JPH01274673A - Piezoelectric driver - Google Patents
Piezoelectric driverInfo
- Publication number
- JPH01274673A JPH01274673A JP63104651A JP10465188A JPH01274673A JP H01274673 A JPH01274673 A JP H01274673A JP 63104651 A JP63104651 A JP 63104651A JP 10465188 A JP10465188 A JP 10465188A JP H01274673 A JPH01274673 A JP H01274673A
- Authority
- JP
- Japan
- Prior art keywords
- piezoelectric element
- diaphragm
- driving
- laminated piezoelectric
- driving member
- 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.)
- Pending
Links
- 238000005452 bending Methods 0.000 abstract description 6
- 239000013013 elastic material Substances 0.000 abstract 1
- 241000256247 Spodoptera exigua Species 0.000 description 5
- 238000010586 diagram Methods 0.000 description 3
- 230000008602 contraction Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000010363 phase shift Effects 0.000 description 2
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02N—ELECTRIC MACHINES NOT OTHERWISE PROVIDED FOR
- H02N2/00—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction
- H02N2/02—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction producing linear motion, e.g. actuators; Linear positioners ; Linear motors
- H02N2/021—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction producing linear motion, e.g. actuators; Linear positioners ; Linear motors using intermittent driving, e.g. step motors, piezoleg motors
Landscapes
- General Electrical Machinery Utilizing Piezoelectricity, Electrostriction Or Magnetostriction (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
この発明は、圧電素子を用いたリニア型または回転型の
圧電駆動装置に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a linear or rotary piezoelectric drive device using a piezoelectric element.
従来、複数の積層圧電素子を進行方向とこれに直交する
方向に設け、しゃくとり史的に動作させて直線運動させ
る駆動装置は、インチワームとして知られている。Conventionally, a drive device in which a plurality of laminated piezoelectric elements are provided in a traveling direction and a direction perpendicular thereto, and is operated in a horizontal manner to cause linear movement is known as an inchworm.
また、特開昭６２−２７７０７９号に示すように、音さ
形振動子を用いて共振させ、振動子の直交する２面に設
けた圧電素子により振動子の最大振幅点を円運動させて
駆動する圧電駆動装置が提案されている。In addition, as shown in Japanese Patent Application Laid-Open No. 62-277079, a tuning fork-shaped vibrator is used to resonate, and the maximum amplitude point of the vibrator is driven by circular motion using piezoelectric elements provided on two orthogonal surfaces of the vibrator. A piezoelectric drive device has been proposed.
前記インチワームは、極微小動作には適しているが、１
サイクルで６回の積層圧電素子の伸縮動作を必要とする
。そのため、高周波で駆動しても、周波数の１／６の動
作になり、駆動速度を速くすることが難しい。The inchworm is suitable for extremely small operations, but 1
A cycle requires six expansion and contraction operations of the laminated piezoelectric element. Therefore, even when driven at a high frequency, the operation is 1/6 of the frequency, making it difficult to increase the driving speed.
また、インチワームの場合、負荷を引っ張る方向に使用
すると、積層圧電素子に引っ張り方向の力が作用する。Furthermore, in the case of the inchworm, when a load is applied in a pulling direction, a force in the pulling direction acts on the laminated piezoelectric element.
積層圧電素子は、引っ張り方向の荷重に対しては剥がれ
等の問題があって強度が弱い、そのため、一方向にしか
駆動できないという問題点がある。Laminated piezoelectric elements have problems such as peeling when subjected to loads in the tensile direction, and have low strength. Therefore, there is a problem that they can only be driven in one direction.
前記音さ形のものは、水平および垂直の共振を合わせる
必要があり、この共振合わせが困難という問題点がある
。The tuning fork shape has the problem that it is necessary to match the horizontal and vertical resonances, and it is difficult to match the resonances.
この発明の目的は、駆動速度を速くすることができ、か
つ正逆駆動が行える調整の簡単な圧電駆動装置を提供す
ることである。An object of the present invention is to provide an easily adjustable piezoelectric drive device that can increase the drive speed and perform forward and reverse drive.
この発明の圧電駆動装置は、一定方向に移動可能な駆動
部材を設け、く字状に屈曲した振動板を前記駆動部材の
移動方向に沿って配置する。この振動板に圧電素子を設
けて振動板の基端を固定台に固定する。前記駆動部材の
移動方向に進退自在な保持部材を前記振動板の先端に設
ける。前記駆動部材の移動方向に垂直に伸縮して先端が
前記駆動部材に圧接する積層圧電素子を前記保持部材に
設ける。The piezoelectric drive device of the present invention includes a drive member movable in a fixed direction, and a diaphragm bent in a dogleg shape is arranged along the moving direction of the drive member. A piezoelectric element is provided on this diaphragm, and the base end of the diaphragm is fixed to a fixed base. A holding member that can move forward and backward in the direction of movement of the drive member is provided at the tip of the diaphragm. The holding member is provided with a laminated piezoelectric element that expands and contracts perpendicularly to the moving direction of the driving member and has a tip pressed against the driving member.
この発明の構成によると、振動板をく字状としたので、
圧電素子による振動板の屈曲により駆動部材の移動方向
に保持部材を進退駆動できる。この保持部材に設けた積
層圧電素子を振動板の圧電素子の印加電圧と同一の周波
数で伸縮させることにより、積層圧電素子の先端は円状
に移動し、駆動部材が積層圧電素子で摩擦駆動される。According to the configuration of this invention, since the diaphragm has a dogleg shape,
By bending the diaphragm using the piezoelectric element, the holding member can be driven forward and backward in the moving direction of the driving member. By expanding and contracting the laminated piezoelectric element provided on this holding member at the same frequency as the applied voltage to the piezoelectric element of the diaphragm, the tip of the laminated piezoelectric element moves in a circular shape, and the driving member is frictionally driven by the laminated piezoelectric element. Ru.
振動板の圧電素子と積層圧電素子に印加する電圧の位相
のずれを逆方向とすることにより、前記円状運動の方向
が逆となり、駆動部材を逆方向に駆動できる。積層圧電
素子は駆動部材を押圧するものであり、圧縮方向の力の
みが作用する。By setting the phase shift of the voltages applied to the piezoelectric element of the diaphragm and the laminated piezoelectric element in opposite directions, the direction of the circular motion is reversed, and the driving member can be driven in the opposite direction. The laminated piezoelectric element presses the drive member, and only force in the compression direction acts on it.
この発明の一実施例を第１図ないし第５図に基づいて説
明する。この圧電駆動装置は、リニアアクチュエータに
適用した例である。丸棒または角棒状の駆動部材ｌの両
側に２枚の振動板２を配置し、振動板２の基端を固定台
３の支持金具４に固定しである。駆動部材ｌは、固定台
３に対して軸方向移動自在にガイド手段（図示せず）で
支持しである。駆動部材１は、支持金具４と後述の保持
部材６に挿通して移動自在に支持しても良い、振動板２
はエリンバ等の金属弾性材料からなり、長方形に形成し
てく字状に屈曲させである。振動板２の屈曲部よりも基
端側に、圧電素子５が貼り付けてあり、圧電素子５は図
の十−の符号のように分極しである０両振動板２の先端
間にわたり、駆動部材ｌの移動方向にのみ移動自在な板
状の保持部材６を取付ける。保持部材６は適宜のガイド
手段により移動方向を拘束するが、ガイド手段を省いて
も良い、保持部材６には一対の固定金具７を固定し、駆
動部材ｌを挟んで対向する一対の積層圧電素子８を固定
金具７に固定する。積層圧電素子８は、伸縮方向が駆動
部材ｌの軸方向と垂直な方向となるようにする。An embodiment of the present invention will be described based on FIGS. 1 to 5. This piezoelectric drive device is an example applied to a linear actuator. Two diaphragms 2 are arranged on both sides of a driving member l in the shape of a round or square bar, and the base ends of the diaphragms 2 are fixed to a support fitting 4 of a fixed base 3. The driving member 1 is supported by guide means (not shown) so as to be movable in the axial direction relative to the fixed base 3. The driving member 1 includes a diaphragm 2 which may be movably supported by being inserted into a support fitting 4 and a holding member 6 (described later).
is made of an elastic metal material such as Erinba, and is formed into a rectangle and bent into a dogleg shape. A piezoelectric element 5 is pasted on the proximal side of the diaphragm 2 from the bending part, and the piezoelectric element 5 is polarized as shown in the figure. A plate-shaped holding member 6 that is movable only in the moving direction of the member 1 is attached. The movement direction of the holding member 6 is restrained by appropriate guide means, but the guide means may be omitted. A pair of fixing fittings 7 are fixed to the holding member 6, and a pair of laminated piezoelectric elements facing each other with the driving member l in between is fixed to the holding member 6. The element 8 is fixed to the fixture 7. The laminated piezoelectric element 8 is arranged so that its expansion and contraction direction is perpendicular to the axial direction of the drive member l.
第５図に示すように、一対の圧電素子５には高周波ｉｔ
源１２から同じ位相の高周波電圧を印加する。この高周
波電圧を移相回路１０により９０゜位相をずらせ、その
出力に同期をとってパルス駆動回路９からパルス電圧を
積層圧電素子８に印加する。１１はパルス駆動回路９の
直流電源である。As shown in FIG. 5, the pair of piezoelectric elements 5 are
A high frequency voltage of the same phase is applied from a source 12. The phase of this high frequency voltage is shifted by 90 degrees by a phase shift circuit 10, and a pulse voltage is applied to the laminated piezoelectric element 8 from a pulse drive circuit 9 in synchronization with the output thereof. Reference numeral 11 denotes a DC power supply for the pulse drive circuit 9.
なお、積層圧電素子８を電歪材料で構成した場合は、一
方向のパルス電圧を印加し、伸びと原形復帰で伸縮させ
る。圧電材料の場合は、印加電圧の極性によって伸縮す
るので、積層圧電素子８を駆動部材１に接触させて配置
し、逆極性の電圧で離れるようにする。Note that when the laminated piezoelectric element 8 is made of an electrostrictive material, a unidirectional pulse voltage is applied to cause it to expand and contract by stretching and returning to its original shape. In the case of a piezoelectric material, it expands and contracts depending on the polarity of the applied voltage, so the laminated piezoelectric element 8 is placed in contact with the drive member 1 and separated by a voltage of opposite polarity.
動作を説明する。振動板２の圧電素子５に高周波電圧を
印加して励振すると、振動板２は屈曲ししてその先端の
保持部材６が積層圧電素子８とともに駆動部材ｌの軸方
向に進退する。この時、積層圧電素子８に、前記印加電
圧に対して９０°位相の遅れた同一周波数のパルス直流
電圧（第３図（Ｂ））を印加すると、第４図（Ａ）〜（
Ｃ）に示すように、積層圧電素子９の先端部は円状運動
する。そのため、駆動部材ｌは積層圧電素子８で摩擦駆
動され、軸方向に駆動される。積層圧電素子８に印加す
るパルス電圧を９０°進んだ位相（第３図（Ｃ）とする
と、積層圧電素子８の回転方向は前記と逆となり、駆動
部材ｌは逆方向に駆動される。Explain the operation. When a high frequency voltage is applied to the piezoelectric element 5 of the diaphragm 2 to excite it, the diaphragm 2 is bent and the holding member 6 at the tip moves forward and backward together with the laminated piezoelectric element 8 in the axial direction of the drive member l. At this time, when a pulsed DC voltage of the same frequency (FIG. 3(B)) whose phase is delayed by 90 degrees with respect to the applied voltage is applied to the laminated piezoelectric element 8, as shown in FIGS.
As shown in C), the tip of the laminated piezoelectric element 9 moves in a circular manner. Therefore, the drive member l is frictionally driven by the laminated piezoelectric element 8 and driven in the axial direction. If the phase of the pulse voltage applied to the laminated piezoelectric element 8 is advanced by 90 degrees (FIG. 3(C)), the rotation direction of the laminated piezoelectric element 8 will be opposite to that described above, and the driving member l will be driven in the opposite direction.
このように動作を行うが、く字状の振動板ｌを圧電素子
５で屈曲させて駆動部材ｌの移動方向の力を得るように
し、積層圧電素子８で駆動部材１に圧接させるので、駆
動部材ｌの送りのサイクルが圧電素子５および積層圧電
素子８の印加電圧と同じ周波数となる。そのため、従来
のインチワームに比べて、駆動部材ｌを高速駆動できる
。Although the operation is performed in this way, the dogleg-shaped diaphragm l is bent by the piezoelectric element 5 to obtain force in the moving direction of the driving member l, and the laminated piezoelectric element 8 is brought into pressure contact with the driving member 1, so that the driving The cycle of feeding the member l has the same frequency as the voltage applied to the piezoelectric element 5 and the laminated piezoelectric element 8. Therefore, the driving member 1 can be driven at a higher speed than the conventional inchworm.
振動板２は２枚を対向して設けであるので、共振して屈
曲振動する。そのため、大きな振幅が得られ、より一層
高速駆動が行える。この場合に、く字状の振動板２を共
振させるので、共振により得られた大きな振幅を駆動部
材移動方向の力に有効に変換できる。共振させるには、
２枚の振動板ｌの共振を合わせ、積層圧電素子８をその
周波数で駆動してやれば良い、これにより効率の良い駆
動が行える。そのため、従来の音さ形のもののように縦
横の共振を合わせる必要があるものに比べて、共振合わ
せが容易である。Since two diaphragms 2 are provided facing each other, they resonate and flexurally vibrate. Therefore, a large amplitude can be obtained and even higher speed driving can be performed. In this case, since the dogleg-shaped diaphragm 2 is caused to resonate, the large amplitude obtained by resonance can be effectively converted into a force in the direction of movement of the driving member. To make it resonate,
It is sufficient to match the resonance of the two diaphragms 1 and drive the laminated piezoelectric element 8 at that frequency, thereby achieving efficient driving. Therefore, resonance adjustment is easier than with conventional tuning fork-shaped devices that require vertical and horizontal resonances to be adjusted.
さらに、振動板５の屈曲で駆動部材ｌの駆動力を得るの
で、駆動部材ｌを正逆いずれの方向に駆動する場合も、
積層圧電素子８には圧縮力のみが作用し、引っ張り強度
を必要としない。Furthermore, since the driving force of the driving member l is obtained by bending the diaphragm 5, when driving the driving member l in either the forward or reverse direction,
Only compressive force acts on the laminated piezoelectric element 8, and tensile strength is not required.
また、２枚の振動板２は屈曲振動させるものであるため
、基端が振動の節となる。そのため、基端で固定するこ
とができて固定構造が容易である。Further, since the two diaphragms 2 are subjected to bending vibration, the base ends become nodes of vibration. Therefore, it can be fixed at the proximal end and the fixing structure is easy.
なお、前記実施例では振動板２を外側に屈曲させたが、
内側すなわち駆動部材１側に屈曲したく字形としても良
い、また、振動板２は、２枚のく字状部分を基端または
先端で一体に連続させたコ字状としても良く、さらにコ
字状の先端に別の弾性体を取付けても良い、振動板２を
１枚だけとしても良い。In addition, although the diaphragm 2 was bent outward in the above embodiment,
The diaphragm 2 may have a dogleg shape bent inward, that is, toward the drive member 1. The diaphragm 2 may also have a U-shape in which two doglegged portions are integrally connected at the base end or the tip. Another elastic body may be attached to the tip of the diaphragm 2, or only one diaphragm 2 may be used.
振動板２の圧電素子５は、前記実施例のように振動板２
の屈曲部よりも基端例の外側面に貼着することが望まし
いが、先端側に貼着しても良く、また振動板の内側面に
貼着してもよい。The piezoelectric element 5 of the diaphragm 2 is connected to the diaphragm 2 as in the above embodiment.
It is preferable to attach it to the outer surface of the proximal end than to the bent part of the diaphragm, but it may also be attached to the distal end side or to the inner surface of the diaphragm.
また、前記実施例はリニア型に適用した場合について説
明したが、駆動部材ｌを回転自在とした回転型の駆動装
置とすることもできる。Furthermore, although the above embodiments have been described with reference to a linear type drive device, it is also possible to use a rotary type drive device in which the drive member 1 is rotatable.
（発明の効果〕
この発明の圧電駆動装置は、く字形の振動板を圧電素子
で屈曲させて駆動部材の移動方向の力を得るようにし、
積層圧電素子で駆動部材に接触させるので、駆動部材の
送りのサイクルが圧電素子および積層圧電素子の印加電
圧と同じ周波数となる。そのため、従来のインチワーム
に比べて、駆動部材を高速駆動できる。また、振動板で
保持部材を駆動部材の移動方向に移動させ、保持部材に
設けた積層圧電素子で圧接力を得るものであるため、従
来の音さ形のものと異なり、縦横の共振合わせのような
複雑な調節が不要である。さらに、振動板の屈曲で駆動
部材の駆動力を得るので、駆動部材を正逆に駆動でき、
しかも積層圧電素子には圧縮力のみが作用し、引っ張り
強度を必要としないという効果がある。(Effects of the Invention) The piezoelectric drive device of the present invention bends the dogleg-shaped diaphragm with a piezoelectric element to obtain force in the direction of movement of the drive member,
Since the laminated piezoelectric element is brought into contact with the driving member, the cycle of feeding the driving member has the same frequency as the piezoelectric element and the voltage applied to the laminated piezoelectric element. Therefore, the driving member can be driven at a higher speed than the conventional inchworm. In addition, since the holding member is moved in the direction of movement of the driving member using the diaphragm and the pressure contact force is obtained by the laminated piezoelectric element provided on the holding member, unlike the conventional tuning fork type, it is possible to align vertical and horizontal resonances. There is no need for such complicated adjustments. Furthermore, since the driving force of the driving member is obtained by bending the diaphragm, the driving member can be driven in forward and reverse directions.
Moreover, only compressive force acts on the laminated piezoelectric element, and there is no need for tensile strength.
第１図はこの発明の一実施例の破断正面図、第２図はそ
の破断平面図、第３図は同じくその印加電圧の波形図、
第４図は同じくその動作説明図、第５図は同じくその駆
動回路のブロック図である。
１・・・駆動部材、２・・・振動板、３・・・固定台、
４・・・支持金具、５・・・圧電素子、６・・・保持部
材、８・・・積層圧電素子
第１ｒ！！：Ｊ
３１ｉ２ 図
第４図FIG. 1 is a cutaway front view of an embodiment of the present invention, FIG. 2 is a cutaway plan view thereof, and FIG. 3 is a waveform diagram of the applied voltage.
FIG. 4 is an explanatory diagram of its operation, and FIG. 5 is a block diagram of its driving circuit. 1... Drive member, 2... Vibration plate, 3... Fixed base,
4... Support metal fitting, 5... Piezoelectric element, 6... Holding member, 8... Laminated piezoelectric element 1st r! ! :J 31i2 Figure 4
Claims (1)
した振動板を前記駆動部材の移動方向に沿って配置し、
この振動板に圧電素子を設けて振動板の基端を固定台に
固定し、前記駆動部材の移動方向に進退自在な保持部材
を前記振動板の先端に設け、前記駆動部材の移動方向に
垂直に伸縮して先端が前記駆動部材に圧接する積層圧電
素子を前記保持部材に設けた圧電駆動装置。A driving member movable in a certain direction is provided, and a diaphragm bent in a dogleg shape is arranged along the moving direction of the driving member,
A piezoelectric element is provided on the diaphragm to fix the base end of the diaphragm to a fixed base, and a holding member that can move forward and backward in the direction of movement of the driving member is provided at the tip of the diaphragm, perpendicular to the direction of movement of the driving member. A piezoelectric drive device, wherein the holding member is provided with a laminated piezoelectric element that expands and contracts and has a tip pressed against the drive member.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63104651A JPH01274673A (en) | 1988-04-25 | 1988-04-25 | Piezoelectric driver |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63104651A JPH01274673A (en) | 1988-04-25 | 1988-04-25 | Piezoelectric driver |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01274673A true JPH01274673A (en) | 1989-11-02 |
Family
ID=14386362
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63104651A Pending JPH01274673A (en) | 1988-04-25 | 1988-04-25 | Piezoelectric driver |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01274673A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006141091A (en) * | 2004-11-10 | 2006-06-01 | Shimizu Corp | Ultrasonic motor and variable rigidity spring |
| WO2007093074A2 (en) * | 2006-02-16 | 2007-08-23 | Nanoswys Sa | Force converter |
| WO2019032790A1 (en) * | 2017-08-11 | 2019-02-14 | Caprice Gray Haley | Wire handling apparatus |
| CN111223635A (en) * | 2018-11-27 | 2020-06-02 | 株式会社碧陆斯 | Voltage transformation device |
-
1988
- 1988-04-25 JP JP63104651A patent/JPH01274673A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006141091A (en) * | 2004-11-10 | 2006-06-01 | Shimizu Corp | Ultrasonic motor and variable rigidity spring |
| JP4573102B2 (en) * | 2004-11-10 | 2010-11-04 | 清水建設株式会社 | Ultrasonic motor and variable stiffness spring |
| WO2007093074A2 (en) * | 2006-02-16 | 2007-08-23 | Nanoswys Sa | Force converter |
| WO2007093074A3 (en) * | 2006-02-16 | 2008-01-24 | Nanoswys Sa | Force converter |
| WO2019032790A1 (en) * | 2017-08-11 | 2019-02-14 | Caprice Gray Haley | Wire handling apparatus |
| CN111223635A (en) * | 2018-11-27 | 2020-06-02 | 株式会社碧陆斯 | Voltage transformation device |
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