JPS6312399Y2 - - Google Patents
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- Publication number
- JPS6312399Y2 JPS6312399Y2 JP16303281U JP16303281U JPS6312399Y2 JP S6312399 Y2 JPS6312399 Y2 JP S6312399Y2 JP 16303281 U JP16303281 U JP 16303281U JP 16303281 U JP16303281 U JP 16303281U JP S6312399 Y2 JPS6312399 Y2 JP S6312399Y2
- Authority
- JP
- Japan
- Prior art keywords
- piezoelectric buzzer
- resonator
- resonance
- sound
- 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.)
- Expired
Links
- 238000010586 diagram Methods 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
- 239000000057 synthetic resin Substances 0.000 description 1
Landscapes
- Piezo-Electric Transducers For Audible Bands (AREA)
Description
【考案の詳細な説明】
この考案は圧電ブザーと共鳴器を組合わせた圧
電ブザー発音装置に関する。[Detailed Description of the Invention] This invention relates to a piezoelectric buzzer sounding device that combines a piezoelectric buzzer and a resonator.
従来、圧電ブザー発音装置としては第１図に示
すものが知られている。即ち、図中１は振動板
で、この振動板１の下面側中央部には圧電素子２
が接着されて圧電ブザー３を構成している。この
振動板１と圧電素子２は夫々円板状をなすもの
で、振動板１の周縁部は共鳴箱４に固定されてい
る。圧電ブザー３と共鳴箱４の壁部で囲まれた共
鳴箱４の内部には共鳴空間５が構成されている。
この共鳴空間５を構成する共鳴箱４の壁部、すな
わち圧電ブザー３の上面側と対向する壁部には放
音孔６が形成してある。したがつて、圧電ブザー
３の上面側には共鳴空間５と放音孔６によつて所
謂HELMHOLZの共鳴器である共鳴器７が構成
されている。 2. Description of the Related Art Conventionally, as a piezoelectric buzzer sounding device, one shown in FIG. 1 is known. That is, 1 in the figure is a diaphragm, and a piezoelectric element 2 is located at the center of the lower surface of this diaphragm 1.
are adhered to form the piezoelectric buzzer 3. The diaphragm 1 and the piezoelectric element 2 each have a disk shape, and the periphery of the diaphragm 1 is fixed to a resonance box 4. A resonance space 5 is formed inside the resonance box 4 surrounded by the piezoelectric buzzer 3 and the walls of the resonance box 4.
A sound emitting hole 6 is formed in a wall portion of the resonance box 4 constituting the resonance space 5, that is, a wall portion facing the upper surface side of the piezoelectric buzzer 3. Therefore, on the upper surface side of the piezoelectric buzzer 3, a resonator 7, which is a so-called HELMHOLZ resonator, is formed by the resonance space 5 and the sound emission hole 6.
そして上記振動板１と圧電素子２には各々リー
ド線（図示略）が接続されて外部に引き出され、
圧電ブザー３に対し、例えば矩形波信号が印加さ
れる。 Lead wires (not shown) are connected to the diaphragm 1 and the piezoelectric element 2, respectively, and drawn out to the outside.
For example, a rectangular wave signal is applied to the piezoelectric buzzer 3.
第３図は上述した構成の従来の圧電ブザー発音
装置に矩形波信号を印加した場合の音圧レベル周
波数特性の一例を示す。同図のように、この特性
は圧電ブザー３の共振周波数B（この場合、1500
Hz）と、共鳴器７の共鳴周波数1（この場合、
3000Hz）と、上記共振周波数B、共鳴周波数1の
各々１／３，１／５，１／７，…１／ｎ（ｎは奇数）の
各周
波数にピークが生じて全体的にピークとデイツプ
が激しい特性である。このため音圧も全体的に低
いという欠点がある。 FIG. 3 shows an example of sound pressure level frequency characteristics when a rectangular wave signal is applied to the conventional piezoelectric buzzer sounding device having the above-described configuration. As shown in the figure, this characteristic corresponds to the resonance frequency B of the piezoelectric buzzer 3 (in this case, 1500
Hz) and the resonant frequency 1 of the resonator 7 (in this case,
3000Hz) and 1/3, 1/5, 1/7, ... 1/n (n is an odd number) of the above-mentioned resonance frequency B and resonance frequency 1, respectively, with peaks and dips occurring overall. It is a violent characteristic. Therefore, there is a drawback that the sound pressure is generally low.
この考案は上述した事情を改善するためになさ
れたもので、その目的とするところは、圧電ブザ
ーの上下画面に対し各々共鳴器を設けると共に、
圧電ブザーの共振周波数と第１の共鳴器の共鳴周
波数との間に第２の共鳴器の共鳴周波数を設定す
るようにして、音圧−周波数特性をフラツトな特
性に近づけ、音圧レベルが全体的に向上するよう
にした圧電ブザー発音装置を提供することにあ
る。 This invention was made to improve the above-mentioned situation, and its purpose was to provide resonators for the upper and lower screens of the piezoelectric buzzer, and to
By setting the resonant frequency of the second resonator between the resonant frequency of the piezoelectric buzzer and the resonant frequency of the first resonator, the sound pressure-frequency characteristics are brought close to flat characteristics, and the overall sound pressure level is An object of the present invention is to provide a piezoelectric buzzer sounding device which is improved in performance.
以下、第２図、第４図ないし第６図を参照して
この考案の一実施例を説明する。第２図におい
て、振動板１１の下面側中央部には圧電素子１２
が一体的に接着され、圧電ブザー１３が構成され
る。この圧電ブザー１３は第１図の圧電ブザー３
と同様の構成であり、振動板１１の周縁部が共鳴
箱１４に固定されている。この圧電ブザー１３の
上面側および下面側にはHELMHOLZの共鳴器
である第１の共鳴器１５、第２の共鳴器１６が
各々設けられている。即ち、第１の共鳴器１５は
圧電ブザー１３の上面側に設けられた共鳴空間１
７と、共鳴空間１７に面する共鳴箱１４の壁部に
形成された円形の放音孔１８とから構成されてい
る。同様に、第２の共鳴器１６は圧電ブザー１３
の下面側に設けられた共鳴空間１９と円形の放音
孔２０とから構成されている。なお、第２図に示
す実施例の圧電ブザー発音装置の全体形状は円形
状をなすものである。また振動板１１と圧電素子
１２には各々リード線（図示略）が接続されて外
部に引き出され、圧電ブザー１３に矩形波信号が
印加される。 An embodiment of this invention will be described below with reference to FIG. 2 and FIGS. 4 to 6. In FIG. 2, a piezoelectric element 12 is located at the center of the lower surface of the diaphragm 11.
are integrally adhered to form the piezoelectric buzzer 13. This piezoelectric buzzer 13 is the piezoelectric buzzer 3 in FIG.
The configuration is similar to that in which the peripheral edge of the diaphragm 11 is fixed to the resonance box 14. A first resonator 15 and a second resonator 16, which are HELMHOLZ resonators, are provided on the upper and lower surfaces of the piezoelectric buzzer 13, respectively. That is, the first resonator 15 is a resonance space 1 provided on the upper surface side of the piezoelectric buzzer 13.
7, and a circular sound emitting hole 18 formed in the wall of the resonance box 14 facing the resonance space 17. Similarly, the second resonator 16 is connected to the piezoelectric buzzer 13
It consists of a resonance space 19 provided on the lower surface side and a circular sound emitting hole 20. Note that the overall shape of the piezoelectric buzzer sounding device of the embodiment shown in FIG. 2 is circular. Further, lead wires (not shown) are connected to the vibration plate 11 and the piezoelectric element 12, respectively, and drawn out to the outside, and a rectangular wave signal is applied to the piezoelectric buzzer 13.
ここで、上記圧電ブザー１３の共振周波数B、
第１の共鳴器１５および第２の共鳴器１６の共鳴
周波数1，2は次のように設定される。即ち、先
ず圧電ブザー１３の共振周波数Bと第１の共鳴器
１５の共鳴周波数1との関係がB＜1となるよう
にHELMHOLZの共鳴器の計算式（後述）にし
たがつて第１の共鳴器１５を構成する。次に第２
の共鳴器１６の共鳴周波数2が上記周波数B，1
との間になるように第２の共鳴器１６を構成す
る。 Here, the resonance frequency B of the piezoelectric buzzer 13,
The resonance frequencies 1 and 2 of the first resonator 15 and the second resonator 16 are set as follows. That is, first, the first resonance is calculated according to the HELMHOLZ resonator calculation formula (described later) so that the relationship between the resonant frequency B of the piezoelectric buzzer 13 and the resonant frequency 1 of the first resonator 15 is B < 1 . A container 15 is configured. Then the second
The resonant frequency 2 of the resonator 16 is the above frequency B , 1
The second resonator 16 is configured so as to be located between.
したがつて、周波数の関係はB＜2＜1とな
る。 Therefore, the frequency relationship is B < 2 < 1 .
次に、HELMHOLZの共鳴器について説明す
ると、その共鳴周波数は次式(1)で求められる。 Next, explaining the HELMHOLZ resonator, its resonant frequency is determined by the following equation (1).
但し、Ｃ＝音の速さ（ｍ／sec）、π＝円周率、
Ｇ＝放音孔の導伝率、Ｖ＝共鳴空間の体積（m3）、
また放音孔の導電率Ｇは、放音孔が円形の場合、
次式(2)により求められる。 However, C = speed of sound (m/sec), π = pi,
G = conductivity of sound emission hole, V = volume of resonance space (m 3 ),
In addition, the conductivity G of the sound emission hole is, when the sound emission hole is circular,
It is determined by the following formula (2).
Ｇ＝πa2／ｌ＋π／２ａ （ｍ） ……(2)
但し、ａ＝放音孔の半径（ｍ）、ｌ＝放音孔の
長さ〔即ち、共鳴箱の肉厚〕（ｍ）。 G=πa 2 /l+π/2a (m) ...(2) where a=radius of the sound emission hole (m), l=length of the sound emission hole [i.e., wall thickness of the resonance box] (m).
いま、上記実施例において圧電ブザー１３の共
振周波数Bが1500Hzである場合、例えば下記の寸
法によつて第１の共鳴器１５、第２の共鳴器１６
を夫々設計する。但し、第２図に示すように、第
１の共鳴器１５、第２の共鳴器１６の共鳴空間１
７，１９の内径をa1，a2、厚みをd1，d2、放音孔
１８，２０の直径をb1，b2、長さをl1，l2とした
とき、
a1＝a2＝0.025（ｍ）、b1＝0.004（ｍ）、b2＝
0.0036（ｍ）、l1＝l2＝0.0015（ｍ）、d1＝0.0016
（ｍ）、d2＝0.0022（ｍ）とする。この実施例にお
いて、共鳴周波数1，2の設計値は上記(1)，(2)式
から、
1＝3177（Hz）
2＝2525（Hz）
となる。一般に、実際の共鳴周波数は設計値より
低くなり、上述した設計による圧電ブザー発音装
置の特性は第４図のようになつた。 Now, in the above embodiment, if the resonance frequency B of the piezoelectric buzzer 13 is 1500Hz, the first resonator 15 and the second resonator 16 are
Design each. However, as shown in FIG. 2, the resonance space 1 of the first resonator 15 and the second resonator 16
When the inner diameters of the holes 7 and 19 are a 1 and a 2 , the thicknesses are d 1 and d 2 , the diameters of the sound emission holes 18 and 20 are b 1 and b 2 , and the lengths are l 1 and l 2 , a 1 = a 2 = 0.025 (m), b 1 = 0.004 (m), b 2 =
0.0036 (m), l 1 = l 2 = 0.0015 (m), d 1 = 0.0016
(m), d 2 =0.0022 (m). In this embodiment, the design values of resonance frequencies 1 and 2 are as follows from equations (1) and (2) above: 1 = 3177 (Hz) 2 = 2525 (Hz). Generally, the actual resonant frequency is lower than the designed value, and the characteristics of the piezoelectric buzzer sounding device designed as described above are as shown in FIG.
即ち、第４図はこの実施例の圧電ブザー発音装
置の上記圧電ブザー１３に矩形波信号を印加した
場合の音圧レベル−周波数特性を示している。そ
して、各周波数B，1，2の関係は上述したよう
に、B＜2＜1となつている。このように各周波
数B，1，2は1とBの間に2がくるように設計
したので、各周波数B，1，2の１／３，１／５，
１／７，
…，１／ｎ（ｎは奇数）に表われるピークとデイ
ツプとが相互に重つて打消されることになり、全
体的にフラツトな安定した特性となつて音圧レベ
ルが従来に比べ大幅に増加した。 That is, FIG. 4 shows the sound pressure level-frequency characteristic when a rectangular wave signal is applied to the piezoelectric buzzer 13 of the piezoelectric buzzer sounding device of this embodiment. As described above, the relationship between the frequencies B , 1 , and 2 is B < 2 < 1 . In this way, each frequency B , 1 , 2 is designed so that 2 is between 1 and B , so 1/3, 1/5, and 1/5 of each frequency B , 1 , and 2 are
The peaks and dips appearing at 1/7, ..., 1/n (where n is an odd number) overlap and cancel each other out, resulting in an overall flat and stable characteristic, and the sound pressure level becomes lower than before. There was a significant increase compared to
第５図および第６図は上記実施例の圧電ブザー
発音装置を携帯用電子時計に内蔵した例を示して
いる。第５図はその表面側、また第６図は裏面側
を示す外観図である。第５図において、携帯用電
子時計のケース３１の上面には表示部３２、操作
キー３３、第１の放音孔３４とが設けられてい
る。上記表示器３２は例えば液晶表示素子から成
り、時刻表示が行われる。また操作キー３３は時
刻セツト等を行う。さらに、第１の放音孔３４は
ケース内に内蔵した上記圧電ブザー発音装置（図
示略）が、同様に内蔵されている時計回路（図示
略）により駆動制御されてアラーム時刻等におい
てアラーム音を放音する。 5 and 6 show an example in which the piezoelectric buzzer sounding device of the above embodiment is built into a portable electronic watch. FIG. 5 is an external view showing the front side, and FIG. 6 is an external view showing the back side. In FIG. 5, a display section 32, operation keys 33, and a first sound emitting hole 34 are provided on the top surface of a case 31 of a portable electronic watch. The display 32 is made of, for example, a liquid crystal display element, and displays the time. Further, the operation key 33 is used to set the time and the like. Furthermore, the first sound emitting hole 34 is driven by the piezoelectric buzzer sounding device (not shown) built into the case, which is driven and controlled by a clock circuit (not shown) built in, and emits an alarm sound at alarm time, etc. emit a sound.
次に第６図において、ケース３１の裏面上には
第２の放音孔３５およびスタンド部３６が設けら
れている。上記第２の放音孔３５は第１の放音孔
３４と同一機能を有する。またスタンド部３６は
図示するように、ケース３１の裏面の一部を矩形
状に切欠いた凹入部３７と、この凹入部３７内に
基端を支持されて回動し、且つＵ字状に形成され
た合成樹脂のスタンド部材３８とから構成され
る。このスタンド部材３８は全体が弾性を有し、
ケースとは別体である。スタンド部材３８の外側
部両側には１個ずつ外側に突出形成された半球形
状の係止ボス３９が設けられ、またこの係止ボス
３９を受け入れる受け孔（図示略）が凹入部３７
内に形成されている。またスタンド部材３８の基
端にはスタンド部材３８を回動させる軸支ピン４
０が一体に形成されている。そして、凹入部３７
内には軸支ピン４０を支持する軸受（図示略）が
設けられている。したがつて、上述の如くケース
３１とは別体に形成されたスタンド部材３８をケ
ース３１に取付ける際には、スタンド部材３８の
Ｕ字部分を指でつぼめながら軸支ピン４０を凹入
部３７内の軸受に挿入する。そして、指を離せば
スタンド部材３８は全体が弾性的に拡がるので、
軸支ピン４０は確実に軸支される。スタンド部３
６を使用するときは、スタンド部材３８を第６図
のように立てる。このようにすると、係止ボス３
９が凹入部３７の口縁に係止されてスタンド部材
３８は支持される。スタンド部材３８を凹入部３
７に収納するときは、凹入部３７側へ回動させ
る。これにより、係止ボス３９の作用によりスタ
ンド部材３８が全体的に弾性変形し係止ボス３９
は凹入部３７の口縁をのりこえて受け孔内に入
る。 Next, in FIG. 6, a second sound emitting hole 35 and a stand section 36 are provided on the back surface of the case 31. The second sound emitting hole 35 has the same function as the first sound emitting hole 34. Further, as shown in the figure, the stand part 36 has a recessed part 37 formed by cutting out a part of the back surface of the case 31 into a rectangular shape, and has a proximal end supported in the recessed part 37 to rotate, and is formed in a U-shape. The stand member 38 is made of synthetic resin. This stand member 38 has elasticity as a whole,
It is separate from the case. A hemispherical locking boss 39 is provided on each side of the outer side of the stand member 38 and protrudes outward, and a receiving hole (not shown) for receiving the locking boss 39 is provided in the recessed portion 37.
formed within. Also, at the base end of the stand member 38 is a pivot pin 4 for rotating the stand member 38.
0 is integrally formed. And the recessed part 37
A bearing (not shown) that supports the pivot pin 40 is provided inside. Therefore, when attaching the stand member 38, which is formed separately from the case 31 as described above, to the case 31, insert the pivot pin 40 into the recessed part 37 while squeezing the U-shaped part of the stand member 38 with your fingers. Insert into the bearing. Then, when you release your finger, the entire stand member 38 expands elastically.
The pivot pin 40 is reliably pivoted. Stand part 3
6, stand the stand member 38 up as shown in FIG. In this way, the locking boss 3
9 is engaged with the edge of the recessed portion 37, and the stand member 38 is supported. The stand member 38 is inserted into the recessed part 3
7, rotate it toward the recess 37 side. As a result, the stand member 38 is elastically deformed as a whole by the action of the locking boss 39, and the locking boss 39
passes over the edge of the recessed portion 37 and enters the receiving hole.
なお、上記実施例では各周波数B，1，2の関
係をB＜2＜1としたが、B＜1＜2あるいは
1
＜2＜Bでも同様である。また上述した設計例の
各寸法にこの考案が限定されないことは勿論であ
る。さらに実施例では放音孔の形状を円形とした
が、これは他の形状であつてもよい。また圧電ブ
ザー発音装置の全体形状は上述した円形に限ら
ず、他の形状であつてもよい。また携帯用電子時
計のみならず、他の小型電子機器に対してもこの
圧電ブザー発音装置を利用可能である。 In addition, in the above embodiment, the relationship between the frequencies B , 1 , and 2 was set as B < 2 < 1 , but B < 1 < 2 or
1
The same holds true for < 2 < B. Moreover, it goes without saying that this invention is not limited to the dimensions of the design example described above. Further, in the embodiment, the shape of the sound emitting hole is circular, but it may have another shape. Further, the overall shape of the piezoelectric buzzer sounding device is not limited to the circular shape described above, but may be other shapes. Furthermore, this piezoelectric buzzer sounding device can be used not only for portable electronic watches but also for other small electronic devices.
また、携帯用電子時計などにおいてアラーム音
を２つの周波数A，Bで報音する場合、第１およ
び第２の共鳴器の共鳴周波数1，2がA，Bと一
致するように設定すれば、アラーム音を最大の音
圧レベルで報音させることができる。 In addition, when alarm sounds are sounded at two frequencies A and B in a portable electronic watch, etc., if the resonance frequencies 1 and 2 of the first and second resonators are set to match A and B , It is possible to make the alarm sound sound at the maximum sound pressure level.
この考案は以上説明したように、圧電ブザーの
上下面側に対して各々共鳴器を設け、圧電ブザー
の共振周波数と一方の共鳴器の共鳴周波数との間
に他方の共鳴器の共鳴周波数を設定するようにし
たから、音圧レベル−周波数特性がフラツトに近
づいて安定し、音圧レベルが全体として大幅に向
上した圧電ブザー発音装置を提供できる。 As explained above, in this invention, resonators are provided on the upper and lower surfaces of the piezoelectric buzzer, and the resonant frequency of the other resonator is set between the resonant frequency of the piezoelectric buzzer and the resonant frequency of one resonator. By doing so, it is possible to provide a piezoelectric buzzer sounding device in which the sound pressure level-frequency characteristics become nearly flat and stable, and the sound pressure level as a whole is significantly improved.
第１図は従来の圧電ブザー発音装置の縦断側面
図、第２図はこの考案の一実施例における圧電ブ
ザー発音装置の縦断側面図、第３図は従来の圧電
ブザー発音装置の音圧レベル−周波数特性図、第
４図は上記実施例の圧電ブザー発音装置の音圧レ
ベル−周波数特性図、第５図はこの考案を適用し
た携帯用電子時計を表面側から見た外観図、第６
図は同じく携帯用電子時計を裏面側から見た外観
図である。
１１……振動板、１２……圧電素子、１３……
圧電ブザー、１４……共鳴箱、１５……第１の共
鳴器、１６……第２の共鳴器、１７，１９……共
鳴空間、１８，２０……放音孔、３６……スタン
ド部、３７……凹入部、３８……スタンド部材、
３９……係止ボス、４０……軸支ピン。
Fig. 1 is a longitudinal side view of a conventional piezoelectric buzzer sounding device, Fig. 2 is a longitudinal side view of a piezoelectric buzzer sounding device according to an embodiment of this invention, and Fig. 3 is a sound pressure level of a conventional piezoelectric buzzer sounding device. FIG. 4 is a sound pressure level-frequency characteristic diagram of the piezoelectric buzzer sounding device of the above embodiment. FIG. 5 is an external view of a portable electronic watch to which this invention is applied, as seen from the front side.
The figure is also an external view of the portable electronic watch seen from the back side. 11... Vibration plate, 12... Piezoelectric element, 13...
Piezoelectric buzzer, 14... Resonance box, 15... First resonator, 16... Second resonator, 17, 19... Resonance space, 18, 20... Sound emission hole, 36... Stand part, 37... recessed part, 38... stand member,
39... Locking boss, 40... Pivoting pin.
Claims (1)
と、この圧電ブザーの一側面側に設けられた第１
の共鳴器と、上記圧電ブザーの他側面側に設けら
れた第２の共鳴器とを具備し、上記圧電ブザーの
共振周波数と上記第１の共鳴器の共鳴周波数との
間に上記第２の共鳴器の共鳴周波数を設定したこ
とを特徴とする圧電ブザー発音装置。 A piezoelectric buzzer in which a piezoelectric element is stacked and bonded to a diaphragm, and a first one provided on one side of the piezoelectric buzzer.
and a second resonator provided on the other side of the piezoelectric buzzer, wherein the second resonator is provided between the resonant frequency of the piezoelectric buzzer and the resonant frequency of the first resonator. A piezoelectric buzzer sounding device characterized by setting the resonance frequency of a resonator.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16303281U JPS5867399U (en) | 1981-10-30 | 1981-10-30 | Piezoelectric buzzer sound device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16303281U JPS5867399U (en) | 1981-10-30 | 1981-10-30 | Piezoelectric buzzer sound device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5867399U JPS5867399U (en) | 1983-05-07 |
| JPS6312399Y2 true JPS6312399Y2 (en) | 1988-04-08 |
Family
ID=29955335
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16303281U Granted JPS5867399U (en) | 1981-10-30 | 1981-10-30 | Piezoelectric buzzer sound device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5867399U (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59226394A (en) * | 1983-06-07 | 1984-12-19 | ティーディーケイ株式会社 | Acoustic converter |
-
1981
- 1981-10-30 JP JP16303281U patent/JPS5867399U/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5867399U (en) | 1983-05-07 |
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