EP4778420A1

EP4778420A1 - Sole

Info

Publication number: EP4778420A1
Application number: EP24874414.6A
Authority: EP
Inventors: Hiromichi OTAKE; Takayuki KOGURE
Original assignee: Asics Corp
Current assignee: Asics Corp
Priority date: 2023-10-06
Filing date: 2024-09-04
Publication date: 2026-07-22
Also published as: CN121969272A; JP2025064437A; WO2025074802A1

Abstract

A base portion (30) of a sole body includes a high-hardness portion (33) having a predetermined hardness and a low-hardness portion (36) having a lower hardness than the high-hardness portion (33). An upper surface (31) of the base portion (30) includes a high-hardness region (33a) defined by the high-hardness portion (33) and a low-hardness region (36a) defined by the low-hardness portion (36). A plate (50) is arranged on the upper surface (31) so as to straddle a first region (51) overlapping the high-hardness region (33a) and a second region (52) overlapping the low-hardness region (36a), and includes a forefoot side plate (50a) located on the forefoot portion side and a rearfoot side plate (50b) located on the rearfoot portion side. A ratio of the second region (52) in the forefoot side plate (50a) is higher than a ratio of the second region (52) in the rearfoot side plate (50b).

Description

TECHNICAL FIELD

The present disclosure relates to a shoe sole.

BACKGROUND ART

For example, Japanese Unexamined Patent Application Publication No. 2020-54447 (Patent Literature 1) discloses a shoe sole including a midsole, a plate, a buffer, and an outsole as a shoe sole provided in a shoe used for running. In the shoe sole disclosed in Patent Literature 1, the buffer is provided for the purpose of cushioning the impact at the time of landing, and the plate is provided for the purpose of stable support of the sole of the foot and assistance of a kick-off motion.

CITATION LIST

Patent Literature

Patent Literature 1: Japanese Unexamined Patent Application Publication No. 2020-54447

DISCLOSURE OF INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

In shoes used for running, improvement of propulsive force at the time of kick-off is required to achieve efficient running.
For example, in the shoe sole disclosed in Patent Literature 1, a plate made of a material having higher hardness than the midsole is embedded inside the shoe sole, and the entire plate is bent by the movement of the center of gravity of a wearer during a period from a landing motion to a kick-off motion to generate a restoring force in the plate, thereby attempting to improve the propulsive force at the time of kick-off.
Here, from the viewpoint of improving the propulsive force at the time of kick-off, it is effective to enable smooth movement of the center of gravity from the rear to the front in a series of motions from the landing motion to the kick-off motion. In addition, if the foot wobbles in the foot width direction in the process of these motions, the propulsive force may be lost. Therefore, it is preferable to be able to suppress such wobbling of the foot.
Accordingly, the present disclosure has been made in view of the above-described problems, and an object thereof is to provide a shoe sole and a shoe provided with the same that can achieve efficient running by improving the propulsive force at the time of kick-off.

MEANS FOR SOLVING THE PROBLEMS

Provided herein is a shoe sole in which: a forefoot portion to support a toe portion and a ball portion of a wearer's foot, the forefoot portion being provided with a ground contact surface; a midfoot portion to support an arch portion of the wearer's foot; and a rearfoot portion to support a heel portion of the wearer's foot, are provided continuously along a longitudinal direction that is a direction intersecting a transverse direction matching a foot width direction of the wearer's foot and is a direction matching a foot length direction of the wearer's foot. The shoe sole based on the present disclosure includes a sole body and a plate. The sole body is continuously located from the forefoot portion to the rearfoot portion. The plate is continuously located from the forefoot portion to the rearfoot portion and is made of a material having higher hardness than a material constituting the sole body. The sole body has a base portion located closer to the ground contact surface than the plate in a direction orthogonal to the ground contact surface, the base portion including an upper surface facing the plate and a lower surface located on an opposite side to the upper surface. The base portion includes a high-hardness portion having a predetermined hardness and a low-hardness portion having a hardness lower than that of the high-hardness portion. The upper surface of the base portion includes a high-hardness region defined by the high-hardness portion and a low-hardness region defined by the low-hardness portion. The plate is disposed on the upper surface of the base portion so as to span the high-hardness region and the low-hardness region. The plate includes a first region overlapping the high-hardness region and a second region overlapping the low-hardness region when viewed along the direction orthogonal to the ground contact surface. The plate includes, in the longitudinal direction, a forefoot side plate located on the forefoot portion side and a rearfoot side plate located on the rearfoot portion side. In the shoe sole based on the present disclosure, a ratio of the second region in the forefoot side plate is higher than a ratio of the second region in the rearfoot side plate.

EFFECT OF THE INVENTION

According to the present disclosure, it is possible to provide a shoe sole and a shoe provided with the same that can achieve efficient running by improving the propulsive force at the time of kick-off.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic perspective view of a shoe according to an embodiment.
FIG. 2 is a schematic plan view of the shoe sole shown in FIG. 1.
FIG. 3 is a schematic bottom view of the shoe sole shown in FIG. 1.
FIG. 4 is a schematic side view of the shoe sole shown in FIG. 1 as viewed from a medial side.
FIG. 5 is a schematic side view of the shoe sole shown in FIG. 1 as viewed from a lateral side.
FIG. 6 is a schematic cross-sectional view taken along line VI-VI shown in FIG. 2.
FIG. 7 is a schematic cross-sectional view taken along line VII-VII shown in FIG. 2.
FIG. 8 is a schematic cross-sectional view taken along line VIII-VIII shown in FIG. 2.
FIG. 9 is a schematic cross-sectional view taken along line IX-IX shown in FIG. 2.
FIG. 10 is an exploded perspective view of the shoe sole shown in FIG. 1.
FIG. 11 is a schematic view showing an arrangement of a high-hardness portion and a low-hardness portion of a base portion of the shoe sole shown in FIG. 1.
FIG. 12 is a schematic view showing an arrangement of the base portion and a plate of the shoe sole shown in FIG. 1.
FIG. 13 is a schematic cross-sectional view for explaining a state of the shoe sole shown in FIG. 1 at the time of kick-off.
FIG. 14 is a schematic cross-sectional view for explaining a state of the shoe sole shown in FIG. 1 at the time of kick-off.
FIG. 15 is a schematic view showing an arrangement of a base portion and a plate of a shoe sole according to a first modification.
FIG. 16 is a schematic view showing an arrangement of a base portion and a plate of a shoe sole according to a second modification.
FIG. 17 is a schematic view showing an arrangement of a base portion and a plate of a shoe sole according to a third modification.
FIG. 18 is a schematic view showing an arrangement of a base portion and a plate of a shoe sole according to a fourth modification.
FIG. 19 is a schematic view showing an arrangement of a base portion and a plate of a shoe sole according to a fifth modification.
FIG. 20 is a schematic view showing an arrangement of a base portion and a plate of a shoe sole according to a sixth modification.
FIG. 21 is a schematic cross-sectional view of a shoe sole according to a seventh modification.

DESCRIPTION OF EMBODIMENTS

Embodiments of the present disclosure will be described in detail below with reference to the drawings. In the following embodiments, the same or common parts are denoted by the same reference numerals in the drawings, and the description thereof will not be repeated. In the following description, the process of the running motion of a wearer of the shoe according to an embodiment of the present disclosure and the shoe sole provided in the shoe is classified into "at the time of landing," "at the time of kick-off," and "during a period between the time of landing and the time of kick-off." "At the time of landing" means the time when the heel portion of the wearer's foot lands (the time when only the rearfoot portion of the shoe sole lands). "At the time of kick-off" means the time when the wearer is standing only on the toes of the foot (the time when the wearer is standing only on the forefoot portion of the shoe sole). "During a period between the time of landing and the time of kick-off" means the time from "at the time of landing" to "at the time of kick-off," and more specifically, means the time when the entire sole of the wearer's foot is landing (the time when all of the forefoot portion, the midfoot portion, and the rearfoot portion of the shoe sole are landing). The forefoot portion, the midfoot portion, and the rearfoot portion will be described in detail later.

FIG. 1 is a schematic perspective view of a shoe according to an embodiment. FIG. 2 is a schematic plan view of the shoe sole shown in FIG. 1. FIG. 3 is a schematic bottom view of the shoe sole shown in FIG. 1. FIG. 4 is a schematic side view of the shoe sole shown in FIG. 1 as viewed from a medial side. FIG. 5 is a schematic side view of the shoe sole shown in FIG. 1 as viewed from a lateral side. FIG. 6 is a schematic cross-sectional view taken along line VI-VI shown in FIG. 2. FIG. 7 is a schematic cross-sectional view taken along line VII-VII shown in FIG. 2. FIG. 8 is a schematic cross-sectional view taken along line VIII-VIII shown in FIG. 2. FIG. 9 is a schematic cross-sectional view taken along line IX-IX shown in FIG. 2. FIG. 10 is an exploded perspective view of the shoe sole shown in FIG. 1. A shoe 100 and a shoe sole 10 provided in the shoe according to the present embodiment will be described below with reference to FIGS. 1 to 10.
As shown in FIG. 1, the shoe 100 includes the shoe sole 10 and an upper 70. The shoe sole 10 has a substantially flat shape and includes a support surface 11 (see FIG. 2, FIG. 4, and FIG. 5, etc.) for supporting the sole of a wearer's foot, a ground contact surface 12 that lands on the ground during use such as walking and running, and a medial side surface and a lateral side surface connecting the support surface 11 and the ground contact surface 12. The upper 70 is located above the shoe sole 10 and has a shape that covers almost the entire part on the distal side of the ankle of the inserted foot of the wearer.
As shown in FIGS. 2 to 5, the shoe sole 10 is partitioned, along a longitudinal direction (vertical direction in FIGS. 2 and 3, transverse direction in FIGS. 4 and 5) that is a direction matching the foot length direction of the wearer's foot in a plan view, into a forefoot portion R1 to support a toe portion and a ball portion of the wearer's foot, a midfoot portion R2 to support an arch portion of the wearer's foot, and a rearfoot portion R3 to support a heel portion of the wearer's foot.
When a position corresponding to 40% of the dimension of the shoe sole 10 in the longitudinal direction from the front end of the shoe sole 10 is a first boundary position, and a position corresponding to 60% of the dimension of the shoe sole 10 in the longitudinal direction from the front end of the shoe sole 10 is a second boundary position, the forefoot portion R1 corresponds to a portion included between the front end and the first boundary position along the longitudinal direction, the midfoot portion R2 corresponds to a portion included between the first boundary position and the second boundary position along the longitudinal direction, and the rearfoot portion R3 corresponds to a portion included between the second boundary position and the rear end of the shoe sole along the longitudinal direction.
As shown in FIG. 2, the shoe sole 10 is partitioned, along a transverse direction (transverse direction in the figure) that is a direction matching the foot width direction of the wearer's foot in a plan view, into a medial portion (portion on the S1 side shown in the figure) that is a medial side (i.e., the side close to the midline) in the anatomical position of the foot and a lateral portion (portion on the S2 side shown in the figure) that is opposite to the medial side (i.e., the side far from the midline) in the anatomical position of the foot. The transverse direction is a direction intersecting the longitudinal direction described above.
A boundary line partitioning the shoe sole 10 into the medial portion and the lateral portion is a so-called shoe center SC. The shoe center SC is a straight line obtained by projecting, onto the shoe sole 10 along the vertical direction, a straight line connecting a portion between the first toe and the second toe and a central portion of the calcaneus (so-called heel center, which is denoted by the reference numeral HC in FIG. 2 or the like) of a standard wearer having a foot of a size suitable for the shoe 100 when the wearer wears the shoe. The front end and the rear end of the shoe sole 10 described above are ends of the shoe sole 10 located on the shoe center SC.
As shown in FIG. 1, the upper 70 includes an upper body 71, a tongue 72, and a shoelace 73. Both the tongue 72 and the shoelace 73 are fixed or attached to the upper body 71.
The upper body 71 is provided with an upper opening at its upper part to expose the upper part of the wearer's ankle and a part of the instep. The upper body 71 is provided with a lower opening at its lower part, which is covered by the shoe sole 10. A bottom part may be formed at the lower part of the upper body 71 by, for example, sewing the lower end of the upper body 71.
The tongue 72 is fixed to the upper body 71 by sewing, welding, bonding, or a combination thereof so as to cover a part of the upper opening provided in the upper body 71 that exposes a part of the instep of the wearer. As the upper body 71 and the tongue 72, for example, a woven fabric, a knitted fabric, a non-woven fabric, synthetic leather, a resin, or the like is used. Especially for shoes requiring breathability and lightweightness, a double raschel warp knitted fabric in which polyester yarns are knitted is used as the upper body 71 and the tongue 72.
The shoelace 73 is a string-like member for pulling the peripheral edges of the upper opening provided in the upper body 71, which exposes a part of the instep of the wearer, toward each other in the foot width direction of the wearer. The shoelace 73 is inserted into a plurality of holes provided at the peripheral edges of the upper opening. By tightening the shoelace 73 with the wearer's foot inserted in the upper body 71, the upper body 71 can be brought into close contact with the wearer's foot.
As shown in FIGS. 1 to 10, the shoe sole 10 includes a midsole 20 as a sole body, a plate 50, and an outsole 60.
The midsole 20 is disposed at an upper part of the shoe sole 10. The outsole 60 is disposed at a lower part of the shoe sole 10. The plate 50 is embedded inside the midsole 20.
The midsole 20 is a portion serving as a base of the shoe sole 10 and is continuously located from the forefoot portion R1 to the rearfoot portion R3 via the midfoot portion R2. The midsole 20 has a generally flat, substantially plate-like shape and is to be relatively thicker than both the outsole 60 and the plate 50.
As shown in FIGS. 6 to 10, the midsole 20 includes a base portion 30 and a cover portion 40. The base portion 30 is a part defining a lower side portion of the midsole 20. The cover portion 40 is a part defining an upper side portion of the midsole 20. In the present embodiment, the base portion 30 and the cover portion 40 are configured as separate members.
The base portion 30 is located closer to the ground contact surface 12 than the plate 50 in the vertical direction that is a direction orthogonal to the ground contact surface 12. The cover portion 40 covers the plate 50 by being located on the side opposite to the ground contact surface 12 side (i.e., the upper 70 side) of the plate in the vertical direction. Thus, the cover portion 40 having relatively low hardness is interposed between the sole of the wearer's foot and the plate 50. Therefore, compared to a case where the plate 50 is exposed toward the sole of the wearer's foot, a good wearing comfort can be provided to the wearer.
The base portion 30 includes an upper surface 31, a lower surface 32 located on the opposite side to the upper surface 31, a medial side surface, and a lateral side surface. The upper surface 31 of the base portion 30 faces the plate 50.
A missing portion 32a consisting of a through hole reaching the upper surface 31 from the lower surface 32 of the base portion 30 is provided at a central portion in the transverse direction of the lower surface 32 of the base portion 30 in a portion located at the midfoot portion R2. When viewed along the vertical direction, the missing portion 32a extends along the longitudinal direction.
Thus, in the base portion 30 in the portion located at the midfoot portion R2, the rigidity of the inner portion in the transverse direction can be made relatively lower than the rigidity of the outer portion, and in turn, the deformability of the inner portion can be made higher than the deformability of the outer portion. As a result, the shoe sole 10 can be excellent in stability, with the occurrence of excessive inward or outward rolling at the time of landing or the like suppressed. In addition, by providing the missing portion 32a as described above, the weight of the shoe sole 10 can also be reduced. Note that the missing portion 32a does not necessarily have to be configured as a hole, and may be configured as a recessed portion.
The cover portion 40 includes an upper surface 41, a lower surface 42 located on the opposite side to the upper surface 41, a medial side surface, and a lateral side surface. The upper surface 41 of the cover portion 40 defines the support surface 11 of the shoe sole 10 described above, and has a smooth curved shape so as to fit the sole of the wearer's foot. The upper surface 41 of the cover portion 40 is joined to the upper body 71 by, for example, bonding or the like. Thereby, the shoe sole 10 is fixed to the upper 70 (see FIG. 1).
The lower surface 42 of the cover portion 40 faces the plate 50. A recessed part is provided on the lower surface 42 of the cover portion 40. This recessed part is a part for receiving the plate 50. Thereby, the plate 50 and the lower surface 42 of the cover portion 40 into which the plate 50 is fitted form a smooth curved surface as a whole. The upper surface 31 of the base portion 30 has a curved shape that matches the smooth curved surface.
It is preferable that the base portion 30 and the cover portion 40 constituting the midsole 20 have appropriate strength and are excellent in cushioning property. From this viewpoint, as the base portion 30 and the cover portion 40, for example, a resin foam material containing a resin material as a main component and a foaming agent and a cross-linking agent as sub-components is used. Alternatively, a rubber foam material containing a rubber material as a main component and a plasticizer, a foaming agent, a reinforcing agent, and a cross-linking agent as sub-components may be used.
As the resin material, for example, an ethylene-vinyl acetate copolymer (EVA), a polyolefin resin, thermoplastic polyurethane, a thermoplastic polyamide elastomer (TPA, TPAE), a thermoplastic polyester elastomer, or the like can be used. As the rubber material, for example, butadiene rubber can be suitably used.
Thus, the base portion 30 and the cover portion 40 are generally composed of soft members having a small Young's modulus. Therefore, the midsole 20 composed of these members is relatively easily elastically deformed when receiving a compressive load, thereby providing excellent cushioning property.
The base portion 30 includes a high-hardness portion 33 having a predetermined hardness and a low-hardness portion 36 having a lower hardness than the high-hardness portion 33, which will be described in detail later. In addition, a method of measuring the hardness of each member constituting the shoe sole 10 and the compressive elastic modulus correlated therewith will also be described in detail later.
The plate 50 is continuously located from the forefoot portion R1 to the rearfoot portion R3 via the midfoot portion R2. The plate 50 is to be relatively thinner than the midsole 20. The plate 50 is embedded inside the midsole 20 by being sandwiched by the base portion 30 and the cover portion 40 in the vertical direction.
The plate 50 has functions such as a function of increasing the bending rigidity of the shoe sole 10, a function of causing a load to act uniformly on the base portion 30 which is a part located below the plate 50, and a function of increasing the forward propulsive force at the time of kick-off by suppressing dorsiflexion occurring in the shoe sole 10 during running.
The plate 50 is made of a material having higher hardness than the material constituting the midsole 20. As a material constituting the plate 50, for example, a fiber-reinforced resin using carbon fiber, glass fiber, aramid fiber, Dyneema fiber (registered trademark), Zylon fiber (registered trademark), boron fiber, or the like as a reinforcing fiber, or a non-foam material made of a non-fiber-reinforced resin made of a polymer resin such as a urethane thermoplastic elastomer (TPU), TPA, or EVA can be suitably used.
As shown in FIG. 10 and FIG. 12 described later, the plate 50 in a portion supporting the heel portion of the wearer's foot (i.e., a portion located at the rearfoot portion R3) has a shape branched into two toward the rear from the front. One of the parts branched into two extends along the medial peripheral edge of the shoe sole 10. The other of the parts branched into two extends along the lateral peripheral edge of the shoe sole 10. The plate 50 is not located between the parts branched into two.
Thus, in the plate 50 in the portion located at the rearfoot portion R3, the rigidity of the inner portion in the transverse direction can be made relatively lower than the rigidity of the outer portion, and in turn, the deformability of the inner portion can be made higher than that of the outer portion. As a result, the shoe sole 10 can be excellent in stability, with the occurrence of excessive inward or outward rolling at the time of landing or the like suppressed.
The outsole 60 is mainly attached to the midsole 20 and has a generally flat, substantially plate-like shape. The outsole 60 is to be relatively thinner than the midsole 20.
The outsole 60 includes an upper surface 61 and a lower surface 62. The upper surface 61 of the outsole 60 covers a large part of the lower surface 32 of the base portion 30, and is joined to the lower surface 32 of the base portion 30 by bonding or the like. The lower surface 62 of the outsole 60 defines the ground contact surface 12 of the shoe sole 10 described above.
As shown in FIG. 3, the outsole 60 is continuously located from the forefoot portion R1 to the rearfoot portion R3 via the midfoot portion R2. As described above, the missing portion 32a is provided at the central portion in the transverse direction of the lower surface 32 of the base portion 30 in the portion located at the midfoot portion R2. Therefore, the outsole 60 in the portion located from the midfoot portion R2 to the rearfoot portion R3 has a shape branched into two toward the rear from the front so as to avoid the missing portion 32a. One of the parts branched into two extends along the medial peripheral edge of the shoe sole 10. The other of the parts branched into two extends along the lateral peripheral edge of the shoe sole 10.
In other words, the outsole 60 includes a first portion 65 located at the forefoot portion R1, a second portion 66 located at the midfoot portion R2, and a third portion 67 located at the rearfoot portion R3. The first portion 65 is located throughout the forefoot portion R1. The second portion 66 is located at parts other than a part corresponding to the missing portion 32a among the medial portion, the lateral portion, and the central portion of the midfoot portion R2. The third portion 67 is located at the medial portion and the lateral portion of the rearfoot portion R3. The second portion 66 connects the first portion 65 and the third portion 67.
With this configuration, the ground contact surface 12 defined by the lower surface 62 of the outsole 60 is continuously formed from the forefoot portion R1 to the rearfoot portion R3 on the medial peripheral edge and the lateral peripheral edge of the shoe sole 10. Thereby, the rigidity of the medial peripheral edge and the lateral peripheral edge is increased correspondingly, so that excessive inward or outward rolling during running (especially at the time of landing) of the wearer can be effectively suppressed.
A plurality of through holes 62a are arranged in a staggered pattern in the outsole 60 in the portion located from the forefoot portion R1 to the midfoot portion R2. By thus imparting a tread pattern to the outsole 60, the grip property of the outsole 60 is enhanced. Furthermore, the weight of the outsole 60 is also reduced.
An opening 62b penetrating from the upper surface 61 to the lower surface 62 of the outsole 60 is provided in a portion of the outsole 60 located on the lateral side of the forefoot portion R1 and corresponding to the toe portion of the wearer's foot. The opening 62b extends along the lateral peripheral edge of the shoe sole 10. The size of the opening 62b in a plan view of the outsole 60 is to be considerably larger than the size of each of the plurality of through holes 62a.
By providing the opening 62b in the outsole 60, it is possible to effectively suppress the movement of the center of gravity of the wearer excessively toward the lateral side at the time of kick-off. As a result, smooth movement of the center of gravity from the rear to the front in a series of motions from the time of landing to the time of kick-off can be realized.
The outsole 60 is made of a material having a lower hardness than the material constituting the plate 50 and a higher hardness than the material constituting the midsole 20. Further, it is preferable that the outsole 60 is excellent in wear resistance and grip property. From these viewpoints, as a material constituting the outsole 60, for example, a member made of a material containing a rubber material as a main component and a plasticizer, a reinforcing agent, and a cross-linking agent as sub-components is used. As the rubber material, for example, butadiene rubber can be suitably used. Thereby, the outsole 60 is generally composed of a hard member having a large Young's modulus. Therefore, the outsole 60 is excellent in durability such as wear resistance.
FIG. 11 is a schematic view showing an arrangement of a high-hardness portion and a low-hardness portion of a base portion of the shoe sole shown in FIG. 1. FIG. 12 is a schematic view showing an arrangement of the base portion and a plate of the shoe sole shown in FIG. 1. FIG. 13 and FIG. 14 are both schematic cross-sectional views for explaining the state of the sole shown in FIG. 1 at the time of kick-off.
Next, with reference to FIGS. 11 to 14 and the aforementioned FIGS. 6 to 10, details of the base portion 30 of the midsole 20 included in the sole 10 according to the present embodiment, and the relationship between the base portion 30 and the plate 50 will be described. FIG. 13 is a schematic cross-sectional view for explaining a state of the shoe sole shown in FIG. 1 at the time of kick-off. FIG. 14 is a schematic cross-sectional view for explaining a state of the shoe sole shown in FIG. 1 at the time of kick-off. For easy understanding, in FIG. 11, the high-hardness portion 33 of the base portion 30 is colored dark, and the low-hardness portion of the base portion 30 is colored light. In FIG. 12, the first region 51 of the plate 50 is colored dark, and the second region 52 of the plate 50 is colored light (the same applies to FIGS. 15 to 20 described later). The first region 51 and the second region 52 will be described in detail later.
As shown in FIGS. 6 to 12, the base portion 30 includes a high-hardness portion 33 and a low-hardness portion 36. The high-hardness portion 33 is a part having a predetermined hardness. The low-hardness portion 36 is a part having a lower hardness than the high-hardness portion 33.
The high-hardness portion 33 has a generally flat, substantially plate-like shape and includes an upper surface 34 and a lower surface 35 located on the opposite side to the upper surface 34. A large part of the upper surface 34 of the high-hardness portion 33 faces the plate 50. The low-hardness portion 36 has a generally flat, substantially plate-like shape and includes an upper surface 37 and a lower surface 38 located on the opposite side to the upper surface 37. A large part of the upper surface 37 of the low-hardness portion 36 faces the plate 50.
In the present embodiment, the low-hardness portion 36 defines a part of the base portion 30 in a portion located at the forefoot portion R1. The high-hardness portion 33 defines a portion of the base portion 30 other than the portion defined by the low-hardness portion 36.
As shown in FIGS. 6, 7 and 10, a recessed part is provided in a part of the portion located at the forefoot portion R1 of the upper surface 34 of the high-hardness portion 33. In a plan view, the outer shape of this recessed part is to be substantially the same as the outer shape of the low-hardness portion 36. This recessed part is a part for receiving the low-hardness portion 36. The low-hardness portion 36 is attached to the high-hardness portion 33 by being fitted into this recessed part.
As shown in FIG. 11, the upper surface 31 of the base portion 30 includes a high-hardness region 33a defined by the upper surface 34 of the high-hardness portion 33 and a low-hardness region 36a defined by the upper surface 37 of the low-hardness portion 36. The lower surface 38 of the low-hardness portion 36 is covered with a part of the high-hardness portion 33 other than a part defining the high-hardness region 33a.
When viewed along the vertical direction (direction orthogonal to the paper surface in FIG. 11), the low-hardness region 36a is arranged at a substantially central position in both the longitudinal direction and the transverse direction of the forefoot portion R1 such that a portion supporting the sole of the foot corresponding to the MP joint of the wearer (portion denoted by reference numeral MP in the figure) traverses the low-hardness region 36a. The high-hardness region 33a is arranged at the midfoot portion R2, the rearfoot portion R3, and the forefoot portion R1 at a portion other than the portion where the low-hardness region 36a is located. Therefore, in the present embodiment, the low-hardness region 36a is surrounded by the high-hardness region 33a when viewed along the vertical direction.
By the low-hardness region 36a being located at the forefoot portion R1, smooth movement of the center of gravity from the rear to the front at the time of kick-off is realized. Thereby, a propulsive force from the rear to the front can be obtained.
As shown in FIG. 12, the plate 50 is disposed on the upper surface 31 of the base portion 30. The plate 50 is located so as to span the high-hardness region 33a and the low-hardness region 36a. Thereby, the plate 50 includes a first region 51 overlapping the high-hardness region 33a and a second region 52 overlapping the low-hardness region 36a when viewed along the vertical direction. A boundary between the first region 51 and the second region 52 extends along a direction substantially parallel to the transverse direction.
The plate 50 includes, in the longitudinal direction (vertical direction in FIG. 12), a forefoot side plate 50a located on the forefoot portion R1 side and a rearfoot side plate 50b located on the rearfoot portion R3 side. More specifically, when a position corresponding to 50% of the dimension of the plate 50 in the longitudinal direction from the front end is a longitudinal boundary position, the forefoot side plate 50a corresponds to a portion included between the front end and the longitudinal boundary position along the longitudinal direction, and the rearfoot side plate 50b corresponds to a portion included between the longitudinal boundary position and the rear end of the plate 50 along the longitudinal direction.
A ratio of the second region 52 in the forefoot side plate 50a is higher than a ratio of the second region 52 in the rearfoot side plate 50b. Note that, as in the present embodiment, when the rearfoot side plate 50b does not include the second region 52, the ratio of the second region 52 in the rearfoot side plate 50b is zero.
Further, let a virtual plane passing through a position of 20% of the total length of the shoe sole 10 from the front end of the shoe center SC and orthogonal to the shoe center SC be a first virtual plane V1, and let a virtual plane passing through a position of 60% of the total length of the shoe sole 10 from the front end of the shoe center SC and orthogonal to the shoe center SC be a second virtual plane V2. In this case, a foremost position P1 of the first region 51 in the longitudinal direction is located within a range R12 sandwiched by the first virtual plane V1 and the second virtual plane V2. Also, a portion of the plate 50 forward of the foremost position P1 of the first region 51 is constituted by the second region 52. A rearmost position P2 of the second region 52 in the longitudinal direction is located rearward of the foremost position P1 of the first region 51.
Furthermore, in a front side base portion 30a which is a portion located forward of the foremost position P1 of the first region 51 in the base portion 30, the high-hardness region 33a includes a medial portion 33a1 and a lateral portion 33a2. The medial portion 33a1 is a portion of the high-hardness region 33a arranged along the medial peripheral edge of the shoe sole 10. The lateral portion 33a2 is a portion of the high-hardness region 33a arranged along the lateral peripheral edge of the shoe sole 10.
The low-hardness region 36a is located between the medial portion 33a1 and the lateral portion 33a2. Also, in the front side base portion 30a, both end edges of the plate 50 in the transverse direction are located inward of both the medial portion 33a1 and the lateral portion 33a2. More specifically, when viewed from the vertical direction, both end edges of the plate 50 in the transverse direction are located inward of both end edges of the low-hardness region 36a in the transverse direction. Thereby, the forefoot side plate 50a can be more easily sunk downward.
With the above configuration, the shoe sole 10 can realize efficient running by improving the propulsive force at the time of kick-off. This point will be described in detail below.
As shown in FIGS. 13 and 14, at the time of kick-off, when the wearer steps in, a load is intensively applied from the sole of the foot at a part corresponding to the MP joint of the wearer's foot toward the shoe sole 10. Thereby, in the midsole 20, an especially large compressive load is applied to a portion supporting the sole of the foot corresponding to the MP joint and a portion around the portion. Further, the load accompanying the stepping in is also applied to the plate 50 embedded in the midsole 20. The forefoot side plate 50a includes a portion to which the load accompanying the stepping in is applied.
In the present embodiment, as described above, the shoe sole 10 is configured such that the ratio of the second region 52 in the forefoot side plate 50a is higher than the ratio of the second region 52 in the rearfoot side plate 50b.
With this configuration, the forefoot side plate 50a can be more easily sunk downward than the rearfoot side plate 50b. Therefore, when the load is applied to the plate 50, the forefoot side plate 50a can be elastically deformed so as to be greatly bent downward.
When the forefoot side plate 50a is elastically deformed so as to be bent downward in this way, a propulsive force from the rear toward the front can be obtained by a repulsive force generated by the elastically deformed forefoot side plate 50a. Further, smooth movement of the center of gravity from the rear toward the front can also be realized, which also makes it possible to obtain a propulsive force. As a result, the propulsive force at the time of kick-off is improved, and the shoe sole 10 can realize efficient running.
Therefore, by using the shoe sole 10 according to the present embodiment described above and the shoe 100 provided with the same, efficient running can be realized by improving the propulsive force at the time of kick-off.
In the present embodiment, as described above, a portion of the plate 50 forward of the foremost position P1 of the first region 51, which is located so as to span the high-hardness region 33a and the low-hardness region 36a, is constituted by the second region 52. That is, when focusing on the foremost position P1 and the vicinity thereof, a portion of the plate 50 rearward of the foremost position P1 is supported by the high-hardness region 33a having a relatively high hardness, and a portion of the plate 50 forward of the foremost position P1 is supported by the low-hardness region 36a having a relatively low hardness.
With this configuration, when the load is applied to the plate 50, the portion forward of the foremost position P1 of the first region 51 can be elastically deformed so as to be greatly bent downward.
Even when the forward portion of the plate 50 is elastically deformed so as to be bent downward in this way, a propulsive force from the rear toward the front can be obtained by a repulsive force generated by the elastically deformed plate 50. Further, smooth movement of the center of gravity from the rear toward the front can also be realized, which also makes it possible to obtain a propulsive force.
From the viewpoint of ensuring the maximum repulsive force of the plate 50, it is preferable that a portion of the plate 50 located below at least a portion of the sole of the wearer's foot corresponding to the MP joint and the periphery thereof is constituted by the second region 52. In other words, the foremost position P1 of the first region 51 is preferably located rearward of a predetermined position in the longitudinal direction.
In addition, from the viewpoint of realizing smoother movement of the center of gravity from the rear to the front, it is preferable that the portion of the plate 50 that is elastically deformed as described above is unevenly distributed forward accordingly. In other words, the foremost position P1 of the first region 51 is preferably located forward of a predetermined position in the longitudinal direction.
In this regard, in the present embodiment, as described above, the foremost position P1 of the first region 51 is located within the range R12 sandwiched by the first virtual plane V1 and the second virtual plane V2. With this configuration, both the propulsive force derived from the repulsive force of the plate 50 described above and the propulsive force derived from the smooth movement of the center of gravity from the rear toward the front can be obtained.
Further, in the present embodiment, as described above, in the front side base portion 30a, the low-hardness region 36a is located between the medial portion 33a1 and the lateral portion 33a2 of the high-hardness region 33a. By thus making the inner portion in the transverse direction of the upper surface 31 of the front side base portion 30a have lower hardness than the outer portion, the rigidity of the inner portion can be made relatively lower than the rigidity of the outer portion. As a result, since occurrence of excessive inward or outward rolling in a series of motions from the time of landing to the time of kick-off is suppressed, the shoe sole 10 can realize smooth movement of the center of gravity from the rear toward the front.
Further, as described above, in the front side base portion 30a, both end edges of the plate 50 in the transverse direction are located inward of both the medial portion 33a1 and the lateral portion 33a2. This can prevent the above-mentioned bending deformation of the forward portion of the plate 50 from being hindered by the plate 50 being located so as to bridge the medial portion 33a1 and the lateral portion 33a2. Therefore, the shoe sole 10 can have an improved propulsive force at the time of kick-off.
Furthermore, in the present embodiment, as described above, the boundary between the first region 51 and the second region 52 of the plate 50 extends along a direction substantially parallel to the transverse direction. With this configuration, the above-mentioned bending deformation of the forward portion of the plate 50 can be caused more uniformly along the transverse direction. Therefore, the shoe sole 10 can have an improved stability at the time of kick-off.
In the present embodiment, as described above, the rearmost position P2 of the second region 52 is located rearward of the foremost position P1 of the first region 51. With this configuration, smoother movement of the center of gravity from the rear to the front can be realized at the time of kick-off.
In the present embodiment described above, a case where the midsole 20 is composed of the base portion 30 and the cover portion 40 formed separately from each other has been described as an example, but the midsole 20 may be composed of a base portion 30 and a cover portion 40 formed integrally. In this case, for example, the midsole 20 in which the plate 50 is embedded can be obtained by inserting the plate 50 during casting or injection molding of the midsole 20.
In the present embodiment described above, a case where the base portion 30 and the cover portion 40 constituting the midsole 20 are composed of a resin foam material has been described as an example, but the base portion 30 and the cover portion 40 may be composed of, for example, a modeled object manufactured by a stereolithography-type three-dimensional additive manufacturing method.
Further, in the present embodiment described above, a case where the rearmost position P2 of the second region 52 in the longitudinal direction is located rearward of the foremost position P1 of the first region 51 has been described as an example, but the rearmost position P2 may be arranged at a position corresponding to the foremost position P1 of the first region 51 in the longitudinal direction.

The hardness of each member constituting the shoe sole 10 is measured by a measurement method in accordance with the hardness test of JIS K7312, which will be described below. More specifically, first, a test piece having a predetermined thickness or more is prepared. Next, the test piece is placed on a flat surface. Next, the pressure surface of a durometer is pressed against the test piece so that the indenter is perpendicular to the measurement surface of the test piece. An instantaneous value obtained when the pressure surface is pressed against the test piece is taken as a measured value of the hardness of the test piece. The above measurement is performed five times so that the contact points of the indenter are at positions at least 6 mm apart from each other, and a median value of the five measured values thus obtained is taken as the hardness of the test piece. When the thickness of the test piece is less than a prescribed value, test pieces of the same type may be laminated.
As the base portion 30 of the midsole 20, it is preferable to use one in which the hardness of the low-hardness portion 36 is lower than the hardness of the high-hardness portion 33 by 8 or more, but it is not particularly limited thereto. The hardness of the base portion 30 of the midsole 20 is measured by a Type C durometer (Asker C type) in accordance with JIS K6253.
As an example, the outsole 60 has a hardness of 50 or more and 80 or less, and the plate 50 has a hardness of 60 or more. The hardness of the outsole 60 is measured by a Type A durometer (Asker A type) in accordance with JIS K6253. The hardness of the plate 50 is measured by a Type D durometer (Asker D type) in accordance with JIS K6253.

Generally, there is a correlation between the hardness of a member and the compressive elastic modulus such that the compressive elastic modulus is high when the hardness is high, and the compressive elastic modulus is low when the hardness is low.
The compressive elastic modulus of each member constituting the shoe sole 10 is measured by a measurement method in accordance with the compression test (method A) of JIS K6254: 2016 described below. More specifically, first, a cylindrical test piece having a thickness of 12 mm or more and 13 mm or less and a diameter of 28.5 mm or more and 29.5 mm or less is prepared. Next, lubricating oil is applied to a pair of metal plates of a compression tester. Next, the test piece is compressed by being sandwiched between the pair of metal plates from both sides in a direction corresponding to the vertical direction which is the direction orthogonal to the ground contact surface 12. The compressive force is unloaded when the strain of the test piece reaches 25% by this compression. In the stress-strain curve of the test piece obtained by this compression, an initial gradient until the strain of the test piece reaches 5% is calculated as the compressive elastic modulus of the test piece.
As the base portion 30 of the midsole 20, one in which the compressive elastic modulus of the low-hardness portion 36 is lower than the compressive elastic modulus of the high-hardness portion 33 is used. The compressive elastic modulus of the low-hardness portion 36 is preferably 0.25 times or more and less than 1.0 times the compressive elastic modulus of the high-hardness portion 33. More preferably, the compressive elastic modulus of the low-hardness portion 36 is 0.3 times or more and less than 0.75 times the compressive elastic modulus of the high-hardness portion 33.

FIG. 15 is a schematic view showing an arrangement of a base portion and a plate of a shoe sole according to a first modification. A shoe sole 10A according to a first modification based on the above embodiment will be described below with reference to FIG. 15.
As shown in FIG. 15, the shoe sole 10A according to the first modification differs only in the shape of the plate 50 from the shoe sole 10 according to the above embodiment.
More specifically, in the present modification, one of both end edges of the plate 50 in the transverse direction is located so as to overlap a boundary between the low-hardness region 36a and the medial portion 33a1 of the high-hardness region 33a. Also, the other of both end edges of the plate 50 in the transverse direction is located so as to overlap a boundary between the low-hardness region 36a and the lateral portion 33a2 of the high-hardness region 33a.
Even in the case of this configuration, effects similar to the effects described in the above embodiment can be obtained, and a shoe sole and a shoe provided with the same can realize efficient running by improving the propulsive force at the time of kick-off.

FIG. 16 is a schematic view showing an arrangement of a base portion and a plate of a shoe sole according to a second modification. A shoe sole 10B according to a second modification based on the above embodiment will be described below with reference to FIG. 16.
As shown in FIG. 16, the shoe sole 10B according to the second modification differs only in the configuration of the base portion 30 from the shoe sole 10 according to the above embodiment.
More specifically, in the present modification, the position of the front end of the low-hardness portion 36 of the base portion 30 coincides with the position of the front end of the base portion 30.
Even in the case of this configuration, effects similar to the effects described in the above embodiment can be obtained, and a shoe sole and a shoe provided with the same can realize efficient running by improving the propulsive force at the time of kick-off.

FIG. 17 is a schematic view showing an arrangement of a base portion and a plate of a shoe sole according to a third modification. A shoe sole 10C according to a third modification based on the above embodiment will be described below with reference to FIG. 17.
As shown in FIG. 17, the shoe sole 10C according to the third modification differs only in the configuration of the base portion 30 from the shoe sole 10 according to the above embodiment.
More specifically, in the present modification, the base portion 30 is configured such that the rear end of the low-hardness portion 36 of the base portion 30 is located at the midfoot portion R2.
Even in the case of this configuration, effects similar to the effects described in the above embodiment can be obtained, and a shoe sole and a shoe provided with the same can realize efficient running by improving the propulsive force at the time of kick-off.

FIG. 18 is a schematic view showing an arrangement of a base portion and a plate of a shoe sole according to a fourth modification. A shoe sole 10D according to a fourth modification based on the above embodiment will be described below with reference to FIG. 18.
As shown in FIG. 18, the shoe sole 10D according to the fourth modification differs only in the configuration of the base portion 30 from the shoe sole 10 according to the above embodiment.
More specifically, in the present modification, the base portion 30 is configured such that the rear end of the low-hardness portion 36 of the base portion 30 is located at the rearfoot portion R3.
Even in the case of this configuration, effects similar to the effects described in the above embodiment can be obtained, and a shoe sole and a shoe provided with the same can realize efficient running by improving the propulsive force at the time of kick-off.

FIG. 19 is a schematic view showing an arrangement of a base portion and a plate of a shoe sole according to a fifth modification. A shoe sole 10E according to a fifth modification based on the above embodiment will be described below with reference to FIG. 19.
As shown in FIG. 19, the shoe sole 10E according to the fifth modification differs only in the configuration of the base portion 30 from the shoe sole 10 according to the above embodiment.
More specifically, in the present modification, the base portion 30 is configured such that the low-hardness portion 36 defines almost the entire part of the base portion 30 in the portion located at the forefoot portion R1.
Even in the case of this configuration, effects similar to the effects described in the above embodiment can be obtained, and a shoe sole and a shoe provided with the same can realize efficient running by improving the propulsive force at the time of kick-off.

FIG. 20 is a schematic view showing an arrangement of a base portion and a plate of a shoe sole according to a sixth modification. A shoe sole 10F according to a sixth modification based on the above embodiment will be described below with reference to FIG. 20.
As shown in FIG. 20, the shoe sole 10F according to the sixth modification differs only in the shape of the plate 50 from the shoe sole 10 according to the above embodiment.
More specifically, in the present modification, the plate 50 is configured such that the front end of the plate 50 is located forward of the front end of the low-hardness portion 36 of the base portion 30. Therefore, the plate 50 is located so as to bridge the front end and the rear end of the low-hardness portion 36.
Even in the case of this configuration, effects similar to the effects described in the above embodiment can be obtained, and a shoe sole and a shoe provided with the same can realize efficient running by improving the propulsive force at the time of kick-off.

FIG. 21 is a schematic cross-sectional view of a shoe sole according to a seventh modification. A shoe sole 10G according to a seventh modification based on the above embodiment will be described below with reference to FIG. 21.
As shown in FIG. 21, the shoe sole 10G according to the seventh modification differs only in the configuration of the base portion 30 from the shoe sole 10 according to the above embodiment.
More specifically, in the present modification, the low-hardness portion 36 reaches from the upper surface 31 to the lower surface 32 of the base portion 30. Therefore, in the present modification, the above-mentioned recessed part for receiving the low-hardness portion 36 is not provided in the upper surface 34 of the high-hardness portion 33.
Even in the case of this configuration, effects similar to the effects described in the above embodiment can be obtained, and a shoe sole and a shoe provided with the same can realize efficient running by improving the propulsive force at the time of kick-off.

The characteristic points disclosed in the above-described embodiment and modifications thereof are summarized as follows.

[Aspect 1]

A shoe sole according to an aspect of the present disclosure is a shoe sole in which: a forefoot portion to support a toe portion and a ball portion of a wearer's foot, the forefoot portion being provided with a ground contact surface; a midfoot portion to support an arch portion of the wearer's foot; and a rearfoot portion to support a heel portion of the wearer's foot, are provided continuously along a longitudinal direction that is a direction intersecting a transverse direction matching a foot width direction of the wearer's foot and is a direction matching a foot length direction of the wearer's foot, the shoe sole including: a sole body continuously located from the forefoot portion to the rearfoot portion; and a plate continuously located from the forefoot portion to the rearfoot portion and made of a material having higher hardness than a material constituting the sole body, the sole body has a base portion located closer to the ground contact surface than the plate in a direction orthogonal to the ground contact surface, the base portion including an upper surface facing the plate and a lower surface located on an opposite side to the upper surface, the base portion includes a high-hardness portion having a predetermined hardness and a low-hardness portion having a hardness lower than that of the high-hardness portion, the upper surface of the base portion includes a high-hardness region defined by the high-hardness portion and a low-hardness region defined by the low-hardness portion, the plate is disposed on the upper surface of the base portion so as to span the high-hardness region and the low-hardness region, the plate includes a first region overlapping the high-hardness region and a second region overlapping the low-hardness region when viewed along the direction orthogonal to the ground contact surface, the plate includes, in the longitudinal direction, a forefoot side plate located on the forefoot portion side and a rearfoot side plate located on the rearfoot portion side, and a ratio of the second region in the forefoot side plate is higher than a ratio of the second region in the rearfoot side plate.
With this configuration, it is possible to realize efficient running by improving the propulsive force at the time of kick-off.

[Aspect 2]

In the shoe sole according to aspect 1, when a virtual plane passing through a position of 20% of the total length of the shoe sole from a front end of a shoe center of the shoe sole and orthogonal to the shoe center is defined as a first virtual plane, and a virtual plane passing through a position of 60% of the total length of the shoe sole from the front end of the shoe center and orthogonal to the shoe center is defined as a second virtual plane, a foremost position of the first region in the longitudinal direction is located within a range sandwiched by the first virtual plane and the second virtual plane, and a portion of the plate forward of the foremost position of the first region is constituted by the second region.
With this configuration, both the propulsive force derived from the repulsive force of the plate and the propulsive force derived from the smooth movement of the center of gravity from the rear toward the front can be maximally obtained.

[Aspect 3]

In the shoe sole according to aspect 2, a rearmost position of the second region in the longitudinal direction may be located at a position corresponding to the foremost position of the first region in the longitudinal direction, or may be located rearward of the foremost position of the first region.
With this configuration, smoother movement of the center of gravity from the rear to the front can be realized at the time of kick-off.

[Aspect 4]

In the shoe sole according to aspect 2 or 3, in a front side base portion which is a portion located forward of the foremost position of the first region in the base portion, the high-hardness region includes a medial portion arranged along the medial peripheral edge of the shoe sole and a lateral portion arranged along the lateral peripheral edge of the shoe sole, and the low-hardness region may be located between the medial portion and the lateral portion. In this case, both end edges of the plate in the transverse direction may be located inward of both the medial portion and the lateral portion in the front side base portion, or one of the both end edges of the plate in the transverse direction may be located so as to overlap a boundary between the medial portion and the low-hardness region and the other may be located so as to overlap a boundary between the lateral portion and the low-hardness region.
With this configuration, it is possible to prevent the above-mentioned bending deformation of the forward portion of the plate from being hindered by the plate being located so as to bridge the medial portion and the lateral portion.

[Aspect 5]

In the shoe sole according to any one of aspects 1 to 4, the low-hardness region may be surrounded by the high-hardness region when viewed along the direction orthogonal to the ground contact surface.
With this configuration, the low-hardness region can be formed in a spot shape on the upper surface of the base portion.

[Aspect 6]

In the shoe sole according to any one of aspects 1 to 5, the boundary between the first region and the second region may extend along a direction substantially parallel to the transverse direction.
With this configuration, the above-mentioned bending deformation of the forward portion of the plate can be caused more uniformly along the transverse direction. Therefore, a shoe sole having improved stability at the time of kick-off can be obtained.

[Aspect 7]

In the shoe sole according to any one of aspects 1 to 6, the lower surface of the low-hardness portion may be covered with a part of the high-hardness portion other than the part defining the high-hardness region. With this configuration, appropriate rigidity can be imparted to the base portion.

[Aspect 8]

In the shoe sole according to any one of aspects 1 to 6, the low-hardness portion may reach from the upper surface of the base portion to the lower surface of the base portion.
With this configuration, the plate can be more easily sunk downward in the second region.

[Aspect 9]

In the shoe sole according to any one of aspects 1 to 8, a missing portion consisting of either a recessed portion or a hole may be provided at a central portion in the transverse direction of the lower surface of the base portion in a portion located at the midfoot portion.
With this configuration, in the base portion in the portion located at the midfoot portion, the rigidity of the inner portion in the transverse direction can be made relatively lower than the rigidity of the outer portion, and in turn, the deformability of the inner portion can be made higher than the deformability of the outer portion. As a result, the shoe sole can be excellent in stability, with the occurrence of excessive inward or outward rolling at the time of landing or the like suppressed. In addition, with this configuration, the weight of the shoe sole can also be reduced.

[Aspect 10]

In the shoe sole according to any one of aspects 1 to 9, the sole body may further have a cover portion covering the plate by being located on the side opposite to the ground contact surface side of the plate in the direction orthogonal to the ground contact surface.
With this configuration, compared to a case where the plate is exposed toward the sole of the wearer's foot, a good wearing comfort can be provided to the wearer.

[Aspect 11]

In the shoe sole according to aspect 10, the cover portion may be configured as a separate body from the base portion. In this case, the plate may be embedded by being sandwiched by the base portion and the cover portion in the direction orthogonal to the ground contact surface.
With this configuration, the sole body in which the plate is embedded can be formed relatively easily.

[Aspect 12]

In the shoe sole according to any one of aspects 1 to 11, the plate in a portion supporting the heel portion of the wearer's foot may have a shape branched into two toward the rear from the front.
With this configuration, in the plate in the portion supporting the heel portion of the wearer's foot, the rigidity of the inner portion in the transverse direction can be made relatively lower than the rigidity of the outer portion, and in turn, the deformability of the inner portion can be made higher than that of the outer portion. As a result, the shoe sole can be excellent in stability, with the occurrence of excessive inward or outward rolling at the time of landing or the like suppressed.

[Aspect 13]

The shoe sole according to any one of aspects 1 to 12 may further include an outsole covering the lower surface of the base portion and defining the ground contact surface. In this case, it is preferable that the outsole is made of a material having a lower hardness than the material constituting the plate and a higher hardness than the material constituting the sole body. Also, in this case, the outsole may include a first portion located at the forefoot portion, a second portion located at the midfoot portion, and a third portion located at the rearfoot portion, and the second portion may be located at least at the medial portion and the lateral portion of the midfoot portion so as to connect the first portion and the third portion.
With this configuration, the ground contact surface defined by the lower surface of the outsole is continuously formed from the forefoot portion to the rearfoot portion R on the medial peripheral edge and the lateral peripheral edge of the shoe sole. Thereby, the rigidity of the medial peripheral edge and the lateral peripheral edge is increased correspondingly, so that excessive inward or outward rolling during running (especially at the time of landing) of the wearer can be effectively suppressed.

[Aspect 14]

In the shoe sole according to aspect 13, an opening may be provided in a portion of the outsole located on the lateral side of the forefoot portion and corresponding to the toe portion of the wearer's foot.
With this configuration, it is possible to effectively suppress the movement of the center of gravity of the wearer excessively toward the lateral side at the time of kick-off. As a result, smooth movement of the center of gravity from the rear to the front in a series of motions from the time of landing to the time of kick-off can be realized.

[Aspect 15]

In the shoe sole according to any one of aspects 1 to 14, the sole body may be composed of a foam material made of resin or rubber.
With this configuration, the sole body can have appropriate strength and excellent cushioning property.

[Aspect 16]

In the shoe sole according to any one of aspects 1 to 15, the plate may be composed of a non-foam material made of resin.
With this configuration, it is possible to increase the bending rigidity of the shoe sole and to increase the forward propulsive force at the time of kick-off by suppressing dorsiflexion occurring in the shoe sole during running.

[Aspect 17]

A shoe according to an aspect of the present disclosure includes: the shoe sole according to any one of aspects 1 to 16; and an upper provided above the shoe sole.
With this configuration, it is possible to realize efficient running by improving the propulsive force at the time of kick-off.

The shapes, sizes, and the like of the midsole, the outsole, and the plate constituting the shoe sole can be variously changed without departing from the spirit of the present invention. In addition, the configuration, shape, and the like of the upper can also be variously changed.
Furthermore, the characteristic configurations shown in the above-described embodiment and modifications thereof can be combined with each other without departing from the spirit of the present invention.
As described above, the embodiment and its modifications disclosed herein are illustrative in all respects and are not restrictive. The technical scope of the present invention is defined by the claims, and includes all changes within the meaning and scope equivalent to those of the claims.

DESCRIPTION OF REFERENCE NUMERALS

10, 10A-10G shoe sole
11 support surface
12 ground contact surface
20 midsole
30 base portion
30a front side base portion
31 upper surface
32 lower surface
32a missing portion
33 high-hardness portion
33a high-hardness region
33a1 medial portion
33a2 lateral portion
34 upper surface
35 lower surface
36 low-hardness portion
36a low-hardness region
37 upper surface
38 lower surface
40 cover portion
41 upper surface
42 lower surface
50 plate
50a forefoot side plate
50b rearfoot side plate
51 first region
52 second region
60 outsole
61 upper surface
62 lower surface
62a through hole
62b opening
65 first portion
66 second portion
67 third portion
70 upper
71 upper body
72 tongue
73 shoelace
100 shoe
R1 forefoot portion
R2 midfoot portion
R3 rearfoot portion
SC shoe center
V1 first virtual plane
V2 second virtual plane

Claims

A shoe sole in which: a forefoot portion to support a toe portion and a ball portion of a wearer's foot, the forefoot portion being provided with a ground contact surface; a midfoot portion to support an arch portion of the wearer's foot; and a rearfoot portion to support a heel portion of the wearer's foot, are provided continuously along a longitudinal direction that is a direction intersecting a transverse direction matching a foot width direction of the wearer's foot and is a direction matching a foot length direction of the wearer's foot, the shoe sole comprising:
a sole body continuously located from the forefoot portion to the rearfoot portion; and

a plate continuously located from the forefoot portion to the rearfoot portion and made of a material having higher hardness than a material constituting the sole body,

wherein the sole body has a base portion located closer to the ground contact surface than the plate in a direction orthogonal to the ground contact surface, the base portion including an upper surface facing the plate and a lower surface located on an opposite side to the upper surface,

the base portion includes a high-hardness portion having a predetermined hardness and a low-hardness portion having a hardness lower than that of the high-hardness portion,

the upper surface of the base portion includes a high-hardness region defined by the high-hardness portion and a low-hardness region defined by the low-hardness portion,

the plate is disposed on the upper surface of the base portion so as to span the high-hardness region and the low-hardness region,

the plate includes a first region overlapping the high-hardness region and a second region overlapping the low-hardness region when viewed along the direction orthogonal to the ground contact surface,

the plate includes, in the longitudinal direction, a forefoot side plate located on the forefoot portion side and a rearfoot side plate located on the rearfoot portion side, and

a ratio of the second region in the forefoot side plate is higher than a ratio of the second region in the rearfoot side plate.
The shoe sole according to claim 1, wherein when a virtual plane passing through a position of 20% of a total length of the shoe sole from a front end of a shoe center of the shoe sole and orthogonal to the shoe center of the shoe sole is defined as a first virtual plane, and a virtual plane passing through a position of 60% of the total length of the shoe sole from the front end of the shoe center of the shoe sole and orthogonal to the shoe center of the shoe sole is defined as a second virtual plane, a foremost position of the first region in the longitudinal direction is located within a range sandwiched by the first virtual plane and the second virtual plane, and a portion of the plate forward of the foremost position of the first region is constituted by the second region.
The shoe sole according to claim 2, wherein a rearmost position of the second region in the longitudinal direction is located at a position corresponding to the foremost position of the first region in the longitudinal direction, or is located rearward of the foremost position of the first region.
The shoe sole according to claim 2, wherein in a front side base portion which is a portion located forward of the foremost position of the first region in the base portion, the high-hardness region includes a medial portion arranged along a medial peripheral edge of the shoe sole and a lateral portion arranged along a lateral peripheral edge of the shoe sole, and the low-hardness region is located between the medial portion and the lateral portion, and
both end edges of the plate in the transverse direction are located inward of both the medial portion and the lateral portion in the front side base portion, or one of the both end edges of the plate in the transverse direction is located so as to overlap a boundary between the medial portion and the low-hardness region and the other is located so as to overlap a boundary between the lateral portion and the low-hardness region.
The shoe sole according to claim 1, wherein when viewed along the direction orthogonal to the ground contact surface, the low-hardness region is surrounded by the high-hardness region.
The shoe sole according to claim 1, wherein a boundary between the first region and the second region extends along a direction substantially parallel to the transverse direction.
The shoe sole according to claim 1, wherein a lower surface of the low-hardness portion is covered with a part of the high-hardness portion other than the part defining the high-hardness region.
The shoe sole according to claim 1, wherein the low-hardness portion reaches from the upper surface of the base portion to the lower surface of the base portion.
The shoe sole according to claim 1, wherein a missing portion consisting of either a recessed portion or a hole is provided at a central portion in the transverse direction of the lower surface of the base portion in a portion located at the midfoot portion.
The shoe sole according to claim 1, the sole body further having a cover portion that covers the plate by being located on a side opposite to the ground contact surface side with respect to the plate in the direction orthogonal to the ground contact surface.
The shoe sole according to claim 10, wherein
the cover portion is configured as a separate body from the base portion, and

the plate is embedded by being sandwiched between the base portion and the cover portion in the direction orthogonal to the ground contact surface.
The shoe sole according to claim 1, wherein a portion of the plate that supports a heel portion of a wearer's foot has a shape that branches into two from front toward rear.
The shoe sole according to claim 1, further comprising an outsole that covers the lower surface of the base portion and defines the ground contact surface,
wherein the outsole is made of a material having a lower hardness than a material constituting the plate and a higher hardness than a material constituting the sole body,

the outsole includes a first portion located in the forefoot portion, a second portion located in the midfoot portion, and a third portion located in the rearfoot portion, and

the second portion is located at least in a medial portion and a lateral portion of the midfoot portion so as to connect the first portion and the third portion.
The shoe sole according to claim 13, wherein an opening is provided in a portion of the outsole that is located on a lateral side of the forefoot portion and corresponds to a toe portion of a wearer's foot.
The shoe sole according to claim 1, wherein the sole body is made of a foam material made of resin or rubber.
The shoe sole according to claim 1, wherein the plate is made of a non-foam material made of resin.
A shoe comprising:
the shoe sole according to any one of claims 1 to 16; and

an upper provided above the sole.