JP3354803B2 - Piezo actuator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric actuator for mechanically enlarging a minute displacement of a piezoelectric element by using the piezoelectric element as a drive source, and is used, for example, for driving a shutter blade of a camera.

[0002]

2. Description of the Related Art Conventionally, two (one pair) lever arms are connected to both side surfaces of a substrate and a piezoelectric element arranged on the side thereof via hinge portions (connection portions). 2. Description of the Related Art A piezoelectric actuator is known in which a beam as a displacement enlarging means is connected so as to be sandwiched between tip ends of a lever arm of the book. In such a piezoelectric actuator, the lever arm has a width dimension of a hinge portion. Japanese Patent Application Laid-Open No. 1-161790 proposes a laminated structure in which a predetermined number of thin metal plates each having a smaller thickness are stacked.

[0003]

In a conventional piezoelectric actuator, the amount of displacement of a piezoelectric element is temporarily increased to some extent by a lever arm, and then the beam is bent by the displacement to displace the central portion thereof. It is. Therefore, in order to finally obtain a large displacement, the magnification by the lever arm must be increased, which results in an increase in the size of the beam. There is a problem that fatigue fracture is likely to occur.

When the lever arm has a laminated structure in which a predetermined number of thin metal plates each having a thickness smaller than the width of the hinge portion are stacked, the structure of the lever arm is complicated although the metal fatigue is improved. There is a problem that it becomes.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a method for controlling the displacement of a piezoelectric element to a beam supported at both ends between a first support and a second support. The beam can be deformed into an arc shape by transmitting it directly or in an enlarged manner, and a U-shaped punched hole is provided at the deformed portion of the beam with a lever whose free end is the free end.
Are formed integrally with the beam .

In addition, the displacement of the piezoelectric element is directly or enlargedly transmitted to the first beam and the second beam supported at both ends between the first support and the second support. The first beam and the second beam are arcuately deformed in directions opposite to each other, and the first beam and the second beam are rotatably provided at the deformed portions of the first beam and the second beam via a connecting portion. The other end of the second lever is slidably connected to one end of the second lever, and the other end of the second lever is supported by the second support portion in the same manner as the second beam.
The other end of the lever is a free end.

[0007] With these configurations, it is possible to provide a small-sized piezoelectric actuator having a high displacement magnification with a simple configuration.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a piezoelectric actuator according to the present invention, a first support portion and a second support portion are provided so as to be able to reduce an interval between them by a piezoelectric element which expands and contracts according to a voltage applied to an electrode. A beam that can be elastically deformed in an arc in a certain direction is supported at both ends between the two support portions, and the beam extends from the deformed portion of the beam in the moving direction of the two support portions. A lever whose extension end is a free end is provided, and the beam is composed of a plate-like member,
The lever is provided with a U-shaped punched hole in the beam.
Is formed integrally with the beam .

[0009] Preferably, bi chromatography beam, in order to elastically deform in an arc in a predetermined direction, may be supported between the two support portions in a state of being deformed to project into a certain direction.

Further, in the piezoelectric actuator according to the present invention, the first support portion and the second support portion are provided so as to be able to reduce the distance between them by a piezoelectric element which expands and contracts according to a voltage applied to the electrode. A first beam elastically deformable in an arc shape in a first direction and a second beam elastically deformable in an arc shape in a second direction opposite to the first direction between both support portions; The first beam is provided with a first lever rotatably via a connecting portion at a deformed portion of the first beam, and the second beam is provided with a second beam A second lever is rotatably provided at the deformed portion via a connecting portion, and one end of the first lever and one end of the second lever are slidably connected to each other. The other end of the lever is a free end, and the other end of the second lever is a second support like the second beam. Sometimes supported by the.

Preferably, the first beam and the second beam
Is composed of a plate-like member, and the first lever and the second lever may be formed integrally with the first beam and the second beam, respectively, including the connecting portion.

Further, preferably, the first beam and the second beam are elastically deformed in the first direction and the second direction, respectively. It may be supported in the middle.

In the piezoelectric actuator according to the present invention, the first support is fixed to one end of the substrate, and the third support is fixed to the other end of the substrate. The second support portion is provided in a movable state between the third support portion, the piezoelectric element is supported at both ends between the second support portion and the third support portion, and the displacement of the piezoelectric element is reduced. Directly transmitted to the beam.

Further, a first support portion and a second support portion are fixed to both sides of the substrate via hinge portions,
The piezoelectric element may be supported at both ends between the beam support ends and opposite ends of the two support portions, and the displacement of the piezoelectric element may be enlarged and transmitted to the beam.

[0015]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a first embodiment of the present invention.
(A), (b) and (c) are shown. A first support portion 1 and a third support portion 3 are formed on the substrate 101, and a second support portion 2 is movably provided between the support portions 1 and 3.

A piezoelectric element E is supported between the second support part 2 and the third support part 3 at both ends by the second support part 2 and the third support part 3. The piezoelectric element E expands and contracts in accordance with the voltage applied to the electrode, and its length increases from several microns to several tens of microns by applying the voltage.

Between the first support 1 and the second support 2, one end 4a is connected to the first support 1 and the other end 4b is connected to the second support 2.
The beam 4 is supported at both ends in a state where the beam 4 is fixed to the support portions 2. The beam 4 is plastically deformed (cursed) in a convex direction in such a manner that the beam 2 is deformed into an arc shape in a certain direction by moving the second support portion 2 toward the first support portion 1.

Here, as a method of deforming the beam 4 in a certain direction, in addition to plastically deforming the beam 4 so as to be convex in that direction, as described above, both support portions at both ends of the substrate 101 are used. When the piezoelectric element E and the beam 4 are attached between the first and third support portions 2 and the beam 4 is attached in a state where the beam 4 is elastically deformed so as to be convex in a certain direction. The second support 2
Can be deformed in an arc in a certain direction by moving to the first support portion 1 side.

The beam 4 is provided with a lever 5 extending in a direction of movement of the second support 2 from a portion deformed by the movement of the second support 2, and the extension end 5 a of the lever 5 is free. At the end.

In this embodiment, the beam 4 is formed of a plate-like member, and the lever 5 is provided with a U-shaped punched hole 4c in the beam 4 so that the lever 4 can be integrated with the beam 4 from the extension base 5b. Is formed. The beam 4 is provided with punched holes 4d, 4e, and 4f, so that these portions are easily deformed in an arc shape.

Next, the operation of the first embodiment will be described. FIG. 1B shows a state in which no voltage is applied to the piezoelectric element E, and the end surface 2a of the second support 2 on the first support 1 side is at the position T ₀ in this state. Although the beam 4 is substantially planar, the first support portion 1 and the second support portion 2 are plastically deformed or slightly elastically deformed upward as described above. Both ends are supported between. Here, in FIG. 1B, a state where the beam 4 is upwardly convex due to plastic deformation or elastic deformation is exaggerated for explanation. Thus, stretching the tip portion 5a of the lever 5 is located at substantially the same height as the reference height P ₀ of the beam 4.

FIG. 1C shows a state in which a voltage is applied to the piezoelectric element E. When a voltage is applied to the piezoelectric element E, the piezoelectric element E expands, and the second support 2 moves to the first support 1 side. That is, the end surface 2a of the second support 2 on the first support 1 side moves from T ₀ to T _{1 on the} left by t. As a result, the beam 4 is deformed in an upwardly convex arc shape with the vicinity of the punched hole 4e as the maximum displacement position. Beam 4
4g are punched holes 4d, 4e, 4f
Since the rigidity is higher than the rigidity, the displacement amount is small, and the lever 5 is displaced according to the non-punched hole 4g. Therefore, the extension end portion 5a of the lever 5 obtains a displacement amount enlarged with respect to the displacement amount of the punched hole portion 4e, and obtains the reference height P _{0 of the} beam 4.
P only displaced upward until the displacement height P ₁ against. Therefore, the extension tip 5a of the lever 5 is used as a point of action as a piezoelectric actuator. In FIG. 1C, similarly to FIG. 1B, the deformed state of the beam 4 is exaggerated for explanation.

Here, the displacement of each part of the beam 4 is actually a curve, but as shown in FIG. 2, the deformation of each part is simplified and considered as a straight line. The bending point is defined as a point U, the length of the lever 5 is L _a , the effective length of the non-punched hole 4g is L ₂ , the length from the U point to the end face 2a of the second support 2 is L ₁ , The displacement amount of the element is t,
Assuming that the displacement amount of e from the reference height P ₀ is h and the displacement amount of the extension end portion 5a of the lever 5 is p, h and p are approximated as follows.

[0024] _{h = L 1 · sin (θ} 1) p = h + L a · sin (θ 2) ^{_{However, θ 1 = cos -1 [(}} L 1 + L 2 -t) 2 + L 1 2 -L ^{_{2 2] / [2 · L}} 1 · (L 1 + L 2 -t)] θ 2 = cos -1 [(L 1 + L 2 -t) 2 + L 2 2 -L 1 2] / [2 · L ₂ · (L ₁ + L ₂ -t)] For example, if L ₁ = L ₂ = L _a = 10 (mm) and t = 0.01 (mm), h ≒ 0.32 (mm), p ≒ 0.63 ( mm). That is, the displacement amount p of the extension end portion 5a of the lever 5 is about twice as large as h and about 63 times as large as the displacement amount t of the piezoelectric element E.

Further, L ₁ = L _a = 14 (mm), L ₂ = 6 (mm), t
= 0.01 (mm), h ≒ 0.29 (mm) and p ≒ 0.97 (mm).

Further, the displacement amount of the beam 4, that is, θ ₁
Or within a tolerance of θ _2, L _1> by the _{L 2, L 2 <L a} , it is possible to increase the magnification.

The above calculation of h and p is an ideal case in which the beam 4 is deformed from a completely horizontal state. In practice, in the initial state, that is, the state shown in FIG. Since it has already been deformed so as to be slightly upwardly convex, to be precise, the magnification is smaller than this. Specifically, for example, when the beam 4 is t =
From the same state as when compressed by 0.001 (mm), t = 0.01 (m
The displacement when changing to m) is as follows. Displacement Δp = [p] t = 0.011− [p] t = 0.001 For example, if L ₁ = L ₂ = L _a = 10 (mm), displacement Δp
≒ 0.63-0.2 = 0.43 (mm). Therefore, the larger the deformation at the beginning, the smaller the magnification finally becomes, that is, the smaller the amount of displacement of the extension end portion 5a of the lever 5 becomes.

The rigidity of the lever 5 may be reinforced by applying a rigid member from the non-punched hole 4 g of the beam 4 to the lever 5.

In the first embodiment, the beams 4h, 4i of the beam 4 are provided on both sides of the lever 5, but only one of the beams 4h, 4i is used. Is also possible.

Next, FIGS. 3 (a), 3 (b) and 3 (c) and FIG. 4 show a second embodiment of the present invention. 3 (b) and 3 (c), a first beam and a second beam, which will be described later,
The thickness of the first and second levers is omitted and drawn with straight lines.

In the second embodiment, a substrate 101, a substrate 101
A first support part 1 and a third support part 3, a second support part 2 movably provided between the two support parts 1, 3, and a second support part 2. The piezoelectric element E supported at both ends between the third support portion 3
This is similar to that of the embodiment.

In contrast to the beam 4 of the first embodiment, in the second embodiment, one end 14a is provided between the first support 1 and the second support 2 at one end 14a. In the state where the other end 14b is fixed to the second support portion 2, the first beam 1
The second beam 16 is fixed to the first support portion 1 at one end 4 and the second beam 16 is fixed to the second support portion 2 at the other end 16b. First beam 1
4 is plastically deformed (hased) convexly in a certain direction so that the second support 2 is deformed into an arc in a certain direction by moving to the first support 1 side. Second
The beam 16 is plastically deformed (cursed) convexly in a certain direction so that the second support 2 moves toward the first support 1 so as to be deformed in an arc in a certain direction.
In the present second embodiment, the first beam 14 is deformed upward and the second beam 16 is deformed downward.

Here, as a method of deforming the first beam 14 and the second beam 16 in the respective fixed directions,
Similarly to the first embodiment described above, it is also possible to attach them in a state where they are elastically deformed so as to be convex in a certain direction.

The first beam 14 is provided with a first lever 15 rotatably via a connecting portion 14c at a portion which is deformed by the movement of the second support portion 2. The one extending tip 15a is a free end, and the other extending tip 15b is a second extending tip 15b described later.
The lever 17 is slidably coupled to each other by the extension end portion 17b of the lever 17 and the coupling member 18.

The second beam 16 is provided with a second lever 17 rotatably via a connecting portion 16c at a portion that is deformed by the movement of the second support portion 2. One extension tip 17a of the lever 17 is fixed to the second support portion 2 at the same height position as the one end 16b of the second beam 16, and the other extension tip 1
Reference numeral 7b is slidably connected to the extending distal end 15b of the first lever 15 described above.

In this embodiment, the first beam 14 and the second beam 16 are composed of plate-like members as in the first embodiment.

Note that the first beam 14 and the second beam 16 are drawn with different widths in FIG. 3A, but this is for the sake of simplicity of explanation for the sake of explanation. I do not care. Also, the first lever 1
5 and the second lever 17 are also shown in FIG.
Are drawn with different widths in order to make each lever easy to see for the sake of explanation, and may have the same width in practice.

Next, the operation of the second embodiment will be described. FIG. 3B shows a state in which no voltage is applied to the piezoelectric element E, and the end surface 2a of the second support 2 on the first support 1 side is at the position T ₀ in this state. Although the first beam 14 is substantially planar, the first support portion 1 and the second support portion 2 are plastically deformed so as to be slightly upwardly convex or elastically deformed as described above. Both ends are supported between the supporting portion 2. The second beam 16 is also substantially planar, but is plastically or elastically deformed so as to be slightly convex downward as described above. 2 between the two supporting portions 2. Here, in FIG. 3B, a state where the first beam 14 and the second beam 16 are convex upward or downward due to plastic deformation or elastic deformation is exaggerated for the sake of explanation. Therefore, the extension end portion 15a of the first lever 15 is located at substantially the same height as the reference height Q ₀ of the first beam 14.

FIG. 3C shows a state in which a voltage is applied to the piezoelectric element E. When a voltage is applied to the piezoelectric element E, the piezoelectric element E expands, and the second support 2 moves to the first support 1 side. That is, the end surface 2a of the second support 2 on the first support 1 side moves from T ₀ to T _{1 on the} left by t. As a result, the first beam 14 is deformed in an arc shape convex upward with the point V, which is the bending point, as the maximum displacement position, and the second beam 16 also moves the point W, which is the bending point, to the maximum displacement position. As a result, it is deformed downward and convexly into an arc. At this time, since the first lever 15 is connected to the first beam 14 via the connecting portion 14c, the first lever 15 is also connected to the connecting portion 14c.
Is deformed upward by the same amount as the displacement of the connecting portion 14c of the first beam 14, and the second lever 17 is also connected to the second beam 16 via the connecting portion 16c. The second lever 17 also deforms the connecting portion 16c downward by the same amount as the displacement of the connecting portion 16c of the second beam 16. Therefore, one extension tip 17a of the second lever 17 is fixed to the second support portion 2 at the same height position as one end 16b of the second beam 16, and the other extension tip 17b is the second extension tip 17b. Extension end 1 of lever 15
5b and the connecting member 18 are slidably connected to each other, so that the downward movement of the extending end 17b of the second lever 17 causes the extending end 15b of the first lever 15 to move downward.
Is also displaced downward, so that the extension end portion 15a of the first lever 15 obtains an enlarged amount of displacement centered on the connecting portion 14c to obtain a reference height Q ₀ of the first beam 14. Made Hen'i height Q ₁ is displaced upward by q. Therefore, the extension end portion 15a of the first lever 15 is used as a point of action as a piezoelectric actuator. 3 (c) and FIG. 4, as in FIG. 3 (b), the state where the first beam 14 and the second beam 16 are displaced is exaggerated for explanation.

Here, similarly to the above-described first embodiment, the displacement of each part of the first beam 14 and the second beam 16 is actually a curve, but as shown in FIG. The deformation of each part will be simplified and considered as linear. First
The bending points of the beam 14 and the second beam 16 are V point and W point, respectively, and the left and right lengths from the V point and the W point are L ₂ and L ₁ , respectively, and the left and right sides of the first lever 15 from the V point. Are the lengths L _b and L _a , respectively, the displacement of the piezoelectric element is t, the displacement of the V point or the W point from the reference height Q ₀ is h, and the displacement of the extension tip 15a of the first lever 15 is Let q be h
And q are approximated as follows:

[0041] _{h = L 1 · sin (θ} 1) q = h + L a · sinα ^{_{However, θ 1 = cos -1 [(}} L 1 + L 2 -t) 2 + L 1 2 -L 2 2] / [2 · L ₁ · (L ₁ + L ₂ -t)] θ ₂ = cos ^-1 [(L ₁ + L ₂ -t) ² + L ₂ ² -L ₁ ² ] / [2 · L ₂ · ( L ₁ + L ₂ -t)] α = sin ^-1 [[2 · L ₁ · sin (θ ₁ ) + K · tan (θ ₁ ) / L _b ]] K = [− B + (B ² -4)・ A ・ C) ^1/2 ] / (2 ・ A) A = 1 + [tan (θ ₁ )] ² B = 4 ・ L ₁・ sin (θ ₁ ) ・ tan (θ ₁ ) C = 4 ・ L ₁ ² · [sin (θ ₁ )] ² −L _b ² For example, if L ₁ = L ₂ = L _a = L _b = 10 (mm) and t = 0.01 (mm), h ≒ 0.32 (mm) , Q ≒ 1.26 (mm). That is,
The displacement q of the extension end portion 15a of the first lever 15 is about four times h and about 126 times the displacement t of the piezoelectric element E.

L ₁ = L _a = 14 (mm), L ₂ = L _b = 6 (m
m) (the total length of the first beam 14 and the second beam 16 is the same), if t = 0.01 (mm), h ≒ 0.29 (mm),
q ≒ 1.97 (mm), the extension end 1 of the first lever 15
The magnification of the displacement q of 5a is about 6.8 times of h and about 1 of t.
97 times.

Further, by increasing L ₁ / L ₂ and L _a / L _b within the allowable range of the displacement of the first beam 14 and the second beam 16, ie, θ ₁ or θ ₂ ,
The magnification can be increased.

The above calculation of h and q is an ideal case in which the first beam 14 and the second beam 16 are deformed from a completely horizontal state, and is actually an initial state, that is, FIG. ), Each beam 14,
16 is already slightly deformed so as to protrude upward and downward, so that the enlargement magnification is accurately smaller than this. Specifically, for example, the displacement amount when changing from t = 0.01 (mm) to t = 0.01 (mm) from the same state where each beam is compressed upward and downward by t = 0.001 (mm) is as follows. Displacement △ q = [q] t = 0.011− [q] t = 0.001 For example, if L1 = L2 = La = Lb = 10 (mm), displacement △ q ≒ 1.32-0.4 = 0.92 (mm) Become. Therefore, the larger the initial deformation, the smaller the enlargement magnification, that is, the smaller the amount of displacement of the extension end portion 15 a of the first lever 15.

The rigidity of the first lever 15 and the second lever 17 may be reinforced by a procedure such as attaching a rigid member to each of the levers 15, 17.

In the second embodiment, the first
Beam portions 14d of the first beam 14 on both sides of the lever 15
14e, the beams 14d, 14e
It is also possible to configure only one of them.

In the second embodiment, the second
Regarding both extension tip portions 17a, 17b of the lever 17,
The first lever 17a is fixed to the second support part 2 and the other distal end 17b is slidably coupled to the first distal end 15b of the first lever 15 so that the first lever 17a is extended. The extension of the extension tip 15a of the first lever 15 is slidably connected to the extension tip 15a of the first lever 15 and the other extension 17a. By fixing the distal end portion 17b to the first support portion 1, the displacement of the extending distal end portion 15b of the first lever 15 can be enlarged, that is, the position at which the displacement is enlarged can be changed.

In the first and second embodiments described above, the displacement of the piezoelectric element E is directly transmitted to the beam 4 or the first beam 14 and the second beam. Therefore, the displacement of the piezoelectric element E may be expanded and transmitted to the beam 4 or the first beam 14 and the second beam.
(B).

First, FIG. 6A will be described. A first support 21 and a second support 22 are provided on both sides of the substrate 102 via a hinge 29. One ends 21b and 22b of the first support 21 and the second support 22
Between them, a piezoelectric element E is supported via a hinge portion 29. Then, the beam 4 described in the first embodiment is applied between the piezoelectric element E and the opposite ends 21a and 22a of the support elements 21 and 22 opposite to the piezoelectric element E support ends 21b and 22b.
2 are provided so as to be located. The beam 4 is the same as in the first embodiment.

Next, FIG. 6B will be described. FIG.
As in (a), the first supporting portions 2 are provided on both sides of the substrate 102.
The first and second support portions 22 are provided via a hinge portion 29, and the piezoelectric element E connects the hinge portion 29 between one ends 21b and 22b of the first support portion 21 and the second support portion 22. Supported through. Then, the opposite ends 21a, 22 of the piezoelectric element E support ends 21b, 22b of both support portions 21, 22 are provided.
7A, the first beam 14 and the second beam 16 described in the second embodiment are provided so that the substrate 102 is positioned between the first beam 14 and the second beam 16. The first beam 14 and the second beam 16 are the same as in the second embodiment described above.

In operation, when the length of the piezoelectric element E is extended by the application of a voltage, the piezoelectric element E supporting ends 21b and 22b of the first supporting portion 21 and the second supporting portion are opposite to the opposite ends 21b.
a, 22a are displaced in directions approaching each other. At this time, the displacement of the piezoelectric element E is enlarged. Thereafter, similarly to the first and second embodiments, the beam 4 or the first
Beam 14 and second beam 16 are deformed into an arc shape,
The extension tip 5a of the lever 5, which is the point of action, or the first
Of the lever 15 is displaced.

In each embodiment of the present invention, an example has been described in which one action point is provided for one piezoelectric actuator. However, the present invention is not limited to this. For example, in the first embodiment, a plurality of beams 4 By providing them, it is possible to provide a plurality of action points on one piezoelectric actuator. This is applicable to the second embodiment and others. In addition, the plurality of action points provided on one piezoelectric actuator are not limited to those that perform the same operation, and can be driven in respective set directions, for example, in opposite directions. Further, for example, in the first embodiment, by providing an angle to the lever 5 provided on the beam 4, it is possible to freely set the angle for the operation of the action point. This is also the second
The embodiments described above and others can be applied.

[0053]

According to the present invention, a lever extending from a beam displacement portion and having a free end of the extending end as an action point is formed in a U-shape on the beam.
Formed integrally with the beam by providing a punched hole
By providing by a simple structure with a high rather displacement magnification, also be produced simply by pressing
Thus, a piezoelectric actuator that can be operated is obtained.

[0054] Then, in order to deform the bi over beam into a certain direction, by which is supported in a state of plastic deformation or elastic deformation in its constant direction, achieved without the need for special configuration in order that it can.

Further, by providing the second beam and the second lever for expanding the displacement of the first lever in cooperation with the first beam for expanding the displacement of the first lever, the deformation of the beam is reduced. Even so, a large magnification can be obtained, which reduces material fatigue due to deformation deformation of the beam. Also, if a deformation strain is applied as in the conventional case, the lever will obtain a larger displacement amount than in the conventional case.

The first beam and the first lever and the second beam and the second lever are composed of plate-like members, and the beam and the lever are integrally formed, so that they can be easily manufactured by press working. It is possible to do.

Further, in order to deform the first beam and the second beam in a certain direction, the first beam and the second beam are supported by being plastically or elastically deformed in the certain direction. Can be realized without need.

Further, the configuration for directly transmitting the displacement of the piezoelectric element can be adopted by the high displacement magnification.

Further, once the displacement of the piezoelectric element is enlarged and then transmitted to the beam or the first beam and the second beam, a higher displacement magnification can be obtained.

[Brief description of the drawings]

FIGS. 1A and 1B are diagrams showing a first embodiment, in which FIG. 1A is a plan view, FIG. 1B is a side view in which a voltage is not applied to a piezoelectric element, and FIG. It is a side view of the state performed.

FIG. 2 is a diagram for explaining a displacement enlargement magnification of the first embodiment.

FIGS. 3A and 3B are diagrams showing a second embodiment, in which FIG. 3A is a plan view, FIG. 3B is a side view in which a voltage is not applied to the piezoelectric element, and FIG. It is a side view of the state performed.

FIG. 4 is a side view showing a main part of the second embodiment.

FIG. 5 is a diagram for explaining a displacement enlargement magnification of the second embodiment.

6A and 6B are diagrams showing an embodiment in which the displacement of the piezoelectric element is transmitted while being enlarged, FIG. 6A is a diagram applied to the first embodiment, and FIG. 6B is a diagram applied to the second embodiment.

[Explanation of symbols]

 E Piezoelectric element 1 First support part 2 Second support part 3 Third support part 4 Beam 4c U-shaped punched hole (part) 5 Lever 5a Extension tip part 14 First beam 14c Connecting part 15 First 15a One end (extended tip) 15b One end (extended tip) 16 Second beam 16c Connecting portion 17 Second lever 17a Other end (extended tip) 17b One end (extended tip) 101 Substrate 102 Substrate

Continuation of the front page (56) References JP-A-59-177980 (JP, A) JP-A-61-50449 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02N 2 / 00

Claims (7)

(57) [Claims] A first support and a second support are provided so as to be able to reduce the distance between them by a piezoelectric element that expands and contracts in accordance with a voltage applied to an electrode. A beam that is elastically deformable in an arc in a certain direction is supported at both ends. The beam extends from a deformed portion of the beam in the moving direction of the two support portions, and has a free end at the extending end. Is provided, and the beam is formed of a plate-like member.
Has a U-shaped punched hole in the beam.
Wherein the piezoelectric actuator is formed integrally with the beam . 2. The beam according to claim 1, wherein the beam is elastically deformed in an arc in a predetermined direction, and is supported between the support portions in a state of being deformed to be convex in the predetermined direction. 2. The piezoelectric actuator according to 1 . 3. A first support portion and a second support portion are provided so as to be able to reduce the distance between them by a piezoelectric element which expands and contracts in accordance with a voltage applied to an electrode, and is provided between the two support portions. A first beam elastically deformable in an arc in a first direction and a second beam elastically deformable in an arc in a second direction opposite to the first direction are supported at both ends; The first beam is provided with a first lever rotatably at a deformed portion of the first beam via a connecting portion, and the second beam is provided with a deformation of the second beam. A second lever is rotatably provided at the portion via a connecting portion. One end of the first lever and one end of the second lever are slidably coupled to each other, and The other end of the second lever is supported by the second support similarly to the second beam, and The piezoelectric actuator the other end of the lever, characterized in that the point of action a free end. 4. The first beam and the second beam are formed of a plate-like member, and the first lever and the second lever each include a connecting part, and
4. The piezoelectric actuator according to claim 3 , wherein the piezoelectric actuator is formed integrally with the first beam and the second beam. 5. The first beam and the second beam are elastically deformed in the first direction and the second direction, respectively. Claims characterized by being supported between parts
5. The piezoelectric actuator according to 3 or 4 . 6. The first support portion is fixed to one end of the substrate, and the third support portion is fixed to the other end of the substrate, and the first and third support portions are fixed to each other. In between the second
The support portion is provided in a movable state, claim 1, characterized in that the piezoelectric element is supported at both ends between the second support portion and the third supporting portion or
Or the piezoelectric actuator according to 3 . 7. The first support portion and the second support portion are fixed to both sides of a substrate via hinges, and a piezoelectric element is provided between the beam support end and the opposite end of the two support portions. the claim 1, characterized in that the element is supported at both ends
Is the piezoelectric actuator according to 3 .