JPH1126830A - Stacked actuator - Google Patents

Abstract

(57) [Problem] To provide a laminated actuator in which both the stroke and the generated force are greater than those of a single planar deformation element such as a piezoelectric bimorph or a piezoelectric unimorph. SOLUTION: The laminated actuator of the present invention is configured by joining four laminated units U1 to U4 in series. In each laminated unit, the piezoelectric unimorphs 1A to 1H
Are superposed two by two and are coaxially arranged. The central part is connected to the central connecting member 21 and the outer peripheral part is connected to the outer peripheral connecting member 31. Thus, a double generated force is obtained. Each of the stacked units U1 to U4 is arranged to face each other or face backward, and is alternately connected by the unit center connecting member 22 and the unit outer circumferential connecting member 32, and a stroke four times that of the single stacked unit is exerted. . In this way, twice the generating force and four times the stroke of the piezoelectric unimorph alone are exhibited.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a piezoelectric unimorph,
A plurality of planar deformation elements such as a piezoelectric bimorph or a bimetal are laminated, and belong to the technical field of a laminated actuator that performs expansion and contraction operations.

[0002]

2. Description of the Related Art In applications such as a focus adjusting mechanism of a microscope and a moving mechanism of a micro machine, there is a demand for an actuator which is small in size and has both large displacement (stroke) and large generated force. In response to this problem, the inventors have invented several types of laminated piezoelectric actuators, and have filed applications under the same applicant. For example, Japanese Patent Application Laid-Open No. 9-3775
Japanese Unexamined Patent Publication No. 7-1932 (Prior Art 1) discloses a laminated piezoelectric actuator having a large generating force.
No. 90 (Prior Art 2) discloses a laminated piezoelectric actuator having a large stroke.

However, both of the prior arts have the following advantages and disadvantages, and cannot simultaneously satisfy a large generating force and a long stroke. That is, in the multilayer piezoelectric actuator of the prior art 1,
A plurality of piezoelectric bimorphs are stacked, the central portions of all the piezoelectric bimorphs are connected by a central connecting member, and the outer peripheral portions of all the piezoelectric bimorphs are connected by an outer peripheral connecting member. Therefore, according to the laminated piezoelectric actuator, the generated force is increased by the number of laminated layers, but the stroke is not increased from a single piezoelectric bimorph.

On the other hand, in the multi-layer piezoelectric actuator of the prior art 2, piezoelectric unimorphs are alternately arranged to face each other.
The center and outer periphery of each piezoelectric unimorph were connected alternately. Therefore, according to this laminated piezoelectric actuator, the stroke is increased by the number of laminated piezoelectric unimorphs, but the generated force is not increased from a single piezoelectric unimorph.

[0005]

SUMMARY OF THE INVENTION Therefore, the present invention is to solve the problem of providing a laminated actuator in which both the stroke and the generated force are larger than those of a single planar deformation element such as a piezoelectric bimorph or a piezoelectric unimorph. Make it an issue.

[0006]

Means for Solving the Problems and Their Functions and Effects In order to solve the above problems, the inventors have invented the following means. (First Means) A first means of the present invention is a laminated actuator according to the first aspect. In this means, the stacking unit is a planar deformation element in which a plurality of sheets are stacked and arranged coaxially, and generates a displacement in the axial direction between the central portion and the outer peripheral portion,
A central connecting member connects the central portions of the planar deformation elements to each other in the axial direction, and an outer peripheral connecting member connects the outer peripheral portions of the planar deformation elements to each other in the axial direction. In each stacking unit, the center connecting member and the outer circumferential connecting member can move relative to each other coaxially by the deformation of the plane deforming element, and a generating force corresponding to the number of stacked plane deforming elements can be obtained. That is, in each stacking unit, the plane deforming elements are connected in parallel with respect to the stroke, and the generated force is obtained by the number of stacked plane deforming elements, but the stroke does not increase from the stroke of the plane deforming element alone.

Next, the stacked units adjacent to each other are connected by a unit central connecting member connecting the inner peripheral connecting members when the relative moving directions are opposite to each other, and when the relative moving directions are opposite to each other. Are connected by a unit outer peripheral connecting member that connects the respective outer peripheral connecting members.
Or, conversely, when the relative movement directions are opposed to each other, they are connected to each other by the unit outer peripheral connection member, and when the relative movement directions are opposite to each other, they are connected to each other by the unit central connection member. That is, each of the stacked units is connected in series with respect to the stroke, and the stroke is increased by the number of connections of the connected stacked units, but the generated force does not increase from the single stacked unit.

Therefore, when the M planar deformation elements are laminated to form each laminated unit, and the N laminated units are connected and laminated to form a laminated actuator, the generated force is the planar deformation. M times the element alone and N times the stroke of the plane deforming element alone are exhibited. Conversely, if it becomes clear how many times (M times) the generating force is required for the plane deforming element alone and how many times (N times) the stroke is required for the plane deforming element alone, M sheets are required. What is necessary is just to form a laminated actuator by laminating the planar deformation elements to form each laminated unit and connecting the N laminated units.

Therefore, according to this means, there is an effect that it is possible to provide a laminated actuator in which both the stroke and the generated force are larger than those of a single planar deformation element such as a piezoelectric bimorph or a piezoelectric unimorph.
Also, if the necessary force and stroke are clear,
It is also clear how many planar deformation elements are to be laminated to form each laminated unit, and how many laminated units are to be connected to form a laminated actuator, which also has the effect of facilitating design.

The center connecting member and the unit center connecting member may be formed continuously, and similarly, the outer connecting member and the unit outer connecting member may be formed continuously. Further, the central connecting member and the unit central connecting member may be hollow cylindrical members. This makes it possible to use the hollow internal spaces of the central connecting member and the unit central connecting member for the optical path of the microscope. Similarly, the outer peripheral connecting member and the unit outer peripheral connecting member may be a bipe-shaped member surrounding the entire periphery of the planar deformation element. Furthermore, if the wall surface of the pipe-shaped member is formed in a mesh shape, the ventilation becomes better, so that the cooling becomes better and the trouble due to overheating is avoided.

(Second Means) The second means of the present invention is a laminated actuator according to the second aspect. According to this means, when a piezoelectric unimorph or a piezoelectric bimorph is employed as the plane deformation element, there is an effect that a quick response characteristic can be obtained from the laminated actuator with a small power consumption.

Conversely, when a bimetal is employed as the planar deformation element, it can be manufactured at a lower cost because it does not have a complicated structure unlike a piezoelectric bimorph or a piezoelectric unimorph. In addition, when a bimetal is used as the plane deformation element, there is no need to apply a driving voltage to the plane deformation element, so that it is possible to eliminate the need for a cable and to simplify the configuration of the stacked actuator. .

(Third Means) A third means of the present invention is a laminated actuator according to the third aspect. In this means, since all the laminated units are formed to have the same standard including the type and the number of the planar deformation elements, the generated force and the stroke of each laminated unit are the same. as a result,
Since the deformation and the load become uniform in all the plane deformation elements of all the stacked units and are not biased to any one of the plane deformation elements, the stacking effect can be obtained without waste and the efficiency becomes the best.

Therefore, according to the present invention, the load on each of the planar deformation elements is the same, and there is no partial bias, so that there is an effect that the lamination efficiency of the planar deformation element and the lamination unit is optimized. In addition, the indication that the design by the first means becomes easy is described on the premise of the conditions of the present means.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the multilayer actuator according to the present invention will be clearly and fully described in the following embodiments so that those skilled in the art can understand the embodiments. Embodiment 1 (Structure of Embodiment 1) As shown in FIGS. 1A and 1B, a multilayer actuator according to Embodiment 1 of the present invention has eight disk-shaped piezoelectric unimorphs 1A to 1H. Are laminated. The eight piezoelectric unimorphs 1A to 1H are connected to the outer connecting member 31 and the center connecting member 21 two by two, and are divided into four laminated units U1 to U4.
The stacked units U1 to U4 differ in the direction in which they are connected, but are all stacked units of the same standard and have compatibility. Therefore, a description will be given of the laminated unit U1 as an example.

As shown in FIG. 2A, the laminated unit U1 is composed of two piezoelectric unimorphs 1A, 1 facing in the same direction.
B, a central connecting member 21 connecting the central portions of the piezoelectric unimorphs 1A, 1B to each other in the axial direction, and four locations of the outer peripheral portions of the piezoelectric unimorphs 1A, 1B to each other in the axial direction. It comprises four outer peripheral connecting members 31. Each of the piezoelectric unimorphs 1A and 1B includes one elastic plate 11 made of stainless steel, a ring-shaped piezoelectric plate 12 joined to the lower surface of the elastic plate 11, and a surface electrode formed on the surface of the piezoelectric plate 12. 13. The central connecting member 21 at the center and the four outer connecting members 31 arranged in four directions are respectively joined to the elastic plates 11 of the piezoelectric unimorphs 1A and 1B by laser welding.
Therefore, the elastic plate 11 of each of the piezoelectric unimorphs 1A and 1B, the inner connecting member, and the outer connecting member 31 are electrically connected to each other.

The unit center connecting member 22 is a round bar having the same standard as the center connecting member 21 and is coaxially joined to the elastic plate 11 of the piezoelectric unimorph 1B by laser welding. Therefore, the unit center connecting member 22 is electrically connected to the elastic plate 11 of the piezoelectric unimorph 1B. However, the unit center connection member 22 is not included in the stacking unit U1, but is a member for connecting the stacking unit U1 and the stacking unit U2 to each other at the center.

Each of the piezoelectric unimorphs 1A and 1B is shown in FIG.
As shown in (b), the two sheets are stacked in the same direction and arranged coaxially, and a displacement in the axial direction occurs between the central portion and the outer peripheral portion. That is, in the laminated unit U1, the central connecting member 21 and the outer peripheral connecting member 31 can move relative to each other coaxially by deformation of the piezoelectric unimorphs 1A and 1B. The length in the axial direction in the state where there is no applied voltage shown in FIG. 2A is defined as l (ell), and the length in the operating state where the applied voltage is applied shown in FIG. l + Δl), the stroke of the laminated unit U1 by the applied voltage is Δl
It is.

As shown in FIG. 1 (b), each of the laminated units U1 to U4 is coaxially laminated so as to face or face the adjacent laminated unit. That is, between the laminated units (U1 and U2, U3 and U4) adjacent to each other with their relative movement directions facing each other, they are connected to each other at the center by the unit central connecting member 22 that connects the respective inner peripheral connecting members 21. ing. Here, the unit center connecting member 22 between the laminated units U1 and U2 is
Elastic plate 11 of piezoelectric unimorph 1B and piezoelectric unimorph 1C
To the elastic plate 11 by laser welding.

On the other hand, between the adjacent stacked units (U2 and U3) whose relative movement directions are opposite to each other, the outer peripheral portions are connected to each other at the outer peripheral portion by the unit outer peripheral connecting members 32 for connecting the respective outer peripheral connecting members 31 to each other. Have been. The above has faithfully described the basic concept that each of the stacked units U1 to U4 is independently configured, and then stacked coaxially facing each other or facing each other to form a stacked actuator. However, in the case of actual manufacturing, the way of explanation differs depending on manufacturing convenience. That is, the above-mentioned two outer peripheral connecting members 31 and the unit outer peripheral connecting member 32 connecting the both 31 are formed of a continuous and integral round bar made of stainless steel.
Shall be called. Similarly, the unit inner connecting member 22 sandwiched between the two inner connecting members 21 and the elastic plate 11 via the elastic plate 11 can be formed of a continuous and integral round bar made of stainless steel. The round bar is referred to as a center support 2. In this case, a through hole is formed in the center of each of the piezoelectric unimorphs 1A to 1H.
(Which is easier to manufacture and has higher strength).

FIG. 1 (b) schematically shows a drive circuit including a constant-voltage DC power supply E and a switch S outside the multilayer actuator. One pole of the power source E is connected to the respective elastic plates 11 of all the piezoelectric unimorphs 1A to 1H via the lead wire C2 and the outer peripheral connecting member 31 and the like.
It is conducting. The other pole of the power supply E can be simultaneously connected to the respective surface electrodes 13 of all the piezoelectric unimorphs 1A to 1H via the switch S and the branched lead C1.

(Effects of Embodiment 1) Since the multilayer piezoelectric actuator of this embodiment is configured as described above, it exhibits the following effects. First, in each of the laminated units U1 to U4, the center connecting member 21 and the outer peripheral connecting member 31 can move relative to each other coaxially by deformation of the piezoelectric unimorphs 1A to 1H, and each corresponds to the number of stacked piezoelectric unimorphs, that is, two piezoelectric unimorphs. Is generated. Also,
In each of the laminated units U1 to U4, the piezoelectric unimorphs 1A to 1
H are connected in parallel with respect to the stroke, and the generated force is obtained by the number of laminated piezoelectric unimorphs (two).
The stroke does not increase from the stroke of the piezoelectric unimorph alone.

Next, the adjacent stacked units U1 to U1
When the relative movement directions are opposite to each other, U4 is connected by a unit central connecting member 22 that connects the respective inner peripheral connecting members 21. Conversely, when the relative movement directions are opposite to each other, they are connected by a unit outer circumferential connecting member 32 connecting the respective outer circumferential connecting members 31. In other words, each of the stacked units U1 to U4 is connected in series with respect to the stroke, and the stroke increases by the number of connections (ie, four times) of the connected stacked units, but the generated force increases from the single stacked unit. There is no.

Specifically, as shown in FIGS. 3A and 3B, when an applied voltage is applied, the laminated actuator expands from the original length L to L ′ (= L + ΔL = L + 4 × Δl). I do. In other words, two of the piezoelectric unimorphs 1A to 1H are laminated to form each laminated unit, and four laminated units U1 to U4 are connected and laminated to form a laminated actuator. The stroke is twice as large as that of a unimorph unit and the stroke is four times that of a piezoelectric unimorph unit.

Therefore, according to the laminated piezoelectric actuator of this embodiment, there is an effect that a stroke four times as large as that of the piezoelectric unimorph alone and a force twice as large are exerted.
Since an appropriate distance is provided between the outer peripheral support 3 and the outer peripheral connecting members 31 at both ends, the stacked actuator can be contracted by applying an applied voltage in reverse. Also in this case, the same effect of increasing the stroke and the generated force as in the case of the above-described extension can be obtained.

(Modification 1 of Embodiment 1) As Modification 1 of this embodiment, it is possible to implement a laminated actuator using a piezoelectric bimorph instead of the piezoelectric unimorphs 1A to 1H. According to the present modification, there is an effect that the generated force is increased and a contraction action similar to the extension action is obtained.

(Modification 2 of Embodiment 1) As Modification 2 of this embodiment, as shown in FIGS. 4A and 4B, two types of thermal expansion coefficients are used instead of the piezoelectric unimorphs 1A to 1H. However, it is possible to implement a laminated actuator using a bimetal formed by laminating metal plates 11 ′ and 12 ′ that are different from each other. According to this modification, although temperature control is necessary, no applied voltage is required, so that there is an effect that wiring such as a lead wire can be eliminated and the configuration can be simplified.

Embodiment 2 (Structure of Embodiment 2) As shown in FIGS. 5A and 5B, a multilayer actuator as Embodiment 2 of the present invention has eight piezoelectric unimorphs 1A to 1H. Are the same as in the first embodiment in that each of the stacked units U1 to U4 is formed in pairs. This embodiment is different from the first embodiment in that
Unit central connecting member 22 and unit outer peripheral connecting member 32
Is a point where the position is reversed.

That is, the lamination units (U1 and U2, U3 and U3
Between 4), the outer peripheral connecting members 32 are connected to each other at the outer peripheral portions by unit outer peripheral connecting members 32 that connect the outer peripheral connecting members 31. On the other hand, between the laminated units (U2 and U3) adjacent to each other with their relative movement directions facing each other, they are connected to each other at the center by unit inner peripheral connecting members 22 that connect the respective inner peripheral connecting members 21 to each other. ing.

Although the above has faithfully described the basic concept of forming each of the laminated units U1 to U4 independently and then laminating coaxially to face or face each other to form a laminated actuator, As in the first embodiment, the way of explanation is different due to the above circumstances. That is, the above-mentioned two outer peripheral connecting members 31 and the unit outer peripheral connecting member 32 connecting the both 31 are formed of a continuous and integral round bar (outer peripheral column 3) made of stainless steel. Similarly, the unit inner connecting member 22 sandwiched between the two inner connecting members 21 and the elastic plate 11 via the elastic plate 11 is a continuous and integral round bar (central support 2) made of stainless steel. Can be formed. In this case, each of the piezoelectric unimorphs 1A to 1H is formed with a through hole at the center thereof, and the center support 2 and the center connecting member 21 are formed.
May be fitted in the through holes and laser-welded to each elastic plate 11.

It is to be noted that a driving circuit including a constant-voltage DC power supply E and a switch S is provided as in the first embodiment.
That is, the driving circuit includes the elastic plates 11 of all the piezoelectric unimorphs 1A to 1H and the respective surface electrodes 1 of all the piezoelectric unimorphs 1A to 1H via the outer circumferential support 3.
3 so that an applied voltage can be applied.

(Effects of the Second Embodiment) In the multilayer piezoelectric actuator of the present embodiment, similarly to the first embodiment, there is an effect that four times the stroke and twice the generating force of the piezoelectric unimorph alone are exhibited. is there. However, since the way of connection between the stacked units by the unit central connecting member 22 and the unit outer circumferential connecting member 32 between the stacked units U1 to U4 is reversed, as shown in FIGS. Instead of the action, a contraction action is exerted. At this time, the stroke ΔL ′ (= L ″ −L) is a negative four times (−4 × Δl) of the stroke Δl of each of the laminated units U1 to U4.
be equivalent to.

(Modification 1 of Embodiment 2) As Modification 1 of this embodiment, as shown in FIGS. 7A and 7B, piezoelectric bimorphs 1A 'to 1A' instead of piezoelectric unimorphs 1A to 1H are used.
Implementation of a stacked actuator using 1H 'is possible. According to this modification, in addition to the increase in generated force,
As shown in FIGS. 8A and 8B, there is an effect that the stretching action and the contracting action can be similarly obtained by both the stroke and the generated force.

(Modification 2 of Embodiment 2) As Modification 2 of the present embodiment, similarly to Modification 2 of Embodiment 1, a multilayer actuator using a bimetal instead of the piezoelectric unimorphs 1A to 1H is described. Is possible. According to this modification, although temperature control is necessary, no applied voltage is required, so that there is an effect that wiring such as a lead wire can be eliminated and the configuration can be simplified.

[Embodiment 3] As shown in FIGS. 9A and 9B, a multilayer actuator according to Embodiment 3 of the present invention has eight disk-shaped piezoelectric unimorphs 1A to 1H stacked. It is configured. Eight piezoelectric unimorphs 1A to 1H
Are connected by the outer peripheral connecting member 31 and the central connecting member 21 four by four, and are divided into two laminated units UA and UB. The stacked units UA and UB are connected to face each other, but both are stacked units of the same standard and are interchangeable. Therefore, a description will be given next by taking the laminated unit UA as an example.

The laminated unit UA is composed of four piezoelectric unimorphs 1A to 1D facing the same direction and each piezoelectric unimorph 1A.
A central connecting member 21 that connects the central portions of A to 1D to each other in the axial direction, and four outer peripheral connecting members that connect the four peripheral portions of the piezoelectric unimorphs 1A to 1D to each other in the axial direction. 31. The respective configurations of the piezoelectric unimorphs 1A to 1D are the same as those of the piezoelectric unimorphs 1A to 1H of the first embodiment.
The configuration is the same as And the central connecting member 2 at the center
The four outer peripheral connecting members 31 disposed in one and four directions are:
Each piezoelectric unimorph 1A ~ 1D by laser welding
To the elastic plate 11.

The unit central connecting member 22 is a round bar having the same standard as the central connecting member 21. The elastic plate 11 of the piezoelectric unimorph 1D and the elastic plate 1 of the piezoelectric unimorph 1E are used.
1 and are coaxially joined to the center connecting member 21 by laser welding. Each of the piezoelectric unimorphs 1A to 1D is stacked coaxially in the same direction, and is displaced in the axial direction between the central portion and the outer peripheral portion. That is, in the laminated unit UA, the center connecting member 21 and the outer peripheral connecting member 31 can move relative to each other coaxially by deformation of each of the piezoelectric unimorphs 1A to 1D.

Now, as shown in FIG. 9B again, the respective laminating units UA and UB are adjacent to each other and are coaxially laminated. In other words, between the stacked units UA and UB adjacent to each other with their relative movement directions facing each other, the stacked units UA and UB are connected to each other at the center by the unit center connecting member 22 connecting the respective inner peripheral connecting members 21. Here, the unit central connecting member 22 between the laminated units UA and UB is connected to the elastic plate 11 of the piezoelectric unimorph 1D.
And the elastic plate 11 of the piezoelectric unimorph 1E, respectively, by laser welding.

The above has faithfully described the basic concept that each of the stacked units UA and UB is independently formed, and then the stacked units are coaxially stacked so as to face each other to form a stacked actuator. However, in the case of actual production, Example 1
In the same way as described above, the way of explanation differs depending on the manufacturing convenience.
That is, the above-mentioned six inner peripheral connecting members 21 and the elastic plate 11
Unit central connecting member 2 sandwiched between both 21 through
2 can be formed of a continuous and integral round bar (central support 2 ′) made of stainless steel. In this case, each of the piezoelectric unimorphs 1A to 1H has a through-hole formed in the center thereof, and the center support 2 is fitted to the through-hole and laser-welded to each elastic plate 11 (this is better). It is easy to manufacture and the strength is improved). In addition, the outer peripheral connecting member 31
Can also be formed of a stainless steel round bar member, and will be referred to as an outer column 3 ′ for convenience (however, the embodiment does not include the unit outer connecting member 32). 1).

As in the first embodiment, a driving circuit including a constant-voltage DC power supply E and a switch S is provided outside the laminated actuator, and all the piezoelectric unimorphs 1A to 1H
Can be electrically connected to the respective elastic plates 11 and the respective surface electrodes 13. (Effects of Embodiment 3) Since the laminated piezoelectric actuator of this embodiment is configured as described above, Embodiment 1
The following functions and effects are exhibited by the same principle as described above.

First, in each of the laminated units UA and UB, the center connecting member 21 and the outer circumferential connecting member 31 can move relative to each other coaxially by deformation of the piezoelectric unimorphs 1A to 1D and 1E to 1H. The generated force for the number of stacked sheets, that is, four sheets, is obtained. In each of the laminated units UA and UB, the piezoelectric unimorphs 1A to 1D and 1E to 1E
H are connected in parallel with respect to the stroke, and the generated force is obtained by the number of stacked piezoelectric unimorphs (four).
The stroke does not increase from the stroke of the piezoelectric unimorph alone.

Next, the adjacent stacked units UA,
Since the UBs are opposed to each other in the relative movement direction, the unit central connecting member 2 for connecting the respective inner peripheral connecting members 21 is connected.
They are connected by two. That is, each laminated unit UA,
The UBs are connected in series with respect to the stroke, and the stroke increases by the number of connections (ie, double) of the connected stacked units, but the generated force does not increase from the single stacked unit alone.

More specifically, four of the piezoelectric unimorphs 1A to 1H are laminated, and each of the laminated units UA, U
B is formed, and the two stacked units UA and UB are connected to form a stacked actuator, so that the generated force is four times that of the piezoelectric unimorph alone and the stroke is twice that of the piezoelectric unimorph alone. Therefore, according to the laminated piezoelectric actuator of the present embodiment, there is an effect that a double stroke and a quadruple generation force of the piezoelectric unimorph alone are exhibited.

As in the case of the first embodiment, since an appropriate distance is provided between the outer peripheral column 3 and the outer peripheral connecting members 31 at both ends, the laminated actuator is contracted by applying an applied voltage in reverse. It can also be done. (Various Modifications of Embodiment 3) The piezoelectric unimorphs 1A to 1H are also replaced with piezoelectric bimorphs and bimetals in the multilayer actuator of the present embodiment, similarly to Modifications 1 and 2 of Embodiment 1. Various modifications can be made. Also in these modifications, the operation and effect equivalent to the operation and effect of the modification 1 and the modification 2 of the first embodiment can be obtained.

[Supplementary description of the embodiment] If the M planar deformation elements are stacked to form each stacked unit and the N stacked units are connected and stacked to form a stacked actuator, The generated force is M times that of the plane deforming element alone, and the stroke is N times that of the plane deforming element alone. Therefore, if 12 piezoelectric unimorphs are to be laminated to constitute a laminated actuator of the present invention, M
The combination of × N is 2 × 6, 3 × 4, 4 × 3, 6 × 2
There are four possible ways.

To put it the other way around, how many times (M
Times as much force as the plane deformation element alone (N
If it becomes clear whether a stroke of 2 times) is necessary, M
The planar deformation elements are laminated to form each laminated unit, and N
What is necessary is just to constitute a laminated actuator by connecting the laminated units. Therefore, if, for example, three times the generating force and four times the stroke of the piezoelectric unimorph alone are required, twelve piezoelectric unimorphs are stacked according to the above-described method with M × N = 3 × 4. Thus, a multilayer actuator may be configured.

Therefore, according to the present invention, when the necessary force and stroke are clarified, a number of piezoelectric unimorphs and the like are laminated to form each laminated unit, and a number of laminated units are connected to form a laminated actuator. It is also clear whether or not to configure, and there is also an effect that the design is easy.

[Brief description of the drawings]

FIG. 1 is an assembly diagram showing a configuration of a multilayer actuator as a first embodiment (a) Plan view (b) Side end view

FIGS. 2A and 2B are assembly diagrams illustrating the operation of the stacking unit according to the first embodiment. FIG.

FIG. 3 is a set diagram showing the operation of the multilayer actuator as the first embodiment. (A) Side end view when not operating (b) Side end view when operating

FIG. 4 is a set diagram showing a configuration of a stacked actuator according to Modification 2 of Example 1 (a) Plan view (b) Side end view

FIG. 5 is a set diagram showing a configuration of a multilayer actuator as a second embodiment (a) Plan view (b) Side end view

FIG. 6 is a set diagram showing the operation of the multilayer actuator as the second embodiment. (A) Side end view when not operating (b) Side end view when operating

FIG. 7 is a set diagram showing the configuration of a stacked actuator according to Modification 1 of Embodiment 2 (a) Plan view (b) Side end view

FIG. 8 is a set diagram showing the operation of the stacked actuator according to the first modification of the second embodiment; (a) a side end view showing a contraction operation; and (b) a side end view showing an extension operation.

FIG. 9 is a set diagram showing a configuration of a multilayer actuator as a third embodiment (a) Plan view (b) Side end view

[Explanation of symbols]

1, 1A-1H: Piezoelectric unimorph 1 ', 1A'-1
H ': piezoelectric bimorph 11: elastic plate 12: piezoelectric plate 13: surface electrode 1 ", 1A" to 1H ": bimetal 11", 12 ": metal plate (different in coefficient of thermal expansion) 2, 2': center support 21 : Central connecting member 22: Unit central connecting member 3, 3 ': Outer peripheral support member 31: Outer peripheral connecting member 32: Unit outer peripheral connecting member U1 to U4: Stacking unit (two piezoelectric unimorphs) U1' to U4 ': Stacking unit (piezoelectric U1 "to U4": Laminated unit (two bimetals) UA, UB: Laminated unit (four piezoelectric unimorphs) C1, C2: Lead wires E, E1, E2: DC power supply
S: Switch

Claims (3)

[Claims] 1. A planar deforming element in which a plurality of sheets are stacked and coaxially arranged to cause displacement in an axial direction between a central portion and an outer peripheral portion, and a central portion of each of the planar deforming elements is arranged in an axial direction. A central connecting member connected to each other; and an outer connecting member connecting the outer peripheral portions of the respective planar deforming elements to each other in the axial direction. The central connecting member and the outer peripheral connecting member are deformed by the deforming of the planar deforming element. A plurality of stacked units whose members are relatively movable coaxially, and a unit central connecting member for connecting the respective inner peripheral connecting members between the stacked units adjacent to each other with their relative movement directions facing each other; The unit central connecting member and the unit outer peripheral connecting member between one of the unit outer peripheral connecting members connecting the respective outer peripheral connecting members to each other and the adjacent stacked units whose relative movement directions are opposite to each other; A laminated actuator having at least one of the other of the binding members. 2. The multilayer actuator according to claim 1, wherein the planar deformation element is one of a piezoelectric unimorph, a piezoelectric bimorph, and a bimetal. 3. The multilayer actuator according to claim 1, wherein each of the multilayer units is formed to have the same standard including the type and the number of the planar deformation elements.