JPS5867085A - Displacement element - Google Patents
Displacement elementInfo
- Publication number
- JPS5867085A JPS5867085A JP56166234A JP16623481A JPS5867085A JP S5867085 A JPS5867085 A JP S5867085A JP 56166234 A JP56166234 A JP 56166234A JP 16623481 A JP16623481 A JP 16623481A JP S5867085 A JPS5867085 A JP S5867085A
- Authority
- JP
- Japan
- Prior art keywords
- displacement
- substrates
- displacement element
- piezoelectric
- piezo
- 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
- 238000006073 displacement reaction Methods 0.000 title claims abstract description 50
- 239000000758 substrate Substances 0.000 claims abstract description 56
- 229910052573 porcelain Inorganic materials 0.000 abstract description 11
- 239000000853 adhesive Substances 0.000 abstract description 6
- 230000001070 adhesive effect Effects 0.000 abstract description 6
- 239000002253 acid Substances 0.000 abstract 1
- 239000003822 epoxy resin Substances 0.000 abstract 1
- 238000005259 measurement Methods 0.000 abstract 1
- 238000000034 method Methods 0.000 abstract 1
- 229920000647 polyepoxide Polymers 0.000 abstract 1
- PMTRSEDNJGMXLN-UHFFFAOYSA-N titanium zirconium Chemical compound [Ti].[Zr] PMTRSEDNJGMXLN-UHFFFAOYSA-N 0.000 abstract 1
- 239000000463 material Substances 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 230000005684 electric field Effects 0.000 description 4
- 239000004593 Epoxy Substances 0.000 description 3
- 239000000919 ceramic Substances 0.000 description 2
- 230000008602 contraction Effects 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 230000010287 polarization Effects 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- HFGPZNIAWCZYJU-UHFFFAOYSA-N lead zirconate titanate Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[Ti+4].[Zr+4].[Pb+2] HFGPZNIAWCZYJU-UHFFFAOYSA-N 0.000 description 1
- 229910052451 lead zirconate titanate Inorganic materials 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 238000007740 vapor deposition Methods 0.000 description 1
Classifications
-
- 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
- H10N30/20—Piezoelectric or electrostrictive devices with electrical input and mechanical output, e.g. functioning as actuators or vibrators
- H10N30/204—Piezoelectric or electrostrictive devices with electrical input and mechanical output, e.g. functioning as actuators or vibrators using bending displacement, e.g. unimorph, bimorph or multimorph cantilever or membrane benders
- H10N30/2041—Beam type
- H10N30/2042—Cantilevers, i.e. having one fixed end
- H10N30/2044—Cantilevers, i.e. having one fixed end having multiple segments mechanically connected in series, e.g. zig-zag type
Landscapes
- General Electrical Machinery Utilizing Piezoelectricity, Electrostriction Or Magnetostriction (AREA)
Abstract
Description
【発明の詳細な説明】
本発明は電圧印加によって長さ方向に変位する変位素子
に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a displacement element that is longitudinally displaced by voltage application.
従来、圧電型変位素子としては圧電基板の一端を支持台
に固定し、電界印加による圧電基板の伸縮による他端の
変位を用いるものである。この場合変位量は、圧電基板
の圧電定数をｄ、変位部の長きを！、印加電界をＸとし
たとき、 ｅＪＩＴＬ で表わされる。、５．！：Ｅ
は圧電基板の材料によっである値以下に限定されるので
、大きな変位量を得るにはｌを大きくする必要がある。Conventionally, as a piezoelectric displacement element, one end of a piezoelectric substrate is fixed to a support base, and the other end is displaced by expansion and contraction of the piezoelectric substrate by applying an electric field. In this case, the amount of displacement is the piezoelectric constant of the piezoelectric substrate d, and the length of the displaced part! , when the applied electric field is X, it is expressed as eJITL. ,5. ! :E
is limited to a certain value or less depending on the material of the piezoelectric substrate, so it is necessary to increase l in order to obtain a large amount of displacement.
しかしながら、ｌを大きくすると、変位素子全体の長さ
が著しく犬きくなるので、比較的小さい形状で大きな変
位量を得ることは従来不可能であった。However, if l is increased, the length of the entire displacement element becomes significantly longer, so it has conventionally been impossible to obtain a large amount of displacement with a relatively small shape.
本発明は上記の欠点を除去し、比較的小さな形状で大き
な変位量の得られる変位素子を提供する。The present invention eliminates the above-mentioned drawbacks and provides a displacement element capable of obtaining a large amount of displacement with a relatively small shape.
すなわち、本発明は、長さ方向に変位する複数個の圧電
基板を長さ方向に平行で並列に配置し、かつ隣接する圧
電基板を長さ方向の一端で固定し。That is, in the present invention, a plurality of piezoelectric substrates that are displaced in the length direction are arranged parallel to each other in the length direction, and adjacent piezoelectric substrates are fixed at one end in the length direction.
更に電圧印加時の隣接する圧電基板の長さ方向の変位を
逆方向としたことを特徴とする変位素子、ならびに、長
さ方向に変位する少なくとも３枚以上の電歪基板を長さ
方向と平行で並列に配置し。Furthermore, a displacement element characterized in that displacements in the longitudinal direction of adjacent piezoelectric substrates when a voltage is applied are in opposite directions, and at least three or more electrostrictive substrates that are displaced in the longitudinal direction parallel to the longitudinal direction. placed in parallel.
かつ隣接する電歪基板を長さ方向の交互に逆の一端で固
定し、さらに並列に配置した電歪基板のうち一つおきの
電歪基板が電圧印加により変位するようにしたことを特
徴とする変位素子を提供する。Adjacent electrostrictive substrates are fixed at opposite ends alternately in the length direction, and further, every other electrostrictive substrate among the electrostrictive substrates arranged in parallel is displaced by application of a voltage. A displacement element is provided.
以下に本発明を実施例により説明する。The present invention will be explained below using examples.
実施例１
第１図は本発明の実施例を示す変位素子の構成図である
。長さ５０ｍｍ、幅５ｍｍ、厚さｏ、ｓｍｍの形状のチ
タン酸ジルコン酸鉛系磁器よりなる圧電基板１ａ、１ｂ
、１ｃ（電極はｃｒ−ムＵ蒸着電極で分極ハ厚み方向）
３枚を図に示すように平行に配置したのち、隣接する圧
電基板１ｉ、１ｂ。Embodiment 1 FIG. 1 is a configuration diagram of a displacement element showing an embodiment of the present invention. Piezoelectric substrates 1a and 1b made of lead zirconate titanate ceramic and having a length of 50 mm, a width of 5 mm, and a thickness of o and s mm.
, 1c (electrode is CR-M U vapor deposited electrode with polarization in thickness direction)
After arranging the three piezoelectric substrates in parallel as shown in the figure, adjacent piezoelectric substrates 1i and 1b are placed.
同１ｂ、１Ｃをその端部で長さ６ｍｍにエポキシ゛お、
その固定は図に示すように互いに逆の一端で固定した。Epoxy the ends of the same 1b and 1C to a length of 6 mm.
The fixing was done at opposite ends as shown in the figure.
また、固定部分の電極は接着前に除去した。その後、自
由端の一つを図のように支持台４に接着剤で固定し、変
位量を測定する際の基準とした。このようにして作製し
た変位素子７の３対の電極５ａ 、５ｂ 、同５０，５
６．同５ｅ、５ｆ間に５００Ｖの直流電圧を隣接する３
枚の圧電基板１ａ、１ｂ、１ａが交互に逆向きの変位を
する方向に、すなわち圧電基板１１Ｌ、１０が伸びると
き圧電基板１ｂが縮み、圧電基板１１Ｌ、１０が縮むと
き圧電基板１ｂが伸びる方向に印加した。その結果、変
位素子７における自由端６の変位量は長さ方向に±２８
μｍであった。一方、上記の変位素子における圧電基板
１枚だけで構成した従来の変位素子では、電圧印加時の
長さ方向の変位量は１９μｍであり１本発明の構成のも
のに比べて著しく小さからた。すなわち２本発明の変位
素子では、従来の変位素子に比べて、変位素子の長さが
同じ状態で、約３倍の変位量が得られた。また、を交互
に逆の端部ですることにより、変位量をより大きくする
ことができる。その変位量は圧電基板に印加する電圧の
増加に比例して、はぼ直線的に大きくなる。印加電圧が
交流であれば、その同波数の伸縮が得られる。なお、実
施例１で圧電基板１ｂに電圧を印加しない場合は変位量
が小さくなるが、それでも従来のものよシは大きい。In addition, the fixed electrode was removed before bonding. Thereafter, one of the free ends was fixed to the support base 4 with an adhesive as shown in the figure, and was used as a reference when measuring the amount of displacement. Three pairs of electrodes 5a, 5b, 50, 5 of the displacement element 7 manufactured in this way
6. A DC voltage of 500V is applied between 5e and 5f of the adjacent 3
The piezoelectric substrates 1a, 1b, 1a are alternately displaced in opposite directions, that is, when the piezoelectric substrates 11L, 10 extend, the piezoelectric substrate 1b contracts, and when the piezoelectric substrates 11L, 10 contract, the piezoelectric substrate 1b extends. was applied to. As a result, the amount of displacement of the free end 6 of the displacement element 7 is ±28 in the length direction.
It was μm. On the other hand, in the conventional displacement element described above, which is composed of only one piezoelectric substrate, the amount of displacement in the longitudinal direction when voltage is applied is 19 μm, which is significantly smaller than that of the structure of the present invention. That is, in the two displacement elements of the present invention, about three times as much displacement as the conventional displacement element was obtained with the same length of the displacement element. Furthermore, by alternately performing the steps at opposite ends, the amount of displacement can be increased. The amount of displacement increases approximately linearly in proportion to an increase in the voltage applied to the piezoelectric substrate. If the applied voltage is alternating current, expansion and contraction of the same wave number can be obtained. Note that in Example 1, when no voltage is applied to the piezoelectric substrate 1b, the amount of displacement becomes smaller, but it is still larger than the conventional one.
なお、実施例では圧電基板として圧電磁器を用いたが、
その池の圧電材料たとえば圧電単結晶。In addition, although piezoelectric ceramic was used as the piezoelectric substrate in the example,
The piezoelectric material of the pond, for example piezoelectric single crystal.
有機圧電材料でもよいことはもちろんである。また、圧
電基板として圧電板を複数枚貼り合わせたものでもよい
。実施例では厚み方向に分極処理した圧電基板を用いた
が、分極が長さ方向で長さ方向に電界を印加して用いて
もよい。Of course, organic piezoelectric materials may also be used. Alternatively, the piezoelectric substrate may be one in which a plurality of piezoelectric plates are bonded together. In the embodiment, a piezoelectric substrate polarized in the thickness direction was used, but the piezoelectric substrate may be polarized in the length direction and an electric field applied in the length direction.
実施例２
第２図は本発明の変位素子の池の実施例を示すものであ
る。３枚の（ＰｂＯ，９”’０．１）（ＭｇＨＮｂ、Ｈ
）０．６９Ｔ ｉ Ｏ，３１０３なる一般式で示される
組成をもつ電歪磁器板８ａ 、８ｂ 、８ｃ（長さ５０
ｍｍ 、幅１０ｍｍ、厚さ０，５ｍ７７Ｌ）の両面の
中央部にそれツレ長さ４０ｍｍ（７）電ｔｉｉ９ａ、９
ｂ、同９ｃ。Embodiment 2 FIG. 2 shows an embodiment of the displacement element pond of the present invention. Three sheets of (PbO, 9'''0.1) (MgHNb, H
)0.69T i O,3103 Electrostrictive porcelain plates 8a, 8b, 8c (length 50
mm, width 10mm, thickness 0.5m77L) with a warp length of 40mm in the center of both sides (7) electric tii9a, 9
b, 9c.
９ｄ、同９ｅ、９ｆ（Ｏｒ−ムＵ蒸着）をつけたのち、
第２図のように電歪磁器板ｓｌ、ｓｂ、ｓｃを配置し、
隣接する基板８ｍ、８ｂ、同８ｂ。After attaching 9d, 9e, and 9f (Or-mu U vapor deposition),
Arrange the electrostrictive porcelain plates sl, sb, and sc as shown in Figure 2,
Adjacent substrates 8m, 8b, 8b.
８Ｃの端部６ｍｍをエポキシｊ！Ｒ脂板１０３．１０ｂ
（５×１０×２ｍｍ３）を介して接着剤でそれぞれ固定
した。固定は図に示すように逆の一端で行なった。その
後、自由端の一つを、支持台１１に幅５ｍｍで接着剤を
用いて固定した。このようにして作成した変位素子１２
の電歪磁器板８ａ、８ｃの電極９ｍ、９ｂ、同９ｅ、９
ｆ間に１ｋＶの直流電圧を印加した。その結果、変位素
子１２の自由端１２ａは支持台の方に３８μｍ移動した
。その後、電歪磁器板８ｂの電極９ｃ 、９６間に１ｋ
Ｖの直流電圧を印加した場合には（電歪磁器板Ｓａ。Epoxy the 6mm end of 8C! R fat plate 103.10b
(5 x 10 x 2 mm3) and fixed with adhesive. Fixation was performed at one opposite end as shown in the figure. Thereafter, one of the free ends was fixed to the support stand 11 with a width of 5 mm using an adhesive. Displacement element 12 created in this way
The electrodes 9m, 9b, 9e, 9 of the electrostrictive porcelain plates 8a, 8c
A DC voltage of 1 kV was applied between f. As a result, the free end 12a of the displacement element 12 was moved 38 μm toward the support base. After that, 1k is placed between the electrodes 9c and 96 of the electrostrictive porcelain plate 8b.
When a DC voltage of V is applied (electrostrictive porcelain plate Sa.
８０には電界を印加しない）、自由端１２！Ｌが支持台
１１とは逆方向に２０μｍ移動した。したがって、自由
端１２＆の移動路Ｍは全体で６８μｍであり、大きな変
位量が得られた。さらに電歪磁くすることができる。捷
だ、印加電圧は交流でもよい。なお、この実施例では電
歪基板として室温付近で犬きｌ電歪効果（２次の効果）
が得られる（Ｐｂｏ、９Ｂａｏ、ｘ）（ＭｇＨＮｂＨ）
、６．Ｔｉｏ、３＋０３磁器を用いたが、 （Ｂａ、
Ｓｒ） ＴｉＯ系磁器。80), free end 12! L moved 20 μm in the opposite direction to the support base 11. Therefore, the total movement path M of the free end 12& was 68 μm, and a large amount of displacement was obtained. Furthermore, it can be made electrostrictive. However, the applied voltage may be alternating current. In addition, in this example, as an electrostrictive substrate, a slight electrostrictive effect (second-order effect) occurs near room temperature.
is obtained (Pbo, 9Bao, x) (MgHNbH)
,6. Tio, 3+03 porcelain was used, (Ba,
Sr) TiO-based porcelain.
磁器などの池の電歪効果の矢きい材料を用いることもで
きる。これらの材料によって得られる変位は２次の効果
であるので、電界の２乗に比例し。It is also possible to use a material that is sensitive to the electrostrictive effect of the pond, such as porcelain. The displacement achieved by these materials is a second-order effect, so it is proportional to the square of the electric field.
印加電圧の正負にはよらない。It does not depend on whether the applied voltage is positive or negative.
なお、本発明で圧電基板あるいは電歪基板の固定部分は
変位に寄与しないので、その部分には電極がなくてよい
。捷だ、圧電基板の場合にはこの部分の分極処理は不必
要である。本発明で、圧電基板あるいは電歪基板は実施
例の矩形板に限られず、円筒状などでもよい。基板の幅
も長さより大きくてもよい。複数の圧電基板あるいは電
歪基板の固定は基板２枚を実施例１のように接着剤で直
接材なってもよいし、実施例２のように樹脂板あ８・−
−ミ゛
るいは金属板、磁器板などを介して行なってもよく、さ
らには金属などのバンドで締めつけたり、ボルト締めな
どでもよい。Note that in the present invention, since the fixed portion of the piezoelectric substrate or the electrostrictive substrate does not contribute to displacement, there may be no electrode in that portion. Fortunately, in the case of a piezoelectric substrate, polarization treatment in this part is unnecessary. In the present invention, the piezoelectric substrate or electrostrictive substrate is not limited to the rectangular plate of the embodiment, but may be cylindrical or the like. The width of the substrate may also be greater than the length. A plurality of piezoelectric substrates or electrostrictive substrates may be fixed by directly bonding two substrates with adhesive as in the first embodiment, or by using resin plates 8-- as in the second embodiment.
- It may be done through a metal plate, a porcelain plate, etc., or it may be tightened with a metal band or bolts.
以上のように１本発明の変位素子では比較的小さな形状
で大きな変位量を得ることができるだめ。As described above, with the displacement element of the present invention, a large amount of displacement can be obtained with a relatively small shape.
ＶＴＲのオートトラッキング用ヘッド駆動素子などに用
いることができる。まだ、本発明の変位素子は変位が直
線的であるとともに、基板の数を増すと、同程度の変位
素子の大きさで著しく変位量を大きくできるため応用範
囲が広い。It can be used as an auto-tracking head drive element of a VTR. Still, the displacement element of the present invention has a wide range of applications because the displacement is linear and by increasing the number of substrates, the amount of displacement can be significantly increased with the same size of displacement element.
第１図と第２図はそれぞれ本発明の実施例の変ξ
位素子斜視図である。
１ａ、１ｂ、１ｃ・・・・・・圧電体、２ｔＬ、２ｂ。
１０＆、１ｏｂ・・・・・・エポキシ４１’：！’１４
１１１・・・・・・支持台、５ ａ 〜５ ｆ 、 ９
ａ 〜９ ｆ・−・−電極、７゜１２・・・・・・変
位素子、ｓａ 、ｓｂ 、ＢＯ・・・・・・電歪磁器板
。
代理人の氏名 弁理士 中 尾 赦 男 ほか１名調
１ 図
１２ 図
、ＱｎFIGS. 1 and 2 are perspective views of ξ position variable elements according to embodiments of the present invention, respectively. 1a, 1b, 1c...Piezoelectric body, 2tL, 2b. 10&, 1ob...Epoxy 41':! '14
111... Support stand, 5 a to 5 f, 9
a to 9 f...-electrode, 7°12...displacement element, sa, sb, BO...electrostrictive porcelain plate. Name of agent: Patent attorney Masao Nakao and one other person
1 Figure 12 Figure, Qn
Claims (3)
と平行で並列に配置し、かつこれらの圧電基板のうち隣
接する圧電基板同士を長さ方向の一端で固定し、さらに
電圧印加時の隣接する圧電基板の変位を逆方向としたこ
とを特徴とする変位素子。(1) A plurality of piezoelectric substrates that are displaced in the length direction are arranged in parallel parallel to the length direction, and adjacent piezoelectric substrates among these piezoelectric substrates are fixed at one end in the length direction, and the voltage A displacement element characterized in that adjacent piezoelectric substrates are displaced in opposite directions when an applied voltage is applied.
電基板のうち隣接する圧電基板同士の固定が交互に逆の
一端でなされたことを特徴とする特許請求の範囲第１項
に記載の変位素子。(2) The device according to claim 1, wherein there are at least three piezoelectric substrates, and adjacent piezoelectric substrates among these piezoelectric substrates are fixed alternately at opposite ends. displacement element.
板を長さ方向と平行で並列に配置し、かつこれら電歪基
板のうち隣接する電歪基板同士を長さ方向の交互に逆の
一端で固定し、さらに並列に配置しだ電歪基板のうち一
つおきの電歪基板が電圧印加により変位するようにした
ことを（４）隣接する電歪基板が電圧印加により交互に
変位するようにしたことを特徴とする特許請求の範囲第
３項記載の変位素子。(3) At least three or more electrostrictive substrates that are displaced in the length direction are arranged in parallel parallel to the length direction, and adjacent electrostrictive substrates among these electrostrictive substrates are alternately reversed in the length direction. (4) Adjacent electrostrictive substrates are alternately displaced by voltage application. The displacement element according to claim 3, characterized in that the displacement element is configured to:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56166234A JPS5867085A (en) | 1981-10-16 | 1981-10-16 | Displacement element |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56166234A JPS5867085A (en) | 1981-10-16 | 1981-10-16 | Displacement element |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5867085A true JPS5867085A (en) | 1983-04-21 |
| JPH039633B2 JPH039633B2 (en) | 1991-02-08 |
Family
ID=15827593
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP56166234A Granted JPS5867085A (en) | 1981-10-16 | 1981-10-16 | Displacement element |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5867085A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01147694U (en) * | 1988-03-31 | 1989-10-12 |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56157649A (en) * | 1980-10-15 | 1981-12-04 | Takata Kk | Driver protecting device by utilization of air belt |
-
1981
- 1981-10-16 JP JP56166234A patent/JPS5867085A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56157649A (en) * | 1980-10-15 | 1981-12-04 | Takata Kk | Driver protecting device by utilization of air belt |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01147694U (en) * | 1988-03-31 | 1989-10-12 | ||
| JPH0721115Y2 (en) * | 1988-03-31 | 1995-05-15 | 本多電子株式会社 | Ultrasonic drive |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH039633B2 (en) | 1991-02-08 |
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