JPH01243698A - Piezoelectric loudspeaker - Google Patents
Piezoelectric loudspeakerInfo
- Publication number
- JPH01243698A JPH01243698A JP7064588A JP7064588A JPH01243698A JP H01243698 A JPH01243698 A JP H01243698A JP 7064588 A JP7064588 A JP 7064588A JP 7064588 A JP7064588 A JP 7064588A JP H01243698 A JPH01243698 A JP H01243698A
- Authority
- JP
- Japan
- Prior art keywords
- piezoelectric
- shielding plate
- piezoelectric transducer
- peripheral wall
- rear end
- 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
- 230000002093 peripheral effect Effects 0.000 claims description 21
- 229920003002 synthetic resin Polymers 0.000 claims description 7
- 239000000057 synthetic resin Substances 0.000 claims description 7
- 230000002463 transducing effect Effects 0.000 abstract 2
- 238000005192 partition Methods 0.000 abstract 1
- 238000006243 chemical reaction Methods 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 239000000853 adhesive Substances 0.000 description 2
- 230000001070 adhesive effect Effects 0.000 description 2
- 239000000919 ceramic Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 230000005855 radiation Effects 0.000 description 2
- 229910001369 Brass Inorganic materials 0.000 description 1
- 239000010951 brass Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- NKZSPGSOXYXWQA-UHFFFAOYSA-N dioxido(oxo)titanium;lead(2+) Chemical compound [Pb+2].[O-][Ti]([O-])=O NKZSPGSOXYXWQA-UHFFFAOYSA-N 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000001465 metallisation Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 238000005476 soldering 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〕
この発明は、圧電素子を用いた圧電スピーカの容器構造
の改良に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in the container structure of a piezoelectric speaker using a piezoelectric element.
従来、圧電素子を以て電気信号を音響振動に変換する電
気音響変換器として圧電スピーカがある。2. Description of the Related Art Conventionally, piezoelectric speakers are known as electroacoustic transducers that convert electrical signals into acoustic vibrations using piezoelectric elements.
圧電スピーカは、圧電素子の電歪作用を利用して振動板
を直接駆動し、電気信号を音響振動に変換するため、薄
（、偏平で小型、低消費電力など、動電形スピーカに無
い優れた特徴を持っているが、圧電素子によって直接振
動板を駆動するという構造による音響特性からメロディ
アラームや玩具など限られた範囲で用いられて来た。Piezoelectric speakers utilize the electrostrictive effect of piezoelectric elements to directly drive a diaphragm and convert electrical signals into acoustic vibrations. However, it has been used in a limited range of applications such as melodic alarms and toys due to its acoustic characteristics due to the structure in which the diaphragm is directly driven by a piezoelectric element.
ところで、圧電素子をスピーカとして用いる場合、従来
は、装置の一部に簡易に固着するなどの方法が取られて
いるため、外装ケースが圧電素子とともに振動して不要
振動を誘発する共鳴体になるなど、忠実度に欠けるもの
であった。特に、圧電素子はその構造上の特徴から、そ
の設置空間の構造や、取付部材が音質などに密接な関係
を持っていることが知られており、音質など音響特性に
ついて改善が要請されている。By the way, when using a piezoelectric element as a speaker, conventional methods have been used such as simply fixing it to a part of the device, so the outer case vibrates together with the piezoelectric element and becomes a resonator that induces unnecessary vibrations. etc., lacked fidelity. In particular, due to the structural characteristics of piezoelectric elements, it is known that the structure of the installation space and mounting materials have a close relationship with sound quality, etc., and improvements in acoustic characteristics such as sound quality are required. .
そこで、この発明は、圧電素子などの板状電気音響変換
器の容器構造の工夫により、音質など、音響特性を改善
した圧電スピーカの提供を目的とする。Therefore, an object of the present invention is to provide a piezoelectric speaker with improved acoustic characteristics such as sound quality by devising the container structure of a plate-shaped electroacoustic transducer such as a piezoelectric element.
この発明の圧電スピーカは、第１図に示すように、圧電
変換素子２の前面部を覆う前面遮蔽板４１に、突部４３
を設けて圧電変換素子２を取り付け、前面遮蔽板４１に
設けた周壁部４６に背面遮蔽板４７を取り付けて圧電変
換素子２の背面部を覆い、周壁部４６に圧電変換素子２
の背面空間部４５を外気に通じさせる透孔（溝部４８）
を形成したものである。As shown in FIG. 1, the piezoelectric speaker of the present invention has a protrusion 43 on a front shielding plate 41 that covers the front surface of the piezoelectric transducer 2.
A rear shielding plate 47 is attached to the peripheral wall portion 46 provided on the front shielding plate 41 to cover the rear surface of the piezoelectric transducer 2.
A through hole (groove 48) that allows the back space 45 to communicate with the outside air.
was formed.
また、前面遮蔽板４１、突部４３および周壁部４６は、
合成樹脂を以て一体成形加工によって形成することがで
きる。In addition, the front shielding plate 41, the protrusion 43, and the peripheral wall 46 are
It can be formed by integral molding using synthetic resin.
圧電変換素子２は前面遮蔽板４１に設けた突部４３に取
り付けられているので、圧電変換素子２の前面部には突
部４３によって区画された前面空間部４０が形成されて
いる。また、圧電変換素子２は、前面遮蔽板４１に形成
された周壁部４６で包囲されているとともに、この周壁
部４６に取り付けた背面遮蔽板４７によって覆われてい
るので、圧電変換素子２の背面部には周壁部４６および
背面遮蔽板４７によって覆われた背面空間部４５が形成
されている。そして、背面空間部４５は、周壁部４６に
形成した透孔（溝部４８）によって外気に通じている。Since the piezoelectric transducer 2 is attached to the protrusion 43 provided on the front shielding plate 41, a front space 40 defined by the protrusion 43 is formed in the front face of the piezoelectric transducer 2. Furthermore, the piezoelectric transducer 2 is surrounded by a peripheral wall 46 formed on the front shielding plate 41 and is covered by a rear shielding plate 47 attached to the peripheral wall 46, so that the piezoelectric transducer 2 A rear space portion 45 covered by a peripheral wall portion 46 and a rear shielding plate 47 is formed in the portion. The back space portion 45 communicates with the outside air through a through hole (groove portion 48) formed in the peripheral wall portion 46.
したがって、圧電変換素子２は、前面空間部４０と背面
空間部４５とを以て自由振動を可能にされており、この
ような容器構造から音声など自然音についての再現性が
改善される。Therefore, the piezoelectric transducer 2 is allowed to freely vibrate using the front space 40 and the back space 45, and this container structure improves the reproducibility of natural sounds such as voices.
また、前面遮蔽板４１、突部４３および周壁部４６を合
成樹脂を以て一体成形加工によって形成すると、極めて
容易に、優れた再現性を持つ圧電スピーカが得られる。Furthermore, if the front shielding plate 41, the protrusion 43, and the peripheral wall 46 are integrally formed from synthetic resin, a piezoelectric speaker with excellent reproducibility can be obtained very easily.
第１図は、この発明の圧電スピーカの実施例を示す。 FIG. 1 shows an embodiment of the piezoelectric speaker of the present invention.
この圧電スピーカには、電気音響変換素子としての圧電
変換素子２が用いられており、この圧電変換素子２には
、電極を兼ねる円形の振動板２１の中心にセラミックな
どの円板状の圧電素子２２が固着されているとともに、
この圧電素子２２の表面にメタライズ処理などによって
設置された導電金属層からなる電極２３が設置されてい
る。圧電変換素子２は、圧電素子２２を中心にして振動
板２１および電極２３からなるサンドインチ構造を成し
ている。そして、振動板２１および電極２３には、リー
ド２４．２５が半田付けなどの電気的接続手段によって
接続され、音響振動に変換すべき電気信号がリード２４
．２５を通して加えられる。This piezoelectric speaker uses a piezoelectric transducer 2 as an electroacoustic transducer, and the piezoelectric transducer 2 includes a disk-shaped piezoelectric element made of ceramic or the like at the center of a circular diaphragm 21 that also serves as an electrode. 22 is fixed, and
An electrode 23 made of a conductive metal layer is provided on the surface of the piezoelectric element 22 by metallization or the like. The piezoelectric transducer 2 has a sandwich structure consisting of a diaphragm 21 and an electrode 23 with the piezoelectric element 22 at the center. Leads 24 and 25 are connected to the diaphragm 21 and the electrodes 23 by electrical connection means such as soldering, and electrical signals to be converted into acoustic vibrations are transmitted to the leads 24 and 25.
．． Added through 25.
この圧電変換素子２を収容する容器として合成樹脂など
によって形成されたスピーカケース４が設置されている
。このスピーカケース４には、圧電変換素子２を支持す
る支持部材を構成するとともに、圧電変換素子２の前面
部を覆って前面空間部４０を形成する前面遮蔽板４１が
設けられ、この前面遮蔽板４１の圧電変換素子２に対向
する面部には、圧電変換素子２が発生した音響を放射す
る複数の放射透孔４２が形成されている。前面遮蔽板４
１の背面部には、放射透孔４２を包囲する周回状を成す
円筒状の突部４３が形成されており、−この突部４３の
端面部に形成された段部４４に圧電変換素子２の振動板
２１が接着剤などを以て固着されている。突部４３は、
内径を振動板２１より小さくされ、外径を振動板２１よ
り大きくなるように設定され、段部４４が肉厚の中間に
なるように設定される。A speaker case 4 made of synthetic resin or the like is installed as a container for accommodating the piezoelectric transducer 2. This speaker case 4 is provided with a front shielding plate 41 that constitutes a support member that supports the piezoelectric transducer 2 and that covers the front surface of the piezoelectric transducer 2 to form a front space 40. A plurality of radiation holes 42 for radiating sound generated by the piezoelectric transducer 2 are formed in the surface portion 41 facing the piezoelectric transducer 2 . Front shielding plate 4
A circular cylindrical protrusion 43 surrounding the radiation hole 42 is formed on the back surface of the piezoelectric transducer 2 . A diaphragm 21 is fixed with adhesive or the like. The protrusion 43 is
The inner diameter is set to be smaller than the diaphragm 21, the outer diameter is set to be larger than the diaphragm 21, and the stepped portion 44 is set to be intermediate in thickness.
そして、前面遮蔽板４１の背面には、圧電変換素子２の
背面部に背面空間部４５を形成するために、突部４３か
ら離間した位置に突部４３より高い周壁部４６が形成さ
れており、この周壁部４６の頂部には、背面遮蔽板４７
が取り付けられて圧電変換素子２の背面部に形成される
背面空間部４５に外気を通じさせるための透孔を成す複
数の溝部４８が形成されている。実施例では、溝部４８
で形成したが、周壁部４６に透孔を直接形成してもよく
、開閉可能に形成して個数を任意に調整可能にしてもよ
い。On the back surface of the front shielding plate 41, a peripheral wall portion 46 higher than the protrusion 43 is formed at a position spaced apart from the protrusion 43 in order to form a back space portion 45 on the back surface of the piezoelectric transducer 2. , a rear shielding plate 47 is provided on the top of this peripheral wall portion 46.
A plurality of grooves 48 are formed to form through holes for allowing outside air to pass through the back space 45 formed on the back surface of the piezoelectric transducer 2 to which the piezoelectric transducer 2 is attached. In the embodiment, the groove 48
However, the through holes may be directly formed in the peripheral wall portion 46, or may be formed to be openable and closable so that the number of holes can be adjusted arbitrarily.
また、実施例では、前面遮蔽板４１が矩形形状であるた
め、その外形形状に合致した矩形の周壁部４６が形成さ
れており、前面遮蔽板４１には駆動回路６を設置するた
めの収容“部８が形成されている。この収容部８には、
前面遮蔽板４１を延長して前面板８１が形成されている
とともに、周壁部４６を延長して壁部８２．８３が形成
されている。In addition, in the embodiment, since the front shielding plate 41 has a rectangular shape, a rectangular peripheral wall portion 46 that matches the outer shape of the front shielding plate 41 is formed. A portion 8 is formed in this accommodating portion 8.
A front plate 81 is formed by extending the front shielding plate 41, and wall portions 82 and 83 are formed by extending the peripheral wall portion 46.
そして、第２図に示すように、周壁部４６および壁部８
２．８３には１、合成樹脂板、金属板、紙などによって
形成された背面遮蔽板４７が接着剤などで固着され、第
３図に示すように、圧電変換素子２の前面部には前面空
間部４０、その背面部には背面空間部４５が形成される
。Then, as shown in FIG. 2, the peripheral wall portion 46 and the wall portion 8
2.83, 1, a back shielding plate 47 formed of a synthetic resin plate, metal plate, paper, etc. is fixed with adhesive, etc., and as shown in FIG. A back space 45 is formed at the back of the space 40 .
このような構成によれば、前面遮蔽板４１に突部４３を
介して圧電変換素子２が設置され、圧電変換素子２の前
面部には、突部４３および前面遮蔽板４１によって区画
された前面空間部４０、圧電変換素子２の背面部には、
周壁部４６および背面遮蔽板４７によって区画された背
面空間部４５が設置されている。そして、背面空間部４
５は、複数の溝部４８からなる透孔を以て外気に通じて
いる。したがって、圧電変換素子２は、突部４３を支持
点として自由振動を生じ、リード２４．２５間に加えら
れた電気信号に応じた音響振動を生じ、人の声などにつ
いての再現性を改善することができる。According to such a configuration, the piezoelectric transducer 2 is installed on the front shielding plate 41 via the protrusion 43, and the front surface of the piezoelectric transducer 2 is divided by the protrusion 43 and the front shielding plate 41. In the space part 40 and the back part of the piezoelectric conversion element 2,
A back space 45 is provided that is partitioned by a peripheral wall 46 and a back shielding plate 47. And the back space part 4
5 communicates with the outside air through a through hole consisting of a plurality of grooves 48. Therefore, the piezoelectric transducer 2 generates free vibration using the protrusion 43 as a support point, and generates acoustic vibration according to the electrical signal applied between the leads 24 and 25, improving the reproducibility of human voices and the like. be able to.
圧電変換素子２は、チタン酸鉛とジルコン酸鉛の２成分
系セラミックを焼結して直径２８．５ｍｍ、厚さ０．０
５ｍｍの圧電素子２２を形成し、これを振動板２１とし
て直径４０ｍｍ、厚さ０．２０ｍｍの真鍮板に固着した
ものを用いた。これを合成樹脂で形成された第１図に示
すスピーカケース４に取り付け、また、同様の圧電変換
素子２を従来の円形の支持枠に取り付けたものを比較例
とした。The piezoelectric transducer 2 is made of sintered two-component ceramic of lead titanate and lead zirconate, and has a diameter of 28.5 mm and a thickness of 0.0 mm.
A 5 mm piezoelectric element 22 was formed and fixed to a brass plate 40 mm in diameter and 0.20 mm in thickness as the diaphragm 21. This was attached to a speaker case 4 shown in FIG. 1 made of synthetic resin, and a similar piezoelectric transducer 2 was attached to a conventional circular support frame as a comparative example.
実験によれば、この発明に係る圧電スピーカでは特性Ａ
、比較例では特性Ｂの周波数特性が得られ、比較例では
、低音域から高音域の各領域において急激なレベル低下
点Ｐｔ 、Ｐ２ 、Ｐｓ 、Ｐ４、Ｐ、、Ｐ、、Ｐ、が
現れているが、この発明の圧電スピーカでは、これらの
レベル低下点Ｐ Ｉ−Ｐ ？を補う比較的なだらかな特
性が得られている。特に、低音域におけるレベル低下点
Ｐ、 、Ｐ、 、中音域におけるレベル低下点Ｐ’ｓ、
Ｐｇの発生は確実に防止され、特に、高音域におけるレ
ベル低下点Ｐ、ではレベル低下の軽減、レベル低下点Ｐ
８、Ｐ、ではレベルの増強が見られる。According to experiments, the piezoelectric speaker according to the present invention has a characteristic A.
, In the comparative example, a frequency characteristic of characteristic B is obtained, and in the comparative example, sharp level drop points Pt , P2 , Ps , P4, P, , P, , P appear in each region from the bass range to the treble range. However, in the piezoelectric speaker of the present invention, these level drop points P I-P ? A relatively gentle characteristic that compensates for this has been obtained. In particular, level drop points P in the bass range, ,P, , level drop points P's in the midrange,
The occurrence of Pg is reliably prevented, especially at the level drop point P in the high frequency range.
At 8, P, an enhancement in level is seen.
このような特性を持つ各スピーカについて、人の声を再
生した場合、この発明の圧電スピーカが、音質、音色な
どの特徴を良く表し、聞き易いなどの優れた音響特性を
持つことが確認された。When the human voice was reproduced using each speaker with such characteristics, it was confirmed that the piezoelectric speaker of the present invention has excellent acoustic characteristics such as good reproduction of sound quality, timbre, etc., and easy listening. .
以上説明したように、この発明によれば、前面空間部と
、周壁部を以て区画されるとともに、周壁部に形成され
た透孔を以て外気に通じさせた背面空間部とを備え、突
部を支持点として圧電変換素子の自由振動を可能にした
ので、このような容器構造から音声など、自然音につい
て高音質で再現性が高いなどの優れた音響特性を得るこ
とができる。As explained above, according to the present invention, the front space and the back space are divided by the peripheral wall and communicated with outside air through the through holes formed in the peripheral wall, and support the protrusion. Since free vibration of the piezoelectric transducer is enabled, excellent acoustic characteristics such as high sound quality and high reproducibility of natural sounds such as voices can be obtained from such a container structure.
また、この発明によれば、前面遮蔽板、突部および周壁
部を合成樹脂を以て一体成形加工によって形成したので
、音響特性の優れた圧電スピーカを実現することができ
る。Further, according to the present invention, since the front shielding plate, the protrusion, and the peripheral wall are integrally molded from synthetic resin, it is possible to realize a piezoelectric speaker with excellent acoustic characteristics.
第１図はこの発明の圧電スピーカの実施例を示す分解斜
視図、第２図は第１図に示した圧電スピーカの組立斜視
図、第３図は第２図に示した圧電スピーカの■−■線断
面図、第４図は電気音響変換特性を示す図である。
２・・・圧電変換素子
４・・・スピーカケース
４０・・・前面空間部
４１・・・前面遮蔽板
４３・・・突部
４５・・・背面空間部
４６・・・周壁部
４７・・・背面遮蔽板
４８・・・溝部（透孔）Fig. 1 is an exploded perspective view showing an embodiment of the piezoelectric speaker of the present invention, Fig. 2 is an assembled perspective view of the piezoelectric speaker shown in Fig. 1, and Fig. 3 is an exploded perspective view of the piezoelectric speaker shown in Fig. 2. (2) Line sectional view, FIG. 4 is a diagram showing electroacoustic conversion characteristics. 2...Piezoelectric conversion element 4...Speaker case 40...Front space 41...Front shielding plate 43...Protrusion 45...Back space 46...Peripheral wall 47... Rear shielding plate 48...Groove (through hole)
Claims (2)
を設けて圧電変換素子を取り付け、前記前面遮蔽板に設
けた周壁部に背面遮蔽板を取り付けて前記圧電変換素子
の背面部を覆い、前記周壁部に前記圧電変換素子の背面
空間部を外気に通じさせる透孔を形成した圧電スピーカ
。(1) A protrusion is provided on a front shielding plate that covers the front surface of the piezoelectric transducer, and the piezoelectric transducer is attached to the front shielding plate, and a rear shielding plate is attached to the peripheral wall provided on the front shielding plate to attach the piezoelectric transducer to the rear surface of the piezoelectric transducer. a piezoelectric speaker, the piezoelectric speaker having a through hole formed in the peripheral wall portion to allow a back space portion of the piezoelectric transducer element to communicate with the outside air.
以て一体成形加工によって形成した請求項１記載の圧電
スピーカ。(2) The piezoelectric speaker according to claim 1, wherein the front shielding plate, the protrusion, and the peripheral wall are integrally formed of synthetic resin.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7064588A JPH01243698A (en) | 1988-03-24 | 1988-03-24 | Piezoelectric loudspeaker |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7064588A JPH01243698A (en) | 1988-03-24 | 1988-03-24 | Piezoelectric loudspeaker |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01243698A true JPH01243698A (en) | 1989-09-28 |
| JPH0554320B2 JPH0554320B2 (en) | 1993-08-12 |
Family
ID=13437592
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7064588A Granted JPH01243698A (en) | 1988-03-24 | 1988-03-24 | Piezoelectric loudspeaker |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01243698A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002536891A (en) * | 1999-01-26 | 2002-10-29 | コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ | Apparatus for housing an audio transformer and having a housing with a passage |
| JP2021040285A (en) * | 2019-09-05 | 2021-03-11 | Tdk株式会社 | Acoustic device |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09186A (en) * | 1995-06-16 | 1997-01-07 | Makoto Suzuki | Packing sheet for cooked rice food and packed cooked rice food |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63125500U (en) * | 1987-02-09 | 1988-08-16 |
-
1988
- 1988-03-24 JP JP7064588A patent/JPH01243698A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63125500U (en) * | 1987-02-09 | 1988-08-16 |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002536891A (en) * | 1999-01-26 | 2002-10-29 | コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ | Apparatus for housing an audio transformer and having a housing with a passage |
| JP2021040285A (en) * | 2019-09-05 | 2021-03-11 | Tdk株式会社 | Acoustic device |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0554320B2 (en) | 1993-08-12 |
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