JP2020126962A - Thin deformable panel out-of-plane deforming using auxetic structure - Google Patents

Abstract

To provide a thin deformable panel in which a mechanism for applying a force for out-of-plane deformation can be arranged along a surface in the vicinity of the surface.SOLUTION: The thin deformable panel includes: a thin substrate; a contraction element having a first end bonded to the thin substrate to selectively contract; and an auxetic structure plate having an auxetic structure extending in a second direction as well when extending in a first direction, in which at least one of a pair of second periphery edges is bonded to a second end of the contraction element, and at least a portion of an area between the periphery edge not bonded to the contraction element and a pair of first periphery edges is bonded to the thin substrate. When contracted by the contraction element, the auxetic structure plate and the thin substrate are subjected to integral out-of-plane deformation.SELECTED DRAWING: Figure 4

Description

The present invention relates to a thin deformable panel that can be used as a part or member in an arbitrary structure or the like, and more specifically, a thin plate having an auxetic structure can be used to actively perform out-of-plane deformation. It concerns a possible thin panel.

Generally, since the Poisson's ratio of a solid material is positive, when a member made of a solid material is elongated in one direction, it contracts in a direction perpendicular to that direction. However, there is also a structure with a negative Poisson's ratio called "auxetic structure", that is, when a member is stretched or stretched in one direction, a special structure is also stretched or stretched in a direction perpendicular to that direction. Various techniques related to such “auxetic structure” that can be formed have been proposed. For example, Patent Document 1 proposes a method of manufacturing a composite material, which achieves a state of exhibiting a negative Poisson's ratio by arranging two kinds of linear elements having different elastic moduli in the composite material so as to cross each other. There is. Further, in Patent Document 2, an auxetic structure member is used in footwear, and shocks are absorbed by inputting an externally applied load or the like by utilizing the unique strain characteristic of the auxetic structure. A configuration has been proposed. In addition, Patent Document 3 discloses that a metal foam layer having a negative Poisson's ratio is used for an outer panel of an aircraft to avoid damage due to ice collision and reduce acoustic energy.

Japanese Patent Laid-Open No. 10-134102 Japanese Patent Laid-Open No. 2018-140230 Japanese Patent Laid-Open No. 2019-011039

By the way, when a planar structure or a panel-shaped member (hereinafter, referred to as “panel”) is to have various deformation functions, generally, a mechanism for applying a force for such deformation is additionally provided. It will be. For example, when the panel is out-of-plane deformed, as shown in FIG. 6, a mechanism (deformation force applying mechanism) Z for applying a force for deforming a cylinder, a motor, or the like to the panel is attached to the panel. It will be configured to be installed outside the plane. In such a case, as is clear from the figure, the space D for the deformation force applying mechanism is required, and this makes it possible to use such an out-of-plane deformable panel (machine tool Part of the structure) will be restricted. Therefore, if various deformation functions, especially out-of-plane deformation function, are applied to the panel, the deformation force applying mechanism is not installed outside the surface of the panel, and along the surface in or near the surface of the panel. If it can be arranged and the panel is so-called autonomously out-of-plane deformable, the available place of such out-of-plane deformable panel is expanded, and any mechanical device or structure Etc., it is expected that various structures or configurations not previously seen can be achieved.

With regard to the configuration of the out-of-plane deformable panel as described above, the inventor of the present invention uses the special deformation characteristic of the auxetic structure as described in the section of "Prior Art" to obtain out-of-plane deformation. It has been found that it is possible to realize a configuration in which the deforming force applying mechanism of (1) is arranged in or near the surface of the panel along the surface. This finding is used in the present invention.

Thus, an object of the present invention is an out-of-plane deformable panel, in which the mechanism for applying the force for deformation can be arranged in-plane and/or near the plane along the plane. It is to provide a panel.

According to the present invention, the above problem is a thin deformable panel,
A thin substrate that can be deformed out of plane,
At least one contraction element, the first end is bonded on the thin substrate, the contraction element for selectively contracting between the first end and the second end,
An out-of-plane deformable auxetic structure plate is provided in a plane intersecting the first direction with a pair of first peripheral edges extending along the first direction in the plane and facing each other. Is surrounded by a pair of second peripheral edges extending along the second direction and facing each other, and having an auxetic structure that extends in the second direction when extended in the first direction, At least one of the pair of second peripheral edges is bonded to the second end of the contraction element, and at least a part of the area between the peripheral edge not bonded to the contraction element and the pair of first peripheral edges. Includes an auxetic structure plate bonded to the thin substrate,
Even if the contracting element contracts, the length from the first end of the contracting element to the second peripheral edge of the auxetic structure plate where the second end of the contracting element is not joined does not become short. As described above, the position of the first end of the contraction element is constrained, and the displacement amount of the distance between the pair of first peripheral edges of the auxetic structure plate is equal to that of the pair of first edges when the auxetic structure plate is extended. When the contraction element contracts in a state where the distance between the pair of first peripheral edges is constrained so as not to exceed the displacement amount of the length along the surface between the peripheral edges, the auxetic structure plate and the thin substrate Is achieved by a thin deformable panel that is integrally deformed out of plane.

In the above, "out-of-plane deformation" means that the inner region of the thin plate member, that is, the thin substrate and the auxetic structure plate, is in the direction perpendicular to the surface direction relative to the peripheral edge thereof. It refers to a deformation that projects and displaces. The “thin substrate” is any elastic material (metal, resin, plastic, composite material) that has rigidity that can autonomously hold a planar structure (that is, does not use an external force) and can bend in an out-of-plane direction. , Paper, wood, etc.). The "shrink element" is an element that can be selectively shrunk, for example, an element formed of a shape memory alloy or a piezoelectric material, and formed in a strip shape or a strap shape that can be arranged along the surface of the thin substrate. Available components are available. As described above, the contraction element has the first end bonded to the thin substrate and extends along the thin substrate, and the second end bonded to the peripheral edge of the auxetic structure plate. The "auxetic structure plate" is a plate-shaped member having the above-mentioned deformation characteristics of the auxetic structure, and is any elastic material (metal, resin, plastic, composite material, paper, It may be made of wood or the like (preferably, it may have a rigidity capable of autonomously maintaining the planar structure, but it is not limited thereto). The peripheral edge which is not formed and at least a part of the region between the pair of opposing first peripheral edges are bonded to the thin substrate. In this regard, the retraction element may be bonded to both of the pair of second perimeters of the auxetic structure plate, in which case the retraction element may be coupled to the first perimeter of each of the second perimeters of the auxetic structure plate. Extending outward along the direction, each first end of the contraction element is bonded to the thin substrate, and a pair of opposing first perimeters of the auxetic structure plate are bonded to the thin substrate. .. Further, the contraction element may be configured to be bonded to only one of the pair of second peripheral edges of the auxetic structure plate, and in that case, the contracting element may be connected to the pair of opposing first peripheral edges of the auxetic structure plate. The second peripheral edge of the auxetic structure plate to which the contraction element is not bonded is bonded to the thin substrate. And in the above-mentioned structure, the length from the first end of the contraction element to the second peripheral edge of the auxetic structure plate where the second end of the contraction element is not joined is not shortened. If held, the auxetic structure plate will always extend parallel to the contraction direction of the contraction element when the contraction element contracts. The length from the one end to the second peripheral edge of the auxetic structure plate where the second end of the contraction element is not joined is not shortened, that is, when the contraction element contracts, the auxetic structure plate is When the contraction element is bonded to both sides of the pair of second peripheral edges of the auxetic structure plate so as to be surely extended, the distance between the first ends of the contraction elements on both sides is restricted. , Or if the contraction element is bonded to only one of the pair of second peripheral edges of the auxetic structure plate, the first end of the contraction element and the auxetic (to which the contraction element is not bonded) The position of the first end of the contraction element on the thin substrate is constrained so that the distance from the second peripheral edge of the structural plate is constrained, and the pair of first of the auxetic structural plates on the thin substrate is constrained. The part where the one peripheral edge is joined (becomes a linear region) has a distance between the parts along the surface between the pair of first peripheral edges of the auxetic structural plate when the auxetic structural plate is extended. Restrained to remain shorter than length.

According to the above configuration, since the joint portion of the contraction element on the thin substrate (or the joint portion of the second peripheral edge of the auxetic structure plate on the thin substrate) is constrained as described above, the auxetic structure When the contraction element contracts on either or both sides of the second perimeter of the plate, the auxetic structure plate is first stretched along the first direction. Then, due to the characteristics of the auxetic structure plate, the first peripheral edge of the auxetic structure plate is constrained so that the displacement is limited as described above, while the auxetic structure plate is extended along the second direction. The length along the surface between the first perimeters of the structure plate is longer than the distance between the first perimeters, and the length along the surface between the first perimeters and the distance between the first perimeters The auxetic structure plate is out-of-plane deformed so as to absorb the difference. At that time, since at least a part of the region between the first peripheral edges of the auxetic structure plate is also joined to the thin substrate, the thin substrate is also out-of-plane deformed together with the auxetic structure plate. Since the out-of-plane deformation between the auxetic structure plate and the thin substrate is achieved only by contracting the contraction element, the contraction element is contracted at any time so that the out-of-plane deformation of the thin deformation panel occurs at any time. It is possible to carry out transformations. In the above structure, the contraction element may be provided so as to be contracted along the surface of the auxetic structure plate. Therefore, as the contraction element, along the surface of the auxetic structure plate, preferably in-plane. It is possible to adopt a shape that can be arranged on the auxetic structure plate, and thus, a mechanism for applying a force for deforming the auxetic structure plate out of plane (in this case, the extension force of the auxetic structure plate) is Can be arranged along the surface in or near the surface.

Further, in the above configuration of the present invention, in order to generate the out-of-plane deformation of the auxetic structure plate and the thin substrate as described above, the first end of the contraction element bonded to the thin substrate and the auxetic structure plate are joined. The first and/or second peripheral edges of the thin substrate are held in a restrained state as described above. In order to achieve such a state, their joints in the thin substrate are fixed in an arbitrary manner. It may have been done. For example, in one embodiment, the linear region connecting the joint part of the peripheral edge of the auxetic structure plate and the joint part of the contraction element is fixed to a frame member made of a rigid material or is made of the rigid material itself. You may Alternatively, in order to prevent the contraction element joints in the thin substrate or the contraction element joints and the peripheral edge joints of the auxetic structure plate from coming close to each other, the sections are connected by rigid rods. Alternatively, a member such as a belt-like member having a spring constant in the peripheral direction higher than the spring constants of the auxetic structure plate and the thin substrate is bonded to the bonding site on the peripheral edge of the auxetic structure plate. It may have been done. As the band-shaped body, a band-shaped body having a width or a thickness such that the change in the peripheral length becomes small as described above can be adopted. Alternatively, when the laminar panel of the present invention is fixed or fitted as part of the surface of any structure, the first end of the retracting element and the second end of the retracting element are not joined. The length of the side of the auxetic structure plate between the second peripheral edge and the second peripheral edge of the auxetic structural plate is not shortened, and the portions of the thin substrate bonded to the pair of first peripheral edges of the auxetic structural plate are those portions. In order to prevent the displacement amount of the distance between them from exceeding the displacement amount of the length along the surface between the pair of first peripheral edges when the auxetic structure plate is extended, It may be fixed to the surface of the sheet by any method such as adhesion or fastening.

In the embodiment, specifically, the auxetic structure plate includes a pair of opposing first peripheral edges along the first direction and a second Between a pair of second peripheral edges along the direction of, and curved toward the peripheral edges that are symmetrically opposed and connected to both ends of the first peripheral edge, between the midpoint of the first peripheral edge and the center of the auxetic structure plate. It is arbitrarily set along each of at least one intermediate curved line extending through the existing point and a midpoint connecting line connecting the midpoint of the intermediate curved line and the midpoint of the first peripheral edge. The material may exist in a good width, and in other areas, the material may be formed as a thin plate-shaped member having a stolen shape.

Thus, in the thin deformable panel of the present invention, the deforming force applying mechanism for causing out-of-plane deformation can be arranged along the surface in or near the surface of the panel. For example, it can be said that the panel is configured so that it can be deformed out-of-plane autonomously (without the need to apply force from outside the plane). According to such a configuration, it is not necessary to secure a space for providing a deforming force applying mechanism on both sides of the thin deformable panel, other than a wiring structure for controlling the contraction element, etc. It is expected that the thin deformable panel that selectively causes the out-of-plane deformation can be used in a wider range than before, as illustrated in the section (1).

Other objects and advantages of the present invention will be apparent from the following description of the preferred embodiments of the present invention.

1A and 1B are schematic perspective views of one embodiment of the thin deformable panel according to the present embodiment ((A) is an exploded view of components for the purpose of explanation) .). 1C and 1D are constituent elements of the thin deformable panel according to the present embodiment as seen along the lines shown in FIGS. 1C and 1D, respectively. FIG. 3 is a schematic cross-sectional view illustrating a joined state of FIG. FIG. 1E is a diagram schematically showing the configuration of the heating element arranged in the contraction element of the thin deformable panel according to the present embodiment. FIG. 2 is a schematic perspective view of another embodiment of the thin deformable panel according to the present embodiment. 3A and 3B are schematic plan views of the auxetic structure plate of the thin deformable panel according to the present embodiment of FIG. 1A. (A) is before extension and (B) is after extension. FIG. 4A is a calculation simulation image when out-of-plane deformation is generated in the thin deformation panel illustrated in FIGS. 1A and 1B, and FIGS. 5A and 5B are cross-sectional views taken along lines (B) and (C) in FIG. 4A, respectively. FIG. 5 is a diagram illustrating various uses of the thin deformable panel according to the present embodiment. FIG. 6 is a schematic diagram illustrating a conventional deforming force applying mechanism when the panel is out-of-plane deformed.

P... Thin deformed panel 1... Thin substrate 1a, 1b... Edge of thin substrate 2... Authentic structure plate 2a, 2b... Edge of auxetic structure plate 2c... Intermediate curved band of auxetic structure plate 2d... Authentic structure plate Mid-point connection band 3, 4... Contraction element 5... Heating element 3... Thin plate

The present invention will be described in detail below with reference to the accompanying drawings with respect to some preferred embodiments. In the drawings, the same reference numerals indicate the same parts.

Configuration of Thin Deformation Panel With reference to FIGS. 1A and 1B, a thin deformation panel P of the present embodiment has an auxetic structure plate 2 superposed on a thin substrate 1 as shown in the drawings, and will be described below. And the strip-shaped contraction elements 3 and 4 are juxtaposed between the pair of opposed peripheral edges 2a of the auxetic structure plate 2 and the thin substrate 1a, and are joined in the manner described below. It has a different configuration.

In the configuration shown in the figure, the thin substrate 1 has an arbitrary rigidity that can hold a planar structure autonomously, that is, without using an external force, and can bend in an out-of-plane direction. It may be formed of an elastic material such as metal, resin, plastic, composite material, paper, wood and the like.

The auxetic structure plate 2 mounted on the thin substrate 1 may also be formed of any elastic material that can be curved in the out-of-plane direction, for example, metal, resin, plastic, composite material, paper, wood, or the like. .. As shown, the auxetic structure plate 2 is surrounded by a pair of opposed peripheral edges 2a, 2b, of which the peripheral edge 2b (first peripheral edge) is bonded onto the thin substrate 1. In the figure, since the auxetic structure plate 2 and the thin substrate 1 have the same width in the direction (second direction) orthogonal to the peripheral edge 2b, the peripheral edge 2b of the auxetic structure plate 2 is the thin substrate 1 However, the present invention is not limited to this. On the other hand, the peripheral edge 2a (second peripheral edge) of the auxetic structure plate 2 is bonded onto the thin substrate 1 via the belt-shaped contracting elements 3 and 4. In this regard, as illustrated in FIGS. 1A and 1B, the contraction elements 3 and 4 may be bonded to both of the pair of peripheral edges 2a of the auxetic structure plate 2. As illustrated in the above, the contraction elements 3 and 4 may be bonded to only one of the pair of peripheral edges 2 a of the auxetic structure plate 2. In any case, as understood from the drawings, in the direction orthogonal to the peripheral edge 2a (first direction), the auxetic structure plate 2 has at least one peripheral edge 2a with the contracting elements 3 and 4 interposed therebetween. Since it is bonded onto the thin substrate 1, its size is shorter than that of the thin substrate 1.

The auxetic structure plate 2 has an auxetic structure that extends in the second direction when extended in the first direction, as described in the section "Outline of the Invention". In this embodiment, the auxetic structure plate 2 may be as follows, for example. Referring to FIG. 1(A), (B) or FIG. 3(A), first, in the auxetic structure plate 2, a certain degree of width (in the plane direction) is provided at the periphery thereof. There are defined two pairs of opposite peripheral edges 2a, 2b. Then, inside each of the pair of peripheral edges 2b, connected to both ends of the peripheral edge 2b and curved symmetrically inward, a point between the midpoint of the peripheral edge 2b and the center of the auxetic structure plate 2 is set. At least one intermediate curved band 2c having a certain width (in the surface direction) is defined along the intermediate curved line that curves so as to pass therethrough (in the example shown, inside each of the peripheral edges 2b). 2 lines are defined), and a midpoint connection having a certain width (in the plane direction) along a midpoint connection line that connects the midpoint of the intermediate curved band 2c and the midpoint of the peripheral edge 2b. Bands 2d are defined inside each of the peripheral edges 2b. Thus, the auxetic structure plate 2 is formed in a state where the material is present in the peripheral edges 2a, 2b, the intermediate curved band 2c, and the midpoint connecting band 2d defined as described above, and the other regions are hollowed out. In this case, as will be described later, when the structure is extended by pulling the peripheral edge 2a outward in a direction perpendicular to the extending direction, the structure also extends in the extending direction of the peripheral edge 2a.

The contraction elements 3 and 4 arranged and joined between the peripheral edge of the auxetic structure plate 2 and the thin substrate 1 are formed in a strip shape or a strap shape extending in the plane of the auxetic structure plate 2 and the thin substrate 1. Can be any selectively retractable element described. As the contraction elements 3 and 4, specifically, for example, an element made of a shape memory alloy that contracts when a predetermined temperature is reached, an element made of a piezoelectric material that expands and contracts by adjusting an applied voltage, or the like is advantageously used. To be In the case of these contraction elements, it is necessary to provide a heating heater for temperature control for expansion and contraction of the element and an electrode for applying a voltage to the element, but the parts used for that purpose are an electric cable, an electric resistance Parts such as wires and electrode plates that require almost no space outside the planes of the auxetic structure plate 2 and the thin substrate 1 and that are necessary for the operation of the thin deformable panel P are in or near the plane. It can be accommodated along the surface (the temperature control device and the voltage control device of the contraction element are connected to the thin deformed panel P via an electric cable, but these control devices are included in the thin deformed panel P. Since it is not necessary to arrange the thin deformation panel P in a region close to the main body, and thus it is not necessary to use a component that requires a large space in the vicinity of the surface of the thin deformation panel P, the thin deformation panel P is installed in a thin type. It is sufficient if the deformation panel P has a space in which it can be deformed out-of-plane.

Thus, in the configuration of the thin deformable panel P described above, as described above, the auxetic structure plate 2 is placed on the thin substrate 1, and the pair of opposing peripheral edges 2b are first formed into the edges of the thin substrate 1. 1b, and at least a part of the intermediate curved band 2c and the midpoint connecting band 2d (for example, FIG. 1B) so that the thin substrate 1 undergoes out-of-plane deformation as described later. The dotted line region along the middle curved band 2c), preferably the entire region, may be bonded to the surface of the thin substrate 1 (see FIG. 1C. In the figure, S indicates a bonding site. .). On the other hand, regarding the pair of opposing peripheral edges 2a of the auxetic structure plate 2, when the contracting elements 3 and 4 are arranged on both sides of the auxetic structure plate 2 as shown in FIG. Both of them may be bonded to the ends 3a and 4a of the contracting elements 3 and 4, and the ends 3b and 4b of the contracting elements 3 and 4 may be bonded to, for example, the edge 1a of the thin substrate 1 (see FIG. 1( See D). In the figure, S represents the joining site.). Further, as shown in FIG. 2, when the contracting elements 3 and 4 are arranged on one side of the auxetic structure plate 2, the structure on the side where the contracting elements 3 and 4 are arranged may be the same as the above. On the side where the contraction elements 3 and 4 are not arranged, the peripheral edge 2a of the auxetic structure plate 2 may be directly bonded to the edge 1a of the thin substrate 1, for example. When the contraction elements 3 and 4 are elements made of a shape memory alloy, for example, as shown in FIG. 1(E), the heating element 5 (electric resistance wire) is arranged on the contraction elements 3 and 4. This makes it possible to heat the contraction elements 3, 4.

By the way, as described in the "Outline of the Invention", in the configuration of the thin deformable panel P described above, in order to cause the out-of-plane deformation of the auxetic structure plate 2 and the thin substrate 1, the contraction element 3 is required. 4, the auxetic structure plate 2 is surely extended in the direction in which the pair of peripheral edges 2a are separated from each other, and the distance between the pair of peripheral edges 2b is between the peripheral edges 2b. It must be shorter than the length along the surface of the substrate 1. Therefore, such a condition is satisfied, that is, the distance between the ends 3b and 4b of the contraction elements 3 and 4 is not shortened when the contraction element is contracted, and the distance between the peripheral edges 2b of the auxetic structure plate 2 is small. The periphery of the thin deformable panel P is restrained in an arbitrary manner so that the distance does not increase excessively. Specifically, as shown in FIG. 1A, in the configuration in which the contracting elements 3 and 4 are arranged on both sides of the peripheral edge 2a of the auxetic structure plate 2, the end portions 3b of the contracting elements 3 and 4 on both sides are arranged. , 4b may be held in any manner such that the distance between them does not substantially shorten ("not substantially shortening" means that the end portion 3b exceeds the contraction amount of the contraction elements 3, 4). It means that the distance between 4b is not shortened.). For example, a rod member or a frame member made of a rigid material is arranged between the ends 3b, 4b of the contracting elements 3, 4 on both sides so that the distance between the ends 3b, 4b is maintained. Good. Similarly, as shown in FIG. 2, in the configuration in which the contracting elements 3 and 4 are arranged on one side of the auxetic structure plate 2, the thin ends 3b and 4b of the contracting elements 3 and 4 on one side are thin. A rod member or a frame member made of a rigid material is arranged between the joining portion to the substrate and the joining portion of the peripheral edge 2a on the other side to the thin substrate so that the distance between the joining portions is maintained. Good. Regarding restraint between the peripheral edges 2b of the auxetic structure plate 2, a rod member or a frame member made of a rigid material is arranged between the peripheral edges 2b so that the increase in the distance between the peripheral edges 2b is restricted. Good. Alternatively, the linear region connecting the joint portion of the peripheral edge 2b (or 2a) of the auxetic structure plate 2 and the joint portions 3b and 4b of the contraction element is fixed to a frame member made of a rigid material, or the rigid material itself. It may be formed. In still another aspect, a member such as a belt-like body having a spring constant in the peripheral direction with respect to the joining portion at the peripheral edge of the auxetic structure plate 2 is higher than the spring constants of the auxetic structure plate 2 and the thin substrate 1. (Not shown) may be joined or the like. As the band-shaped body, one formed in a shape of width or thickness such that the change in peripheral length becomes small as described above may be adopted. Alternatively, when the thin deformed panel P is fixed or fitted as a part of the surface of an arbitrary structure, each part of the thin substrate is arranged relative to the surface of the structure so as to satisfy the above requirements. Then, they may be fixed in any form such as adhesion and fastening.

Regarding the contraction elements 3 and 4, the set of contraction elements 3 and the set of contraction elements 4 may be contracted at the same time or may be contracted separately. As will be described in detail later, the thin deformable panel P of the present embodiment causes out-of-plane deformation each time the contracting element contracts. Therefore, when the contracting element repeatedly expands and contracts, the out-of-plane deformation repeats. It is expected that the planar state and the out-of-plane deformed state will appear alternately, and when there is an upper limit to the expansion/contraction cycle in one contraction element, the set of contraction elements 3 and the contraction element 4 It is possible to double the upper limit cycle of repeated out-of-plane deformation by alternately expanding and contracting with the group of.

Operation of Thin Deformation Panel Referring to FIGS. 3(A) and 3(B), in the auxetic structure plate 2, the contraction elements 3 and 4 contract, so that a pair of peripheral edges 2 a of the auxetic structure plate 2 Then, when the force F acts in the direction in which they are separated from each other, the peripheral edges 2a are respectively displaced in the direction of the arrow α, and the auxetic structure plate 2 is extended. Then, the plurality of intermediate curved strips 2c extending inside the peripheral edge 2b are respectively expanded and outwardly expanded in the direction of arrow β, which is substantially perpendicular to the direction of arrow α. Since the displacement occurs, and the displacement is further transmitted to the peripheral edge 2b by the midpoint connecting band 2d and the peripheral edge 2b is deformed, the auxetic structure plate 2 moves in the direction perpendicular to the contracting direction of the contracting element. Will also be extended. Then, the thin substrate 1 laminated on the auxetic structure plate 2 is further contracted when the contraction elements 3 and 4 are arranged on the peripheral edge 2b of the auxetic structure plate 2 (or on only one side of the peripheral edge 2a). The thin substrate 1 is joined together with the auxetic structure plate 2 in all directions, because the thin substrate 1 is joined together with the peripheral edge 2a) on which the elements 3 and 4 are not arranged and at least a part between the pair of peripheral edges 2b. It will be extended.

As described above, when the auxetic structure plate 2 and the thin substrate 1 extend due to the contraction of the contraction element, as described above, for example, the relative positional relationship between the pair of opposed peripheral edges 2b substantially changes. Since the distance between the peripheral edges 2b is restrained so as not to be longer than the length between the peripheral edges 2b along the extended surface of the auxetic structure plate 2 and the thin substrate 1, the distance between the peripheral edges 2b is restrained. As illustrated in FIG. 4, the auxetic structure plate 2 and the thin substrate 1 are curved so as to project out of the plane so that the distance between the peripheral edges 2b and the surfaces of the auxetic structure plate 2 and the thin substrate 1 are aligned. The extension is performed while absorbing the difference from the length between the peripheral edges 2b.

Calculation Experimental Example The degree of out-of-plane deformation occurring in the specifically designed configuration of the thin deformable panel of the present embodiment described above was verified by calculation simulation.

In the configuration of the thin deformed panel, a steel plate (longitudinal elastic modulus of 200 GPa) having dimensions of 200 mm (edge 1a)×320 mm (edge 1b)×0.1 mm (thickness) was set as the thin substrate. For the auxetic structure plate, a titanium steel plate (longitudinal elastic modulus 114 GPa) having dimensions of 198 mm (peripheral 2a)×240 mm (peripheral 2b)×0.3 mm (thickness) was set. As the contraction element, a strip element (elastic modulus is 114 GPa) made of Ni-Ti-based shape memory alloy having a width of 18 mm, a length of 40 mm and a thickness of 0.5 mm was set. The shape memory alloy of the contraction element is subjected to shape memory treatment so that contraction of 5% occurs at 80° C., and the contraction stress is assumed to occur at 500 Mpa in normal use and 800 Mpa at maximum, (return to the state before contraction). The original shape recovery stress was assumed to be -150 MPa. The contracting element is heated to 80° C. once to develop a memory shape (contraction of 5%), and then tension is applied so as to give an elongation strain of 6-8% along the same direction as the contracting direction. Then, the length was adjusted to 40 mm with the tension removed. As shown in FIGS. 1(A) and 1(B), the contraction elements are arranged on the peripheral edges of both sides of the auxetic structure plate, and as described above, the auxetic structure plate and the contraction element are mounted on the thin substrate. It should be joined to each other. The heating of the contraction element was performed by a heating element attached to the contraction element as illustrated in FIG. 1(E).

4A to 4C are out-of-plane deformations obtained by calculation simulation by FEM analysis under the condition that all contracting elements were heated at 80° C. in the configuration of the above design conditions. The state of the thin deformation|transformation panel which produced is shown. When the displacement of the thin plate member was estimated, the displacement of the convexly projecting surface from the position of the surface before deformation was about 76 mm at the center of the substrate. Thus, it has been shown that the configuration of the present embodiment described above can realize a thin deformable panel that can be selectively deformed out of plane.

By the way, when a shape memory alloy element is used as the contraction element as described above, even if the heating is stopped after the contraction element contracts due to heating, the contraction element remains in the contracted state unless tension is applied. Becomes In this regard, in the thin deformable panel having the above-mentioned configuration, the thin substrate and the auxetic structure plate are made of steel plate, and the out-of-plane deformation caused by the contraction of the contraction element is elastic deformation. After the heating of the device is stopped, the elastic force of the thin substrate and the auxetic structure plate acts in the direction of contracting to return the thin substrate and the auxetic structure plate to the original flat plate shape. As a result, the contraction element is extended. Therefore, when the heating and the stopping of the heating of the contraction element are repeated, the out-of-plane deformation of the thin deformation panel and the return to the flat plate state are repeated. In addition, the stress required to return the contracted element in the state where the memory shape is expressed, that is, the contracted element in the contracted state to the state before the contraction (the original shape restoring stress) is 15 to 15 times the normal contraction stress generated when the contracted element contracts. Since it is about 20%, the thickness and dimensions of the thin substrate and the auxetic structure plate are preferably set so that the elastic force generated by the out-of-plane deformation of the thin substrate and the auxetic structure plate can cover the original shape restoring stress. May be done.

The thin deformable panel that can be deformed out of plane according to the present embodiment can be used for various purposes. For example, as shown in FIG. 5(A), the thin deformable panel P has a body surface (P) for the purpose of changing the aerodynamic characteristics, absorbing impact force, changing the design, etc. in the vehicle body. Can be used as an out-of-plane deformation element or as an element of an interior member such as a dashboard in a vehicle. In addition, as illustrated in FIG. 5B, the thin deformable panel P is used in a structure such as a solar panel, a sign, or a signboard where a board SLB is attached to an upright column, and is followed by sunlight and antiglare. , And can be used as a driving element for changing the direction of the board SLB (deformed from P to Pm) for the purpose of visual enhancement. Further, as shown in FIG. 5(C), the thin deformable panel P is a control surface member such as an aircraft wing skin intended for weight reduction and flight performance improvement, and a flap that does not require a drive device. It can be used as an out-of-plane deformation element. Further, as shown in FIG. 5(D), a plurality of thin deformation panels are arrayed in a luggage transport or self-propelled robot drive device to appropriately generate out-of-plane deformation, thereby It is also possible to express a wave motion for transferring R and the like. It should be understood that, in the use of the thin deformable panel as described above, the mechanism for applying the deforming force for deforming the panel out-of-plane is arranged along the surface in or near the surface. That is, the space to be secured outside the plane is significantly reduced.

Although the above description is made in connection with the embodiments of the present invention, many modifications and changes can be easily made by those skilled in the art, and the present invention is limited to the embodiments illustrated above. It will be apparent that the present invention is not limited but applies to various devices without departing from the concept of the invention.

Claims (1)

A thin deformable panel,
A thin substrate that can be deformed out of plane,
At least one contraction element, the first end is bonded on the thin substrate, the contraction element for selectively contracting between the first end and the second end,
An out-of-plane deformable auxetic structure plate is provided in a plane intersecting the first direction with a pair of first peripheral edges extending along the first direction in the plane and facing each other. Is surrounded by a pair of second peripheral edges that extend along the second direction and face each other, and have an auxetic structure that extends in the second direction when extended in the first direction, At least one of the pair of second peripheral edges is bonded to the second end of the contraction element, and at least a part of the area between the peripheral edge not bonded to the contraction element and the pair of first peripheral edges. Includes an auxetic structure plate bonded to the thin substrate,
Even if the contracting element contracts, the length from the first end of the contracting element to the second peripheral edge of the auxetic structure plate where the second end of the contracting element is not joined does not become short. As described above, the position of the first end of the contraction element is constrained, and the displacement amount of the distance between the pair of first peripheral edges of the auxetic structure plate is equal to that of the first pair of first ends when the auxetic structure plate is extended. When the contraction element contracts in a state where the distance between the pair of first peripheral edges is constrained so as not to exceed the displacement amount of the length along the surface between the peripheral edges, the auxetic structure plate and the thin substrate A thin deformed panel in which and are integrally deformed out of plane.