
クロホン取付部９との間に、新たに吸音材充填部１６が
形成されている。なお、他の構成は、図１の参考例と同
様であるので、同一符号を付して、その説明を省略す
る。 The probe microphone 1a according to one embodiment of the present invention shown in FIG. 3 solves these problems. A sound absorbing material filling portion 16 is newly formed between the inner hole 7 and the microphone mounting portion 9 in the enlarged portion 6 of the probe tube 2a. The other configuration is the same as that of the reference example of FIG. 1, and therefore, the same reference numerals are given and the description thereof will be omitted.
【００１８】この吸音材充填部１６は、その内径ｄ３
が、吸音材充填部１６の一方の側で隣接している内孔７
の内径ｄ１よりも大きく、かつ吸音材充填部１６の他方
の側で隣接しているマイクロホン取付部９の内径ｄ２よ
りも小さくされている。従って、内孔７との境界に段が
形成されると共に、マイクロホン取付部９との間にも段
が形成されている。なお、この吸音材充填部１６の長さ
Ｌは、内径ｄ３との関係において吸音材１０の充填量
が、実験によって決定した適量となるように設定されて
いる。The sound absorbing material filling section 16 has an inner diameter d3
Are adjacent to one side of the sound absorbing material filling portion 16.
And smaller than the inner diameter d2 of the microphone mounting portion 9 adjacent to the other side of the sound absorbing material filling portion 16 on the other side. Accordingly, a step is formed at the boundary with the inner hole 7, and a step is formed between the microphone mounting portion 9 and the step. The length L of the sound absorbing material filling portion 16 is set such that the filling amount of the sound absorbing material 10 becomes an appropriate amount determined by experiment in relation to the inner diameter d3.
【００１９】このように内孔７と吸音材充填部１６との
境界に段があるので、吸音材１０をマイクロホン取付部
９側から充填した場合、吸音材１０は、この段を越え
て、内孔７側にまで充填されることはないし、使用中に
プローブ管１２ａが振動を受けても、吸音材１０が、こ
の段を乗り越えて、図３の左方に移動することもない。Since there is a step at the boundary between the inner hole 7 and the sound absorbing material filling portion 16 as described above, when the sound absorbing material 10 is filled from the microphone mounting portion 9 side, the sound absorbing material 10 goes over the step and The hole 7 is not filled, and even if the probe tube 12a is vibrated during use, the sound absorbing material 10 does not climb over this step and move to the left in FIG.
【００２０】さらに、この吸音材充填部１６とマイクロ
ホン取付部９との境界にも段があるので、マイクロホン
取付部９側から吸音材１０を充填する場合、この段まで
吸音材１０を充填することによって、適量の吸音材１０
を確実に充填できる。Furthermore, since there is a step at the boundary between the sound absorbing material filling portion 16 and the microphone mounting portion 9, when the sound absorbing material 10 is filled from the microphone mounting portion 9 side, the sound absorbing material 10 must be filled up to this level. The appropriate amount of the sound absorbing material 10
Can be reliably filled.
【００２１】なお、ｄ１とｄ３との差を余り大きくする
のは、好ましくはない。それは、次の理由による。内径
ｄ１である内孔７での空気の粒子速度をＶ１、内径ｄ３
の吸音材充填部１６での空気の粒子速度をＶ３とする
と、内径ｄ１、ｄ３と、Ｖ１、Ｖ３との間には、数１で
示す関係がある。It is not preferable to make the difference between d1 and d3 too large. It is for the following reasons. V1 is the particle velocity of air in the inner hole 7 having the inner diameter d1, and d3 is the inner diameter.
Assuming that the particle velocity of the air in the sound absorbing material filling section 16 is V3, there is a relationship expressed by Equation 1 between the inner diameters d1, d3 and V1, V3.
【数１】 π（ｄ１／２）2 ・Ｖ１＝π（ｄ３／２）2 ・Ｖ３ ここで、ｄ１とｄ３との差がかなり大きいと、Ｖ３がＶ
１に比べて小さくなる。吸音材１０による吸音効果は、
粒子速度の自乗に比例することが知られているので、Ｖ
３がＶ１に比べて小さくなりすぎると、周波数応答のピ
ークが充分に解消できなくなる。従って、上記のように
ｄ１とｄ３との差を余り大きくしない方がよい。実験の
結果、ｄ３とｄ１との比ｄ３／ｄ１は、２．５以内であ
るのが、望ましいことがわかった。Π (d1 / 2) 2 · V1 = π (d3 / 2) 2 · V3 Here, if the difference between d1 and d3 is considerably large, V3 becomes V
It is smaller than 1. The sound absorbing effect of the sound absorbing material 10 is as follows.
Since it is known to be proportional to the square of the particle velocity, V
If 3 is too small compared to V1, the peak of the frequency response cannot be sufficiently eliminated. Therefore, it is better not to make the difference between d1 and d3 too large as described above. As a result of the experiment, it was found that the ratio d3 / d1 of d3 and d1 was desirably within 2.5.
【００２２】図４は、本実施例における周波数応答特性
を示したもので、５０乃至８００Ｈｚとかなり広い周波
数帯において平坦な周波数特性を示している。FIG. 4 shows the frequency response characteristic in the present embodiment, and shows a flat frequency characteristic in a fairly wide frequency band of 50 to 800 Hz.
【００２３】図５は、本実施例において吸音材１０を除
去した状態における周波数応答特性を示したもので、１
５０Ｈｚ付近から周波数応答特性が立ち上がり、約８０
０Ｈｚ付近にピークが生じている。これは、上述したよ
うに、プローブ管２ａが固有の共振周波数を有している
からである。FIG. 5 shows the frequency response characteristics of this embodiment with the sound absorbing material 10 removed.
The frequency response characteristic rises from around 50 Hz,
A peak occurs near 0 Hz. This is because the probe tube 2a has a unique resonance frequency, as described above.
【００２４】図６は、本実施例において吸音材１０を少
量だけ、例えば内孔７と吸音材充填部１６との境界の段
から吸音材充填部１６の中途まで、充填した場合の周波
数応答特性を示したもので、吸音材１０が不足している
ので、ピークを完全に解消することができていない。FIG. 6 shows a frequency response characteristic when the sound absorbing material 10 is filled in a small amount, for example, from the step at the boundary between the inner hole 7 and the sound absorbing material filling portion 16 to the middle of the sound absorbing material filling portion 16 in the present embodiment. The peak cannot be completely eliminated because the sound absorbing material 10 is insufficient.
【００２５】図７は、本実施例において、吸音材１０を
適量よりも多く充填した場合、例えばマイクロホン取付
部９と吸音材充填部１０との境界の段から、吸音材充填
部１６と内孔７との境界を越えて内孔７内まで充填した
場合の周波数応答特性を示したもので、吸音材１０が過
多であるので、高い周波数、例えば２００Ｈｚ以上の周
波数において周波数応答が低下している。FIG. 7 shows that, in this embodiment, when the sound absorbing material 10 is filled more than an appropriate amount, for example, the sound absorbing material filling portion 16 7 shows a frequency response characteristic when the inside of the inner hole 7 is filled beyond the boundary with 7, and the frequency response is reduced at a high frequency, for example, a frequency of 200 Hz or more because the sound absorbing material 10 is excessive. .
【００２６】なお、これらの各周波数応答特性は、内径
ｄ１を３ｍｍ、内径ｄ２を１２．７ｍｍ、内径ｄ３を５
ｍｍ、吸音材充填部１６の長さＬを１３ｍｍ、基部４の
左端から吸音材充填部１６までの距離Ｌ１を３５ｍｍと
した場合のものである。The respective frequency response characteristics are as follows: the inner diameter d1 is 3 mm, the inner diameter d2 is 12.7 mm, and the inner diameter d3 is 5 mm.
mm, the length L of the sound absorbing material filling portion 16 is 13 mm, and the distance L1 from the left end of the base 4 to the sound absorbing material filling portion 16 is 35 mm.
【００２７】これらのように適量の吸音材１０を充填す
ることによって、周波数応答特性を広帯域にわたって平
坦にすることができ、段を上記のように設けたことによ
って、適量の吸音材１０を充填することができる。By filling an appropriate amount of the sound absorbing material 10 as described above, the frequency response characteristics can be flattened over a wide band, and by providing the steps as described above, the appropriate amount of the sound absorbing material 10 is filled. be able to.
【００２８】上記の実施例では、プローブ管２、２ａ
は、その長さ方向に直角な断面が円形のものを示した
が、他の形状のものを使用することもできる。また、上
記の両実施例では、プローブ管２、２ａは、膨大部６の
部分だけ外径が大きいものを使用したが、外径が一定
で、内径だけを、参考例のようにｄ１、ｄ２または本実
施例のようにｄ１、ｄ２、ｄ３としてもよい。In the above embodiment , the probe tubes 2, 2a
Has a circular cross section at right angles to its length, but other shapes may be used. Further, in both the above embodiments, the probe tubes 2 and 2a whose outer diameters are large only at the enlarged portion 6 are used, but the outer diameters are constant and only the inner diameters are d1 and d2 as in the reference example. Or real
As in the embodiment, d1, d2, and d3 may be used.
【００２９】[0029]
【発明の効果】以上のように、請求項１記載の発明によ
れば、吸音材をプローブ管内に充填しているので、プロ
ーブ管固有の共振周波数で生じる周波数応答特性のピー
クを抑圧することができる上に、構成が簡単であるので
容易に製造でき、かつ、コストを低下させることがで
き、しかも、小型化を図ることができる。さらに、吸音
材充填部の縦断面積は、この吸音材充填部に隣接する部
分の一方よりも大きく、隣接する他方の部分よりも小さ
く形成されているので、吸音材充填部の両端には、それ
ぞれ段が形成されている。従って、この段から段まで吸
音材を充填することによって、より確実に適量の吸音材
を充填することができる。As described above, according to the first aspect of the present invention, since the sound absorbing material is filled in the probe tube, it is possible to suppress the peak of the frequency response characteristic generated at the resonance frequency inherent in the probe tube. In addition to that, since the structure is simple, it can be easily manufactured, the cost can be reduced, and the size can be reduced. Furthermore, sound absorption
The longitudinal cross-sectional area of the sound-absorbing material filling portion is formed larger than one of the portions adjacent to the sound-absorbing material filling portion and smaller than the other adjacent portion, so that a step is formed at each end of the sound absorbing material filling portion. Have been. Therefore, by filling the sound absorbing material from one step to another, it is possible to more reliably fill an appropriate amount of the sound absorbing material.
【図１】本発明によるプローブマイクロホンの参考例の
縦断面図である。FIG. 1 is a longitudinal sectional view of a reference example of a probe microphone according to the present invention.
【図２】同参考例の使用状態を示す縦断面図である。FIG. 2 is a longitudinal sectional view showing a use state of the reference example .
【図３】同実施例の縦断面図である。FIG. 3 is a vertical sectional view of the embodiment .
【図４】同実施例の周波数応答特性図である。FIG. 4 is a frequency response characteristic diagram of the embodiment .
【図５】同実施例において吸音材を除去した状態の周波
数応答特性図である。5 is a frequency response characteristic view of a state in which removal of the Oite sound absorbing material in the embodiment.
【図６】同実施例において吸音材を少量充填した状態の
周波数応答特性図である。6 is a frequency response characteristic view of a state filled small amount Oite sound absorbing material in the embodiment.
【図７】同実施例において吸音材を多量に充填した状態
の周波数応答特性図である。7 is a frequency response characteristic view of a state where a large amount of filling the Oite sound absorbing material in the embodiment.
１ １ａ プローブマイクロホン ２ ２ａ プローブ管 ４ 基部 ６ 膨大部 ８ マイクロホン ９ マイクロホン取付部 １０ 吸音材 １６ 吸音材充填部 DESCRIPTION OF SYMBOLS 1 1a Probe microphone 2 2a Probe tube 4 Base 6 Enlarged part 8 Microphone 9 Microphone attachment part 10 Sound absorbing material 16 Sound absorbing material filling part
フロントページの続き (58)調査した分野(Int.Cl.7，ＤＢ名) H04R 1/34 320 G01H 3/00 Continuation of front page (58) Field surveyed (Int.Cl. 7 , DB name) H04R 1/34 320 G01H 3/00
Claims (1)
方向に沿う全域と、前記基部と前記膨大部との境界部か
ら前記膨大部の中途まで内孔が形成され、残りの前記膨
大部を前記マイクロホンが取り付けられているマイクロ
ホン取付部とし、前記膨大部内における前記内孔と前記
マイクロホン取付部との間に、吸音材が充填されている
吸音材充填部が形成され、この充填部は、一方の側で隣
接している前記内孔の内径よりも大きく、他方の側で隣
接している前記マイクロホン取付部の内径よりも小さく
されている プローブとを、 具備するプローブマイクロホン。1. A microphone comprising: a microphone; a base;
The entire area along the direction and the boundary between the base and the bulge
An inner hole is formed halfway through the bulging portion, and the remaining bulge is formed.
Mostly the microphone to which the microphone is attached
Phone mounting part, and the inner hole and the
Sound absorbing material is filled between the microphone mounting part
A sound-absorbing material filling is formed, this filling being adjacent on one side
Larger than the inner diameter of the inner hole that is in contact, and adjacent on the other side
Smaller than the inner diameter of the microphone mounting part in contact
Is a with which the probe, the probe microphone comprising.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18664494A JP3324876B2 (en) | 1994-07-15 | 1994-07-15 | Probe microphone |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18664494A JP3324876B2 (en) | 1994-07-15 | 1994-07-15 | Probe microphone |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0833084A JPH0833084A (en) | 1996-02-02 |
| JP3324876B2 true JP3324876B2 (en) | 2002-09-17 |
Family
ID=16192203
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP18664494A Expired - Fee Related JP3324876B2 (en) | 1994-07-15 | 1994-07-15 | Probe microphone |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3324876B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ATE320160T1 (en) * | 2000-05-25 | 2006-03-15 | Gn Netcom As | ßAUCUSTIC TRANSMISSION CONNECTION, HEADPHONES WITH ACOUSTIC TRANSMISSION CONNECTION AND USES OF THE ACOUSTIC TRANSMISSION CONNECTIONß |
| JP4783873B2 (en) * | 2000-08-11 | 2011-09-28 | 有限会社 サイプラス | Environmental state measuring apparatus and method |
| JP4904848B2 (en) * | 2006-02-24 | 2012-03-28 | いすゞ自動車株式会社 | Probe microphone mounting structure |
| JP6540498B2 (en) * | 2015-12-21 | 2019-07-10 | 富士通株式会社 | Electronics |
-
1994
- 1994-07-15 JP JP18664494A patent/JP3324876B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0833084A (en) | 1996-02-02 |
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