EP4785819A1

EP4785819A1 - Footwear and insole

Info

Publication number: EP4785819A1
Application number: EP24874676.0A
Authority: EP
Inventors: Mizuho IRIE; Shinsaku WAKASUGI; Yuichiro Okamoto; Kazushige Noda
Original assignee: Asics Corp
Current assignee: Asics Corp
Priority date: 2023-10-05
Filing date: 2024-10-03
Publication date: 2026-08-05
Also published as: WO2025075076A1; JP2025064026A; CN121969276A

Abstract

Footwear includes a sole, an upper, and a buffer material 30. The upper is provided above the sole and surrounds a foot insertion part. The buffer material 30 is accommodated within the foot insertion part. The buffer material 30 is constituted by at least two members of a first member 40 located on the upper side and a second member 50 located on the lower side that are superimposed. The first member 40 includes a projection portion 42 that projects in the direction of the sole at a position corresponding to a heel portion, and the first member 40 covers the entirety of the second member 50 in plan view. The second member 50 has an opening 52 configured to accommodate a heel portion.

Description

TECHNICAL FIELD

The present disclosure relates to footwear and an insole.

BACKGROUND ART

Footwear that includes a buffer material, such as a midsole, disposed between the upper and the sole is known. For example, Patent Literature 1 describes footwear having a removable outsole, midsole, and upper. On the bottom surface of the midsole of the footwear, multiple protrusions are provided to mate with pockets on the outsole. The protrusions are separated by slots to mate with raised walls provided in the pockets. Also, the footwear is configured to be customizable for each user by replacing the midsole, for example.

RELATED-ART LITERATURE

PATENT LITERATURE

Patent Literature 1: Specification of U.S. Patent No. 9737109

SUMMARY OF INVENTION

TECHNICAL PROBLEM

However, although the footwear described in Patent Literature 1 is configured such that the midsole is replaceable to ensure the comfort according to the user's preference, different properties cannot be obtained with a single midsole.
The present disclosure has been made in view of such a situation, and a purpose thereof is to provide footwear and an insole that can improve the cushioning properties and stability.

SOLUTION TO PROBLEM

Footwear according to one embodiment of the present disclosure includes a sole, an upper provided above the sole and surrounding a foot insertion part, and a buffer material accommodated within the foot insertion part. The buffer material is constituted by at least two members of a first member located on the upper side and a second member located on the lower side that are superimposed. The first member includes a projection portion that projects in the direction of the sole at a position corresponding to a heel portion, and the first member covers the entirety of the second member in plan view. The second member has an opening configured to accommodate a heel portion.
Another embodiment of the present disclosure is an insole. This insole is accommodated within a foot insertion part of footwear including a sole and an upper that is provided above the sole and surrounds the foot insertion part. The insole is constituted by at least two members of a first member located on the upper side and a second member located on the lower side that are superimposed. The first member includes a projection portion that projects in the direction of the sole at a position corresponding to a heel portion, and the first member covers the entirety of the second member in plan view. The second member has an opening configured to accommodate a heel portion.
Optional combinations of the aforementioned constituting elements, and methods, devices, and the like among which constituting elements or expressions in the present invention are mutually replaced are also effective as embodiments of the present invention.

ADVANTAGEOUS EFFECTS OF INVENTION

One embodiment of the present disclosure provides footwear and an insole that can improve the cushioning properties and stability.

BRIEF DESCRIPTION OF DRAWINGS

[Fig. 1] Fig. 1 is a plan view that schematically illustrates footwear according to an embodiment.
[Fig. 2] Fig. 2 is a plan view of a buffer material shown in Fig. 1.
[Fig. 3] Fig. 3 is a side view of the buffer material shown in Fig. 1.
[Fig. 4] Fig. 4 is a bottom view of the buffer material shown in Fig. 1.
[Fig. 5] Fig. 5 is a rear view of the buffer material shown in Fig. 1.
[Fig. 6] Fig. 6 is a plan view of a second member shown in Fig. 2.
[Fig. 7] Fig. 7 is a plan view of a second member according to a first modification.
[Fig. 8] Fig. 8 is a plan view of a second member according to a second modification.
[Fig. 9] Fig. 9 is a plan view of a second member according to a third modification.
[Fig. 10] Fig. 10 is a plan view of a second member according to a fourth modification.
[Fig. 11] Fig. 11 is a plan view of a second member according to a fifth modification.
[Fig. 12] Fig. 12 is a plan view of a second member according to a sixth modification.
[Fig. 13] Fig. 13 is a sectional view taken along line A-A in Fig. 2.
[Fig. 14] Fig. 14 is a sectional view taken along line B-B in Fig. 2.
[Fig. 15] Fig. 15 is a plan view of a toe side portion of the second member shown in Fig. 2.
[Fig. 16] Fig. 16 is a plan view of a toe side portion of a second member according to a seventh modification.
[Fig. 17] Fig. 17 is a diagram that schematically shows shapes of a first member shown in Fig. 2 and the second member shown in Fig. 2 in a no-load state.
[Fig. 18] Fig. 18 is a diagram that schematically shows shapes of the first member shown in Fig. 2 and the second member shown in Fig. 2 in a state where a first load is applied.
[Fig. 19] Fig. 19 is a diagram that schematically shows shapes of the first member shown in Fig. 2 and the second member shown in Fig. 2 in a state where a second load is applied.

DESCRIPTION OF EMBODIMENTS

In the following, the present disclosure will be described based on a preferred embodiment with reference to each drawing. In the embodiment and modifications, like reference characters denote like or corresponding constituting elements, and the repetitive description will be omitted as appropriate. Also, the dimensions of a member may be appropriately enlarged or reduced in each drawing in order to facilitate understanding. Further, in each drawing, part of a member less important in describing the embodiment may be omitted.
Further, terms including ordinal numbers, such as "first" and "second", are used to describe various constituting elements. However, such terms are used only to distinguish one constituting element from another and do not limit the constituting elements.
Fig. 1 is a plan view that schematically illustrates footwear 100 according to an embodiment. Each drawing mentioned below, including Fig. 1, illustrates footwear for a right foot, unless otherwise specified. However, the description in the present specification is also applicable to footwear for a left foot. Also, in each drawing mentioned below, illustration of a shoelace is omitted.
The footwear 100 of the present embodiment can be used for walking shoes, running shoes, safety shoes, and sports shoes for tennis or basketball, for example, and the use of the footwear 100 is not limited. The footwear 100 includes a sole 10, an upper 20, and a buffer material 30. The sole 10 is a portion to be in contact with the ground. The upper 20 surrounds an internal space as a foot insertion part 20a for accommodating a foot. The upper 20 is provided above the sole 10 and joined to the sole 10 by bonding or the like. The buffer material 30 is used by being accommodated within the foot insertion part 20a. These will be detailed below.
A direction extending along a center line La with respect to a width direction of the footwear 100 as shown in Fig. 1 will be referred to as a "longitudinal direction" or "foot length direction". Accordingly, a width direction is a direction perpendicular to the center line La. Also, the direction toward the toe side along the center line La will be referred to as the "front side" or "front", and the heel side opposite thereto will be referred to as the "rear side" or "rear". In a state where the footwear 100 is placed on a horizontal plane (hereinafter, referred to as a "horizontal state"), the upper side will be referred to as the "upper side" or "above", and the opposite side will be referred to as the "lower side" or "below". Also, in the horizontal state, a direction extending vertically will be referred to as a "vertical direction". In each drawing, the frontward direction in the longitudinal directions is shown as the positive direction of the X-axis, the direction toward the medial side in the width directions is shown as the positive direction of the Y-axis, and the upward direction in the vertical directions is shown as the positive direction of the Z-axis.
In the footwear 100, a portion corresponding to the metatarsal bones with respect to a longitudinal direction will be referred to as a midfoot portion. Also, in the footwear 100, a portion in front of the midfoot portion in a longitudinal direction will be referred to as a forefoot portion, and a portion in the rear of the midfoot portion in a longitudinal direction will be referred to as a rearfoot portion. The forefoot portion is a portion that almost corresponds to the phalanges, and the rearfoot portion is a portion that almost corresponds to the tarsals. When the longitudinal length of the footwear 100 is regarded as 100%, the midfoot portion almost corresponds to a region from 30% to 80% from the tip, occupying a range parallel with a straight line perpendicular to the center line La. Also, the forefoot portion almost corresponds to a region from 0% to 30% from the tip, and the rearfoot portion almost corresponds to a region from 80% to 100% from the tip.
In the rearfoot portion of the upper 20, a wearing opening 20b through which a foot is inserted is formed. Also, from the wearing opening 20b toward the front in the upper 20, a central opening 20c is formed. Along the edge of the central opening 20c of the upper 20, grommets 20h are formed such that a shoelace passes therethrough. Inside the central opening 20c, a shoe tongue 70 is provided. The central opening 20c may not necessarily be formed in the upper 20, and the upper 20 may have a so-called monosock structure. Similarly, the grommets 20h may not necessarily be formed in the upper 20, and the shoe tongue 70 may also not be provided.
The buffer material 30 will be described. The buffer material 30 is formed of a flexible material. When a wearer wears the footwear 100, the buffer material 30 intervenes between the foot and the sole 10 to cushion the impact applied to the foot. The buffer material 30 functions as an insole. The buffer material 30 may be removable through the wearing opening 20b of the upper 20.
Fig. 2 is a plan view of the buffer material 30 viewed from above. Fig. 3 is a side view of the buffer material 30 viewed from the lateral side. Fig. 4 is a bottom view of the buffer material 30 viewed from below. Fig. 5 is a rear view of the buffer material viewed from the heel side. As shown in Fig. 2 to Fig. 5, the buffer material 30 includes a first member 40 located on the upper side and a second member 50 located on the lower side. The first member 40 and the second member 50 are superimposed on each other. The buffer material 30 may include a member other than the first member 40 and the second member 50 but is constituted by at least the two members of the first member 40 and the second member 50 superimposed. In the present embodiment, the first member 40 is located as the top surface of the buffer material 30.
As illustrated in Fig. 2, the first member 40 covers the entirety of the second member 50 in plan view. In other words, the wearer's foot only comes into contact with the first member 40 of the buffer material 30 and does not come into contact with the second member 50. In Fig. 2, the second member 50 covered by the first member 40 is indicated by a dotted line. As shown in Fig. 4, the first member 40 includes a projection portion 42 that projects from the bottom surface of the first member 40 toward the sole 10 at a position corresponding to a heel portion of the wearer's foot.
The top surface of the first member 40 may be uneven to follow the shape of a foot. For example, a certain region of the top surface of the first member 40 including a position corresponding to the heel portion may have a cup shape that follows the shape of the heel portion. Also, for example, a certain region of the top surface of the first member 40 including a position corresponding to the arch may have a mountain-like shape with a convex formed at the middle in a longitudinal direction so as to follow the shape of the arch, as shown in Fig. 3. This can reduce the gap between the foot and the buffer material 30, thereby improving the fit.
The second member 50 is located below the first member 40 and supports the first member 40 in a certain region including at least the heel portion. In the present embodiment, the second member 50 has a shape that follows the contour of the first member 40 in plan view in a region including the entire rearfoot portion and part of the midfoot portion. As shown in Fig. 4, the second member 50 includes an opening 52 penetrating in a vertical direction at a position corresponding to the heel portion. The opening 52 is an opening that can accommodate the projection portion 42 of the first member 40 and is configured to accommodate at least part of the projection portion 42. The second member 50 can release the pressing force due to a load applied to the first member 40, downward through the opening 52.
As shown in Fig. 3, in the present embodiment, the bottom surface of the buffer material 30, formed by the bottom surface of the first member 40 and the bottom surface of the second member 50, has a substantially flat shape. Accordingly, the wearer is less likely to feel a step formed by the boundary between the first member 40 and the second member 50 and can comfortably wear the footwear with the first member 40 and the second member 50 smoothly connected along the bottom surface.
The thickness in a vertical direction of the forefoot portion of the buffer material 30 is in the range from 3 mm to 20 mm inclusive and may preferably be in the range from 4 mm to 5.5 mm inclusive. This can reduce the feeling of being pushed up by the ground and ensure the cushioning properties. With the thickness in a vertical direction of the forefoot portion of the buffer material 30 set to 3 mm or greater, effects can be obtained such as being less likely to feel a step or foreign object such as a stone on the ground and ensuring the cushioning properties and reducing foot fatigue. Also, with the thickness in a vertical direction of the forefoot portion of the buffer material 30 set to 20 mm or less, effects can be obtained such as preventing interference with foot insertion and making the overall shape of the footwear 100 less likely to change. In particular, the thickness in a vertical direction of the rearfoot portion of the first member 40 may preferably be greater than or equal to the thickness of the forefoot portion. For example, the thickness of the first member 40 may increase from the forefoot portion side toward the rearfoot portion side. Similarly, the thickness of the second member 50 may also increase from the forefoot portion side toward the rearfoot portion side.
The circumferential edge of the buffer material 30 may be located along the outer edge of the foot insertion part 20a as a whole. In other words, the buffer material 30 may be configured such as to have a size corresponding to the foot insertion part 20a and such that the movement thereof within the foot insertion part 20a is restricted. In particular, it is preferable that the buffer material 30 is disposed along the outer edge of the foot insertion part 20a in the rearfoot portion. Accordingly, the buffer material 30 is positioned within the foot insertion part 20a, and the various effects provided by the buffer material 30, which will be described later, can be achieved more easily.
In the following, description will be made assuming that the circumferential edge of the buffer material 30 is located along the outer edge of the foot insertion part 20a.
Fig. 6 is a plan view of the second member 50. Fig. 13 is a sectional view taken along line A-A in Fig. 2. Fig. 14 is a sectional view taken along line B-B in Fig. 2. The top surface of the second member 50 includes a contact region 54 in contact with the first member 40 around the opening 52 in plan view. In the present embodiment, the contact region 54 of the second member 50 is in contact with the first member 40 without a gap along a circumferential direction around the opening 52. The top surface of the second member 50 further includes an inclined region 56 that is inclined in the direction of the sole 10 toward the opening 52, i.e., downward in Fig. 13 and Fig. 14, on the opening 52 side with respect to the contact region 54. In a state where the wearer's foot is not inserted into the foot insertion part 20a (hereafter, referred to as the "no-load state"), the inclined region 56 of the second member 50 is separated from the first member 40. In the no-load state, in a region of the top surface of the second member 50 located around the opening 52, the region in contact with the first member 40 is referred to as the contact region 54, and the region not in contact with the first member 40 is referred to as the inclined region 56.
The inclined region 56 of the second member 50 may have a tapered shape that narrows downward. The contact region 54 and the inclined region 56 may be smoothly connected to each other. That is, in the cross-sectional views shown in Fig. 13 and Fig. 14, a tangent to the contact region 54 at a boundary portion with the inclined region 56 and a tangent to the inclined region 56 at a boundary portion with the contact region 54 are identical. The inclined region 56 may be smoothly inclined downward toward the opening 52.
As shown in Fig. 6, the contact region 54 is located from a heel-side end point 58 of the second member 50 to a position in the range of 0.5 mm to 30 mm inclusive from the heel-side end point 58 toward the opening 52. More specifically, with the heel-side end point 58 of the second member 50 as the starting point of the contact region 54, the ending point thereof may be positioned at a distance 60 of 0.5 mm to 30 mm inclusive from the starting point along a shoe center axis SC, preferably at a distance of 3 mm to 20 mm inclusive from the starting point, and more preferably at a distance of 5 mm to 10 mm inclusive from the starting point. The shoe center axis SC may be a center line with respect to a width direction of the buffer material 30 or may be a line corresponding to a straight line connecting the center of the calcaneus of a standard wearer of the footwear 100 provided with the buffer material 30 and a point between the first toe and the second toe.
For example, the contact region 54 may be located in a range of the rearfoot portion in which, with a circumferential edge of the second member 50 as the starting point, the ending point thereof is positioned at a distance as described above along a direction perpendicular to the boundary with the inclined region 56. The contact region 54 need not completely surround the inclined region 56 in plan view and, for example, the toe-side end in a foot length direction of the contact region 54 may be positioned similarly to the toe-side end of the opening 52.
As shown in Fig. 13 and Fig. 14, in the no-load state, a gap is formed between an outer circumferential surface 44 of the projection portion 42 of the first member 40 and the inclined region 56 of the second member 50 that the outer circumferential surface 44 faces. The inclination of the outer circumferential surface 44 of the projection portion 42 of the first member 40 may be gentler than the inclination of the inclined region 56 of the second member 50 that the outer circumferential surface 44 faces. The inclination being gentler means the angle made with respect to a horizontal plane being smaller than that of the comparison object. The outer circumferential surface 44 of the projection portion 42 of the first member 40 and the inclined region 56 of the second member 50 have only to have the aforementioned relationship at a position where they face each other, and each of their inclinations may differ depending on the position. For example, as shown in Fig. 7, among the inclinations of the inclined region 56 of the second member 50, an inclination on the toe side with respect to the opening 52 may be gentler than an inclination on the heel side with respect to the opening 52. By making the inclination on the toe side of the inclined region 56 gentler, the feeling of being pushed up can be reduced.
The inclination of the outer circumferential surface 44 of the projection portion 42 of the first member 40 and the inclination of the inclined region 56 of the second member 50 may change toward the opening 52. Also, the distance along a vertical direction between the outer circumferential surface 44 of the projection portion 42 of the first member 40 and the inclined region 56 of the second member 50 may increase toward the opening 52. The slope of the outer circumferential surface 44 of the projection portion 42 and the slope of the inclined region 56 have different inclinations. The slope of the inclined region 56 has a larger inclination than the slope of the outer circumferential surface 44 of the projection portion 42. Therefore, a gap space can be provided between the projection portion 42 of the first member 40 and the opening 52 of the second member 50. Although Fig. 13 and Fig. 14 show an example in which the outer circumferential surface 44 of the projection portion 42 is a smooth surface, the outer circumferential surface 44 may have an uneven shape, for example.
In the no-load state, the projection portion 42 of the first member 40 does not come into contact with a facing surface that the projection portion 42 faces in the direction of the sole 10 through the opening 52 of the second member 50. The facing surface as used herein may be the top surface of the sole 10, for example. When the buffer material 30 includes a member, such as a sheet member, on the sole 10 side of the second member 50 or when another member is disposed between the buffer material 30 and the sole 10, the facing surface may be the top surface of such a member. Examples of the sheet member and another member described above include a midsole and an insole.
The second member 50 may include an unjoined region that is not joined with the first member 40, within the contact region that faces the first member 40. Here, the contact region means a region where the first member 40 and the second member 50 are in contact in the no-load state. That is, in the contact region, the first member 40 and the second member 50 may be partially joined or may not be joined.
Accordingly, in response to the load from the wearer, the first member 40 and the second member 50 slide against each other to support the load while changing the positional relationship therebetween, so that the stability is further enhanced. If the first member 40 and the second member 50 are entirely joined in the contact region, deformation caused by the load may place a burden on a specific part, and the buffer material 30 may deteriorate. With the second member 50 including an unjoined region, a longer life of the buffer material 30 may also be achieved.
Also, even when the second member 50 includes an unjoined region, the occurrence of deviation in the positional relationship between the first member 40 and the second member 50 may be suppressed by forming the first member 40 and the second member 50 in specific shapes corresponding to each other in the unjoined region. For example, in order to suppress the sliding of the first member 40 against the second member 50 due to the load, a groove or uneven shapes may be provided along a circumferential direction around the opening 52 in plan view, in the contact region between the first member 40 and the second member 50. Also, sliding can be suppressed by matching the shapes of portions of the first member 40 and the second member 50 that each correspond to the arch in the midfoot portion.
A joined region where the first member 40 and the second member 50 are joined is preferably located in the range from 30% to 65% inclusive, more preferably in the range from 45% to 62% inclusive, from a heel-side end point 32 of the buffer material 30 along the shoe center axis SC shown in Fig. 2. The ranges described above indicate ranges when the length between the heel-side end point 32 of the buffer material 30 and a toe-side end point 34 of the buffer material 30 along the shoe center axis SC is defined as the length of the buffer material 30 and regarded as 100%. The joining in the joined region may be mechanical joining or may be chemical joining, such as bonding using an adhesive or the like. One example of mechanical joining is a structure in which the most protruding point at an end of the second member 50 in the joined region is fitted into a step provided in the first member. Another example of mechanical joining is a fitting structure configured by providing a groove or an uneven shape on each of the contact surfaces of the first member 40 and the second member 50. Yet another example of mechanical joining is an example in which sliding is prevented with the first member 40 and the second member 50 structured to stereoscopically match in an arch portion of the midfoot portion. Thus, with the first member 40 and the second member 50 partially joined, the stability of the midfoot portion can be enhanced, and positional deviation between the first member 40 and the second member 50 can be suppressed.
The hardness of the first member 40 is less than or equal to the hardness of the second member 50. The hardness of the first member 40 may be the same as the hardness of the second member 50 or may be lower than the hardness of the second member 50. When the hardness of the first member 40 is lower than the hardness of the second member 50, in response to the load from the wearer, the first member 40 is deformed more greatly than the second member 50 while being supported by the second member 50 with higher hardness to support the wearer's foot, so that the cushioning properties and stability are further enhanced. Also, by making the hardness of the first member 40, which is in direct contact with the wearer's foot, relatively low, it can be made to feel smooth for the foot. Although adjustment may be made based on the hardness and thickness of the sole 10, the hardness of the first member 40 may be 30 degrees to 60 degrees inclusive, and the hardness of the second member 50 may be 40 degrees to 80 degrees inclusive, as measured with the ASKER Durometer Type C, for example.
The first member 40 and the second member 50 may be formed of various materials having desired properties. For example, the first member 40 may be formed of resin foam made of a TPE (thermoplastic elastomer), such as EVA resin (ethylene-vinyl acetate copolymer) and TPU resin (thermoplastic polyurethane). The first member 40 may also be a structure constituted by light-curing resin with a urethane acrylate or the like as the main material. The second member 50 may be formed of the same material as the first member 40 or may be formed of a different material. Each of the first member 40 and the second member 50 may be constituted by a single member or may be constituted by multiple members. Also, the first member 40 and the second member 50 may be separate bodies, or a foam material having different hardness, such as a GEL (registered trademark) material, may be provided inside or on a surface. In this case, the smoothness for a foot or cushioning properties can be changed.
The opening 52 of the second member 50 may have a planar shape of which the dimension in a foot length direction is larger than the dimension in a foot width direction. Also, the opening 52 may be provided within the range from 5% to 40% inclusive from the heel-side end point of the foot insertion part 20a in a foot length direction. In the present embodiment, since the circumferential edge of the buffer material 30 is located along the outer edge of the foot insertion part 20a, the heel-side end point of the foot insertion part 20a is equal to the heel-side end point 32 of the buffer material 30. That is, between the heel-side end point 32 and the toe-side end point 34 of the buffer material 30, the opening 52 is located within the range from 5% to 40% inclusive from the heel-side end point 32 along the shoe center axis SC shown in Fig. 2. Thus, since the opening 52 is provided at a position corresponding to the wearer's heel portion, the load can be effectively supported.
In order to achieve the effect described above more effectively, the dimension in a foot width direction in the planar shape of the opening 52 of the second member 50 may be largest at the center position corresponding to the heel portion. Also, the planar shape of the opening 52 may be substantially line-symmetric with respect to a heel center axis HC shown in Fig. 2. The heel center axis HC means a straight line connecting the center of the calcaneus of a standard wearer of the footwear 100 and a point between the third toe and the fourth toe. The planar shape of the opening 52 may preferably have no corners. This makes the wearer less likely to feel a sense of incongruity.
The planar shape of the opening 52 may be an elliptical shape or may be an egg shape of which the dimension in a foot width direction is larger on the heel side than on the toe side as shown in Fig. 6. When the planar shape of the opening 52 is an elliptical shape or egg shape, for example, a straight line passing through the major axis of the planar shape may pass between the shoe center axis SC and the heel center axis HC.
Fig. 7 to Fig. 12 are plan views of second members 50A to 50F according to first through sixth modifications. The second members 50A to 50F respectively have openings 52A to 52F of which the planar shapes are different from the planar shape of the opening 52 of the second member 50. As shown in Fig. 7, the planar shape of the opening 52A of the second member 50A is a substantially elliptical shape in which a direction along the heel center axis HC is a long side direction. As shown in Fig. 8, the planar shape of the opening 52B of the second member 50B is a substantially rounded rectangular shape in which a direction along the heel center axis HC is a long side direction. As shown in Fig. 9, the planar shape of the opening 52C of the second member 50C is a substantially circular shape of which the center is positioned along the heel center axis HC. As shown in Fig. 10, the planar shape of the opening 52D of the second member 50D is a substantially elliptical shape in which a direction along the heel center axis HC is a long side direction, and the medial side of the toe-side end projects toward the toe side compared to the lateral side thereof. As shown in Fig. 11, the planar shape of the opening 52E of the second member 50E is a shape that is substantially line-symmetric with respect to the heel center axis HC and includes a total of four portions that each project in a direction inclined to an outer side in a width direction from the heel center axis HC on the toe side or the heel side. As shown in Fig. 12, the planar shape of the opening 52F of the second member 50F is a shape that is substantially line-symmetric with respect to the heel center axis HC and includes a total of 10 portions that project radially from a substantial center. Since the second members 50A to 50F are similar to the second member 50 except for the configurations described above, the description thereof will be omitted.
When one of the second members 50A to 50F is used instead of the second member 50 included in the buffer material 30, the first member 40 may be used as it is, or a first member (not illustrated) that includes a projection portion (not illustrated) having a shape different for each of the openings 52A to 52F of the second members 50A to 50F may be used instead of the first member 40. Even when one of such second members 50A to 50F is used, the same effect can be obtained as when the second member 50 is used.
In the example shown in Fig. 2, the second member 50 is located within a range from the heel-side end point of the foot insertion part 20a to 70% or less in a foot length direction. That is, in the example shown in Fig. 2, the second member 50 is located within a range of which the starting point is the heel-side end point 32 of the buffer material 30 and of which the ending point is positioned at 70% or less of the length from the end point 32 to the toe-side end point 34 along the shoe center axis SC. Also, a lateral side end 68a and a medial side end 68b on the toe side of the second member 50 are located at positions other than a position corresponding to the hallux ball and a position corresponding to the little toe ball. This allows the second member 50 to support the wearer's midfoot portion and the like while ensuring free movement of the forefoot portion. The range in which the second member 50 is located is not limited to the range described above, and the second member 50 may be located over the entire surface of the buffer material 30 in plan view, for example.
Fig. 15 is a plan view of a toe side portion of the second member 50. The second member 50 has a shape that projects toward the toe side at a position along the heel center axis HC in plan view. This allows the second member 50 to perform the function of supporting the arch in the midfoot portion more effectively.
Fig. 16 is a plan view of a toe side portion of a second member 50G according to a seventh modification. The second member 50G has a shape in which a recess is provided on the toe side at a position between the shoe center axis SC and the heel center axis HC in plan view. Since the second member 50G is similar to the second member 50 except for the configuration described above, the description thereof will be omitted.
In the following, the states where the first member 40 and the second member 50 are deformed in response to a load F will be described with reference to Fig. 17 to Fig. 19. The load F is a load applied downward from the top surface of the buffer material 30 at a position corresponding to the heel portion. Fig. 17 is a diagram that schematically shows the shapes of the first member 40 and the second member 50 in the no-load state. Fig. 18 is a diagram that schematically shows the shapes of the first member 40 and the second member 50 in a state where a first load F1 is applied. Fig. 19 is a diagram that schematically shows the shapes of the first member 40 and the second member 50 in a state where a second load F2 is applied.
As shown in Fig. 17, in the no-load state (the load F = 0), a gap is formed between the outer circumferential surface 44 of the projection portion 42 of the first member 40 and the inclined region 56 of the second member 50 that the outer circumferential surface 44 faces, so that the outer circumferential surface 44 is located not to come into contact with the inclined region 56. Also, the projection portion 42 of the first member 40 does not come into contact with a facing surface 12 that the projection portion 42 faces in the direction of the sole 10 through the opening 52 of the second member 50. A gap space is formed between the projection portion 42 of the first member 40 and the opening 52 of the second member 50.
When the load F is applied to the top surface of the first member 40, the first member 40 is pressed downward as the load F increases. The distance along a vertical direction between the outer circumferential surface 44 of the projection portion 42 of the first member 40 and the inclined region 56 of the second member 50 increases toward the opening 52. Accordingly, when the first member 40 is pressed downward, the first member 40 is deformed such that the contact region between the outer circumferential surface 44 and the inclined region 56 gradually expands from the periphery of the opening 52 toward the center. In other words, the contact region between the outer circumferential surface 44 of the projection portion 42 and the inclined region 56 gradually expands from a position away from the opening 52. This becomes more pronounced when the inclination of the inclined region 56 is larger than the inclination of the outer circumferential surface 44. Thus, with the increase of the load F, the gap between the outer circumferential surface 44 and the inclined region 56 is filled, and the gap space is reduced.
Although not shown in Fig. 17, the contact region 54 (see Fig. 14, for example) of the second member 50, of which the inclination is smaller than the inclined region 56, is in contact with the bottom surface of the first member 40. Therefore, with the increase of the load F, the first member 40 is deformed such as to fill the gap while the movement of the first member 40 with respect to the second member 50 is restricted to some extent. Since the second member 50 is disposed along the outer edge of the foot insertion part 20a in the rearfoot portion, the deformation thereof is suppressed. Thereafter, when the load F reaches a predetermined first load F1, the gap between the outer circumferential surface 44 of the projection portion 42 and the inclined region 56 is filled, as shown in Fig. 18. The displacement at the time is defined as first displacement. In this way, since the first member 40 is deformed to fill the gap until the displacement reaches the first displacement, the increase of the load F with respect to the increase of the displacement is relatively small, so that the cushioning properties can be easily obtained. Also, since the contact region expands from the periphery of the opening 52 toward the center, even when the direction in which the load F is applied slightly slants from a vertical direction, the first member 40 can be displaced toward the center of the opening 52 while being supported by the second member 50. Therefore, deviation in a horizontal direction is reduced, and the stability can be enhanced more easily.
When the load F applied to the top surface of the first member 40 further increases to reach a predetermined second load F2, the projection portion 42 comes into contact with the facing surface 12 through the opening 52, as shown in Fig. 19. The displacement at the time is defined as second displacement. When the load F applied to the top surface of the first member 40 further increases, the first member 40 and the second member 50 are compressed.
The period during which the load F increases from the no-load state to the first load F1 is the period until the gap between the outer circumferential surface 44 of the projection portion 42 and the inclined region 56 is filled; since the first member 40 can move relatively freely, the displacement with respect to the load F is relatively large. Accordingly, during this period, the cushioning properties of the buffer material 30 are ensured.
The period during which the load F increases from the first load F1 to the second load F2 is the period until the projection portion 42 comes into contact with the facing surface 12 in a state where the gap between the outer circumferential surface 44 of the projection portion 42 and the inclined region 56 is filled; since the first member 40 moves while the movement thereof is partially restricted, the displacement with respect to the load F is reduced. Accordingly, during this period, the stability of the buffer material 30 is enhanced while the cushioning properties thereof are reduced.
During the period when the load F increases beyond the second load F2, the movement of the projection portion 42 is mostly restricted, and the first member 40 and the second member 50 undergo compressive deformation, so that the displacement with respect to the load F is further reduced. Accordingly, during this period, the stability of the buffer material 30 is further enhanced. When the load F decreases from a state where the load F is greater than the second load F2 to the no-load state, the deformation states described above transition in reverse order.
When a wearer wearing the footwear 100 repeats movements such as walking, the first member 40 and second member 50 repeatedly transition between the above-mentioned deformation states each time the wearer lands on the ground. Therefore, the foot can be protected as the cushioning properties are high in an early stage of landing, and the wearer's movements can be performed stably as the stability is high when the wearer lands and steps.
The buffer material 30 may be configured such that the first member 40 and the second member 50 are detachable. In this case, multiple first members 40 that each differ in at least one of the shape or material and second members 50 that each differ in at least one of the shape or material may be prepared, and a buffer material 30 constituted by an arbitrary combination thereof may be produced. This can produce a buffer material 30 having different properties for each wearer. Also, with regard to the buffer material 30 worn out by use, one of the first member 40 and the second member 50 may be replaceable. For example, when the first member 40 is more prone to wear out due to contact with the wearer's foot, replacing only the first member 40 can prevent unnecessary consumption of materials.
The present disclosure has been described based on an embodiment. The embodiment is intended to be illustrative only, and it will be obvious to those skilled in the art that various modifications to a combination of constituting elements or processes could be developed and that such modifications also fall within the scope of the present disclosure. Also, when the embodiment set forth above is generalized, the following aspects are obtained.

Aspect 1

Footwear, including:

a sole;
an upper provided above the sole and surrounding a foot insertion part; and
a buffer material accommodated within the foot insertion part,
wherein the buffer material is constituted by at least two members of a first member located on the upper side and a second member located on the lower side that are superimposed,
wherein the first member includes a projection portion that projects in the direction of the sole at a position corresponding to a heel portion, and the first member covers the entirety of the second member in plan view, and
wherein the second member has an opening configured to accommodate a heel portion.

Accordingly, in the footwear according to Aspect 1, the projection portion of the first member located on the upper side can be accommodated in the opening of the second member located on the lower side, at a position corresponding to a wearer's heel portion. Therefore, depending on the load, the projection portion can be placed in a state of being in contact with another part or a state of being not in contact with another part, so that both the cushioning properties and stability can be obtained. Also, since the first member covers the entirety of the second member in plan view, the wearer's foot does not come into contact while placed across the first member and the second member, which is less likely to give a sense of incongruity to the wearer.

Aspect 2

The footwear according to Aspect 1,

wherein a top surface of the second member includes a contact region in contact with the first member around the opening in plan view,
wherein the contact region is located from a heel-side end point of the second member to a position in the range of 0.5 mm to 30 mm inclusive from the heel-side end point toward the opening, and
wherein the top surface of the second member further includes an inclined region that is inclined in the direction of the sole toward the opening, on the opening side with respect to the contact region.

Accordingly, in the footwear according to Aspect 2, since the second member is in contact with the first member around the opening, deviation in the positional relationship between the first member and the second member can be suppressed, and lowering of the first member into the opening of the second member due to the load can also be suppressed. Therefore, with regard to the footwear according to Aspect 2, the cushioning properties are ensured, and the stability in a vertical direction is further enhanced.

Aspect 3

The footwear according to Aspect 2,
wherein a gap is formed between an outer circumferential surface of the projection portion and the inclined region that the outer circumferential surface faces, and the projection portion does not come into contact with a facing surface that the projection portion faces in the direction of the sole through the opening.
Accordingly, in the footwear according to Aspect 3, the cushioning properties are further enhanced as the projection portion moves in the gap when the load from the wearer's heel portion is in a range less than or equal to a predetermined value.

Aspect 4

The footwear according to any one of Aspects 1 through 3, wherein the second member includes an unjoined region that is not joined with the first member, in a contact region that faces the first member.
Accordingly, in the footwear according to Aspect 4, in response to the load from the wearer, the first member and the second member support the load while changing the positional relationship therebetween, so that the stability is further enhanced.

Aspect 5

The footwear according to any one of Aspects 1 through 4, wherein the hardness of the first member is less than or equal to the hardness of the second member.
Accordingly, in the footwear according to Aspect 5, in response to the load from the wearer, the first member is deformed more greatly than the second member while being supported by the second member to support the wearer's foot, so that the cushioning properties and stability are further enhanced.

Aspect 6

The footwear according to any one of Aspects 1 through 5, wherein the opening has a planar shape of which the dimension in a foot length direction is larger than the dimension in a foot width direction, and the opening is located within the range from 5% to 40% inclusive from a heel-side end point of the foot insertion part in a foot length direction.
Accordingly, in the footwear according to Aspect 6, since support is provided more effectively at a position corresponding more to the wearer's heel portion, the stability is further enhanced.

Aspect 7

The footwear according to any one of Aspects 1 through 6,

wherein the second member is located within a range from a heel-side end point of the foot insertion part to 70% or less in a foot length direction, and
wherein a lateral side end and a medial side end on the toe side of the second member are located at positions other than a position corresponding to the hallux ball and a position corresponding to the little toe ball.

Accordingly, in the footwear according to Aspect 7, the second member is not disposed at positions corresponding to the hallux ball and the little toe ball while supporting the wearer's midfoot portion and the like, so that free movement on the toe side can be ensured.

Aspect 8

An insole accommodated within a foot insertion part of footwear including a sole and an upper that is provided above the sole and surrounds the foot insertion part,

the insole being constituted by at least two members of a first member located on the upper side and a second member located on the lower side that are superimposed,
wherein the first member includes a projection portion that projects in the direction of the sole at a position corresponding to a heel portion, and the first member covers the entirety of the second member in plan view, and
wherein the second member has an opening configured to accommodate a heel portion.

Accordingly, footwear that accommodates the insole according to Aspect 8 can have the same effect as the footwear according to Aspect 1.

INDUSTRIAL APPLICABILITY

The present disclosure relates to footwear and an insole.

REFERENCE SIGNS LIST

10 sole, 12 facing surface, 20 upper, 20a foot insertion part, 30 buffer material, 32 heel-side end point, 40 first member, 42 projection portion, 44 outer circumferential surface, 50 second member, 52 opening, 54 contact region, 56 inclined region, 58 heel-side end point, 60 width, 68a lateral side end, 68b medial side end, 100 footwear

Claims

Footwear, comprising:
a sole;

an upper provided above the sole and surrounding a foot insertion part; and

a buffer material accommodated within the foot insertion part,

wherein the buffer material is constituted by at least two members of a first member located on the upper side and a second member located on the lower side that are superimposed,

wherein the first member includes a projection portion that projects in the direction of the sole at a position corresponding to a heel portion, and the first member covers the entirety of the second member in plan view, and

wherein the second member has an opening configured to accommodate a heel portion.
The footwear according to Claim 1,
wherein a top surface of the second member includes a contact region in contact with the first member around the opening in plan view,

wherein the contact region is located from a heel-side end point of the second member to a position in the range of 0.5 mm to 30 mm inclusive from the heel-side end point toward the opening, and

wherein the top surface of the second member further includes an inclined region that is inclined in the direction of the sole toward the opening, on the opening side with respect to the contact region.
The footwear according to Claim 2,
wherein a gap is formed between an outer circumferential surface of the projection portion and the inclined region that the outer circumferential surface faces, and the projection portion does not come into contact with a facing surface that the projection portion faces in the direction of the sole through the opening.
The footwear according to any one of Claims 1 through 3, wherein the second member includes an unjoined region that is not joined with the first member, in a contact region that faces the first member.
The footwear according to Claim 1, wherein the hardness of the first member is less than or equal to the hardness of the second member.
The footwear according to Claim 1, wherein the opening has a planar shape of which the dimension in a foot length direction is larger than the dimension in a foot width direction, and the opening is located within the range from 5% to 40% inclusive from a heel-side end point of the foot insertion part in a foot length direction.
The footwear according to Claim 1,
wherein the second member is located within a range from a heel-side end point of the foot insertion part to 70% or less in a foot length direction, and

wherein a lateral side end and a medial side end on the toe side of the second member are located at positions other than a position corresponding to the hallux ball and a position corresponding to the little toe ball.
An insole accommodated within a foot insertion part of footwear comprising a sole and an upper that is provided above the sole and surrounds the foot insertion part,
the insole being constituted by at least two members of a first member located on the upper side and a second member located on the lower side that are superimposed,

wherein the first member includes a projection portion that projects in the direction of the sole at a position corresponding to a heel portion, and the first member covers the entirety of the second member in plan view, and

wherein the second member has an opening configured to accommodate a heel portion.