JP4141703B2 - Variable structure actuator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a so-called intelligent structure system in which a solid actuator of a distributed system is incorporated in a structure to reduce shape and vibration and noise. The present invention relates to a variable structure actuator having a displacement expansion function that compensates for the shortage.
[0002]
[Prior art]
In recent years, a so-called knowledge that a distribution system sensor or actuator has been incorporated into a structure to detect the vibration or deformation of the structure caused by disturbances and control the vibration and shape of the structure using the detected information. Research and development of dynamic structural systems is actively conducted.
[0003]
In the development of sensors, the progress of health monitoring technology that makes it possible to detect cracks and identify damaged locations by embedding small-diameter optical fiber sensors in structures is particularly remarkable. In addition, a technique for monitoring the vibration distribution of a thin plate using an inexpensive film sensor that can be cut into an arbitrary shape and attached to a structure has been developed.
[0004]
Sensor technology in such an intelligent structure system is extremely useful from the viewpoint of evaluating the structural integrity of satellites, aircraft, high-speed vehicles, high-rise buildings, etc., or from the viewpoint of controlling the vibration and shape of structures. It is important and is awaiting practical use.
[0005]
On the other hand, in the development of actuators in intelligent structural systems, in order to realize a system that optimizes the shape and reduces vibration and noise using sensors and actuators incorporated in structures, high-performance solid actuator materials and elements Development of optimal control system technology is necessary. Research into actuator materials and elements has been steadily advancing with the development of material processes such as wire rods, thin films, and gradient functions.
[0006]
[Problems to be solved by the invention]
By the way, in order to control the deformation of the structure by the intelligent structure system, the displacement amount (strain amount) of the actuator is often insufficient. In research on intelligent structural systems, there are many research examples using shape memory alloys and piezoelectric elements as actuator materials and elements. Conventionally, most actuators are used by attaching a sheet / wire-like element to a structure, and the deformation amount of the structure cannot exceed the displacement amount (strain amount) of the actuator.
[0007]
Vibration and acoustic power control can be controlled with a relatively small displacement, but the displacement (distortion) is particularly insufficient when controlling the deformation of the wing camber or the robot actuator in an aircraft. Therefore, the early development of actuator materials and elements that satisfy the demands is strongly expected. However, it takes a long time to develop actuator materials and elements, and dramatic improvements in performance cannot be expected in a short time.
[0008]
In general, the displacement of the piezoelectric element is only about 0.08% when converted to strain, and the operating strain of the shape memory alloy wire is generally about 2-3% (practical operation strain). It is. The shape memory alloy wire has a larger operating strain than the piezoelectric element, but it is not a satisfactory value, and a larger operating strain is desired.
[0009]
As a method for compensating for the shortage of the displacement amount (strain amount) of the actuator, a displacement enlargement mechanism using a lever has been well known. A typical conventional example is shown in FIG. The conventional example shown in FIG. 10 (Precision positioning technology, published by Industrial Research Co., Ltd., described on p45) is composed of an actuator arranged on a base and several stages of displacement enlargement mechanism. Accordingly, a large amount of displacement can be obtained. On the other hand, the generated force decreases according to the number of steps, and in the multi-stage mechanism, the structural rigidity is lowered.
[0010]
The present invention has been made in view of the above-described conventional situation, and an object of the present invention is to provide an actuator and a structure that are configured to make up for a lack of displacement (distortion) of the actuator by a structural device. Is to provide a variable structure actuator that is integrally distributed.
[0011]
[Means for Solving the Problems]
The present invention has been made in view of the conventional problems as described above. The invention according to claim 1 is such that both end portions can be displaced toward and away from each other, and an intermediate position between both end portions connects the both end portions. In a cell having a closed space in which the both ends of opposing movable pieces that can be displaced in a direction approaching and separating from a straight line are connected, the cell can be actively deformed in the extension direction, the reduction direction, or both directions. A solid actuator is arranged, and both ends of the solid actuator are connected to the positions of both ends of the movable piece or near the positions of both ends , and the movable piece is made of a thin plate that can be returned to its original state by elasticity. The solid actuator is made of a piezoelectric material, a shape memory alloy, or a magnetostrictive material processed into a film shape, a thin film shape, or a linear shape.
[0012]
According to a second aspect of the present invention, in the variable structure actuator according to the first aspect, a second solid actuator having an operation direction intersecting with an operation direction of the solid actuator is disposed in the cell. In this configuration, both end sides of the second solid actuator are respectively connected to the opposed movable pieces.
[0013]
According to a third aspect of the present invention, there is provided an opposed movable piece which can be displaced in a direction in which both end portions approach and separate from each other, and an intermediate position of the both end portions can be displaced in a direction in which the both end portions approach and separate from a straight line connecting the both end portions. Provided with a plurality of cells having a closed space in which the both ends are connected, and provided with a stretchable structure in a mode in which the plurality of cells are connected linearly or in a plane, and a desired cell in this structure A solid actuator that can be actively deformed is arranged in the extension direction, the reduction direction, or both directions, and both ends of the solid actuator are connected to both end positions of the movable piece or in the vicinity of both end positions . The movable piece is composed of a thin plate that can be returned to its original state by elasticity, and the solid actuator is a piezoelectric material, a shape memory alloy, or a magnetostriction processed into a film shape, a thin film shape, or a linear shape. It is made of a fee.
[0014]
According to a fourth aspect of the present invention, in the variable structure actuator according to the third aspect, a second solid actuator having an operation direction intersecting with the operation direction of the solid actuator is disposed in a desired cell. Both end sides of the second solid actuator are connected to the opposed movable pieces, respectively.
[0015]
According to a fifth aspect of the present invention, there is provided an opposed movable piece which can be displaced in a direction in which both end portions approach and separate from each other, and an intermediate position of the both end portions can be displaced in a direction in which the both end portions approach and separate from a straight line connecting the both end portions. A structure is provided in which a plurality of cells having a closed space in which both ends are connected are connected to each other and arranged in a cylindrical shape, and the desired cell in the structure has an extension direction, a reduction direction, or its direction. A solid actuator that can be actively deformed in both directions is arranged, and both ends of the solid actuator are connected to both end positions of the movable piece or in the vicinity of both end positions. The movable piece is restored to its original state by elasticity. The solid actuator is formed of a piezoelectric material, a shape memory alloy, or a magnetostrictive material processed into a film shape, a thin film shape, or a linear shape.
[0016]
According to a sixth aspect of the present invention, in the variable structure actuator according to any one of the first to fifth aspects, the displacement in the vicinity of the central portion of the movable piece is enlarged or reduced as compared with the operation displacement amount of the solid actuator. As described above, the solid actuator and the movable piece are connected at a predetermined angle.
[0017]
According to a seventh aspect of the present invention, in the variable structure actuator according to any one of the first to sixth aspects, the cell has a line-symmetric shape.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0020]
FIG. 1 is an explanatory view showing a basic structure of a variable structure actuator 1 according to an embodiment of the present invention. FIG. 1 (a) is a partially enlarged explanatory view of an internal cell, and FIG. It is explanatory drawing which showed the mode of the deformation | transformation of a cell.
[0021]
Basically, the variable structure actuator 1 can be displaced in a direction in which both end portions A and B approach and separate from each other, and intermediate positions C and D between the both end portions A and B are straight lines connecting the both end portions A and B. In the closed space 4 of the cell 21 having the closed space 4 in which both ends A and B of a pair of opposed movable pieces 2 and 3 that can be displaced in a direction approaching and separating from each other are connected, the expansion direction or reduction A solid actuator 6 that can be actively changed in one or both directions is disposed, and both ends of the solid actuator 6 are positioned at the positions of both ends A and B of the movable piece 2 or 3 or near the positions of both ends A and B. It is the structure connected to.
[0022]
More specifically, in the present embodiment, the closed space 4 is formed by appropriately combining a plurality (four in the present embodiment) of elastic structural thin plates (movable members) 21a, 21b, 21c and 21d. It is a parallelogram-shaped (quadrangular) space that is closed (upper and lower). And one movable piece 2 is comprised by the combination of elastic structure thin plate 21a, 21d, and the other movable piece 3 is comprised by the combination of elastic structure thin plate 21b, 21c.
[0023]
The pair of movable pieces 2 and 3 have a symmetric configuration, and both end portions A and B of the movable pieces 2 and 3 are connected to connecting portions of thin plates (movable members) 21a and 21b and thin plates (movable members) 21c and 21d. This corresponds to the connecting portion. Hinge portions C and D are provided at the center between the pair of movable pieces 2 and 3.
[0024]
The hinge part C corresponds to the connection part of the thin plates 21a and 21d, and the hinge part D corresponds to the connection part of the thin plates 21b and 21c. The hinge portions C and D are preferably a structure that can be easily bent. For example, an appropriate hinge structure such as a thin-walled structure or a structure in which an elastic member such as rubber is interposed can be employed. .
[0025]
In the above description, the thin plates 21a, 21b, 21c and 21d are described as being formed by combining the separate members to form the movable pieces 2 and 3, but each of the thin plates 21a, 21b, 21c and 21d has a quadrangular shape. It is good also as a hinge structure which shape | molds integrally so that each side of the cell 21 may be comprised previously, and both ends A and B and hinge part C and D can be bent. Moreover, each side member (namely, each thin plate 21a-21d) which comprises the cell 21, and each corner | angular part (namely, edge part A, B, so that the some cell 21 can be combined linearly and / or planarly. It is also possible to provide a connecting part such as an unevenness in the hinge part C, D) or the like.
[0026]
As will be understood from the above description, when the both end portions A and B of the cell 21 are displaced so as to approach each other, the hinge portions C and D at the intermediate positions are displaced so as to be separated from each other. , B are moved away from each other, the hinge parts C, D are displaced so as to approach each other. At this time, the inner angles of both ends A and B of the cell 21 having a quadrangular shape are made acute and the inner angles of the hinges C and D, which are intermediate portions, are made obtuse, thereby approaching both ends A and B. Compared to the amount of displacement in the direction of separation, the amount of displacement in the direction in which the hinge portions C and D approach and separate can be made larger. Therefore, in order to displace both end portions A and B of the cell 21 in the approaching or separating directions, a solid actuator 6 is disposed in the closed space 4 of the cell 21, and both end sides of the solid actuator 6 are connected to the both end portions. A, B or both ends A, B are connected.
[0027]
The solid actuator 6 is made of, for example, a piezoelectric material, a shape memory alloy, a magnetostrictive material, or the like processed into a film shape, a thin film shape, or a linear shape, and in the present embodiment, a strip shape memory alloy is used. It is illustrated as a configuration that shrinks when energized and heated.
[0028]
Therefore, when the solid actuator 6 is operated to displace the both end portions A and B so as to approach each other, the thin plates 21a, 21b, 21c and 21d are elastically deformed so as to be bent at the hinge portions C and D, respectively. As shown in (b), the hinge portions C and D are greatly displaced in directions away from each other. The return to the original state is performed by the elasticity of the thin plates 21a, 21b, 21c and 21d.
[0029]
At this time, in order to perform the return operation of the cell 21 more reliably, the cell 21 is operated in a direction crossing the operation direction of the solid actuator 6, that is, an operation of displacing the hinge portions C and D in the approaching direction. It is desirable to provide a solid actuator 7 to perform. In this case, as shown in FIG. 2, the solid actuator 6 and the solid actuator 7 are provided so as to intersect with each other, and both ends of the solid actuator 7 are connected to the hinge portions C and D or the vicinity of the hinge portions C and D. It is good.
[0030]
In the above configuration, when one solid actuator 6 is operated in the direction of reducing, the other solid actuator 7 is extended through the thin plates 21a to 21d, and conversely, the other solid actuator 7 is reduced. When it is operated in the direction, the one solid actuator 6 is extended. That is, the operation direction of one solid actuator 6 and the other solid actuator 7 is always reversed.
[0031]
FIG. 3 shows a variable structure actuator 20 having a configuration in which the cells 21 having the above-described configuration are arranged in a plurality of columns and a plurality of rows. As shown conceptually in FIG. 1A, the variable structure actuator 20 as described above is composed of a plurality of strip-like elastic structural thin plates 21a, 21b, 21c, and 21d in the form of a cross-beam, and a plurality of these formed It is obtained by combining a plurality of solid actuators 22 (22a, 22b, 22c) so as to connect the diagonals of the quadrangular cells 21.
[0032]
As can be understood from FIG. 3, the variable structure actuator 20 has a configuration in which parallelogram-shaped cells 21 are continuously arranged in four directions and are integrally disposed with a planar spread, and in this embodiment, parallel. A matrix structure having four sides of the four-sided cells 21 in the horizontal direction and 10 levels in the vertical direction is formed. The solid actuator 22b is integrally coupled to the cell 21 at a position connecting the intersection A of the elastic structural thin plates 21a and 21b and the intersection B of the elastic structural thin plates 21c and 21d with a straight line. Similarly, the solid actuators 22a and 22c are elastic structural thin plates. The intersection C of 21a and 21d and the intersection D of the elastic structure thin plates 21b and 21c are integrally and continuously coupled to the intersection of the elastic structure thin plates of the adjacent cells 21 to form the variable structure actuator 20. .
[0033]
Here, for example, the angles formed by the two sides of the elastic structural thin plates 21a and 21b and 21c and 21d (inner angles of both end portions A and B) are 30 degrees, and the elastic structural thin plates 21a and 21d and 21b and 21c are 2 respectively. When the angle formed by the sides (inner angles of the hinge portions C and D) is set to 150 degrees and the dimension between the intersections is (λ1, γ1) as shown in FIG. 1, the solid actuator 22b is obtained by energization heating. The output displacement (strain: (λ 2 −λ 1) / λ 1) of the variable structure actuator 20 in the direction perpendicular to the contraction displacement (strain: (γ 1 −γ 2) / γ 1) can be enlarged about twice. .
[0034]
That is, the amount of displacement at the intermediate positions C and D can be greatly increased compared to the amount of displacement at both ends A and B due to the displacement of the solid actuator. Therefore, by providing a plurality of cells 21 in the same direction, it is possible to further multiply the amount of displacement and obtain a large displacement.
[0035]
FIG. 4 is a diagram for explaining the configuration of the second variable structure actuator 30 based on the basic principle of the present invention. The basic arrangement is the same as that of the variable structure actuator 20 shown in FIG. 3 except that the cells 31 forming the structural system are not parallel quadrilateral but hexagonal. By integrally combining the matrix structure having the plurality of hexagonal cells 31 in the vertical and horizontal directions and the solid actuator 32 such as a plurality of strip-shaped shape memory alloys processed into a sheet shape, The variable structure actuator 30 is configured.
[0036]
The variable structure actuator 30 using the hexagonal cell 31 can increase the strength and rigidity of the structure as compared with the variable structure actuator 20 using the quadrangular cell 21.
[0037]
As already understood, the shape of the cell is not limited to a quadrangular shape, but can be formed in a hexagonal shape, and can be formed in other polygonal shapes. It is also possible to have a shape exhibiting a curved curve such as the above. In short, any structure may be used as long as the closed space includes a component corresponding to both ends and a portion displaced in the intersecting direction corresponding to the displacement of the both ends toward and away from each other.
[0038]
In the above description, the case where cells having the same shape are arranged vertically and horizontally has been described. However, a configuration in which a plurality of cells having different shapes is arbitrarily combined may be employed.
[0039]
FIG. 5 is a view for explaining an example of a manufacturing method of the variable structure actuator 20.
[0040]
As a method of manufacturing the variable structure actuator 20 shown in FIG. 3, it is possible to individually arrange solid actuators in a parallelogram cell, but it is desirable to adopt the method shown in FIG. . That is, the movable piece 2 is formed by bending and alternately providing strip-shaped solid actuators 22a and elastic structural thin plates 21a and 21d, and the cell thin plate member 23a having the movable piece 2 continuously provided, The following strip-shaped solid actuator 22b and elastic structure thin plates 21b and 21c are bent and alternately provided to form the movable piece 3, and the cell thin plate member 23b having a configuration including the movable piece 3 continuously, Further, after the next strip-shaped solid actuator 22c is individually manufactured, a sandwich in which the solid actuator 22a, the cell thin plate member 23a, the solid actuator 22b, the cell thin plate member 23b, and the solid actuator 22c are stacked in this order using a known fixing means. The structure is integrally formed. Furthermore, the number of parts to be sandwiched is increased as necessary, and the size is produced in accordance with the purpose.
[0041]
FIG. 6 shows an example of a manufacturing method of the variable structure actuator 30 shown in FIG. The variable structure actuator 30 is also provided with a plurality of strip-shaped solid actuators 32 and predetermined trapezoidal portions corresponding to the hexagonal cells 31 alternately using the same method as the manufacturing method of the variable structure actuator 20. It is constituted integrally by a sandwich structure in which the cell thin plate members 33 made of elastic corrugated thin plates are alternately stacked.
[0042]
FIG. 7 is a view for explaining the configuration of the third variable structure actuator 40 based on the basic configuration of the present invention. The variable structure actuators 20 and 30 described above have a planar configuration. However, the variable structure actuator 40 is hollow, for example, has a hollow hexagonal prism-shaped rod structure, and each surface of the hollow hexagonal prism shape {circle around (1)}. ˜6 are different in that the elastic structure thin plates 21 a to 21 d and the solid actuators 22 a to 22 c shown in the variable structure actuator 20 are formed in a linear shape, and the overall structure is formed in a cylindrical shape. In this configuration, the output displacement can be obtained so as to expand and contract in the axial direction of the structure. In addition, the overlapping description is abbreviate | omitted as attaching | subjecting the same code | symbol to the component which show | plays the same function.
[0043]
FIG. 8 shows a configuration example in which the variable structure actuator 40 of the present invention is applied to blade deformation. The variable structure actuator 40 is installed so as to intersect at two locations inside the blade, and the camber is controlled by the axial deformation of the rod-shaped variable structure actuator 40. In addition, although this figure is the structure described in Proc.SPIE Vol.3985-11, it was the structure which used the shape memory alloy wire conventionally. Here, by using the variable structure actuator 40 in place of the shape memory alloy wire, it is possible to achieve greater blade deformation and improve rigidity. This leads to an increase in steering force, and an improvement in aircraft performance can be expected.
[0044]
FIG. 9 shows a configuration example in which the rod-shaped variable structure actuator 40 is applied to an actuator for swinging a robot arm. The conventional general configuration uses, for example, a shape memory alloy wire 50 as a drive source. Here, the operation range can be expanded by using the variable structure actuator 40 instead of the shape memory alloy wire. Moreover, the improvement of the rigidity as a structure can be expected.
[0045]
【The invention's effect】
As will be understood from the above description, according to the present invention, the solid actuator and the structure are integrally distributed and the displacement of the actuator (by the elastic deformation of the cells inside the structure) Since the displacement is enlarged so as to compensate for the lack of (strain amount), it is possible to contribute to solving the problem that the displacement amount (strain amount) is small in the conventional actuator. In addition, the integration of the solid actuator and the structure allows for a compact, lightweight and highly rigid design, and is easy to embed in various devices.
[0046]
Therefore, if the variable structure actuator according to the present invention is applied to, for example, an aircraft wing camber control or a robot actuator, in the wing camber control, a steering force increases due to a large wing deformation, and an improvement in aircraft motion performance can be expected. . In addition, the robot actuator can be expected to expand its operating range while suppressing the decrease in rigid body as a structure. This provides an innovative actuator structure system for aircraft wing camber control and robot actuators, and can greatly contribute to downsizing and energy saving of the device.
[Brief description of the drawings]
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an explanatory diagram for explaining a basic configuration of a variable structure actuator according to an embodiment of the present invention, in which (a) is a partially enlarged view of an internal cell, and (b) is a cell with respect to an operation displacement of the actuator. It is the figure which showed the mode of deformation | transformation.
FIG. 2 is an explanatory diagram including a solid actuator in a direction intersecting with a variable structure actuator.
FIG. 3 is an overall view of a variable structure actuator before deformation and an explanatory view showing a state of deformation;
FIG. 4 is a diagram for explaining a configuration of a variable structure actuator according to a second embodiment of the present invention.
FIG. 5 is a diagram for explaining a manufacturing method of a variable structure actuator in the present embodiment.
FIG. 6 is a diagram for explaining a manufacturing method of a variable structure actuator according to a second embodiment.
FIG. 7 is a diagram for explaining a configuration of a variable structure actuator according to a third embodiment of the present invention.
FIG. 8 is a diagram showing an application example of the variable structure actuator in the third embodiment of the present invention to blade deformation control.
FIG. 9 is a diagram showing an application example of a variable structure actuator to a robot actuator according to a third embodiment of the present invention.
FIG. 10 is a configuration explanatory view of a lever-type displacement enlarging mechanism using a conventional lever.
[Explanation of symbols]
1, 20, 30, 40 Variable structure actuator 21, 31 Cell 21a, 21b, 21c, 21d Elastic structure thin plate (movable member)
22, 22a, 22b, 22c, 32 Solid actuator (shape memory alloy)
23a, 23b, 33 cell thin plate member

Claims (7)

The both ends of the movable pieces opposed to each other can be displaced in a direction in which both end portions approach and separate from each other, and an intermediate position of the both end portions can be displaced in a direction approaching and separating from a straight line connecting the both end portions. In a cell having a closed space, a solid actuator that can be actively deformed in the extension direction, the reduction direction, or both directions is arranged, and both ends of the solid actuator are positioned at both ends of the movable piece or near both ends. The movable piece is formed of a thin plate that can be returned to its original state by elasticity, and the solid actuator is a piezoelectric material or shape memory alloy processed into a film shape, a thin film shape, or a linear shape, or A variable structure actuator comprising a magnetostrictive material .   2. The variable structure actuator according to claim 1, wherein a second solid actuator having an operation direction intersecting with an operation direction of the solid actuator is disposed in the cell, and both end sides of the second solid actuator are disposed. Are each connected to the opposed movable pieces. The both ends of the movable pieces opposed to each other can be displaced in a direction in which both end portions approach and separate from each other, and an intermediate position of the both end portions can be displaced in a direction approaching and separating from a straight line connecting the both end portions. A plurality of cells having a closed space are provided, and an expandable structure having a form in which the plurality of cells are connected linearly or in a plane is provided, and a desired cell in the structure has an extension direction or a reduction direction. Alternatively, a solid actuator that can be actively deformed is arranged in both directions, and both ends of the solid actuator are connected to or near both end positions of the movable piece. Yes constructed from returning freely sheet into a state, the solid actuator, characterized in that it consists of a piezoelectric material or a shape memory alloy or magnetostrictive material is processed into a film-like or thin film-like or linear Variable structure actuator.   4. The variable structure actuator according to claim 3, wherein a second solid actuator having an operation direction intersecting the operation direction of the solid actuator is disposed in a desired cell, and both ends of the second solid actuator are arranged. A variable structure actuator characterized in that a side is connected to each of the opposed movable pieces. The both ends of the movable pieces opposed to each other can be displaced in a direction in which both end portions approach and separate from each other, and an intermediate position of the both end portions can be displaced in a direction approaching and separating from a straight line connecting the both end portions. A structure in which a plurality of cells having a closed space are connected to each other and connected in a cylindrical shape is provided, and can be actively deformed in the expansion direction, the reduction direction, or both directions in a desired cell in the structure. A solid actuator is arranged, and both ends of the solid actuator are connected to both end positions of the movable piece or in the vicinity of both end positions. The movable piece is made of a thin plate that can be returned to its original state by elasticity. The variable actuator is characterized in that the solid actuator is made of a piezoelectric material, a shape memory alloy, or a magnetostrictive material processed into a film shape, a thin film shape, or a linear shape .   The variable structure actuator according to any one of claims 1 to 5, wherein the solid actuator and the solid actuator are arranged so that a displacement near a central portion of the movable piece is enlarged or reduced as compared with an operation displacement amount of the solid actuator. A variable structure actuator characterized in that the movable pieces are connected at a predetermined angle.   7. The variable structure actuator according to claim 1, wherein the cell has a line-symmetric shape.

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