Sole

Abstract

A sole (10) includes a sole body and a plate (50) which are each located continuously from a forefoot portion to a hindfoot portion. The sole body includes a base portion (30), and the base portion (30) includes a high hardness portion (33) which has a prescribed hardness and a low hardness portion (36) which has a hardness lower than the hardness of the high hardness portion (33). An upper surface (31) of the base portion (30) includes a high hardness region (33a) which is defined by the high hardness portion (33) and a low hardness region (36a) which is defined by the low hardness portion (36). The plate (50) includes a first region (51) and a second region (52) which overlap the high hardness region (33a) and the low hardness region (36a), respectively, by the plate (50) being disposed on the upper surface (31) so as to extend over the high hardness region (33a) and the low hardness region (36a). The plate (50) includes a forefoot portion side plate (50a) which is located on the forefoot portion side and a hindfoot portion side plate (50b) which is located on the hindfoot portion side. The proportion of the second region (52) in the forefoot portion side plate (50a) is higher than the proportion of the second region (52) in the hindfoot portion side plate (50b).

Description

shoe sole

[0001] The present disclosure relates to shoe soles.

[0002] For example, Japanese Patent Laid-Open Publication No. 2020-54447 (Patent Document 1) discloses a sole for a running shoe, which includes a midsole, a plate, a shock absorber, and an outsole. The sole disclosed in Patent Document 1 is provided with a shock absorber for the purpose of absorbing shock when the foot touches the ground, and a plate for the purpose of providing stable support for the sole of the foot and assisting in the kicking motion.

[0003] Japanese Patent Application Laid-Open No. 2020-54447

[0004] Shoes used for running are required to have improved propulsive force when taking off in order to enable efficient running.

[0005] For example, in the sole disclosed in Patent Document 1, a plate made of a material harder than the midsole is embedded inside the sole, and the entire plate is deflected by the wearer's shift in center of gravity between landing and pushing off, generating a restoring force in the plate, thereby improving propulsion force when pushing off.

[0006] From the perspective of improving propulsion when pushing off, it is effective to enable a smooth movement of the center of gravity from rear to front in the series of movements from landing to pushing off. Furthermore, if the foot wobbles in the width direction during these movements, propulsion may be lost, so it is preferable to be able to suppress such foot wobbling.

[0007] Therefore, the present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a sole and a shoe equipped with the sole that can achieve efficient running by improving propulsion force when kicking off.

[0008] A shoe sole according to the present disclosure has a ground contact surface and includes a forefoot portion configured to support the toes and forefoot of a wearer's foot, a midfoot portion configured to support the arch of the wearer's foot, and a rearfoot portion configured to support the heel of the wearer's foot, which are arranged in a longitudinal direction that intersects with the left-right direction, which corresponds to the width direction of the wearer's foot, and corresponds to the length direction of the wearer's foot. The shoe sole according to the present disclosure includes a sole body and a plate. The sole body is located continuously from the forefoot portion to the rearfoot portion. The plate is located continuously from the forefoot portion to the rearfoot portion and is made of a material harder than the 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 perpendicular to the ground contact surface, and includes an upper surface facing the plate and a lower surface located opposite the upper surface. The base portion includes a high hardness portion having a predetermined hardness and a low hardness portion having a lower hardness than 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. When viewed in a direction perpendicular to the ground surface, the plate includes a first region overlapping the high hardness region and a second region overlapping the low hardness region. The plate includes a forefoot-side plate located closer to the forefoot than to the rearfoot in the longitudinal direction. In the sole according to the present disclosure, the proportion of the second region in the forefoot-side plate is higher than the proportion of the second region in the rearfoot-side plate.

[0009] According to the present disclosure, it is possible to provide a shoe sole and a shoe equipped with the same that can achieve efficient running by improving propulsion force when pushing off.

[0010] 1 is a schematic perspective view of a shoe according to an embodiment. FIG. 1 is a schematic plan view of the shoe sole shown in FIG. 1. FIG. 2 is a schematic bottom view of the shoe sole shown in FIG. 1. FIG. 3 is a schematic side view of the shoe sole shown in FIG. 1, viewed from the medial side of the foot. FIG. 4 is a schematic side view of the shoe sole shown in FIG. 1, viewed from the lateral side of the foot. FIG. 5 is a schematic cross-sectional view taken along line VI-VI in FIG. 2. FIG. 6 is a schematic cross-sectional view taken along line VII-VII in FIG. 2. FIG. 7 is a schematic cross-sectional view taken along line VIII-VIII in FIG. 2. FIG. 8 is a schematic cross-sectional view taken along line IX-IX in FIG. 2. FIG. 9 is an exploded perspective view of the shoe sole shown in FIG. 1. FIG. 10 is a schematic view showing the arrangement of high hardness portions and low hardness portions of the base portion of the sole shown in FIG. 1. FIG. 11 is a schematic view showing the arrangement of the base portion and plate of the sole shown in FIG. 1. FIG. 12 is a schematic cross-sectional view for explaining the state of the sole shown in FIG. 1 at the time of kicking off. FIG. 13 is a schematic cross-sectional view for explaining the state of the sole shown in FIG. 1 at the time of kicking off. FIG. 14 is a schematic view showing the arrangement of the base portion and plate of the sole according to a first modified example. FIG. 15 is a schematic view showing the arrangement of the base portion and plate of the sole according to a second modified example. Fig. 10 is a schematic diagram showing the arrangement of the base portion and plate of the sole according to a third modified example. Fig. 11 is a schematic diagram showing the arrangement of the base portion and plate of the sole according to a fourth modified example. Fig. 12 is a schematic diagram showing the arrangement of the base portion and plate of the sole according to a fifth modified example. Fig. 13 is a schematic diagram showing the arrangement of the base portion and plate of the sole according to a sixth modified example. Fig. 14 is a schematic cross-sectional view of a sole according to a seventh modified example.

[0011] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the embodiments described below, identical or common parts are designated by the same reference numerals in the drawings, and their description will not be repeated. In the following description, the running motion process of a wearer of a shoe according to an embodiment of the present disclosure and a sole provided therewith is divided into "foot contact," "kicking off," and "a time between foot contact and kicking off." "Foot contact" refers to the time when the heel of the wearer's foot lands on the ground (the time when only the rear part of the sole lands on the ground). "Kicking off" refers to the time when the wearer is standing on only the toes of the foot (the time when only the forefoot part of the sole lands on the ground). "A time between foot contact and kicking off" refers to the time from "foot contact" to "kicking off," and more specifically, refers to the time when the entire sole of the wearer's foot lands on the ground (the time when the forefoot part, midfoot part, and rearfoot part of the sole all land on the ground). The forefoot, midfoot and rearfoot will be described in more detail below.

[0012] <Embodiment> 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. Figs. 4 and 5 are schematic side views of the shoe sole shown in Fig. 1 as seen from the medial side and the lateral side, respectively. 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 according to this embodiment and a sole 10 provided therewith will now be described with reference to Figs. 1 to 10.

[0013] As shown in Figure 1, shoe 100 comprises a sole 10 and an upper 70. Sole 10 has a generally flat shape and comprises a support surface 11 (see Figures 2, 4, 5, etc.) that supports the sole of the wearer's foot, a ground contact surface 12 that comes into contact with the ground when walking, running, or otherwise using the shoe, and medial and lateral side surfaces that connect support surface 11 and ground contact surface 12. Upper 70 is located above sole 10 and has a shape that covers almost the entire portion of the wearer's foot distal to the ankle when inserted into the shoe.

[0014] As shown in Figures 2 to 5, the sole 10 is divided along the front-to-back direction (the up-down direction in Figures 2 and 3, the left-to-right direction in Figures 4 and 5), which is a direction that coincides with the longitudinal direction of the wearer's foot when viewed in a plane, into a forefoot portion R1 configured to support the toes and tread of the wearer's foot, a midfoot portion R2 configured to support the arch of the wearer's foot, and a rearfoot portion R3 configured to support the heel of the wearer's foot.

[0015] Taking the front end of the sole 10 as a reference, the position corresponding to 40% of the longitudinal dimension of the sole 10 from the front end is defined as the first boundary position, and the position corresponding to 60% of the longitudinal dimension of the sole 10 from the front end is defined as the second boundary position.The forefoot R1 corresponds to the portion included between the front end and the first boundary position along the longitudinal direction, the midfoot R2 corresponds to the portion included between the first boundary position and the second boundary position along the longitudinal direction, and the rearfoot R3 corresponds to the portion included between the second boundary position and the rear end of the sole along the longitudinal direction.

[0016] 2, the sole 10 is divided along the left-right direction (left-right direction in the figure), which is the direction that corresponds to the width direction of the wearer's foot when viewed in a plan view, into an inner foot portion (the portion on the S1 side shown in the figure) that is on the midline side (i.e., the side closer to the midline) of the anatomical orthostatic position of the foot, and an outer foot portion (the portion on the S2 side shown in the figure) that is on the opposite side from the midline side of the anatomical orthostatic position of the foot (i.e., the side farther from the midline). The left-right direction is a direction that intersects with the front-to-rear direction described above.

[0017] The boundary line dividing the sole 10 into an inner portion and an outer portion is the so-called shoe center SC. The shoe center SC is a line obtained by projecting a line connecting the area between the first and second toes of a standard wearer with a foot size that fits the shoe 100 and the center of the calcaneus (the so-called heel center (the heel center is indicated by the symbol HC in Figure 2 and other figures)) onto the sole 10 in the up-down direction when the shoe is worn by the standard wearer. The front end and rear end of the sole 10 described above are the ends of the sole 10 located on this shoe center SC.

[0018] 1, the upper 70 has an upper body 71, a shoe tongue 72, and shoelaces 73. The shoe tongue 72 and shoelaces 73 are both fixed or attached to the upper body 71.

[0019] An upper opening is provided at the top of the upper body 71, exposing the upper part of the ankle and part of the instep of the wearer. A lower opening is provided at the bottom of the upper body 71, which is covered by the sole 10. Note that a bottom may be formed at the bottom of the upper body 71 by, for example, sealing the lower end of the upper body 71.

[0020] The shoe tongue 72 is fixed to the upper body 71 by sewing, welding, bonding, or a combination of these, etc., so as to cover the portion of the upper opening provided in the upper body 71 that exposes part of the instep of the wearer. For example, woven fabric, knitted fabric, nonwoven fabric, synthetic leather, resin, etc. are used for the upper body 71 and the shoe tongue 72. For shoes that require particular breathability and lightness, the upper body 71 and the shoe tongue 72 are made of double raschel warp knitted fabric in which polyester yarn is woven.

[0021] The shoelaces 73 are string-like members that draw together the periphery of an upper opening in the upper body 71, which exposes a portion of the instep of the wearer, in the width direction of the wearer's foot. The shoelaces 73 are inserted through a plurality of holes provided around the periphery of the upper opening. By tightening the shoelaces 73 with the wearer's foot inserted into the upper body 71, the upper body 71 can be fitted closely to the wearer's foot.

[0022] 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 .

[0023] The midsole 20 is disposed on the upper part of the sole 10. The outsole 60 is disposed on the lower part of the sole 10. The plate 50 is embedded inside the midsole 20.

[0024] The midsole 20 is the base of the sole 10 and is located continuously from the forefoot portion R1 to the rearfoot portion R3 via the midfoot portion R2. The midsole 20 has a generally flat, plate-like shape and is configured to be relatively thicker than both the outsole 60 and the plate 50.

[0025] 6 to 10 , the midsole 20 has a base portion 30 and a cover portion 40. The base portion 30 is a portion that defines a lower portion of the midsole 20. The cover portion 40 is a portion that defines an upper portion of the midsole 20. In this embodiment, the base portion 30 and the cover portion 40 are configured as separate bodies.

[0026] The base portion 30 is located closer to the ground surface 12 than the plate 50 in the vertical direction, which is a direction perpendicular to the ground surface 12. The cover portion 40 covers the plate 50 by being located on the opposite side of the plate from the ground surface 12 in the vertical direction (i.e., on the upper 70 side). This results in the cover portion 40, which has a relatively low hardness, being interposed between the sole of the wearer's foot and the plate 50. Therefore, the wearer can be provided with a better wearing comfort than if the plate 50 were exposed toward the sole of the wearer's foot.

[0027] The base portion 30 includes an upper surface 31, a lower surface 32 located opposite the upper surface 31, a medial side surface of the foot, and a lateral side surface of the foot. The upper surface 31 of the base portion 30 faces the plate 50.

[0028] A cutout portion 32a consisting of a hole that penetrates from the lower surface 32 of the base portion 30 to the upper surface 31 is provided in the center in the left-right direction of the lower surface 32 of the base portion 30 at the part located in the midfoot portion R2. When viewed in the up-down direction, the cutout portion 32a extends in the front-to-rear direction.

[0029] As a result, in the portion of the base 30 located in the midfoot region R2, the rigidity of the medial portion in the left-right direction can be made relatively lower than the rigidity of the lateral portion, and thus the deformability of the medial portion can be made higher than the deformability of the lateral portion. As a result, the sole 10 can be made to be highly stable, with excessive inward or outward collapse suppressed when landing, etc. Furthermore, by providing the cutout portion 32a as described above, the weight of the sole 10 can be reduced. Note that the cutout portion 32a does not necessarily have to be a hole, and may be a depression.

[0030] The cover part 40 includes an upper surface 41, a lower surface 42 located opposite the upper surface 41, an inner side surface on the foot side, and an outer side surface on the foot side. The upper surface 41 of the cover part 40 defines the support surface 11 of the sole 10 described above, and has a smoothly curved shape to fit the sole of the wearer's foot. The upper surface 41 of the cover part 40 is joined to the upper body 71, for example, by adhesive. In this way, the sole 10 is fixed to the upper 70 (see FIG. 1 ).

[0031] The lower surface 42 of the cover portion 40 faces the plate 50. A concave portion is provided on the lower surface 42 of the cover portion 40. This concave portion is a portion for receiving the plate 50. As a result, the plate 50 and the lower surface 42 of the cover portion 40 into which it 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.

[0032] The base portion 30 and the cover portion 40 that constitute the midsole 20 preferably have an appropriate strength and excellent cushioning properties. From this perspective, for example, a resin foam material containing a resin material as a main component and a foaming agent and a cross-linking agent as secondary components is used for the base portion 30 and the cover portion 40. 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 secondary components may be used.

[0033] Examples of the resin material that can be used include ethylene-vinyl acetate copolymer (EVA), polyolefin resin, thermoplastic polyurethane, thermoplastic polyamide elastomer (TPA, TPAE), thermoplastic polyester elastomer, etc. Examples of the rubber material that can be used include butadiene rubber.

[0034] As a result, the base portion 30 and the cover portion 40 are generally made of soft materials with a small Young's modulus, and therefore the midsole 20 made of these components elastically deforms relatively easily when subjected to a compressive load, resulting in excellent cushioning properties.

[0035] 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. The method for measuring the hardness of each member constituting the sole 10 and the compressive modulus of elasticity, which is correlated therewith, will also be described in detail later.

[0036] The plate 50 is positioned continuously from the forefoot portion R1 to the rearfoot portion R3 via the midfoot portion R2. The plate 50 is configured to be relatively thinner than the midsole 20. The plate 50 is embedded inside the midsole 20 by being sandwiched between the base portion 30 and the cover portion 40 in the vertical direction.

[0037] The plate 50 has the functions of increasing the bending rigidity of the sole 10, applying a load uniformly to the base portion 30, which is the portion located below the plate 50, and increasing the forward propulsion force when pushing off by suppressing the dorsiflexion that occurs in the sole 10 when running.

[0038] The plate 50 is made of a material that is harder than the material that makes up the midsole 20. Suitable materials that can be used to make up the plate 50 include, for example, fiber-reinforced resins that use reinforcing fibers such as carbon fiber, glass fiber, aramid fiber, Dyneema fiber (registered trademark), Zylon fiber (registered trademark), and boron fiber, or non-foam materials made of non-fiber-reinforced resins made of polymer resins such as urethane-based thermoplastic elastomer (TPU), TPA, and EVA.

[0039] As shown in Figure 10 and Figure 12 described below, the plate 50 in the portion supporting the heel of the wearer's foot (i.e., the portion located in the rear foot region R3) has a bifurcated shape extending from the front to the rear. One of the bifurcated portions extends along the periphery of the sole 10 on the medial side of the foot. The other of the bifurcated portions extends along the periphery of the sole 10 on the lateral side of the foot. No plate 50 is located between the bifurcated portions.

[0040] This allows the rigidity of the medial portion of the plate 50 located in the rear foot region R3 to be relatively lower than that of the lateral portion, thereby increasing the deformability of the medial portion compared to the lateral portion, resulting in a sole 10 with excellent stability that is prevented from excessive inward or outward tipping when landing, etc.

[0041] The outsole 60 is mainly assembled to the midsole 20 and has a generally flat, plate-like shape. The outsole 60 is configured to be relatively thinner than the midsole 20.

[0042] The outsole 60 includes an upper surface 61 and a lower surface 62. The upper surface 61 of the outsole 60 covers most of the lower surface 32 of the base portion 30 and is joined to the lower surface 32 of the base portion 30 by adhesive or the like. The lower surface 62 of the outsole 60 defines the ground contact surface 12 of the sole 10 described above.

[0043] As shown in Figure 3, the outsole 60 is located continuously from the forefoot portion R1 to the rearfoot portion R3 via the midfoot portion R2. As described above, a cutout portion 32a is provided in the left-right central portion of the underside 32 of the base portion 30 in the portion located in the midfoot portion R2. Therefore, the portion of the outsole 60 located from the midfoot portion R2 to the rearfoot portion R3 has a bifurcated shape from the front to the rear so as to avoid the cutout portion 32a. One of the bifurcated portions extends along the periphery of the sole 10 on the medial side of the foot. The other of the bifurcated portions extends along the periphery of the sole 10 on the lateral side of the foot.

[0044] From another perspective, the outsole 60 includes a first portion 65 located in the forefoot region R1, a second portion 66 located in the midfoot region R2, and a third portion 67 located in the rearfoot region R3. The first portion 65 is located over the entire forefoot region R1. The second portion 66 is located on the medial side and lateral side of the midfoot region R2, as well as in the central region excluding the portion corresponding to the missing portion 32a. The third portion 67 is located on the medial side and lateral side of the rearfoot region R3. The second portion 66 connects the first portion 65 and the third portion 67.

[0045] With this configuration, the ground contact surface 12 defined by the underside 62 of the outsole 60 is formed continuously from the forefoot portion R1 to the rearfoot portion R3 on the medial and lateral peripheries of the sole 10. This increases the rigidity of the medial and lateral peripheries accordingly, effectively preventing excessive inward or outward tipping when the wearer runs (particularly when landing).

[0046] 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. This provides a tread pattern to the outsole 60, thereby improving the grip of the outsole 60. Furthermore, the weight of the outsole 60 is reduced.

[0047] An opening 62b is provided in the outsole 60 in a portion located on the lateral side of the forefoot R1 and corresponding to the toes of the wearer's foot, and extends from the upper surface 61 to the lower surface 62 of the outsole 60. The opening 62b extends along the lateral peripheral edge of the sole 10. When the outsole 60 is viewed from above, the size of the opening 62b is configured to be considerably larger than the size of each of the plurality of through-holes 62a.

[0048] Providing the opening 62b in the outsole 60 effectively prevents the wearer's center of gravity from shifting excessively toward the outside of the foot when pushing off, thereby achieving a smooth movement of the center of gravity from rear to front during the series of movements from landing to pushing off.

[0049] The outsole 60 is made of a material that is lower in hardness than the material that makes up the plate 50 but harder in hardness than the material that makes up the midsole 20. Furthermore, it is preferable that the outsole 60 have excellent abrasion resistance and grip. From these viewpoints, the material that makes up the outsole 60 is, for example, a member made of a material that contains a rubber material as a main component and a plasticizer, a reinforcing agent, and a cross-linking agent as secondary components. Butadiene rubber, for example, can be suitably used as this rubber material. As a result, the outsole 60 is generally made of a hard material that has a large Young's modulus. Therefore, the outsole 60 has excellent durability, such as abrasion resistance.

[0050] FIG. 11 is a schematic diagram showing the arrangement of the high hardness portion and the low hardness portion of the base portion of the sole shown in FIG. 1 . FIG. 12 is a schematic diagram showing the arrangement of the base portion and the plate of the sole shown in FIG. 1 . FIGS. 13 and 14 are both schematic cross-sectional views illustrating the state of the sole shown in FIG. 1 at the time of kicking off. Next, with reference to FIGS. 11 to 14 and the above-mentioned FIGS. 6 to 10 , details of the base portion 30 of the midsole 20 provided in the sole 10 according to this embodiment and the relationship between the base portion 30 and the plate 50 will be described. Note that FIG. 13 is a schematic cross-sectional view taken along line VI-VI in FIG. 2 . FIG. 14 is a schematic cross-sectional view taken along line VII-VII in FIG. 2 . For ease of understanding, in FIG. 11 , the high hardness portion 33 of the base portion 30 is dark-colored, and the low hardness portion of the base portion 30 is light-colored. 12, the first region 51 of the plate 50 is shaded darkly, and the second region 52 of the plate 50 is shaded lightly (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.

[0051] 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 portion having a predetermined hardness. The low-hardness portion 36 is a portion having a lower hardness than the high-hardness portion 33.

[0052] The high hardness portion 33 has a generally flat, plate-like shape and includes an upper surface 34 and a lower surface 35 located opposite the upper surface 34. Most of the upper surface 34 of the high hardness portion 33 faces the plate 50. The low hardness portion 36 has a generally flat, plate-like shape and includes an upper surface 37 and a lower surface 38 located opposite the upper surface 37. Most of the upper surface 37 of the low hardness portion 36 faces the plate 50.

[0053] In this embodiment, the low hardness portion 36 defines a part of the base portion 30 located in the forefoot region R1. The high hardness portion 33 defines the rest of the base portion 30 other than the part defined by the low hardness portion 36.

[0054] 6, 7, and 10, a recessed portion is provided in a portion of the upper surface 34 of the high hardness portion 33 that is located in the forefoot region R1. In a plan view, the outer shape of this recessed portion is configured to be substantially the same as the outer shape of the low hardness portion 36. This recessed portion is a portion for receiving the low hardness portion 36. The low hardness portion 36 is assembled to the high hardness portion 33 by fitting into this recessed portion.

[0055] 11 , the upper surface 31 of the base portion 30 includes a high hardness region 33a defined by an upper surface 34 of the high hardness portion 33 and a low hardness region 36a defined by an upper surface 37 of the low hardness portion 36. A lower surface 38 of the low hardness portion 36 is covered by a portion of the high hardness portion 33 other than the portion that defines the high hardness region 33a.

[0056] When viewed in the vertical direction (the direction perpendicular to the paper surface in FIG. 11 ), the low hardness region 36a is positioned approximately in the center of the forefoot R1 in both the front-to-back and left-to-right directions so that the portion supporting the sole of the wearer's MP joint (the portion indicated by the symbol MP in the figure) crosses the low hardness region 36a. The high hardness regions 33a are positioned in the midfoot R2 and rearfoot R3, and in the forefoot R1 in a portion other than the portion where the low hardness region 36a is located. Therefore, in this embodiment, when viewed in the vertical direction, the low hardness region 36a is surrounded by the high hardness region 33a.

[0057] By positioning the low hardness region 36a in the forefoot portion R1, a smooth shift of the center of gravity from rear to front during kicking is achieved, thereby providing propulsive force from rear to front.

[0058] 12 , a plate 50 is disposed on the upper surface 31 of the base portion 30. The plate 50 is positioned so as to straddle the high hardness region 33 a and the low hardness region 36 a. As a result, when viewed in the up-down direction, the plate 50 includes a first region 51 overlapping the high hardness region 33 a and a second region 52 overlapping the low hardness region 36 a. The boundary between the first region 51 and the second region 52 extends in a direction substantially parallel to the left-right direction.

[0059] The plate 50 includes a forefoot-side plate 50a located on the forefoot R1 side in the front-to-back direction (the up-and-down direction in FIG. 12 ) and a rearfoot-side plate 50b located on the rearfoot R3 side. More specifically, when the front end of the plate 50 is taken as a reference point and a position corresponding to 50% of the front-to-back dimension of the plate 50 from the front end is taken as a front-to-back boundary position, the forefoot-side plate 50a corresponds to the portion included between the front end and the front-to-back boundary position along the front-to-back direction, and the rearfoot-side plate 50b corresponds to the portion included between the front-to-back boundary position and the rear end of the plate 50 along the front-to-back direction.

[0060] The proportion of the second region 52 in the forefoot side plate 50a is higher than the proportion of the second region 52 in the rearfoot side plate 50b. In addition, when the rearfoot side plate 50b does not include the second region 52, as in the present embodiment, the proportion of the second region 52 in the rearfoot side plate 50b is zero.

[0061] A first imaginary plane V1 is an imaginary plane that passes through a position 20% of the total length of the sole 10 from the forward end of the shoe center SC of the sole 10 and is perpendicular to the shoe center SC of the sole 10. A second imaginary plane V2 is an imaginary plane that passes through a position 60% of the total length of the sole 10 from the forward end of the shoe center SC of the sole 10 and is perpendicular to the shoe center SC of the sole 10. In this case, the frontmost end position P1 of the first region 51 in the front-to-rear direction is located within a range R12 sandwiched between the first imaginary plane V1 and the second imaginary plane V2. The portion of the plate 50 forward of the frontmost end position P1 of the first region 51 is formed by the second region 52. The rearmost end position P2 of the second region 52 in the front-to-rear direction is located rearward of the frontmost end position P1 of the first region 51.

[0062] Furthermore, in the front end base portion 30a, which is a portion of the base portion 30 located forward of the foremost position P1 of the first region 51, the high hardness region 33a includes an inner foot side portion 33a1 and an outer foot side portion 33a2. The inner foot side portion 33a1 is a portion of the high hardness region 33a that is arranged along the inner foot side peripheral edge of the sole 10. The outer foot side portion 33a2 is a portion of the high hardness region 33a that is arranged along the outer foot side peripheral edge of the sole 10.

[0063] The low hardness region 36a is located between the medial portion 33a1 and the lateral portion 33a2. Furthermore, both left-right edges of the plate 50 are located more inward than both the medial portion 33a1 and the lateral portion 33a2 in the forefoot base portion 30a. More specifically, when viewed from the top-bottom direction, both left-right edges of the plate 50 are located more inward than both left-right edges of the low hardness region 36a. This allows the forefoot plate 50a to sink downward more easily.

[0064] With the above-described configuration, the sole 10 can be made to improve the propulsive force at the time of kicking off, thereby enabling efficient running. This point will be described in detail below.

[0065] 13 and 14, when the wearer steps off, a load is applied intensively from the sole of the wearer's foot at a portion corresponding to the MP joint toward the sole 10. As a result, a particularly large compressive load is applied to the portion of the midsole 20 that supports the sole of the foot at the portion corresponding to the MP joint and the surrounding area. Furthermore, the load associated with the stepping is also applied to the plate 50 embedded inside the midsole 20. The forefoot side plate 50a includes a portion to which the load associated with the stepping is applied.

[0066] Here, in this embodiment, as described above, the sole 10 is configured so that the proportion of the second region 52 in the forefoot side plate 50a is higher than the proportion of the second region 52 in the rearfoot side plate 50b.

[0067] This configuration allows the forefoot plate 50a to sink downward more easily than the rearfoot plate 50b, so that when the load is applied to the plate 50, the forefoot plate 50a can be elastically deformed to bend significantly downward.

[0068] When the forefoot plate 50a is elastically deformed so as to bend downward in this manner, a propulsive force from the rear to the front can be obtained by the repulsive force generated by the elastically deformed forefoot plate 50a. A smooth shift of the center of gravity from the rear to the front can also be achieved, thereby generating propulsive force. As a result, propulsive force is improved when pushing off, resulting in a sole 10 that allows for efficient running.

[0069] Therefore, by using the sole 10 of the present embodiment described above and the shoe 100 equipped with the same, it is possible to improve the propulsion force when pushing off, thereby achieving efficient running.

[0070] In the present embodiment, as described above, the portion of the plate 50 located across the high hardness region 33a and the low hardness region 36a that is forward of the foremost end position P1 of the first region 51 is configured by the second region 52. That is, when focusing on the foremost end position P1 and its vicinity, the portion of the plate 50 that is rearward of the foremost end position P1 is supported by the high hardness region 33a, which has a relatively high hardness, and the portion of the plate 50 that is forward of the foremost end position P1 is supported by the low hardness region 36a, which has a relatively low hardness.

[0071] With this configuration, when the load is applied to the plate 50, the portion of the first region 51 forward of the front end position P1 can be elastically deformed so as to bend significantly downward.

[0072] Even when the front portion of the plate 50 is elastically deformed so as to bend downward in this manner, a propulsive force from the rear to the front can be obtained by the repulsive force generated by the elastically deformed plate 50. Furthermore, a smooth movement of the center of gravity from the rear to the front can be achieved, which also makes it possible to obtain a propulsive force.

[0073] Here, from the viewpoint of ensuring the maximum repulsive force of the plate 50, it is preferable that the portion of the plate 50 located below at least the MP joint and its surrounding area of ​​the sole of the wearer's foot be constituted by the second region 52. In other words, it is preferable that the front end position P1 of the first region 51 be located rearward of a predetermined position in the front-to-rear direction.

[0074] Furthermore, from the viewpoint of realizing a smoother shift of the center of gravity from the rear to the front, it is preferable that the portion of the plate 50 that elastically deforms as described above be located appropriately biased forward. In other words, it is preferable that the frontmost position P1 of the first region 51 be located forward of a predetermined position in the fore-and-aft direction.

[0075] In this regard, in the present embodiment, as described above, the front end position P1 of the first region 51 is located within the range R12 between the first imaginary plane V1 and the second imaginary plane V2. With this configuration, it is possible to obtain both the propulsive force resulting from the repulsive force of the plate 50 described above and the propulsive force resulting from the smooth movement of the center of gravity from the rear to the front.

[0076] Furthermore, in this embodiment, as described above, the low hardness region 36a is located in the front-end base portion 30a between the medial portion 33a1 and the lateral portion 33a2 of the high hardness region 33a. By making the medial portion of the top surface 31 of the front-end base portion 30a lower in hardness than the lateral portion, the rigidity of the medial portion can be made relatively lower than the rigidity of the lateral portion. As a result, excessive inward or outward tipping during the series of movements from landing to pushing off is suppressed, resulting in a sole 10 that allows for a smooth shift of the center of gravity from rear to front.

[0077] As described above, both edges of the plate 50 in the left-right direction at the front end base portion 30a are located more inward than both the medial foot side portion 33a1 and the lateral foot side portion 33a2. This allows the plate 50 to be positioned so as to bridge the medial foot side portion 33a1 and the lateral foot side portion 33a2, thereby preventing the aforementioned flexural deformation of the front portion of the plate 50 from being hindered. This allows the sole 10 to have improved propulsion force during push-off.

[0078] Furthermore, in this embodiment, as described above, the boundary between the first region 51 and the second region 52 of the plate 50 extends in a direction substantially parallel to the left-right direction. This configuration allows the above-described flexural deformation of the front portion of the plate 50 to occur more evenly in the left-right direction. This allows the sole 10 to have improved stability during push-off.

[0079] In addition, in this embodiment, as described above, the rearmost end position P2 of the second region 52 is located rearward of the frontmost end position P1 of the first region 51. This configuration allows for a smoother movement of the center of gravity from rear to front during kicking.

[0080] Although the above-described embodiment has been described by way of example with reference to a case where the midsole 20 is configured with the base portion 30 and the cover portion 40 formed separately from each other, the midsole 20 may be configured with the base portion 30 and the cover portion 40 formed as an integral unit. In this case, for example, by inserting the plate 50 during the cast molding or injection molding of the midsole 20, the midsole 20 can have the plate 50 embedded therein.

[0081] Furthermore, in the above-described embodiment, the base portion 30 and cover portion 40 constituting the midsole 20 are explained as being made of a resin foam material, but the base portion 30 and cover portion 40 may also be made of a shaped object produced by, for example, a three-dimensional additive manufacturing method using a photolithography method.

[0082] Furthermore, in the above-described embodiment, an example has been given in which the rearmost end position P2 of the second region 52 in the fore-and-aft direction is located rearward of the frontmost end position P1 of the first region 51, but the rearmost end position P2 may also be located at a position corresponding to the frontmost end position P1 of the first region 51 in the fore-and-aft direction.

[0083] <Hardness Measurement> The hardness of each component constituting the 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 specimen having a specified thickness or greater is prepared. Next, the test specimen is placed on a flat surface. Next, the pressure surface of the durometer is pressed against the test specimen so that the indenter is perpendicular to the measurement surface of the test specimen. The instantaneous value obtained when the pressure surface is pressed against the test specimen is taken as the measured hardness of the test specimen. The above measurement is performed five times so that the contact points of the indenter are at least 6 mm apart from each other, and the median of the five measured values ​​obtained is taken as the hardness of the test specimen. Note that if the thickness of the test specimen is less than the specified value, test specimens of the same type may be stacked.

[0084] The base portion 30 of the midsole 20 is preferably one in which the hardness of the low hardness portion 36 is at least 8 degrees lower than the hardness of the high hardness portion 33, but is not particularly limited to this. The hardness of the base portion 30 of the midsole 20 is measured using a Type C durometer (Asker C type) in accordance with JIS K6253.

[0085] The outsole 60 has a hardness of 50 or more and 80 or less, for example, and the plate 50 has a hardness of 60 or more, for example. The hardness of the outsole 60 is measured by a Type A durometer (Asker Type A) in accordance with JIS K6253. The hardness of the plate 50 is measured by a Type D durometer (Asker Type D) in accordance with JIS K6253.

[0086] <Measurement of Compressive Elastic Modulus> Generally, there is a correlation between the hardness and compressive elastic modulus of a member such that the higher the hardness, the higher the compressive elastic modulus, and the lower the hardness, the lower the compressive elastic modulus.

[0087] The compressive modulus of each component constituting the sole 10 is measured using a measurement method conforming to the compression test (Method A) of JIS K6254:2016, as described below. More specifically, a cylindrical test specimen with a thickness of 12 mm to 13 mm and a diameter of 28.5 mm to 29.5 mm is first prepared. Next, lubricating oil is applied to a pair of metal plates of the compression tester. Next, the test specimen is compressed by being sandwiched between the pair of metal plates from both sides in a direction corresponding to the up-down direction, which is perpendicular to the ground contact surface 12. The compressive force is released when the strain of the test specimen reaches 25% due to this compression. The initial slope of the stress-strain curve of the test specimen obtained by this compression, up to the strain of 5%, is calculated as the compressive modulus of the test specimen.

[0088] The base portion 30 of the midsole 20 is configured such that the compressive modulus of the low hardness portion 36 is lower than the compressive modulus of the high hardness portion 33. The compressive modulus of the low hardness portion 36 is preferably 0.25 times or more and less than 1.0 times the compressive modulus of the high hardness portion 33. More preferably, the compressive modulus of the low hardness portion 36 is 0.3 times or more and less than 0.75 times the compressive modulus of the high hardness portion 33.

[0089] <First Modification> Fig. 15 is a schematic diagram showing the arrangement of the base portion and plate of a shoe sole according to a first modification. Hereinafter, a shoe sole 10A according to the first modification based on the embodiment described above will be described with reference to Fig. 15 .

[0090] As shown in FIG. 15, a sole 10A according to the first modification is different from the sole 10 according to the above-described embodiment only in the shape of the plate 50.

[0091] More specifically, in this modification, one of the two left-right edges of the plate 50 is positioned so as to overlap the boundary between the low hardness region 36a and the medial portion 33a1 of the high hardness region 33a, and the other of the two left-right edges of the plate 50 is positioned so as to overlap the boundary between the low hardness region 36a and the lateral portion 33a2 of the high hardness region 33a.

[0092] Even when configured in this manner, the same effects as those described in the above-mentioned embodiment can be obtained, and a sole and shoes equipped with the same can be provided that can achieve efficient running by improving propulsion force when kicking off.

[0093] <Second Modification> Fig. 16 is a schematic diagram showing the arrangement of the base and plate of a sole according to a second modification. Below, a sole 10B according to the second modification based on the above-described embodiment will be described with reference to Fig. 16.

[0094] As shown in FIG. 16, a sole 10B according to the second modification differs from the sole 10 according to the above-described embodiment only in the configuration of the base portion 30.

[0095] More specifically, in this 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 itself.

[0096] Even when configured in this manner, the same effects as those described in the above-mentioned embodiment can be obtained, and a sole and shoes equipped with the same can be provided that can achieve efficient running by improving propulsion force when kicking off.

[0097] <Third Modification> Fig. 17 is a schematic diagram showing the arrangement of the base portion and the plate of a shoe sole according to a third modification. Hereinafter, a shoe sole 10C according to the third modification based on the above-described embodiment will be described with reference to Fig. 17 .

[0098] As shown in FIG. 17, a sole 10C according to the third modification differs from the sole 10 according to the above-described embodiment only in the configuration of the base portion 30.

[0099] More specifically, in this modified example, the base portion 30 is configured so that the rear end of the low hardness portion 36 of the base portion 30 is located in the midfoot portion R2.

[0100] Even when configured in this manner, the same effects as those described in the above-mentioned embodiment can be obtained, and a sole and shoes equipped with the same can be provided that can achieve efficient running by improving propulsion force when kicking off.

[0101] <Fourth Modification> Fig. 18 is a schematic diagram showing the arrangement of the base portion and the plate of a shoe sole according to a fourth modification. Hereinafter, a shoe sole 10D according to the fourth modification based on the above-described embodiment will be described with reference to Fig. 18 .

[0102] As shown in FIG. 18, a sole 10D according to the fourth modification differs from the sole 10 according to the above-described embodiment only in the configuration of the base portion 30.

[0103] More specifically, in this modified example, the base portion 30 is configured so that the rear end of the low hardness portion 36 of the base portion 30 is located in the rearfoot region R3.

[0104] Even when configured in this manner, the same effects as those described in the above-mentioned embodiment can be obtained, and a sole and shoes equipped with the same can be provided that can achieve efficient running by improving propulsion force when kicking off.

[0105] <Fifth Modification> Fig. 19 is a schematic diagram showing the arrangement of the base portion and the plate of a shoe sole according to a fifth modification. Hereinafter, a shoe sole 10E according to the fifth modification based on the above-described embodiment will be described with reference to Fig. 19 .

[0106] As shown in FIG. 19, a sole 10E according to the fifth modification differs from the sole 10 according to the above-described embodiment only in the configuration of the base portion 30.

[0107] More specifically, in this modified example, the base portion 30 is configured so that the low hardness portion 36 defines almost the entire portion of the base portion 30 located in the forefoot region R1.

[0108] Even when configured in this manner, the same effects as those described in the above-mentioned embodiment can be obtained, and a sole and shoes equipped with the same can be provided that can achieve efficient running by improving propulsion force when kicking off.

[0109] <Sixth Modification> Fig. 20 is a schematic diagram showing the arrangement of the base and plate of a shoe sole according to a sixth modification. Hereinafter, a shoe sole 10F according to the sixth modification based on the above-described embodiment will be described with reference to Fig. 20.

[0110] As shown in FIG. 20, a sole 10F according to the sixth modification is different from the sole 10 according to the above-described embodiment only in the shape of the plate 50.

[0111] More specifically, in this modification, the plate 50 is configured so 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 rear end of the low hardness portion 36.

[0112] Even when configured in this manner, the same effects as those described in the above-mentioned embodiment can be obtained, and a sole and shoes equipped with the same can be provided that can achieve efficient running by improving propulsion force when kicking off.

[0113] <Seventh Modification> Fig. 21 is a schematic cross-sectional view of a shoe sole according to a seventh modification. Hereinafter, a shoe sole 10G according to the seventh modification based on the above-described embodiment will be described with reference to Fig. 21 .

[0114] As shown in FIG. 21, a sole 10G according to the seventh modification differs from the sole 10 according to the above-described embodiment only in the configuration of the base portion 30.

[0115] More specifically, in this modification, the low hardness portion 36 extends from the upper surface 31 to the lower surface 32 of the base portion 30. Therefore, in this modification, the upper surface 34 of the high hardness portion 33 does not have the above-described recessed portion for receiving the low hardness portion 36.

[0116] Even when configured in this manner, the same effects as those described in the above-mentioned embodiment can be obtained, and a sole and shoes equipped with the same can be provided that can achieve efficient running by improving propulsion force when kicking off.

[0117] <Aspects> The features disclosed in the above-described embodiment and its modifications can be summarized as follows.

[0118] [Aspect 1] A shoe sole according to one aspect of the present disclosure is a shoe sole having a ground contact surface and including a forefoot portion configured to support the toes and forefoot of a wearer's foot, a midfoot portion configured to support the arch of the wearer's foot, and a rearfoot portion configured to support the heel of the wearer's foot, which are connected along a front-to-rear direction that intersects with a left-right direction that coincides with a foot width direction of the wearer's foot and coincides with a foot length direction of the wearer's foot; the sole comprises: a sole body positioned continuously from the forefoot portion to the rearfoot portion; and a plate positioned continuously from the forefoot portion to the rearfoot portion and made of a material having a higher hardness than a material constituting the sole body; the sole body having a base portion positioned closer to the ground contact surface than the plate in a direction perpendicular to the ground contact surface, the base portion including an upper surface facing the plate and a lower surface positioned opposite the upper surface; the base portion including a high hardness portion having a predetermined hardness and a low hardness portion having a lower hardness than 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 arranged on the upper surface of the base portion so as to span the high hardness region and the low hardness region; the plate includes, when viewed along a direction perpendicular to the ground surface, a first region overlapping the high hardness region and a second region overlapping the low hardness region; the plate includes, in the front-to-rear direction, a forefoot side plate located on the forefoot side and a rearfoot side plate located on the rearfoot side; and the proportion of the second region in the forefoot side plate is higher than the proportion of the second region in the rearfoot side plate.

[0119] By configuring in this way, it is possible to improve the propulsive force at the time of kicking off, thereby realizing efficient running.

[0120] [Aspect 2] In the sole described in Aspect 1, when an imaginary plane that passes from the forward end of the shoe center of the sole to a position that is 20% of the total length of the sole and is perpendicular to the shoe center of the sole is defined as a first imaginary plane, and an imaginary plane that passes from the forward end of the shoe center of the sole to a position that is 60% of the total length of the sole and is perpendicular to the shoe center of the sole is defined as a second imaginary plane, the foremost end position of the first region in the front-to-rear direction may be located within a range sandwiched between the first imaginary plane and the second imaginary plane, and a portion of the plate that is forward of the foremost end position of the first region may be configured as the second region.

[0121] This configuration makes it possible to obtain maximum thrust from both the repulsive force of the plate and the smooth movement of the center of gravity from rear to front.

[0122] [Aspect 3] In the sole described in Aspect 2, the rearmost position in the front-to-rear direction of the second region may be a position corresponding to the frontmost position of the first region in the front-to-rear direction, or may be located rearward of the frontmost position of the first region.

[0123] This configuration allows for smoother movement of the center of gravity from rear to front when kicking off.

[0124] [Aspect 4] In the sole according to Aspects 2 or 3, in a front base portion of the base that is located forward of the foremost position of the first region, the high hardness region may include an inner portion disposed along the inner periphery of the sole and an outer portion disposed along the outer periphery of the sole, and the low hardness region may be located between the inner portion and the outer portion. In this case, both end edges of the plate in the left-right direction may be located more inward than both the inner portion and the outer portion in the front base portion, or one of the end edges of the plate in the left-right direction may overlap the boundary between the inner portion and the low hardness region, and the other may overlap the boundary between the outer portion and the low hardness region.

[0125] By configuring it in this way, the plate is positioned so as to bridge the medial and lateral foot portions, thereby preventing the above-mentioned flexural deformation of the front portion of the plate from being hindered.

[0126] [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 in a direction perpendicular to the ground contact surface.

[0127] With this configuration, the low hardness regions can be formed in spots on the upper surface of the base portion.

[0128] [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 left-right direction.

[0129] This configuration allows the aforementioned flexural deformation of the front portion of the plate to occur more evenly in the left-right direction, resulting in a sole with improved stability when pushing off.

[0130] [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 by a portion of the high hardness portion other than the portion that defines the high hardness region. By configuring in this manner, it is possible to impart appropriate rigidity to the base portion.

[0131] [Aspect 8] In the shoe sole according to any one of Aspects 1 to 6, the low hardness portion may extend from the upper surface of the base portion to the lower surface of the base portion.

[0132] By configuring in this manner, the plate can be made to sink downward more easily in the second region.

[0133] [Aspect 9] In the sole according to any one of Aspects 1 to 8, a cutout portion consisting of either a recess or a hole may be provided in a central portion in the left-right direction of the underside of the base portion in the portion located in the midfoot region.

[0134] By configuring the sole in this way, the rigidity of the medial side of the base at the midfoot can be made relatively lower than that of the lateral side, and the deformability of the medial side can be made higher than that of the lateral side. As a result, the sole can be made more stable by suppressing excessive inward or outward collapse when landing, etc. Furthermore, this configuration also contributes to reducing the weight of the sole.

[0135] [Aspect 10] In the shoe sole according to any one of Aspects 1 to 9, the sole body may further include a cover portion that is positioned on the opposite side of the plate from the ground contact surface in a direction perpendicular to the ground contact surface, thereby covering the plate.

[0136] This configuration provides the wearer with a more comfortable fit than when the plate is exposed toward the sole of the wearer's foot.

[0137] [Aspect 11] In the shoe sole according to Aspect 10, the cover portion may be configured separately from the base portion. In this case, the plate may be embedded by being sandwiched between the base portion and the cover portion in a direction perpendicular to the ground surface.

[0138] By configuring in this way, it is possible to relatively easily form the sole body with the plate embedded therein.

[0139] [Aspect 12] In the shoe sole according to any one of Aspects 1 to 11, the plate in the portion supporting the heel of the wearer's foot may have a bifurcated shape extending from the front to the rear.

[0140] With this configuration, the rigidity of the medial portion of the plate supporting the heel of the wearer's foot in the left-right direction can be made relatively lower than that of the lateral portion, and the deformability of the medial portion can be made higher than that of the lateral portion, resulting in a sole with excellent stability that is prevented from excessive inward or outward collapse when landing, etc.

[0141] [Aspect 13] The sole of any one of Aspects 1 to 12 may further include an outsole that covers the lower surface of the base portion and defines the ground contact surface. In this case, it is preferable that the outsole be made of a material that is less hard than the material that constitutes the plate but harder than the material that constitutes the sole body. Also, in this case, the outsole may include 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 may be located at least in the medial and lateral portions of the midfoot portion to connect the first and third portions.

[0142] With this configuration, the medial and lateral peripheries of the sole have a continuous ground contact surface defined by the underside of the outsole, extending from the forefoot to the rearfoot R. This increases the rigidity of the medial and lateral peripheries accordingly, effectively preventing excessive inward or outward tipping when the wearer runs (particularly when landing).

[0143] [Aspect 14] In the sole according to Aspect 13, an opening may be provided in the outsole at a portion located on the lateral side of the forefoot portion and corresponding to the toes of the wearer's foot.

[0144] This configuration effectively prevents the wearer's center of gravity from shifting excessively toward the outside of the foot when pushing off, thereby achieving a smooth shift of the center of gravity from rear to front during the series of movements from landing to pushing off.

[0145] [Aspect 15] In the shoe sole according to any one of Aspects 1 to 14, the sole body may be made of a foam material made of resin or rubber.

[0146] By configuring it in this way, it is possible to obtain a sole body that has an appropriate strength and excellent shock-absorbing properties.

[0147] [Aspect 16] In the shoe sole according to any one of Aspects 1 to 15, the plate may be made of a non-foam resin material.

[0148] By configuring it in this way, the bending rigidity of the sole can be increased, and by suppressing the dorsiflexion that occurs in the sole when running, the forward propulsion force when pushing off can be increased.

[0149] [Aspect 17] A shoe according to one aspect of the present disclosure includes the sole according to any one of Aspects 1 to 16 above, and an upper provided above the sole.

[0150] By configuring in this way, it is possible to improve the propulsive force at the time of kicking off, thereby realizing efficient running.

[0151] <Other Configurations> The shapes and sizes of the midsole, outsole, and plate that make up the sole of the shoe can be modified in various ways without departing from the spirit of the present invention. In addition, the configuration and shape of the upper can also be modified in various ways.

[0152] Furthermore, the characteristic configurations shown in the above-described embodiment and its modifications can be combined with each other without departing from the spirit of the present invention.

[0153] As such, the above-described embodiments and their modifications disclosed herein are illustrative in all respects and are not restrictive. The technical scope of the present invention is defined by the claims, and includes all modifications within the meaning and scope of the claims.

[0154] 10, 10A to 10G Shoe sole, 11 Support surface, 12 Ground contact surface, 20 Midsole, 30 Base portion, 30a Front end base portion, 31 Upper surface, 32 Lower surface, 32a Missing portion, 33 High hardness portion, 33a High hardness region, 33a1 Medial foot side portion, 33a2 Lateral foot side 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 part, 70 Upper, 71 Upper body, 72 Shoe tongue, 73 Shoelace, 100 Shoe, R1 Forefoot portion, R2 Midfoot portion, R3 Rearfoot portion, SC Shoe center, V1 First imaginary plane, V2 Second imaginary plane.

Claims

1. A shoe sole having a ground contact surface, a forefoot section configured to support the toes and plantar fascia of a wearer's foot, a midfoot section configured to support the arch of the wearer's foot, and a rearfoot section configured to support the heel of the wearer's foot, which are connected along a front-to-rear direction that intersects with a left-right direction that corresponds to the width direction of the wearer's foot and corresponds to the length direction of the wearer's foot, the sole comprising: a sole body located continuously from the forefoot section to the rearfoot section; and a plate located continuously from the forefoot section to the rearfoot section and composed of a material having a higher hardness than a material constituting the sole body, the sole body having a base section located closer to the ground contact surface than the plate in a direction perpendicular to the ground contact surface, the base section including an upper surface facing the plate and a lower surface located on the opposite side to the upper surface, the base section including a high hardness section having a predetermined hardness and a low hardness section having a lower hardness than the high hardness section, a sole, wherein 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 a direction perpendicular to the ground contact surface, the plate includes a forefoot side plate located on the forefoot side and a rearfoot side plate located on the rearfoot side in the front-to-rear direction, and a proportion of the second region in the forefoot side plate is higher than a proportion of the second region in the rearfoot side plate.

2. The sole according to claim 1, wherein when an imaginary plane that passes from the forward end of the shoe center of the sole to a position that is 20% of the total length of the sole and is perpendicular to the shoe center of the sole is defined as a first imaginary plane, and an imaginary plane that passes from the forward end of the shoe center of the sole to a position that is 60% of the total length of the sole and is perpendicular to the shoe center of the sole is defined as a second imaginary plane, the foremost end position of the first region in the front-to-rear direction is located within a range sandwiched between the first imaginary plane and the second imaginary plane, and a portion of the plate that is forward of the foremost end position of the first region is constituted by the second region.

3. The sole of claim 2, wherein the rearmost end position of the second region in the front-to-rear direction is a position corresponding to the frontmost end position of the first region in the front-to-rear direction, or is located rearward of the frontmost end position of the first region.

4. A sole as described in claim 2, wherein, in a front end base portion which is a portion of the base portion located forward of the foremost position of the first region, the high hardness region includes an inner foot side portion arranged to follow the inner foot side peripheral edge of the sole and an outer foot side portion arranged to follow the outer foot side peripheral edge of the sole, and the low hardness region is located between the inner foot side portion and the outer foot side portion, and both end edges of the plate in the left-right direction are located more inward than either the inner foot side portion or the outer foot side portion in the front end base portion, or one of the both end edges of the plate in the left-right direction is located overlapping the boundary between the inner foot side portion and the low hardness region and the other is located overlapping the boundary between the outer foot side portion and the low hardness region.

5. The sole according to claim 1, wherein the low hardness region is surrounded by the high hardness region when viewed along a direction perpendicular to the ground contact surface.

6. The sole according to claim 1, wherein the boundary between the first region and the second region extends along a direction substantially parallel to the left-right direction.

7. The sole according to claim 1, wherein the lower surface of the low hardness portion is covered by a portion of the high hardness portion other than the portion that defines the high hardness region.

8. The sole according to claim 1, wherein the low hardness portion extends from the upper surface of the base portion to the lower surface of the base portion.

9. The sole of claim 1, wherein a cutout portion consisting of either a recess or a hole is provided in a central portion in the left-right direction of the underside of the base portion in the portion located in the midfoot region.

10. The sole of claim 1, wherein the sole body further has a cover portion that is positioned on the opposite side of the plate from the ground surface in a direction perpendicular to the ground surface, thereby covering the plate.

11. The sole of claim 10, wherein the cover portion is formed separately from the base portion, and the plate is embedded by being sandwiched between the base portion and the cover portion in a direction perpendicular to the ground surface.

12. The sole according to claim 1, wherein the plate in the portion supporting the heel of the wearer's foot has a bifurcated shape going from the front to the rear.

13. The sole of claim 1, further comprising an outsole covering the lower surface of the base portion and defining the ground contact surface, the outsole being made of a material that is less hard than a material constituting the plate but harder than a material constituting the sole body, the outsole including 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, the second portion being located at least in the medial and lateral portions of the midfoot portion so as to connect the first and third portions.

14. The sole according to claim 13, wherein an opening is provided in the outsole in a portion located on the lateral side of the forefoot portion and corresponding to the toes of the wearer's foot.

15. The sole of claim 1, wherein the sole body is made of a resin or rubber foam material.

16. The sole of claim 1, wherein the plate is made of a resin non-foam material.

17. A shoe comprising a sole according to any one of claims 1 to 16 and an upper provided above the sole.

Images