JP7389026B2 - Porous structure, porous structure manufacturing method, and 3D printing data - Google Patents

Description

The present invention relates to a porous structure, a method for manufacturing the porous structure, and 3D printing data.
This application has priority based on Japanese Patent Application No. 2018-108121 filed in Japan on June 5, 2018, and priority based on Japanese Patent Application No. 2018-226833 filed in Japan on December 3, 2018. , the full text of which is hereby incorporated by reference.

BACKGROUND ART Porous structures with cushioning properties (for example, urethane foam) have conventionally been manufactured through a process of foaming by chemical reaction, for example, in mold molding (for example, Patent Document 1).

Japanese Patent Application Publication No. 2016-44292

However, when manufacturing a porous structure through the process of foaming through a chemical reaction as described above, there are problems in that the manufacturing process is time-consuming and labor-intensive, and there is a risk that the desired structure may not be obtained. was there.

Therefore, the inventor of the present invention newly focused on the fact that if a porous structure can be manufactured using a 3D printer, manufacturing will be simplified and the desired structure can be obtained. This led to the present invention.

The present invention provides a porous structure, a method for manufacturing the porous structure, and 3D printing data that can easily produce a porous structure with cushioning properties using a 3D printer. purpose.

The porous structure of the present invention is
A porous structure made of flexible resin or rubber,
The porous structure includes a skeleton portion throughout the porous structure,
The skeleton part is
multiple bones,
a plurality of connecting parts each connecting the ends of the plurality of bone parts;
It is composed of
The skeleton portion has a plurality of first annular portions, each of which is configured in an annular shape from a plurality of the bone portions and a plurality of the joint portions,
Each of the first annular portions defines a first virtual surface by its inner peripheral edge,
At least one said first virtual surface is covered with a membrane.

The method for manufacturing a porous structure of the present invention includes:
The above porous structure is manufactured using a 3D printer.

The 3D printing data of the present invention is
3D printing data read into a control unit of the 3D printer when the modeling unit of the 3D printer performs modeling,
The control section is configured to cause the modeling section to model the above-mentioned porous structure.

According to the present invention, a porous structure, a method for manufacturing a porous structure, and 3D printing data are provided, which allow a porous structure with cushioning properties to be easily manufactured using a 3D printer. be able to.

FIG. 4 is a plan view showing a part of a porous structure according to an embodiment of the present invention when viewed from the direction of arrow C in FIGS. 2 to 4. FIG. FIG. 4 is a side view showing the porous structure of FIG. 1 when viewed from the direction of arrow A in FIGS. 1, 3, and 4. FIG. FIG. 5 is a perspective view showing the porous structure of FIG. 1 when viewed from the direction of arrow D in FIGS. 1, 2, and 4. FIG. FIG. 3 is a perspective view showing the porous structure of FIG. 1 when viewed from the direction of arrow B in FIGS. 2 and 3. FIG. FIG. 5 is a perspective view showing a unit part of the porous structure in FIG. 1 when viewed from the direction of arrow D in FIGS. 1, 2, and 4. FIG. 6 is a perspective view showing an enlarged view of a part of the unit part of the porous structure of FIG. 5. FIG. FIG. 6 is a perspective view showing the unit part of the porous structure in FIG. 5 when viewed from the direction of arrow E in FIG. 5. FIG. This is the same drawing as FIG. 7, and only some symbols and broken lines and chain lines are different from FIG. FIG. 6 is a perspective view showing the unit part of the porous structure in FIG. 5 when viewed from the direction of arrow F in FIG. 5; This is the same drawing as FIG. 9, and only some symbols and broken lines and chain lines are different from FIG. 11(a) is a perspective view showing the bone portion of the porous structure of FIG. 1 in a state where no external force is applied, and FIG. 11(b) is a perspective view showing the bone part of the porous structure in FIG. It is a perspective view showing the bone part of. It is a drawing corresponding to FIG. 8, and is a drawing for explaining a porous structure according to a first modification of the present invention. It is a drawing corresponding to FIG. 8, and is a drawing for explaining a porous structure according to a second modification of the present invention. 9 is a drawing corresponding to FIG. 8 and showing a unit part different from that shown in FIG. 5, which is provided in the porous structure of FIG. 1. FIG. 1 is a perspective view showing a vehicle seat pad including a porous structure according to an embodiment of the present invention. 1 is a drawing for explaining a method for manufacturing a porous structure according to an embodiment of the present invention. It is a drawing for explaining the manufacturing method of the porous structure based on the modified example of this invention. FIG. 18(a) is a cross-sectional view showing an example of a cushion pad portion of a vehicle seat pad made of a porous structure according to an embodiment of the present invention, taken along line GG in FIG. , FIG. 18(b) is a cross-sectional view showing an example of the back pad portion of a vehicle seat pad made of a porous structure according to an embodiment of the present invention, taken along line HH in FIG. It is.

The porous structure of the present invention and the porous structure produced using the porous structure production method or 3D modeling data of the present invention are suitable for use in cushioning materials, and for seating. It is more suitable for use in cushioning materials (seat pads, etc.), and even more suitable for use in vehicle seat pads.

EMBODIMENT OF THE INVENTION Hereinafter, embodiments of a porous structure, a method for manufacturing a porous structure, and 3D modeling data according to the present invention will be described by way of example with reference to the drawings.
Common components in each figure are given the same reference numerals.
In addition, in FIGS. 1 to 10 and 12 to 14, the orientation of the XYZ orthogonal coordinate system fixed to the porous structure in each example is shown to make it easier to understand the orientation of the porous structure. ing.

First, a porous structure according to an embodiment of the present invention will be described with reference to FIGS. 1 to 11 and 14.
In FIGS. 1 to 4, a portion of the porous structure 1 according to the present embodiment, which has been cut into a rectangular parallelepiped, is viewed from different angles. FIG. 1 is a plan view of one surface of the relevant portion of the porous structure 1, that is, the relevant portion of the porous structure 1 is viewed in the direction of arrow C (−X direction). 2 is a plan view of the right side surface in FIG. 1 of the portion of the porous structure 1, that is, the portion of the porous structure 1 is Viewed from the direction of the arrow (-Y direction). FIG. 3 shows the same surface of the porous structure 1 as shown in FIG. 1 viewed diagonally from above. I'm looking at it from the direction of. FIG. 4 shows the surface of the part of the porous structure 1 opposite to that shown in FIGS. 1 and 3 viewed diagonally from above. Viewing from the direction of the B arrow.
In the following, for convenience of explanation, the first and second modified examples shown in FIGS. 12 and 13, respectively, and the unillustrated modified example will also be described.

The porous structure 1 of each example described in this specification is modeled using a 3D printer. By manufacturing a porous structure using a 3D printer, manufacturing becomes easier and the desired structure can be obtained compared to the conventional process of foaming through a chemical reaction. Furthermore, since the degree of freedom in designing the cell structure of the porous structure can be greatly expanded, it is also possible to meet a wider range of required characteristics. Further, with future technological advances in 3D printers, it is expected that manufacturing using 3D printers will become possible in the future in a shorter time and at lower cost.
The porous structure 1 is made of flexible resin or rubber. More specifically, the porous structure 1 includes a skeleton part 2 that forms the skeleton of the porous structure 1, and a large number of cell pores C defined by the skeleton part 2. The skeleton 2 exists throughout the porous structure 1 and is made of flexible resin or rubber. In this example, the portions of the porous structure 1 other than the skeleton portion 2 are voids.
Here, "flexible resin" refers to a resin that can be deformed when external force is applied. For example, elastomer-based resins are preferred, polyurethane is more preferred, and soft polyurethane is more preferred. It is even more suitable. As the rubber, natural rubber or synthetic rubber can be mentioned. Since the porous structure 1 is made of flexible resin or rubber, it can be compressed and deformed in response to the application and release of external force, and can have cushioning properties.
Note that from the viewpoint of ease of manufacturing with a 3D printer, it is more preferable for the porous structure 1 to be made of flexible resin than to be made of rubber. .

The porous structure 1 shown in each figure has a structure in which a plurality of cubic unit parts U are integrally connected in each of the X, Y, and Z directions. In the example shown in FIGS. 1 to 10, the portions shown in FIGS. 1 to 4 of the porous structure 1 have a total of three pieces arranged in the Z direction, three pieces in the Y direction, and two pieces in the X direction. It consists of 18 unit parts U. In the examples shown in each figure, the configuration, dimensions, and orientation of the unit parts U constituting the porous structure 1 are the same. For convenience, in FIGS. 1 to 4, only one unit U is colored in a darker gray color than the other units U, and in FIGS. 1 and 2, it is also colored in a darker gray color. The outer edge of the unit U is shown by a dotted line.
As in the examples shown in FIGS. 1 to 10, when the outer edge (outer contour) of each unit U of the porous structure 1 forms a cube, it is possible to obtain equal mechanical properties in each of the X, Y, and Z directions.
Note that the outer edge (outer contour) of the unit portion U may be a rectangular parallelepiped other than a cube, or may have another shape. Further, the configuration and/or dimensions of each unit U constituting the porous structure 1 may not be completely the same, and may differ slightly from each other. When the outer edge (outer contour) of each unit U of the porous structure 1 forms a rectangular parallelepiped other than a cube, it becomes possible to obtain intentional anisotropy as a function of the porous structure 1. For example, when applying the porous structure 1 to a seat pad for a vehicle, by making the outer edge (outer contour) of each unit part U into a rectangular parallelepiped other than a cube, it is soft in the Z direction (the direction in which a person sits). This makes it possible to improve ride comfort.

5 to 10 individually show one unit U in the porous structure 1 of FIGS. 1 to 4. In FIG. 5, the unit part U is viewed from approximately the same direction as in FIG. 3, that is, the unit part U is viewed from the direction of arrow D in FIGS. 1, 2, and 4. FIG. 6 shows an enlarged view of a part of FIG. 7 and 8 are the same drawings, and the same side of the unit U as in FIG. 5 is viewed from below, that is, the unit U is viewed from the direction of arrow E in FIGS. 3 and 5. I'm watching. 7 and 8 differ only in that different dashed lines and chain lines are used for ease of viewing the drawings. 9 and 10 are the same drawings, and show a portion of the unit U on the opposite side to that in FIG. 5 viewed from above, that is, the unit U is viewed from the direction of the arrow F in FIGS. I'm watching. 9 and 10 differ only in that different broken lines and chain lines are used for ease of viewing the drawings. For reference, the A arrow, B arrow, and C arrow in FIGS. 1 to 4 are also shown in FIGS. 5 and 7 to 10.

As shown in FIGS. 1 to 10 and 12 to 14, the skeleton part 2 of the porous structure 1 is composed of a plurality of bone parts 2B and a plurality of joint parts 2J. The whole is constructed in one piece. In the examples shown in the figures, each bone portion 2B has a columnar shape, and in this example, each bone portion 2B extends linearly. Each joint 2J is a location where the end portions 2Be of a plurality of (in the illustrated example, two to six) bone portions 2B in the extending direction that extend in different directions are adjacent to each other. The end portions 2Be are joined together.
In FIG. 6, FIG. 7, FIG. 9, etc., a skeleton line O of the skeleton portion 2 is shown in a part of the porous structure 1. The skeleton line O of the skeleton part 2 consists of the skeleton line O of each bone part 2B and the skeleton line O of each joint part 2J. The skeletal line O of the bone portion 2B is the central axis of the bone portion 2B, and is composed of the central axis of a constant bone portion 2B1 and the central axis of a bone change portion 2B2, which will be described later. The skeletal line O of the joint 2J is an extension line portion formed by smoothly extending the central axes of the bone parts 2B connected to the joint 2J into the joint 2J and connecting them to each other. The central axis of the bone portion 2B is a line connecting the center of gravity of the shape of the bone portion 2B in a cross section perpendicular to the extending direction of the bone portion 2B at each point in the extending direction of the bone portion 2B. .
The direction in which the bone portion 2B extends is the direction in which the skeletal line O of the bone portion 2B (the portion of the skeletal line O that corresponds to the bone portion 2B; the same applies hereinafter).
Since the porous structure 1 is provided with the skeleton 2 throughout its entirety, it is capable of compressing and restoring deformation in response to the application and release of external force while ensuring breathability, so that it has the characteristics as a cushioning material. Become good. Moreover, the structure of the porous structure 1 becomes simple, making it easier to model with a 3D printer.
In addition, some or all of the bone parts 2B constituting the skeleton part 2 may extend while being curved. In this case, some or all of the bone portions 2B are curved, which prevents sudden changes in shape of the bone portions 2B and, by extension, the porous structure 1, and suppresses local buckling when a load is input. be able to.
In addition, in each drawing of FIGS. 1 to 10 and 12 to 14, each surface of the skeleton 2 is flat, and the edge portions (side portions) where a pair of adjacent surfaces butt each other are angular. There is. However, in each example described in this specification, a part or all of each surface of the skeleton portion 2 may be non-flat (for example, curved). Further, in each example described in this specification, each edge portion of the skeleton portion 2 may be smoothly curved.

In the examples shown in the figures, the bone parts 2B constituting the skeleton part 2 each have substantially the same shape and dimensions (length, cross-sectional area, width, etc.). However, the shapes and/or dimensions (length, cross-sectional area, width, etc.) of each bone part 2B constituting the skeleton part 2 may not be the same, and are not limited to the examples shown in each figure. The shape and/or dimensions (length, cross-sectional area, width, etc.) of the bone portion 2B may be different from those of the other bone portions 2B. In this case, by making the shape and/or dimensions (length, cross-sectional area, width, etc.) of the bone part 2B of a specific part of the skeleton part 2 different from that of other parts, intentionally different mechanical properties can be obtained. Obtainable. For example, when the porous structure 1 is applied to a seat pad for a vehicle, as in the example shown in FIG. However, the portion 12 constituting the side pad portion 312 can be made hard to provide a holding feeling.
FIG. 11 shows the bone portion 2B of each example in FIGS. 1 to 10, 13, and 14 alone. FIG. 11(a) shows a natural state in which no external force is applied to the bone portion 2B, and FIG. 11(b) shows a state in which an external force is applied to the bone portion 2B. FIG. 11 shows the central axis (skeletal line O) of the bone portion 2B.
As shown in FIG. 11(a), in each example of FIGS. 1 to 10, FIG. 13, and FIG. , a pair of bone changing portions 2B2 extending from the constant bone portion 2B1 to the joining portion 2J while gradually changing the cross-sectional area on both sides of the constant bone portion 2B1 in the extending direction. The bone change portion 2B2 extends while gradually changing its cross-sectional area. In each example, each bone change portion 2B2 extends from the constant bone portion 2B1 to the joining portion 2J while gradually increasing the cross-sectional area. Note that the same effect is not limited to these examples, and even if only some of the bone portions 2B of the bone portions 2B that constitute the skeleton portion 2 satisfy this configuration, the same effect can be obtained. Further, some or all of the bone parts 2B constituting the skeleton part 2 have a bone change part 2B2 only at one end of the constant bone part 2B1, and the constant bone part 2B1 The other end may be directly connected to the connecting portion 2J, and in that case, the same effect can be obtained although there may be a difference in degree.
Here, the cross-sectional areas of the constant bone portion 2B1 and the bone change portion 2B2 refer to the cross-sectional areas of the constant bone portion 2B1 and the bone change portion 2B2 in a cross section perpendicular to the skeletal line O, respectively. Moreover, in this specification, "gradual change (increase or decrease)" refers to always smoothly changing (increase or decrease) without becoming constant midway.
In each of the examples shown in FIGS. 1 to 10, FIG. 13, and FIG. Since the cross-sectional area gradually increases from the constant portion 2B1 toward the joining portion 2J, the bone portion 2B becomes thinner toward the constant bone portion 2B1 near the boundary between the constant bone portion 2B1 and the bone change portion 2B2. It has a constricted shape. Therefore, when an external force is applied, the bone portion 2B is likely to undergo buckling deformation at its constricted portion or the intermediate portion of the constant bone portion 2B1, and as a result, the porous structure 1 is likely to be compressively deformed. This provides the same behavior and properties as typical polyurethane foams produced through a chemical reaction foaming process. Moreover, this makes the surface of the porous structure 1 softer to the touch. For example, when the porous structure 1 is used as a cushioning material for sitting (such as a seat pad), it provides a softer feel to the seated person when sitting, especially at the beginning of sitting. Such a soft feel is generally preferred by a wide range of people, and is also preferred by occupants of luxury car seat pads (e.g., occupants sitting in the rear seats when chauffeur-driven people ride in the back seats). It is something that can be done.

In each of the examples shown in FIGS. 1 to 10 and 12 to 14, the bone portion 2B has a constant bone portion 2B1 in at least a portion thereof. As in these examples, when the bone portion 2B has the fixed bone portion 2B1 in at least a portion thereof, the cross-sectional area A1 of the end 2B21 on either side (preferably on both sides) of the bone portion 2B (Fig. 11 The ratio A0/A1 of the cross-sectional area A0 (FIG. 11(a)) of the constant bone portion 2B1 to (a) is as follows:
0.15≦A0/A1≦2.0
It is preferable that the following conditions are met. Thereby, the touch feeling on the surface of the porous structure 1 can be made to have a moderate hardness, not too soft or too hard, as a characteristic of the cushioning material, and especially as a characteristic of the cushioning material for seating. For example, when the porous structure 1 is used as a cushioning material for sitting (seat pad, etc.), it gives the occupant a moderately firm feel when sitting, especially at the beginning of sitting. . The smaller the ratio A0/A1, the softer the touch feeling on the surface of the porous structure 1. If the ratio A0/A1 is less than 0.15, the touch feeling on the surface of the porous structure 1 may become too soft, which may result in unfavorable characteristics of the cushioning material, and it may be difficult to manufacture using a 3D printer. Therefore, it is not preferable in terms of manufacturability. Therefore, it is preferable that the ratio A0/A1 is 0.15 or more. When the ratio A0/A1 is more than 2.0, the touch feeling on the surface of the porous structure 1 becomes too hard, which may lead to unfavorable characteristics of the cushioning material. Therefore, the ratio A0/A1 is preferably 2.0 or less.
Note that the ratio A0/A1 is more preferably 0.5 or more.
More specifically, in each of the examples shown in FIGS. 1 to 10, FIG. 13, and FIG. The changing portions 2B2 each extend from the constant bone portion 2B1 to the joining portion 2J while gradually increasing the cross-sectional area, and the ratio A0/A1 is less than 1.0. Thereby, the touch feeling on the surface of the porous structure 1 can be made relatively soft as a characteristic of the cushioning material, and especially as a characteristic of the cushioning material for seating. Such a soft feel is generally preferred by a wide range of people, and is also preferred by occupants of luxury car seat pads (e.g., occupants sitting in the rear seats when chauffeur-driven people ride in the back seats). It is something that can be done.
Note that each of the bone parts 2B that constitutes the skeleton part 2 may satisfy this configuration, or only some of the bone parts 2B of each bone part 2B that constitutes the skeleton part 2 satisfy this configuration. In either case, similar effects can be obtained, although there may be differences in degree.

In addition, instead of each example of FIGS. 1 to 10, FIG. 13, and FIG. good. In this case, the constant bone portion 2B1 has a larger (thicker) cross-sectional area than the bone change portion 2B2. As a result, when an external force is applied, the fixed bone part 2B1 becomes difficult to deform, and instead, the part that is relatively easy to buckle becomes the bone change part 2B2 (particularly the part on the joint part 2J side), and as a result, the porous structure The body 1 becomes difficult to compress and deform. This makes the surface of the porous structure 1 harder to touch, and provides high hardness mechanical properties. For example, when the porous structure 1 is used as a cushioning material for sitting, it gives a harder feeling to the seated person when sitting, especially at the beginning of sitting. Such behavior cannot be obtained with typical polyurethane foams manufactured through a process of foaming through chemical reactions. Such a configuration can accommodate users who prefer a firmer feel. Such a hard feel is preferred by occupants, for example, in seat pads for sports cars that perform rapid acceleration, deceleration, and diagonal changes.
When the bone change portion 2B2 extends from the constant bone portion 2B1 to the joining portion 2J while gradually decreasing its cross-sectional area, the ratio A0/A1 becomes more than 1.0.
Note that each of the bone parts 2B that constitutes the skeleton part 2 may satisfy this configuration, or only some of the bone parts 2B of each bone part 2B that constitutes the skeleton part 2 satisfy this configuration. In either case, similar effects can be obtained, although there may be differences in degree.

Alternatively, as in a first modified example partially indicated by dotted lines in FIG. 12, the bone portion 2B may consist only of a constant bone portion 2B1 without having a bone change portion 2B2. In this case, the cross-sectional area of the bone portion 2B is constant over its entire length. The touch feeling of the surface of the porous structure 1 when an external force is applied is medium hard. Such a configuration can accommodate users who prefer a medium-hard feel. Furthermore, it can be suitably applied to seat pads of all types of cars, including luxury cars and sports cars.
In this case, the ratio A0/A1 is 1.0.
Note that each of the bone parts 2B that constitutes the skeleton part 2 may satisfy this configuration, or only some of the bone parts 2B of each bone part 2B that constitutes the skeleton part 2 satisfy this configuration. In either case, similar effects can be obtained, although there may be differences in degree.

In each of the examples shown in FIGS. 1 to 10, FIG. 13, and FIG. The cross-sectional area is smaller than that of the changing portion 2B2 and the coupling portion 2J. More specifically, the cross-sectional area of the constant bone portion 2B1 is the cross-sectional area of any part of the bone change portion 2B2 and the connecting portion 2J (excluding the boundary portion between the constant bone portion 2B1 and the bone change portion 2B2). smaller than. That is, the constant bone portion 2B1 is a portion with the smallest (slenderest) cross-sectional area in the skeleton portion 2. As a result, as described above, when an external force is applied, the constant bone portion 2B1 is easily deformed, and in turn, the porous structure 1 is easily compressed and deformed. This makes the surface of the porous structure 1 softer to the touch.
Note that the cross-sectional area of the joint portion 2J refers to the cross-sectional area of a cross section perpendicular to the skeleton line O of the joint portion 2J.
Note that this is not limited to these examples, and only some of the bones 2B constituting the skeleton 2 may satisfy this configuration, and even in that case, although there may be differences in degree, , a similar effect can be obtained.
Further, in some or all of the bone parts 2B constituting the skeleton part 2, when the bone part 2B has a constant bone part 2B1 and a bone change part 2B2, the cross-sectional area of the constant bone part 2B1 is It may be larger than the cross-sectional area of any part of the bone change part 2B2 and the joint part 2J (excluding the boundary part between the constant bone part 2B1 and the bone change part 2B2).

Similarly, in each example of FIGS. 1 to 10, FIG. 13, and FIG. However, the width is smaller than that of the bone change part 2B2 and the joint part 2J. More specifically, the width of the constant bone portion 2B1 is greater than the width of any part of the bone change portion 2B2 and the connecting portion 2J (excluding the boundary between the constant bone portion 2B1 and the bone change portion 2B2). ,small. That is, the constant bone portion 2B1 is the smallest (slender) portion of the skeleton portion 2. This also makes it easier for the constant bone portion 2B1 to deform when an external force is applied, thereby making the surface of the porous structure 1 softer to the touch. Note that in these examples, the ratio A0/A1 is less than 1.0, as described above.
In addition, the widths of the constant bone part 2B1, the bone change part 2B2, and the joining part 2J are measured along the cross section perpendicular to the skeletal line O of the constant bone part 2B1, the bone changing part 2B2, and the joining part 2J, respectively. Refers to the maximum width in the relevant cross section. The skeleton line O of the joint portion 2J is a portion of the skeleton line O that corresponds to the joint portion 2J. For reference, FIG. 11A shows the width W0 of the constant bone portion 2B1 and the width W1 of the bone change portion 2B2.
Note that this is not limited to these examples, and only some of the bones 2B constituting the skeleton 2 may satisfy this configuration, and even in that case, although there may be differences in degree, , a similar effect can be obtained.
Further, in some or all of the bone parts 2B constituting the skeleton part 2, when the bone part 2B has a constant bone part 2B1 and a bone change part 2B2, the width of the constant bone part 2B1 is It may be larger than the width of any part of the changed part 2B2 and the joint part 2J (excluding the boundary part between the constant bone part 2B1 and the bone changed part 2B2). In this case, the ratio A0/A1 will be over 1.0.

In each example described in this specification, when the bone portion 2B has a constant bone portion 2B1 in at least a portion thereof, as in the example in each figure, the structure of the porous structure 1 is simplified, and , from the viewpoint of ease of manufacturing with a 3D printer and from the viewpoint of improving the characteristics as a cushion material (particularly a seat pad, more particularly a vehicle seat pad), the width W0 of the constant bone portion 2B1 (FIG. 11) is preferably 0.05 mm or more, more preferably 0.10 mm or more, and even more preferably 0.20 mm or more. When the width W0 is 0.05 mm or more, it is possible to print with the resolution of a high-performance 3D printer, and when it is 0.10 mm or more, it is possible to print not only with the resolution of a high-performance 3D printer but also with a general-purpose 3D printer.
On the other hand, from the viewpoint of improving the precision of the outer edge (outer contour) shape of the porous structure 1, from the viewpoint of reducing the gap (interval) between the cell holes C, from the viewpoint of reducing the gap (interval) between the cell holes C, from the viewpoint of improving the accuracy of the shape of the outer edge (outer contour) of the porous structure 1, from the viewpoint of reducing the gap (interval) between the cell holes C, and from the viewpoint of reducing the precision of the shape of the outer edge (outer contour) of the porous structure 1, From the viewpoint of improving the characteristics as a pad), the width W0 (FIG. 11) of the constant bone portion 2B1 is preferably 2.0 mm or less.
Note that, as in the example of FIG. 12, when the bone portion 2B consists of only the constant bone portion 2B1, the width W0 of the constant bone portion 2B1 is the same as the width W0 of the bone portion 2B.
Note that it is preferable that each bone portion 2B constituting the skeleton portion 2 satisfies this configuration, but only some of the bone portions 2B of the bone portions 2B constituting the skeleton portion 2 satisfy this configuration. Even in that case, the same effect can be obtained, although there may be a difference in degree.

In each of the examples shown in FIGS. 1 to 10, FIG. 13, and FIG. It has one or more (in this example, three) inclined surfaces 2B23 on the side surfaces, and these inclined surfaces 2B23 are inclined (inclined at less than 90°) with respect to the extending direction of the bone change portion 2B2. At the same time, the width W2 gradually increases from the fixed bone portion 2B1 toward the joint portion 2J.
This also makes it easy for the bone portion 2B to undergo buckling deformation at the constricted portion near the boundary between the constant bone portion 2B1 and the bone change portion 2B2 when an external force is applied, and as a result, the porous structure 1 is compressed. It becomes easier to deform. This makes the surface of the porous structure 1 softer to the touch.
Here, the extending direction of the bone modified portion 2B2 is the extending direction of the central axis (skeletal line O) of the bone modified portion 2B2. Further, the width W2 of the sloped surface 2B23 of the bone modified portion 2B2 refers to the width of the sloped surface 2B23 when measured along a cross section perpendicular to the skeletal line O of the bone modified portion 2B2.
In addition, in the examples of these figures, all of the plurality of inclined surfaces 2B23 included in the bone altered portion 2B2 satisfy this configuration, but some of the plurality of inclined surfaces 2B23 included in the plurality of inclined surfaces 2B23 included in the bone altered portion 2B2 This configuration may be satisfied, and even in that case, the same effect can be obtained, although there may be a difference in degree. In addition, in the examples of these figures, the plurality of inclined surfaces 2B23 of the bone changed part 2B2 are congruent with each other, but the plurality of inclined surfaces 2B23 of the bone changed part 2B2 do not have to be congruent with each other, and are different in shape and shape from each other. /or dimensions may be different. Furthermore, only some of the bone parts 2B of the bone parts 2B constituting the skeleton part 2 may satisfy this configuration, and even in that case, the same effect can be obtained, although there may be differences in degree. .
Further, in some or all of the bone parts 2B constituting the skeleton part 2, when the bone part 2B has a constant bone part 2B1 and a bone change part 2B2, each inclined surface 2B23 of the bone change part 2B2 The width W2 may gradually decrease from the constant bone portion 2B1 toward the joint portion 2J. In this case, the ratio A0/A1 will be over 1.0.

In each example described in this specification, in all or some (preferably all) of the bone parts 2B constituting the skeleton part 2, the bone parts 2B (the bone parts 2B are When the bone constant portion 2B1 and the bone change portion 2B2 are included, the cross-sectional shape of the constant bone portion 2B1 and/or the bone change portion 2B2 is preferably a polygon (preferably a regular polygon) or a circle. For example, in each of the examples shown in FIGS. 1 to 10, FIG. 13, and FIG. ) has a polygonal cross-sectional shape (more specifically, an equilateral triangle).
This simplifies the structure of the porous structure 1, making it easier to model with a 3D printer. In addition, it is easy to reproduce the mechanical properties of general polyurethane foam manufactured through a process of foaming through a chemical reaction. Further, by configuring the bone portion 2B in a columnar shape in this manner, the durability of the porous structure 1 can be improved compared to a case where the bone portion 2B is replaced with a thin membrane-like portion.
Note that the cross-sectional shape of the bone portion 2B, the cross-sectional shape of the constant bone portion 2B1, and the cross-sectional shape of the bone change portion 2B2 are aligned with the central axis (skeletal line O) of the bone portion 2B, constant bone portion 2B1, and bone change portion 2B2, respectively. This is the shape in a vertical cross section.
Note that only some of the bone parts 2B of the bone parts 2B constituting the skeleton part 2 may satisfy this configuration, and even in that case, the same effect can be obtained, although there may be a difference in degree. .
Furthermore, in each example described in this specification, in all or some of the bone parts 2B constituting the skeleton part 2, the bone part 2B (bone part 2B is a constant bone part 2B1 and a bone change part 2B) In the case where the constant bone portion 2B1 and/or the bone change portion 2B2) have the constant bone portion 2B1 and/or the bone change portion 2B2), the cross-sectional shape of each may be a polygon other than an equilateral triangle (a triangle other than an equilateral triangle, a quadrilateral, etc.), or a circular ( It may be a perfect circle, an ellipse, etc.), and the same effect can be obtained even in that case. Further, when the bone portion 2B has a constant bone portion 2B1 and a bone change portion 2B2, the constant bone portion 2B1 and the bone change portion 2B2 may have the same or different cross-sectional shapes.

In each example described in this specification, some or all of the bone parts 2B constituting the skeleton part 2 have a cross-sectional area that gradually changes without having a constant bone part 2B1. It may have only the extending bone change portion 2B2. In this case, the bone change portion 2B2 may have a cross-sectional area that gradually increases or decreases from one side to the other side in the extending direction of the bone portion 2B over the entire bone portion 2B, or A portion where the cross-sectional area gradually increases from one side to the other side in the extending direction of the bone portion 2B, and a portion where the cross-sectional area gradually decreases from one side to the other side in the extending direction of the bone portion 2B. may include one or more of each.

In each example described in this specification, the proportion (VB×100/VS [%]) of the volume VB occupied by the skeleton part 2 in the volume VS of the porous structure 1 is 3 to 10%, suitable. With this configuration, the reaction force generated in the porous structure 1 when an external force is applied to the porous structure 1, and the hardness of the porous structure 1, can be used as a cushioning material, especially as a cushioning material for seating. It can be made into a good product (such as a seat pad), particularly as a seat pad for a vehicle.
Here, the "volume VS of the porous structure 1" refers to the entire internal space surrounded by the outer edge (outer contour) of the porous structure 1 (the volume occupied by the skeleton 2 and the volume occupied by the membrane 3, which will be described later). volume and the volume occupied by voids).
When considering that the materials constituting the porous structure 1 are the same, the higher the ratio of the volume VB occupied by the skeleton portion 2 to the volume VS of the porous structure 1, the harder the porous structure 1 becomes. Furthermore, the lower the proportion VB of the volume occupied by the skeleton portion 2 in the volume VS of the porous structure 1, the softer the porous structure 1 becomes.
The reaction force generated in the porous structure 1 when an external force is applied to the porous structure 1, and the hardness of the porous structure 1, can be used as a cushioning material, especially as a cushioning material for seating. From the viewpoint of making the porous structure 1 more suitable, the ratio of the volume VB occupied by the skeleton portion 2 to the volume VS of the porous structure 1 is 4 to 8%.
Note that any method may be used to adjust the proportion of the volume VB occupied by the skeleton part 2 in the volume VS of the porous structure 1, but for example, each unit part U of the porous structure 1 The thickness (cross-sectional area) of some or all of the bone parts 2B that make up the skeleton part 2, and/or the size of some or all of the joint parts J that make up the skeleton part 2, without changing the dimensions of (cross-sectional area).
As an example, in the second modified example shown in FIG. By increasing the size (cross-sectional area) of the porous structure 1 shown by the solid line (example in FIG. 8), the proportion of the volume VB occupied by the skeleton part 2 in the volume VS of the porous structure 1 can be increased. is increasing.
When the porous structure 1 is used for a vehicle seat pad, the 25% hardness of the porous structure 1 is preferably 60 to 500N, more preferably 100 to 450N. Here, the 25% hardness (N) of the porous structure 1 is determined by compressing the porous structure by 25% using an Instron compression tester in an environment of 23°C and 50% relative humidity. It is assumed that this is a measured value obtained by measuring the required load (N).

In each example shown in FIGS. 1 to 14, the skeleton part 2 has a plurality of first cell partition parts 21 (as many as the first cell holes C1) that partition the first cell holes C1 therein.
In the example in each figure, each first cell section 21 has a plurality (specifically, 14) of first annular parts 211. Each first annular portion 211 is configured in an annular shape. The plurality of first annular portions 211 of the first cell division portion 21 each partition a flat first virtual surface V1 by the respective annular inner circumferential edge portions 2111. The first virtual surface V1 is a virtual closed plane whose outer edge is defined by the inner peripheral edge 2111 of the first annular portion 211. The plurality of first annular parts 211 constituting the first cell division part 21 are connected to each other so that the first virtual planes V1 divided by the respective inner circumferential edges 2111 do not intersect with each other.
The first cell hole C1 is partitioned by a plurality of first annular parts 211 constituting the first cell partition part 21 and a plurality of first virtual surfaces V1 defined by the plurality of first annular parts 211, respectively. There is. Roughly speaking, the first annular portion 211 is a part that partitions the sides of the three-dimensional shape formed by the first cell hole C1, and the first virtual surface V1 is a constituent surface of the three-dimensional shape formed by the first cell hole C1. This is the part that separates the
With such a configuration, the behavior of compression and restoring deformation of the porous structure 1 in response to the addition and release of external force becomes better as a cushioning material, especially as a cushioning material for seating (seat pad, etc.) . That is, the properties of the porous structure 1 as a cushioning material can be improved.

As shown in the examples in the figures, each first annular portion 211 of the first cell division portion 21 has a plurality of bone portions 2B and a plurality of connections that connect end portions 2Be of the plurality of bone portions 2B to each other. It is preferable that it is composed of a portion 2J. With such a configuration, the characteristics of the porous structure 1 as a cushioning material can be improved.

As in the example in each figure, the connecting portion between the pair of first annular portions 211 that are connected to each other is one bone portion 2B shared by the pair of first annular portions 211, and one bone portion 2B of the bone portion 2B. It is preferable that it is comprised of a pair of coupling parts 2J on both sides. With such a configuration, the characteristics of the porous structure 1 as a cushioning material can be improved.

In the examples in each figure, the first annular part 211 is connected to a pair of first cell compartments 21 adjacent to the first annular part 211 (that is, a pair of first cell compartments 21 with the first annular part 211 therebetween). 21). In other words, the first annular portion 211 constitutes a part of each of the pair of first cell division portions 21 adjacent to the first annular portion 211 .
As a result, if the first annular part 211 is connected to a pair of first cell division parts 21 adjacent to the first annular part 211 (that is, a pair of first cell division parts with the first annular part 211 therebetween), 21), in other words, the pair of first cell division parts 21 are configured independently from each other, and the respective first annular parts 211 are formed adjacent to each other or spaced apart from each other. compared to the case where there is a rib or the like between the first annular portions 211, the gap (spacing) between the first cell holes C1 (and the space between the first cell holes C1) 2) can be made smaller, the characteristics of the porous structure 1 as a cushioning material (particularly a seat pad, more particularly a vehicle seat pad) can be improved. Therefore, the porous structure 1 with cushioning properties can be easily manufactured using a 3D printer.
Note that it is preferable that each first annular portion 211 that constitutes the skeleton portion 2 satisfies this configuration, but only some of the first annular portions 211 of each of the first annular portions 211 that constitute the skeleton portion 2 satisfy this configuration. However, this configuration may be satisfied, and even in that case, the same effect can be obtained, although there may be a difference in degree.
From a similar point of view, in each example described in this specification, the skeleton lines O of a pair of first cell partitions 21 adjacent to each other are the first annular portions shared by the pair of first cell partitions 21. At 211, a match is preferred.

In the examples in each figure, the first virtual surface V1 partitions a part of one first cell hole C1 by a surface on one side of the first virtual surface V1 (the surface of the first virtual surface V1). At the same time, a part of another first cell hole C1 is defined by the surface on the other side of the first virtual surface V1 (the back surface of the first virtual surface V1). In other words, the first virtual surface V1 partitions a portion of the separate first cell holes C1 by its front and back surfaces. In other words, the first virtual surface V1 is formed by a pair of first cell holes C1 adjacent to the first virtual surface V1 (that is, a pair of first cell holes C1 with the first virtual surface V1 in between). shared.
As a result, if the first virtual surface V1 is a pair of first cell holes C1 adjacent to the first virtual surface V1 (that is, a pair of first cell holes C1 with the first virtual surface V1 in between) In other words, compared to the case where the first virtual surfaces V1 of the pair of first cell holes C1 are located apart from each other, the gap (interval) between the first cell holes C1 is Since it can be made smaller, the properties of the porous structure 1 as a cushioning material can be improved.
Note that it is preferable that each first virtual surface V1 forming the skeleton part 2 satisfies this configuration, but only some of the first virtual surfaces V1 among the first virtual surfaces V1 forming the skeleton part 2 However, this configuration may be satisfied, and even in that case, the same effect can be obtained, although there may be a difference in degree.

In each example described in this specification, as in the example in each figure, the skeleton line O of the first annular portion 211 shared by a pair of mutually adjacent first cell partition portions 21 is It is preferable that it is continuous with each of the skeleton lines O of the portions of the cell division portion 21 adjacent to the shared first annular portion 211 (see FIGS. 1, 7, etc.).
This improves the properties of the porous structure as a cushioning material.
From a similar point of view, in each example described in this specification, as in the example in each figure, the skeleton lines O of a pair of mutually adjacent first cell partitions 21 are It is preferable that the first annular portion 211 shared by the first annular portions 21 and 21 coincide with each other.
Further, from the same viewpoint, in each example described in this specification, as in the example in each figure, bones forming the first annular portion 211 shared by a pair of mutually adjacent first cell division portions 21 are used. The cross-sectional area of the portion 2B (for example, the cross-sectional area of the constant bone portion 2B1) is the cross-sectional area of the bone portion 2B that constitutes the portion adjacent to the shared first annular portion 211 of the pair of first cell partition portions 21. It is suitable that each of the areas (for example, the cross-sectional area of the constant bone portion 2B1) is the same.
Note that it is preferable that all of the first annular portions 211 shared by a pair of mutually adjacent first cell division portions 21 in the skeleton portion 2 satisfy this configuration; Only some of the first annular parts 211 among the first annular parts 211 shared by the first cell division parts 21 may satisfy this configuration, and even in that case, the same may be true, although there may be differences in degree. The effect of this can be obtained.

In each example described in this specification, as in the example in each figure, the skeleton line O of the connecting portion between the pair of first annular parts 211 connected to each other is It is preferable that it is continuous with each of the skeleton lines O of the portions adjacent to the connecting portion (see FIGS. 1 and 7).
This improves the properties of the porous structure as a cushioning material.
From the same point of view, in each example described in this specification, the skeleton lines O of a pair of first annular parts 211 connected to each other are It is preferable that the connecting parts match.
Further, from the same viewpoint, in each example described in this specification, as in the example in each figure, the bone portion 2B that constitutes the connecting portion between the pair of first annular portions 211 that are adjacent to each other and connected to each other. The cross-sectional area (for example, the cross-sectional area of the constant bone portion 2B1) is different from the cross-sectional area of the bone portion 2B that constitutes the portion adjacent to the connecting portion of the pair of first annular portions 211 (for example, the cross-sectional area of the constant bone portion 2B1). (area) are preferably the same.
Note that it is preferable that all the connecting parts between the pair of first annular parts 211 connected to each other in the skeleton part 2 satisfy this configuration; Only some of the connecting portions between the connecting portions 211 may satisfy this configuration, and even in that case, the same effect can be obtained, although there may be a difference in degree.

In each of the examples in FIGS. 1 to 10 and 12 to 13, each first virtual surface V1 is not covered with a film and is open, that is, forms an opening. Therefore, the cell holes C are communicated with each other through the first virtual surface V1, and ventilation between the cell holes C is made possible. Thereby, the air permeability of the porous structure 1 can be improved, and the porous structure 1 can be easily compressed and deformed in response to the application and release of external force.

In the examples in each figure, each of the plurality (14 in the figure) of the first annular parts 211 constituting the first cell section 21 is connected to one or more (six in the figure) of the first annular parts 211. It includes a small annular portion 211S and one or more (eight in the illustrated example) first large annular portions 211L. Each first small annular portion 211S defines a flat first small virtual surface V1S by its annular inner peripheral edge 2111. Each of the first large annular portions 211L defines a first large imaginary surface V1L that is flat and has a larger area than the first small imaginary surface V1S by its annular inner peripheral edge 2111. The first small virtual surface V1S and the first large virtual surface V1L are each virtual closed planes.
1, FIG. 7, FIG. 9, etc., a part of the skeleton line O of the part of the skeleton part 2 that constitutes the first cell division part 21 is shown. As can be seen from these drawings, in the examples in each figure, the skeleton line O of the first macrocyclic portion 211L forms a regular hexagon, and accordingly, the first large imaginary surface V1L also has a substantially regular hexagonal shape. is doing. In addition, in the examples in each figure, the skeleton line O of the first small annular portion 211S forms a regular quadrilateral (square), and accordingly, the first small virtual surface V1S also forms a substantially regular quadrilateral. There is. In this way, in the examples in each figure, the first small virtual surface V1S and the first large virtual surface V1L differ not only in area but also in shape.
Each of the first large annular portions 211L includes a plurality of (in the example shown in each figure, six) bone portions 2B and a plurality of (each of the plurality of In the illustrated example, it is composed of six (6) coupling portions 2J. Each of the first small annular portions 211S includes a plurality of (four in each figure) bone parts 2B and a plurality (in each figure, four) of bone parts 2B that connect the ends 2Be of these plurality of bone parts 2B. , four) coupling parts 2J.
In the examples shown in each figure, the skeleton lines O of the plurality of first cell division parts 21 constituting the skeleton part 2 each form a Kelvin tetradecahedron (truncated octahedron). The Kelvin tetradecahedron (truncated octahedron) is a polyhedron composed of six regular quadrilateral constituent faces and eight regular hexagonal constituent faces. Accordingly, the first cell hole C1 defined by each first cell partition portion 21 also has a substantially Kelvin tetradecahedron shape. In each example of FIGS. 1 to 14, each bone portion 2B has not only a constant bone portion 2B1 but also bone change portions 2B2 on both sides thereof. Therefore, the shape of the first cell hole C1 can be calculated mathematically. It does not form a complete Kelvin tetradecahedron. The skeleton lines O of the plurality of first cell division parts 21 constituting the skeleton part 2 are connected to each other so as to fill the space. That is, there is no gap between the skeleton lines O of the plurality of first cell partitions 21.

In this way, in the examples in each figure, the skeleton lines O of the plurality of first cell division parts 21 constituting the skeleton part 2 each form a polyhedron (in the example in each figure, a Kelvin tetradecahedron). , since the first cell pores C1 form a substantially polyhedron (in the examples in each figure, a substantially Kelvin tetradecahedron), the gaps (intervals) between the cell pores C constituting the porous structure 1 can be made smaller. This makes it possible to form more cell pores C inside the porous structure 1. Furthermore, this allows the porous structure 1 to behave better in compression and restoring deformation in response to the application and release of external forces as a cushioning material, particularly as a cushioning material for seating. Note that the gap (interval) between the cell holes C corresponds to the fleshy portions of the skeleton portion 2 (bone portions 2B and joint portions 2J) that partition the cell holes C.
In addition, in the examples shown in each figure, the skeleton lines O of the plurality of first cell division parts 21 constituting the skeleton part 2 are connected to each other so as to fill the space, so that the first cells constituting the porous structure 1 It becomes possible to further reduce the gap (interval) between the holes C1. Therefore, the properties of the porous structure as a cushioning material can be improved.

The polyhedron formed by the skeleton line O of the first cell division part 21 (and the substantially polyhedron formed by the first cell hole C1) is not limited to the examples shown in each figure, but any arbitrary one can be used.
For example, the polyhedron formed by the skeleton lines O of the plurality of first cell division parts 21 constituting the skeleton part 2 (and the substantially polyhedron formed by the first cell holes C1) is one that can fill a space (can be arranged without any gaps). It is preferable that Thereby, the skeleton lines O of the plurality of first cell sections 21 constituting the skeleton section 2 can be connected to each other so as to fill the space, so that the properties of the porous structure as a cushioning material can be improved. . In this case, the polyhedron formed by the skeleton lines O of the plurality of first cell division parts 21 constituting the skeleton part 2 (and the approximate polyhedron formed by the first cell hole C1) is one type of polyhedron as in the example in each figure. It may contain only one polyhedron, or it may contain multiple types of polyhedrons. Here, regarding polyhedra, "type" refers to the shape (number and shape of constituent faces), and specifically, for two polyhedra with different shapes (number and shape of constituent faces), there are two types. This means that two polyhedra that have the same shape and differ only in size are treated as the same type of polyhedron. In the case where the polyhedron formed by the skeleton lines O of the plurality of first cell division parts 21 constituting the skeleton part 2 can fill a space and includes only one type of polyhedron, examples of the polyhedron include the Kelvin tetradecahedron, Examples include a regular triangular prism, a regular hexagonal prism, a cube, a rectangular parallelepiped, and a rhombic dodecahedron. In addition, when the shape of the skeleton line O of the first cell division part 21 is a Kelvin tetradecahedron (truncated octahedron) as in the example in each figure, compared to other shapes, the process of foaming by chemical reaction is more difficult. It is the easiest to reproduce the characteristics of cushioning materials equivalent to those of general polyurethane foam manufactured through the process. Furthermore, when the shape of the skeleton line O of the first cell division section 21 is a Kelvin tetradecahedron (truncated octahedron), it is possible to obtain equal mechanical properties in each of the X, Y, and Z directions. In the case where the polyhedron formed by the skeleton lines O of the plurality of first cell division parts 21 constituting the skeleton part 2 can fill a space and includes a plurality of types of polyhedra, examples of the polyhedron include a regular tetrahedron, a regular octahedron, and a regular octahedron. , a combination of a regular tetrahedron and a truncated tetrahedron, a combination of a regular octahedron and a truncated hexahedron, etc. Note that these are examples of combinations of two types of polyhedra, but combinations of three or more types of polyhedra are also possible.
Further, the polyhedron formed by the skeleton lines O of the plurality of first cell division parts 21 constituting the skeleton part 2 (and the substantially polyhedron formed by the first cell holes C1) may be, for example, any regular polyhedron (all faces are congruent). A regular polyhedron (a convex polyhedron with the same number of tangent faces at all vertices), a semiregular polyhedron (all faces are regular polygons, and all vertex shapes are congruent (types and order of regular polygons that gather at the vertices) Among convex polyhedra (with the same polyhedron), other than regular polyhedrons), prisms, pyramids, etc. are possible.
In addition, the skeleton line O of a part or all of the first cell division parts 21 of the plurality of first cell division parts 21 constituting the skeleton part 2 may have a three-dimensional shape other than a polyhedron (for example, a sphere, an ellipsoid, a cylinder, etc.). etc.). Furthermore, some or all of the first cell holes C1 of the plurality of first cell holes C1 constituting the skeleton portion 2 may have a substantially three-dimensional shape other than a substantially polyhedron (for example, a substantially spherical shape, a substantially ellipsoid shape, a substantially cylindrical shape, etc.). ).

In each example described in this specification, as in the example in each figure, a plurality of first annular parts 211 constituting the first cell partition part 21 have a first small annular part 211S and a first small annular part 211S of different sizes. It is preferable that the large annular portion 211L is included. Thereby, the gap (interval) between the first cell holes C1 constituting the porous structure 1 can be made smaller, and the characteristics of the porous structure 1 as a cushioning material can be improved. In addition, as in the example in each figure, when the shapes of the first small annular part 211S and the first large annular part 211L are different, the gap (interval) between the first cell holes C1 constituting the porous structure 1 is It becomes possible to further reduce the size, and the properties of the porous structure 1 as a cushioning material can be improved.
However, the plurality of first annular portions 211 constituting the first cell section 21 may have the same size and/or shape (type). Even when the first annular portions 211 constituting the first cell section 21 have the same size and shape, it is possible to obtain the same mechanical properties in the X, Y, and Z directions.

In each example described in this specification, as in the example in each figure, some or all (in the example in each figure, all) of the first annular parts 211 constituting the porous structure 1 are It is preferable that the skeleton line O of one annular portion 211 has a polygonal shape (regular hexagonal and regular quadrangular in the examples shown in each figure). Similarly, it is preferable that some or all (in the examples in the figures, all) of the first virtual surfaces V1 constituting the porous structure 1 have a substantially polygonal shape. It is. Thereby, it becomes possible to further reduce the distance between the first cell holes C1 constituting the porous structure 1. Moreover, the behavior of compression and restoring deformation of the porous structure 1 in response to the application and release of an external force becomes better as a cushioning material, particularly as a cushioning material for seating. Furthermore, since the shape of the first annular portion 211 (and thus the shape of the first virtual surface V1) is simplified, it is possible to improve manufacturability and ease of adjusting characteristics. Note that it is preferable that each of the first annular portions 211 (as a result, the first virtual surface V1) constituting the porous structure 1 satisfies this configuration; 211 (and the first virtual surface V1) satisfies this configuration, the same effect can be obtained although there may be a difference in degree. is obtained.
In addition, among each of the first annular parts 211 (and by extension, the first imaginary surface V1) constituting the porous structure 1, the skeleton line O of at least one of the first annular parts 211 (and by extension, the first imaginary surface V1) is It may be any polygonal shape other than the regular hexagon or regular quadrilateral as shown in the example, or a planar shape other than the polygonal shape (for example, a circle (perfect circle, ellipse, etc.)). If the shape of the skeleton line O of the first annular portion 211 (and thus the first virtual surface V1) is a circle (perfect circle, ellipse, etc.), the skeleton line O of the first annular portion 211 (and thus the first virtual surface V1) Since the shape is simple, manufacturability and ease of adjusting properties can be improved, and more homogeneous mechanical properties can be obtained. For example, if the shape of the skeleton line O (and by extension, the first virtual surface V1) of the first annular portion 211 is an ellipse (horizontally long ellipse) that is long in the direction substantially perpendicular to the direction in which the load is applied, the load is applied. The first annular portion 211 that partitions the first virtual surface V1 and, by extension, the porous structure 1 are more responsive to load input than the case where the ellipse is long in the direction substantially parallel to the direction (vertically elongated ellipse). On the other hand, it becomes easier to deform (become softer).

In each example described in this specification, as in the example in each figure, at least one (three in the example in each figure) bone part of the first large annular part 211L of one first cell compartment 21 is 2B is preferably shared by the first small annular portion 211S of another first cell section 21 adjacent to the first cell section 21. Thereby, the characteristics of the porous structure 1 as a cushioning material can be improved.

In each example described in this specification, as in the example in each figure, the first cell hole C1 includes a plurality of first annular portions 211 constituting the first cell partition portion 21 and a plurality of first annular portions 211 constituting the first cell partition portion 21. The plurality of first annular parts 211 constituting the first cell partitioning part 21 are partitioned by the respective inner peripheral side edges 2111. It is preferable that the first virtual surfaces V1 are connected to each other so as not to intersect with each other. Thereby, the characteristics of the porous structure 1 as a cushioning material can be improved.

In each of the examples shown in FIGS. 1 to 10 and 12 to 14, the skeleton part 2 has a plurality of second cell division parts 22 that partition the second cell holes C2 inside (as many as the number of second cell holes C2). have.
As shown in FIGS. 1, 2, and 5 to 10 (particularly FIG. 6), each second cell section 22 includes a plurality of (two in the examples shown in these figures) second annular portions 222. have. Each second annular portion 222 is configured in an annular shape. The plurality of second annular portions 222 of the second cell division portion 22 each partition a flat second virtual surface V2 by the respective annular inner peripheral edge portions 2221. The second virtual surface V2 is a virtual closed plane whose outer edge is defined by the inner peripheral edge 2221 of the second annular portion 222. The second annular parts 222 constituting the second cell division part 22 are connected to each other so that the second virtual planes V2 defined by the respective inner circumferential edges 2221 intersect with each other (in this example, they intersect at right angles). There is.
The second cell hole C2 is partitioned by the respective inner peripheral side edges 2221 of each second annular part constituting the second cell partition section 22 and a virtual plane connecting these inner peripheral side edges 2221. has been done.
With such a configuration, the behavior of compression and restoring deformation of the porous structure 1 in response to the addition and release of external force becomes better as a cushioning material, especially as a cushioning material for seating (seat pad, etc.) . That is, the properties of the porous structure 1 as a cushioning material can be improved.

FIG. 6 shows a skeleton line O of a portion of the unit U that constitutes the second cell section 22. As shown in FIG. As can be seen from FIG. 6, in each of the examples of FIGS. 1 to 10 and 12 to 14, each of the second annular portions 222 constituting the second cell section 22 has a skeleton line O that is a regular quadrangle. Accordingly, the second virtual surface V2 also has a substantially regular quadrangular shape.
In each of the examples shown in FIGS. 1 to 10 and 12 to 14, the skeleton lines O of the plurality of second cell division parts 22 forming the skeleton part 2 each form a regular octahedron. A regular octahedron is a polyhedron made up of eight regular triangular faces. However, in these examples, the skeleton line O of the second cell section 22 constitutes only some of the sides of the polyhedron (regular octahedron) formed by the skeleton line O. Accordingly, the second cell hole C2 defined by each second cell partition portion 22 also has a substantially regular octahedron shape. In each of the examples shown in FIGS. 1 to 10 and 12 to 14, each bone portion 2B has not only a constant bone portion 2B1 but also bone change portions 2B2 on both sides thereof. The shape of does not form a mathematical (perfect) regular octad.
In each example of FIGS. 1 to 10 and 12 to 14, as shown in FIGS. 4 and 10, a portion of the second cell hole C2 is adjacent to the second cell hole C2 (i.e., The second cell hole C2 is sandwiched between the pair of first cell holes C1, that is, the pair of first cell holes C1 and second cell hole C2 partially overlap. There is. As a result, compared to the case where the first cell pores C1 and the second cell pores C2 do not overlap with each other, the total number of cell pores C constituting the porous structure 1 can be increased, and as a result, the porous The properties of the quality structure 1 as a cushioning material can be improved. However, the first cell hole C1 and the second cell hole C2 may be arranged so as not to overlap with each other.

When the porous structure 1 has the second cell division part 22 as in the examples of FIGS. 1 to 10 and 12 to 14, each of the second annular parts 222 has a plurality of In the example, it is composed of four (4) bone parts 2B and a plurality of (four in the examples in these figures) connecting parts 2J that connect the ends 2Be of these plurality of bone parts 2B. (See FIG. 6), which is preferable. With such a configuration, the characteristics of the porous structure 1 as a cushioning material can be improved.

When the porous structure 1 has the second cell division part 22 as in each example of FIGS. 1 to 10 and FIGS. It is preferable that the connecting portion is composed of two connecting portions 2J that are shared by each second annular portion 222. With such a configuration, the characteristics of the porous structure 1 as a cushioning material can be improved.
Furthermore, in the examples shown in these figures, the shapes and areas of the second virtual surfaces V2 constituting the second cell section 22 are the same.

When the porous structure 1 has the second cell division part 22 as in each example of FIGS. 1 to 10 and 12 to 14, the diameter of the second cell pore C2 is larger than the diameter of the first cell pore C1. It is preferable that the value is also small. This makes it easier to reproduce the characteristics of the cushioning material that are equivalent to those of general polyurethane foam manufactured through a process of foaming through a chemical reaction.
However, the diameter of the second cell hole C2 may be greater than or equal to the diameter of the first cell hole C1.

1 to 10 and 12 to 14, when the porous structure 1 has the second cell division part 22, the polyhedron formed by the skeleton line O of the second cell division part 22 (as a result, The substantially polyhedral shape formed by the second cell hole C2 is not limited to the examples shown in each figure, but any arbitrary shape is possible.
For example, the polyhedron formed by the skeleton lines O of the plurality of second cell partitions 22 constituting the skeleton part 2 is different from the polyhedron formed by the skeleton lines O of the plurality of first cell partitions 21 forming the skeleton part 2, respectively. Preferably, they are of different types. For example, when the skeleton lines O of the plurality of first cell division parts 21 constituting the skeleton part 2 each form a Kelvin tetradecahedron as in the example in each figure, the plurality of second cell division parts constituting the skeleton part 2 It is preferable that each of the 22 skeleton lines O forms a polyhedron other than the Kelvin tetradecahedron (a regular octahedron in the examples of FIGS. 1 to 10 and 12 to 14).
The polyhedron formed by the skeleton lines O of the plurality of second cell division parts 22 constituting the skeleton part 2 (and the substantially polyhedron formed by the second cell holes C2) can be, for example, any regular polyhedron (a regular polyhedron in which all faces are congruent). A polygon, a convex polyhedron with the same number of tangent faces at all vertices), a semiregular polyhedron (all faces are regular polygons, and all vertex shapes are congruent (the types and order of regular polygons that gather at the vertices are the same) ) among convex polyhedrons other than regular polyhedrons), prisms, pyramids, etc.
In addition, the skeleton line O of a part or all of the second cell division parts 22 of the plurality of second cell division parts 22 constituting the skeleton part 2 may have a three-dimensional shape other than a polyhedron (for example, a sphere, an ellipsoid, a cylinder, etc.). etc.). Furthermore, some or all of the second cell holes C2 of the plurality of second cell holes C2 constituting the skeleton portion 2 may have a substantially three-dimensional shape other than a substantially polyhedron (for example, a substantially sphere, a substantially ellipsoid, a substantially cylindrical shape, etc.). ).

In addition, when the porous structure 1 has the second cell division part 22 as in each example of FIGS. 1 to 10 and 12 to 14, each second annular part constituting the second cell division part The shape of the skeleton line O of 222 (and thus the shape of each second virtual surface V2) is not limited to this example, but may be any polygonal shape other than a regular quadrilateral, or a planar shape other than a polygonal shape (for example, a circle ( It may be a perfect circle, ellipse, etc.). If the shape of the skeleton line O of the second annular portion 222 (and thus the second virtual surface V2) is approximately polygonal or circular (such as a perfect circle or an ellipse), the skeleton line O of the second annular portion 222 (and thus the Since the shape of the second virtual surface V2) becomes simple, it is possible to improve manufacturability and ease of adjusting characteristics. For example, if the shape of the skeleton line O (and by extension, the second virtual surface V2) of the second annular portion 222 is an ellipse (horizontally long ellipse) that is long in the direction substantially perpendicular to the direction in which the load is applied, The second annular portion 222 that partitions the second virtual surface V2 and, by extension, the porous structure 1 are more susceptible to load input than the case where the ellipse is long in a direction substantially parallel to the direction in which the load is applied. It becomes easier to deform (become softer).

In each example of FIGS. 1 to 10 and 12 to 14, one of the two second annular parts 222 constituting the second cell partition part 22 is connected to the first annular part 211 (more specifically, , the first small annular portion 211S). However, in these examples, only some of the first small annular portions 211S of the plurality of first small annular portions 211S that constitute the first cell division portion 21 also constitute the second annular portion 222.
In each of the examples shown in FIGS. 1 to 10 and 12 to 14, each second virtual surface V2 is not covered with a film and is open, that is, forms an opening. Therefore, the cell holes C (particularly the first cell hole C1 and the second cell hole C2) are communicated with each other through the second virtual surface V2, and ventilation between the cell holes C is made possible. Thereby, the air permeability of the porous structure 1 can be improved, and the porous structure 1 can be easily compressed and deformed in response to the application and release of external force.

When the porous structure 1 has the second cell section 22 as in the examples of FIGS. 1 to 10 and 12 to 14, each second annular section 222 constituting the second cell section 22 , the second virtual planes V2 defined by the respective inner circumferential edges 2221 are connected to each other so as to intersect (orthogonally in this example), and the second cell hole C2 extends through the second cell partition 22. It is preferable that the second annular portion is divided by the respective inner circumferential edges 2221 of the constituent second annular portions and an imaginary surface that smoothly connects these inner circumferential edges 2221. Thereby, the properties of the porous structure as a cushioning material can be improved.

In each of the examples shown in FIGS. 1 to 10 and 12 to 14, one first cell hole C1 has a total of eight unit parts arranged in each of the X, Y, and Z directions. It is composed of U (FIG. 5, FIG. 7 to FIG. 10). Moreover, one unit part U constitutes a part of each of the plurality of first cell holes C1. On the other hand, two second cell holes C2 are arranged for each unit U.
However, without being limited to these examples, each cell pore C of the porous structure 1 may be composed of an arbitrary number of units U, and each unit U may be composed of an arbitrary number of units U. A number of cell holes C may be configured.

However, the porous structure 1 may have only the first cell section 21 without having the second cell section 22.

In each example described in this specification, the porous structure 1 preferably has at least one (preferably a plurality of) cell pores C having a diameter of 5 mm or more. This makes it easier to manufacture the porous structure 1 using a 3D printer. If the diameter of each cell pore C of the porous structure 1 is less than 5 mm, the structure of the porous structure 1 will become too complicated, resulting in three-dimensional shape data (CAD) representing the three-dimensional shape of the porous structure 1. data, etc.), or 3D printing data generated based on the 3D shape data, which may be difficult to generate on a computer.
Note that, as described above, conventional porous structures having cushioning properties were manufactured through a process of foaming by chemical reaction, and therefore it was not possible to form cell pores C with a diameter of 5 mm or more. However, the inventor of the present invention has newly discovered that even when the porous structure has cell pores C with a diameter of 5 mm or more, the same properties as the conventional cushioning material can be obtained. By making the porous structure have cell pores C having a diameter of 5 mm or more, it becomes easier to manufacture using a 3D printer.
Furthermore, since the porous structure 1 has cell pores C having a diameter of 5 mm or more, the air permeability and deformability of the porous structure 1 can be easily improved.
The larger the diameter of the cell pores C, the easier it is to manufacture the porous structure 1 using a 3D printer, and the easier it is to improve air permeability and ease of deformation. From this point of view, in the porous structure 1, the diameter of at least one (preferably a plurality of) cell pores C is preferably 8 mm or more, and still more preferably 10 mm or more.
On the other hand, if the cell pores C of the porous structure 1 are too large, it becomes difficult to form the outer edge (outer contour) of the porous structure 1 neatly (smoothly). When applied to, for example, there is a risk that the shape accuracy will decrease and the appearance will deteriorate. Further, the properties as a cushioning material may not be sufficiently good. Therefore, from the viewpoint of improving the appearance and properties as a cushioning material, the diameter of each cell pore C of the porous structure 1 is preferably less than 30 mm, more preferably less than 25 mm, and even more preferably less than 20 mm. Good.
Note that the more the porous structure 1 has cell pores C that satisfy the above numerical range, the easier it is to obtain each of the above effects. From this point of view, it is preferable that the diameter of at least each first cell hole C1 among the plurality of cell holes C constituting the porous structure 1 satisfies at least one of the above numerical ranges. Further, it is more preferable that the diameter of each cell pore C constituting the porous structure 1 satisfies at least one of the above numerical ranges.
Note that the diameter of the cell hole C refers to the diameter of the circumscribed sphere of the cell hole C when the cell hole C has a shape different from a strict spherical shape as in the example in each figure.

Furthermore, if the cell pores C of the porous structure 1 are too small, it becomes difficult to manufacture (model) the porous structure 1 using a 3D printer. From the viewpoint of facilitating the manufacture of the porous structure 1 using a 3D printer, the cell pore C having the smallest diameter among the cell pores C constituting the porous structure 1 (FIGS. 1 to 10, In each of the examples shown in FIGS. 12 to 14, the diameter of the second cell hole C2) is preferably 0.05 mm or more, and more preferably 0.10 mm or more. If the diameter of the cell hole C with the smallest diameter (the second cell hole C2 in each example of FIGS. 1 to 10 and 12 to 14) is 0.05 mm or more, the resolution of a high-performance 3D printer is sufficient. If it is 0.10 mm or more, it can be printed not only with a high-performance 3D printer but also with the resolution of a general-purpose 3D printer.

As shown in FIG. 14, in each example described in this specification, the porous structure 1 has at least one of each first virtual surface V1 that constitutes the porous structure 1 covered with the membrane 3. ing. The membrane 3 is made of the same material as the skeleton part 2 and is constructed integrally with the skeleton part 2. The membrane 3 causes the two first cell pores C1 with the first virtual surface V1 in between to become non-communicating with each other, and as a result, the air permeability of the porous structure 1 as a whole decreases. By adjusting the number of first virtual surfaces V1 that constitute the porous structure 1 that are covered with the membrane 3, the air permeability of the porous structure 1 as a whole can be adjusted. Various levels of breathability are achievable. For example, when the porous structure 1 is used as a seat pad for a vehicle, adjusting the ventilation of the porous structure 1 can improve the effectiveness of the air conditioner inside the car, improve the resistance to stuffiness, and improve riding comfort. can be increased. When the porous structure 1 is used as a seat pad for a vehicle, from the viewpoint of increasing the effectiveness of the air conditioner in the car and resistance to stuffiness, as well as improving ride comfort, each first virtual surface constituting the porous structure 1 is It is not preferable that all of V1 be covered with the membrane 3; in other words, at least one (preferably a plurality of) of each first virtual surface V1 constituting the porous structure 1 is covered with the membrane 3. It is preferable that the area is open and not closed.
When the porous structure 1 is used as a vehicle seat pad, the air permeability of the porous structure 1 is 100 to 700 cc from the viewpoint of increasing the effectiveness and stuffiness resistance of the air conditioner in the car, and improving ride comfort. /cm ² /sec is preferred, 150 to 650 cc/cm ² /sec is more preferred, and 200 to 600 cc/cm ² /sec is even more preferred. Here, the air permeability (cc/cm ² /sec) of the porous structure 1 shall be measured in accordance with JIS K 6400-7. Further, when the porous structure 1 is used for a vehicle seat pad, the resonance magnification of the porous structure 1 is preferably 3 times or more and less than 8 times, more preferably 3 times or more and 5 times or less. .
As mentioned above, conventional porous structures were manufactured through a process of foaming through chemical reactions, so it was difficult to form the membranes in the communicating holes that communicated each cell with each other in the desired position and number. It was difficult to do. When manufacturing the porous structure 1 with a 3D printer, as in the example in FIG. It is possible to form the film 3 at the position and number of the film 3.
From a similar point of view, at least one of the first small virtual surfaces V1S constituting the porous structure 1 may be covered with the membrane 3. And/or at least one of the first large virtual surfaces V1L constituting the porous structure 1 may be covered with the membrane 3. Further, the membrane 3 may be provided so as to connect the plurality of second annular parts 222 constituting the second cell division part 22 and cover a part of the second cell hole C2.

As described above, the porous structure of the present invention is suitable for use in cushioning materials, more preferably in cushioning materials for seating (seat pads, etc.), and is suitable for use in vehicle seat pads. It is even more preferable to use
As an example, FIG. 15 shows a vehicle seat pad 300 including the porous structure 1 of the example shown in FIG. The vehicle seat pad 300 in the example of FIG. 15 includes a cushion pad 310 for a seated person to sit on, and a back pad 320 for supporting the back of the seated person. The cushion pad 310 and the back pad 320 can each be constructed from any of the porous structures 1 described above.
In FIG. 15, directions such as "top", "bottom", "left", "right", "front", and "rear" as viewed from the seated person seated on the vehicle seat pad 300 are indicated. There is.
The cushion pad 310 has a main pad part 311 configured to rest on the buttocks and thighs of the seated person, and a pair of side pad parts 322 located on both left and right sides of the main pad part 311.
In the example of FIG. 15, the cushion pad 310 and the back pad 320 are each composed of separate (separate members) porous structures 1. The entire cushion pad 310 is constructed in one piece. Further, the entire back pad 320 is constructed in one piece.
The porous structures 1 that constitute the cushion pad 310 and the back pad 320 are each modeled using a 3D printer.
However, the cushion pad 310 and the back pad 320 may be integrally formed with each other.
Further, in the example of FIG. 15, the back pad 320 is configured separately from the headrest for supporting the head of the seated person, but the back pad 320 may be configured integrally with the headrest.
Moreover, the porous structure 1 may constitute only a part of the vehicle seat pad 300 (cushion pad 310 or back pad 320). In that case, the remaining portion of the vehicle seat pad 300 (cushion pad 310 or back pad 320) may be manufactured through a process of foaming by chemical reaction in mold molding or the like.

Next, a method for manufacturing a porous structure according to an embodiment of the present invention will be described with reference to FIG. 16. FIG. 16 shows, as an example, how the porous structure 1 according to an embodiment of the present invention, which constitutes the cushion pad 310 or the back pad 320 shown in FIG. 15, is manufactured using a 3D printer. However, the method for manufacturing a porous structure described below can be suitably used to manufacture the porous structure 1 used for any purpose.
First, three-dimensional shape data (for example, three-dimensional CAD data) representing the three-dimensional shape of the porous structure 1 is created in advance using a computer.
Next, the three-dimensional shape data is converted into 3D modeling data 500 using a computer. The 3D printing data 500 is read into the control unit 410 of the 3D printer 400 when the modeling unit 420 of the 3D printer 400 performs modeling. , is configured to be shaped. The 3D modeling data 500 includes, for example, slice data representing the two-dimensional shape of each layer of the porous structure 1.
Next, the porous structure 1 is shaped using the 3D printer 400. The 3D printer 400 may perform modeling using any modeling method, such as a stereolithography method, a powder sintering method, a fused deposition method (FDM method), or an inkjet method. FIG. 16 shows how modeling is performed using a fused deposition modeling method (FDM method).
The 3D printer 400 includes, for example, a control unit 410 configured by a CPU or the like, a modeling unit 420 that performs modeling under the control of the control unit 410, and a printer for placing the object to be modeled (i.e., the porous structure 1). It includes a support stand 430 and a container 440 in which the support stand 430 and the shaped object are accommodated. When using the fused deposition modeling method (FDM method) as in this example, the modeling section 420 is configured to discharge the main material MM that will ultimately constitute the modeled object (i.e., the porous structure 1). It has a main material nozzle 421 and a support material nozzle 422 configured to discharge a support material SM that supports the main material MM during modeling. As the main material MM, it is preferable to use flexible resin or rubber, and it is particularly preferable to use flexible resin.
In the 3D printer 400 configured in this way, first, the control unit 410 reads the 3D printing data 500, and based on the three-dimensional shape included in the read 3D printing data 500, the main material MM is sent to the printing unit 420. , each layer is sequentially modeled while controlling the support material SM to be discharged. At this time, parts of the porous structure 1 other than the voids (that is, the skeleton portion 2 and the membrane 3) are shaped using the main material MM, and the void portions of the porous structure 1 are formed using the support material SM. .
After the modeling by the 3D printer 400 is completed, the support material SM is removed from the modeled object. Thereby, the porous structure 1 (as a result, the cushion pad 310 or the back pad 320) is finally obtained as a shaped article.

Although not shown in the drawings, a case will be described in which modeling is performed using a stereolithography method instead of a fused deposition modeling method (FDM method).
In this case, the 3D printer 400 includes, for example, a control unit 410 configured by a CPU or the like, a modeling unit 420 that performs modeling under the control of the control unit 410, and a modeled object to be modeled (i.e., the porous structure 1). It includes a support base 430 on which to place the object, and a container 440 in which the liquid resin (not shown), the support base 430, and the molded object are accommodated. When using a stereolithographic method as in this example, the modeling section 420 has a laser irradiator (not shown) configured to irradiate ultraviolet laser light. The container 440 is filled with liquid resin. When the liquid resin is hit by ultraviolet laser light emitted from a laser irradiator, it hardens and becomes a flexible resin.
In the 3D printer 400 configured in this way, the control unit 410 first reads the 3D printing data 500 and applies an ultraviolet laser beam to the printing unit 420 based on the three-dimensional shape included in the read 3D printing data 500. Each layer is modeled in sequence while controlling the irradiation.
After the modeling by the 3D printer 400 is completed, the modeled object is taken out from the container 440. Thereby, the porous structure 1 (as a result, the cushion pad 310 or the back pad 320) is finally obtained as a shaped article.

Note that when the porous structure 1 is made of resin, the porous structure 1 as a modeled object may be heated in an oven after the modeling by the 3D printer 400 is completed. In that case, it is possible to strengthen the bonds between the layers constituting the porous structure 1 and thereby reduce the anisotropy of the porous structure 1, thereby further improving the properties of the porous structure 1 as a cushioning material. .
Furthermore, when the porous structure 1 is made of rubber, the porous structure 1 as a modeled object may be vulcanized after the modeling by the 3D printer 400 is completed.

Note that, as in a modification shown in FIG. 17, a plurality of types of materials with different compositions may be used as the main material MM during modeling by the 3D printer 400. In that case, the 3D printer 400 may include a plurality of main material nozzles 421. This makes it possible, for example, to configure the porous structure 1 as a modeled object with materials with different compositions depending on the part, and by extension, to have different properties (hardness, air permeability, etc.) depending on the part. become.
In conventional manufacturing methods using molds and the like, it has been difficult to construct a porous structure in one piece while also constructing the porous structure using materials with different blends in different parts. Therefore, when constructing different parts of the porous structure using materials with different compositions, multiple separate porous structures made of materials with different compositions are manufactured separately, and the resulting porous structures are interconnected. , it was necessary to bond them together using adhesive or the like. Therefore, manufacturing takes time and effort.
However, if the 3D printer 400 is used, it becomes possible to easily and quickly construct a structure in one piece and to construct the structure using materials with different compositions depending on the part.

FIG. 18(a) shows an example of a cross section of the cushion pad 310 in FIG. 15 taken along line GG parallel to the left-right direction. In the example of FIG. 18A, the porous structure 1 constituting the cushion pad 310 has a first portion 11 constituting the front side portion of the main pad portion 311 and a second portion 12 constituting the side pad portion 312. and a third portion 13 constituting the back surface side portion of the main pad portion 311, which are integrally constructed.
At this time, it is preferable that the second portion 12 is harder than the first portion 11. Thereby, the seated person can feel that he or she is being firmly held by the side pad portions 312 on both the left and right sides.
Further, it is preferable that the first portion 11 is harder than the third portion 13. As a result, when the seated person takes a seat, the seated person can feel a feeling of sitting that is soft at the beginning and becomes hard later on.
Note that the second portion 12 and the third portion 13 may have the same hardness.
Further, the entire main pad portion 311 may be configured to have the same hardness.
As a method for adjusting the hardness of the first portion 11, second portion 12, and third portion 13 of the porous structure 1 as described above, for example, by using the manufacturing method shown in FIG. The first portion 11, the second portion 12, and the third portion 13 of the structure 1 may be made of different materials, and in addition/instead of that, the first portion 11, the second portion 13 of the porous structure 1 may be made of different materials. The configuration of each of the portion 12 and the third portion 13 (configuration of the skeleton portion 2 (diameter and shape of each cell hole, ratio A0/A1 of each bone portion 2B, width W0 of each bone constant portion 2B1, etc.), membrane 3 It is preferable to use a method of varying the presence/absence and number of parts, the ratio of the volume occupied by the skeleton part 2 to the volume of each part, etc.).

FIG. 18(b) shows an example of a cross section of the back pad 320 in FIG. 15 taken along line HH parallel to the left-right direction. In the example of FIG. 18(b), the porous structure 1 constituting the back pad 320 has a first portion 11 constituting the main pad portion 321 and a second portion 12 constituting the side pad portion 322. These are integrated into one.
At this time, it is preferable that the second portion 12 is harder than the first portion 11. This allows the seated person to feel securely held by the side pad portions 322 on both the left and right sides.
As a method for adjusting the hardness of the first portion 11 and the second portion 12 of the porous structure 1 as described above, for example, as in the example of FIG. A method of making the materials constituting each of the portion 11 and the second portion 12 different, and in addition to/instead of that, the configuration of each of the first portion 11 and the second portion 12 (skeletal portion 2 configuration (diameter and shape of each cell pore, ratio A0/A1 of each bone part 2B, width W0 of each bone constant part 2B1, etc.), existence and number of membranes 3, and proportion of the volume of each part occupied by the skeleton part 2. It is preferable to use a method of varying the volume ratio, etc.).

Evaluations of comparative examples and examples of the porous structure of the present invention will be described below.

[Examples 1-2]
Examples 1 and 2 of the porous structure of the present invention are each 3D-CAD models created on a PC. The porous structure models of Examples 1 to 2 all have the shapes of the examples shown in FIGS. 1 to 10, and the physical properties (rigidity, etc.) of the materials constituting each model are the same. The volume of the porous structure model of Examples 1 and 2 is approximately 500 cm ³ , which is equivalent to a typical seat pad test block (more specifically, a vehicle seat pad). In the porous structure models of Examples 1 and 2, the dimensions of the respective unit parts U are different from each other, and accordingly, the sizes of the respective first cell partition parts 21 and second cell partition parts 22 and the size of the skeleton part 2 are different. They have different thicknesses. In the models of Examples 1 and 2, a portion of each first virtual surface V1 constituting the porous structure is covered with the membrane 3.
Table 1 shows the diameter of each first cell hole C1 and the width W0 of each bone constant portion 2B1 in the models of Examples 1 and 2.
For each of Examples 1 and 2, the manufacturability and shape accuracy when applied to a seat pad are evaluated.
(Evaluation of manufacturability)
In the manufacturability evaluation, it is evaluated whether the load on a PC (personal computer) that processes the porous structure model of each example is realistic. If it can be processed by a general CAD PC in recent years, it will be evaluated as "○", if it can be processed by a PC with relatively high specifications in recent years, it will be evaluated as "△", and if it can be processed by a PC with relatively high specifications in recent years, it will be evaluated as "△". Even if your PC has the following, if it cannot be processed (processing speed becomes extremely slow, freezes, etc.), it will be evaluated as "x" (Table 1). The higher the evaluation of manufacturability, the more 3D shape data (CAD data) representing the 3D shape of the porous structure, and the higher the 3D shape data generated based on the 3D shape data, when considering recent computer processing capabilities. This means that it is easy to generate 3D printing data on a computer, and it is easy for a 3D printer to print according to the 3D printing data.
(Evaluation of shape accuracy when applied to seat pad)
In evaluating the shape accuracy when applied to a seat pad, the outer edge (outer contour) shape of the porous structure model in each example was made into the shape of a seat pad (more specifically, a vehicle seat pad). , evaluate whether the required shape accuracy can be obtained. If it is possible to form the shape required for a general seat pad (the minimum radius of curvature is approximately 10 mm), it will be evaluated as "○", and if it is difficult to form the shape required for a general seat pad, it will be evaluated as "×". ” (Table 1). A higher evaluation of the shape accuracy when applied to a seat pad means that the appearance when the porous structure is applied to a seat pad can be improved.

As can be seen from Table 1, Examples 1 and 2 having cell holes with a diameter of 5 mm or more can achieve sufficiently good manufacturability, and when applied to a seat pad, the shape accuracy and appearance are also good.

[Example 3]
Example 3 of the porous structure of the present invention is a 3D-CAD model created on a PC. The model of the porous structure of Example 3 has an example shape partially shown by dotted lines in FIG. In the model of Example 3, a part of each first virtual surface V1 constituting the porous structure is covered with the membrane 3.
Table 2 shows the ratio A0/A1 of each bone portion 2B in the model of Example 3.
Regarding Example 3, the touch feeling of the surface is evaluated.
(Evaluation of surface touch feeling)
In order to evaluate the surface touch feeling, a load-deflection diagram was created by analysis for the porous structure model of Example 3, and the initial slope (at the beginning of load application) of the created load-deflection diagram was calculated based on the surface It is evaluated as the touch feeling (Table 2). The softer the touch on the surface, the softer the touch will be given to the seated person at the beginning of sitting.

As can be seen from Table 2, Example 3, which has a medium surface touch feeling, has good applicability to seat pads for both luxury cars and sports cars.

[Examples 4-5]
Examples 4 to 5 of the porous structure of the present invention have the shapes shown in FIGS. 1 to 10, and the volume VB occupied by the skeleton 2 out of the volume VS of the porous structure 1 is Only the ratio (VB×100/VS [%]) is different from each other. The porous structures of Examples 4 and 5 have the same volume, the dimensions of each unit U, and the physical properties (rigidity, etc.) of the materials constituting each. In all of Examples 4 and 5, a portion of each first virtual surface V1 constituting the porous structure is covered with the membrane 3.
Table 3 shows the ratio of the volume VB occupied by the skeleton portion 2 to the volume VS of the porous structure 1 in Examples 4 to 5 (VB×100/VS [%]).
The 25% hardness is evaluated for each of Examples 4-5.
(25% hardness evaluation)
For each example porous structure, the load required to compress the porous structure of a 100 mm test block by 25% using an Instron compression tester in an environment of 23°C and 50% relative humidity ( N) was measured, and the measured value was defined as 25% hardness (Table 3).

As can be seen from Table 3, in Examples 4 and 5, the higher the value of VB×100/VS, the higher the 25% hardness, and thus the harder the porous structure. The 25% hardness in Examples 4 and 5 is good as a cushion material, particularly as a cushion material for seating (seat pad, etc.), and more particularly as a seat pad for a vehicle. A 25% hardness of 4 is better.

The porous structure of the present invention and the porous structure produced using the porous structure production method or 3D modeling data of the present invention are suitable for use in cushioning materials, and for seating. It is more suitable for use in cushioning materials (seat pads, etc.), and even more suitable for use in vehicle seat pads.

1: Porous structure, 2: Skeletal part, 2B: Bone part, 2Be: End of bone part, 2B1: Fixed bone part, 2B2: Bone change part, 2B21: End of bone change part on the connection part side, 2B22 : End of the bone change part on the constant bone part side, 2B23: Inclined surface of the bone change part, 2J: Connection part, 3: Membrane, 11: First part of the porous structure, 12: Second part of the porous structure 13: Third portion of porous structure, 21: First cell section, 22: Second cell section, 211: First annular section, 211L: First large annular section, 211S: First small annular section. 2111: Inner peripheral edge of first annular part, 222: Second annular part, 2221: Inner peripheral edge of second annular part, 300: Vehicle seat pad, 310: Cushion pad, 311: Main Pad section, 312: Side pad section, 320: Back pad, 321: Main pad section, 322: Side pad section, 400: 3D printer, 410: Control section, 420: Modeling section, 421: Main material nozzle, 422: Support Material nozzle, 430: Support base, 440: Container, MM: Main material, SM: Support material, 500: 3D modeling data, C: Cell hole, C1: First cell hole, C2: Second cell hole, O : skeleton line, U: unit part of porous structure, V1: first virtual surface, V1L: first large virtual surface, V1S: first small virtual surface, V2: second virtual surface

Claims (9)

A porous structure made of flexible resin or rubber,
The porous structure includes a skeleton portion throughout the porous structure,
The skeleton part is
multiple bones,
a plurality of connecting parts each connecting the ends of the plurality of bone parts;
It is composed of
The skeleton portion has a plurality of first annular portions, each of which is configured in an annular shape from a plurality of the bone portions and a plurality of the joint portions,
Each of the first annular portions defines a first virtual surface by its inner peripheral edge,
at least one of the first virtual surfaces is covered with a membrane;
A porous structure, wherein each cell pore of the porous structure has a diameter of 5 mm or more and less than 30 mm. The skeleton portion has a first cell partition portion that partitions a first cell hole, which is the cell hole, inside;
The first cell section has a plurality of first annular parts,
The plurality of first annular parts constituting the first cell division part are connected to each other so that the first virtual planes partitioned by the inner peripheral side edges of each part do not intersect with each other,
The porous material according to claim 1, wherein the first cell pores are defined by the plurality of first annular parts and the plurality of first virtual planes respectively defined by the plurality of first annular parts. Structure. The plurality of first annular portions constituting the first cell section are:
a first small annular portion whose inner circumferential side edge defines a first small virtual surface;
a first large annular portion that defines a first large imaginary surface having an area larger than the first small imaginary surface by its inner peripheral side edge;
The porous structure according to claim 2, comprising: 4. The porous structure of claim 3, wherein at least one of the first small virtual surfaces is covered with a membrane. The porous structure according to claim 3 or 4, wherein at least one of the first large virtual surfaces is covered with a membrane. The porous structure according to any one of claims 3 to 5, wherein at least one of the first virtual surfaces has a polygonal shape. The porous structure according to any one of claims 1 to 6, wherein the porous structure is used for a seat pad. The porous structure according to any one of claims 1 to 7, wherein the porous structure is formed by a 3D printer. A method for manufacturing a porous structure, comprising manufacturing the porous structure according to any one of claims 1 to 7 using a 3D printer.

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