JP7020439B2 - Thin deformable panel that deforms out of plane using an auxetic structure - Google Patents

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, an out-of-plane deformation is actively performed by using a thin plate having an auxetic structure. It relates to a possible thin panel.

In general, the Poisson's ratio of a solid material is positive, so when a member made of a solid material is stretched in one direction, it contracts in a direction perpendicular to that direction. However, there is also a structure called "auxetic structure" in which the Poisson's ratio is negative, that is, a special structure in which when a member is stretched or stretched in one direction, it is stretched or stretched even in a direction perpendicular to that direction. Various techniques that are formable and related to such "auxetic structures" have been proposed. For example, Patent Document 1 proposes a method for producing a composite material that achieves a state of exhibiting a negative Poisson's ratio by arranging two types of linear elements having different elastic modulis in a crossed manner in the composite material. There is. Further, in Patent Document 2, a member having an orthotic structure is adopted in the footwear, and an impact is absorbed by utilizing the peculiar strain characteristic due to the orthotic structure in response to an input such as a load applied from the outside. The configuration to do is proposed. Further, 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 sound energy.

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

By the way, when trying to give various deformation functions to a planar structure or a panel-like member (hereinafter, referred to as "panel"), in general, a mechanism for applying a force for such deformation is separately added. It will be. For example, when the panel is deformed out of the plane, as shown in FIG. 6, a mechanism (deformation force applying mechanism) Z that applies a force for deformation of a cylinder, a motor, or the like to the panel is provided on the panel. A configuration such as an exterior exterior will be taken. In such a case, as is clear from the figure, a space D for the deformation force application mechanism is required, and as a result, a place where such an out-of-plane deformable panel can be used (of machinery and equipment). (Part of the structure, etc.) will be restricted. Therefore, if various deformation functions, particularly out-of-plane deformation functions, are to be imparted to the panel, the deformation force applying mechanism is not exteriorized outside the surface of the panel, and is in or near the surface of the panel along the surface. If the panels can be placed and, so to speak, can be autonomously deformed out of the plane, the available locations of such out-of-plane deformable panels will increase, and any machinery or structure will be available. It is expected that various structures or configurations that have not been seen before can be achieved.

With respect to the configuration of the out-of-plane deformable panel as described above, the inventor of the present invention can utilize the special deformation characteristics of the auxetic structure as described in the column of "conventional technology" for out-of-plane deformation. It has been found that a configuration in which the deformation force applying mechanism of the above is arranged along the surface in or near the surface of the panel is feasible. This finding is utilized in the present invention.

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

According to the present invention, the above-mentioned problem is a thin deformable panel.
A thin substrate that can be deformed out of the plane,
A shrinking element having at least one shrinking element, the first end of which is joined onto the thin substrate and selectively shrinking between the first and second ends.
An out-of-plane deformable auxetic structural plate in the plane that extends along the first direction in the plane and intersects the pair of first edges facing each other in the first direction. It has an auxetic structure that extends along the second direction and is surrounded by a pair of second edges facing each other and extends in the second direction when extended in the first direction. At least one of the pair of second rims is joined to the second end of the shrink element, with at least a portion of the area between the rim not joined to the shrink element and the pair of first rims. Includes an auxetic structural plate bonded to the thin substrate.
Even if the contraction element contracts, the length from the first end of the contraction element to the second peripheral edge of the autetic structure plate to which the second end of the contraction element is not joined is not shortened. As described above, the position of the first end of the contractile element is constrained, and the amount of displacement of the distance between the pair of first peripheral edges of the organic structural plate is the pair of first when the organic structural plate is extended. When the contractile element contracts while 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 are used. Is achieved by a thin deformable panel that integrally deforms out of the plane.

In the above, "out-of-plane deformation" means that the inner region of a thin plate-like member, that is, a thin substrate and an auxetic structural plate, is in a direction perpendicular to the surface direction relative to its peripheral edge. It shall refer to a deformation that protrudes and displaces. A "thin substrate" is any elastic material (metal, resin, plastic, composite material) that is rigid enough to hold a planar structure autonomously (ie, without the use of external forces) and is bendable in the out-of-plane direction. , Paper, wood, etc.). A "shrink element" is an element formed of any element that can be selectively shrunk, for example, a shape memory alloy or a piezoelectric material, and is formed in a band shape or a strap shape that can be arranged along the surface of a thin substrate. Members are available. As described above, the contractile element has a first end bonded onto the thin substrate and extends along the thin substrate, and a second end bonded to the peripheral edge of the auxetic structural plate. The "ausetic structure plate" is a plate-shaped member having the deformation characteristics of the auxetic structure as described above, and is an arbitrary elastic material (metal, resin, plastic, composite material, paper, which can be bent in the out-of-plane direction). It may be formed of wood or the like (preferably, it may have rigidity capable of autonomously holding a planar structure, but it is not limited to this), and as described above, the shrinking element is joined. At least a portion of the area between the unsheathed edges and the pair of opposing first edges is joined to the thin substrate. In this regard, the shrink element may be joined to both of the pair of second perimeters of the autetic structure plate, in which case the contraction element is first from each of the second perimeters of the autetic structure plate. Extending outward along the direction, each first end of the contractile element will be joined to the thin substrate and a pair of opposing first edges of the auxetic structural plate will be joined to the thin substrate. .. Further, the contractile element may be configured to be joined only to one of the pair of second peripheral edges of the autetic structural plate, in which case the contractile element may be joined to the pair of opposite first peripheral edges of the autetic structural plate. The second peripheral edge of the autetic structure plate to which the shrink element is not bonded is bonded to the thin substrate. Then, in the above configuration, the length from the first end of the shrinking element to the second peripheral edge of the autetic structural plate to which the second end of the shrinking element is not joined is not shortened. If it is held, when the contraction element contracts, the auxetic structure plate is always extended in parallel with the contraction direction of the contraction element. The length from one end to the second peripheral edge of the auxetic structure plate to which the second end of the contraction element is not joined is not shortened, that is, the auxetic structure plate is retracted when the contraction element is contracted. If the contractile elements are joined to both sides of a pair of second edges of the auxetic structural plate to ensure extension, the spacing between the first ends of the contractile elements on both sides is constrained. Or, if the shrink element is joined to only one of a pair of second perimeters of the axetic structural plate, the first end of the shrink element and the autetic (the one to which the shrink element is not joined). The position of the first end of the shrink 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 abstoxic structural plates on the thin substrate is constrained. The site where one perimeter is joined (becomes a linear region) is such that the distance between such sites is along the surface between the pair of first perimeters of the orthotic structure plate during extension. It is constrained to remain shorter than its length.

According to the above configuration, since the joint portion of the shrink 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 is formed. When the contractile element contracts on both sides or one side of the second peripheral edge of the plate, the autetic structural plate is first stretched along the first direction. Then, due to the characteristics of the auxetic structure plate, it extends along the second direction, but the first peripheral edge of the auxetic structure plate is constrained so as to limit the displacement as described above. The length along the plane between the first rims of the structural plate is longer than the distance between the first rims, and the length along the plane between the first rims and the distance between the first rims In order to absorb the difference between the above, the auxetic structure plate will be deformed out of the plane. 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 shrinking the shrink element, the out-of-plane deformation of the thin deformation panel can be achieved at any time by shrinking the shrink element at any time. It is possible to perform transformations. In the above configuration, the shrinking element may be provided so as to be able to shrink along the surface of the auxetic structure plate, and therefore, as a shrinking element, it is preferably in-plane along the surface of the auxetic structure plate. It is possible to adopt a shape that can be arranged in the above, and thus the mechanism for applying the force for out-of-plane deformation of the orthotics structure plate (in this case, the extension force of the orthotics structure plate) is the orthotics structure plate. It can be arranged along the plane in the plane or in the vicinity of the plane.

Further, in the above-mentioned 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 shrinkage element bonded to the thin substrate and the auxetic structure plate are formed. The first and / or second peripheral edges of the above are constrained as described above, and their joints in the thin substrate are fixed in any manner so that such a state can be achieved. It may have been done. For example, in one embodiment, the linear region connecting the joint portion of the peripheral edge of the auxetic structural plate and the joint portion of the contractile element is fixed to a frame member made of a rigid body material or formed of the rigid body material itself. It's okay. Alternatively, the joint parts of the shrink element in the thin substrate or the joint part of the shrink element and the joint part of the peripheral edge of the autetic structure plate are connected by a rigid rod material so as not to be close to each other. Alternatively, a member such as a strip whose spring constant in the peripheral direction is higher than the spring constant of the auxetic structural plate and the thin substrate is joined to the joint portion of the peripheral edge of the auxetic structural plate. It may have been done. As the strip-shaped body, one formed in a shape having a width or a thickness such that the change in peripheral length becomes small as described above can be adopted. Alternatively, when the thin plate panel of the present invention is fixed or fitted as part of the surface of any structure, the first end of the shrink element and the second end of the shrink element are not joined. The parts in the thin substrate joined to the pair of first rims of the auxetic structure plate so that the length between them and the second rim of the side auxetic structure plate are not shortened are those parts. Each part of the thin substrate is a structure so that the displacement amount of the distance between them does not exceed the displacement amount of the length along the surface between the pair of first peripheral edges when the autetic structure plate is extended. It may be fixed to the surface of the above surface in any manner such as adhesion and fastening.

In embodiments, as will be described in the section of later embodiments, specifically, the auxetic structural plate will have a pair of opposing first edges along a first direction and a second. Between a pair of second rims along the direction of, and the midpoint of the first rim and the center of the autetic structure plate, which is connected to both ends of the first rim and curves symmetrically toward the opposite rim. Arbitrarily set along each of at least one intermediate curve line extending past an existing point and a midpoint connecting line connecting the midpoint of the intermediate curve line and the midpoint of the first peripheral edge. The material may be present in a good width and may be formed in other regions as a sheet-like member in the shape of a stealing material.

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

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

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

P ... Thin deformable panel 1 ... Thin substrate 1a, 1b ... Edge of thin substrate 2 ... Orthotic structural plate 2a, 2b ... Peripheral of the orthotic structural plate 2c ... Intermediate curved band of the orthotic structural plate 2d ... Midpoint connecting band 3, 4 ... Shrinking element 5 ... Heating element 3 ... Thin plate

Some preferred embodiments of the present invention will be described in detail below with reference to the accompanying figures. In the figure, the same reference numerals indicate the same parts.

Configuration of the Thin Deformable Panel With reference to FIGS. 1 (A) and 1 (B), the thin deformable panel P of the present embodiment has an auxetic structural plate 2 superimposed on the thin substrate 1 as shown in the drawing, and will be described below. The strip-shaped shrinkage elements 3 and 4 are juxtaposed between the pair of opposing peripheral edges 2a of the auxetic structure plate 2 and the thin substrate 1a, and are joined in the manner described below. Has a structure.

In the illustrated configuration, the thin substrate 1 has any rigidity that can hold the planar structure autonomously, that is, without using an external force, and can be curved in the out-of-plane direction. It may be made of an elastic material such as metal, resin, plastic, composite material, paper, wood or the like.

The auxetic structural plate 2 placed on the thin substrate 1 may also be formed of any elastic material that can be bent in the out-of-plane direction, for example, metal, resin, plastic, composite material, paper, wood, or the like. .. As shown in the figure, the auxetic structure plate 2 is surrounded by two pairs of opposite peripheral edges 2a and 2b, of which the peripheral edge 2b (first peripheral edge) is joined onto the thin substrate 1. In addition, in the figure, since the width of the auxetic structure plate 2 and the thin substrate 1 in the direction orthogonal to the peripheral edge 2b (second direction) is the same, the peripheral edge 2b of the auxetic structural plate 2 is the thin substrate 1. It may be joined to the adjacent edges 1b of, but is not limited to this. On the other hand, the peripheral edge 2a (second peripheral edge) of the auxetic structure plate 2 is joined onto the thin substrate 1 via the band-shaped shrinkage elements 3 and 4. In this regard, as illustrated in FIGS. 1 (A) and 1 (B), the shrinkage elements 3 and 4 may be bonded to both of the pair of peripheral edges 2a of the auxetic structure plate 2, and FIG. 2 shows. As illustrated above, the shrinkage elements 3 and 4 may be bonded to only one of the pair of peripheral edges 2a of the auxetic structure plate 2. In either case, as can be understood from the figure, in the direction orthogonal to the peripheral edge 2a (first direction), in the auxetic structural plate 2, at least one peripheral edge 2a is interposed via the shrinkage elements 3 and 4. Since it is joined on the thin substrate 1, its size is shorter than that of the thin substrate 1.

As described in the column of "Overview of the invention", the auxetic structure plate 2 has an auxetic structure that extends in the first direction and also in the second direction. In the present embodiment, the auxetic structural plate 2 may be, for example, as follows. With reference to FIGS. 1 (A), (B) or 3 (A), first, the auxetic structural plate 2 is to have a certain width (in the plane direction) around it. Two sets of opposing peripheral edges 2a and 2b are defined in. Then, on the inside of each of the pair of peripheral edges 2b, the points connected to both ends of the peripheral edges 2b, curved inward symmetrically, and between the midpoint of the peripheral edges 2b and the center of the auxetic structural plate 2 are formed. At least one intermediate curved zone 2c having a certain width (in the plane direction) is defined along the intermediate curved line arced to pass through (in the illustrated example, inside each of the peripheral edges 2b). Two rows are defined), and a midpoint connection having a certain width (in the plane direction) along the midpoint connecting line connecting the midpoint of the intermediate curved zone 2c and the midpoint of the peripheral edge 2b. The band 2d is defined inside each of the peripheral edges 2b. Thus, the auxetic structural plate 2 was formed in a state where the material was present in the peripheral edges 2a and 2b defined as described above, the intermediate curved zone 2c, and the midpoint connecting zone 2d, and the other regions were hollowed out. In this case, as will be described later, when the peripheral edge 2a is pulled outwards perpendicular to the extending direction thereof to extend the structure, the structure also extends in the extending direction of the peripheral edge 2a.

The shrinkage 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 band shape or a strap shape extending in the plane of the auxetic structure plate 2 and the thin substrate 1. It may be any element that is selectively contractible. As the contractile elements 3 and 4, specifically, for example, an element made of a shape memory alloy that shrinks when a predetermined temperature is reached, an element made of a piezoelectric material that expands and contracts by adjusting an applied voltage, and the like are advantageously used. Be done. In the case of these contractile 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 and an electric resistance. Wires, electrode plates, etc. that require almost no space outside the plane of the auxetic structure plate 2 and the thin substrate 1, and the parts necessary for operating 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 contractile element are connected to the thin deformation panel P via an electric cable, and these control devices are connected to the thin deformation panel P. Since it is not necessary to arrange the thin deformable panel P in a region close to the main body, and therefore it is not necessary to use a part that requires a large space near the surface of the thin deformable panel P, the thin deformable panel P is installed in a thin shape. It is sufficient if the deformable panel P has a space that can be deformed out of the plane.)

Thus, in the configuration of the thin deformable panel P described above, as already described, the auxetic structural plate 2 is placed on the thin substrate 1, and the pair of opposing peripheral edges 2b first form the edge of the thin substrate 1. It is joined to 1b, and as will be described later, at least a part of the intermediate curved band 2c and the midpoint connecting band 2d (for example, FIG. 1B) so that out-of-plane deformation occurs in the thin substrate 1. (Dotted region along the middle curved band 2c), preferably the entire area may be joined to the surface of the thin substrate 1 (see FIG. 1 (C), where S indicates the joining site). There.). On the other hand, regarding the pair of facing peripheral edges 2a of the auxetic structural plate 2, when the shrinkage elements 3 and 4 are arranged on both sides of the auxetic structural plate 2 as shown in FIG. 1A, the pair of peripheral edges 2a Both may be joined to the ends 3a and 4a of the shrinking elements 3 and 4, and the ends 3b and 4b of the shrinking elements 3 and 4 may be joined to, for example, the edge 1a of the thin substrate 1 (FIG. 1 (FIG. 1). See D). In the figure, S indicates the joint site). Further, when the shrinkage elements 3 and 4 are arranged on one side of the auxetic structure plate 2 as shown in FIG. 2, the configuration of the side on which the shrinkage elements 3 and 4 are arranged may be the same as described above. On the non-arranged side of the shrinking elements 3 and 4, the peripheral edge 2a of the auxetic structural plate 2 may be directly bonded to the thin substrate 1, for example, the edge 1a. When the shrinkage elements 3 and 4 are elements made of a shape memory alloy, for example, as illustrated in FIG. 1 (E), the heating element 5 (electrical resistance wire) is arranged on the shrinkage elements 3 and 4. This makes it possible to heat the shrinkage elements 3 and 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 for the auxetic structure plate 2 and the thin substrate 1 to undergo out-of-plane deformation, the shrinkage element 3 is used. The auxetic structure plate 2 is surely extended in the direction in which the pair of peripheral edges 2a are separated from each other at the time of contraction of 4, and the distance between the pair of peripheral edges 2b is between the peripheral edges 2b. It needs to be shorter than the length along the surface of the substrate 1. Therefore, so that such a condition is satisfied, that is, the distance between the end portions 3b and 4b of the contractile elements 3 and 4 is not shortened when the contractile element is contracted, and the distance between the peripheral edges 2b of the auxetic structural plate 2 is not shortened. The perimeter of the thin deformable panel P is constrained in any manner so that the distance does not increase excessively. Specifically, as shown in FIG. 1A, in the configuration in which the shrinkage 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 shrinkage elements 3 and 4 on both sides are arranged. The distance of 4b may be held by an arbitrary method so as not to be substantially shortened (“not substantially shortened” means that the end portion 3b is equal to or greater than the contraction amount of the contraction elements 3 and 4. It means that the distance between 4b is not shortened.) For example, a rod or frame member made of a rigid body material is arranged between the ends 3b and 4b of the contractile elements 3 and 4 on both sides so that the distance between the ends 3b and 4b is maintained. good. Similarly, as shown in FIG. 2, in the configuration in which the shrinkage elements 3 and 4 are arranged on one side of the auxetic structure plate 2, the end portions 3b and 4b of the shrinkage elements 3 and 4 on one side are thin. A rod or frame member made of a rigid body material is arranged between the joint portion to the substrate and the joint portion to the thin substrate on the other side peripheral edge 2a so that the distance between the joint portions is maintained. good. Regarding the restraint between the peripheral edges 2b of the auxetic structure plate 2, a rod member or a frame member made of a rigid body material is arranged between the peripheral edges 2b to limit the increase in the distance between the peripheral edges 2b. good. Alternatively, the linear region connecting the joint portion of the peripheral edge 2b (or 2a) of the auxetic structural plate 2 and the joint portion of the end portions 3b and 4b of the contractile element is fixed to a frame member made of a rigid body material, or the rigid body material itself. It may be formed. In still another aspect, a member such as a strip having a spring constant in the peripheral direction of the joint portion of the peripheral edge of the auxetic structural plate 2 higher than the spring constant of the auxetic structural plate 2 and the thin substrate 1. (Not shown) may be joined or the like. As the strip-shaped body, one formed in a shape having a width or a thickness such that the change in peripheral length becomes small as described above may be adopted. Alternatively, if the thin deformable panel P is fixed or fitted as part of the surface of any structure, each part of the thin substrate will be relative to the surface of the structure to meet the above requirements. It may be fixed in any manner such as adhesion and fastening.

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

Operation of the thin deformable panel With reference to FIGS. 3 (A) and 3 (B), in the orthotics structure plate 2, the shrinkage elements 3 and 4 are contracted with respect to the pair of peripheral edges 2a of the orthotics structure plate 2. When the force F acts in the direction in which they are separated from each other, the peripheral edges 2a are displaced in the direction of the arrow α, respectively, and the auxetic structural plate 2 is extended. Then, the plurality of intermediate curved zones 2c extending inside the peripheral edge 2b are each extended, and at the same time, while increasing the distance outward from each other in the direction of the arrow β substantially perpendicular to the direction of the arrow α. The displacement is further transmitted to the peripheral edge 2b by the midpoint connecting band 2d, and the peripheral edge 2b is deformed. Therefore, the auxetic structure plate 2 is oriented in the direction perpendicular to the contraction direction of the contraction element. Will also be extended. The thin substrate 1 laminated on the auxetic structure plate 2 is further contracted when the shrinkage elements 3 and 4 are arranged on only one of the peripheral edges 2b (or the peripheral edge 2a) of the auxetic structure plate 2. Since the peripheral edges 2a) on which the elements 3 and 4 are not arranged and at least a part of the peripheral edges 2b are bonded to each other, the thin substrate 1 is also joined in all directions together with the auxetic structural plate 2. It will be extended.

As described above, when the auxetic structure plate 2 and the thin substrate 1 extend with the contraction of the contraction element, for example, the relative positional relationship between the pair of facing peripheral edges 2b changes substantially as described above. 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 constrained so as not to be longer. 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 as to extend the distance between the peripheral edges 2b and along the surfaces of the auxetic structure plate 2 and the thin substrate 1. It extends while absorbing the difference from the length between the peripheral edges 2b.

Calculation experiment example The degree of out-of-plane deformation that occurs in the specifically designed configuration of the thin deformation panel of the above embodiment was verified by calculation simulation.

In the configuration of the thin deformable panel, a steel plate (longitudinal elastic modulus 200 GPa) having dimensions of 200 mm (edge 1a) × 320 mm (edge 1b) × 0.1 mm (thickness) was set for the thin substrate. A titanium steel plate (longitudinal elastic modulus 114 GPa) having dimensions of 198 mm (periphery 2a) × 240 mm (periphery 2b) × 0.3 mm (thickness) was set as the auxetic structural plate. As the shrinking element, a strip-shaped element (elastic modulus of 114 GPa) made of a Ni—Ti 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 shrink element is subjected to shape memory processing so that 5% shrinkage occurs at 80 ° C., and shrinkage stress is assumed to be generated at 500 Mpa in normal use and 800 Mpa at maximum (return to the state before shrinkage). It was assumed that the stress for returning to the original shape was -150 MPa. The contractile element is once heated to 80 ° C. to develop a memory shape (5% contraction), and then tension is applied so as to give 6-8% elongation strain along the same direction as the contraction direction. After that, the length was adjusted to 40 mm with the tension removed. As shown in FIGS. 1 (A) and 1 (B), the shrinkage element is arranged on the peripheral edges of both sides of the orthic structure plate, and as described above, the orthodox structure plate and the shrinkage element are placed on the thin substrate. It was supposed to be joined to each other. The heating of the shrinking element is performed by the heating element attached to the shrinking element as illustrated in FIG. 1 (E).

4 (A) to 4 (C) show the out-of-plane deformation obtained by the calculation simulation by FEM analysis under the condition that all the contractile elements are heated at 80 ° C. in the configuration of the above design conditions. The state of the thin deformed panel in which is generated is shown. When the displacement of the thin plate member was estimated, the displacement of the convexly protruding 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 makes it possible to realize a thin deformable panel that can be selectively deformed out of the plane.

By the way, when an element made of a shape memory alloy is used as the contraction element as described above, even if the heating is stopped after the contraction element is contracted by heating, the contraction element remains contracted unless tension is applied. Will be. In this regard, in the thin deformable panel having the above configuration, the thin substrate and the auxetic structural plate are made of steel plate or the like, and the out-of-plane deformation caused by the shrinkage of the shrinkage element is elastic deformation, so that the shrinkage occurs. After the heating of the element is stopped, the elastic force in the thin substrate and the auxetic structure plate acts in the direction of contraction so as to return the thin substrate and the auxetic structure plate in the direction of returning to the flat plate shape before deformation. As a result, the contractile element is stretched. Therefore, when the heating and stopping of the shrinking element are repeated, the out-of-plane deformation of the thin deformable panel and the return to the flat plate state are repeated. The stress required to return the contracted element in the state in which the memory shape is developed, that is, in the contracted state, to the state before contraction (returning stress to the original shape) is 15 to 15 of the normal contraction stress generated when the contraction element contracts. Since it is about 20%, the thickness and dimensions of the thin substrate and the autetic structure plate are preferably set so that the elastic force generated by the out-of-plane deformation in the thin substrate and the autetic structure plate can cover the stress for returning to the original shape. May be done.

The above-mentioned thin deformable panel that can be deformed out of the plane of the present embodiment can be used for various purposes. For example, as shown in FIG. 5A, the thin deformable panel P is a body surface (P) of the vehicle body for the purpose of changing aerodynamic characteristics, absorbing impact force, changing the design, and the like. It can be used as an out-of-plane deformation element (which deforms from Pm to Pm) or as an element of an interior member such as a dashboard in a vehicle. Further, as shown in FIG. 5B, the thin deformable panel P is used for sunshine tracking and anti-glare in structures such as solar panels, signs, and signboards in which the board SLB is attached to an upright support. It can be used as a driving element (deformed from P to Pm) for changing the orientation of the board SLB for the purpose of visual enhancement and the like. Further, as shown in FIG. 5C, the thin deformable panel P is used in a control surface member such as an aircraft wing outer panel 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), in the luggage transport or the drive device of the self-propelled robot, a plurality of thin deformation panels are arranged to appropriately develop out-of-plane deformation, and the luggage is loaded. It is also conceivable to develop a wave motion for transporting R and the like. It should be understood that in the use of thin deformable panels as described above, the mechanism for applying the deforming force to deform the panel out of the plane is arranged along the plane in or near the plane. The point is that the space to be secured outside the surface is greatly reduced.

Although the above description is made in relation to the embodiments of the present invention, many modifications and modifications can be easily made by those skilled in the art, and the present invention is limited to the embodiments exemplified above. It will be apparent that, without limitation, it applies to various devices without departing from the concept of the present invention.

Claims (1)

It is a thin deformable panel,
A thin substrate that can be deformed out of the plane,
A shrinking element having at least one shrinking element, the first end of which is joined onto the thin substrate and selectively shrinking between the first and second ends.
An out-of-plane deformable auxetic structural plate in the plane that extends along the first direction in the plane and intersects the pair of first edges facing each other in the first direction. It has an auxetic structure that extends along the second direction and is surrounded by a pair of second edges facing each other and extends in the second direction when extended in the first direction. At least one of the pair of second rims is joined to the second end of the shrink element, with at least a portion of the area between the rim not joined to the shrink element and the pair of first rims. Includes an auxetic structural plate bonded to the thin substrate.
Even if the contraction element contracts, the length from the first end of the contraction element to the second peripheral edge of the autetic structure plate to which the second end of the contraction element is not joined is not shortened. As described above, the position of the first end of the contractile element is constrained, and the amount of displacement of the distance between the pair of first peripheral edges of the organic structural plate is the pair of first when the organic structural plate is extended. When the contractile element contracts while 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 are used. A thin deformable panel that deforms out of the plane integrally with.

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