JPS60120699A - Piezo-electric type electrical sound converter - Google Patents
Piezo-electric type electrical sound converterInfo
- Publication number
- JPS60120699A JPS60120699A JP22873683A JP22873683A JPS60120699A JP S60120699 A JPS60120699 A JP S60120699A JP 22873683 A JP22873683 A JP 22873683A JP 22873683 A JP22873683 A JP 22873683A JP S60120699 A JPS60120699 A JP S60120699A
- Authority
- JP
- Japan
- Prior art keywords
- sound
- air chamber
- chamber plate
- acoustic
- resistant material
- 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
Links
- 239000000463 material Substances 0.000 claims abstract description 12
- 230000035699 permeability Effects 0.000 claims abstract description 12
- 239000002184 metal Substances 0.000 claims description 10
- 229910052751 metal Inorganic materials 0.000 claims description 10
- 239000000919 ceramic Substances 0.000 abstract description 9
- 239000002759 woven fabric Substances 0.000 abstract description 8
- 239000000853 adhesive Substances 0.000 abstract description 3
- 230000001070 adhesive effect Effects 0.000 abstract description 3
- 238000007599 discharging Methods 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- WABPQHHGFIMREM-UHFFFAOYSA-N lead(0) Chemical compound [Pb] WABPQHHGFIMREM-UHFFFAOYSA-N 0.000 description 2
- 239000004745 nonwoven fabric Substances 0.000 description 2
- 241001492658 Cyanea koolauensis Species 0.000 description 1
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 1
- 229910000805 Pig iron Inorganic materials 0.000 description 1
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 229920005749 polyurethane resin Polymers 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 102220253361 rs1553234832 Human genes 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000004332 silver Substances 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 239000004753 textile Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R17/00—Piezoelectric transducers; Electrostrictive transducers
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Obtaining Desirable Characteristics In Audible-Bandwidth Transducers (AREA)
- Piezo-Electric Transducers For Audible Bands (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は電話機やインターボッなどの、！１１ｉにセラ
ミック圧電体をトランスジュビ−リと［７て用い／、−
圧電形電気音響変換器に関するもの−（ある。[Detailed Description of the Invention] Industrial Application Field The present invention is applicable to telephones, intercoms, etc. 11i, ceramic piezoelectric body is used as a transducer.
Related to piezoelectric electroacoustic transducers (Yes.
従来例の構成とその問題点
圧電形電気音響変換器には従来からセラミック圧電体を
金属振動板に貼イτｌし〕ζ振動子が多く用いられてい
る。この振動子を用い−Ｃ電気ざ響変換器を設剖する」
場合、振動子の支持固定方法とともに、音響抵抗拐の抵
抗値をどのように設定するかは、重要なポイントになる
。Conventional Structure and Problems Conventionally, piezoelectric electroacoustic transducers often use ζ oscillators in which a ceramic piezoelectric material is pasted on a metal diaphragm. Using this vibrator, we will construct a -C electroacoustic transducer.
In this case, how to set the resistance value of the acoustic resistor is an important point as well as how to support and fix the vibrator.
第１図に従来の圧電形電気音響変換器を示す。FIG. 1 shows a conventional piezoelectric electroacoustic transducer.
１はセラミック圧電体で両面には銀か焼料である。1 is a ceramic piezoelectric body with silver calcining material on both sides.
２目金属振動板でセラミ、り圧電体１と接着剤によって
密着し、電気的にも接続されている。３はケースて音響
８洩孔７．入力端子９，１２を有する背気室板１４と一
体となっている。４は４８動板２と放音孔６を有する前
気室板５との間の空間を確保し、振動板２の周辺を固定
するリングである。The second metal diaphragm is in close contact with the ceramic piezoelectric body 1 with an adhesive and is also electrically connected. 3 is the case with acoustic 8 leak holes 7. It is integrated with a back air chamber plate 14 having input terminals 9 and 12. A ring 4 secures a space between the 48 moving plate 2 and the front air chamber plate 5 having the sound emitting holes 6, and fixes the periphery of the diaphragm 2.
人力☆Ｉ”１．１子９何、り−−ス３と絶縁体１０によ
り電気的に分ガ［され、リ−１・′線８によってセラミ
ック圧電体１の一方の電極と電気的に接続されている。Human power ☆I"1.1 The wire 9 is electrically separated by the wire 3 and the insulator 10, and electrically connected to one electrode of the ceramic piezoelectric body 1 by the wire 1/' wire 8. has been done.
他方の入力端子１２もリード線１１によって振動板２を
通じセラミック圧電体１の他方の電極と電気的に接続ｌ
〜である。１３は音響抵抗拐で、振動子の共振、背気室
の共鳴による出力音圧の大きな変動を抑制する役目を持
っている。The other input terminal 12 is also electrically connected to the other electrode of the ceramic piezoelectric body 1 through the diaphragm 2 by the lead wire 11.
It is ~. Reference numeral 13 denotes an acoustic resistance, which has the role of suppressing large fluctuations in the output sound pressure due to resonance of the vibrator and resonance of the back air chamber.
電話用発音体の場合、従来（は抵抗値を直接知る方θ（
かなかつたため、不織イ］Ｊのような多孔質材を数枚Ｉ
Ｆねるなどして、１１１圧周波数特１／１．を確認し２
て沃めてい／こが、特性の変動１＋か人きく出現性の良
いものがイ４）られなかったり、４．！１１４１をぞろ
えるため個々の変換器について音響抵抗を調整するエイ
ゲを入れるなどして特性を確保してい／ζ０発明の目的
本発明の目的は、電話機やインターホンなどの受話器に
ついて、前気室−振動子−背気室から成る自由度３の構
成とし、背気に；イ板に設けた音響漏洩孔を覆うように
設けた音響抵抗月によ−ｊて、γ♀圧周波数特１勺・を
平坦にし、出現性の良い圧？ｉｚ形電気音響変換器を提
供するものである。In the case of telephone sounding bodies, conventionally (the method of directly knowing the resistance value θ(
Due to the short time, several pieces of porous material such as non-woven material
111 pressure frequency characteristic 1/1. Check 2
However, if the characteristics change 1+ or the appearance is good, it may not be possible. ! In order to match the 1141, the characteristics are secured by including an Eige to adjust the acoustic resistance of each transducer. It has a configuration with 3 degrees of freedom consisting of a vibrator and a back air chamber, and the back air has a γ♀ pressure frequency characteristic of 1. Is there a good pressure to flatten it and make it appear? An iz-type electroacoustic transducer is provided.
発明の構成
不発１ｎＪＩｒ−１１′Ｊ−重刑電気音響変換ｚ：）、
Ｑ、ｌＪニ電１！ｉｒｉ 機ヤインターポンなどの受話
器？〔，１ζンミノク圧電体を金属振動板に貼伺して振
動ｒと４： ｉ−、、−その振動子の周辺を固定するケ
ースと背気室板とから成り、振動子と放音孔を准するケ
ースとの間を前気室とし、振動子と音響漏洩孔と入力端
子をイ］−する背気室板との間を背気室としだ前気室−
振動子−背気室の自由度３の構成とし、背気室板の音響
漏洩孔には通気度が１６〜４０ｃｃ／Ｃ＃ｊ７ｅＣであ
る織布がら成る音響抵抗月を設けた構造になっている。Invention configuration misfire 1nJIr-11'J-heavy electroacoustic conversion z:),
Q, lJ Niden 1! iri A telephone receiver such as a machine intercom? [,1ζNminoku piezoelectric material is pasted on a metal diaphragm to produce vibrations r and 4: i-, , - It consists of a case that fixes the area around the vibrator and a back air chamber plate, and the vibrator and sound emission hole are fixed. The front air chamber is between the transducer, the acoustic leak hole, and the input terminal, and the back air chamber is between the transducer, the acoustic leak hole, and the input terminal.
The structure has three degrees of freedom between the vibrator and the back air chamber, and the acoustic leak hole in the back air chamber plate is provided with an acoustic resistance moon made of woven fabric with an air permeability of 16 to 40 cc/C#j7eC. There is.
実施例の説明
第２図に本発明の音響抵抗拐を装着した圧電形？ｌｉ気
７に響変換器の断面図を示す。DESCRIPTION OF THE EMBODIMENTS Fig. 2 shows a piezoelectric type equipped with the acoustic resistor of the present invention. Figure 7 shows a cross-sectional view of the acoustic transducer.
２１はケースで、放音孔２２が複数個設けである。ケー
ス２１は金属製でドーム状をなし金属振動板２３との間
に前気室３２を形成している。この金属振動板２３とケ
ース２１は電気的に接続さ力ている。セラミック圧電体
２４と金属振動板２３シ１．接着剤により密着し、電気
的にも導通を得ており、この両者で振動子３１を構成し
ている。金属振動板２３の周辺はケース２１の股部分２
１ａと、背気室板２５の周辺の凸部２５ａとによって固
定されている。背気室板２５に一一音響漏洩孔２６と入
力端子２７が設けてあり、音響漏洩孔２６には音響抵抗
；１４’ ２８が貼付けてあり端子板２９によって抑え
られている。これらは、ケース２１内に収納されてから
り″−ス２１の一部を曲げ加にづることによッテ固定さ
ｒＬ でイル（、−４だ、Ｂ４ ］ｉ１７ ”（−３１
ト背気室板２５との間に背気室３３が形成されている。Reference numeral 21 denotes a case, which is provided with a plurality of sound emitting holes 22. The case 21 is made of metal and has a dome shape, and forms a front air chamber 32 between the case 21 and the metal diaphragm 23. The metal diaphragm 23 and the case 21 are electrically connected. Ceramic piezoelectric body 24 and metal diaphragm 23 1. They are closely attached with adhesive and electrically conductive, and the two constitute the vibrator 31. The area around the metal diaphragm 23 is the crotch part 2 of the case 21
1a and a protrusion 25a around the back air chamber plate 25. A back air chamber plate 25 is provided with an acoustic leak hole 26 and an input terminal 27, and an acoustic resistor 14' 28 is attached to the acoustic leak hole 26 and suppressed by a terminal plate 29. These are housed in the case 21 and fixed by bending a part of the base 21.
A back air chamber 33 is formed between the back air chamber plate 25 and the back air chamber plate 25.
セラミノ圧電体２４の他方の電極志人力９１八；子２７
とはリード線３０によ−〕−〔電気的に接続されている
。The other electrode of the ceramino piezoelectric body 24 918; child 27
and are electrically connected by lead wires 30.
本発明は以上の構成の中で音響抵抗の値を規定するもの
である。本発明しｊ：、音響抵抗の値は音響抵抗利２８
の通気度に強い相関が認めら才することがら音響抵抗旧
２８として通気度の面内の変動１＋が小さい織布を選び
、−ぞのｆＩＩＩＩ゛が１５〜４０ＣＣ／’ｃ７１ブ／
ｓｅｃにあれば、組立後のｑＪｆＪ整など余分な−［）
Ｈ’６必要とせず１す現性の良い圧電形電気音響変（力
器をｆ′Ｉることかできる。通気１ｕｌｌ Ｊ Ｉ Ｓ
規格Ｌ１０９６一般織物試験法６．２７．１Ａ法による
値である３、」メ下実施例に従って説明する。The present invention defines the value of acoustic resistance in the above configuration. According to the present invention, the value of the acoustic resistance is the acoustic resistance gain 28
Since there is a strong correlation between the air permeability and the acoustic resistance, a woven fabric with a small in-plane variation in air permeability of 1+ is selected as the acoustic resistance old 28.
If it is in sec, there is an extra -[) such as qJfJ adjustment after assembly.
A piezoelectric type electroacoustic transformer with good practicality without the need for H'6.
The value is 3 according to the standard L1096 general textile test method 6.27.1A method.
実施例１
第２図に示した構造で、背気室３３の容積０．２７ｃ
ｃ 、％ｉ−響凋洩孔２６の直径３ ｍ１ｎ、、、深さ
１．５ｍｍとして通気度が１５ ｃｃ１０ｊ／、”ｌＸ
： 、 ２５ ｃ ｃ ／ｒ：ｎｒ／Ａ＋ｒ 、 ４０
ｃ ｃ／Ｃｎ１Ａ部の織布を音響抵抗旧２８として用
いた。この織布は表面にポリウレタン樹脂をコーティン
グし通気度を小さくしだ。この結果得られた音圧周波数
特性を第３図に示す。第３図中ａ、ｂ、ｃはそれぞれ通
気度１ｃｓｃｃ／ａｄＡｙ、２６ｃｃ／ｃｎｉ／ｓｅｃ
、４゜ＣＣ／ＣＩＩ／ＳＬ′ＩＣの音響抵抗材２８を使
用した例を示している。Example 1 With the structure shown in FIG. 2, the volume of the back air chamber 33 is 0.27 c.
c, %i - The diameter of the sound leakage hole 26 is 3 m1n,..., the air permeability is 15 cc10j/,"lX as the depth is 1.5 mm
: , 25 c c /r:nr/A+r , 40
The woven fabric of c c/Cn1A section was used as acoustic resistance old 28. The surface of this woven fabric is coated with polyurethane resin to reduce air permeability. The sound pressure frequency characteristics obtained as a result are shown in FIG. In Figure 3, a, b, and c have air permeability of 1 cscc/adAy and 26 cc/cni/sec, respectively.
, 4° CC/CII/SL'IC acoustic resistance material 28 is used.
実施例２
実施例に示した構造で、通気度が約２５ ｃｃ／Ｃｒｒ
：Ａ（ＩＣの織布の中の任意の場所から１０個音響抵１
＞’Ｃ利を取抄出し変喚器を組立て、音圧周波数特性の
変動Ｉ＋］を調べた。その結果を第４図に示す。Example 2 The structure shown in Example has an air permeability of approximately 25 cc/Crr.
: A (10 acoustic resistors placed anywhere inside the IC fabric)
>'C interest was extracted, a converter was assembled, and the variation in sound pressure frequency characteristics (I+) was investigated. The results are shown in FIG.
比中交例
実施例２に示したのと同様の方法で通気度が約２５ ｃ
ｃ／ｃ〃ｉ／Ｓ銑の不織布を音響抵抗材として用い、
音圧周波数特性を測定した。結果を第５図に示す。The air permeability was approximately 25 c using the same method as shown in Example 2.
Using c/c〃/S pig iron non-woven fabric as an acoustic resistance material,
The sound pressure frequency characteristics were measured. The results are shown in Figure 5.
発明の効果
本発明のような構成の音響抵抗材を使用することにより
音圧周波数特性が平坦で、かつ再現性のよく、工業的に
意義のある圧電形電気音響変換器が実現できる。第３図
に示し／こように、織布の通気度が１５−４０ ｃ ｃ
／ｃｎＩ７１ｓｃｃであるイ［Ｉをｊ’９響抵抗利と
して使用することにまり音圧周波載持１／日；［下用な
ものか実現できる。音響抵抗）ｌＡとして織布を用いる
ことに」ニリ音Ｈ−周波数特性の変動ＩＩ］の少々い再
現１（＋の良い圧電形電気音響変換器が実現できるもの
である。Effects of the Invention By using an acoustic resistance material configured as in the present invention, it is possible to realize a piezoelectric electroacoustic transducer with flat sound pressure frequency characteristics and good reproducibility, which is industrially significant. As shown in Figure 3, the air permeability of the woven fabric is 15-40 c c
/cnI71scc I [I can be realized by using the sound pressure frequency for 1/day by using it as a j'9 sound resistance. By using a woven fabric as the acoustic resistance (1A), a piezoelectric electroacoustic transducer with good resistance (+) can be realized.
第１図は従来の圧電形電気音響変換器の断面図、第２図
は本発明による音響抵抗月を装殖した圧電形電気１′！
ｌ響変換器の一実施例を；１：、ず断１ｉ’ｊ図、第３
図は本発明による音響抵抗利を装着シッフξ時の音１１
周波数特性図、第４図回一本発明による〕）ｕ気度約２
らＣＣ／ｃｎｉ／Ｆ１２Ｃの織布を使用し７’ｊ ｔｌ
、’ｌの１・′？圧周彼数４１、〒ＰＩの変動＋１−］
を示す特性図、第５図は］、比１に例に示した不織布を
使用した時の音圧周波数！１１゛・１／１の変動Ｉ］Ｊ
を示した特性図である。
２１・ ケース、２２・・放音孔、２３ ・・金属振動
板、２４・ セラミック圧電体、２６・背気室板、２６
・・音響漏洩孔、２７・・・入力端子、２８ ・音響抵
抗材、２９・・端子板、３０・・・リード線、３１・・
−・振動子、３２・・ 前気室、３３−−背気室。
代理人の氏名 弁理士 中 尾 敏 男 はが１名第１
図
第２図
第３図
囚 破波（／ｈ＋FIG. 1 is a sectional view of a conventional piezoelectric electroacoustic transducer, and FIG. 2 is a piezoelectric electroacoustic transducer according to the present invention equipped with an acoustic resistance transducer 1'!
An example of an acoustic transducer; 1:, section 1i'j diagram, third
The figure shows the sound 11 when the acoustic resistance gain according to the present invention is attached to Schiff ξ.
Frequency characteristic diagram, Fig. 4 according to the present invention]) u air temperature approx. 2
Using CC/cni/F12C woven fabric, 7'j tl
,'l'1・'? Pressure circumference number 41, PI fluctuation +1-]
The characteristic diagram, Figure 5, shows the sound pressure frequency when using the nonwoven fabric shown in the example in Ratio 1! 11゛・1/1 fluctuation I]J
FIG. 21. Case, 22. Sound emission hole, 23. Metal diaphragm, 24. Ceramic piezoelectric body, 26. Back air chamber plate, 26
・Acoustic leak hole, 27 ・Input terminal, 28 ・Acoustic resistance material, 29 ・Terminal board, 30 ・Lead wire, 31 ・
- - Vibrator, 32... Front air chamber, 33 - Back air chamber. Name of agent: Patent attorney Toshio Nakao (1st person)
Figure 2 Figure 3 Prisoner Haha (/h+
Claims (1)
こ振動子の周辺を固定するケースと背気室板とから成り
、上記振動子−と放音孔を有するり一−−スとの間に前
気室を設け、振動子と音響／７１１ｊ洩孔と人力☆：！
ｔｉ ’ｆ” ＣＣイ］する背気室板との間に背気室を
設け、−１，記ｊ？響１７１ｉｉ洩孔に通気度が１５〜
４０ ｃｃ／ｌ：ｎｉ／５ＣＩＣの織イ１ｊイｃ音響抵
抗月として設けて成る圧電形電気ｉ″ｌ響変ｉ１７！器
。[Claims] A lamino piezoelectric material I [attached to a metal diaphragm (t L /
This consists of a case that fixes the periphery of the vibrator and a back air chamber plate, and a front air chamber is provided between the vibrator and the base having sound emission holes, and Hole and human power ☆:!
A back air chamber is provided between the back air chamber plate and the leak hole has an air permeability of 15 to 15.
40 cc/l: ni/5 CIC piezoelectric type electric i''l sound change i17! device provided as a woven I1j Ic acoustic resistance month.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22873683A JPS60120699A (en) | 1983-12-02 | 1983-12-02 | Piezo-electric type electrical sound converter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22873683A JPS60120699A (en) | 1983-12-02 | 1983-12-02 | Piezo-electric type electrical sound converter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS60120699A true JPS60120699A (en) | 1985-06-28 |
Family
ID=16881008
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22873683A Pending JPS60120699A (en) | 1983-12-02 | 1983-12-02 | Piezo-electric type electrical sound converter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60120699A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6390395U (en) * | 1986-12-02 | 1988-06-11 | ||
| US8141675B2 (en) * | 2009-06-26 | 2012-03-27 | AAC Acoustic Technologies (Shenzhen) Co. Ltd. | Micro-speaker |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5656098A (en) * | 1979-10-11 | 1981-05-16 | Matsushita Electric Ind Co Ltd | Microphone |
-
1983
- 1983-12-02 JP JP22873683A patent/JPS60120699A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5656098A (en) * | 1979-10-11 | 1981-05-16 | Matsushita Electric Ind Co Ltd | Microphone |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6390395U (en) * | 1986-12-02 | 1988-06-11 | ||
| JPH0526875Y2 (en) * | 1986-12-02 | 1993-07-07 | ||
| US8141675B2 (en) * | 2009-06-26 | 2012-03-27 | AAC Acoustic Technologies (Shenzhen) Co. Ltd. | Micro-speaker |
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