WO2012070178A1

WO2012070178A1 - Electromechanical conversion element and drive apparatus using same

Info

Publication number: WO2012070178A1
Application number: PCT/JP2011/005617
Authority: WO
Inventors: 浩久末吉; 柴谷　一弘; 秦　良彰; 義弘佐伯; 琢哉村田
Original assignee: コニカミノルタオプト株式会社
Priority date: 2010-11-22
Filing date: 2011-10-05
Publication date: 2012-05-31

Abstract

The electromechanical conversion element (1A) according to this invention converts electrical energy into mechanical energy, and has an electrode pair (11d-1, 11d-2) formed on a given surface in order to supply the electrical energy, and first through third insulating layers (12, 13, 14) as a form of short circuit prevention unit to prevent a short circuit to a given member should contact be made with the member. Accordingly, even in the event that this kind of electromechanical conversion element (1A) is heated, a short circuit can be prevented to a given member that comes into contact with the electromechanical conversion element (1A).

Description

Electromechanical transducer and drive device using the same

The present invention relates to an electromechanical conversion element that converts electrical energy into mechanical energy and a drive device using the electromechanical conversion element.

In a mechanical device including a movable part, an actuator is usually incorporated to drive the movable part. This actuator is a device that converts input energy into mechanical momentum, one of which is referred to as SIDM (Smooth Impact Drive Mechanism, “SIDM” is a registered trademark), for example, an electromechanical transducer such as a piezoelectric element. A driving device using an element is known.

This SIDM device is usually an electromechanical conversion element that converts electrical energy into mechanical energy, a drive member that is fixed to one end of the electromechanical conversion element, transmits the mechanical energy, and has a predetermined friction on the drive member. A moving member engaged by force and a fixing member that is fixed to and supports a predetermined support such as a housing or a frame are provided. The electromechanical transducer is, for example, a piezoelectric element in which a plurality of piezoelectric layers made of a piezoelectric material are stacked via internal electrodes between each piezoelectric layer. A pair of external electrodes for supplying the electric energy is respectively formed on a pair of side surfaces facing each other along the stacking direction of the piezoelectric elements, and the pair of external electrodes is connected to the plurality of internal electrodes. They are connected alternately one after another. In the SIDM device having such a configuration, when a pulsed drive voltage is applied from an external drive circuit via the pair of external electrodes, the piezoelectric element expands and contracts in the stacking direction. The drive member reciprocates in the longitudinal direction according to the expansion and contraction of the piezoelectric element. Here, when the electromechanical conversion element (here, the piezoelectric element) is repeatedly expanded and contracted so that the moving speed of the driving member is asymmetric between the forward path and the backward path, the moving member is moved by the asymmetric reciprocating motion of the driving member. It moves along the said longitudinal direction, and an electrical energy is converted into the motion of a moving member (for example, refer patent document 1).

One of such SIDM devices is a device called an LVA method, which is disclosed in, for example, Patent Document 2.

FIG. 7 is a perspective view showing the configuration of the piezoelectric actuator disclosed in Patent Document 2. FIG. As shown in FIG. 7, the LVA type SIDM apparatus 1000 includes a rectangular columnar piezoelectric element 1001 that expands and contracts along a predetermined axial direction (Y-axis direction in FIG. 7) and one of the piezoelectric elements 1001 in the Y-axis direction. A drive shaft 1002 that is eccentrically fixed to the end face and is displaced in the Y-axis direction by expansion and contraction of the piezoelectric element 1001, and a support member 1003 that supports the piezoelectric element 1001 and the drive shaft 1002 are provided. In such an LVA type SIDM apparatus 1000, the drive shaft 1002 performs a so-called swinging motion when the piezoelectric element 1001 is expanded and contracted. This swinging motion can be used, for example, for optical axis alignment in an XZ plane of an optical element (not shown) attached to a moving body (not shown) that frictionally engages with the drive shaft 1002. Note that the moving body can also move in the Y-axis direction.

For example, in the above-mentioned SIDM device as disclosed in Patent Document 1, the fixing member is fixed to the other end of the electromechanical transducer, but in the LVA type SIDM device, the supporting member 1003 ( The fixing member) is configured to fix and support the driving member 1002 with a fixing portion 1004. In addition, the LVA type SIDM apparatus includes an apparatus configured to fix and support the vicinity of a connection portion between the drive member (drive shaft) and the electromechanical transducer. For the fixing, a thermosetting adhesive is usually used in order to obtain a sufficient adhesive strength. For this reason, the fixing member is made of a metal such as stainless steel for heat resistance during the thermosetting. Material is used.

Incidentally, in an electromechanical conversion element such as a piezoelectric element, when a so-called thermal shock is applied, an electric charge may be generated in the electromechanical conversion element due to deformation due to thermal expansion of the electromechanical conversion element. When this charge is accumulated, the positive and negative polarities change, and as a result, the electromechanical conversion element may not perform a desired operation. For this reason, in order to discharge such charges from the electromechanical conversion element to the outside, the electromechanical conversion element includes a discharge of the charge on a surface different from the predetermined surface on which the pair of electrode portions are formed. For example, a conductive portion having a predetermined electric resistance value of about 10 kΩ to 10 MΩ is formed.

When the electromechanical conversion element including such a conductive portion is heated in the manufacturing process, for example, when heated to, for example, about 150 ° C. in an adhesive fixing process in which the thermosetting adhesive is bonded and fixed, By heating, the resistance value of the conductive portion is reduced from the predetermined resistance value to, for example, about 500Ω. As a result, the electromechanical conversion element and a predetermined member connected to the electromechanical conversion element, in the above-described example, may be short-circuited, which may cause a disadvantage that the electromechanical conversion element does not operate.

Although a countermeasure for forming the fixing member with an insulating material such as a resin may be considered, a material that does not deform at the thermosetting temperature and has sufficient adhesive strength has not yet been found, and avoid the heating. For this purpose, for example, a measure of bonding with an adhesive such as an ultraviolet curable adhesive may be considered, but an adhesive having sufficient adhesive strength has not yet been found.

JP 2002-95274 A JP 2010-98932 A

The present invention has been made in view of the above-described circumstances, and an object thereof is an electromechanical conversion capable of preventing a short circuit with a predetermined member connected to the electromechanical conversion element even when heated. It is to provide an element. And this invention is providing the drive device using this electromechanical transducer.

An electromechanical transducer according to the present invention is an electromechanical transducer that converts electrical energy into mechanical energy, is formed on a predetermined surface, and has a pair of electrode portions for supplying the electrical energy, A short-circuit prevention unit for preventing a short circuit with the member when connected to the member. Therefore, even when such an electromechanical conversion element is heated, a short circuit with a predetermined member connected to the electromechanical conversion element can be prevented.

The above and other objects, features and advantages of the present invention will become apparent from the following detailed description and the accompanying drawings.

It is a figure which shows the structure of the optical element drive device concerning 1st Embodiment. It is a figure which shows the structure of the electromechanical conversion element in the optical element drive device shown in FIG. It is a figure which shows the structure of the part of the electromechanical conversion element in the optical element drive device shown in FIG. 1, a drive member, and a fixing member. It is a disassembled perspective view of the part of the electromechanical conversion element in the optical element drive device shown in FIG. 1, a drive member, and a fixing member. It is a figure which shows the other structure of the electromechanical conversion element in the optical element drive device shown in FIG. It is a figure which shows the structure of the optical element drive device concerning 2nd Embodiment. 10 is a perspective view illustrating a configuration of a piezoelectric actuator disclosed in Patent Document 2. FIG.

Hereinafter, an embodiment according to the present invention will be described with reference to the drawings. In addition, the structure which attached | subjected the same code | symbol in each figure shows that it is the same structure, The description is abbreviate | omitted suitably.

(First embodiment)
FIG. 1 is a diagram illustrating a configuration of an optical element driving device according to the first embodiment. FIG. 2 is a diagram illustrating a configuration of an electromechanical transducer in the optical element driving device illustrated in FIG. In the center of FIG. 2, the entire electromechanical conversion element 1 A is shown, the right side thereof shows the right side of the side surface, the left side shows the left side of the side surface, and the lower side shows The front of the side is shown. Note that the rear surface of the side surface is the same as the front surface, and the illustration thereof is omitted. FIG. 3 is a diagram illustrating a configuration of the electromechanical conversion element, the driving member, and the fixing member in the optical element driving apparatus illustrated in FIG. 1. FIG. 4 is an exploded perspective view of the electromechanical conversion element, the driving member, and the fixing member in the optical element driving apparatus shown in FIG.

In FIG. 1, an optical element driving device DA is moved (displaced) by a driving device 10 including an electromechanical conversion element 1A, a driving member 2, a fixing member 3 and a moving member 4, a support member SA, and the driving device 10. And an optical element L as a driven body.

The support member SA is a member that supports the drive device 10, and is, for example, a housing or a frame. When the fixing member 3 of the drive device 10 is fixed to the support member SA, the drive device 10 is supported by the support member SA. For example, adhesive fixing with an adhesive is used for fixing the support member SA and the fixing member 3. Also, for example, other methods such as screwing or brazing may be used.

The optical element L is an example of a driven body that is moved (displaced) by the driving device 10, and is, for example, a device such as a lens, an optical fiber, or a light source. The optical element L is fixed to and supported by the moving member 4. The optical element L is thus provided on the moving member 4, and thus the optical element L moves in accordance with the movement of the moving member 4.

The driving device 10 includes an electromechanical conversion element 1A, a driving member 2, a fixed member 3, and a moving member 4.

The electromechanical conversion element 1A is an element that converts input electrical energy into mechanical energy, that is, mechanical motion. For example, the piezoelectric element 1A that converts input electrical energy into mechanical expansion and contraction motion by the piezoelectric effect, etc. It is.

The piezoelectric element 1A as the electromechanical conversion element 1A includes, for example, as shown in FIG. 2, a laminate 11, a pair of external electrode portions 11d (11d-1, 11d-2), and a conductive portion 11e (11e- 1, 11e-2).

In addition, in this specification, when referring generically, it shows with the reference symbol which abbreviate | omitted the suffix, and when referring to an individual structure, it shows with the reference symbol which attached the suffix.

The laminated body 11 is formed by alternately laminating a plurality of thin film (layered) piezoelectric layers 11a made of a piezoelectric material and conductive thin film (layered) internal electrode layers 11b and 11c. In the present embodiment, the stacked body 11 has a quadrangular prism shape. Each of the internal electrode layers 11b and 11c is formed so that one end (one edge) thereof faces the outside. More specifically, the internal electrode layer 11b is formed so that one end thereof faces a predetermined side surface of the multilayer body 11, in the example shown in FIG. 2, the left side surface, and the internal electrode 11c has one end thereof. The part is formed so as to face the side surface facing the predetermined side surface of the laminated body 11, in the example shown in FIG. As described above, each of the internal electrode layers 11b and 11c is configured to face the outside with a pair of outer peripheral side surfaces facing each other. Examples of the piezoelectric material include so-called PZT, crystal, lithium niobate (LiNbO ₃ ), potassium niobate tantalate (K (Ta, Nb) O ₃ ), barium titanate (BaTiO ₃ ), lithium tantalate (LiTaO ₃ ). And inorganic piezoelectric materials such as strontium titanate (SrTiO ₃ ).

The pair of external electrode portions 11 d (11 d-1, 11 d-2) is formed on a predetermined surface on the outer peripheral surface of the multilayer body 11, and supplies the electric energy to the multilayer body 11. More specifically, one first external electrode portion 11d-1 of the pair of external electrode portions 11d is provided on the left side surface so as to be electrically connected to the internal electrode layer 11b in the example shown in FIG. In this example, the other second external electrode portion 11d-2 is formed in a thin film shape (layer shape) along the stacking direction, and in this example, the stacking direction is formed on the right side surface so as to be electrically connected to the internal electrode layer 11c. Are formed in a thin film shape (layer shape). In this way, the pair of external electrodes 11 d-1 and 11 d-2 are sequentially conducted alternately with the internal electrode layers 11 b and 11 c, and supplies the electric energy to each piezoelectric layer 11 a of the multilayer body 11. These external electrode portions 11d-1 and 11d-2 are made of, for example, conductive conductive materials such as gold, silver, copper, or the like, which are conductive by dispersing metal fillers or the like, for example, by sputtering or vapor deposition. It is formed in a thin film shape along the laminating direction on a pair of outer peripheral side surfaces facing each other in the laminate 11 by screen printing of the resin.

The conductive portion 11e is formed on a predetermined surface on the outer peripheral surface of the multilayer body 11 different from the predetermined surface on which the pair of electrode portions 11d-1 and 11d-2 is formed, and has conductivity. . In the example shown in FIG. 2, the conductive portion 11e includes conductive portions 11e-1 and 11e-2 formed in a thin film shape (layer shape) on each of the front side surface and the back side surface. The conductive portion 11e-2 formed on the back side surface facing the front side surface is not shown in FIG. The conductive portion 11e is provided in the piezoelectric element 1A, for example, in order to discharge the electric charge generated when a so-called thermal shock is applied to the piezoelectric element 1A, and is a predetermined suitable for discharging the electric charge. For example, a conductive resin having conductivity in which a metal filler or the like is dispersed is formed so as to have an electrical resistance value of, for example, about 10 kΩ to 10 MΩ.

In the piezoelectric element 1A as an example of the electromechanical conversion element 1A having such a configuration, a predetermined voltage is applied to the pair of external electrode portions 11d-1 and 11d-2 from an external circuit such as a drive control circuit, for example. When electric energy is supplied to each piezoelectric layer 11a of the stacked body 11, the stacked body 11 extends or contracts in the stacking direction due to the piezoelectric effect of each piezoelectric layer 11a.

And in this embodiment, 1 A of piezoelectric elements are further equipped with the short circuit prevention part for preventing a short circuit with the said member, when connecting to a predetermined member. In the example shown in FIGS. 1 and 2, in order to prevent a short circuit with the fixing member 3 when being fixed to the fixing member 3, a pair of first and second insulating materials is used as an example of a short-circuit prevention unit. Insulation protection layers 12 and 13 are formed on the pair of external electrode portions 11d-1 and 11d-2, respectively. As an example of the short-circuit prevention portion, an insulating third insulation protection layer 14 is provided with the conductive layer. It is formed over substantially the entire surface of the portion 11e. In the present embodiment, the third insulating protective layer 14 is formed on each of the pair of conductive portions 11e-1 and 11e-2. The first to third insulating protective layers 12 to 14 are formed in a thin film shape (layer shape) with an insulating resin, for example. The third insulating protective layer 14 electrically insulates and protects the conductive portion 11e from the outside over substantially the entire surface.

The first insulating protective layer 12 is formed over the entire surface of the external electrode portion 11d-1 except for the first opening 12a for exposing the external electrode portion 11d-1 to the outside. Is formed over the entire surface of the external electrode portion 11d-1 excluding the second opening 13a for exposing the external electrode portion 11d-2 to the outside. That is, the first insulating protection layer 12 is formed with an elliptical first opening 12a reaching the external electrode portion 11d-1, and the external electrode portion 11d-1 covers the region of the first opening 12a. The second insulating protective layer 13 is covered with an ellipsoidal second opening 13a that reaches the external electrode portion 11d-2, and the external electrode portion 11d-2 is covered with the first insulating protective layer 12. The second insulating protective layer 13 is covered except for the region of the second opening 13a. Thus, the first insulating protective layer 12 electrically insulates and protects the external electrode portion 11d-1 from the outside except for the region of the first opening 12a, and the second insulating protective layer 13 Except for the region of the opening 13a, the external electrode portion 11d-2 is electrically insulated and protected from the outside.

The first and second insulating

protective layers

12 and 13 are configured to have different shapes in plan view. In the present embodiment, by forming a mark on at least one of the first and second insulating

protective layers

12 and 13, the first and second insulating

protective layers

12 and 13 have different shapes in plan view. It is configured. For example, as shown in FIG. 2, the second insulating protective layer 13 is provided with a mark 13b having a predetermined shape, in this example, an elliptical shape. The mark 13b may be formed, for example, by sticking a seal with a predetermined shape, or may be formed, for example, by painting a paint with a predetermined shape. Or in order to reduce a process, it is the opening part similar to the 2nd opening part 13a, Comprising: You may form simultaneously with the 2nd opening part 13a. The mark may be provided on the first insulating protective layer 12, or may be provided on the first and second insulating

protective layers

12 and 13, for example, by having different shapes.

The driving member 2 is a member that is fixed to the piezoelectric element 1A as the electromechanical conversion element 1A and that transmits mechanical energy converted from electric energy by the piezoelectric element 1A. More specifically, in this embodiment, the drive member 2 is a columnar (axial) member fixed to one end of the multilayer body 11 in the piezoelectric element 1A. For this fixing, for example, an adhesive such as a thermosetting adhesive is used. As the material of the drive member 2, for example, any material such as metal, resin, and carbon can be used. The cross section orthogonal to the longitudinal direction of the drive member 2 may be any shape such as a rectangle, a polygon, an ellipse, and a circle, for example, but in the present embodiment, the moving member 4 extends along the longitudinal direction of the drive member 2. The cross section is a chamfered rectangle so that it can be relatively moved.

The fixing member 3 is a member that supports the piezoelectric element 1A and the driving member 2 by holding them. As shown in FIGS. 3 and 4, the fixing member 3 is formed in a substantially U shape (substantially C shape, substantially U shape). The piezoelectric element 1 A and the driving member 2 are supported by the fixing member 3 by fitting the connecting portion between the piezoelectric element 1 A and the driving member 2 into the concave portion in the substantially U shape. More specifically, the connecting portion between the piezoelectric element 1A and the drive member 2 has three peripheral surfaces, excluding one surface (a surface relatively positioned in the positive direction of the x-axis on the peripheral surface). The surface is in contact with the fixing member 3 at a surface (a surface relatively positioned in the negative x-axis direction and each surface positioned in both positive and negative z-axis directions). When the connection portion is fitted, a thermosetting adhesive is applied to the outer peripheral surface of the connection portion between the piezoelectric element 1A and the driving member 2 or the inner peripheral surface of the concave portion of the fixing member 3, and the heating step is performed. As a result, the adhesive is thermally cured, and as a result, the piezoelectric element 1A and the driving member 2 are bonded and fixed to the fixing member 3. In the example shown in FIGS. 3 and 4, the piezoelectric element 1 A and the drive member 2 are connected to the fixing member 3 and fixed at the connection portion, but the driving member 2 is connected to the fixing member 3. The piezoelectric element 1A may be connected to the fixing member 3 and fixed. And the fixing member 3 is being fixed to support member SA by the back surface which opposes the recessed part in the said substantially U shape.

Since the fixing member 3 substantially holds the position in this way, when the stacked body 11 of the piezoelectric elements 1A expands and contracts as described above, the expansion and contraction is transmitted to the driving member 2, and the driving member 2 moves in the piezoelectric element 1A. It reciprocates in conjunction with the expansion and contraction of the laminate 11.

When performing a so-called swing motion (movement in a plane orthogonal to the expansion / contraction direction, movement in the xz plane in FIG. 1), the driving member 2 is connected to the central axis of the piezoelectric element 1A and the driving member. The center axis of 2 is shifted (eccentric) and fixed to the piezoelectric element 1A. For example, the driving member 2 has a length of about 20 to 50% of the diameter of the maximum circumscribed circle on the surface of the piezoelectric element 1A to which the driving member 2 is fixed in the positive x-axis direction with respect to the central axis of the piezoelectric element 1A. Thus, it is fixed to the piezoelectric element 1A so that its central axis is shifted. As described above, the piezoelectric element 1A and the driving member 2 are fixed with their central axes shifted from each other, and the connecting portion between the piezoelectric element 1A and the driving member 2 is asymmetrically bonded and fixed to the fixing member 3. Thus, when the stacked body 11 of the piezoelectric elements 1A expands and contracts, the drive member 2 swings in the x-axis direction. Instead of or in addition to shifting the central axis of the piezoelectric element 1A and the central axis of the driving member 2, the central axis of the driving member 2 and the central axis of the recess (fixed portion) of the fixing member 3 are It may be shifted. Further, the eccentric direction is not limited to the x-axis direction, and may be another direction in the xz plane such as the z-axis direction. Furthermore, the outer peripheral surface of the connecting portion where the connecting portion between the piezoelectric element 1A and the driving member 2 is bonded and fixed to the fixing member 3 is not limited to the three surfaces but may be another surface.

The moving member 4 is a member engaged with the driving member 2 with a predetermined frictional force so as to be relatively movable, and slides with respect to the driving member 2. The moving member 4 is a cylindrical body having a through-hole having a shape corresponding to the outer shape of the driving member 2. By inserting the driving member 2 into the through-hole, the moving member 4 has a predetermined friction so as to be movable relative to the driving member 2. Engage with force. The outer shape of the moving member 4 may be a predetermined shape. An optical element L is fixed to the outer peripheral surface of the moving member 4.

In such an optical element driving device DA, first, when a predetermined voltage is applied to the pair of external electrode portions 11d-1 and 11d-2 from the outside, the piezoelectric element 1A expands and contracts, and in conjunction with the expansion and contraction operation. The drive member 2 reciprocates. The reciprocating motion of the driving member 2 causes the moving member 4 to move along the longitudinal direction of the driving member 2 (in the example shown in FIG. 1, the y direction shown in FIG. 1). More specifically, when the piezoelectric element 1 A extends or contracts relatively slowly, the driving member 2 also moves slowly, and the moving member 4 moves together with the driving member 2 while being frictionally engaged with the driving member 2. On the other hand, when the piezoelectric element 1A contracts or expands relatively steeply, the driving member 2 also moves steeply, and the moving member 4 slides relative to the driving member 2 in an attempt to stay in place by its inertial mass. To do. Such an operation is performed by, for example, inputting a sawtooth waveform voltage to the piezoelectric element 1A to cause asymmetric vibration in the driving member 2, or inputting a rectangular waveform pulse voltage to the piezoelectric element 1A. The drive member 2 is caused to asymmetrically vibrate with the frequency characteristics of the piezoelectric element 1A. In the case of eccentricity as described above, when the stacked body 11 of the piezoelectric elements 1A further expands and contracts, the drive member 2 swings in a predetermined direction. By this swinging motion, the moving member 4 is displaced in a plane perpendicular to the longitudinal direction of the drive member 2 (in the example shown in FIG. 1, in the xz plane shown in FIG. 1).

Then, in the manufacturing process for manufacturing the optical element driving device DA having such a configuration, for example, in order to attach and fix the piezoelectric element 1A and the driving member 2 to the fixing member 3 with a thermosetting adhesive, the heating process is performed. The piezoelectric element 1A in the driving device 10 of the optical element driving device DA includes the first to third insulating protective layers 12 to 14 even when the electrical resistance value of the conductive portion 11e is reduced by the heating process. The electrical insulation between the piezoelectric element 1A and the fixing member 3 is maintained, and a short circuit between them is prevented (blocked). Therefore, the piezoelectric element 1A can perform an intended operation according to the specifications. Such first to third insulating protective layers 12 to 14 can be formed relatively easily.

Moreover, in the piezoelectric element 1A in the driving device 10 of the optical element driving device DA of the present embodiment, the first and second insulating

protective layers

12 and 13 have different shapes in plan view. For this reason, the piezoelectric element 1A having such a configuration can visually identify the positive and negative polarities of the pair of external electrode portions 11d-1 and 11d-2. In this embodiment, since the mark 13b is formed on the second insulating protective layer 13, the shapes of the first and second insulating

protective layers

12 and 13 can be made relatively simple. Can be different.

In the above-described embodiment, the first and second insulating

protective layers

12 and 13 have different shapes in plan view by forming the mark 13b on the second insulating protective layer 13, For example, the shape of the first opening 12a formed in the first insulating protective layer 12 and the shape of the second opening 13a formed in the second insulating protective layer 13 are not limited thereto. By making these different from each other in plan view, the first and second insulating

protective layers

12 and 13 may have different shapes from each other in plan view.

FIG. 5 is a diagram showing another configuration of the electromechanical transducer in the optical element driving apparatus shown in FIG. The center of FIG. 5 shows the entire electromechanical transducer 1B, the right side shows the right side of the side, the left side shows the left side of the side, and the lower side shows The front of the side is shown. Note that the rear surface of the side surface is the same as the front surface, and the illustration thereof is omitted.

This electromechanical conversion element 1B is realized by, for example, a piezoelectric element 1B, similarly to the electromechanical conversion element 1A described above. As shown in FIG. 5, the piezoelectric element 1B includes a multilayer body 11, a pair of external electrode portions 11d (11d-1, 11d-2), a conductive portion 11e (11e-1, 11e-2), The first to third insulating protective layers 16 to 18 are provided. The laminate 11, the pair of external electrode portions 11d, and the conductive portion 11e in the piezoelectric element 1B are the same as the laminate 11, the pair of external electrode portions 11d, and the conductive portion 11e in the piezoelectric element 1A, and the description thereof is omitted. To do.

The first to third insulating protective layers 16 to 18 are an example of a short-circuit prevention unit for preventing a short circuit with the member when the piezoelectric element 1B is connected to a predetermined member, for example, the fixing member 3. The first and second insulating

protective layers

16 and 17 are insulating thin films (layers) formed on the pair of external electrode portions 11d-1 and 11d-2, respectively. The third insulating protective layer 18 Is an insulating thin film (layer) formed over substantially the entire surface of the conductive portion 11e. The first insulating protective layer 16 has a rectangular first opening 16a that reaches the external electrode portion 11d-1, and covers the external electrode 11d-1 except for the region of the first opening 16a. Yes. A rectangular second opening 17a reaching the external electrode portion 11d-2 is formed in the second insulating protective layer 17, and the external electrode 11d-2 is covered except for the region of the second opening 17a. Yes.

And in this modification, the 1st opening part 16a is a long rectangle in the lamination direction of the laminated body 11, and the 2nd opening part 17a is a long rectangle in the direction orthogonal to the lamination direction of the laminated body 11. FIG. Thus, in this modification, the first and second insulating

protective layers

16 and 17 are different from each other in plan view by making the shapes of the first and

second openings

16a and 17a different from each other in plan view. It is made into a shape.

In the piezoelectric element 1A; 1B in the driving device 10 of the optical element driving device DA according to the present embodiment (including the above-described modification), the pair of external electrode portions 11d-1 and 11d-2 includes the first and first pairs. Since the two

openings

12a, 13a; 16a, 17a are exposed to the outside, for example, when a wiring such as a lead wire is soldered to the pair of external electrode portions 11d-1, 11d-2, there is a range to be soldered. Since the region to be soldered is limited by the first and

second openings

12a, 13a; 16a, 17a, the size of the solder is limited. For this reason, even if a conductive member, for example, a metal member is used as the support member SA, a short circuit between the solder and the support member SA can be prevented (see FIG. 6).

Next, another embodiment will be described.

(Second Embodiment)
Next, an embodiment of a uniaxial optical element driving device will be described. FIG. 6 is a diagram illustrating a configuration of an optical element driving device according to the second embodiment. The optical element driving device DB in the second embodiment includes a driving device 100 configured similarly to the above-described driving device 10 and a support member SB that supports the driving device 100.

More specifically, the driving device 100 includes a piezoelectric element 101 as an example of an electromechanical conversion element 101 that converts electrical energy into mechanical energy, and a columnar (axial) shape that is fixed to one end of the piezoelectric element 101. A driving member 102 that is a member to which mechanical energy converted from electric energy by the piezoelectric element 101 is transmitted; and a fixing member 103 that supports these by holding the piezoelectric element 101 and the driving member 102; And a moving member 104 which is a member engaged with the driving member 102 with a predetermined frictional force so as to be relatively movable. The piezoelectric element 101 is configured in the same manner as the above-described

piezoelectric elements

1A and 1B. In the first and second openings provided in the first and second insulating protective layers, a wiring such as a lead wire is provided. Is attached to the pair of external electrode portions. As described above, the solder 105 has a range to be soldered restricted by the first and second openings, and a region to be soldered is limited. Therefore, a conductive member such as a metal is used for the support member SB. Even if a member is used, a short circuit between the solder and the support member SB can be prevented.

The fixing member 103 of the driving device 100 is fixed to the support member SB, and a predetermined optical element (not shown) is disposed on the moving member 104 of the driving device 100.

In the optical element driving device DB having such a configuration, the moving member 104 moves along the longitudinal direction of the driving member 102 by the operation of the driving device 100. For this reason, the optical element provided on the moving member 104 can move along the longitudinal direction of the driving member 102 by the operation of the driving device 100.

Further, the optical element driving device DB having such a configuration can be used for so-called camera shake correction for correcting camera shake in one direction, for example. In addition, by using two driving devices and using two axes, the optical element driving device DB having such a configuration can be used for camera shake correction for correcting camera shake in two directions orthogonal to each other. Furthermore, the present invention can be applied to an xy stage that can move in two directions.

Next, another embodiment will be described.

(Third embodiment)
In the above-described embodiment, the

piezoelectric elements

1A, 1B, 101 as the

electromechanical conversion elements

1A, 1B, 101 and the predetermined members are provided by providing the first to third insulating protective layers 12-14; 16-18. In the example, a short circuit with the fixing

members

3 and 103 is prevented. However, as another example of the insulation preventing portion, an insulating spacer having an insulating property may be included in the conductive portion 11e. For this insulating spacer, for example, ceramic beads having insulating properties that are not easily elastically deformed are used.

When the

piezoelectric members

1A, 1B, 101 and the

drive members

2, 102 are fixed to the fixing

members

3, 103, they may be pressed to fix them firmly. When pressed, in the conductive portion 11e of the conductive resin, for example, metal or carbon in the conductive resin may be deformed by the pressing and come into contact with each other. As a result, the electrical resistance value of the conductive portion 11e is reduced, causing a short circuit. Therefore, by including an insulating spacer that is not easily elastically deformed in the conductive portion 11e as in the present embodiment, it is possible to suppress a decrease in the electrical resistance value of the conductive portion 11e and prevent a short circuit.

This specification discloses various modes of technology as described above, and the main technologies are summarized below.

An electromechanical transducer according to one aspect is an electromechanical transducer that converts electrical energy into mechanical energy, and is formed on a predetermined surface, and a pair of electrode portions for supplying the electrical energy; A conductive portion formed on a surface different from the predetermined surface on which the electrode portion is formed, and a conductive portion having conductivity, and a short-circuit preventing portion for preventing a short circuit with the member when connected to the predetermined member, Is provided.

In another aspect, the electromechanical transducer is an electromechanical transducer that converts electrical energy into mechanical energy, and is formed on a predetermined surface, and a pair of electrode portions for supplying the electrical energy; A short-circuit preventing portion for preventing a short circuit with the member when connected to a predetermined member, the short-circuit preventing portion having an insulating property and a pair formed on the pair of electrode portions, respectively. The first and second insulating layers, and a third insulating layer having an insulating property and formed on a surface different from the predetermined surface on which the pair of electrode portions are formed, and the pair of the first insulating layers. The second insulating layer includes a first opening and a second opening, which are openings exposed to supply power from outside.

Since the electromechanical conversion element having such a configuration is provided with the short-circuit prevention unit, it is possible to prevent a short circuit with the predetermined member even when heated. The short-circuit prevention unit includes the first and second insulating layers on the pair of electrode portions, and the third insulating layer on a surface different from the predetermined surface on which the pair of electrode portions are formed. It can be provided relatively easily. And since it has the 1st and 2nd opening which is an opening exposed in order to supply electric power from the outside, when soldering wiring, such as a lead wire, to a pair of electrode parts in order to supply electric power from the outside, Since the range to be attached is restricted by the first and second openings and the area to be soldered is limited, the size of the solder is limited. Therefore, the electromechanical transducer having such a configuration can prevent a short circuit between the solder and the support member even when a conductive member such as a metal member is used as the support member.

In another aspect, in the above-described electromechanical transducer, the first and second insulating layers have different shapes in plan view.

Since the electromechanical transducer having such a configuration has different shapes in plan view of the first and second insulating layers, the polarities of the pair of electrode portions can be identified.

In another aspect, in the above-described electromechanical transducer, the first and second insulating layers have different shapes in plan view by including marks formed on at least one of them.

The electromechanical transducer having such a configuration includes the marks formed on at least one of the first and second insulating layers, so that each shape of the first and second insulating layers can be relatively easily achieved. Can be different from each other.

According to another aspect, in the electromechanical transducer described above, the first and second insulating layers are formed in a plan view by making shapes of the first and second openings different from each other in a plan view. Different shapes.

In the electromechanical transducer having such a configuration, the shapes of the first and second insulating layers can be made relatively different from each other by making the shapes of the first and second openings different from each other. it can.

In another aspect, in the above-described electromechanical transducer, the conductivity formed between the third insulating layer and a surface different from the predetermined surface on which the pair of electrode portions are formed is provided. The electroconductive part which has further is provided.

In the electromechanical transducer having such a configuration, even when the conductive portion is provided on a surface different from the predetermined surface on which the pair of electrode portions are formed, A short circuit between the member and the conductive portion can be prevented.

Further, the driving device according to another aspect includes any one of the above-described electromechanical conversion elements. Further, a driving apparatus according to another aspect includes any one of the above-described electromechanical conversion elements, a driving member fixed to the electromechanical conversion element, to which the mechanical energy is transmitted, and a predetermined amount applied to the driving member. A moving member engaged by a frictional force and a fixing member for fixing as the predetermined member are provided.

Since the drive device having such a configuration includes any of the electromechanical conversion elements described above, even when assembled to the fixed member, a short circuit with the fixed member can be prevented.

This application is based on Japanese Patent Application No. 2010-259666 filed on November 22, 2010, the contents of which are included in the present application.

In order to express the present invention, the present invention has been properly and fully described through the embodiments with reference to the drawings. However, those skilled in the art can easily change and / or improve the above-described embodiments. It should be recognized that this is possible. Therefore, unless the modifications or improvements implemented by those skilled in the art are at a level that departs from the scope of the claims recited in the claims, the modifications or improvements are not covered by the claims. It is interpreted that it is included in

Claims

An electromechanical transducer that converts electrical energy into mechanical energy,
A pair of electrode portions formed on a predetermined surface for supplying the electric energy;
A short-circuit prevention unit for preventing a short circuit with the member when connected to a predetermined member,
The short-circuit prevention portion has an insulating property, and the predetermined first and second insulating layers formed on the pair of electrode portions, respectively, and the predetermined one having the insulating property and forming the pair of electrode portions. A third insulating layer formed on a surface different from the surface of
The pair of first and second insulating layers have first and second openings, which are openings exposed to supply power from outside, respectively.
The electromechanical transducer according to claim 1, wherein the first and second insulating layers have different shapes in plan view.
The electromechanical transducer according to claim 2, wherein the first and second insulating layers have different shapes in a plan view by including a mark formed on at least one of the first and second insulating layers.
The said 1st and 2nd insulating layer becomes a mutually different shape in planar view by making the shape in planar view of the said 1st and 2nd opening part mutually differ. Electromechanical transducer.
The electroconductive part which has the electroconductivity formed between the surface different from the said predetermined surface in which the said pair of electrode part was formed, and the said 3rd insulating layer is further provided. The electromechanical transducer according to any one of 4.
A drive device comprising the electromechanical transducer according to any one of claims 1 to 5.
The electromechanical transducer according to any one of claims 1 to 5,
A drive member fixed to the electromechanical transducer and to which the mechanical energy is transmitted;
A moving member engaged with the driving member with a predetermined frictional force;
A driving device comprising: a fixing member for fixing as the predetermined member.