JPS62247700A - Piezoelectric speaker - Google Patents
Piezoelectric speakerInfo
- Publication number
- JPS62247700A JPS62247700A JP8919886A JP8919886A JPS62247700A JP S62247700 A JPS62247700 A JP S62247700A JP 8919886 A JP8919886 A JP 8919886A JP 8919886 A JP8919886 A JP 8919886A JP S62247700 A JPS62247700 A JP S62247700A
- Authority
- JP
- Japan
- Prior art keywords
- piezoelectric
- composite piezoelectric
- ring
- electrodes
- resin
- 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
- 239000002131 composite material Substances 0.000 claims abstract description 24
- 239000000463 material Substances 0.000 claims abstract description 23
- 239000000126 substance Substances 0.000 claims abstract description 6
- 239000002184 metal Substances 0.000 claims description 6
- 229910052751 metal Inorganic materials 0.000 claims description 6
- 239000011368 organic material Substances 0.000 claims description 6
- 239000010408 film Substances 0.000 claims 1
- 230000001681 protective effect Effects 0.000 claims 1
- 239000010409 thin film Substances 0.000 claims 1
- 239000000919 ceramic Substances 0.000 abstract description 11
- 239000003822 epoxy resin Substances 0.000 abstract description 6
- 229920000647 polyepoxide Polymers 0.000 abstract description 6
- 239000000853 adhesive Substances 0.000 abstract description 5
- 230000001070 adhesive effect Effects 0.000 abstract description 5
- WABPQHHGFIMREM-UHFFFAOYSA-N lead(0) Chemical compound [Pb] WABPQHHGFIMREM-UHFFFAOYSA-N 0.000 abstract description 4
- 238000000034 method Methods 0.000 abstract description 3
- 239000005416 organic matter Substances 0.000 abstract description 3
- 229920005989 resin Polymers 0.000 abstract description 3
- 239000011347 resin Substances 0.000 abstract description 3
- 229920002803 thermoplastic polyurethane Polymers 0.000 abstract description 3
- 239000011295 pitch Substances 0.000 abstract 1
- 230000000694 effects Effects 0.000 description 4
- 239000003795 chemical substances by application Substances 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 229920001971 elastomer Polymers 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- KXGFMDJXCMQABM-UHFFFAOYSA-N 2-methoxy-6-methylphenol Chemical compound [CH]OC1=CC=CC([CH])=C1O KXGFMDJXCMQABM-UHFFFAOYSA-N 0.000 description 1
- 239000007767 bonding agent Substances 0.000 description 1
- 239000000470 constituent 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
- 238000007606 doctor blade method Methods 0.000 description 1
- 239000007772 electrode material Substances 0.000 description 1
- 229910001651 emery Inorganic materials 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000004898 kneading Methods 0.000 description 1
- VJPLIHZPOJDHLB-UHFFFAOYSA-N lead titanium Chemical compound [Ti].[Pb] VJPLIHZPOJDHLB-UHFFFAOYSA-N 0.000 description 1
- 230000000873 masking effect Effects 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 229920001568 phenolic resin Polymers 0.000 description 1
- 239000005011 phenolic resin Substances 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
Landscapes
- 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、圧電効果を利用したスピーカーに関するもの
であり、特に圧電セラミックスを用いた圧電スピーカー
に係るものである。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a speaker that utilizes the piezoelectric effect, and particularly to a piezoelectric speaker that uses piezoelectric ceramics.
従来の技術
従来、一般にスピーカーは、永久磁石とボイスコイルに
より音声にあった電気信号を振動に変え、それを振動板
その他の手段を用いて拡大することにより、音声の再生
が行われるものである。しかしながら、音声の再生にお
いて、周波数の領域を十分にとらえる為には、各領域に
あったスピーカーを用意する必要があり、１個のスピー
カーでは補えない状況である。Conventional technology Conventionally, speakers generally reproduce sound by converting electrical signals corresponding to sound into vibrations using a permanent magnet and voice coil, and amplifying the vibrations using a diaphragm or other means. . However, in order to sufficiently capture frequency ranges in audio reproduction, it is necessary to prepare speakers suitable for each range, and this cannot be achieved with a single speaker.
また、マグネット・スピーカーは、音圧を高めるために
は大きくなり、また、重量的にも重いものどなる。Additionally, magnetic speakers need to be large in order to increase the sound pressure, and they are also heavy in weight.
近年、種々の商品は軽薄短小化に向かい、スピーカーも
この傾向にあり、極めて薄型かつ軽量の平板型スピーカ
ー等が求められている。かかる要求に答えるものとして
、例えば圧電効果を利用した発音体がある。In recent years, various products have become lighter, thinner, shorter, and smaller, and speakers are also following this trend, and extremely thin and lightweight flat-plate speakers and the like are in demand. To meet this demand, for example, there is a sounding body that utilizes the piezoelectric effect.
従来、圧電効果を利用した発音体としては、チタンジル
コン酸鉛（ＰＺＴ）系セラミックスの４根や右は圧電体
のシー１〜などが用いられている。Conventionally, as sounding bodies that utilize the piezoelectric effect, there have been used lead titanium zirconate (PZT) based ceramics 4 roots and piezoelectric materials C1~, etc.
圧電セラミックスの４根からなる発音体としては、これ
を一枚の金属板に貼り合わせたユニモルフ構造のものや
、金属板の両サイドに貼り合せたバイモルフ構造のもの
がある。また、近年、ドクターブレード法の活用により
、圧電セラミックスの薄肉化がなされつつありスピーカ
ーへの用途開発も行われつつある。Sounding bodies made of four piezoelectric ceramic roots include those with a unimorph structure, which are bonded to a single metal plate, and those with a bimorph structure, which are bonded to both sides of a metal plate. In addition, in recent years, piezoelectric ceramics have been made thinner by utilizing the doctor blade method, and their use in speakers is also being developed.
一方、有機圧電体のシートは容易に大面積のものが得ら
れ、フレキシブルで取り扱い上の問題はないが、大ぎな
音響パワーを得ることができない欠点がある。On the other hand, organic piezoelectric sheets can be easily obtained in large areas, are flexible, and pose no problems in handling, but have the disadvantage that they cannot obtain large acoustic power.
ざらには、有機物と圧電材粉末を混練した後、形を形成
する複合圧電体もある。There is also a composite piezoelectric material that is formed into a shape after kneading organic matter and piezoelectric material powder.
光用が解決しようとする問題点
しかしながら、従来より実用されている圧’ＭＡ ’ｔ
？ラミックス中板またはバイモルフ型は、比較的厚肉の
ものであり、弾性的性質に自由度がなく、しかもそれは
音饗的には硬い部類に入るため、高周波域には強いが、
低周波域には弱いものである。However, the problems that optical applications are trying to solve are
? The Lamix medium plate or bimorph type is relatively thick and has no flexibility in its elastic properties, and it falls into the hard category in terms of acoustics, so it is strong in high frequencies, but
It is weak in low frequency range.
これらを解決するために薄肉化も試みられてはいるが、
組立上のハンドリング、大面積化に問題が残る。Although attempts have been made to make the wall thinner to solve these problems,
Problems remain in handling during assembly and increasing the area.
また、有機圧電体は大変やわらかいために、入力が有機
圧電体内部に吸収され出力が小さくなる問題がある。Furthermore, since the organic piezoelectric material is very soft, there is a problem in that the input is absorbed inside the organic piezoelectric material and the output becomes small.
さらには、圧電セラミックス粉末と有機物を混ぜて作ら
れる複合圧電セラミックスは、当然のことながらセラミ
ックスバルクに比して特性が数段落ちる欠点がある、。Furthermore, composite piezoelectric ceramics made by mixing piezoelectric ceramic powder and organic matter naturally have the disadvantage that their properties are several steps lower than that of bulk ceramics.
本発明の目的は、大面積のものが比較的容易に得られ、
組立の過程ではフレキシブル性に富み、取り扱いに問題
なく、かつ大きな音響パワーを得ることができる圧電ス
ピーカーを促供するものである。The purpose of the present invention is to relatively easily obtain a large-area product;
The aim is to provide a piezoelectric speaker that is highly flexible during the assembly process, is easy to handle, and can generate a large amount of acoustic power.
問題点を解決するための手段
本発明は柱状圧電体を有機物で接合することにより、有
機物の持つ弾力性と圧電セラミックスバルクの持つ特性
（特に電気機械結合係数）を兼ね備えるようにした、複
合圧電体シートにＮ極をつ（）て用いることを特徴と１
６圧電スピーカーである。Means for Solving the Problems The present invention provides a composite piezoelectric material that combines the elasticity of the organic material and the properties (especially the electromechanical coupling coefficient) of the piezoelectric ceramic bulk by bonding columnar piezoelectric materials with an organic material. The feature is that the sheet is used with an N pole attached.
6 piezoelectric speakers.
このような構造の複合圧電体の概念は、たとえばマデリ
アル・リサーチ・プルディン（Ｍ ａｔｏｒｉａｌ
−Ｒｅ５ｅａｒｃｈ −ＢｕｌｌｅＮｎ ）誌第１３巻
、Ｐ５９９〜１）６０７（１９７８）に示されているが
、これをシート状にしてスピーカーに用いる着想はなか
った。The concept of a composite piezoelectric material with such a structure was developed, for example, by Material Research Pludin (Material Research Prudin).
-Re5earch-BulleNn), Vol. 13, P599-1) 607 (1978), but there was no idea to make it into a sheet and use it for a speaker.
本発明者らは、柱状圧電体の接合に用いる有機物として
、他構成材料〈たとえば電極材や柱状圧電体）との親和
性も良くかつ弾力性のある材料（例えばウレタン樹脂）
を用い、この複合圧電体の両面に電極をつけたのち、比
較的硬い有機物により、薄くかつ均一にオーバ−７１−
トをすることに」；す、フレキシブル性を有しながら当
蕾パワーのとれる発音体が得られることを見出した。The present inventors selected a material (for example, urethane resin) that has good affinity with other constituent materials (for example, electrode materials and columnar piezoelectric bodies) and has elasticity as an organic substance used for bonding columnar piezoelectric bodies.
After attaching electrodes to both sides of this composite piezoelectric material using
We have found that it is possible to obtain a sounding body that is flexible and has a lot of power.
本発明は、このような実験結果に基づきなされたちので
ある。The present invention was made based on such experimental results.
以下、本発明を実施例に基づいて詳しく説明する。Hereinafter, the present invention will be explained in detail based on examples.
実施例
実施例１
厚み方向に一様に分極された径１００ｍｎ＋、厚さ０．
５ＩＩＩＩＩｌのＰＺＴ系セラミックスを、平面度の出
ている加工用治具プレートに固定し、厚さ、０．２１ｍ
のブレードを用いて、溝深さ０．２ｉｌＩＩｌで、０．
１５１１１１１ビツヂで、網の目状に溝入れ加工した。Examples Example 1 Uniformly polarized in the thickness direction, diameter 100 mm+, thickness 0.
5IIII PZT ceramics was fixed to a processing jig plate with a flatness, and the thickness was 0.21 m.
With a groove depth of 0.2ilIIl, a groove depth of 0.2ilIIl was used.
Grooved into a mesh pattern using 1511111 bits.
加工により生じた溝にウレタン系樹脂を充填し、固化さ
せたのち、溝部分を加工用治具プレート而に当てて加工
し、網の目状が表われるまで切断除去した。このように
して（！Ｉられた複合圧電体シートを第１図に示す。図
において、１は柱状圧電体であり、２は弾性を有する有
機物である。この複合圧電体シート３を第２図に示ず如
く、金属あるいはフェノール樹脂のような固い材料から
なるリング４に軽く引張り応力がかかるようにして固着
する。本実施例ではスプリング・リング５を用いること
により複合圧電体に引張り応力がかかるようにして固定
した。After filling the grooves created by processing with urethane resin and solidifying it, the grooves were processed by applying them to a processing jig plate, and the resin was cut and removed until a mesh pattern appeared. The composite piezoelectric sheet 3 prepared in this manner is shown in FIG. As shown in the figure, the ring 4 made of a hard material such as metal or phenolic resin is fixed by applying a slight tensile stress.In this embodiment, a spring ring 5 is used to apply tensile stress to the composite piezoelectric material. That's how I fixed it.
しかる後に、複合圧電体シート３の両面に電極６及び６
′を形成Ｊる。この際、リング４が金属でできている場
合には、どららか−面につく電極６または６′が、リン
グ４及びスプリング・リング５を介して、複合圧電体シ
ート３の他の而に設【プられる゛電極６または６′ と
ショートしないように、たとえば、マスキングを行い、
第２図Ａ部のような被電極部分を設けるなどして電極６
，６′をつける。本実施例ではＣｒ−八〇をつけて打つ
Ｉこ 。After that, electrodes 6 and 6 are placed on both sides of the composite piezoelectric sheet 3.
′ is formed. At this time, if the ring 4 is made of metal, the electrode 6 or 6' attached to one side may be connected to other parts of the composite piezoelectric sheet 3 via the ring 4 and the spring ring 5. For example, masking is performed to prevent short circuit with the electrode 6 or 6' to be installed.
The electrode 6 can be
, 6' is added. In this example, Cr-80 is applied and struck.
次に、アース側及びプラス側に電極取出し口を設けるた
め、導電性＃８着剤７を電極面端部近傍の数個所に数ミ
リの大きざで高さ０．５ｎ＋ｍ程度塗り、この接湾剤７
が屹いた後、複合圧電体シート３の両面にエポキシ樹脂
８を薄くコートＪる。エポキシ樹脂８が固化後、導電性
接着剤７上部についたエポキシ樹脂８をエメリー紙等の
ｆσ１磨剤でこすり取り電極口を形成する。Next, in order to provide electrode outlets on the ground side and the positive side, apply conductive #8 adhesive 7 to several places near the end of the electrode surface in a width of several millimeters to a height of about 0.5n+m. Agent 7
After that, a thin layer of epoxy resin 8 is coated on both sides of the composite piezoelectric sheet 3. After the epoxy resin 8 is solidified, the epoxy resin 8 attached to the top of the conductive adhesive 7 is rubbed off with fσ1 polishing agent such as emery paper to form an electrode opening.
この取出し口にリード線９を取り付け、交流電圧を印加
したところ第５図に実線で示ザように広い周波数帯域に
亙り、効率よく音が発生した。When a lead wire 9 was attached to this outlet and an alternating current voltage was applied, sound was efficiently generated over a wide frequency band as shown by the solid line in FIG.
なお、第５図の点線で示したものは、比較のために作製
したＰＺＴｍ体板による再生周波数特性図である。The dotted line in FIG. 5 is a reproduction frequency characteristic diagram of a PZTm body plate prepared for comparison.
本発明によれば、音圧レベル８０ｄＢ以上にとると３０
０８２以上で安定になっていることがわかる。According to the present invention, when the sound pressure level is 80 dB or more, 30
It can be seen that it is stable at 082 or higher.
実施例２
実施例１で用いたものと同様の複合圧電体３をリング４
に固定する方法として、第３図に示すように、予め複合
圧電体３を、テンションをかけてプレー１−１０に貼り
つけ、ついで、第４図に示すように弾力性あるゴム系接
着剤１１（本例ではシリコンゴム系を用いた）により固
定し、ゴム系接着剤１１が固化後、プレート１０を複合
圧電体３より取り外し、アース側とプラス側のＭ極付、
リード線取出し口、オーバーコートを行い、リード線を
取り付け、交流電圧を印加したところ、実施例１で示し
た第５図よりも低周波側に周波数帯域がずれた１゜
実施例３
複合Ｆ［電体３のリング４への固定法として、実施例１
で試みたスプリング・リング５と、ゴム系接着剤１１を
併用して行ったところ、低周波側の出る音域となり、か
つ音響パワーも実施例２より＾いものが得られた。Example 2 A composite piezoelectric material 3 similar to that used in Example 1 was attached to a ring 4.
As shown in FIG. 3, as shown in FIG. 3, the composite piezoelectric material 3 is affixed to the plate 1-10 under tension in advance, and then, as shown in FIG. After the rubber adhesive 11 has solidified, the plate 10 is removed from the composite piezoelectric body 3, and the M poles on the ground side and positive side are attached.
When the lead wire outlet was overcoated, the lead wire was attached, and an AC voltage was applied, the frequency band shifted to the lower frequency side by 1° than that shown in FIG. 5 shown in Example 1.Example 3 Composite F[ As a method of fixing the electric body 3 to the ring 4, Example 1
When the spring ring 5 and the rubber adhesive 11 were used in combination, the sound range was on the low frequency side, and the acoustic power was also higher than in Example 2.
以上、実施例に基づき説明したが、柱状圧電体の大きさ
、柱状圧電体を整列接合させる有機物の厚さ調整により
周波数特性は調整可能である。また、複合圧電体の電極
付後、エポキシ樹脂等の比較的硬い樹脂のコートに際し
て、コート厚みによって周波数特性は調整可能である。Although the above description has been made based on the embodiments, the frequency characteristics can be adjusted by adjusting the size of the columnar piezoelectric bodies and the thickness of the organic material that aligns and joins the columnar piezoelectric bodies. Further, after attaching electrodes to the composite piezoelectric body, when coating with a relatively hard resin such as epoxy resin, the frequency characteristics can be adjusted by adjusting the coating thickness.
発明の効果
以、１−説明したように、柱状圧電体を有機物により、
整列接合されＩＣ構造の複合圧電体を用いてスピーカー
を作成する際、組立てに支障のないフレキシブル性を有
し、かつ、複合圧電体をリングに固定し、電極付後、オ
ーバーコートにより大きな音響パワーが取れるスピーカ
ーが得られる。さらに、整列接合される有機物の種類や
オーバーコートに使用する有機物の種類、厚みによって
も異なる音質を選ぶことができる。Since the effects of the invention are as follows: 1- As explained above, the columnar piezoelectric body is made of an organic substance,
When creating a speaker using a composite piezoelectric material that is aligned and bonded and has an IC structure, it has flexibility that does not hinder assembly, and the composite piezoelectric material is fixed to a ring, and after electrodes are attached, a large acoustic power is generated by overcoating. You can get a speaker that can take. Furthermore, different sound qualities can be selected depending on the type of organic material to be aligned and bonded, the type and thickness of the organic material used for the overcoat.
第１図は本発明に係わる複合圧電体シートの構造図、第
２図は実施例１を示す高面立体図、第３図及び第４図は
実施例２を示す図、第５図は実施例１による周波数に対
する音圧の測定値をブロツトシた図である。
１・・・柱状圧電体、２・・・有機物（接合剤）、３・
・・複合圧電体、４・・・リング、６．６′・・・電極
、８・・・エポキシ樹脂。
特許出願人 日立金属 株式会社
（ほか１名）
第１図
第３図FIG. 1 is a structural diagram of a composite piezoelectric sheet according to the present invention, FIG. 2 is a high-level three-dimensional view showing Example 1, FIGS. 3 and 4 are views showing Example 2, and FIG. 5 is an implementation example. FIG. 3 is a plot of measured values of sound pressure versus frequency according to Example 1; 1... Columnar piezoelectric body, 2... Organic substance (bonding agent), 3...
...Composite piezoelectric material, 4...Ring, 6.6'...Electrode, 8...Epoxy resin. Patent applicant: Hitachi Metals, Ltd. (and 1 other person) Figure 1 Figure 3
Claims (4)
に形成した複合圧電体の両面に電極を設けて構成された
ことを特徴とする圧電スピーカー。(1) A piezoelectric speaker characterized in that it is constructed by providing electrodes on both sides of a composite piezoelectric material formed in a sheet shape by bonding a plurality of columnar piezoelectric materials with an organic material.
ている特許請求の範囲第１項記載の圧電スピーカー。(2) The piezoelectric speaker according to claim 1, wherein an edge portion of the composite piezoelectric body is fixed to a frame.
特許請求の範囲第１項または第２項記載の圧電スピーカ
ー。(3) The piezoelectric speaker according to claim 1 or 2, wherein the electrode further has a protective film formed thereon.
音質調整用薄膜が形成された特許請求の範囲第１項乃至
第３項のいずれかに記載の圧電スピーカー。(4) The piezoelectric speaker according to any one of claims 1 to 3, wherein the electrode has a sound quality adjusting thin film made of an organic substance or metal formed thereon.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61089198A JP2624957B2 (en) | 1986-04-19 | 1986-04-19 | Piezoelectric speaker |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61089198A JP2624957B2 (en) | 1986-04-19 | 1986-04-19 | Piezoelectric speaker |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62247700A true JPS62247700A (en) | 1987-10-28 |
| JP2624957B2 JP2624957B2 (en) | 1997-06-25 |
Family
ID=13964013
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61089198A Expired - Lifetime JP2624957B2 (en) | 1986-04-19 | 1986-04-19 | Piezoelectric speaker |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2624957B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5684884A (en) * | 1994-05-31 | 1997-11-04 | Hitachi Metals, Ltd. | Piezoelectric loudspeaker and a method for manufacturing the same |
| JP2022106937A (en) * | 2019-03-29 | 2022-07-20 | エルジー ディスプレイ カンパニー リミテッド | Flexible vibration module and display device including the same |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6085700A (en) * | 1983-10-17 | 1985-05-15 | Hitachi Ltd | Ultrasonic probe and its manufacturing method |
-
1986
- 1986-04-19 JP JP61089198A patent/JP2624957B2/en not_active Expired - Lifetime
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6085700A (en) * | 1983-10-17 | 1985-05-15 | Hitachi Ltd | Ultrasonic probe and its manufacturing method |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5684884A (en) * | 1994-05-31 | 1997-11-04 | Hitachi Metals, Ltd. | Piezoelectric loudspeaker and a method for manufacturing the same |
| JP2022106937A (en) * | 2019-03-29 | 2022-07-20 | エルジー ディスプレイ カンパニー リミテッド | Flexible vibration module and display device including the same |
| US11930320B2 (en) | 2019-03-29 | 2024-03-12 | Lg Display Co., Ltd. | Flexible vibration module and display apparatus including the same |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2624957B2 (en) | 1997-06-25 |
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