EP4775074A1

EP4775074A1 - Sole and shoe

Info

Publication number: EP4775074A1
Application number: EP24862451.2A
Authority: EP
Inventors: Kazuki TOBA; Yutaro IWASA; Takuto ISHII; Noriko HAMANA; Yoshinori TATEISHI; Yasuyuki TAKADA
Original assignee: Asics Corp
Current assignee: Asics Corp
Priority date: 2023-09-09
Filing date: 2024-07-24
Publication date: 2026-07-15
Also published as: JPWO2025052795A1; WO2025052795A1

Abstract

A sole has a cup-shaped sole main body portion. The sole main body portion includes a flat plate-shaped bottom portion and a wall portion rising upward from an outer edge of the bottom portion. An inner groove extending along an outer edge of the bottom portion is formed on an inner peripheral surface of the wall portion, and an outer groove extending along an outer edge of the bottom portion is formed on an outer peripheral surface of the wall portion.

Description

TECHNICAL FIELD

[REFERENCE TO RELATED APPLICATIONS]

The present application claims priority based on JP-2023-146579 filed on September 9, 2023 , the entire disclosure of which is incorporated herein by reference.
The present disclosure relates to a sole and a shoe.

Background Information

As an exercise shoe used in coat based sports such as handball, a coat style shoe including a cup-shaped sole is known. In general, this type of shoe is formed have a thin bottom so that nimble footwork can be exhibited during exercise. However, since such a shoe is often used for daily wear, further pursuing of cushioning property and weight reduction is desired so as to obtain comfort in normal walking motion. Patent Documents 1 to 3 disclose a sole structure for improving cushioning property, but all of them inevitably have a thick bottom, and there is a concern about increase in weight due to a sole.

PRIOR ART DOCUMENTS

PATENT DOCUMENT

Patent Document 1: JP2021-186674A
Patent Document 2: JP2009-261902A
Patent Document 3: JP2008-532618A

SUMMARY OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

The present disclosure has been made in view of the above circumstances, and an object of the present disclosure is to provide a sole and a shoe that can achieve improvement in cushioning property and reduction in weight.

MEANS FOR SOLVING THE PROBLEMS

A sole of the present disclosure is a sole constituting a part of a shoe. The sole has a cup-shaped sole main body portion. The sole main body portion includes a flat plate-shaped bottom portion and a wall portion rising upward from an outer edge of the bottom portion. An inner groove extending along an outer edge of the bottom portion is formed on an inner peripheral surface of the wall portion, and an outer groove extending along an outer edge of the bottom portion is formed on an outer peripheral surface of the wall portion.
A shoe of the present disclosure has the sole and an upper arranged above the sole.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a perspective view schematically illustrating a shoe according to an embodiment of the present disclosure;
Fig. 2 is a perspective view of a sole;
Fig. 3 is a plan view of the sole;
Fig. 4 is a cross-sectional view taken along line IV-IV of Fig. 3;
Fig. 5 is a diagram of a sole main body portion as viewed from three directions;
Fig. 6 is a cross-sectional view taken along line VI-VI of Fig. 3;
Fig. 7 is a cross-sectional view taken along line VII-VII of Fig. 3;
Fig. 8 is a cross-sectional view taken along line VIII-VIII of Fig. 3;
Fig. 9 is a cross-sectional view illustrating a variation of a buffer member;
Fig. 10 is a cross-sectional view illustrating a variation of a buffer member;
Fig. 11 is a cross-sectional view illustrating a variation of a buffer member;
Fig. 12 is a cross-sectional view illustrating a variation of a buffer member;
Fig. 13 is a cross-sectional view illustrating a variation of a buffer member;
Fig. 14 is a cross-sectional view illustrating a variation of a buffer member;
Fig. 15 is a cross-sectional view illustrating a variation of a buffer member; and
Fig. 16 is a cross-sectional view illustrating a variation of a buffer member.

MODE FOR CARRYING OUT THE INVENTION

An embodiment of the present disclosure will be described with reference to the drawings. Fig. 1 is a perspective view schematically illustrating a shoe according to the embodiment of the present disclosure. A shoe 9 illustrated in Fig. 1 is a coat style shoe used in coat based sports such as handball. However, the shoe can be used without any trouble for normal wear, and use of the shoe is not particularly limited. A sole 1 constitutes a part of the shoe 9. In the present embodiment, the sole 1 and the shoe 9 for a left foot will be described, but the description is similarly applicable to a sole and a shoe for a right foot. The sole and the shoe for the right foot are formed to have a shape symmetrical or substantially symmetrical with the sole and the shoe for the left foot, respectively.
The shoe 9 includes the sole 1 and an upper 2 arranged above the sole 1. A hem portion of the upper 2 is joined to the sole 1 by a method such as pressing. A foot of a wearer wearing the shoe 9 is supported from below by the sole 1 and covered from above by the upper 2. The wearer is assumed to be a person of normal build having a foot adapted to size of the shoe 9. In the present embodiment, the upper 2 includes a middle bottom 21 (see Fig. 4) forming a lower portion of the upper 2. An insole (not illustrated) may be attached to the upper surface side of the middle bottom 21.
The upper 2 is formed with a foot insertion opening portion 22 for inserting a foot of the wearer, and an instep opening portion 23 extending forward (to the toe side of the wearer of the shoe 9) from the foot insertion opening portion 22. The instep opening portion 23 is closed from the back side by a tongue 24. The tongue 24 covers a range from a front portion of an ankle of the wearer to an instep. A shoelace 25 passing through a plurality of eyelet holes intersects above the tongue 24. Due to downward pressing force accompanying tightening of the shoelace 25, the tongue 24 fits a foot of the wearer.
Fig. 2 is a perspective view of the sole 1. Fig. 3 is a plan view of the sole 1. In Fig. 3, a shoe center SC and a heel center HC are indicated by a one-dot chain line. The shoe center SC is not limited to a center line of the shoe 9, and may be a straight line connecting the center of a calcaneus of the wearer of the shoe 9 and a space between a first toe and a second toe. With the shoe center SC as a reference, the first toe side (right side in Fig. 3) of a foot is the medial foot side, and a fifth toe side (left side in Fig. 3) of the foot is the lateral foot side. In a sole for a right foot, the medial foot side and the lateral foot side are laterally inverted. The heel center HC is a straight line connecting the center of a calcaneus of the wearer of the shoe 9 and a space between a third toe and a fourth toe.
The sole 1 includes a cup-shaped sole main body portion 10. In the present embodiment, the sole main body portion 10 includes a forefoot region Rf that is a region on the toe side of the wearer of the shoe 9, a hindfoot region Rb that is a region on the heel side of the wearer of the shoe 9, and a midfoot region Rm that is a region between the forefoot region Rf and the hindfoot region Rb. The sole main body portion 10 continuously extends from the forefoot region Rf to the hindfoot region Rb via the midfoot region Rm without being divided in the middle.
When a length obtained as a distance from one end to another end in a length direction of the sole main body portion 10 is L, the forefoot region Rf may be, for example, a region located in a range of 0% to 40% of the length L from a front end portion toward a rear end portion of the sole main body portion 10. The hindfoot region Rb may be, for example, a region located in a range of 80% to 100% of the length L from a front end portion toward a rear end portion of the sole main body portion 10.
The sole main body portion 10 includes a flat plate-shaped bottom portion 11 and a wall portion 12 rising upward from an outer edge of the bottom portion 11. The bottom portion 11 and the wall portion 12 are integrally formed by a single member. The bottom portion 11 extends along a front-rear direction (vertical direction in Fig. 3) which is also the length direction of the sole main body portion 10. The wall portion 12 extends continuously along an outer edge of the bottom portion 11 and has an annular shape in plan view. The wall portion 12 includes forefoot side wall portion 12f located in the forefoot region Rf, a hindfoot side wall portion 12b located in the hindfoot region Rb, and a midfoot side wall portion 12m located in the midfoot region Rm.
The sole 1 of the present embodiment is an outsole in which a lower surface of the sole main body portion 10 serves as a ground contact surface. The sole main body portion 10 included in the sole 1 as an outsole is preferably made from rubber from the viewpoint of securing wear resistance and grip performance. For example, rubber obtained by blending a plasticizer, a reinforcing agent, a crosslinking agent, or the like as an accessory component with a rubber material as a main component is used. As the rubber material, butadiene rubber is suitably used, but not the rubber material is limited to this, and for example, urethane rubber, silicone rubber, or the like can also be used. A tread pattern with irregularities formed by a groove or the like may be provided on a lower surface of the sole main body portion 10.
Fig. 4 is a cross-sectional view taken along line IV-IV of Fig. 3 passing through the shoe center SC. A flat surface P corresponds to the ground on which the shoe 9 is placed. Fig. 5A is a side view as viewed from the lateral foot side, Fig. 5B is a rear view, and Fig. 5C is a side view as viewed from the medial foot side of the hindfoot region Rb of the sole main body portion 10. Fig. 6 is a cross-sectional view taken along line VI-VI of Fig. 3 perpendicular to the heel center HC. Fig. 7 is a cross-sectional view taken along line VII-VII of Fig. 3 perpendicular to the heel center HC. Fig. 8 is a cross-sectional view taken along line VIII-VIII of Fig. 3 perpendicular to the shoe center SC.
An inner groove 31 extending along an outer edge of the bottom portion 11 is formed on an inner peripheral surface 12X of the wall portion 12, and an outer groove 32 extending along an outer edge of the bottom portion 11 is formed on an outer peripheral surface 12Y of the wall portion 12. By the above, the wall portion 12 is easily bent when a load from a foot of the wearer acts in normal walking motion, and deformation of the sole 1 is promoted to improve cushioning property. In addition, reduction in weight of the sole 1 can be achieved by lightening of the wall portion 12 with the inner groove 31 and the outer groove 32. Therefore, in the present embodiment, a coat style shoe that provides comfortable cushioning property while having a thin bottom is provided.
As illustrated in Fig. 6, the inner groove 31 is formed at a position away downward from an upper end 12t of the wall portion 12. The wall portion 12 has a maximum thickness portion 12w having maximum thickness in a state where the outer groove 32 is filled, and the inner groove 31 is formed below the maximum thickness portion 12w. The inner peripheral surface 12X extends downward from the upper end 12t and reaches the maximum thickness portion 12w via a curved portion 12c having an arcuate cross section. The curved portion 12c changes a height position of the curved portion 12c (position in the vertical direction) along the front-rear direction, and is separated upward from an upper surface of the bottom portion 11 in the hindfoot region Rb and the midfoot region Rm (see Figs. 6 and 7), but is smoothly connected to an upper surface of the bottom portion 11 in the forefoot region Rf (see Fig. 8). The inner groove 31 is terminated at a position where the curved portion 12c starts to be connected to an upper surface of the bottom portion 11 (see Fig. 2).
As illustrated in Fig. 6, in the present embodiment, when the wall portion 12 is viewed in a cross section along the vertical direction, the inner groove 31 and the outer groove 32 are arranged so as to have a portion overlapping in the horizontal direction with a facing region 12r of the wall portion 12 interposed between them. In a main part enlarged view of Fig. 6, the facing region 12r of the wall portion 12 where the inner groove 31 and the outer groove 32 face each other is hatched, and the inner groove 31 and the outer groove 32 overlap each other in the horizontal direction in the region. According to such a positional relationship between the inner groove 31 and the outer groove 32, ease of bending of the wall portion 12 can be enhanced in an excellent manner, and cushioning property can be effectively improved.
The inner groove 31 is formed as a groove that is recessed toward the outer peripheral surface 12Y and does not penetrate the wall portion 12. The outer groove 32 is formed as a groove that is recessed toward the inner peripheral surface 12X and does not penetrate the wall portion 12. At least one of the inner groove 31 and the outer groove 32 preferably has a rounded cross-sectional shape as illustrated in Fig. 6, and more preferably has a cross-sectional shape curved in an arc shape. By the above, stress concentration on a groove inner surface when the wall portion 12 is bent and deformed is suppressed, and an effect of enhancing durability is obtained. Further, when the sole main body portion 10 is molded, demolding property when the sole main body portion 10 is removed from a mold is excellent. In the present embodiment, both the inner groove 31 and the outer groove 32 have a cross-sectional shape curved in an arc shape.
As in the present embodiment, a deepest portion 31d of the inner groove 31 in the facing region 12r is preferably displaced in the vertical direction with respect to a deepest portion 32d of the outer groove 32 in the facing region 12r. According to such a configuration, thickness of the wall portion 12 can be prevented from becoming too small locally while flexibility of the wall portion 12 is increased, so that appropriate rigidity can be easily secured in the wall portion 12. In the present embodiment, the deepest portion 31d is displaced downward with respect to the deepest portion 32d, but conversely, the deepest portion 31d may be displaced upward, or height positions of them may coincide with each other.
In the present embodiment, the facing region 12r of the wall portion 12 extends by being inclined toward the shoe center SC side toward the upper side. According to such a configuration, the inner groove 31 and the outer groove 32 increase flexibility of the wall portion 12 and easily resist a load from a foot of the wearer, so that an effect of suppressing excessive falling of the wall portion 12 that causes the wearer to feel a sense of discomfort or unease can be obtained.
A cross-sectional shape of the inner groove 31 is curved in an arc shape deformed in a manner that depth increases toward the lower side, and a cross-sectional shape of the outer groove 32 is curved in an arc shape deformed in a manner that depth increases toward the upper side. This is advantageous in that the inner groove 31 and the outer groove 32 are caused to overlap each other in the horizontal direction, a rounded cross-sectional shape is applied to the inner groove 31 and the outer groove 32, and the deepest portions 31d and 32d are displaced in the vertical direction. Further, according to such a cross-sectional shape of the inner groove 31, when the sole main body portion 10 is molded, a mold portion for molding the inner groove 31 easily comes out of the inner groove 31 by upward relative movement, so that an effect of enhancing demolding property is obtained.
A cross-sectional shape of the inner groove 31 and the outer groove 32 is not particularly limited. Therefore, for example, a shape obtained by vertically inverting a shape of the present embodiment, a simple arc shape, a polygonal shape with a rounded corner, or the like may be used.
Depth D31 of the inner groove 31 is not particularly limited, but is preferably 0.1 mm or more, and more preferably 1.0 mm or more from the viewpoint of improving cushioning property. Further, the depth D31 is preferably 20 mm or less, and more preferably 10 mm or less, from the viewpoint of suppressing excessive falling of the wall portion 12.
Depth D32 of the outer groove 32 is not particularly limited, but is preferably 1.0 mm or more, and more preferably 3.0 mm or more from the viewpoint of improving cushioning property. Further, the depth D32 is preferably 20 mm or less, and more preferably 10 mm or less, from the viewpoint of suppressing excessive falling of the wall portion 12.
From the viewpoint of securing appropriate rigidity in the wall portion 12, minimum thickness T12r in the facing region 12r is preferably 1.0 mm or more, and more preferably 2.5 mm or more.
In a case where depth of the outer groove 32 is changed along an extending direction, a maximum value of depth D32 of the outer groove 32 is used. From the viewpoint of improving cushioning property at the time of heel contact in normal walking motion, the depth D32 is preferably depth measured in the hindfoot side wall portion 12b. The depth D31 of the inner groove 31 is measured at a position corresponding to a measurement position of the depth D32 of the outer groove 32, and preferably has a maximum value in a case where the inner groove 31 changes in depth along an extending direction.
In order to enhance comfort in normal walking motion, improving cushioning property particularly at the time of heel contact (at the start of landing) is effective. From such a viewpoint, the inner groove 31 and the outer groove 32 are preferably formed at least in the hindfoot side wall portion 12b.
Sections Z31 and Z32 illustrated in Fig. 3 represent sections in which the inner groove 31 and the outer groove 32 are formed, respectively. The hindfoot side wall portion 12b has a U-shape extending from the medial foot side to the lateral foot side through a rear end portion of the sole main body portion 10 in plan view, and the outer groove 32 formed in the hindfoot side wall portion 12b includes a portion having a U-shape in plan view along the U-shape of the hindfoot side wall portion 12b. According to such a configuration, cushioning property at the time of heel contact in normal walking motion can be effectively improved.
The inner groove 31 formed in the hindfoot side wall portion 12b includes a portion having a U-shape in plan view along a U-shape of the hindfoot side wall portion 12b. The section Z31 in which the inner groove 31 is formed extends in a range including the section Z32 in which the outer groove 32 is formed. Therefore, in the section Z32 where the outer groove 32 is formed, the inner groove 31 is formed over the entire area. In the present embodiment, a positional relationship (see Fig. 6) in which the inner groove 31 and the outer groove 32 have a portion overlapping in the horizontal direction with the facing region 12r of the wall portion 12 interposed between them is established over the entire section Z32.
In the present embodiment, each of the inner groove 31 and the outer groove 32 is a single groove extending continuously, but the present invention is not limited to this, and the inner groove 31 and the outer groove 32 may be interrupted in the middle. Therefore, for example, it is possible to have a form in which both or one of the inner groove 31 and the outer groove 32 is formed only on a rear end portion of the hindfoot side wall portion 12b or a form in which both or one of them are formed only on both sides (medial foot side and lateral foot side).
As illustrated in Figs. 5A and 5C, a groove width of the outer groove 32 gradually decreases toward an end portion of the outer groove 32. By the above, a rapid change in flexibility of the wall portion 12 around an end portion of the outer groove 32 is suppressed. Further, in the present embodiment, since the outer groove 32 has not only a groove width but also depth gradually decreasing toward an end portion of the outer groove 32, the above effect is enhanced.
In the present embodiment, a length of the outer groove 32 formed in the midfoot side wall portion 12m is reduced from the viewpoint of sufficiently securing stability of walking motion while improving cushioning property at the time of heel contact in normal walking motion. In such a case, the outer groove 32 is preferably formed so as to be within a range of 0% to 30% of the length L from a rear end portion toward a front end portion of the sole main body portion 10. Further, an end portion of the outer groove 32 is preferably located further on the rear side (on the heel side of the wearer of the shoe 9) than an end portion of the inner groove 31.
In the present embodiment, the inner groove 31 formed in the hindfoot side wall portion 12b has substantially the same depth on the medial foot side and the lateral foot side. However, the present invention is not limited to this, and the inner groove 31 may have different depths on the medial foot side and the lateral foot side. For example, in a cross section perpendicular to the heel center HC, if depth of the inner groove 31 is larger on the lateral foot side than on the medial foot side, the lateral foot side of the sole 1 is relatively easily deformed, and overpronation during walking can be reduced. On the other hand, with a configuration in which depth of the inner groove 31 is smaller on the lateral foot side than on the medial foot side, the medial foot side of the sole 1 is relatively easily deformed, which is useful to achieve the medial center of gravity (a state in which the center of gravity is closer to the medial foot side) that is advantageous in a skateboarding competition or the like.
The sole 1 further includes a flat-plate-shaped buffer member 13 arranged on the upper surface side of the bottom portion 11. The buffer member 13 has a side portion 13s arranged to face the inner groove 31. The buffer member 13 alleviates an impact applied to a foot (in particular, a heel) of the wearer. Since the buffer member 13 is formed of a soft member having a small elastic modulus, the buffer member 13 elastically deforms relatively easily when receiving a compressive load and has excellent shock absorption property. The buffer member 13 preferably has a lower hardness (for example, Asker C hardness) than the sole main body portion 10. For example, a material having the Asker C hardness of 30 or more and 90 or less is suitably used for the buffer member 13. The Asker C hardness is determined in accordance with JISK7312:1996.
The buffer member 13 preferably has an appropriate strength and excellent shock absorption property. From the viewpoint, for the buffer member 13, for example, a resin foam material obtained by blending a foaming agent, a crosslinking agent, or the like as an accessory component with a resin material as a main component is used. As the resin material, for example, ethylene-vinyl acetate copolymer (EVA), polyolefin resin, thermoplastic polyurethane, thermoplastic polyamide-based elastomer (TPA, TPAE), or thermoplastic polyester-based elastomer is suitably used. Alternatively, a rubber foam material obtained by blending a plasticizer, a foaming agent, a reinforcing agent, a crosslinking agent, or the like as an accessory component with a rubber material as a main component may be used. As the rubber material, for example, butadiene rubber is suitably used.
The buffer member 13 is formed of a member separate from the sole main body portion 10, and is attached to the sole main body portion 10 in a bonded or non-bonded state. The buffer member 13 is formed in a plate shape extending in the front-rear direction. The buffer member 13 has a plan view shape corresponding to the bottom portion 11, but extends forward from a rear end portion and terminates in the midfoot region Rm. The inner groove 31 extends to the vicinity of a front end portion of the buffer member 13. Thickness of the buffer member 13 gradually decreases from the middle toward a front end portion in the front-rear direction of the buffer member 13, and is substantially constant in the hindfoot region Rb. An upper surface of the buffer member 13 is arranged at a height position substantially corresponding to the curved portion 12c of the inner peripheral surface 12X (see Figs. 6 and 7).
In the present embodiment, as illustrated in Figs. 6 and 7, a gap is formed between the side portion 13s and the inner groove 31. By the above, an escape space when the buffer member 13 receiving a compressive load from a foot of the wearer is bulged and deformed toward the wall portion 12 is provided, so that deformation of the buffer member 13 can be promoted to further improve cushioning property. As described above, the inner groove 31 promotes not only bending deformation of the wall portion 12 in cooperation with the outer groove 32, but also deformation of the buffer member 13, and all of them contribute to improvement of cushioning property. The side portion 13s of the present embodiment is formed by a flat surface parallel to the vertical direction, but is not limited to this.
In the present embodiment, a groove inner surface of the inner groove 31 is smoothly connected to an upper surface of the bottom portion 11. Such a configuration is convenient for causing the inner groove 31 to function as an escape space when the buffer member 13 is bulged and deformed.
The wall portion 12 in which the inner groove 31 and the outer groove 32 are formed contributes to improvement of cushioning property due to ease of bending of the wall portion 12, but when a relatively large load is applied and excessive falling occurs, the wearer may feel a sense of discomfort or unease. Fig. 9 is a cross-sectional view illustrating a variation that may be a preventive measure against the above, and corresponds to Fig. 6 (a cross section taken along line VI-VI in Fig. 3). In this variation, the side portion 13s of the buffer member 13 projects toward the wall portion 12 and can enter the inner groove 31. As the side portion 13s enters a part or the whole of the inner groove 31 in this manner, an effect of preventing excessive falling of the wall portion 12 is obtained.
Volume of the side portion 13s entering the inner groove 31 may be substantially the same on the medial foot side and the lateral foot side, but may be different. In the example of Fig. 9A, volume of the side portion 13s entering the inner groove 31 is smaller on the lateral foot side (left side in Fig. 9) than on the medial foot side (right side in Fig. 9). According to such a configuration, since the lateral foot side of the buffer member 13 is relatively easily deformed, overpronation during walking can be reduced. In the example of Fig. 9B, volume of the side portion 13s entering the inner groove 31 is larger on the lateral foot side than on the medial foot side. According to such a configuration, the medial foot side of the buffer member 13 is relatively easily deformed, which is useful for realizing the medial center of gravity.
Since the buffer member 13 is formed of a relatively soft member, in the structure in which the side portion 13s enters the inner groove 31 as described above, an effect of improving cushioning property by the inner groove 31 and the outer groove 32 is achieved. Fig. 9 illustrates an example in which the side portion 13s enters the inner groove 31 formed in the hindfoot side wall portion 12b. Alternatively or in addition, the side portion 13s may be configured to enter the inner groove 31 formed in the midfoot side wall portion 12m or the forefoot side wall portion 12f. In this case, as a matter of course, the inner groove 31 is formed in the midfoot side wall portion 12m and the forefoot side wall portion 12f, and the buffer member 13 has a side portion 31s facing the inner groove 31.
As illustrated in Figs. 10 to 16, the buffer member 13 may be provided with a cutout portion 14. According to such a configuration, flexibility of the buffer member 13 is increased, and the cutout portion 14 functions as an escape space when the buffer member 13 receiving a compressive load from a foot of the wearer is deformed, so that cushioning property can be further improved. In addition, reduction in weight of the sole 1 can be achieved. As specifically described below, the cutout portion 14 can be formed by, for example, a hole, a recessed portion, a notch, a groove, and the like, and these may be used in combination.
In the example illustrated in Fig. 10, the buffer member 13 is provided with a plurality of through holes 14A penetrating in the vertical direction over the entire surface. According to such a configuration, an effect of improving cushioning property can be obtained over the entire region of the buffer member 13 in walking motion in general. The through holes 14A are preferably provided so that arrangement density of the through holes 14A is substantially uniform over the entire surface of the buffer member 13. The through hole 14A has a circular shape in plan view, but may have another shape. Instead of the through hole 14A, a plurality of non-penetrating recessed portions (including dimples) can be provided. The recessed portion is provided in at least one of an upper surface and a lower surface of the buffer member 13. The through hole 14A and the recessed portion may be mixed. Further, a plurality of the through holes 14A may be provided in a partial region instead of the entire surface of the buffer member 13.
In the example illustrated in Fig. 11, the buffer member 13 is provided with a plurality of notches 14B obtained by notching an edge portion of the buffer member 13. The notch 14B is formed by notching an edge portion of a heel peripheral portion of the buffer member 13. According to such a configuration, an effect of improving cushioning property at a heel peripheral portion of the buffer member 13 at the time of heel contact in walking motion can be obtained. The notch 14B has a D-shape in plan view, but may have another shape.
When a width obtained as a distance from one end to another end in a width direction (left-right direction in Fig. 12) of the sole main body portion 10 is W, a central region CA illustrated in Figs. 12 to 16 is a region in a range of 0.25W to 0.75W from the one end to the another end. In other words, the central region CA is a region extending in a range of 0.50W (range of 50% of the width W) with the width center of the sole main body portion 10 as the center. A center line CL of movement of the center of gravity in normal walking motion is located in the central region CA of the sole main body portion 10. Note that a width direction of the sole main body portion 10 is a direction perpendicular to the front-rear direction which is also a length direction of the sole main body portion 10.
In the example illustrated in Fig. 12, the buffer member 13 is divided into right and left portions in the central region CA along the front-rear direction of the sole main body portion 10. A through groove 14C penetrating in the vertical direction is formed in the central region CA. The through groove 14C extends forward from a rear end portion of the buffer member 13 and reaches a front end portion. Width of the through groove 14C is, for example, 0.1W to 0.25W. According to such a configuration, in walking motion in general, an effect of improving cushioning property can be obtained in the central region CA (particularly, in the vicinity of the through groove 14C). Furthermore, since the center line CL of movement of the center of gravity is located in the central region CA, the through groove 14C formed in the central region CA and the center line CL of movement of the center of gravity easily overlap each other, and variation in movement of the center of gravity during walking can be reduced and stable walking can be promoted.
In the example illustrated in Fig. 13, at least one of an upper surface and a lower surface of the buffer member 13 is provided with a longitudinal groove 14D extending in the central region CA along the front-rear direction of the sole main body portion 10. The longitudinal groove 14D extends forward from a rear end portion of the buffer member 13 and longitudinally extends through the hindfoot region Rb, but terminates halfway without reaching a front end portion of the buffer member 13. According to such a configuration, an effect of improving cushioning property is obtained at least at the time of heel contact in walking motion, and variation in movement of the center of gravity during walking can be reduced and stable walking can be promoted. The longitudinal groove 14D is a non-penetrating groove, but may be a penetrating groove penetrating vertically.
In the example illustrated in Fig. 14, at least one of an upper surface and a lower surface of the buffer member 13 is provided with a longitudinal groove 14E extending in the central region CA along the front-rear direction of the sole main body portion 10. Since this aspect has the same configuration and operation as the example illustrated in Fig. 13 except that the longitudinal groove 14E intermittently extends, redundant description will be omitted.
In the example illustrated in Fig. 15, the buffer member 13 is provided with a plurality of through holes 14F penetrating in the vertical direction, and the through holes 14F are arranged linearly in the central region CA along the front-rear direction of the sole main body portion 10. An arrangement group of the linear through holes 14F extends forward from a rear end portion of the buffer member 13 and longitudinally extends through the hindfoot region Rb, but terminates halfway without reaching a front end portion of the buffer member 13. According to such a configuration, an effect of improving cushioning property is obtained at least at the time of heel contact in walking motion, and variation in movement of the center of gravity during walking can be reduced and stable walking can be promoted. Instead of the through hole 14F, a plurality of non-penetrating recessed portions (including dimples) can be provided, and these may be mixed.
In the example illustrated in Fig. 16, the buffer member 13 is provided with a plurality of through holes 14G penetrating in the vertical direction, and the through holes 14G are arranged linearly in the central region CA along the front-rear direction of the sole main body portion 10. Since this aspect has the same configuration and operation as the example illustrated in Fig. 15 except that the through holes 14G having different sizes are arranged in a line, redundant description will be omitted.
In the example illustrated in Figs. 13 to 16, the cutout portions 14 are formed to be wider toward a rear end portion of the buffer member 13. Such a configuration is convenient for improving cushioning property at a heel peripheral portion of the buffer member 13 at the time of heel contact in walking motion.
In the present embodiment, the cutout portion 14 is a void, but the present invention is not limited to this. For example, the configuration may be such that a low rigidity material is embedded in the cutout portion 14, and in such a case as well, an effect of the cutout portion 14 described above is achieved based on a difference in rigidity from the buffer member 13. As the low rigidity material, a foam material, a gel material, a rubber material, or the like having hardness (for example, Asker C hardness) lower than that of the buffer member 13 is suitably used.
Unless otherwise specified, a shape, dimension, a positional relationship, and the like regarding the sole 1 and the shoe 9 are based on a no-load state (a state in which the wearer does not wear the shoe 9 and a load from a foot of the wearer does not act) in which no external force acts.
In the present embodiment, an example in which the sole 1 is an outsole arranged at the lowermost side of the shoe 9 is described, but the present invention is not limited to this. For example, the configuration may be such that a sole is a midsole arranged above an outsole, and a part or whole of a lower surface of a sole main body portion of the sole (midsole) is covered by the outsole.
It is understood by those skilled in the art that the foregoing embodiment is a specific example of aspects below.

[1] A sole of the present disclosure is a sole constituting a part of a shoe. The sole has a cup-shaped sole main body portion. The sole main body portion includes a flat plate-shaped bottom portion and a wall portion rising upward from an outer edge of the bottom portion. An inner groove extending along an outer edge of the bottom portion is formed on an inner peripheral surface of the wall portion, and an outer groove extending along an outer edge of the bottom portion is formed on an outer peripheral surface of the wall portion.
According to such a configuration, the wall portion is easily bent when a load from a foot of the wearer acts in normal walking motion, and deformation of the sole can be promoted and cushioning property is improved. Further, in addition, reduction in weight of the sole can be achieved by lightening a wall portion with an inner groove and an outer groove. Therefore, improvement in cushioning property and reduction in weight can be achieved.
[2] In the sole of the above [1], the inner groove and the outer groove may be arranged so as to have a portion where the inner groove and the outer groove overlap each other in a horizontal direction with a facing region of the wall portion interposed therebetween when the wall portion is viewed in a cross section along a vertical direction. By the above, ease of bending of the wall portion can be enhanced in an excellent manner, and cushioning property can be effectively improved.
[3] In the sole of the above [1] or [2], at least one of the inner groove and the outer groove may have a cross-sectional shape curved in an arc shape. By the above, stress concentration on a groove inner surface when the wall portion is bent and deformed is suppressed, and an effect of enhancing durability is obtained.
[4] In the sole of the above [2], a deepest portion of the inner groove in the facing region may be displaced in a vertical direction from a deepest portion of the outer groove in the facing region. According to such a configuration, thickness of the wall portion can be prevented from becoming too small locally while flexibility of the wall portion is increased, and thus, appropriate rigidity in the wall portion can be easily secured.
[5] In the sole of any one of the above [1] to [4], the sole main body portion may include a forefoot region which is a region on a toe side of a wearer of the shoe, a hindfoot region which is a region on a heel side of the wearer of the shoe, and a midfoot region which is a region between the forefoot region and the hindfoot region. The wall portion may include a forefoot side wall portion located in the forefoot region, a hindfoot side wall portion located in the hindfoot region, and a midfoot side wall portion located in the midfoot region. The inner groove and the outer groove may be formed in at least the hindfoot side wall portion. By the above, cushioning property at the time of heel contact can be effectively improved.
[6] In the sole of the above [5], the hindfoot side wall portion may have a U-shape extending from a medial foot side to a lateral foot side through a rear end portion of the sole main body portion in plan view. The outer groove formed in the hindfoot side wall portion may include a portion having a U-shape in plan view along a U-shape of the hindfoot side wall portion. By the above, cushioning property at the time of heel contact can be effectively improved.
[7] In the sole of the above [6], the inner groove formed in the hindfoot side wall portion may include a portion having a U-shape in plan view along a U-shape of the hindfoot side wall portion. By the above, cushioning property at the time of heel contact can be effectively improved.
[8] In the sole of any one of the above [5] to [7], the inner groove formed in the hindfoot side wall portion may have different depths on a medial foot side and on a lateral foot side. According to such a configuration, the lateral foot side or the medial foot side of the sole is relatively easily deformed, which is useful for suppressing overpronation and realizing the medial center of gravity.
[9] In the sole of any one of the above [1] to [8], the outer groove may have a groove width gradually decreasing toward an end portion thereof. By the above, a rapid change in flexibility of the wall portion around an end portion of the outer groove is suppressed.
[10] In the sole of any one of the above [1] to [9], the sole further may include a flat plate-shaped buffer member arranged on an upper surface side of the bottom portion. The buffer member may have a side portion arranged to face the inner groove. As the sole includes the buffer member, a further improving effect of cushioning property can be obtained.
[11] In the sole of the above [10], a gap may be formed between the side portion and the inner groove. According to such a configuration, since an escape space when the buffer member is bulged and deformed toward the wall portion is provided, deformation of the buffer member can be promoted to further improve cushioning property.
[12] In the sole of the above [10], the side portion may project toward the wall portion and be configured to be able to enter the inner groove. According to such a configuration, an effect of suppressing excessive falling of the wall portion can be obtained.
[13] In the sole of any one of the above [10] to [12], the buffer member may be provided with a plurality of through holes penetrating in a vertical direction or a plurality of non-penetrating recessed portions over an entire surface. According to such a configuration, reduction in weight can be achieved while cushioning property by the buffer member is further improved.
[14] In the sole of any one of the above [10] to [13], the buffer member may be provided with a plurality of notches obtained by notching an edge portion of the buffer member. According to such a configuration, reduction in weight can be achieved while cushioning property by the buffer member is further improved.
[15] In the sole of any one of the above [10] to [14], when width obtained as a distance from one end to another end in a width direction of the sole main body portion is W, and a range of 0.25W to 0.75W from the one end to the another end is a central region of the sole main body portion, the buffer member may be divided into right and left portions in the central region along a front-rear direction of the sole main body portion. According to such a configuration, reduction in weight can be achieved while cushioning property by the buffer member is further improved. Furthermore, variation in movement of the center of gravity during walking can be reduced and stable walking can be promoted.
[16] In the sole of any one of the above [10] to [15], when width obtained as a distance from one end to another end in a width direction of the sole main body portion is W, and a range of 0.25W to 0.75W from the one end to the another end is a central region of the sole main body portion, at least one of an upper surface and a lower surface of the buffer member may be provided with a longitudinal groove extending in the central region along a front-rear direction of the sole main body portion. According to such a configuration, reduction in weight can be achieved while cushioning property by the buffer member is further improved. Furthermore, variation in movement of the center of gravity during walking can be reduced and stable walking can be promoted.
[17] In the sole of any one of the above [10] to [16], when width obtained as a distance from one end to another end in a width direction of the sole main body portion is W, and a range of 0.25W to 0.75W from the one end to the another end is a central region of the sole main body portion, the buffer member may be provided with a plurality of through holes penetrating in a vertical direction or a plurality of non-penetrating recessed portions. The through holes or the non-penetrating recessed portions may be arranged linearly in the central region along a front-rear direction of the sole main body portion. According to such a configuration, reduction in weight can be achieved while cushioning property by the buffer member is further improved. Furthermore, variation in movement of the center of gravity during walking can be reduced and stable walking can be promoted.
[18] In the sole of any one of the above [1] to [9], the sole further may include a flat plate-shaped buffer member arranged on an upper surface side of the bottom portion. The buffer member may be provided with a plurality of through holes penetrating in a vertical direction or a plurality of non-penetrating recessed portions over an entire surface. Further, since the through hole or the recessed portion as described above is provided, reduction in weight can be achieved while cushioning property is further improved by the buffer member.
[19] A shoe of the present disclosure has the sole of any one of the above [1] to [18], and an upper arranged above the sole. By providing the sole as described above, cushioning property can be improved and reduction in weight can be achieved.
[20] In the shoe of the above [19], the sole may be an outsole in which a lower surface of the sole main body portion serves as a ground contact surface. According to such a configuration, cushioning property can be improved and reduction in weight of a shoe including the sole as an outsole.

Although the embodiment of the sole and the shoe according to the present disclosure have been described with reference to the drawings, it should be considered that the specific configuration is not limited to this embodiment. The scope of the present invention is indicated not only by the description of the above embodiment but also by the claims, and further includes meanings equivalent to the claims and all modifications within the scope of the claims.
The sole and shoe according to the present disclosure are not limited to the above-described embodiment at all, and are not limited to the above-described actions and effects. The sole and shoe according to the present disclosure can be variously improved and changed without departing from the gist thereof. In addition, the configurations employed in the above-described embodiment can be employed in any combination.
[Reference 1] to [Reference 5] below are indicated as reference examples relating to the sole and the shoe having the configuration in the present disclosure.

[Reference 1]

A sole constituting a part of a shoe, the sole comprising:

a cup-shaped sole main body portion, wherein
the sole main body portion includes a flat plate-shaped bottom portion and a wall portion rising upward from an outer edge of the bottom portion,
an inner groove extending along an outer edge of the bottom portion is formed on an inner peripheral surface of the wall portion,
the sole further comprises a flat plate-shaped buffer member arranged on an upper surface side of the bottom portion,
the buffer member has a side portion arranged to face the inner groove, and
a gap is formed between the side portion and the inner groove.

According to such a configuration, since an escape space when the buffer member is bulged and deformed toward the wall portion is provided, deformation of the buffer member can be promoted to further improve cushioning property. A characteristic configuration of the sole of [Reference 1] above is seen in Fig. 6, for example. The configuration described in the above embodiment can be applied to the sole of [Reference 1] above without any particular limitation without departing from the gist of the configuration. The sole of [Reference 1] above is not limited to a configuration in which the outer groove is formed on an outer peripheral surface of the wall portion.

[Reference 2]

A sole constituting a part of a shoe, the sole comprising:

a cup-shaped sole main body portion, wherein
the sole main body portion includes a flat plate-shaped bottom portion and a wall portion rising upward from an outer edge of the bottom portion,
an inner groove extending along an outer edge of the bottom portion is formed on an inner peripheral surface of the wall portion,
the sole further comprises a flat plate-shaped buffer member arranged on an upper surface side of the bottom portion,
the buffer member has a side portion arranged to face the inner groove, and
the side portion projects toward the wall portion and is configured to be able to enter the inner groove.

According to such a configuration, an effect of suppressing excessive falling of the wall portion due to the inner groove can be obtained. A characteristic configuration of the sole of [Reference 2] above is seen in Fig. 9, for example. The configuration described in the above embodiment can be applied to the sole of [Reference 2] above without any particular limitation without departing from the gist of the configuration. The sole of [Reference 2] above is not limited to a configuration in which the outer groove is formed on an outer peripheral surface of the wall portion.

[Reference 3]

A sole constituting a part of a shoe, the sole comprising:

a cup-shaped sole main body portion, wherein
the sole main body portion includes a flat plate-shaped bottom portion and a wall portion rising upward from an outer edge of the bottom portion,
the sole further comprises a flat plate-shaped buffer member arranged on the upper surface side of the bottom portion, and
the buffer member is provided with a cutout portion.

According to such a configuration, flexibility of the buffer member is increased, and the cutout portion functions as an escape space when the buffer member is deformed by receiving a compressive load, so that cushioning property can be further improved. In addition, reduction in weight of the sole can be achieved. A characteristic configuration of the sole of [Reference 3] above is seen in Figs. 10 to 16, for example. The configuration described in the above embodiment can be applied to the sole of [Reference 3] above without any particular limitation without departing from the gist of the configuration. The sole of [Reference 3] above is not limited to a configuration in which the inner groove and the outer groove are formed in the wall portion.

[Reference 4]

A sole constituting a part of a shoe, the sole comprising:

a cup-shaped sole main body portion, wherein
the sole main body portion includes a flat plate-shaped bottom portion and a wall portion rising upward from an outer edge of the bottom portion,
the sole further comprises a flat plate-shaped buffer member arranged on the upper surface side of the bottom portion, and
the buffer member is provided with a plurality of through holes penetrating in a vertical direction or a plurality of non-penetrating recessed portions over an entire surface.

According to such a configuration, an effect of improving cushioning property by the buffer member can be obtained. Further, since the through hole or the recessed portion as described above is provided, reduction in weight can be achieved while cushioning property is further improved by the buffer member. A characteristic configuration of the sole of [Reference 4] above is seen in Fig. 10, for example. The configuration described in the above embodiment can be applied to the sole of [Reference 4] above without any particular limitation without departing from the gist of the configuration. The sole of [Reference 4] above is not limited to a configuration in which the inner groove and the outer groove are formed in the wall portion.

[Reference 5]

A shoe comprising: the sole of any one of the above [Reference 1] to [Reference 4]; and an upper arranged above the sole. According to such a configuration, the actions and effects of including the sole described above is obtained.
1 sole, 2 upper, 9 shoe, 10 sole main body portion, 11 bottom portion, 12 wall portion, 12b hindfoot side wall portion, 12f forefoot side wall portion, 12m midfoot side wall portion, 12r facing region, 12X inner peripheral surface, 12Y outer peripheral surface, 13 buffer member, 13s side portion, 14 cutout portion, 14A through hole, 14B notch, 14C through groove, 14D longitudinal groove, 14E longitudinal groove, 14F through hole, 14G through hole, 31 inner groove, 31d deepest portion, 32 outer groove, 32d deepest portion, Rf forefoot region, Rb hindfoot region, Rm midfoot region

Claims

A sole constituting a part of a shoe, the sole comprising:
a cup-shaped sole main body portion, wherein

the sole main body portion includes a flat plate-shaped bottom portion and a wall portion rising upward from an outer edge of the bottom portion, and

an inner groove extending along an outer edge of the bottom portion is formed on an inner peripheral surface of the wall portion, and an outer groove extending along an outer edge of the bottom portion is formed on an outer peripheral surface of the wall portion.
The sole according to claim 1, wherein the inner groove and the outer groove are arranged so as to have a portion where the inner groove and the outer groove overlap each other in a horizontal direction with a facing region of the wall portion interposed therebetween when the wall portion is viewed in a cross section along a vertical direction.
The sole according to claim 1 or 2, wherein at least one of the inner groove and the outer groove has a cross-sectional shape curved in an arc shape.
The sole according to claim 2, wherein a deepest portion of the inner groove in the facing region is displaced in a vertical direction from a deepest portion of the outer groove in the facing region.
The sole according to any one of claims 1 to 4, wherein
the sole main body portion includes a forefoot region which is a region on a toe side of a wearer of the shoe, a hindfoot region which is a region on a heel side of the wearer of the shoe, and a midfoot region which is a region between the forefoot region and the hindfoot region,

the wall portion includes a forefoot side wall portion located in the forefoot region, a hindfoot side wall portion located in the hindfoot region, and a midfoot side wall portion located in the midfoot region, and

the inner groove and the outer groove are formed in at least the hindfoot side wall portion.
The sole according to claim 5, wherein
the hindfoot side wall portion has a U-shape extending from a medial foot side to a lateral foot side through a rear end portion of the sole main body portion in plan view, and

the outer groove formed in the hindfoot side wall portion includes a portion having a U-shape in plan view along a U-shape of the hindfoot side wall portion.
The sole according to claim 6, wherein the inner groove formed in the hindfoot side wall portion includes a portion having a U-shape in plan view along a U-shape of the hindfoot side wall portion.
The sole according to any one of claims 5 to 7, wherein the inner groove formed in the hindfoot side wall portion has different depths on a medial foot side and on a lateral foot side.
The sole according to any one of claims 1 to 8, wherein the outer groove has a groove width gradually decreasing toward an end portion thereof.
The sole according to any one of claims 1 to 9, further comprising:
a flat plate-shaped buffer member arranged on an upper surface side of the bottom portion, wherein

the buffer member has a side portion arranged to face the inner groove.
The sole according to claim 10, wherein a gap is formed between the side portion and the inner groove.
The sole according to claim 10, wherein the side portion projects toward the wall portion and is configured to be able to enter the inner groove.
The sole according to any one of claims 10 to 12, wherein the buffer member is provided with a plurality of through holes penetrating in a vertical direction or a plurality of non-penetrating recessed portions over an entire surface.
The sole according to any one of claims 10 to 13, wherein the buffer member is provided with a plurality of notches obtained by notching an edge portion of the buffer member.
The sole according to any one of claims 10 to 14, wherein
when width obtained as a distance from one end to another end in a width direction of the sole main body portion is W, and a range of 0.25W to 0.75W from the one end to the another end is a central region of the sole main body portion,

the buffer member is divided into right and left portions in the central region along a front-rear direction of the sole main body portion.
The sole according to any one of claims 10 to 15, wherein
when width obtained as a distance from one end to another end in a width direction of the sole main body portion is W, and a range of 0.25W to 0.75W from the one end to the another end is a central region of the sole main body portion,

at least one of an upper surface and a lower surface of the buffer member is provided with a longitudinal groove extending in the central region along a front-rear direction of the sole main body portion.
The sole according to any one of claims 10 to 16, wherein
when width obtained as a distance from one end to another end in a width direction of the sole main body portion is W, and a range of 0.25W to 0.75W from the one end to the another end is a central region of the sole main body portion,

the buffer member is provided with a plurality of through holes penetrating in a vertical direction or a plurality of non-penetrating recessed portions, and the through holes or the non-penetrating recessed portions are arranged linearly in the central region along a front-rear direction of the sole main body portion.
The sole according to any one of claims 1 to 9, further comprising:
a flat plate-shaped buffer member arranged on an upper surface side of the bottom portion, wherein

the buffer member is provided with a plurality of through holes penetrating in a vertical direction or a plurality of non-penetrating recessed portions over an entire surface.
A shoe comprising: the sole according to any one of claims 1 to 18; and an upper arranged above the sole.
The shoe according to claim 19, wherein the sole is an outsole in which a lower surface of the sole main body portion serves as a ground contact surface.