JPH03285498A - Piezoelectric acoustic device - Google Patents
Piezoelectric acoustic deviceInfo
- Publication number
- JPH03285498A JPH03285498A JP2087206A JP8720690A JPH03285498A JP H03285498 A JPH03285498 A JP H03285498A JP 2087206 A JP2087206 A JP 2087206A JP 8720690 A JP8720690 A JP 8720690A JP H03285498 A JPH03285498 A JP H03285498A
- Authority
- JP
- Japan
- Prior art keywords
- diaphragm
- resonator
- acoustic device
- piezoelectric
- piezoelectric acoustic
- 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
- 230000002093 peripheral effect Effects 0.000 claims abstract description 20
- 239000000853 adhesive Substances 0.000 claims abstract description 16
- 230000001070 adhesive effect Effects 0.000 claims abstract description 16
- 239000013464 silicone adhesive Substances 0.000 abstract description 7
- 239000000919 ceramic Substances 0.000 abstract description 3
- 239000003795 chemical substances by application Substances 0.000 abstract 1
- 239000002184 metal Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000004080 punching Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 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
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R2307/00—Details of diaphragms or cones for electromechanical transducers, their suspension or their manufacture covered by H04R7/00 or H04R31/003, not provided for in any of its subgroups
- H04R2307/201—Damping aspects of the outer suspension of loudspeaker diaphragms by addition of additional damping means
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R2307/00—Details of diaphragms or cones for electromechanical transducers, their suspension or their manufacture covered by H04R7/00 or H04R31/003, not provided for in any of its subgroups
- H04R2307/207—Shape aspects of the outer suspension of loudspeaker diaphragms
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
本発明は、圧電素子を用いた圧電リンガ−圧電送受話器
等の圧電音響装置に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a piezoelectric acoustic device such as a piezoelectric ringer-piezoelectric handset using a piezoelectric element.
［従来の技術］
圧電音響装置の従来例を第５図と第６図により説明する
と、円板状の金属板からなる振動板５０片方の主面に、
圧電セラミクスの膜とその上に形成した電極からなる圧
電素子６を形成し、この振動板５を円形の容器状の共鳴
器ｌの中に収納し、同振動板５の周囲を共鳴器ｌの内周
壁部に支持してなる。前記共鳴器■は第５図において下
面側が蓋体７で閉じられると共に、共鳴器ｌの土壁中央
と蓋体７の中央に各々放音孔１０．４が開設されている
。[Prior art] A conventional example of a piezoelectric acoustic device will be explained with reference to FIGS.
A piezoelectric element 6 consisting of a piezoelectric ceramic film and an electrode formed on the piezoelectric element 6 is formed, and this diaphragm 5 is housed in a circular container-shaped resonator l. It is supported on the inner peripheral wall. As shown in FIG. 5, the lower surface of the resonator (2) is closed with a lid 7, and a sound emitting hole 10.4 is provided at the center of the earthen wall of the resonator (1) and at the center of the lid (7).
このような圧電音響装置では、共鳴器ｌの内周に段部１
ｃを形成し、ここに弾性を育する接着剤１６、例えばシ
リコーン系接着剤を介して前記振動板５０周辺部を接着
固定する手段がとられている。シリコーン系接着剤は、
硬化後も適当な弾性を有し、振動板５の周辺部を弾性的
に支持するため、振動板５の周辺部を共鳴器１の内周に
剛着した場合に比べて良好な音響特性が得られる。In such a piezoelectric acoustic device, a stepped portion 1 is provided on the inner periphery of the resonator l.
c, and the periphery of the diaphragm 50 is adhesively fixed thereto using an adhesive 16 that increases elasticity, such as a silicone adhesive. Silicone adhesive is
Since it has appropriate elasticity even after hardening and elastically supports the peripheral part of the diaphragm 5, it has better acoustic characteristics than when the peripheral part of the diaphragm 5 is rigidly attached to the inner periphery of the resonator 1. can get.
［発明が解決しようとする課題］
しかしながら、前記シリコーン系接着剤を用いて振動板
５０周辺部を共鳴器ｌの内周に固着する手段では、接着
剤１６を共鳴器１０段部１ｃに塗布する量や位置により
、製品の品質にばらつきが生じやすいという課題があっ
た。すなわち、塗布量が過多であると、その上に振動板
５０周辺部を載せて加圧した際、接着剤１６が段部１ｃ
から多量に流れ出して、外観不良及び接着不良となる。[Problems to be Solved by the Invention] However, in the method of fixing the periphery of the diaphragm 50 to the inner periphery of the resonator l using the silicone adhesive, the adhesive 16 is applied to the stepped portion 1c of the resonator 10. There was a problem in that the quality of the product tends to vary depending on the amount and location. In other words, if the applied amount is too large, when the periphery of the diaphragm 50 is placed on top of it and pressure is applied, the adhesive 16 will not adhere to the stepped portion 1c.
A large amount flows out, resulting in poor appearance and poor adhesion.
また、塗布量が過少であると、振動板５が確実に接着さ
れない。さらに、塗布位置が、段部１ｃの内周側に偏る
と、例えば第６図（ａ）で示すように、接着剤１６が段
部の内側にはみ出し、外周側が少な（なる。他方、塗布
位置が、段部１ｃの外周側に偏ると、例えば第６図（ｂ
）で示すように、接着剤１６が段部の外側にはみ出し、
内周側が少なくなる。このような場合は、何れも接着不
良となることが多い。Moreover, if the amount of application is too small, the diaphragm 5 will not be reliably bonded. Furthermore, if the application position is biased toward the inner circumference of the stepped portion 1c, as shown in FIG. However, if it is biased toward the outer periphery of the stepped portion 1c, for example, as shown in FIG.
), the adhesive 16 protrudes outside the step,
The inner circumferential side becomes smaller. In such cases, poor adhesion often occurs.
本発明は、前記従来の圧電音響装置における問題を解決
することを目的とする。The present invention aims to solve the problems in the conventional piezoelectric acoustic devices.
［課題を解決するための手段］
すなわち、前記目的を達成するため、本発明において採
用した手段の要旨は、第一に、主面に圧電素子６が形成
された振動板５０周辺部を、共鳴器１の内周壁に形成し
た段部１ｃに弾性を有する接着剤で接着した圧電音響装
置において、前記振動板５の周辺部と共鳴器ｌの段部１
ｃとの接着される面の少なくとも何れか一方に放射状の
凹凸溝１５．１８を形成した圧電音響装置である。[Means for Solving the Problems] That is, the gist of the means adopted in the present invention in order to achieve the above object is as follows: First, the periphery of the diaphragm 50 on which the piezoelectric element 6 is formed on the main surface is made to resonate. In a piezoelectric acoustic device in which a stepped portion 1c formed on the inner circumferential wall of a resonator 1 is bonded with an elastic adhesive, the peripheral portion of the diaphragm 5 and the stepped portion 1 of the resonator l
This is a piezoelectric acoustic device in which radial uneven grooves 15 and 18 are formed on at least one of the surfaces to be bonded to c.
第二に、主面に圧電素子６が形成された振動板５の周辺
部を、共鳴器１の内周壁に形成した段部１ｃに弾性を有
する接着剤で接着した圧電音響装置において、前記振動
板５の周辺部に鋸刃状の凹凸１７を形成した圧電音響装
置である。Second, in a piezoelectric acoustic device in which the peripheral part of the diaphragm 5 on which the piezoelectric element 6 is formed on the main surface is adhered to the step part 1c formed on the inner circumferential wall of the resonator 1 with an elastic adhesive, the vibration This is a piezoelectric acoustic device in which saw blade-shaped unevenness 17 is formed on the periphery of the plate 5.
［作 用コ
前記第一の手段による圧電音響装置では、振動板５の周
辺部と共鳴器１の段部１ｃとの接着される面の少なくと
も何れか一方に放射状の凹凸溝１５．１８を形成してい
るため、弾性を有する接着剤１６を塗布した共鳴器ｌの
段部１ｃに振動板５の周辺部を載せて加圧したとき、前
記凹凸溝１５．１８を通して、接着剤１６が振動板５の
外周側から内周側或は内周側から外周側へと円滑に流れ
る。これにより、接着剤１６が共鳴器Ｉの段部１ｃの外
周側或は内周側に多少偏って塗布されても、シリコン系
接着剤が少ない方へと移動し、結果的に常に一定の状態
で振動板５０周辺部が接着されるようになる。[Function] In the piezoelectric acoustic device according to the first means, radial uneven grooves 15 and 18 are formed on at least one of the surfaces to be bonded between the peripheral portion of the diaphragm 5 and the step portion 1c of the resonator 1. Therefore, when the peripheral part of the diaphragm 5 is placed on the stepped part 1c of the resonator l coated with an elastic adhesive 16 and pressurized, the adhesive 16 passes through the uneven grooves 15 and 18 and is applied to the diaphragm. The water flows smoothly from the outer circumferential side to the inner circumferential side or from the inner circumferential side to the outer circumferential side. As a result, even if the adhesive 16 is applied somewhat unevenly to the outer or inner periphery of the stepped portion 1c of the resonator I, the amount of silicone adhesive moves toward the side with less amount, and as a result, the state is always constant. The periphery of the diaphragm 50 is then bonded.
以上の点は、振動板５０周辺部に鋸刃状の凹凸１７を形
成した第二の手段による圧電者Ｗ装置でも同様である。The above points also apply to the piezoelectric W device according to the second means in which sawtooth-shaped unevenness 17 is formed on the periphery of the diaphragm 50.
［実 施 例］ 次に、本発明の実施例について具体的に説明する。[Example] Next, examples of the present invention will be specifically described.
第１図と第２図に示されたように、圧電音響装置は、共
鳴器ｌの中に、圧電素子６を有する振動板５を収納して
なる。As shown in FIGS. 1 and 2, the piezoelectric acoustic device includes a diaphragm 5 having a piezoelectric element 6 housed in a resonator l.
共鳴器！はプラスチックや金属で形成され、この共鳴器
ｌの外周辺の両側に突起部１ａ、１ｂが形成され、この
突起部１ａ、ｌｂから端子２．３が下方へ突設されると
共に、該端子２．３に接続された可撓性のある接続ビン
８．９が共鳴器Ｉの内側に延設されている。また、この
共鳴器１の内周壁の下部に段部１ｃが形成され、土壁の
中央には、放音孔１０が開設されている。Resonator! is made of plastic or metal, and protrusions 1a and 1b are formed on both sides of the outer periphery of the resonator l, from which terminals 2.3 protrude downwardly. A flexible connecting pin 8.9 connected to .3 extends inside the resonator I. Further, a stepped portion 1c is formed at the lower part of the inner circumferential wall of the resonator 1, and a sound emitting hole 10 is provided in the center of the earthen wall.
振動板５は金属板からなり、その下面に圧電セラミック
膜と電極膜とからなる圧電素子６が形成されている。ま
た、振動板５の周辺部には、放射状に細かい凹凸溝１５
が形成されている。The diaphragm 5 is made of a metal plate, and a piezoelectric element 6 made of a piezoelectric ceramic film and an electrode film is formed on its lower surface. Further, the periphery of the diaphragm 5 is provided with radially fine uneven grooves 15.
is formed.
この振動板５は、前記周辺部がシリコーン系接着剤等の
弾性を有する接着剤１６で前記共鳴器ｌの段部１ｃに接
着され、保持される。例えば、共鳴器１０段部１ｃに未
硬化のシリコーン系接着剤１６を塗布し、ここに振動板
５の周辺部を載せて加圧し、接着剤１６を硬化させる。The diaphragm 5 is held at its peripheral portion by being adhered to the stepped portion 1c of the resonator 1 with an elastic adhesive 16 such as a silicone adhesive. For example, an uncured silicone adhesive 16 is applied to the stepped portion 1c of the resonator 10, and the peripheral portion of the diaphragm 5 is placed thereon and pressure is applied to harden the adhesive 16.
第３図（ａ）と（ｂ）に、前記凹凸溝１５の例が示され
ており、同図（ａ）では、上端が尖った山形状に形成さ
れた６峰が振動板５の周辺部に概ね一定の間隔で放射状
に形成され、これによって、振動板５０周辺部の下面に
凹凸溝１５が形成されている。また、同図ｃｂ＞では、
上端が円形山形状に形成された６峰が振動板５の周辺部
に概ね一定の間隔で放射状に形成され、これによって、
振動板５の周辺部の下面に凹凸溝１５が形成されている
。この他、矩形の山形状に６峰を形成したり、周辺部を
波形に加工する等、様々な形状の凹凸溝を例として挙げ
ることができる。FIGS. 3(a) and 3(b) show an example of the uneven grooves 15, and in FIG. The grooves 15 are formed radially at approximately constant intervals, thereby forming uneven grooves 15 on the lower surface of the periphery of the diaphragm 50. Also, in the same figure cb>,
Six peaks each having a circular peak shape at the upper end are formed radially around the periphery of the diaphragm 5 at approximately constant intervals.
An uneven groove 15 is formed on the lower surface of the peripheral portion of the diaphragm 5. Other examples include uneven grooves of various shapes, such as forming six peaks in a rectangular mountain shape or processing the peripheral portion into a wave shape.
このような凹凸溝１５を存する振動板５は、例えば、振
動板５を打抜加工する際に、周辺部を溝状にプレス加工
することにより製造することができる。The diaphragm 5 having such uneven grooves 15 can be manufactured, for example, by pressing the peripheral portion into a groove shape when punching the diaphragm 5.
第３図（ｃ）と（ｄ）は、振動板５の周辺部に鋸刃（或
は歯車）状の凹凸１７を形成した例であり、同図（ｃ）
では、矩形刃状のものが、同図（ｄ）では、三角刃状の
ものが各々示されている。3(c) and 3(d) are examples in which saw blade (or gear) shaped unevenness 17 is formed on the periphery of the diaphragm 5.
, a rectangular blade shape is shown, and FIG. 3(d) shows a triangular blade shape.
前記のような凹凸溝は、振動板５の周辺部が載せられる
共鳴器１の段部１ｃに形成してもよく、第４図では、こ
の段部１ｃに溝１８．１８・・・を形成した例が示され
ている。この段部１ｃの凹凸溝１８．１８・・・と、振
動板５の凹凸溝１５または凹凸１７は、併用することが
できる。The uneven grooves as described above may be formed in the stepped portion 1c of the resonator 1 on which the peripheral portion of the diaphragm 5 is placed, and in FIG. An example is shown. The uneven grooves 18, 18... of the stepped portion 1c and the uneven grooves 15 or the uneven grooves 17 of the diaphragm 5 can be used together.
このようにして振動板５が取り付けられた共鳴器ｌの下
面は、第１図で示されたように、蓋体７で閉じられてい
る。この蓋体７で共鳴器ｌの下面を閉じる前に、前記接
続ビン８．９が上方へ折り曲げられ、その先端が振動板
５と圧電素子６０表面に各々半田付され、端子２．３が
振動板５と圧電素子６に各々接続される。この蓋体７の
中央には、円形の放音孔４が開設されている。The lower surface of the resonator l, to which the diaphragm 5 is attached in this manner, is closed with a lid 7, as shown in FIG. Before closing the lower surface of the resonator l with the lid body 7, the connection bottle 8.9 is bent upward, its tips are soldered to the surface of the diaphragm 5 and the piezoelectric element 60, respectively, and the terminal 2.3 is vibrated. They are connected to the plate 5 and the piezoelectric element 6, respectively. A circular sound emitting hole 4 is provided in the center of the lid 7.
［発明の効果コ
以上説明した通り、本発明では、振動板の共鳴器への取
付が容易であり、且つ常にほぼ一定の状態で振動板の周
辺部を接着し、支持することができるので、生産性と歩
留りが高い圧電音響装置が提供できる。[Effects of the Invention] As explained above, in the present invention, the diaphragm can be easily attached to the resonator, and the peripheral part of the diaphragm can be always bonded and supported in a substantially constant state. A piezoelectric acoustic device with high productivity and yield can be provided.
第１図は、本発明の実施例を示す圧電音響装置の縦断側
面図、第２図は、同圧電音響装置の分解縦断側面図、第
３図（ａ）〜（ｄ）は、第２図のＡ部形状の各個を示す
要部拡大斜視図、第４図は、共鳴器の段部の例を示す要
部拡大斜視図、第５図は、従来例を示す圧電音響装置の
縦断側面図、第６図（ａＬ （ｂ）は、同圧電音響装
置の要部拡大縦断側面図である。
１・・・共鳴器 １ｃ・・・共鳴器の段部 ５・・・振
動板６・・・圧電素子 ７・・・蓋体 １１・・・リン
グ １５・・・振動板の周辺部の凹凸溝 １６・・・接
着剤１７・・・振動板の周辺部の凹凸 ＩＯ・・・共鳴
器の段部の溝FIG. 1 is a longitudinal sectional side view of a piezoelectric acoustic device showing an embodiment of the present invention, FIG. 2 is an exploded longitudinal sectional side view of the piezoelectric acoustic device, and FIGS. 3(a) to 3(d) are FIG. FIG. 4 is an enlarged perspective view of the main parts showing an example of the step part of the resonator, and FIG. 5 is a longitudinal side view of the piezoelectric acoustic device showing a conventional example. , FIG. 6 (aL (b) is an enlarged longitudinal sectional side view of the main parts of the same piezoelectric acoustic device. 1... Resonator 1c... Step part of resonator 5... Vibration plate 6... Piezoelectric element 7... Lid 11... Ring 15... Irregular grooves on the periphery of the diaphragm 16... Adhesive 17... Irregularities on the periphery of the diaphragm IO... Resonator steps groove of the part
Claims (2)
を、共鳴器１の内周壁に形成した段部１ｃに弾性を有す
る接着剤で接着した圧電音響装置において、前記振動板
５の周辺部と共鳴器１の段部１ｃとの接着される面の少
なくとも何れか一方に放射状の凹凸溝１５、１８を形成
してなることを特徴とする圧電音響装置。(1) In a piezoelectric acoustic device in which the peripheral part of the diaphragm 5 having the piezoelectric element 6 formed on the main surface is adhered to the step part 1c formed on the inner circumferential wall of the resonator 1 with an elastic adhesive, the diaphragm A piezoelectric acoustic device characterized in that radial grooves 15 and 18 are formed on at least one of the surfaces to be bonded between the peripheral portion of the resonator 5 and the stepped portion 1c of the resonator 1.
を、共鳴器１の内周壁に形成した段部１ｃに弾性を有す
る接着剤で接着した圧電音響装置において、前記振動板
５の周辺部に鋸刃状の凹凸１７を形成してなることを特
徴とする圧電音響装置。(2) In a piezoelectric acoustic device in which a peripheral portion of a diaphragm 5 having a piezoelectric element 6 formed on its main surface is adhered to a step 1c formed on an inner circumferential wall of a resonator 1 with an elastic adhesive, the diaphragm A piezoelectric acoustic device characterized in that a saw blade-like unevenness 17 is formed on the periphery of the piezoelectric acoustic device 5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2087206A JPH03285498A (en) | 1990-03-31 | 1990-03-31 | Piezoelectric acoustic device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2087206A JPH03285498A (en) | 1990-03-31 | 1990-03-31 | Piezoelectric acoustic device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03285498A true JPH03285498A (en) | 1991-12-16 |
Family
ID=13908487
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2087206A Pending JPH03285498A (en) | 1990-03-31 | 1990-03-31 | Piezoelectric acoustic device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03285498A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1881736A2 (en) * | 2006-07-20 | 2008-01-23 | Hosiden Corporation | Piezoelectric electroacoustic transducing device |
| KR20160024459A (en) * | 2014-08-26 | 2016-03-07 | 서울시립대학교 산학협력단 | Plate Speaker |
| KR20160063947A (en) * | 2014-11-27 | 2016-06-07 | 서울시립대학교 산학협력단 | Plate Speaker |
| KR20160111096A (en) * | 2015-03-16 | 2016-09-26 | 서울시립대학교 산학협력단 | Speaker |
-
1990
- 1990-03-31 JP JP2087206A patent/JPH03285498A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1881736A2 (en) * | 2006-07-20 | 2008-01-23 | Hosiden Corporation | Piezoelectric electroacoustic transducing device |
| EP1881736A3 (en) * | 2006-07-20 | 2010-05-05 | Hosiden Corporation | Piezoelectric electroacoustic transducing device |
| KR20160024459A (en) * | 2014-08-26 | 2016-03-07 | 서울시립대학교 산학협력단 | Plate Speaker |
| KR20160063947A (en) * | 2014-11-27 | 2016-06-07 | 서울시립대학교 산학협력단 | Plate Speaker |
| KR20160111096A (en) * | 2015-03-16 | 2016-09-26 | 서울시립대학교 산학협력단 | Speaker |
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