JPH0375000A - Piezoelectric receiver circuit - Google Patents
Piezoelectric receiver circuitInfo
- Publication number
- JPH0375000A JPH0375000A JP21006789A JP21006789A JPH0375000A JP H0375000 A JPH0375000 A JP H0375000A JP 21006789 A JP21006789 A JP 21006789A JP 21006789 A JP21006789 A JP 21006789A JP H0375000 A JPH0375000 A JP H0375000A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic field
- generating coil
- field generating
- current
- audio signal
- 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
- 239000003990 capacitor Substances 0.000 claims abstract description 18
- 230000005236 sound signal Effects 0.000 claims description 25
- 239000000919 ceramic Substances 0.000 claims description 2
- 230000007423 decrease Effects 0.000 claims description 2
- 238000010586 diagram Methods 0.000 description 10
- 239000000463 material Substances 0.000 description 3
- 239000002131 composite material Substances 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
Landscapes
- Circuit For Audible Band Transducer (AREA)
Abstract
Description
【発明の詳細な説明】
（１）発明の属する産業上の利用分野
本発明は磁界発生コイルが接続された圧電形受話器回路
に関するものである。DETAILED DESCRIPTION OF THE INVENTION (1) Industrial field of application to which the invention pertains The present invention relates to a piezoelectric receiver circuit to which a magnetic field generating coil is connected.
（２）従来の技術とその問題点
第１図は磁界発生コイルを直列に圧電形受話器に接続し
、増幅器で駆動している回路図である。(2) Prior art and its problems FIG. 1 is a circuit diagram in which a magnetic field generating coil is connected in series to a piezoelectric receiver and is driven by an amplifier.
ここで、１は磁界発生コイル、２は圧電形受話器で、例
えばセラミック圧電体、高分子圧電体、複合圧電体を用
いたものが含まれる。３は音声信号増幅器である。Here, 1 is a magnetic field generating coil, and 2 is a piezoelectric receiver, which includes, for example, those using a ceramic piezoelectric material, a polymer piezoelectric material, and a composite piezoelectric material. 3 is an audio signal amplifier.
通常、磁界発生コイル１のインピーダンスは圧電形受話
器２のインピーダンスに比べて小さく、圧電形受話器２
のインピーダンスは容量性であるから、第２図に示すよ
うに磁界発生コイル１と圧電形受話器２の総合インピー
ダンスは周波数に比例して小さくなる。Normally, the impedance of the magnetic field generating coil 1 is smaller than the impedance of the piezoelectric receiver 2, and
Since the impedance of is capacitive, the total impedance of the magnetic field generating coil 1 and the piezoelectric receiver 2 decreases in proportion to the frequency, as shown in FIG.
このため音声信号増幅器３の出力端Ｒ、Ｒｚの出力電圧
が周波数に対して一定である場合、第３図に示すように
磁界発生コイル１に流れる音声信号電流は周波数に比例
して大きくなる。Therefore, when the output voltages of the output terminals R and Rz of the audio signal amplifier 3 are constant with respect to frequency, the audio signal current flowing through the magnetic field generating coil 1 increases in proportion to the frequency as shown in FIG.
磁界発生コイル１から発生する磁界の強度は、磁界発生
コイル１に流れる電流に比例するから、第３図に示すよ
うに磁界強度は周波数に比例して大きくなる。Since the strength of the magnetic field generated from the magnetic field generating coil 1 is proportional to the current flowing through the magnetic field generating coil 1, the magnetic field strength increases in proportion to the frequency as shown in FIG.
磁界強度の周波数特性は平坦である事が要求されるため
、この場合磁界強度の周波数特性は高域上がりとなり要
求を満足しない。Since the frequency characteristic of the magnetic field strength is required to be flat, in this case the frequency characteristic of the magnetic field strength increases in the high range and does not satisfy the requirement.
（３）発明の目的
本発明は、圧電形受話器に固有の容量性インピーダンス
による欠点を解決して、磁界強度の周波数特性を平坦に
した圧電形受話器回路を提供するものである。(3) Object of the Invention The present invention provides a piezoelectric receiver circuit that solves the drawbacks due to capacitive impedance inherent in piezoelectric receivers and flattens the frequency characteristics of magnetic field strength.
（４）発明の構成および作用
この目的達成のために、本発明の圧電形受話器回路は、
磁界発生コイルに並列にコンデンサを接続するか、又は
圧電形受話器に並列もしくは直列に抵抗を接続する構成
を有している。(4) Structure and operation of the invention To achieve this objective, the piezoelectric receiver circuit of the present invention has the following features:
It has a configuration in which a capacitor is connected in parallel to the magnetic field generating coil, or a resistor is connected in parallel or in series to the piezoelectric receiver.
以下本発明の詳細な説明する。The present invention will be explained in detail below.
（実施例１）
第４図は本発明の一実施例であって、４は磁界発生コイ
ル１に並列に接続されたコンデンサである。音声信号電
流ｉは磁界発生コイル１に電流ｉ。(Embodiment 1) FIG. 4 shows an embodiment of the present invention, in which 4 is a capacitor connected in parallel to the magnetic field generating coil 1. In FIG. The audio signal current i is the current i in the magnetic field generating coil 1.
で、コンデンサ４に電ｍ３ａで分流し、コンデンサ４の
インピーダンスが高い周波数において小さくなるから、
第５図に示すように磁界発生コイル１に流れる電流ｉｌ
は曲線４ｂのように高い周波数においてコンデンサ４が
接続されてない場合の曲線４ａに比べて少なくなる。磁
界発生コイル１のインピータンス、圧電形受話器２のイ
ンピーダンスに対して、コンデンサ４のインピーダンス
を適当に選ぶことにより、磁界発生コイルｌに流れる電
流１１を音声周波数帯域においてほぼ一定にすることが
でき、電流ｉｌに比例する磁界強度の周波数特性を平坦
にすることができる。Then, current m3a is shunted to capacitor 4, and the impedance of capacitor 4 becomes small at high frequencies, so
As shown in FIG. 5, the current il flowing through the magnetic field generating coil 1
is smaller at high frequencies as shown in curve 4b compared to curve 4a when capacitor 4 is not connected. By appropriately selecting the impedance of the capacitor 4 with respect to the impedance of the magnetic field generating coil 1 and the impedance of the piezoelectric receiver 2, the current 11 flowing through the magnetic field generating coil 1 can be made almost constant in the audio frequency band, The frequency characteristic of the magnetic field strength, which is proportional to the current il, can be flattened.
−例として、磁界発生コイル１のインピーダンス（直流
抵抗）が１００Ω、圧電形受話器２の容量が０．０５５
μＦ、並列コンデンサ４の容量が４．７μＦの時、第５
図に示すように磁界発生コイル１に流れる電ｉｌが曲線
４ｂのようになる。- As an example, the impedance (DC resistance) of the magnetic field generating coil 1 is 100Ω, and the capacity of the piezoelectric receiver 2 is 0.055.
μF, when the capacitance of parallel capacitor 4 is 4.7 μF, the fifth
As shown in the figure, the electric current flowing through the magnetic field generating coil 1 becomes like a curve 4b.
（実施例２）
第６図は本発明の第２の実施例であって、５は圧電形受
話器２に並列に接続された抵抗である。(Embodiment 2) FIG. 6 shows a second embodiment of the present invention, in which 5 is a resistor connected in parallel to the piezoelectric receiver 2. In FIG.
音声信号電流ｉは圧電形受話器２に電流ｉｔで、抵抗５
に電流ｉｌで分流し、低い周波数において圧電形受話器
２のインピーダンスが大きくなって電流１２が小さくな
るが、抵抗５のインピーダンスは周波数によらず一定だ
から、電流ｉｌは一定に流れる。The audio signal current i is current it to the piezoelectric receiver 2, and the resistance 5
At low frequencies, the impedance of the piezoelectric receiver 2 becomes large and the current 12 becomes small. However, since the impedance of the resistor 5 is constant regardless of the frequency, the current il flows constantly.
この場合には、第７図の曲線５ａに示すように磁界発生
コイル１に流れる電流１１は抵抗５がある場合には低い
周波数において抵抗５が接続されてない場合（同曲線５
ｂ）に比べて大きくなる。磁界発生コイルｌのインピー
ダンス、圧電形受話器２のインピーダンスに対して抵抗
５のインピーダンスを適当に選ぶことにより、磁界発生
コイル１に流れる電流ｉｌを音声周波数帯域においてほ
ぼ一定にすることができ、電流１１に比例する磁界強度
の周波数特性を平坦にすることができる。In this case, as shown by the curve 5a in FIG. 7, the current 11 flowing through the magnetic field generating coil 1 changes when the resistor 5 is present, and when the resistor 5 is not connected at low frequencies (the curve 5a).
It becomes larger compared to b). By appropriately selecting the impedance of the resistor 5 with respect to the impedance of the magnetic field generating coil 1 and the impedance of the piezoelectric receiver 2, the current il flowing through the magnetic field generating coil 1 can be made almost constant in the audio frequency band, and the current 11 The frequency characteristic of the magnetic field strength, which is proportional to , can be made flat.
−例として、磁界発生コイル１のインピーダンス（直流
抵抗）が１００Ω、圧電形受話器２の容量が０．０５５
μＦ、並列抵抗５の抵抗が１にΩの時、第７図に示すよ
うに磁界発生コイルｌに流れる電ｉ。- As an example, the impedance (DC resistance) of the magnetic field generating coil 1 is 100Ω, and the capacity of the piezoelectric receiver 2 is 0.055.
When the resistance of the parallel resistor 5 is μF and the resistance of the parallel resistor 5 is 1 to Ω, the electric current i flowing through the magnetic field generating coil l as shown in FIG.
が曲線５ａのようになる。becomes like curve 5a.
（実施例３）
第８図は本発明の第３の実施例であって、６は磁界発生
コイル１及び圧電形受話器２に直列に接続された抵抗で
ある。音声信号電流ｉは抵抗６の抵抗電流ｌｈｔ磁界発
生コイル電流ｆｌ＋圧電形受話器１２となって流れる。(Third Embodiment) FIG. 8 shows a third embodiment of the present invention, in which 6 is a resistor connected in series to the magnetic field generating coil 1 and the piezoelectric receiver 2. The audio signal current i flows as the resistance current lh of the resistor 6, the magnetic field generating coil current fl+the piezoelectric receiver 12.
この場合には、第９図の曲線６ａに示すように高い周波
数において圧電形受話器２のインピーダンスが小さくな
って音声信号電流ｉが大きくなる所を抵抗６のインピー
ダンスが周波数によらず一定だから、同図曲線６ｂのよ
うに音声信号電流ｉは大きくならない。磁界発生コイル
１に流れる電流ｉ。In this case, as shown by the curve 6a in FIG. 9, the impedance of the piezoelectric receiver 2 becomes small at high frequencies and the audio signal current i becomes large, since the impedance of the resistor 6 is constant regardless of the frequency. The audio signal current i does not increase as shown by curve 6b in the figure. Current i flowing through the magnetic field generating coil 1.
は、高い周波数において抵抗６が直列に接続されていな
い場合に比べて小さくなる。is smaller at high frequencies than when the resistor 6 is not connected in series.
磁界発生コイル１のインピーダンス、圧電形受話器２の
インピーダンスに対して抵抗６のインピーダンスを適当
に選ぶことにより、磁界発生コイルに流れる電流ｉｌを
音声周波数帯域においてほぼ一定にすることができ、電
流ｉｌに比例する磁界強度の周波数特性を平坦にするこ
とができる。By appropriately selecting the impedance of the resistor 6 with respect to the impedance of the magnetic field generating coil 1 and the impedance of the piezoelectric receiver 2, the current il flowing through the magnetic field generating coil can be made almost constant in the audio frequency band, and the current il The frequency characteristics of the proportional magnetic field strength can be flattened.
−例として、磁界発生コイル１のインピーダンス（直流
抵抗）が１００Ω、圧電形受話器２の容量が０．０５５
μＦ、直列抵抗６の抵抗がＩＯＫΩの時、第９図に示す
ように磁界発生コイル１に流れる電ｉＩが曲線６ｂのよ
うになる。- As an example, the impedance (DC resistance) of the magnetic field generating coil 1 is 100Ω, and the capacity of the piezoelectric receiver 2 is 0.055.
When the resistance of the series resistor 6 is μF and the resistance of the series resistor 6 is IOKΩ, the electric current iI flowing through the magnetic field generating coil 1 becomes like a curve 6b, as shown in FIG.
なお、本発明を例えば電話機用の圧電形受話器回路とし
て構成する場合、電話機本体またはハンドセットに実装
する形式としては次のような組合わせが可能である。When the present invention is configured as a piezoelectric receiver circuit for a telephone, for example, the following combinations are possible as mounting formats on the telephone main body or handset.
■ 電話機本体に音声信号増幅器３を実装し、ハンドセ
ット内に磁界発生コイル１と圧電形受話器２を実装して
圧電形受話器回路を構成する形式。■ A type in which an audio signal amplifier 3 is mounted on the telephone body, and a magnetic field generating coil 1 and a piezoelectric receiver 2 are mounted inside the handset to form a piezoelectric receiver circuit.
■ 電話機本体に音声信号増幅器３と磁界発生コイル１
を実装し、ハンドセット内に圧電形受話器２を実装して
圧電形受話器回路を構成する形式。■ Audio signal amplifier 3 and magnetic field generating coil 1 are included in the phone body.
, and a piezoelectric receiver 2 is mounted inside the handset to form a piezoelectric receiver circuit.
■ ハンドセット内に音声信号増幅器３と磁界発生コイ
ルｌおよび圧電形受話器２を一体に実装して圧電形受話
器回路を構成する形式。■ A type in which the audio signal amplifier 3, the magnetic field generating coil 1, and the piezoelectric receiver 2 are integrated into the handset to form a piezoelectric receiver circuit.
■ 電話機本体に音声信号増幅器３を実装し、圧電形受
話器２内に磁界発生コイル１を一体的に、組み込んだも
のをハンドセット内に収容して圧電形受話器回路を構成
する形式。■ A type in which the audio signal amplifier 3 is mounted on the telephone body, and the magnetic field generating coil 1 is integrated into the piezoelectric receiver 2, which is housed in the handset to form a piezoelectric receiver circuit.
■ 圧電形受話器２内に音声信号増幅器３と磁界発生コ
イルｌを一体的に組み込み、それをハンドセットに収容
して圧電形受話器回路を構成する形式。■ A type in which an audio signal amplifier 3 and a magnetic field generating coil 1 are integrated into a piezoelectric receiver 2, and the piezoelectric receiver circuit is configured by housing them in a handset.
これらのいずれの実装形式を採用しても本発明に含まれ
ることは云うまでもない。Needless to say, any of these implementation formats are included in the present invention.
また本発明は電話機用に限定されるものではなく、音響
変換器として各分野に利用することができる。Further, the present invention is not limited to use in telephones, but can be used in various fields as an acoustic transducer.
（５）発明の詳細
な説明したように、本発明によれば、磁界発生コイルよ
り発生する磁界強度の周波数特性を平坦にすることがで
き、圧電形受話器回路に対する要求を満足することがで
きる。(5) As described in detail, according to the present invention, the frequency characteristics of the magnetic field intensity generated by the magnetic field generating coil can be flattened, and the requirements for a piezoelectric receiver circuit can be satisfied.
第１図は磁界発生コイルと圧電形受話器を直列に接続し
音声信号増幅器に接続した回路図、第２図は磁界発生コ
イル、圧電形受話器を合わせた総合インピーダンスの周
波数特性図、第３図は第１図における磁界発生コイルに
流れる電流と磁界発生コイルより発生する磁界強度の周
波数特性図、第４図は第１図に追加して磁界発生コイル
に並列にコンデンサを接続した本発明の一実施例を示す
回路図、第５図は第４図においてコンデンサを接続した
場合としない場合の磁界発生コイルに流れる電流の周波
数特性図、第６図は本発明の第２の実施例を示す回路図
、第７図は第６図において抵抗を接続した場合としない
場合の磁界発生コイルに流れる電流の周波数特性図、第
８図は第１図に追加して磁界発生コイルと圧電形受話器
に直列に抵抗を接続した本発明の第３の実施例を示す回
路図、第９図は第８図において抵抗を接続した場合とし
ない場合の磁界発生コイルに流れる電流の周波数特性図
である。
ｌ・・・磁界発生コイル、 ２・・・圧電形受話器、３
・・・音声信号増幅器、 ｉ・・・全体に流れる音声
信号電流、 ｉ＋・・・磁界発生コイルに流れる電流
、 ｉ、・・・圧電形受話器に流れる電流、ｉ４・・
・コンデンサ４に流れる電流、 ４・・・磁界発生コイ
ルｌに並列に接続されたコンデンサ、５・・・圧電形受
話器２に並列に接続された抵抗、ｉ、・・・抵抗に流れ
る電流、 ６・・・磁界発生コイルｌ及び圧電形受話器
２に直列に接続された抵抗、 ｉ、・・・抵抗６に流
れる電流。
第１図
第２図Figure 1 is a circuit diagram in which a magnetic field generating coil and a piezoelectric receiver are connected in series and connected to an audio signal amplifier. Figure 2 is a frequency characteristic diagram of the total impedance of the magnetic field generator coil and piezoelectric receiver. Fig. 1 is a frequency characteristic diagram of the current flowing through the magnetic field generating coil and the magnetic field intensity generated by the magnetic field generating coil, and Fig. 4 is an embodiment of the present invention in which a capacitor is connected in parallel to the magnetic field generating coil in addition to Fig. 1. A circuit diagram showing an example, FIG. 5 is a frequency characteristic diagram of the current flowing through the magnetic field generating coil with and without a capacitor connected in FIG. 4, and FIG. 6 is a circuit diagram showing a second embodiment of the present invention. , Figure 7 is a frequency characteristic diagram of the current flowing through the magnetic field generating coil with and without a resistor connected in Figure 6, and Figure 8 is an addition to Figure 1 that shows the frequency characteristics of the current flowing in the magnetic field generating coil and the piezoelectric receiver in series. FIG. 9 is a circuit diagram showing a third embodiment of the present invention in which a resistor is connected. FIG. 9 is a frequency characteristic diagram of the current flowing through the magnetic field generating coil when a resistor is connected and not in FIG. 8. l...Magnetic field generating coil, 2...Piezoelectric receiver, 3
...Audio signal amplifier, i...Audio signal current flowing throughout, i+...Current flowing in the magnetic field generating coil, i,...Current flowing in the piezoelectric receiver, i4...
・Current flowing through capacitor 4, 4... Capacitor connected in parallel to magnetic field generating coil l, 5... Resistor connected in parallel to piezoelectric receiver 2, i... Current flowing through resistor, 6 . . . A resistor connected in series to the magnetic field generating coil l and the piezoelectric receiver 2, i, . . . A current flowing through the resistor 6. Figure 1 Figure 2
Claims (3)
形受話器に直列に磁界発生コイルが接続された圧電形受
話器回路において、 前記磁界発生コイルに並列にコンデンサが接続され、音
声周波数の低域で音声信号電流が増加するのを該コンデ
ンサに分流させて、前記磁界発生コイルには音声周波数
の低域から高域までほぼ一定の音声信号電流が流れるよ
うに構成されたことを特徴とするセラミック受話器回路
。(1) In a piezoelectric handset circuit in which a magnetic field generating coil is connected in series to a piezoelectric handset in order to generate a magnetic field corresponding to an audio signal, a capacitor is connected in parallel to the magnetic field generating coil to generate a magnetic field corresponding to a low audio frequency. The present invention is characterized in that an increase in the audio signal current in the audio frequency range is shunted to the capacitor, so that a substantially constant audio signal current flows through the magnetic field generating coil from the low frequency range to the high audio frequency range. Ceramic handset circuit.
形受話器に直列に磁界発生コイルが接続された圧電形受
話器回路において、 前記圧電形受話器に並列に抵抗が接続され、音声周波数
の低域で音声信号電流が減少するのを該抵抗に分流させ
て、前記磁界発生コイルには音声周波数の低域から高域
までほぼ一定の音声信号電流が流れるように構成された
ことを特徴とする圧電形受話器回路。(2) In a piezoelectric handset circuit in which a magnetic field generating coil is connected in series to a piezoelectric handset in order to generate a magnetic field according to an audio signal, a resistor is connected in parallel to the piezoelectric handset to generate a magnetic field corresponding to a low audio frequency. The present invention is characterized in that the audio signal current decreases in the audio frequency range by shunting the audio signal current to the resistor so that a substantially constant audio signal current flows through the magnetic field generating coil from the low audio frequency range to the high audio frequency range. Piezoelectric receiver circuit.
形受話器に直列に磁界発生コイルが接続された圧電形受
話器回路において、 前記圧電形受話器及び前記磁界発生コイルに直列に抵抗
が接続され、総合インピーダンスが音声周波数の低域か
ら高域までほぼ一定にして磁界発生コイルに音声周波数
帯域においてほぼ一定の音声信号電流が流れるように構
成されたことを特徴とする圧電形受話器回路。(3) In a piezoelectric handset circuit in which a magnetic field generating coil is connected in series to a piezoelectric handset in order to generate a magnetic field according to an audio signal, a resistor is connected in series to the piezoelectric handset and the magnetic field generating coil. A piezoelectric receiver circuit characterized in that the overall impedance is substantially constant from low to high audio frequencies, so that a substantially constant audio signal current flows through the magnetic field generating coil in the audio frequency band.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21006789A JP2775479B2 (en) | 1989-08-16 | 1989-08-16 | Piezoelectric receiver circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21006789A JP2775479B2 (en) | 1989-08-16 | 1989-08-16 | Piezoelectric receiver circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0375000A true JPH0375000A (en) | 1991-03-29 |
| JP2775479B2 JP2775479B2 (en) | 1998-07-16 |
Family
ID=16583274
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21006789A Expired - Fee Related JP2775479B2 (en) | 1989-08-16 | 1989-08-16 | Piezoelectric receiver circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2775479B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2011125544A1 (en) * | 2010-04-09 | 2011-10-13 | オリンパスメディカルシステムズ株式会社 | Ultrasonic surgery system and surgical treatment tool |
-
1989
- 1989-08-16 JP JP21006789A patent/JP2775479B2/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2011125544A1 (en) * | 2010-04-09 | 2011-10-13 | オリンパスメディカルシステムズ株式会社 | Ultrasonic surgery system and surgical treatment tool |
| JP4889832B2 (en) * | 2010-04-09 | 2012-03-07 | オリンパスメディカルシステムズ株式会社 | Ultrasonic surgical system and surgical treatment instrument |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2775479B2 (en) | 1998-07-16 |
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