JPH06338641A - Piezoelectric ceramic transformer and drive thereof - Google Patents
Piezoelectric ceramic transformer and drive thereofInfo
- Publication number
- JPH06338641A JPH06338641A JP5126837A JP12683793A JPH06338641A JP H06338641 A JPH06338641 A JP H06338641A JP 5126837 A JP5126837 A JP 5126837A JP 12683793 A JP12683793 A JP 12683793A JP H06338641 A JPH06338641 A JP H06338641A
- Authority
- JP
- Japan
- Prior art keywords
- piezoelectric ceramic
- voltage
- plate
- ceramic plate
- electrodes
- 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.)
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Classifications
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- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N30/00—Piezoelectric or electrostrictive devices
- H10N30/40—Piezoelectric or electrostrictive devices with electrical input and electrical output, e.g. functioning as transformers
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、高周波帯で動作可能な
圧電磁器トランス、特に小型化，薄型化が要求されるオ
ンボード用圧電磁器トランス及びその駆動方法に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric ceramic transformer capable of operating in a high frequency band, and more particularly to an onboard piezoelectric ceramic transformer which is required to be small and thin and a driving method thereof.
【０００２】[0002]
【従来の技術】近年、電子装置の電源回路を小型にする
ために、スイッチング電源のスイッチング周波数の高周
波化が図られている。従来より、このスイッチング電源
には、電磁トランスが用いられており、スイッチング電
源の小型化には、周知のようにスイッチング周波数の高
周波化が望ましい。しかしながら、スイッチング周波数
を高くすると、電磁トランスに用いられている磁性材料
のヒステリシス損失，渦電流損失や導線の表皮効果によ
る損失が急激に増大し、トランスの効率が非常に低くな
るという欠点があった。このため、電磁トランスの実用
的な周波数帯域の上限は、せいぜい５００ｋＨｚであっ
た。2. Description of the Related Art In recent years, the switching frequency of a switching power supply has been increased to reduce the size of a power supply circuit of an electronic device. Conventionally, an electromagnetic transformer has been used for this switching power supply, and as is well known, it is desirable to increase the switching frequency to reduce the size of the switching power supply. However, when the switching frequency is increased, the hysteresis loss of the magnetic material used in the electromagnetic transformer, the eddy current loss, and the loss due to the skin effect of the conductor wire sharply increase, resulting in a very low transformer efficiency. . For this reason, the upper limit of the practical frequency band of the electromagnetic transformer was at most 500 kHz.
【０００３】これに対して、圧電磁器トランスは、共振
状態で使用され、一般の電磁トランスに比べて、（１）
同一周波数においてエネルギー密度が高いため、小型化
が図れること，（２）不燃化が図れること，（３）電磁
誘導によるノイズが発生しないこと等、数多くの長所を
有している。On the other hand, the piezoelectric ceramic transformer is used in a resonance state, and compared with a general electromagnetic transformer, (1)
Since the energy density is high at the same frequency, it has many advantages such as downsizing, (2) non-combustibility, and (3) no noise due to electromagnetic induction.
【０００４】図６に従来の代表的な圧電磁器トランスで
あるローゼン型圧電磁器トランスの構造を示す。以下、
図面に沿って説明する。高電圧を取り出す場合、表面に
電極が設けられた圧電磁器板において、６１で示す部分
は圧電磁器トランスの低インピーダンスの駆動部であ
り、その上下面に電極６３，６４が設けられており、駆
動部６１は、図中矢印で示すように厚み方向に分極され
ている。また、同様に６２で示す部分は、高インピーダ
ンスの発電部であり、その端面に電極６５が設けられて
おり、発電部６２は、図中矢印で示すように圧電板の長
さ方向に分極されている。FIG. 6 shows the structure of a Rosen type piezoelectric ceramic transformer which is a typical conventional piezoelectric ceramic transformer. Less than,
It will be described with reference to the drawings. When a high voltage is to be taken out, in the piezoelectric ceramic plate having electrodes provided on the surface, the portion indicated by 61 is a low impedance driving portion of the piezoelectric ceramic transformer, and electrodes 63 and 64 are provided on the upper and lower surfaces thereof to drive the piezoelectric ceramic plate. The portion 61 is polarized in the thickness direction as shown by the arrow in the figure. Similarly, a portion indicated by 62 is a high-impedance power generation portion, and an electrode 65 is provided on the end face thereof, and the power generation portion 62 is polarized in the length direction of the piezoelectric plate as indicated by the arrow in the figure. ing.
【０００５】この圧電磁器トランスの動作は、駆動電極
６３，６４に電圧が印加されると、電気機械結合係数ｋ
31をもって圧電横効果３１モードで長さ縦振動が励振さ
れ、トランス全体が振動する。次に発電部６２では、電
気機械結合係数ｋ33をもって圧電縦効果３３モードによ
り、出力電極６５から高電圧が取り出される。一方、高
電圧を入力させ、低電圧を出力させる場合には、縦効果
の高インピーダンスの発電部６２を入力側とし、横効果
の低インピーダンスの駆動部６１を出力側にすれば良い
ことは、明らかである。他のタイプの圧電磁器トランス
も、いずれもローゼン型と同じ平板の伸び振動や、円板
の半径方向拡がり振動を利用したものであり、適用周波
数は、最高２００ｋＨｚ程度までである。The operation of this piezoelectric ceramic transformer is such that when a voltage is applied to the drive electrodes 63 and 64, the electromechanical coupling coefficient k.
With 31 , the longitudinal piezoelectric vibration is excited in the piezoelectric transverse effect 31 mode, and the entire transformer vibrates. Next, in the power generation section 62, a high voltage is taken out from the output electrode 65 in the piezoelectric vertical effect 33 mode with the electromechanical coupling coefficient k 33 . On the other hand, in the case of inputting a high voltage and outputting a low voltage, it suffices to set the vertical effect high impedance power generation unit 62 on the input side and the horizontal effect low impedance drive unit 61 on the output side. it is obvious. The other types of piezoelectric ceramic transformers also utilize the same flat plate vibration as the Rosen type and the radial vibration of the circular plate, and the applicable frequency is up to about 200 kHz.
【０００６】[0006]
【発明が解決しようとする課題】以上の従来例で示した
ように、圧電磁器トランスの適用周波数領域は、２００
ｋＨｚ以下の低周波領域においてのみであった。また、
ローゼン型の圧電磁器トランスは、縦効果の電気機械結
合係数に比べて著しく小さい横効果縦振動モードの電気
機械結合係数ｋ31を用いざるを得ないため、帯域幅が小
さいという欠点があった。As shown in the above conventional example, the applicable frequency range of the piezoelectric ceramic transformer is 200
Only in the low frequency region below kHz. Also,
The Rosen type piezoelectric ceramic transformer has a drawback that the bandwidth is small because it is unavoidable to use the electromechanical coupling coefficient k 31 of the lateral effect longitudinal vibration mode which is remarkably smaller than the electromechanical coupling coefficient of the longitudinal effect.
【０００７】本発明の目的は、数百ｋＨｚ〜１ＭＨｚ以
上の高周波帯で使用できる圧電磁器トランス及びその駆
動方法を提供することにある。An object of the present invention is to provide a piezoelectric ceramic transformer which can be used in a high frequency band of several hundred kHz to 1 MHz or more and a driving method thereof.
【０００８】[0008]
【課題を解決するための手段】前記目的を達成するた
め、本発明に係る圧電磁器トランスは、圧電磁器板と、
電極の対と、外部端子の対とを有する圧電磁器トランス
であって、圧電磁器板は、板状の圧電振動体であって、
板厚方向に一様に分極され、幅方向縦振動モードの共振
周波数近傍の周波数の交流電圧を入力として励振し、交
流電圧を出力するものであり、対をなす電極は、圧電磁
器板の板厚方向の端面に、対向した位置で、かつ、その
幅方向に該圧電磁器板の励振モードに対応して分割して
設けたものであり、対をなす外部端子の一方は、圧電磁
器板に交流電圧を印加する入力端であり、他方は、圧電
磁器板の電圧をピックアップする出力端であり、該対を
なす外部端子は、圧電磁器板の板厚方向の一端面側で分
割電極を１個おきに電圧の入力側と電圧の出力側とに分
離して接続したものである。To achieve the above object, a piezoelectric ceramic transformer according to the present invention comprises a piezoelectric ceramic plate,
A piezoelectric ceramic transformer having a pair of electrodes and a pair of external terminals, wherein the piezoelectric ceramic plate is a plate-shaped piezoelectric vibrating body,
It is polarized uniformly in the plate thickness direction and is excited by an AC voltage having a frequency near the resonance frequency of the longitudinal vibration mode in the width direction as an input and outputs an AC voltage.The pair of electrodes is a plate of a piezoelectric ceramic plate. The end faces in the thickness direction are provided at positions facing each other and divided in the width direction in accordance with the excitation mode of the piezoelectric ceramic plate, and one of the pair of external terminals is connected to the piezoelectric ceramic plate. The other end is an input end for applying an AC voltage, and the other end is an output end for picking up the voltage of the piezoelectric ceramic plate. The paired external terminals are divided electrodes on one end face side in the plate thickness direction of the piezoelectric ceramic plate. Every other piece is connected separately to the voltage input side and the voltage output side.
【０００９】また、本発明に係る圧電磁器トランスの駆
動方法は、圧電磁器板に幅方向縦振動モードの共振周波
数近傍の周波数の交流電圧を印加し、該圧電磁器板を励
振させて交流電圧を出力させる圧電磁器トランスの駆動
方法であって、圧電磁器板は、板厚方向に一様に分極さ
れた板状の圧電振動体であって、板厚方向の両端面に、
対向した位置で、その幅方向に２以上のｐ個に分割して
設けた対をなす電極を有し、圧電磁器板に交流電圧を印
加する入力用外部端子と、圧電磁器板の電圧をピックア
ップする出力用外部端子とにより、圧電磁器板の板厚方
向の一端面側にてｐ個に分割された電極を１個おきに電
圧の入力側と電圧の出力側とに分離して接続し、さらに
入力側外部端子を電源に接続し、かつ出力側外部端子を
負荷に接続し、前記幅方向縦振動モードを、前記電極が
分割された個数と同数のｐ次モードに設定し、前記圧電
磁器板を励振して駆動するものである。In the method of driving the piezoelectric ceramic transformer according to the present invention, an AC voltage having a frequency near the resonance frequency of the longitudinal vibration mode in the width direction is applied to the piezoelectric ceramic plate and the piezoelectric ceramic plate is excited to generate the AC voltage. A method of driving a piezoelectric ceramic transformer for outputting, wherein the piezoelectric ceramic plate is a plate-shaped piezoelectric vibrating body uniformly polarized in the plate thickness direction.
It has a pair of electrodes divided into two or more p-pieces in the width direction at opposite positions, and has an external input terminal for applying an AC voltage to the piezoelectric ceramic plate and the voltage of the piezoelectric ceramic plate. With the external terminal for output, every other electrode divided into p pieces on one end face side in the plate thickness direction of the piezoelectric ceramic plate is separately connected to the voltage input side and the voltage output side, Further, the input-side external terminal is connected to a power source, and the output-side external terminal is connected to a load, and the widthwise longitudinal vibration mode is set to a p-order mode which is the same number as the number of divided electrodes, and the piezoelectric ceramic The plate is excited and driven.
【００１０】また、本発明に係る圧電磁器トランスは、
圧電磁器板と、電極の対と、外部端子の対とを有する圧
電磁器トランスであって、圧電磁器板は、板状の圧電振
動体であって、板厚方向に分極され、幅方向縦振動モー
ドの共振周波数近傍の周波数の交流電圧を入力として励
振し、交流電圧を出力するものであり、駆動部と発電部
とを有し、駆動部と発電部は、圧電磁器板の幅方向に分
離して配置され、駆動部は、圧電磁器板の幅方向に沿っ
て分割され、かつ、その分極方向が交互に異なる領域か
らなり、発電部は、圧電磁器板の幅方向に沿って分割さ
れ、かつ、その分極方向が交互に異なる領域からなり、
対をなす電極は、圧電磁器板の板厚方向の両端面に、対
向した位置で、かつ、駆動部及び発電部の各分割領域毎
に分割して設けたものであり、対をなす外部端子の一方
は、圧電磁器板に交流電圧を印加する入力端であり、他
方は圧電磁器板の電圧をピックアップする出力端であ
り、該対をなす外部端子は、圧電磁器板の板厚方向の一
端面側で分割電極を駆動部側と発電部側とに分離して接
続したものである。Further, the piezoelectric ceramic transformer according to the present invention is
A piezoelectric ceramic transformer having a piezoelectric ceramic plate, a pair of electrodes, and a pair of external terminals, wherein the piezoelectric ceramic plate is a plate-shaped piezoelectric vibrating body, polarized in the thickness direction, and longitudinally vibrated in the width direction. It excites by inputting an AC voltage having a frequency close to the resonance frequency of the mode and outputs an AC voltage. The driving unit is divided along the width direction of the piezoelectric ceramic plate, and the polarization direction is composed of regions which are alternately different, and the power generation unit is divided along the width direction of the piezoelectric ceramic plate. And, it consists of regions whose polarization directions are alternately different,
The paired electrodes are provided on both end faces in the plate thickness direction of the piezoelectric ceramic plate at positions facing each other and divided for each divided region of the drive unit and the power generation unit. One is an input end for applying an AC voltage to the piezoelectric ceramic plate, and the other is an output end for picking up the voltage of the piezoelectric ceramic plate.The pair of external terminals is one in the plate thickness direction of the piezoelectric ceramic plate. The divided electrodes are separately connected to the drive unit side and the power generation unit side on the end face side.
【００１１】また、本発明に係る圧電磁器トランスの駆
動方法は、圧電磁器板に幅方向縦振動モードの共振周波
数近傍の周波数の交流電圧を印加し、該圧電磁器板を励
振させて交流電圧を出力させる圧電磁器トランスの駆動
方法であって、圧電磁器板は、板厚方向に分極された板
状の圧電振動体であって、圧電磁器板の幅方向に沿って
ｍ個に分割され、かつ、その分極方向が交互に異なる領
域の駆動部と、圧電磁器板の幅方向に沿ってｎ個に分割
され、かつ、その分極方向が交互に異なる領域の発電部
とを有し、駆動部及び発電部の各分割領域は、圧電磁器
板の板厚方向の端面の対向した位置に設けられた対をな
す電極を有し、圧電磁器板に交流電圧を印加する入力側
外部端子と、圧電磁器板の電圧をピックアップする出力
側外部端子とにより、圧電磁器板の板厚方向の一端面側
にてｍ個とｎ個とに分割された電極を駆動部側と発電部
側とに分離して接続し、さらに入力側外部端子を電源に
接続し、かつ出力側外部端子を負荷に接続し、前記幅方
向縦振動モードを、前記電極が分割された（ｍ＋ｎ）個
と同数の（ｍ＋ｎ）次モードに設定し、前記圧電磁器板
を励振して駆動するものである。In the method for driving a piezoelectric ceramic transformer according to the present invention, an alternating voltage having a frequency near the resonance frequency of the longitudinal vibration mode in the width direction is applied to the piezoelectric ceramic plate, and the piezoelectric plate is excited to generate the alternating voltage. A method of driving a piezoelectric ceramic transformer for outputting, wherein the piezoelectric ceramic plate is a plate-shaped piezoelectric vibrating body polarized in the plate thickness direction, and is divided into m pieces along the width direction of the piezoelectric ceramic plate, and A driving section in a region whose polarization directions are different from each other and a power generation section which is divided into n pieces along the width direction of the piezoelectric ceramic plate and whose polarization directions are different from each other. Each divided area of the power generation section has a pair of electrodes provided at opposite positions on the end face of the piezoelectric ceramic plate in the plate thickness direction, and an input side external terminal for applying an AC voltage to the piezoelectric ceramic plate and the piezoelectric ceramic. The output side external terminal for picking up the plate voltage , The electrodes divided into m pieces and n pieces on one end face side in the plate thickness direction of the piezoelectric ceramic plate are separately connected to the drive section side and the power generation section side, and the input side external terminal is connected to the power supply. Then, the output side external terminal is connected to a load, and the widthwise longitudinal vibration mode is set to the (m + n) th order mode, which is the same number as the (m + n) number of divided electrodes, and the piezoelectric ceramic plate is excited. It is driven by.
【００１２】[0012]
【作用】請求項１の圧電磁器トランスの斜視図を図１
（ａ）に、また断面図を図１（ｂ）に示す。ここでは、
例として電極は４個に分割されている。圧電磁器板１１
は、図中矢印で示されるように板厚方向に一様に分極さ
れた板状の圧電振動体である。圧電磁器板１１の上側の
主面上には、４個の電極１２１〜１２４が配置され、下
側の主面上には、４個の電極１３１〜１３４が上側の電
極と対向する位置に配置されている。上側の電極のう
ち、電極１２１と１２３が外部端子１４に接続されてい
る。同様に電極１２２と１２４は外部端子１６に、電極
１３１と１３３は外部端子１５に、電極１３２と１３４
は外部端子１７にそれぞれ接続されている。このように
本発明では、電極は１個おきに同一の外部端子に電気的
に接続されていることが特徴である。尚、ここでは外部
端子を４個取り出しているが、片側の主面上の電極１３
１から１３４を全て接続し、入出力の共通端子とするこ
とにより、３端子トランスとして用いることも可能であ
る。この圧電磁器トランスの外部端子１４〜１５間に、
幅方向縦振動モードの共振周波数近傍の周波数をもつ交
流電圧を印加すれば、電気機械結合係数ｋ31’をもって
圧電磁器板１１が幅縦振動モードで励振され、再び電気
機械結合係数ｋ31’をもって外部端子１６〜１７間に入
力電圧と同じ周波数の電圧が発生する。このとき、出力
電圧は、外部端子１６〜１７間に接続される負荷や駆動
周波数に依存する。A perspective view of the piezoelectric ceramic transformer according to claim 1 is shown in FIG.
A sectional view is shown in FIG. here,
As an example, the electrode is divided into four. Piezoelectric ceramic plate 11
Is a plate-shaped piezoelectric vibrating body uniformly polarized in the plate thickness direction as indicated by an arrow in the figure. Four electrodes 121 to 124 are arranged on the upper main surface of the piezoelectric ceramic plate 11, and four electrodes 131 to 134 are arranged on the lower main surface at positions facing the upper electrodes. Has been done. Of the upper electrodes, the electrodes 121 and 123 are connected to the external terminal 14. Similarly, the electrodes 122 and 124 are used for the external terminal 16, the electrodes 131 and 133 are used for the external terminal 15, and the electrodes 132 and 134 are used.
Are connected to the external terminals 17, respectively. As described above, the present invention is characterized in that every other electrode is electrically connected to the same external terminal. Although four external terminals are taken out here, the electrode 13 on one main surface is
It is also possible to use as a three-terminal transformer by connecting all of 1 to 134 and making them common terminals for input and output. Between the external terminals 14 to 15 of this piezoelectric ceramic transformer,
By applying an alternating voltage with a frequency near the resonance frequency in the width direction longitudinal vibration mode electromechanical coupling factor k 31 'the piezoelectric ceramic plate 11 with it is excited by the width longitudinal vibration mode electromechanical coupling factor k 31 again' with A voltage having the same frequency as the input voltage is generated between the external terminals 16 to 17. At this time, the output voltage depends on the load connected between the external terminals 16 to 17 and the drive frequency.
【００１３】図２には、幅縦振動４次モードの変位と歪
及び電荷の分布を示す。圧電磁器板１１に印加する交流
電圧の周波数の幅方向縦振動モードを４次モードとし、
これに合わせて電極１２１〜１２４，１３１〜１３４を
４個設けてある。変位分布の図から幅縦振動モードを４
次モードとし、電極の個数を４個に設定すると、４個の
電極の中心部が振動の節になっていることが分かり、こ
の振動の節から外部端子を取り出せば、良好な振動特性
を得ることが可能となる。次に歪及び電荷分布に関して
説明する。図２の圧電磁器トランスでは、分極方向が板
厚方向に一様であるため、歪と電荷の分布は一致する。
したがって、電極毎に正と負の電荷が交互に発生する。
本発明の圧電磁器トランスでは、電極は、振動の節に位
置するように、圧電磁器板１１の幅方向に該圧電磁器板
１１の励振モードに対応して設け、電極１２１〜１２
４，１３１〜１３４を１個おきに電圧の入力側と電圧の
出力側とに分離して同一の外部端子にて接続している。
したがって、同一の外部端子に接続された電極には、全
て同符号の電荷しか存在せず、効率良くエネルギーを伝
送させることが可能である。FIG. 2 shows the displacement, strain, and charge distribution of the fourth-longitudinal vibration mode. The widthwise longitudinal vibration mode of the frequency of the AC voltage applied to the piezoelectric ceramic plate 11 is defined as the fourth mode,
In accordance with this, four electrodes 121 to 124 and 131 to 134 are provided. From the diagram of the displacement distribution, 4
When the next mode is set and the number of electrodes is set to 4, it is found that the central part of the four electrodes is a vibration node, and if the external terminal is taken out from this vibration node, good vibration characteristics are obtained. It becomes possible. Next, the strain and charge distribution will be described. In the piezoelectric ceramic transformer of FIG. 2, since the polarization direction is uniform in the plate thickness direction, the strain and the charge distribution match.
Therefore, positive and negative charges are alternately generated for each electrode.
In the piezoelectric ceramic transformer of the present invention, the electrodes are provided in the width direction of the piezoelectric ceramic plate 11 corresponding to the excitation mode of the piezoelectric ceramic plate 11 so as to be positioned at the nodes of vibration, and the electrodes 121 to 12 are provided.
Every other 4,131 to 134 are separated into a voltage input side and a voltage output side and are connected to the same external terminal.
Therefore, the electrodes connected to the same external terminal all have only the charges of the same sign, and it is possible to efficiently transmit energy.
【００１４】次に請求項３で記述した圧電磁器トランス
について説明する。図３（ａ）に斜視図を、また図３
（ｂ）に断面図を示す。図中、圧電磁器板の左半分を駆
動部，右半分を発電部とし、ここでは、例として駆動部
及び発電部のそれぞれを２分割している。駆動部に含ま
れる隣接の領域３１１と３１２では、分極の方向が逆
に、また発電部に含まれる隣接の領域３１３と３１４で
も分極の方向が逆になっていることが、本構造の特徴で
ある。駆動部の同一主面上にある電極３２１と３２２
は、外部端子３４と電気的に接続されている。同様に、
電極３３１と３３２は外部端子３５に、発電部の電極３
２３と３２４は外部端子３６に、電極３３３と３３４は
外部端子３７にそれぞれ接続されている。このような構
造の圧電磁器トランスにおいて、外部端子３４〜３５間
に電圧を印加すると、電気機械結合係数ｋ31’をもって
エネルギーが伝送され、外部端子３６〜３７間に電圧が
発生する。この幅縦振動の電気機械結合係数ｋ31’は一
般に長さ縦振動の電気機械結合係数ｋ31よりも大きいた
め、高電力化・高効率化に有利である。Next, the piezoelectric ceramic transformer described in claim 3 will be described. A perspective view is shown in FIG.
A sectional view is shown in FIG. In the figure, the left half of the piezoelectric ceramic plate is the drive unit, and the right half is the power generation unit. Here, as an example, the drive unit and the power generation unit are each divided into two. The characteristic of this structure is that the directions of polarization are opposite in the adjacent regions 311 and 312 included in the drive unit, and the directions of polarization are also opposite in the adjacent regions 313 and 314 included in the power generation unit. is there. Electrodes 321 and 322 on the same main surface of the driving unit
Are electrically connected to the external terminals 34. Similarly,
The electrodes 331 and 332 are connected to the external terminal 35 and the electrodes 3 of the power generation unit.
23 and 324 are connected to the external terminal 36, and the electrodes 333 and 334 are connected to the external terminal 37, respectively. In the piezoelectric ceramic transformer having such a structure, when a voltage is applied between the external terminals 34 and 35, energy is transmitted with the electromechanical coupling coefficient k 31 ′ and a voltage is generated between the external terminals 36 and 37. Since the electromechanical coupling coefficient k 31 ′ of the longitudinal longitudinal vibration is generally larger than the electromechanical coupling coefficient k 31 of the longitudinal longitudinal vibration, it is advantageous for high power and high efficiency.
【００１５】図４には、幅縦振動４次モードの変位と歪
及び電荷の分布を示す。変位及び歪の分布は、図２と同
じである。駆動部に注目すると、領域３１１と３１２で
は歪の符号が逆になっている。ところが、領域３１１と
３１２では、分極方向も逆になっているため、歪の結果
生じる電荷の符号は、共に正となる。同様に発電部でも
領域３１３と３１４の電荷の符号は、共に負であるの
で、効率良くエネルギーを伝送することが可能となる。FIG. 4 shows the distribution of the displacement, strain, and charge in the fourth-longitudinal vibration mode. The displacement and strain distributions are the same as in FIG. Focusing on the drive unit, the signs of distortion are reversed in the regions 311 and 312. However, in the regions 311 and 312, the polarization directions are also opposite, so that the signs of the charges generated as a result of the strain are both positive. Similarly, in the power generation unit, since the signs of the charges in the regions 313 and 314 are both negative, it is possible to efficiently transfer energy.
【００１６】本発明に係る圧電磁器トランスの共振周波
数近傍の集中定数近似等価回路は、他の圧電トランスと
同様に図５で示される。図５において、Ｃｄ1，Ｃｄ2は
それぞれ入力側，出力側の制動容量，Ａ1，Ａ2は入出力
の力係数，ｍ，ｃ，ｒmは幅縦振動４次モードに関する
等価質量，等価コンプライアンス，等価機械抵抗であ
る。本発明の圧電磁器トランスの入出力の力係数Ａ1，
Ａ2は、幅，長さ，駆動部の電極指間の距離，電極指の
本数で変化する。図５の等価回路から明らかなように、
圧電トランスは、理想変圧器以外に等価インダクタンス
や等価容量を持つので、負荷抵抗の値や駆動周波数によ
って出力電圧が変化する。そのため、Ａ1／Ａ2が１であ
っても、昇圧あるいは降圧どちらのトランスとしても用
いることが可能である。A lumped constant approximate equivalent circuit in the vicinity of the resonance frequency of the piezoelectric ceramic transformer according to the present invention is shown in FIG. 5 like other piezoelectric transformers. In FIG. 5, Cd 1, Cd 2 each input, damping capacity of the output side, A 1, A 2 is the force factor of the input and output, m, c, r m is the equivalent mass in the width longitudinal vibration fourth-order mode, the equivalent Compliance and equivalent mechanical resistance. Input / output force coefficient A 1 of the piezoelectric ceramic transformer of the present invention,
A 2 changes depending on the width, the length, the distance between the electrode fingers of the driving unit, and the number of electrode fingers. As is clear from the equivalent circuit of FIG.
Since the piezoelectric transformer has an equivalent inductance and an equivalent capacitance other than the ideal transformer, the output voltage changes depending on the value of the load resistance and the driving frequency. Therefore, even if A 1 / A 2 is 1, it can be used as either a step-up or step-down transformer.
【００１７】また、本圧電磁器トランスは、図１，図３
及び図５から明らかなように入出力の電気端子は、それ
ぞれ直流的に絶縁された４端子構造とすることが可能で
ある。図６で示した３端子型のローゼン型の圧電トラン
スに比べて周辺回路の自由度を高くすることが可能であ
る。Further, the main piezoelectric ceramic transformer is shown in FIGS.
As is clear from FIG. 5 and FIG. 5, the input and output electric terminals may have a four-terminal structure that is galvanically isolated. It is possible to increase the degree of freedom of the peripheral circuit as compared with the three-terminal type Rosen type piezoelectric transformer shown in FIG.
【００１８】[0018]
【実施例】以下、本発明の実施例について説明する。EXAMPLES Examples of the present invention will be described below.
【００１９】（実施例１）本発明に基づく圧電磁器トラ
ンスの実施例として、図１に示した構成の圧電磁器トラ
ンスを作製した。圧電磁器板１１の材料には、ＰＺＴ
（ＰｂＺｒＯ3−ＰｂＴｉＯ3）系圧電磁器材料を用い
た。まず、焼成された圧電磁器ブロックをダイアモンド
カッターで切断し、＃３０００のＳｉＣ研磨粉を用いて
平行平面に研磨することにより、長さ１０ｍｍ，幅８ｍ
ｍ，厚さ１ｍｍの圧電磁器板を用意する。圧電磁器板上
にＡｇペーストをスクリーン印刷・焼成することによ
り、電極１２１〜１２４，１３１〜１３４を形成した。
これらの外部電極は、塗布・焼成以外の方法、例えば蒸
着法やスパッタ法を用いて、Ａｇ以外の導電材料の薄膜
を形成しても一向に構わない。上面電極１２１〜１２４
と下面電極１３１〜１３４とは、それぞれ仮に接続さ
れ、１００℃の絶縁油中において４ｋＶ／ｍｍの電圧を
印加して、板厚方向に一様に分極する分極処理を圧電磁
器板１１全体に施した。続いて導線をハンダを用いて接
続することにより、外部端子１４，１５，１６，１７を
取り出した。その際、ハンダの接続位置は、それぞれ振
動の節になるように各電極の中心部から取り出すように
した。(Example 1) As an example of a piezoelectric ceramic transformer according to the present invention, a piezoelectric ceramic transformer having the structure shown in Fig. 1 was produced. The material of the piezoelectric ceramic plate 11 is PZT.
(PbZrO 3 -PbTiO 3) system using a piezoelectric ceramic material. First, the fired piezoelectric ceramic block is cut with a diamond cutter and polished into parallel planes using # 3000 SiC polishing powder to obtain a length of 10 mm and a width of 8 m.
A piezoelectric ceramic plate having a thickness of 1 mm and a thickness of 1 mm is prepared. The electrodes 121 to 124 and 131 to 134 were formed by screen-printing and firing Ag paste on the piezoelectric ceramic plate.
These external electrodes may be formed by forming a thin film of a conductive material other than Ag by using a method other than coating and firing, such as vapor deposition or sputtering. Top electrodes 121 to 124
The lower electrodes 131 to 134 are tentatively connected to each other, and a voltage of 4 kV / mm is applied in insulating oil at 100 ° C. to perform a polarization treatment for uniformly polarizing the piezoelectric ceramic plate 11 in the plate thickness direction. did. Subsequently, the external terminals 14, 15, 16 and 17 were taken out by connecting the conductive wires with solder. At that time, the connection position of the solder was taken out from the central portion of each electrode so as to become a node of vibration.
【００２０】この圧電磁器トランスの幅縦振動４次モー
ドの共振周波数は、アドミタンスの周波数特性から８２
０ｋＨｚと測定された。この圧電磁器トランスに１ｋΩ
の負荷抵抗を接続したところ、入力電圧３０Ｖに対して
２４Ｖの出力電圧が得られ、このときの出力電力は０．
５７Ｗであった。The resonance frequency of the fourth longitudinal vibration mode of the piezoelectric ceramic transformer is 82 from the frequency characteristic of admittance.
It was measured as 0 kHz. 1kΩ for this piezoelectric ceramic transformer
When a load resistance of No. is connected, an output voltage of 24V is obtained for an input voltage of 30V, and the output power at this time is 0.
It was 57W.
【００２１】（実施例２）実施例１に続いて図３に示し
た構成の圧電磁器トランスを作製した。作製手順は実施
例１とほぼ同様であるが、本実施例では、分極方向の違
う領域が存在するため、電極３２１〜３２４及び３３１
〜３３４から分極用導線を取り出し、領域３１１と３１
４を圧電磁器板の板厚方向に上向き方向に分極した後、
領域３１２と３１３を下向き方向に分極した。分極処理
の後で仮の導線の接続を外して、外部端子３４，３５，
３６，３７を接続した。Example 2 Following the example 1, a piezoelectric ceramic transformer having the structure shown in FIG. 3 was produced. The manufacturing procedure is almost the same as that of the first embodiment, but in this embodiment, since there are regions having different polarization directions, the electrodes 321 to 324 and 331 are formed.
~ 334, take out the polarization conductors and extract the regions 311 and 31.
4 is polarized upward in the thickness direction of the piezoelectric ceramic plate,
Regions 312 and 313 were polarized downward. After the polarization treatment, the temporary conductors are disconnected and the external terminals 34, 35,
36 and 37 were connected.
【００２２】この圧電磁器トランスの幅縦振動４次モー
ドの共振周波数は、アドミタンスの周波数特性から８３
２ｋＨｚと測定された。この圧電磁器トランスに１ｋΩ
の負荷抵抗を接続したところ、入力電圧３０Ｖに対して
２２Ｖの出力電圧が得られ、このときの出力電力は０．
４８Ｗであった。The resonance frequency of the fourth longitudinal vibration mode of the piezoelectric ceramic transformer is 83 from the frequency characteristic of admittance.
It was measured at 2 kHz. 1kΩ for this piezoelectric ceramic transformer
When the load resistance of No. 2 is connected, an output voltage of 22V is obtained for an input voltage of 30V, and the output power at this time is 0.
It was 48W.
【００２３】[0023]
【発明の効果】以上説明したように本発明の圧電磁器ト
ランスは、縦振動高次モードを用いて圧電磁器板を励振
させて、電圧を出力させるため、数百ｋＨｚ〜１ＭＨｚ
以上の高周波帯で使用することができる。さらに高周波
化が実現できることから、非常に小型・薄型にすること
ができる。さらに、電極の分割個数に対応した振動モー
ドで圧電磁器板を励振駆動するため、圧電磁器板が発生
する電圧を効率良く取り出すことができる。さらに、圧
電磁器板の駆動部と発電部の間に、幅方向縦振動モード
による振動にてエネルギーの伝送を行うため、高電力化
・高効率化を図ることができる。As described above, in the piezoelectric ceramic transformer of the present invention, the piezoelectric ceramic plate is excited by using the longitudinal vibration higher order mode to output the voltage, and therefore, several hundred kHz to 1 MHz.
It can be used in the above high frequency band. Furthermore, since higher frequencies can be realized, it can be made extremely small and thin. Further, since the piezoelectric ceramic plate is driven to be excited in the vibration mode corresponding to the number of divided electrodes, the voltage generated by the piezoelectric ceramic plate can be efficiently extracted. Further, since energy is transmitted between the drive unit and the power generation unit of the piezoelectric ceramic plate by vibration in the widthwise longitudinal vibration mode, higher power and higher efficiency can be achieved.
【図１】（ａ）は本発明の請求項１に記載した圧電磁器
トランスを示す斜視図、（ｂ）は同断面図である。1A is a perspective view showing a piezoelectric ceramic transformer according to claim 1 of the present invention, and FIG. 1B is a sectional view of the same.
【図２】本発明の請求項１に記載した圧電磁器トランス
の変位，歪，電荷の関係を示す分布図である。FIG. 2 is a distribution diagram showing a relationship among displacement, strain and electric charge of the piezoelectric ceramic transformer according to claim 1 of the present invention.
【図３】（ａ）は本発明の請求項２に記載した圧電磁器
トランスを示す斜視図、（ｂ）は同断面図である。3A is a perspective view showing a piezoelectric ceramic transformer according to claim 2 of the present invention, and FIG. 3B is a sectional view of the same.
【図４】本発明の請求項２に記載した圧電磁器トランス
の変位，歪，電荷の関係を示す分布図である。FIG. 4 is a distribution diagram showing a relationship among displacement, strain, and electric charge of the piezoelectric ceramic transformer according to claim 2 of the present invention.
【図５】圧電磁器トランスの集中定数等価回路図であ
る。FIG. 5 is a lumped constant equivalent circuit diagram of the piezoelectric ceramic transformer.
【図６】従来のローゼン型圧電磁器トランスを示す斜視
図である。FIG. 6 is a perspective view showing a conventional Rosen type piezoelectric ceramic transformer.
１１，３１ 圧電磁器板 ６３，６４，６５，１２１，１２２，１２３，１２４，
１３１，１３２，１３３，１３４，３２１，３２２，３
２３，３２４，３３１，３３２，３３３，３３４ 電極 １４，１５，１６，１７，３４，３５，３６，３７，６
６，６７，６８ 外部端子 ６１ 駆動部 ６２ 発電部11, 31 Piezoelectric ceramic plate 63, 64, 65, 121, 122, 123, 124,
131, 132, 133, 134, 321, 322, 3
23, 324, 331, 332, 333, 334 Electrodes 14, 15, 16, 17, 34, 35, 36, 37, 6
6, 67, 68 External terminal 61 Drive section 62 Power generation section
Claims (4)
対とを有する圧電磁器トランスであって、 圧電磁器板は、板状の圧電振動体であって、板厚方向に
一様に分極され、幅方向縦振動モードの共振周波数近傍
の周波数の交流電圧を入力として励振し、交流電圧を出
力するものであり、 対をなす電極は、圧電磁器板の板厚方向の端面に、対向
した位置で、かつ、その幅方向に該圧電磁器板の励振モ
ードに対応して分割して設けたものであり、 対をなす外部端子の一方は、圧電磁器板に交流電圧を印
加する入力端であり、他方は、圧電磁器板の電圧をピッ
クアップする出力端であり、 該対をなす外部端子は、圧電磁器板の板厚方向の一端面
側で分割電極を１個おきに電圧の入力側と電圧の出力側
とに分離して接続したものであることを特徴とする圧電
磁器トランス。1. A piezoelectric ceramic transformer having a piezoelectric ceramic plate, a pair of electrodes, and a pair of external terminals, wherein the piezoelectric ceramic plate is a plate-shaped piezoelectric vibrating body, and is uniform in the plate thickness direction. Is excited by the input of an AC voltage having a frequency near the resonance frequency of the widthwise longitudinal vibration mode, and outputs an AC voltage.The paired electrodes are at the end face in the plate thickness direction of the piezoelectric ceramic plate. It is provided by dividing the piezoelectric ceramic plate at the opposing position in the width direction according to the excitation mode of the piezoelectric ceramic plate, and one of the paired external terminals is an input for applying an AC voltage to the piezoelectric ceramic plate. The other end is an output end for picking up the voltage of the piezoelectric ceramic plate, and the paired external terminals are provided with voltage input every other split electrode on one end face side in the plate thickness direction of the piezoelectric ceramic plate. Side and the output side of the voltage are separated and connected. That the piezoelectric ceramic transformer.
周波数近傍の周波数の交流電圧を印加し、該圧電磁器板
を励振させて交流電圧を出力させる圧電磁器トランスの
駆動方法であって、 圧電磁器板は、板厚方向に一様に分極された板状の圧電
振動体であって、板厚方向の両端面に、対向した位置
で、その幅方向に２以上のｐ個に分割して設けた対をな
す電極を有し、 圧電磁器板に交流電圧を印加する入力用外部端子と、圧
電磁器板の電圧をピックアップする出力用外部端子とに
より、圧電磁器板の板厚方向の一端面側にてｐ個に分割
された電極を１個おきに電圧の入力側と電圧の出力側と
に分離して接続し、さらに入力側外部端子を電源に接続
し、かつ出力側外部端子を負荷に接続し、 前記幅方向縦振動モードを、前記電極が分割された個数
と同数のｐ次モードに設定し、前記圧電磁器板を励振し
て駆動することを特徴とする圧電磁器トランスの駆動方
法。2. A method of driving a piezoelectric ceramic transformer, wherein an AC voltage having a frequency near a resonance frequency of a longitudinal vibration mode in a width direction is applied to the piezoelectric ceramic plate to excite the piezoelectric ceramic plate to output an AC voltage. A piezoelectric ceramic plate is a plate-shaped piezoelectric vibrating body that is uniformly polarized in the plate thickness direction, and is divided into two or more p pieces in the width direction at positions facing both end faces in the plate thickness direction. The external electrodes for input that apply an AC voltage to the piezoelectric ceramic plate and the external terminals for output that pick up the voltage of the piezoelectric ceramic plate have a pair of electrodes that are arranged in the plate thickness direction of the piezoelectric ceramic plate. Every other electrode divided into p pieces on the end face side is separately connected to the voltage input side and the voltage output side, and the input side external terminal is connected to the power source, and the output side external terminal is connected. Connected to the load, the widthwise longitudinal vibration mode, the electrode divided A method of driving a piezoelectric ceramic transformer, characterized by setting the same number of p-order modes as that of the number and driving the piezoelectric ceramic plates by exciting them.
対とを有する圧電磁器トランスであって、 圧電磁器板は、板状の圧電振動体であって、板厚方向に
分極され、幅方向縦振動モードの共振周波数近傍の周波
数の交流電圧を入力として励振し、交流電圧を出力する
ものであり、駆動部と発電部とを有し、 駆動部と発電部は、圧電磁器板の幅方向に分離して配置
され、 駆動部は、圧電磁器板の幅方向に沿って分割され、か
つ、その分極方向が交互に異なる領域からなり、 発電部は、圧電磁器板の幅方向に沿って分割され、か
つ、その分極方向が交互に異なる領域からなり、 対をなす電極は、圧電磁器板の板厚方向の両端面に、対
向した位置で、かつ、駆動部及び発電部の各分割領域毎
に分割して設けたものであり、 対をなす外部端子の一方は、圧電磁器板に交流電圧を印
加する入力端であり、他方は圧電磁器板の電圧をピック
アップする出力端であり、 該対をなす外部端子は、圧電磁器板の板厚方向の一端面
側で分割電極を駆動部側と発電部側とに分離して接続し
たものであることを特徴とする圧電磁器トランス。3. A piezoelectric ceramic transformer having a piezoelectric ceramic plate, a pair of electrodes, and a pair of external terminals, wherein the piezoelectric ceramic plate is a plate-shaped piezoelectric vibrating body and is polarized in a plate thickness direction. , Which excites by inputting an AC voltage having a frequency near the resonance frequency of the widthwise longitudinal vibration mode and outputs an AC voltage, has a drive unit and a power generation unit, and the drive unit and the power generation unit are piezoelectric ceramic plates. The drive part is divided along the width direction of the piezoelectric ceramic plate, and the polarization direction of the driving part is divided into different regions.The power generation part is divided in the width direction of the piezoelectric ceramic plate. The electrodes, which are divided along each other and have polarization directions that are different from each other, are paired with each other. One of the external terminals that make a pair Is an input end for applying an AC voltage to the piezoelectric ceramic plate, the other is an output end for picking up the voltage of the piezoelectric ceramic plate, and the pair of external terminals is one end surface side of the piezoelectric ceramic plate in the plate thickness direction. 2. A piezoelectric ceramic transformer characterized in that the divided electrodes are separately connected to the drive unit side and the power generation unit side.
周波数近傍の周波数の交流電圧を印加し、該圧電磁器板
を励振させて交流電圧を出力させる圧電磁器トランスの
駆動方法であって、 圧電磁器板は、板厚方向に分極された板状の圧電振動体
であって、圧電磁器板の幅方向に沿ってｍ個に分割さ
れ、かつ、その分極方向が交互に異なる領域の駆動部
と、圧電磁器板の幅方向に沿ってｎ個に分割され、か
つ、その分極方向が交互に異なる領域の発電部とを有
し、 駆動部及び発電部の各分割領域は、圧電磁器板の板厚方
向の端面の対向した位置に設けられた対をなす電極を有
し、 圧電磁器板に交流電圧を印加する入力側外部端子と、圧
電磁器板の電圧をピックアップする出力側外部端子とに
より、圧電磁器板の板厚方向の一端面側にてｍ個とｎ個
とに分割された電極を駆動部側と発電部側とに分離して
接続し、さらに入力側外部端子を電源に接続し、かつ出
力側外部端子を負荷に接続し、 前記幅方向縦振動モードを、前記電極が分割された（ｍ
＋ｎ）個と同数の（ｍ＋ｎ）次モードに設定し、前記圧
電磁器板を励振して駆動することを特徴とする圧電磁器
トランスの駆動方法。4. A method of driving a piezoelectric ceramic transformer, wherein an AC voltage having a frequency near a resonance frequency of a widthwise longitudinal vibration mode is applied to the piezoelectric ceramic plate to excite the piezoelectric ceramic plate to output an AC voltage. The piezoelectric ceramic plate is a plate-shaped piezoelectric vibrating body that is polarized in the plate thickness direction, and is divided into m pieces along the width direction of the piezoelectric ceramic plate, and the driving units in regions in which the polarization directions are alternately different. And a power generation part divided into n pieces along the width direction of the piezoelectric ceramic plate, and the polarization directions thereof are alternately different. Each divided region of the drive part and the power generation part is It has a pair of electrodes provided at opposite positions on the end face in the plate thickness direction, and has an input-side external terminal that applies an AC voltage to the piezoelectric ceramic plate and an output-side external terminal that picks up the voltage of the piezoelectric ceramic plate. , N and n on one end surface side of the piezoelectric ceramic plate in the plate thickness direction The divided electrodes are separately connected to the drive unit side and the power generation unit side, the input side external terminal is connected to the power source, and the output side external terminal is connected to the load. Mode, the electrodes are split (m
A driving method of a piezoelectric ceramic transformer, characterized by setting the same number of (m + n) -th mode as + n) and exciting and driving the piezoelectric ceramic plate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5126837A JP2508964B2 (en) | 1993-05-28 | 1993-05-28 | Piezoelectric transformer and driving method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5126837A JP2508964B2 (en) | 1993-05-28 | 1993-05-28 | Piezoelectric transformer and driving method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH06338641A true JPH06338641A (en) | 1994-12-06 |
| JP2508964B2 JP2508964B2 (en) | 1996-06-19 |
Family
ID=14945127
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5126837A Expired - Lifetime JP2508964B2 (en) | 1993-05-28 | 1993-05-28 | Piezoelectric transformer and driving method thereof |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2508964B2 (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5929554A (en) * | 1994-12-30 | 1999-07-27 | Mitsui Chemicals, Inc. | Piezoelectric transformer |
| US5939818A (en) * | 1995-02-15 | 1999-08-17 | Nec Corporation | Piezoelectric transformer, its manufacturing method and its driving method |
| JP2002141572A (en) * | 2000-10-31 | 2002-05-17 | Kyocera Corp | Piezoelectric transformer |
| FR2954014A1 (en) * | 2009-12-11 | 2011-06-17 | St Microelectronics Tours Sas | Acoustic galvanic insulating device, has medium permitting transmission of acoustic waves and placed between transformation units comprising ultrasonic transducers, where medium comprises insulator |
| JP2014531833A (en) * | 2011-09-23 | 2014-11-27 | クアルコム，インコーポレイテッド | Piezoelectric resonator with combined thickness and width vibration modes |
-
1993
- 1993-05-28 JP JP5126837A patent/JP2508964B2/en not_active Expired - Lifetime
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5929554A (en) * | 1994-12-30 | 1999-07-27 | Mitsui Chemicals, Inc. | Piezoelectric transformer |
| US5939818A (en) * | 1995-02-15 | 1999-08-17 | Nec Corporation | Piezoelectric transformer, its manufacturing method and its driving method |
| JP2002141572A (en) * | 2000-10-31 | 2002-05-17 | Kyocera Corp | Piezoelectric transformer |
| FR2954014A1 (en) * | 2009-12-11 | 2011-06-17 | St Microelectronics Tours Sas | Acoustic galvanic insulating device, has medium permitting transmission of acoustic waves and placed between transformation units comprising ultrasonic transducers, where medium comprises insulator |
| JP2014531833A (en) * | 2011-09-23 | 2014-11-27 | クアルコム，インコーポレイテッド | Piezoelectric resonator with combined thickness and width vibration modes |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2508964B2 (en) | 1996-06-19 |
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