JP7396892B2 - soles and shoes - Google Patents

Description

TECHNICAL FIELD The present invention relates to a shoe sole equipped with a shock-absorbing material , and a shoe equipped with the shoe sole.

BACKGROUND ART Conventionally, various types of cushioning materials for mitigating impact have been known, and these various types of cushioning materials are used depending on the purpose. For example, in shoes, a cushioning material is sometimes provided on the sole of the shoe in order to reduce the impact that occurs when the user lands on the ground. As the cushioning material provided on the sole of the shoe, a member made of resin or rubber is generally used.

In recent years, shoes have been developed in which the sole is provided with a portion having a lattice structure or a web structure, and the cushioning performance is improved not only in terms of materials but also in terms of structure. An example of a document disclosing a shoe having a sole provided with a portion having a lattice structure is US Patent Publication No. 2018/0049514 (Patent Document 1).

On the other hand, Japanese Patent Application Publication No. 2017-527637 (Patent Document 2) describes three-dimensional objects manufactured using the three-dimensional additive manufacturing method as geometric objects such as polyhedrons with internal cavities and triple periodic minimal curved surfaces. It is stated that it is possible to manufacture a product with a thicker surface structure based on this, and it is disclosed that by constructing the three-dimensional object with an elastic material, it can be applied to the sole of a shoe, for example. ing.

US Patent Publication No. 2018/0049514 Special table 2017-527637 publication

Here, a cushioning material having a structure based on the above-mentioned geometric surface structure and adding thickness thereto has higher compression rigidity than a cushioning material including a portion having a lattice structure or a web structure. It has the structural feature of

However, when attempting to obtain high compression rigidity in a cushioning material with this structure, the weight of the cushioning material increases significantly because the wall thickness increases and the space factor also increases. There is a problem with this.

Therefore, the present invention was made in view of the above-mentioned problems , and an object of the present invention is to provide a shoe sole that is lightweight and includes a cushioning material with excellent cushioning performance, and a shoe that includes the sole. do.

The sole according to the present invention is provided with a cushioning material, and the cushioning material has a three-dimensional shape formed by a wall whose outer shape is defined by a pair of parallel curved surfaces as a unit structure. , includes a three-dimensional structure in which the unit structures are regularly and continuously repeatedly arranged in at least one direction, and the three-dimensional structure is a triple-periodic minimal curved surface with a thickness added thereto. Consisting of The above-mentioned cushioning material has a cushioning function when the cuboid-shaped space occupied by each of the above-mentioned unit structures is called a unit space, and the cushioning material receives a load among the three mutually orthogonal sides that define the above-mentioned unit space. The first side is the side extending along the axial direction that exhibits When the extending sides are respectively the second side and the third side, the length of the first side is L1, and the length of the longer side of the second side and the third side is L2. The condition of 1.1≦L1/L2≦4.0 is satisfied. In the shoe sole according to the present invention, the cushioning material is arranged such that the axial direction is perpendicular to the ground contact surface.

A shoe according to the present invention includes the above-described sole according to the present invention and an upper provided above the sole.

According to the present invention , it is possible to provide a sole that is lightweight and includes a cushioning material with excellent cushioning performance, and a shoe that includes the sole.

FIG. 2 is a partially cutaway perspective view of the cushioning material according to the first embodiment. FIG. 2 is a cross-sectional view of the cushioning material shown in FIG. 1. FIG. 2 is a graph showing the results of simulating the buffer performance of buffer materials according to Comparative Example 1 and Example 1. FIG. 7 is a schematic cross-sectional view showing the shape of main parts of cushioning materials according to first and second modified examples. FIG. 3 is a partially cutaway perspective view of a cushioning material according to a second embodiment. FIG. 7 is a partially cutaway perspective view of a cushioning material according to a third embodiment. FIG. 7 is a partially cutaway perspective view of a cushioning material according to Embodiment 4; 7 is a graph showing the results of simulating the buffer performance of buffer materials according to Comparative Example 2 and Example 2. FIG. 7 is a partially cutaway perspective view of a cushioning material according to a fifth embodiment. FIG. 7 is a partially cutaway perspective view of a cushioning material according to a sixth embodiment. FIG. 7 is a perspective view of a shoe sole and a shoe including the same according to a seventh embodiment. FIG. 12 is a side view of the sole shown in FIG. 11; FIG. 12 is a schematic diagram showing an example of the arrangement of cushioning materials in the sole shown in FIG. 11;

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the embodiments described below, the same or common parts are denoted by the same reference numerals in the drawings, and the description thereof will not be repeated.

(Embodiment 1)
FIG. 1 is a partially cutaway perspective view of the cushioning material according to the first embodiment. FIG. 2 is a cross-sectional view of the cushioning material along the line II-II shown in FIG. Hereinafter, with reference to FIGS. 1 and 2, a cushioning material 1A according to the present embodiment will be described.

As shown in FIGS. 1 and 2, the cushioning material 1A includes a three-dimensional structure S having a plurality of unit structures U (see especially FIG. 1). Each of the plurality of unit structures U has a three-dimensional shape formed by a wall 10 whose outer shape is defined by a pair of parallel curved surfaces.

Here, in FIG. 1, for ease of understanding, the reference numeral U is not attached to the unit structure in the strict sense, but the unit space in the rectangular parallelepiped shape that is the space occupied by the unit structure. It is attached to.

The plurality of unit structures U are arranged regularly and along each of the width direction (X direction shown in the figure), depth direction (Y direction shown in the figure), and height direction (Z direction shown in the figure). Arranged in a continuous repeating manner. 1 and 2, four unit structures U adjacent to each other in the width direction and depth direction and two unit structures U adjacent to each other in the height direction are extracted and shown.

In this embodiment, a cushioning material 1A including a large number of unit structures U in each of the width direction, depth direction, and height direction will be described as an example. The number of repetitions of the unit structures U in the horizontal direction is not particularly limited, as long as two or more unit structures U are arranged along at least one of these three directions.

Here, the cushioning material 1A according to the present embodiment is designed to exhibit a cushioning function in the height direction (Z direction shown in the figure). Therefore, the axial direction, which is the direction in which the cushioning material 1A exerts its cushioning function by receiving a load, coincides with the above-mentioned height direction.

Each of the plurality of unit structures U has a three-dimensional shape formed by the walls 10 as described above. Therefore, by connecting these plurality of unit structures U to each other in succession, the three-dimensional structure S is also constituted by an aggregate of these walls 10.

Here, the three-dimensional structure S included in the cushioning material 1A has a structure in which a thickness is added to a geometric surface structure. In the cushioning material 1A according to the present embodiment, the surface structure is a Schwartz P structure, which is a type of triple periodic minimal curved surface defined mathematically. Note that a minimal curved surface is defined as a curved surface having the smallest area among the curved surfaces having a given closed curve as a boundary.

As shown in FIG. 2, the three-dimensional structure S, which is based on the Schwartz P structure and is thickened, has a meandering cross-sectional shape when cut along a specific plane. It has a meandering part 11. In this embodiment, the specific plane is a plane that is perpendicular to the plane of paper and parallel to line II-II in FIG.

Due to the structure of the three-dimensional structure S, there are three types of meandering portions 11 in total: those extending along the width direction, those extending along the depth direction, and those extending along the height direction. However, here, we focus on the meandering portion 11 that appears in the cross section shown in FIG. 2 and extends along the height direction (ie, the Z direction).

This meandering portion 11 extending in the height direction has a plurality of direction change points 12 located along the height direction, and at the direction change points 12, an inward corner 13 and an outward corner are formed. 14 are provided respectively. Among these, the inward corner portion 13 is a portion that appears to have a concave shape on the surface of the wall 10 in the above cross-sectional shape, and the outward corner portion 14 is a convex portion on the surface of the wall 10 in the above cross-sectional shape. It is a part that appears to have a shape of . Here, the distance between the meandering portions 11 extending in the height direction varies depending on the position in the height direction, and the distance between the meandering portions 11 extending in the height direction varies depending on the position in the height direction. It becomes larger and smaller periodically.

As shown in FIG. 1, in the cushioning material 1A according to the present embodiment, the unit structure U has an elongated shape in the height direction. Specifically, among the three mutually orthogonal sides defining the unit space, which is a rectangular parallelepiped space occupied by each unit structure U, the side extending in the height direction (that is, the Z direction) is the first side. If the side extending in the width direction (i.e. X direction) is the second side and the side extending in the depth direction (i.e. Y direction) is the third side, then the first side is the longest. A unit structure U is constructed in . The first side, which is the longest side, is a side extending in the axial direction that is intended to exhibit the above-mentioned buffering function.

Here, in this embodiment, both the second side and the third side are adjusted to have the same length. Therefore, as shown in the figure, when the length of the first side is L1, and the lengths of the second and third sides are each L2, the cushioning material 1A according to the present embodiment has a length of 1.1 The condition of ≦L1/L2≦4.0 is satisfied.

With this configuration, it is possible to obtain a lightweight cushioning material with excellent cushioning performance, the details of which will be described later. In addition, if the length of the second side and the length of the third side are different, the length of the longer one of the second side and the third side is set as L2, and the above relational expression should be satisfied. .

Although the method for manufacturing the cushioning material 1A is not particularly limited, the cushioning material 1A can be manufactured, for example, by modeling using a three-dimensional additive manufacturing device.

The material of the cushioning material 1A may basically be any material as long as it is highly elastic, but preferably a resin material or a rubber material. More specifically, when the cushioning material 1A is made of resin, it may be made of thermoplastic resin such as ethylene-vinyl acetate copolymer (EVA), or may be made of, for example, polyurethane (PU). It can be a thermosetting resin. On the other hand, when the cushioning material 1A is made of rubber, it can be made of, for example, butadiene rubber.

The buffer material 1A can also be made of a polymer composition. In this case, examples of the polymer contained in the polymer composition include olefin polymers such as olefin elastomers and olefin resins. Examples of olefin polymers include polyethylene (for example, linear low density polyethylene (LLDPE), high density polyethylene (HDPE), etc.), polypropylene, ethylene-propylene copolymer, propylene-1-hexene copolymer, propylene-4 -Methyl-1-pentene copolymer, propylene-1-butene copolymer, ethylene-1-hexene copolymer, ethylene-4-methyl-pentene copolymer, ethylene-1-butene copolymer, 1- Butene-1-hexene copolymer, 1-butene-4-methyl-pentene, ethylene-methacrylic acid copolymer, ethylene-methyl methacrylate copolymer, ethylene-ethyl methacrylate copolymer, ethylene-butyl methacrylate Copolymer, ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate copolymer, ethylene-butyl acrylate copolymer, propylene-methacrylic acid copolymer, propylene-methyl methacrylate copolymer, propylene-ethyl methacrylate Copolymer, propylene-butyl methacrylate copolymer, propylene-methyl acrylate copolymer, propylene-ethyl acrylate copolymer, propylene-butyl acrylate copolymer, ethylene-vinyl acetate copolymer (EVA), propylene- Examples include polyolefins such as vinyl acetate copolymers.

Further, the polymer may be an amide polymer such as an amide elastomer or an amide resin. Examples of the amide polymer include polyamide 6, polyamide 11, polyamide 12, polyamide 66, polyamide 610, and the like.

Further, the polymer may be an ester polymer such as an ester elastomer or an ester resin. Examples of the ester polymer include polyethylene terephthalate and polybutylene terephthalate.

Further, the above-mentioned polymer may be a urethane-based polymer such as a urethane-based elastomer or a urethane-based resin. Examples of the urethane-based polymer include polyester-based polyurethane, polyether-based polyurethane, and the like.

Further, the polymer may be a styrene polymer such as a styrene elastomer or a styrene resin. Styrene-based elastomers include styrene-ethylene-butylene copolymer (SEB), styrene-butadiene-styrene copolymer (SBS), and hydrogenated product of SBS (styrene-ethylene-butylene-styrene copolymer (SEBS)). , styrene-isoprene-styrene copolymer (SIS), hydrogenated product of SIS (styrene-ethylene-propylene-styrene copolymer (SEPS)), styrene-isobutylene-styrene copolymer (SIBS), styrene-butadiene- Examples include styrene-butadiene (SBSB), styrene-butadiene-styrene-butadiene-styrene (SBSBS), and the like. Examples of the styrene resin include polystyrene, acrylonitrile styrene resin (AS), acrylonitrile butadiene styrene resin (ABS), and the like.

In addition, the above-mentioned polymers include, for example, acrylic polymers such as polymethyl methacrylate, urethane-based acrylic polymers, polyester-based acrylic polymers, polyether-based acrylic polymers, polycarbonate-based acrylic polymers, epoxy-based acrylic polymers, conjugated diene polymer-based acrylic polymers, and Hydrogenated products thereof, urethane-based methacrylic polymers, polyester-based methacrylic polymers, polyether-based methacrylic polymers, polycarbonate-based methacrylic polymers, epoxy-based methacrylic polymers, conjugated diene polymer-based methacrylic polymers, and their hydrogenated products, polyvinyl chloride-based resins, silicones elastomer, butadiene rubber (BR), isoprene rubber (IR), chloroprene (CR), natural rubber (NR), styrene butadiene rubber (SBR), acrylonitrile butadiene rubber (NBR), butyl rubber (IIR), etc. .

As described above, the cushioning material 1A according to the present embodiment is lightweight and has excellent cushioning performance. This is largely due to the structural characteristics (shape characteristics) of the cushioning material 1A. This point will be explained in detail below based on the results of the first verification test conducted by the inventor.

FIG. 3 is a graph showing the results of simulating the buffer performance of the buffer materials according to Comparative Example 1 and Example 1.

In the first verification test, we specifically designed models of the cushioning materials according to Comparative Example 1 and Example 1, and assumed that an external force was applied to these models along a predetermined direction. The behavior was individually analyzed by simulation. More specifically, so-called stress-strain curves were obtained for each of these models.

Here, the cushioning material according to Example 1 is the cushioning material 1A according to the present embodiment, and satisfies the above-mentioned condition of 1.1≦L1/L2≦4.0. On the other hand, although the cushioning material according to Comparative Example 1 has a configuration similar to that of the cushioning material 1A according to the present embodiment, it does not satisfy the above-mentioned condition of 1.1≦L1/L2≦4.0.

More specifically, in the cushioning material according to Comparative Example 1, the width direction, depth direction, and height direction of the unit structure U are each 10 mm, and L1/L2 is 1. It is 0. Note that the thickness of the wall 10 is 2.36 mm, and the space factor V in that case is about 50%.

On the other hand, in the cushioning material according to Example 1, the width direction and depth direction of the unit structure U are each 5 mm, and the height direction is 10 mm, and L1/L2 is 2. It is 0. Note that the thickness of the wall 10 is 1.36 mm, and the space factor V in that case is about 50%.

Further, the direction of the external force applied to the cushioning materials according to Comparative Example 1 and Example 1 was both the height direction, which is the axial direction mentioned above. In addition, the material of the cushioning material according to Comparative Example 1 and Example 1 was assumed to be a urethane-based acrylic polymer having an elastic modulus of 0.5 MPa.

Here, when increasing the compression rigidity in order to improve the cushioning performance, it is usually considered to increase the thickness of the wall 10 of the unit structure U. However, if the thickness of the wall 10 is increased, the space factor V will also increase accordingly, so the thicker the wall 10 is, the larger the space factor V will be, and the heavier the cushioning material will be. I end up. In other words, there is a so-called trade-off relationship between ensuring compression rigidity and reducing weight.

However, as shown in FIG. 3, although the cushioning material according to Example 1 has the same space factor as the cushioning material according to Comparative Example 1, it has a higher compression rigidity than the cushioning material according to Comparative Example 1. have. This is considered to be because the compressive rigidity was increased by making the wall 10 act more like a screen as the length in the width direction of the unit structure U was shortened.

Therefore, according to the results of the first verification test, by using the cushioning material according to Example 1, it is possible to obtain high compressive rigidity with a smaller space factor (that is, without increasing the thickness of the wall 10). As a result, it can be seen that a lightweight cushioning material with excellent cushioning performance can be obtained.

Therefore, by using the cushioning material 1A according to the present embodiment described above, it is possible to obtain a lightweight cushioning material that can be used for various purposes and has excellent cushioning performance.

(First and second variations)
FIG. 4(A) and FIG. 4(B) are schematic cross-sectional views showing the shapes of main parts of the cushioning materials according to the first and second modified examples, respectively. Hereinafter, with reference to FIGS. 4(A) and 4(B), cushioning materials 1A1 and 1A2 according to first and second modified examples based on the first embodiment described above will be described.

As shown in FIG. 4(A), a cushioning material 1A1 according to the first modification is provided with a plurality of additional thickness portions 15 at predetermined positions on the wall 10. As shown in FIG. Each of the plurality of additional thickness portions 15 is provided in a projecting shape at the inside corner portion 13 of the direction change point 12 of the meandering portion 11 . Further, each of the plurality of additional thickness portions 15 extends across the inner corner portion 13.

The additional thickness portion 15 is provided to increase the thickness of the direction change point 12 compared to other portions, and when an external force is applied to the cushioning material 1A1, large deformation occurs and stress is concentrated. It functions as a reinforcing part that reinforces the easy direction change point 12. Therefore, by providing this additional thickness portion 15, it is possible to ensure higher compression rigidity, and after a certain degree of deformation occurs at the direction change point 12 due to the application of external force, further deformation at the direction change point 12 is prevented. is physically obstructed by the additional thickness portion 15, thereby suppressing the occurrence of stress concentration at the direction change point 12.

As shown in FIG. 4(B), a cushioning material 1A2 according to the second modification is provided with a plurality of additional thickness portions 15' at predetermined positions on the wall 10. Each of the plurality of additional thickness portions 15' does not have a protruding shape, unlike the additional thickness portion 15 of the above-mentioned cushioning material 1A1, and each of the plurality of additional thickness portions 15' does not have a protruding shape, and is located at the direction change point 12 of the meandering portion 11. It is provided so as to embed the inside corner part 13. Further, each of the plurality of additional thickness portions 15' extends across the inner corner portion 13.

The additional thickness part 15' is provided to increase the thickness of the direction change point 12 compared to other parts, and when an external force is applied to the cushioning material 1A1, large deformation occurs and stress is reduced. It functions as a reinforcing part that reinforces the direction change point 12 where concentration is likely to occur. Therefore, by providing this additional thickness part 15', it is possible to ensure higher compression rigidity, and after a certain degree of deformation occurs at the direction change point 12 due to the application of external force, the Since deformation is physically inhibited by the additional thickness portion 15', stress concentration at the direction change point 12 can be suppressed.

Although a detailed explanation thereof will be omitted here, the cushioning materials 1A1 and 1A2 according to the first and second modified examples also satisfy the above-mentioned condition of 1.1≦L1/L2≦4.0.

Therefore, when the cushioning materials 1A1 and 1A2 according to the first and second modified examples are used, in addition to the effects obtained when the cushioning materials 1A according to the first embodiment described above are used, stress is further concentrated locally. As a result, the durability of the cushioning material is improved, and the compression rigidity can be further improved.

(Embodiment 2)
FIG. 5 is a partially cutaway perspective view of the cushioning material according to the second embodiment. Hereinafter, with reference to FIG. 5, the cushioning material 1B according to the present embodiment will be described.

As shown in FIG. 5, the cushioning material 1B includes a three-dimensional structure S having a plurality of unit structures U. Each of the plurality of unit structures U has a three-dimensional shape formed by a wall 10 whose outer shape is defined by a pair of parallel curved surfaces.

The plurality of unit structures U are arranged regularly and along each of the width direction (X direction shown in the figure), depth direction (Y direction shown in the figure), and height direction (Z direction shown in the figure). Arranged in a continuous repeating manner. In FIG. 5, four unit structures U adjacent to each other in the width direction and depth direction and two unit structures U adjacent to each other in the height direction are extracted and shown.

As described above, each of the plurality of unit structures U has a three-dimensional shape formed by the walls 10. Therefore, by connecting these plurality of unit structures U to each other in succession, the three-dimensional structure S is also constituted by an aggregate of these walls 10.

Here, the three-dimensional structure S included in the cushioning material 1B has a structure in which a thickness is added to a geometric surface structure. In the cushioning material 1B according to the present embodiment, the surface structure is a gyroid structure which is a type of triple periodic minimal curved surface defined mathematically.

In the cushioning material 1B according to the present embodiment, the lengths L1 and L2 of the first side to the third side defining the unit space, which is a rectangular parallelepiped space occupied by each unit structure U (this embodiment (The lengths of the second side and the third side are the same also in the form), but as in the case of the first embodiment described above, the condition of 1.1≦L1/L2≦4.0 is satisfied. .

Therefore, in the case of the cushioning material 1B according to the present embodiment, as in the case of the first embodiment described above, the cushioning material is lightweight and has excellent cushioning performance and can be used for various purposes. be able to.

(Embodiment 3)
FIG. 6 is a partially cutaway perspective view of the cushioning material according to the third embodiment. Hereinafter, with reference to FIG. 6, the cushioning material 1C according to the present embodiment will be described.

As shown in FIG. 6, the cushioning material 1C includes a three-dimensional structure S having a plurality of unit structures U. Each of the plurality of unit structures U has a three-dimensional shape formed by a wall 10 whose outer shape is defined by a pair of parallel curved surfaces.

The plurality of unit structures U are arranged regularly and along each of the width direction (X direction shown in the figure), depth direction (Y direction shown in the figure), and height direction (Z direction shown in the figure). Arranged in a continuous repeating manner. In FIG. 6, eight unit structures U adjacent to each other in the width direction and depth direction and four unit structures U adjacent to each other in the height direction are extracted and shown.

As described above, each of the plurality of unit structures U has a three-dimensional shape formed by the walls 10. Therefore, by connecting these plurality of unit structures U to each other in succession, the three-dimensional structure S is also constituted by an aggregate of these walls 10.

Here, the three-dimensional structure S included in the cushioning material 1C has a structure in which a thickness is added to a geometric surface structure. In the cushioning material 1C according to the present embodiment, the surface structure is a Schwartz D structure, which is a type of triple periodic minimal curved surface defined mathematically.

In the cushioning material 1C according to the present embodiment, the lengths L1 and L2 of the first side to the third side defining the unit space, which is a rectangular parallelepiped space occupied by each unit structure U (this embodiment (The lengths of the second side and the third side are the same also in the form), but as in the case of the first embodiment described above, the condition of 1.1≦L1/L2≦4.0 is satisfied. .

Therefore, in the case of the cushioning material 1C according to the present embodiment, as in the case of the first embodiment described above, the cushioning material is lightweight and has excellent cushioning performance and can be used for various purposes. be able to.

(Embodiment 4)
FIG. 7 is a partially cutaway perspective view of the cushioning material according to the fourth embodiment. Hereinafter, with reference to FIG. 7, the cushioning material 1D according to the present embodiment will be described.

As shown in FIG. 7, the cushioning material 1D includes a three-dimensional structure S having a plurality of unit structures U. Each of the plurality of unit structures U has a three-dimensional shape formed by a wall 10 whose outer shape is defined by a pair of parallel planes.

The plurality of unit structures U are arranged regularly and along each of the width direction (X direction shown in the figure), depth direction (Y direction shown in the figure), and height direction (Z direction shown in the figure). Arranged in a continuous repeating manner. In FIG. 7, only two unit structures U that are adjacent to each other in the width direction and the depth direction are extracted and shown.

As described above, each of the plurality of unit structures U has a three-dimensional shape formed by the walls 10. Therefore, by connecting these plurality of unit structures U to each other in succession, the three-dimensional structure S is also constituted by an aggregate of these walls 10.

Here, the three-dimensional structure S included in the cushioning material 1D has a structure in which a thickness is added to a geometric surface structure. In the cushioning material 1D according to the present embodiment, the surface structure is a cubic octet structure consisting of a plurality of planes arranged to intersect with each other so as to have a cavity inside.

In the cushioning material 1D according to the present embodiment, the lengths L1 and L2 of the first side to the third side defining the unit space, which is a rectangular parallelepiped space occupied by each unit structure U (this embodiment (The lengths of the second side and the third side are the same also in the form), but as in the case of the first embodiment described above, the condition of 1.1≦L1/L2≦4.0 is satisfied. .

FIG. 8 is a graph showing the results of simulating the buffer performance of the buffer materials according to Comparative Example 2 and Example 2. Hereinafter, with reference to FIG. 8, a second verification test will be described in which the effects obtained when using the cushioning material 1D according to the present embodiment were verified.

In the second verification test, models of the cushioning materials according to Comparative Example 2 and Example 2 were specifically designed, and it was assumed that an external force was applied to these models along a predetermined direction. The behavior was individually analyzed by simulation. More specifically, so-called stress-strain curves were obtained for each of these models.

Here, the cushioning material according to Example 2 is the cushioning material 1D according to the present embodiment itself, and satisfies the above-mentioned condition of 1.1≦L1/L2≦4.0. On the other hand, although the cushioning material according to Comparative Example 2 has a configuration similar to that of the cushioning material 1A according to the present embodiment, it does not satisfy the above-mentioned condition of 1.1≦L1/L2≦4.0.

More specifically, in the cushioning material according to Comparative Example 2, the width direction, depth direction, and height direction of the unit structure U are each 20 mm, and L1/L2 is 1. It is 0. Note that the thickness of the wall 10 is 1.6 mm, and the space factor V in that case is about 50%.

On the other hand, in the cushioning material according to Example 2, the width direction and depth direction of the unit structure U are each 10 mm, and the height direction is 20 mm, and L1/L2 is 2. It is 0. Note that the thickness of the wall 10 is 0.8 mm, and the space factor V in that case is about 50%.

Further, the direction of the external force applied to the cushioning materials according to Comparative Example 2 and Example 2 was both the above-mentioned axial direction, which is the height direction. In addition, the material of the cushioning material according to Comparative Example 2 and Example 2 was assumed to be a urethane-based acrylic polymer having an elastic modulus of 9 MPa.

As shown in FIG. 8, although the cushioning material according to Example 2 has the same space factor as the cushioning material according to Comparative Example 2, it has higher compression rigidity than the cushioning material according to Comparative Example 2. It was confirmed that This is thought to be because, as in the case of the first verification test, the length in the width direction of the unit structure U was shortened, and the wall 10 acted more like a screen, increasing the compressive rigidity. .

Therefore, by using the cushioning material 1D according to the present embodiment described above, it is possible to obtain a lightweight cushioning material with excellent cushioning performance that can be used for various purposes.

(Embodiment 5)
FIG. 9 is a partially cutaway perspective view of the cushioning material according to the fifth embodiment. The cushioning material 1E according to this embodiment will be described below with reference to FIG. 9.

As shown in FIG. 9, the cushioning material 1E includes a three-dimensional structure S having a plurality of unit structures U. Each of the plurality of unit structures U has a three-dimensional shape formed by a wall 10 whose outer shape is defined by a pair of parallel planes.

The plurality of unit structures U are arranged regularly and along each of the width direction (X direction shown in the figure), depth direction (Y direction shown in the figure), and height direction (Z direction shown in the figure). Arranged in a continuous repeating manner. In FIG. 9, only two unit structures U that are adjacent to each other in the width direction and the depth direction are extracted and shown.

As described above, each of the plurality of unit structures U has a three-dimensional shape formed by the walls 10. Therefore, by connecting these plurality of unit structures U to each other in succession, the three-dimensional structure S is also constituted by an aggregate of these walls 10.

Here, the three-dimensional structure S included in the cushioning material 1E has a structure in which a thickness is added to a geometric surface structure. In the cushioning material 1E according to the present embodiment, the surface structure is a cubic structure consisting of a plurality of planes arranged to intersect with each other so as to have a cavity inside.

In the cushioning material 1E according to the present embodiment, the lengths L1 and L2 of the first side to the third side defining the unit space which is a rectangular parallelepiped space occupied by each unit structure U (this embodiment (The lengths of the second side and the third side are the same also in the form), but as in the case of the first embodiment described above, the condition of 1.1≦L1/L2≦4.0 is satisfied. .

Therefore, in the case of the cushioning material 1E according to the present embodiment, as in the case of the first embodiment described above, the cushioning material is lightweight and has excellent cushioning performance and can be used for various purposes. be able to.

(Embodiment 6)
FIG. 10 is a partially cutaway perspective view of the cushioning material according to the sixth embodiment. Hereinafter, with reference to FIG. 10, the cushioning material 1F according to the present embodiment will be described.

As shown in FIG. 10, the cushioning material 1F includes a three-dimensional structure S having a plurality of unit structures U. Each of the plurality of unit structures U has a three-dimensional shape formed by a wall 10 whose outer shape is defined by a pair of parallel planes.

The plurality of unit structures U are arranged regularly and along each of the width direction (X direction shown in the figure), depth direction (Y direction shown in the figure), and height direction (Z direction shown in the figure). Arranged in a continuous repeating manner. In FIG. 10, only two unit structures U that are adjacent to each other in the width direction and the depth direction are extracted and shown.

As described above, each of the plurality of unit structures U has a three-dimensional shape formed by the walls 10. Therefore, by connecting these plurality of unit structures U to each other in succession, the three-dimensional structure S is also constituted by an aggregate of these walls 10.

Here, the three-dimensional structure S included in the cushioning material 1F has a structure in which a thickness is added to the geometric surface structure. In the cushioning material 1F according to the present embodiment, the surface structure is an octet structure consisting of a plurality of planes arranged to intersect with each other so as to have a cavity inside.

In the cushioning material 1F according to the present embodiment, the lengths L1 and L2 of the first side to the third side defining the unit space, which is a rectangular parallelepiped space occupied by each unit structure U (this embodiment (The lengths of the second side and the third side are the same also in the form), but as in the case of the first embodiment described above, the condition of 1.1≦L1/L2≦4.0 is satisfied. .

Therefore, when the cushioning material 1F according to this embodiment is used, as in the case of the first embodiment described above, the cushioning material is lightweight and has excellent cushioning performance and can be used for various purposes. be able to.

(Embodiment 7)
FIG. 11 is a perspective view of a shoe sole and a shoe including the same according to Embodiment 7, and FIG. 12 is a side view of the shoe sole shown in FIG. 11. Moreover, FIG. 13 is a schematic diagram showing an example of the arrangement of cushioning materials in the sole shown in FIG. 11. Here, FIG. 13(A) is a schematic cross-sectional view of the shoe sole along the line XIIIA-XIIIA shown in FIG. 12. Hereinafter, a shoe sole 110 according to the present embodiment and a shoe 100 including the same will be described with reference to FIGS. 11 to 13. Note that the sole 110 according to the present embodiment includes the cushioning material 1A according to the first embodiment described above.

As shown in FIG. 11, the shoe 100 includes a sole 110 and an upper 120. The sole 110 is a member that covers the sole of the foot, and has a substantially flat shape. The upper 120 has a shape that covers at least the entire part of the instep side of the inserted foot, and is located above the sole 110.

The upper 120 includes an upper main body 121, a shoe tongue 122, and a shoelace 123. Of these, the shoe tongue 122 and the shoelace 123 are both fixed or attached to the upper main body 121.

The upper body 121 has an upper opening that exposes the upper part of the ankle and part of the instep. On the other hand, the lower part of the upper body 121 is provided with, for example, a lower opening that is covered by the sole 110, and as another example, the lower end of the upper body 121 may be sewn to form a bottom part. is formed.

The tongue 122 is fixed to the upper body 121 by sewing, welding, gluing, or a combination thereof so as to cover a part of the upper opening provided in the upper body 121 that exposes a part of the instep of the foot. . For the upper body 121 and the tongue 122, for example, woven fabric, knitted fabric, non-woven fabric, synthetic leather, resin, etc. are used. For shoes where breathability and lightness are particularly required, double raschel warp knitted fabric woven with polyester yarn is used. used.

The shoelace 123 is made of a string-like member for drawing the periphery of an upper opening provided in the upper body 121 that exposes a part of the instep of the foot toward each other in the foot width direction, and is provided on the periphery of the upper opening. It is inserted through a plurality of holes. By tightening the shoelaces 123 while the foot is inserted into the upper body 121, it becomes possible to bring the upper body 121 into close contact with the foot.

As shown in FIGS. 11 to 13, the sole 110 includes a midsole 111, an outsole 112, and a cushioning material 1A. The midsole 111 is located above the sole 110 and is joined to the upper 120. The outsole 112 has a ground contact surface 112a (see FIG. 12) on its lower surface, and is located below the sole 110. The cushioning material 1A is interposed at a predetermined position between the midsole 111 and the outsole 112.

It is preferable that the midsole 111 has moderate strength and excellent cushioning properties, and from this point of view, the midsole 111 can be made of, for example, a foam material made of resin or rubber, which is particularly suitable. The material may be a foam material made of a thermoplastic resin such as ethylene-vinyl acetate copolymer (EVA), a thermosetting resin such as polyurethane (PU), or butadiene rubber.

It is preferable that the outsole 112 has excellent abrasion resistance and grip properties, and from this point of view, the outsole 112 can be made of rubber, for example. Note that a tread pattern may be provided on the contact surface 112a, which is the lower surface of the outsole 112, from the viewpoint of improving the grip described above.

As shown in FIG. 12, the sole 110 includes a forefoot portion that supports the toes and the stepping portion of the foot along the longitudinal direction (left-right direction in the figure), which is the long axis direction when viewed from above. R1, a middle foot part R2 that supports the non-stepping part of the foot, and a rear foot part R3 that supports the heel part of the foot. Further, as shown in FIG. 13(A), the sole 110 is placed on the midline side of the foot in the anatomical normal position along the width direction of the foot, which is a direction that intersects with the long axis direction when viewed from above. (i.e., the side close to the midline) (the S1 side part shown in the figure), and the side of the foot opposite to the median side in the anatomical normal position (i.e., the side far from the midline). It is divided into a certain outer leg side part (S2 side part shown in the figure).

Here, in the shoe 100 according to the present embodiment, the midsole 111 is provided with a notch portion of a predetermined shape, and the cushioning material 1A is accommodated in the notch portion. is fixed between the midsole 111 and the outsole 112 in the thickness direction of the sole 110.

Specifically, as shown in FIGS. 12 and 13(A), the midsole 111 has a groove extending along the periphery of the sole 110 across the middle foot R2 and the rear foot R3 in a plan view. A U-shaped notch is provided, and a cushioning material 1A having a substantially U-shape in plan view as a whole is arranged so as to embed the notch. More specifically, the cushioning material 1A covers the medial edge of the midfoot R2, the medial edge of the hindfoot R3, the rear edge of the hindfoot R3, and the medial edge of the hindfoot R3. It is arranged along the edge on the outer foot side and the edge on the outer foot side of the midfoot portion R2.

As explained in the above-mentioned Embodiment 1, the material of the cushioning material 1A is not particularly limited, but may be, for example, a resin material or a rubber material, and particularly preferably ethylene-vinyl acetate. It can be a thermoplastic resin such as a copolymer (EVA), a thermosetting resin such as polyurethane (PU), butadiene rubber, or the like. Further, polymer compositions such as olefin polymers, amide polymers, ester polymers, urethane polymers, styrene polymers, and acrylic polymers can also be used.

Here, as shown in FIG. 12, the cushioning material 1A is arranged so that its height direction (Z direction shown in the figure), which is the above-mentioned axial direction, is perpendicular to the ground plane 112a of the sole 110. . With this configuration, when landing, the load applied to the sole 110 from the sole and the ground is absorbed by the cushioning material 1A deforming with a large amount of deformation, and the load is applied from the sole 110 to the sole of the foot. This results in a reduction in the applied load and a high buffering performance.

Further, although a detailed explanation thereof will be omitted here, the cushioning material 1A satisfies the above-mentioned conditions of 1.1≦L1/L2≦4.0, so it has high compression rigidity, is lightweight, and has a cushioning effect. It has excellent performance.

Therefore, by using the sole 110 according to the present embodiment and the shoe 100 including the same, it is possible to obtain a lightweight shoe sole with excellent cushioning performance and a shoe including the same.

Note that the cushioning material 1A may be formed into the above-described substantially U-shape in plan view as a whole by combining and bonding a plurality of mutually independent members, but it is more preferable. It is preferable that the entire portion is formed as a single member so that it is formed into the above-mentioned substantially U-shape in plan view. In particular, when adopting the latter configuration, how can the cushioning material 1A, which includes a plurality of unit structures U each having a rectangular parallelepiped shape, fit into a non-rectangular parallelepiped-shaped notch while eliminating unevenness in cushioning performance from one part to another? The layout is important.

Hereinafter, with reference to FIGS. 13(A) to 13(E), a rectangular parallelepiped-shaped unit space (particularly in this embodiment, the length of the second side and the length of the third side are the same L2, A cushioning material comprising a plurality of unit structures U occupying an elongated rectangular parallelepiped-shaped unit space whose first side length L1 is larger than these, a part or all of the plurality of unit structures U, We will explain a specific design method that makes it possible to layout in a non-rectangular parallelepiped area while eliminating bias in cushioning performance from part to part by only making slight changes to the shape without major changes. do.

First, as shown in FIG. 13(A), while adjusting the size of the unit structures U in the area where the cushioning material is arranged, the number of the unit structures U is adjusted in the width direction, depth direction and height. The area A1 is divided into an area A1 where it is possible to arrange the images as they are by increasing or decreasing the size in at least one of the horizontal directions, and an area A2 where it is difficult to do so. Specifically, in the present embodiment, of the area where the cushioning material 1A is arranged, the area extending linearly along the periphery of the inner foot side and the outer foot side of the sole 110 is the area where the cushioning material 1A is arranged. A region corresponding to A1 and extending in a curved shape along the peripheral edge of the rear end side of the sole 110 corresponds to the above-mentioned region A2.

Here, in area A1, as shown in FIG. 13(B), a unit space consisting of a rectangular parallelepiped shape with the length of the first side adjusted to L1 and the lengths of the second and third sides adjusted to L2 is defined. A plurality of occupied unit structures U are arranged adjacent to each other. As a result, the area A1 is covered with a plurality of unit structures U whose sizes are adjusted without any gaps.

On the other hand, in area A2, as shown in FIG. 13(C), a specific pair of surfaces among the three pairs of opposing surfaces occupy a unit space whose shape has been changed so that they are non-parallel to each other. A plurality of unit structures U' configured as shown in FIG. 1 are arranged adjacent to each other. Here, in the unit structure U', for example, a pair of adjacent sides among the four sides (i.e., second sides) of the unit space extending in the width direction is slightly longer than the length L2 of the other side. The shape has been changed so as to occupy the adjusted unit space, which has been adjusted to have a short L2'. Such a slight change in shape does not significantly change the cushioning performance of the unit structure.

Note that the unit structures U' having such a shape can be arranged side by side while adjusting their sizes and directions individually, so that the unit structures U' can be arranged along the above-mentioned area A2, which is an area extending in a curved shape. This can be spread almost completely without any gaps. Therefore, by only making such a slight change in shape, the same buffering performance as in the above-mentioned region A1 can be exhibited in the region A2 as well.

Therefore, by adopting this design method, a cushioning material including a plurality of unit structures U occupying a unit space in the shape of a rectangular parallelepiped can be manufactured by significantly changing the shape of some or all of the plurality of unit structures U. By only slightly changing the shape without any turbulence, it becomes possible to lay out in a non-rectangular parallelepiped area while eliminating deviations in cushioning performance from part to part.

Therefore, if a cushioning material is designed according to the design method and then manufactured using a three-dimensional additive manufacturing device based on this design method, the external shape of the cushioning material, which is constructed as a single piece, can be made into various shapes. Cushioning material can be easily obtained.

In addition, in the above-mentioned design method, when covering an area with a more complicated curved shape with cushioning material, two specific sets of faces out of three sets of opposing faces as shown in FIG. 13(D) A plurality of unit structures U1 configured to occupy unit spaces whose shapes are changed so as to be non-parallel to each other may be arranged adjacent to each other.

Here, in the unit structure U1, for example, a pair of adjacent sides among the four sides (i.e., the second side) of the unit space extending in the width direction is slightly shorter than the length L2 of the other side. In addition, for example, a pair of adjacent sides of the four sides (i.e., the first side) of the unit space extending in the height direction is slightly smaller than the length L1 of the other side. The shape is changed to occupy the unit space after the adjustment, which is adjusted to have a shorter L1'. Such a slight change in shape does not significantly change the cushioning performance of the unit structure.

The unit structures U1 having such a shape can be arranged side by side while adjusting their size and orientation individually, so that they can be spread almost without gaps along the area of the above-mentioned complex curved shape. I can do it. Therefore, by only making such a slight change in shape, the same buffering performance as in the above-mentioned region A1 can be exhibited in this region as well.

In addition, in the above-described design method, when covering a linearly extending area with cushioning material, instead of the unit structure U as shown in FIG. 13(B), a unit structure as shown in FIG. 13(E) is used. A plurality of bodies U2 may be arranged adjacent to each other. Here, the unit structure U2 occupies the adjusted unit space in which the shape of a specific set of surfaces is adjusted to be a parallelogram while the three pairs of opposing surfaces are parallel. The shape has been changed as follows.

In the illustrated unit structure U2, for example, by inclining each of a pair of surfaces located in the height direction along the width direction by an angle θ, the shape of the pair of surfaces is made into a parallelogram. ing. Such a slight change in shape does not significantly change the cushioning performance of the unit structure. Therefore, even when the unit structures U2 are laid out, it is possible to lay out the cushioning materials without gaps while eliminating unevenness in the cushioning performance for each part.

(Summary of disclosure contents in embodiments, etc.)
The characteristic configurations disclosed in the first to seventh embodiments and their modifications described above are summarized as follows.

A cushioning material according to an aspect of the present disclosure has a three-dimensional shape formed by a wall whose outer shape is defined by a pair of parallel planes or curved surfaces as a unit structure, and the unit structure is regular in at least one direction. It includes three-dimensional structures that are arranged repeatedly and continuously. In the cushioning material according to an aspect of the present disclosure, the rectangular parallelepiped space occupied by each of the unit structures is referred to as a unit space, and the cushioning material The first side is the side extending along the axial direction that exhibits a buffering function when subjected to a load, and among the three mutually orthogonal sides defining the unit space, from one end of the first side to the axis The sides extending along the direction orthogonal to the direction are respectively the second side and the third side, the length of the first side is L1, and the longer side of the second side and the third side. When the length of is L2, the condition of 1.1≦L1/L2≦4.0 is satisfied.

In the cushioning material according to an aspect of the present disclosure, each of the unit spaces arranged along the axial direction may have the same L1/L2.

In the cushioning material according to an aspect of the present disclosure, the three-dimensional structure may be formed by adding thickness to a triple periodic minimum curved surface.

In the cushioning material according to an aspect of the present disclosure, the three-dimensional structure may have a Schwartz P structure, a gyroid structure, or a Schwartz D structure.

In the cushioning material according to an aspect of the present disclosure, the three-dimensional structure has a meandering portion where a cross-sectional shape extending in a meandering manner appears when cut along at least a specific plane. In that case, the meandering portion may have a reinforcing portion that reinforces the turning point of the meandering portion. Further, in that case, the reinforcing portion may include an additional thickness portion provided at the corner of the direction change point to increase the thickness of the direction change point compared to other portions. Good too.

In the cushioning material according to an aspect of the present disclosure, the three-dimensional structure has a thickness based on a plurality of planes arranged to intersect with each other so that the three-dimensional structure has a cavity inside. It may be composed of the following.

In the cushioning material according to an aspect of the present disclosure, the three-dimensional structure may have a cubic structure, an octet structure, or a cubic octet structure.

The cushioning material according to an aspect of the present disclosure may be made of either a resin material or a rubber material.

The buffer material according to an embodiment of the present disclosure is one selected from the group consisting of an olefin polymer, an amide polymer, an ester polymer, a urethane polymer, a styrene polymer, an acrylic polymer, and a methacrylic polymer. It may be composed of a polymer composition containing more than one species.

A shoe sole according to an aspect of the present disclosure includes the above-described cushioning material according to an aspect of the present disclosure.

In the shoe sole according to an aspect of the present disclosure, the cushioning material may be arranged such that the axial direction is perpendicular to the ground contact surface.

A shoe according to an aspect of the present disclosure includes a sole according to an aspect of the present disclosure described above, and an upper provided above the sole.

(Other forms, etc.)
In Embodiment 7 described above, the case where the cushioning material according to Embodiment 1 is applied to a shoe sole and a shoe equipped with the same has been explained as an example, but instead of this, Embodiment 2 or The cushioning material according to No. 6 or the cushioning materials according to the first and second modifications based on Embodiment 1 may be applied to a shoe sole and a shoe equipped with the same.

Furthermore, in the seventh embodiment described above, the case where the cushioning material is arranged along the periphery of the midfoot and rear side of the sole has been explained as an example, but the position where the cushioning material is provided is as follows. It is not limited and can be changed as appropriate. For example, the cushioning material may be provided on the entire surface of the sole, or a plurality of independent cushioning materials may be provided separately at predetermined positions on the sole. Furthermore, depending on the type of competition or purpose in which the shoe is used, a cushioning material may be placed only on either the inner foot side portion or the outer foot side portion of the sole. Furthermore, the cushioning material may be provided between the midsole and the upper. Here, when the cushioning material is provided on the entire surface of the sole, the entirety of the midsole may be replaced with the cushioning material.

Further, the thickness of the wall of the cushioning material may be made to vary depending on its position relative to the sole of the shoe, and the surface structure of the cushioning material may be made to vary depending on its position relative to the sole of the shoe. For example, a cushioning material whose surface structure is a Schwartz P structure may be placed in a certain part of the sole, and a cushioning material whose surface structure is a gyroid structure is placed in another part of the sole. good.

Furthermore, in the seventh embodiment described above, the case where the cushioning material according to the present invention is applied to the sole of a shoe is explained as an example, but the cushioning material according to the present invention can also be used for other cushioning purposes. can be used. For example, the cushioning material according to the present invention can be used for various purposes such as packaging materials, flooring materials for buildings (for example, houses, etc.), surface materials for paved roads, surface materials for sofas and chairs, tires, etc. can.

Further, the characteristic configurations disclosed in the first to seventh embodiments and their modifications described above can be combined with each other without departing from the spirit of the present invention.

In this way, the embodiments and their modifications disclosed herein are illustrative in all respects and are not restrictive. The technical scope of the present invention is defined by the claims, and includes all changes within the meaning and scope equivalent to the claims.

1A to 1C, 1A1, 1A2 Cushioning material, 10 Wall, 11 Meandering part, 12 Turning point, 13 Inner corner, 14 Outer corner, 15, 15' Additional thickness part, 16 Through hole, 20 Reinforcement part, 100 Shoes , 110 sole, 111 midsole, 112 outsole, 112a ground plane, 120 upper, 121 upper main body, 122 tongue, 123 shoe lace, R1 forefoot, R2 midfoot, R3 hindfoot, S three-dimensional structure, U, U', U1, U2 unit structure.

Claims (7)

A shoe sole equipped with a cushioning material,
The cushioning material has a unit structure having a three-dimensional shape formed by a wall whose outer shape is defined by a pair of parallel curved surfaces , and the unit structures are regularly and continuously repeatedly arranged in at least one direction. Including three-dimensional structures formed by
The three-dimensional structure is made of a triple periodic minimal curved surface with a thickness added thereto,
A rectangular parallelepiped-shaped space occupied by each of the unit structures is called a unit space, and the cushioning material receives a load from among the three mutually orthogonal sides that define the unit space, thereby achieving a buffering function. The side that extends along the axial direction that exhibits the When the extending sides are respectively the second side and the third side, the length of the first side is L1, and the length of the longer side of the second side and the third side is L2. , satisfies the condition of 1.1≦L1/L2≦4.0,
A shoe sole, wherein the cushioning material is arranged so that the axial direction is perpendicular to a ground plane . The sole according to claim 1, wherein each of the unit spaces arranged along the axial direction has the same L1/L2. The shoe sole according to claim 1 or 2 , wherein the three-dimensional structure has a Schwartz P structure, a gyroid structure, or a Schwartz D structure. The three-dimensional structure has a meandering part that is a part where a cross-sectional shape extending in a meandering manner appears when cut along at least a specific plane,
The meandering portion has a reinforcing portion that reinforces a direction change point of the meandering portion,
4. The reinforcing portion is constituted by an additional thickness portion provided at an inner corner of the direction change point in order to increase the thickness of the direction change point compared to other parts. Shoe sole . The shoe sole according to any one of claims 1 to 4 , comprising either a resin material or a rubber material. A claim consisting of a polymer composition containing one or more selected from the group consisting of olefin polymers, amide polymers, ester polymers, urethane polymers, styrene polymers, acrylic polymers, and methacrylic polymers. 5. The sole according to item 5 . A shoe sole according to any one of claims 1 to 6 ,
and an upper provided above the sole.

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