JPH0646312U - Displacement measuring device - Google Patents
Displacement measuring deviceInfo
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- JPH0646312U JPH0646312U JP8726592U JP8726592U JPH0646312U JP H0646312 U JPH0646312 U JP H0646312U JP 8726592 U JP8726592 U JP 8726592U JP 8726592 U JP8726592 U JP 8726592U JP H0646312 U JPH0646312 U JP H0646312U
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- piezoelectric element
- displacement
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Abstract
(57)【要約】
【目的】 実駆動条件下での圧電素子の変位を測定する
ことができる変位測定装置を提供する。
【構成】 圧電素子５を挟持し、該圧電素子５に電圧を
印加する一対の電極１１、１２と、圧電素子５に荷重を
負荷するための荷重負荷手段２と、圧電素子５の温度を
制御するための温度制御手段３と、圧電素子５の変位を
測定するための変位測定手段４とよりなる変位測定装
置。
【効果】 荷重を負荷し、温度を制御した実駆動条件下
での圧電素子の変位を測定することができる。
(57) [Summary] [Object] To provide a displacement measuring device capable of measuring the displacement of a piezoelectric element under actual driving conditions. A pair of electrodes 11 and 12 for sandwiching the piezoelectric element 5 and applying a voltage to the piezoelectric element 5, a load applying means 2 for applying a load to the piezoelectric element 5, and a temperature of the piezoelectric element 5 are controlled. A displacement measuring device comprising temperature control means 3 for controlling the displacement and displacement measuring means 4 for measuring the displacement of the piezoelectric element 5. [Effect] It is possible to measure the displacement of the piezoelectric element under actual driving conditions in which a load is applied and the temperature is controlled.
Description
【０００１】[0001]
本考案は、圧電素子の実駆動条件下における変位を測定するための装置に関す るものである。 The present invention relates to an apparatus for measuring displacement of a piezoelectric element under actual driving conditions.
【０００２】[0002]
圧電素子は、圧電体とその両端に取り付けた銀等の電極とよりなる構造であり 、電極に電圧が印加されると圧電素子が変形することを利用して、電圧を変位ま たは力に変換するものである。この圧電素子は、上記特性により自動車部品、精 密工作機械等のアクチュエータ、ＶＴＲ、超音波モータ等に利用されている。 A piezoelectric element has a structure consisting of a piezoelectric body and electrodes such as silver attached to both ends of the piezoelectric body.It utilizes the fact that the piezoelectric element deforms when a voltage is applied to the electrodes, so that the voltage can be displaced or applied to a force. It is to convert. Due to the above characteristics, this piezoelectric element is used in automobile parts, actuators for precision machine tools, VTRs, ultrasonic motors and the like.
【０００３】 特に、圧電素子は、変位が微小であるために制御精度と応答速度が必要な機器 用素子として利用され、例えば、アクチュエータとして使用する場合には、数十 枚積層し、さらに荷重を負荷して変位を調整している。そのため、圧電素子単板 の実駆動条件下での変位を測定する必要がある。In particular, a piezoelectric element is used as an element for an apparatus that requires control accuracy and response speed because its displacement is very small. For example, when it is used as an actuator, dozens of layers are stacked and a load is applied. The load is adjusted to adjust the displacement. Therefore, it is necessary to measure the displacement of the piezoelectric element single plate under actual driving conditions.
【０００４】 従来のこのような圧電素子の変位を測定する装置として、差動トランスおよび うず電流方式の電子マイクロメータ等がある。圧電素子の変位が２５〜３０μｍ とかなり大きい場合には、上記装置で変位を測定することができる。しかし、圧 電素子単板の変位は０．５〜１．０μｍと微小の場合が多く、上記装置では測定 が困難である。Conventional devices for measuring the displacement of such a piezoelectric element include a differential transformer and an eddy current type electronic micrometer. When the displacement of the piezoelectric element is as large as 25 to 30 μm, the displacement can be measured by the above device. However, the displacement of the piezoelectric element single plate is often as small as 0.5 to 1.0 μm, and it is difficult to measure with the above device.
【０００５】[0005]
上記０．５〜１．０μｍの非常に小さい変位を測定するには、レーザー干渉を 使用した装置が可能である。 To measure the very small displacement of 0.5 to 1.0 μm, an apparatus using laser interference is possible.
【０００６】 しかし、レーザー干渉を使用した場合は測定系が複雑になるために、広温度域 下あるいは荷重負荷下では精度よく変位を測定することが困難である。However, when laser interference is used, the measurement system becomes complicated, so that it is difficult to accurately measure the displacement under a wide temperature range or under a load.
【０００７】 本考案は、上記従来技術の問題点に鑑みなされたものであり、圧電素子の実駆 動条件下における変位を測定することができる装置を提供することを目的とする 。The present invention has been made in view of the above-mentioned problems of the conventional art, and an object of the present invention is to provide an apparatus capable of measuring a displacement of a piezoelectric element under an actual driving condition.
【０００８】[0008]
本考案は、圧電素子の駆動時の変位を測定するための装置であって、圧電素子 を挟持し、該圧電素子に電圧を印加するための一対の電極と、上記圧電素子に荷 重を負荷するための荷重負荷手段と、上記圧電素子の温度を制御するための温度 制御手段と、上記圧電素子の変位を測定するための変位測定手段とよりなること を特徴とする変位測定装置である。 The present invention is a device for measuring the displacement of a piezoelectric element during driving, in which a pair of electrodes for sandwiching the piezoelectric element and applying a voltage to the piezoelectric element, and a load for the piezoelectric element are loaded. Displacement measuring device comprising: load applying means for controlling the temperature of the piezoelectric element; temperature control means for controlling the temperature of the piezoelectric element; and displacement measuring means for measuring the displacement of the piezoelectric element.
【０００９】[0009]
荷重負荷手段により圧電素子に任意の荷重を精密に負荷するとともに温度制御 手段により圧電素子を任意の温度に制御することができる。そのため、アクチュ エータ等として使用する実駆動条件を再現することができ、この実駆動条件下で の圧電素子の変位を測定することができる。 It is possible to precisely load an arbitrary load on the piezoelectric element by the load applying means and to control the piezoelectric element to an arbitrary temperature by the temperature control means. Therefore, it is possible to reproduce the actual driving condition used as an actuator or the like, and it is possible to measure the displacement of the piezoelectric element under this actual driving condition.
【００１０】[0010]
本考案の変位測定装置は、圧電素子の実駆動条件下における変位を測定するこ とができる。 The displacement measuring device of the present invention can measure the displacement of the piezoelectric element under actual driving conditions.
【００１１】[0011]
以下、本考案の実施例を説明する。 Embodiments of the present invention will be described below.
【００１２】 （実施例） 図１に本実施例の変位測定装置の要部欠截正面図、図２にその試料保持部の断 面図を示す。この変位測定装置は、試料保持部（試料ホルダ）６内に、圧電素子 ５を配置して該圧電素子５に電圧を印加する一対の電極１１、１２と、圧電素子 ５の周囲に熱媒体を循環させて圧電素子５の温度を制御するための温度制御部３ とが配置され、さらに、圧電素子５に荷重を負荷するバネ２と、圧電素子５の変 位に伴う電極の移動量を測定するレーザー変位計４を備えたものである。(Embodiment) FIG. 1 shows a fragmentary front view of a main part of a displacement measuring apparatus according to this embodiment, and FIG. In this displacement measuring device, a piezoelectric element 5 is arranged in a sample holder (sample holder) 6, a pair of electrodes 11 and 12 for applying a voltage to the piezoelectric element 5, and a heat medium around the piezoelectric element 5. A temperature control unit 3 for circulating and controlling the temperature of the piezoelectric element 5 is arranged, and further, the spring 2 for applying a load to the piezoelectric element 5 and the amount of movement of the electrode due to the displacement of the piezoelectric element 5 are measured. The laser displacement meter 4 is provided.
【００１３】 試料ホルダ６の試料ホルダ外筒６１の中にはセラミックスの円筒が挿入され、 さらにその円筒中に金属よりなる正、負の一対の電極１１、１２が配置されてい る。なお、この正電極１１の平面図を図３に、負電極１２の平面図を図４に示す 。この一対の電極の間に圧電素子５が配置されるようになっている。圧電素子５ の位置調節はガイド６２により行うことができる。また、負電極１２の下、正電 極１１の上にはそれぞれ電極に電圧を印加するための電圧印加プレート１３、１ ４が設けられている。圧電素子５への電圧の印加は、上記電圧印加プレート１３ 、１４を介して行う。なお、正電極１１の上部にある電圧印加プレート１４は圧 電素子５に荷重を負荷するための荷重負荷板としても働く。また、正電極１１、 負電極１２の圧電素子５との接触面における平面度、粗さは、圧電素子５と正電 極１１、負電極１２とが均等に接触するためにＲｚで１μｍ以下としている。ま た、外部に電流が漏れないように正電極１１の上部にある電圧印加プレート１４ 上、および負電極１２の下部にある電圧印加プレート１３の下に絶縁板７が設け られている。A ceramic cylinder is inserted in the sample holder outer cylinder 61 of the sample holder 6, and a pair of positive and negative electrodes 11 and 12 made of metal are arranged in the cylinder. A plan view of the positive electrode 11 is shown in FIG. 3, and a plan view of the negative electrode 12 is shown in FIG. The piezoelectric element 5 is arranged between the pair of electrodes. The position of the piezoelectric element 5 can be adjusted by the guide 62. Further, below the negative electrode 12 and above the positive electrode 11, voltage application plates 13 and 14 for applying a voltage to the electrodes are provided, respectively. The voltage is applied to the piezoelectric element 5 via the voltage applying plates 13 and 14. The voltage applying plate 14 above the positive electrode 11 also functions as a load applying plate for applying a load to the piezoelectric element 5. Further, the flatness and roughness of the contact surface between the positive electrode 11 and the negative electrode 12 with the piezoelectric element 5 are set to Rz of 1 μm or less so that the piezoelectric element 5 and the positive electrode 11 and the negative electrode 12 are evenly contacted with each other. There is. Further, an insulating plate 7 is provided above the voltage applying plate 14 above the positive electrode 11 and below the voltage applying plate 13 below the negative electrode 12 so that the current does not leak to the outside.
【００１４】 温度制御部３は、変位測定装置本体とは別に設けられ、そこで制御された熱媒 体をポンプ等により試料ホルダ６の側面に設けた熱媒体出入口３２から試料ホル ダ６中の熱媒体室３１に循環させる。循環される熱媒体は熱媒体室３１において 圧電素子５の側面に接するように流れる。この熱媒体の温度を制御することによ り圧電素子の温度を制御できる。圧電素子の温度の測定は、試料ホルダの側面に 設けた熱電対用穴３３に熱電対（図示せず）を挿入し、該熱電対により行う。The temperature control unit 3 is provided separately from the displacement measuring apparatus main body, and the heat medium controlled there is supplied from the heat medium inlet / outlet 32 provided on the side surface of the sample holder 6 by a pump or the like to the heat in the sample holder 6. The medium chamber 31 is circulated. The circulating heat medium flows so as to contact the side surface of the piezoelectric element 5 in the heat medium chamber 31. By controlling the temperature of this heat medium, the temperature of the piezoelectric element can be controlled. The temperature of the piezoelectric element is measured by inserting a thermocouple (not shown) into the thermocouple hole 33 provided on the side surface of the sample holder and using the thermocouple.
【００１５】 バネ２は、上下方向に配置され、電圧印加プレート１４の上面に接続され、正 電極１１に荷重がかかるようになっている。バネ２とプレート１４との接続部分 ７は絶縁材よりなる板状となっている。バネ２の上部にはハンドル９が設けられ 、このハンドル９を回転することによりバネ２の圧縮、伸長を行う。バネ２の圧 縮によりプレート１４に荷重が負荷され、この荷重が正電極１１を介して圧電素 子５に伝わる。また、圧電素子５に発生する応力（圧縮応力）の測定は、バネ２ の上部に設けた圧力センサ２１により行う。The spring 2 is arranged in the up-down direction, is connected to the upper surface of the voltage applying plate 14, and applies a load to the positive electrode 11. The connecting portion 7 between the spring 2 and the plate 14 is a plate made of an insulating material. A handle 9 is provided above the spring 2, and the handle 9 is rotated to compress and extend the spring 2. A load is applied to the plate 14 by the compression of the spring 2, and this load is transmitted to the piezoelectric element 5 via the positive electrode 11. Further, the stress (compressive stress) generated in the piezoelectric element 5 is measured by the pressure sensor 21 provided above the spring 2.
【００１６】 レーザー変位計４は、正電極１１の上部に設けられ、圧電素子５の変位に伴う 正電極１１の移動量を測定する。すなわち、圧電素子５に荷重を負荷する手段が バネのような弾性体であり、かつその荷重負荷を正電極１１を介して行う。この にように、正電極１１に荷重を負荷しているものが弾性体であるため、該正電極 １１は移動可能である。圧電素子５が変位することにより該圧電素子５と接して いる正電極１１が移動することになるため、この正電極１１の移動量（正電極１ １の上面１１１の移動量を測定することにより圧電素子５の微小な変位も測定す ることができる。The laser displacement meter 4 is provided above the positive electrode 11 and measures the amount of movement of the positive electrode 11 due to the displacement of the piezoelectric element 5. That is, the means for applying a load to the piezoelectric element 5 is an elastic body such as a spring, and the load is applied via the positive electrode 11. As described above, since the one that applies the load to the positive electrode 11 is the elastic body, the positive electrode 11 can move. Since the positive electrode 11 in contact with the piezoelectric element 5 moves due to the displacement of the piezoelectric element 5, the moving amount of this positive electrode 11 (by measuring the moving amount of the upper surface 111 of the positive electrode 11) It is also possible to measure a minute displacement of the piezoelectric element 5.
【００１７】 また、本装置の下部には振動が装置に伝達しないように防振ゴム８が設けられ ている。Further, a vibration-proof rubber 8 is provided at the lower part of the device so that vibrations are not transmitted to the device.
【００１８】 この装置を用いて、以下のように圧電素子の微小変位を測定した。Using this device, the minute displacement of the piezoelectric element was measured as follows.
【００１９】 圧電体となるＰＺＴ（ジルコン酸チタン酸鉛）よりなるセラミックスの微粉末 をプレス成形し、その後ＣＩＰ（冷間静水圧プレス）および脱脂を行い、さらに 電気炉で１２００℃、４時間焼成してペレットとした。このペレットを外径１２ ｍｍ、厚さ０．５ｍｍに加工し、表面を＃６００の砥石で仕上げてセラミックス 圧電体を作製した。さらに、この圧電体の両面全体に銀をスクリーン印刷により 膜厚７μｍで取り付けて圧電素子とした。A ceramic fine powder made of PZT (lead zirconate titanate), which is a piezoelectric body, is press-molded, then CIP (cold isostatic press) and degreasing are performed, and further fired at 1200 ° C. for 4 hours in an electric furnace. And made into pellets. The pellet was processed into an outer diameter of 12 mm and a thickness of 0.5 mm, and the surface was finished with a # 600 grindstone to produce a ceramic piezoelectric body. Further, silver was attached to both sides of the piezoelectric body by screen printing so as to have a film thickness of 7 μm to form a piezoelectric element.
【００２０】 得られた圧電素子を変位測定装置の試料保持部６中の正電極１１と負電極１２ との間に設置した。なお、正電極１１と負電極１２における圧電素子と接触する 部分は圧電素子の外径と同様に１２ｍｍとした。圧電素子５に発生する圧縮応力 は０〜６０ＭＰａ、印加電圧は振幅が８００Ｖの０．１Ｈｚのｓｉｎ波の条件と した。熱媒体としてはシリコンオイルを使用した。この条件で圧電素子の荷重負 荷下での変位特性を測定した。変位測定は、レーザー変位計４の出力をパソコン およびＸ−Ｙレコーダに入力して変位を測定した。図５に圧縮応力と変位との関 係を示す。The obtained piezoelectric element was placed between the positive electrode 11 and the negative electrode 12 in the sample holder 6 of the displacement measuring device. The portion of the positive electrode 11 and the negative electrode 12 in contact with the piezoelectric element was 12 mm, which was the same as the outer diameter of the piezoelectric element. The compressive stress generated in the piezoelectric element 5 was set to 0 to 60 MPa, and the applied voltage was set to a 0.1 Hz sin wave with an amplitude of 800 V. Silicon oil was used as the heat medium. Under this condition, the displacement characteristics of the piezoelectric element under load were measured. The displacement was measured by inputting the output of the laser displacement meter 4 into a personal computer and an XY recorder. Figure 5 shows the relationship between compressive stress and displacement.
【００２１】 次に、温度制御、荷重負荷下の変位特性の測定例を示す。測定条件は、圧縮応 力が０〜６０ＭＰａ、温度が−３０℃〜１４０℃、印加電圧が振幅８００Ｖの０ ．１Ｈｚのｓｉｎ波の条件とした。変位の測定は上記と同様である。Next, an example of measurement of displacement characteristics under temperature control and load application will be shown. The measurement conditions were as follows: compression force was 0 to 60 MPa, temperature was -30 to 140 ° C., and applied voltage was 0. The condition was a sin wave of 1 Hz. The displacement measurement is the same as above.
【００２２】 図６に荷重負荷下における温度と変位との関係を示す。FIG. 6 shows the relationship between temperature and displacement under load.
【００２３】 図５および図６より、圧電素子の変位を荷重負荷下および温度制御下で精度よ く測定することができ、変位の圧縮応力依存性、温度依存性が明らかになった。From FIGS. 5 and 6, the displacement of the piezoelectric element can be accurately measured under load and temperature control, and the compressive stress dependency and the temperature dependency of the displacement are clarified.
【００２４】 なお、本実施例において、上記バネ２の代わりにバネ定数が同様なものであれ ばどのような弾性体も適用できる。また、温度制御のための熱媒体としてシリコ ンオンルの代わりにそれ以外の絶縁性のある熱媒体も適用できる。In the present embodiment, any elastic body can be applied instead of the spring 2 as long as it has the same spring constant. Further, as a heat medium for temperature control, a heat medium having an insulating property other than that can be applied instead of the silicon one.
【図１】本実施例の変位測定装置の要部欠截正面図FIG. 1 is a front view of a main part of a displacement measuring device according to an embodiment of the present invention.
【図２】図１の試料保持部の断面図2 is a cross-sectional view of the sample holder of FIG.
【図３】図１の正電極の正面図3 is a front view of the positive electrode of FIG.
【図４】図１の負電極の正面図FIG. 4 is a front view of the negative electrode of FIG.
【図５】本実施例の変位測定装置により測定した圧電素
子の変位と圧縮応力との関係を示す線図FIG. 5 is a diagram showing the relationship between the displacement of the piezoelectric element and the compressive stress measured by the displacement measuring device of this embodiment.
【図６】本実施例の変位測定装置により測定した荷重負
荷下における圧電素子の変位と温度との関係を示す線図FIG. 6 is a diagram showing the relationship between the displacement of the piezoelectric element and the temperature under a load load measured by the displacement measuring device of the present embodiment.
２ バネ ３ 温度制御部 ４ レーザー変位計 ５ 圧電素子 ６ 試料ホルダ １１ 正電極 １２ 負電極 ２１ 圧力センサ ３１ 熱媒体室 2 spring 3 temperature control unit 4 laser displacement meter 5 piezoelectric element 6 sample holder 11 positive electrode 12 negative electrode 21 pressure sensor 31 heat medium chamber
Claims (1)
の装置であって、 圧電素子を挟持し、該圧電素子に電圧を印加するための
一対の電極と、 上記圧電素子に荷重を負荷するための荷重負荷手段と、 上記圧電素子の温度を制御するための温度制御手段と、 上記圧電素子の変位を測定するための変位測定手段とよ
りなることを特徴とする変位測定装置。1. A device for measuring displacement of a piezoelectric element during driving, comprising: a pair of electrodes for sandwiching the piezoelectric element and applying a voltage to the piezoelectric element; and a load applied to the piezoelectric element. A displacement measuring device comprising: a load applying means for controlling the temperature of the piezoelectric element; a temperature controlling means for controlling the temperature of the piezoelectric element; and a displacement measuring means for measuring the displacement of the piezoelectric element.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1992087265U JP2580418Y2 (en) | 1992-11-25 | 1992-11-25 | Displacement measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1992087265U JP2580418Y2 (en) | 1992-11-25 | 1992-11-25 | Displacement measuring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0646312U true JPH0646312U (en) | 1994-06-24 |
| JP2580418Y2 JP2580418Y2 (en) | 1998-09-10 |
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| JP1992087265U Expired - Fee Related JP2580418Y2 (en) | 1992-11-25 | 1992-11-25 | Displacement measuring device |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57172202A (en) * | 1981-04-17 | 1982-10-23 | Hitachi Ltd | Displacement generator |
| JPH04250336A (en) * | 1991-01-28 | 1992-09-07 | Nkk Corp | Device and method for tension test of metallic material |
-
1992
- 1992-11-25 JP JP1992087265U patent/JP2580418Y2/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57172202A (en) * | 1981-04-17 | 1982-10-23 | Hitachi Ltd | Displacement generator |
| JPH04250336A (en) * | 1991-01-28 | 1992-09-07 | Nkk Corp | Device and method for tension test of metallic material |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2580418Y2 (en) | 1998-09-10 |
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