JPS59190795A - Piezoelectric type low frequency transducer - Google Patents
Piezoelectric type low frequency transducerInfo
- Publication number
- JPS59190795A JPS59190795A JP6583583A JP6583583A JPS59190795A JP S59190795 A JPS59190795 A JP S59190795A JP 6583583 A JP6583583 A JP 6583583A JP 6583583 A JP6583583 A JP 6583583A JP S59190795 A JPS59190795 A JP S59190795A
- Authority
- JP
- Japan
- Prior art keywords
- piston
- transducer
- low frequency
- lever
- piezoelectric
- 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.)
- Granted
Links
- 238000006073 displacement reaction Methods 0.000 claims abstract description 10
- 239000000919 ceramic Substances 0.000 claims description 16
- 238000010586 diagram Methods 0.000 description 3
- 230000005855 radiation Effects 0.000 description 3
- 230000003321 amplification Effects 0.000 description 2
- 238000003199 nucleic acid amplification method Methods 0.000 description 2
- 238000005452 bending Methods 0.000 description 1
- 210000000941 bile Anatomy 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000005520 electrodynamics Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
- B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
- B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
- B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
- B06B1/06—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction
Abstract
Description
【発明の詳細な説明】
本発明は数百１＋ｚ以下の低周波トランスジューサに関
するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to low frequency transducers of several hundred 1+z or less.
近年、音波による水中探査や水中伝搬の研究のみならず
超速距離トランスジーーサとして１ｏｏｎｚ〜数百Ｈｚ
（７）周波数範囲で１８０ｄＢ ｒｅ １μＰａ以
上の音圧レベルが得られる低周波音源が強く望まれてい
る。周知の如く、これらの低周波音源は遠距離音波伝搬
の観点から、１０００ｍ程度かそれ以上の海中に沈めて
使用する。In recent years, research has been conducted not only on underwater exploration and underwater propagation using sound waves, but also as an ultra-fast distance transformer with frequencies ranging from 1oonz to several hundred Hz.
(7) A low-frequency sound source that can obtain a sound pressure level of 180 dB re 1 μPa or higher in a frequency range is strongly desired. As is well known, from the viewpoint of long-distance sound wave propagation, these low-frequency sound sources are used by being submerged in the sea at a depth of about 1000 m or more.
低周波音源の駆動方式として、従来動電形あるいはバリ
アブルレラクタンス形が提案されているが、１０００ｍ
程度の深海で動作させるためには、リキッドフィルドも
しくは圧カバランス形トランスジューサ構成とさせるこ
とが必要不可欠でありこのため駆動力が小さすぎ必要な
音圧を得ることが極めて困難であるといった欠点がある
。Conventionally, electrodynamic type or variable reluctance type have been proposed as drive methods for low frequency sound sources, but
In order to operate at such depths, it is essential to have a liquid-filled or pressure-capacity transducer configuration, which has the disadvantage that the driving force is too small and it is extremely difficult to obtain the necessary sound pressure. .
一方、圧電形トランスジー−サは十分な駆動力が得られ
るが、１８０ｄＢ ｒｅ １μＰａ という音圧に見合
うだけの放射端面の速度を得ることが、従来困難であっ
た。On the other hand, although piezoelectric transducers can provide sufficient driving force, it has been difficult in the past to obtain a speed of the radiation end face that is commensurate with the sound pressure of 180 dB re 1 μPa.
本発明は深海でも安定に動作させるため、圧力バランス
形のＨｅ Ｉｍｈｏ Ｉ ｔ ｚ共振器を用い、さらに
変位拡大機構を設け、従来の圧電形トランスジユーサの
放射端面の速度が小さいという欠点を解消し大きな音圧
を得ることができるピストン振動形低周波トランスジー
−サを実現させるためになされたものである。以下図面
について説明する。In order to operate stably even in the deep sea, the present invention uses a pressure-balanced He Imho I tz resonator and is further equipped with a displacement amplification mechanism, thereby solving the drawback of the low velocity of the radiation end face of conventional piezoelectric transducers. This was done in order to realize a piston vibration type low frequency transformer that can obtain a large sound pressure. The drawings will be explained below.
第１図は、従来のピストン振動タイプ低周波圧電形トラ
ンスジー−サの一例を示す。第１図に於て、１０は圧電
セラミック部分を示し、この部分はボルト締めランジュ
バン振動子で周知の如く隣接する円筒状圧電セラミック
振動子の分極方向が互いに逆向きで、機械的には縦続接
続、電気的には並列接続され、またボルトであらかじめ
機械的な圧縮応力のかけられた状態で使用される。FIG. 1 shows an example of a conventional piston vibration type low frequency piezoelectric transducer. In FIG. 1, numeral 10 indicates a piezoelectric ceramic part, and as is well known in bolted Langevin oscillators, adjacent cylindrical piezoelectric ceramic oscillators have opposite polarization directions and are mechanically connected in cascade. , electrically connected in parallel, and mechanically compressed with bolts before use.
１１は結合子％１２はピスト７４１体板、１３は）（６
１ｍｈ０１ｉｚ共振器のエンクロージャ一部分、１４は
Ｈｅ Ｉｍｈｏ ｌ ｔ ｚ共振器の空胴部分を示す。11 is the connector% 12 is the piston 741 body plate, 13 is) (6
The enclosure part of the 1mh01iz resonator, 14 indicates the cavity part of the He Imho l t z resonator.
丈た、第１図Ｊこ示したトランスジー−サの電気−機械
振動系に関する等価回路表示を第２図に示す。FIG. 2 shows an equivalent circuit representation of the electro-mechanical vibration system of the transducer shown in FIG. 1.
第２図に於てＣｄは制動容量、人は力係数、Ｃｃは圧電
セラミック部分のコンプライアンス、Ｃｓ１は結合子の
コンプライアンス、ｍｘはピストン剛体板の質量、ｖｔ
、Ｆｘ はそれぞれピストン放射端面における速度、力
を示す。In Figure 2, Cd is the braking capacity, force coefficient is Cc, compliance of the piezoelectric ceramic part, Cs1 is compliance of the connector, mx is the mass of the piston rigid plate, vt
, Fx represent the velocity and force at the radial end surface of the piston, respectively.
第１図に示したトランスジューサの共振周波数ｆ□は、
増幅器に接続して駆動した場合、で与えられる。（１）
式より結合子のコンプライアンスＣ６、を増し、ピスト
ンの質量ｍ１を増すほど低周波化が図られることがわか
るｏしかしながら）Ｃｃｌ、ｍｘを増大させるほど十分
な音圧を得るためのピストン放射端面の速度ｖ１に対し
一、Ｖｘよりかなり大きな圧電セラミック部分の振動速
度が必要である。The resonant frequency f□ of the transducer shown in Fig. 1 is
When connected to an amplifier and driven, it is given by. (1)
From the equation, it can be seen that the frequency can be lowered as the compliance of the connector C6 is increased and the mass m1 of the piston is increased. However, as Ccl and mx are increased, the speed of the piston radiation end surface to obtain sufficient sound pressure For v1, a vibration velocity of the piezoceramic part that is significantly greater than Vx is required.
即ち、低周波化を図るためにはピストン部分の振動速度
に対してかなり余裕をもって圧電セラミック部分の振動
速度を設定してやる必要があるが、圧電セラミック部分
の振動速度を上げるためには材料上からくる一定の限界
があり、従来のトランスジー−サではエネルギー効率が
悪くなることは明白である。In other words, in order to reduce the frequency, it is necessary to set the vibration speed of the piezoelectric ceramic part with a considerable margin relative to the vibration speed of the piston part, but in order to increase the vibration speed of the piezoelectric ceramic part, it is necessary to set the vibration speed of the piezoelectric ceramic part from the material. It is clear that there are certain limitations and that conventional transducers have poor energy efficiency.
本発明はこれらの欠点を除いた高効率の圧電形低周波ト
ランスジューサを提供することを目的とする。An object of the present invention is to provide a highly efficient piezoelectric low frequency transducer that eliminates these drawbacks.
すなわち本発明はへルムホルッの共振器を具備したピス
トン運動タイプ圧電形トランスジューサにおいてレバー
及びヒンジからなる変位拡大機構が付加されたことを特
徴とする圧電形低周波トランスジー−サである。That is, the present invention is a piezoelectric low-frequency transducer characterized in that a piston motion type piezoelectric transducer equipped with a Helmholt resonator is additionally provided with a displacement magnification mechanism consisting of a lever and a hinge.
本発明の低周波トランスジューサの一例を第３図に示す
。An example of the low frequency transducer of the present invention is shown in FIG.
第３図において、加は第１図と同様の圧電セラミック部
分、２１はヒンジ、２２はレバー、詔は結合子、２４は
ピストン剛体板、石はｉ（ｅｌｍｈｏｌｔｚ 共振器の
エンクロージャ一部、２ｂはＨｅ １ｍｈ ｏ １ ＠
ｚ 共振器の空胴部分を示し１圧電セラミック部分２
０の変位をてこの原理により拡大することを意図したも
のである。第３図のトランスジューサの動作Ｗ、埋ヲ詳
述するにあたり、主要部分の構成を第４図に示す。In FIG. 3, the addition is the same piezoelectric ceramic part as in FIG. 1, 21 is the hinge, 22 is the lever, 2 is the connector, 24 is the piston rigid plate, the stone is part of the enclosure of the elmholtz resonator, and 2b is the He 1mh o 1 @
z indicates the cavity part of the resonator 1 piezoelectric ceramic part 2
It is intended to expand the zero displacement using the lever principle. To explain in detail the operation W of the transducer shown in FIG. 3, the configuration of the main parts is shown in FIG. 4.
第４図において、’１ Ｈ’ｌ ＊ ’Ｉは第３図にお
けるヒンジ２１を各部分に分けて記述したものであり、
ＩＬｌ、ＩＬ、はレバー２２の各部の長さを示す。また
ＩＬ４は結合子路を示す。第４図の動作特性を詳述する
ために、第４図の等価回路表示を第５図に示す。In FIG. 4, '1 H'l * 'I is a description of the hinge 21 in FIG. 3 divided into each part,
ILl and IL indicate the length of each part of the lever 22. Further, IL4 indicates a connector path. In order to explain the operating characteristics of FIG. 4 in detail, an equivalent circuit representation of FIG. 4 is shown in FIG.
第５図において、ｃｄは制動容量、Ａは力係数、ｃｏは
圧電セラミック部分のコンプライアンス、ｍ３は圧電セ
ラミック部分の等価質量、ＣＬ８．Ｃも。In FIG. 5, cd is the braking capacity, A is the force coefficient, co is the compliance of the piezoelectric ceramic part, m3 is the equivalent mass of the piezoelectric ceramic part, CL8. C too.
ＣＪ、はそれぞれヒンジＪ１．！、、Ｊ、のたてコンプ
ライアンス、ＣＢはヒンジＪ、から固定部分をみたコン
プライアンス、ＣはヒンジＪＬヨ、ｂ８
’ｓ間（Ｄレバーの撓みコンプライアンス、ＩＬはレバ
ーの慣性モーメン”Ｃｂｚはヒンジ’ １ ｐ ＧｅＪ
Ｌｓ及びセラミック部分からなる複合撓みコンプライア
ンス、ＣＬｂ＊はレバーＣＩＬ、−ξ、）部の撓みコン
プライアンス、ＣＪｔ４は結合子１４のたてフンプライ
アンス、ｒｎｘはピストン剛体板別の質量である〇
第５図からｌ ｘ、、／ ｌ ｒ、、よりｍ奪及び工、
はピストン板冴の質量ｍ１十分小さく設計することがで
き、トランスジューサの特性に関してほとんど無視して
考えられる。またＣｂｌはＣ０と比べてその影響は無視
できる。CJ, respectively, are hinges J1. ! , J, vertical compliance, CB is hinge J, compliance seen from the fixed part, C is hinge JL yo, b8's (D lever deflection compliance, IL is lever inertia moment, Cbz is hinge' 1 p GeJ
The composite deflection compliance consisting of Ls and the ceramic part, CLb* is the deflection compliance of the lever CIL, -ξ,) part, CJt4 is the vertical hinge compliance of the connector 14, and rnx is the mass of each piston rigid plate 〇Figure 5 From l x, , / l r, , from
The mass m1 of the piston plate can be designed to be sufficiently small, and the characteristics of the transducer can be almost ignored. Moreover, the influence of Cbl can be ignored compared to C0.
トランスジ、−サの低周波化に関して有効に働くコンプ
ライアンスは、回路に並列に配置されているコンプライ
アンスＣＪ、 、 Ｃｎ 、 ＣＪ、 、 ＣＪ、 、
ＣＩ、 ｂｘ。The compliance that is effective in lowering the frequency of the transformer is the compliance CJ, , Cn, CJ, , CJ, , which is placed in parallel in the circuit.
CI, bx.
ＣＬｔｌｙ ”ａであり、これらが低周波化に向けて協
力し合うわけである。またセラミック端面の速度はピス
トン端面では約１１６．／ＩＬ、倍に拡大されるわけで
ある。CLtly''a, and these work together to lower the frequency.Furthermore, the velocity of the ceramic end face is approximately 116./IL at the piston end face, which is doubled.
即ち、本発明の変位拡大機構とＨｅ１ｍｈｏｌｔｚ共振
器を用いたトランスジユーサでは、低周波化と同時にピ
ストン鉢体板において十分な振動変位がとれるわけであ
り、深海においてハイパワーかつ小形の低周波音源が実
現できるわけである。In other words, the transducer using the displacement amplification mechanism and the He1mholtz resonator of the present invention can achieve sufficient vibration displacement in the piston bowl body plate at the same time as lowering the frequency, and can be used as a high-power and small-sized low-frequency sound source in the deep sea. can be realized.
次に本発明の低周波音源の一実施例として、第３図の構
造を有するトランスジー−サについてのべる。ｌ（ｅ１
ｍｈｏｌｔｚ共振器δは２５０ Ｈｚに共振周波数があ
り、円筒形である。Next, as an embodiment of the low frequency sound source of the present invention, a transducer having the structure shown in FIG. 3 will be described. l(e1
The mholtz resonator δ has a resonant frequency at 250 Hz and is cylindrical.
ピストン剛体板Ｕは円形をしており、Ｈｅ１ｍｈｏｌｔ
ｚ共振器にわずかな間隙をもって内側に位置している。The piston rigid plate U is circular and has a He1mholt
It is located inside the z resonator with a slight gap.
駆動用圧電セラミック部は３ケ所あり、１２０ずつ隔た
っており、ピストン円板消の撓み節点に結合子囚を当接
している。また機械振動系に対する共振周波数は３００
Ｈｚ付近に設定されている。There are three driving piezoelectric ceramic parts, spaced apart by 120 mm, and the coupling element is brought into contact with the bending node of the piston disk. In addition, the resonance frequency for the mechanical vibration system is 300
It is set around Hz.
このトランスジューサのピストン板スからｉｒｎ離れた
ところの最大音圧を測定したところ第６図の実線の特性
を得た。一方、従来の第１図の構造を有する低周波音源
の同様の最大音圧特性は点線の特性となった。When the maximum sound pressure of this transducer was measured at a distance irn from the piston plate, the characteristics shown by the solid line in FIG. 6 were obtained. On the other hand, the similar maximum sound pressure characteristic of the conventional low-frequency sound source having the structure shown in FIG. 1 is the characteristic shown by the dotted line.
尚、いずれの音源も最大長は１ｒｎ未満であり、入力パ
ワーも同一である。従って、本発明に従うと低周波でハ
イパワーのトランスジー−サが実現できる。Note that the maximum length of both sound sources is less than 1 rn, and the input power is also the same. Therefore, according to the present invention, a low frequency, high power transformer can be realized.
第１図は従来のピストン振動低周波圧電形トランスジ−
サの構造図、第２図は第１図に示したトランスジー−サ
の電気機械振動系に関する等価回路図、第３図は本発明
の低周波圧電形トランスジー−サの構造図、第４図は第
３図のトランスジー−サの主要部分を示す図〜第５図は
第４図のトランスジ−サの等価回路図、第６図はトラン
スジー−サの最大音圧特性図である。
図において、１０．２０は圧電セラミック部分、１１゜
詔は結合子、１２．２４はピストン剛体板、１３．２５
はＨｅ１ｍｈｏｌｔｚ共振器エンクロージャー、１４，
２６はＨｅ１ｍｈｏｌｔｚ共振器空胴部分、２１はヒン
ジ、２２はレバー、Ｊ−１，も、ＪＩ−諺はヒンジ、Ｊ
Ｌ４は結合子、ｃｄは制動容量、Ａは力係数、ＣＣ，”
Ｓｔ 、 Ｃ４−ＣＪ＊、 Ｃ４，ＣＢ、 ＣＬｂｔ
、 Ｃｂｘ、 ＣＬｂｔ 、 Ｃ４ａはコンプライアン
ス、■□ はレバーの慣性モーメント、ｍｌはピストン
剛体板の質量、ｍｆｆ１は圧電セラミック部分の等価質
量、Ｖｘは振動速度、Ｆｌは力を示す。
オ １ 図
／ｊ １０ ／／
オ ？ 層
オ ３ 閃
ｚ５ ｚｔｉ ｉｔ ２２
７５ 胆
！１，４□：１Figure 1 shows a conventional piston vibration low frequency piezoelectric transformer.
2 is an equivalent circuit diagram of the electromechanical vibration system of the transducer shown in FIG. 1. FIG. 3 is a structural diagram of the low frequency piezoelectric transducer of the present invention. 3 shows the main parts of the transformer shown in FIG. 3, FIG. 5 shows an equivalent circuit diagram of the transformer shown in FIG. 4, and FIG. 6 shows the maximum sound pressure characteristics of the transformer. In the figure, 10.20 is the piezoelectric ceramic part, 11° is the connector, 12.24 is the piston rigid plate, and 13.25
is a He1mholtz resonator enclosure, 14,
26 is the He1mholtz resonator cavity, 21 is the hinge, 22 is the lever, J-1, also, JI-proverb is the hinge, J
L4 is the connector, cd is the braking capacity, A is the force coefficient, CC,"
St, C4-CJ*, C4,CB, CLbt
, Cbx, CLbt, and C4a are compliance, ■□ is the moment of inertia of the lever, ml is the mass of the piston rigid plate, mff1 is the equivalent mass of the piezoelectric ceramic part, Vx is the vibration velocity, and Fl is the force. O 1 Figure/j 10 // O? Layer o 3 flash z5 zti it 22 75 bile! 1,4□:1
Claims (2)
動タイプ圧電形トランスジューサにおいて、レバー及び
ヒンジからなる変位拡大機構が付加されたことを特徴と
する圧電形低周波トランスジューサ。(1) A piezoelectric low-frequency transducer characterized in that, in a piston vibration type piezoelectric transducer equipped with a Helmholtz resonator, a displacement magnification mechanism consisting of a lever and a hinge is added.
バーが２つのヒンジと接続しており、該２つのヒンジの
うち一方の他端は固定されており、他方の他端は圧電セ
ラミックと接続し、さらに前記レバーは結合子を介して
ピストン剛体板と接続している構造である特許請求の範
囲第１項記載の圧電形低周波トランスジー−サ。(2) In the displacement magnification mechanism consisting of a lever and a hinge, the lever is connected to two hinges, the other end of one of the two hinges is fixed, and the other end is connected to a piezoelectric ceramic, 2. The piezoelectric low frequency transducer according to claim 1, wherein said lever is connected to a piston rigid plate via a connector.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6583583A JPS59190795A (en) | 1983-04-14 | 1983-04-14 | Piezoelectric type low frequency transducer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6583583A JPS59190795A (en) | 1983-04-14 | 1983-04-14 | Piezoelectric type low frequency transducer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59190795A true JPS59190795A (en) | 1984-10-29 |
| JPH0448036B2 JPH0448036B2 (en) | 1992-08-05 |
Family
ID=13298465
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6583583A Granted JPS59190795A (en) | 1983-04-14 | 1983-04-14 | Piezoelectric type low frequency transducer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59190795A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6310697U (en) * | 1986-07-08 | 1988-01-23 | ||
| JPS6310699U (en) * | 1986-07-08 | 1988-01-23 | ||
| JPS6310698U (en) * | 1986-07-08 | 1988-01-23 | ||
| JPS63263443A (en) * | 1987-04-22 | 1988-10-31 | Ngk Spark Plug Co Ltd | Repetitive fatigue testing device |
-
1983
- 1983-04-14 JP JP6583583A patent/JPS59190795A/en active Granted
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6310697U (en) * | 1986-07-08 | 1988-01-23 | ||
| JPS6310699U (en) * | 1986-07-08 | 1988-01-23 | ||
| JPS6310698U (en) * | 1986-07-08 | 1988-01-23 | ||
| JPH0453116Y2 (en) * | 1986-07-08 | 1992-12-14 | ||
| JPH0510480Y2 (en) * | 1986-07-08 | 1993-03-15 | ||
| JPS63263443A (en) * | 1987-04-22 | 1988-10-31 | Ngk Spark Plug Co Ltd | Repetitive fatigue testing device |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0448036B2 (en) | 1992-08-05 |
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