Patent Description:
Shoes having a plate disposed in a midsole have been known. For example, <CIT> discloses a sole structure including an outsole, a cushioning member disposed on the outsole, a midsole disposed on the cushioning member, and a footwear plate disposed between the cushioning member and the midsole. <CIT> describes an article of footwear having an embedded plate structure. <CIT> describes a midfoot structure of a sole assembly for a shoe. <CIT> describes a sole for an athletic shoe.

A plate according the claimed invention is defined in claim <NUM>. Dependent claims <NUM> and <NUM> define advantageous embodiments of the plate according to the claimed invention. A sole according to the claimed invention is defined in claim <NUM>. A shoe according to the claimed invention is defined in claim <NUM>. For the sole like the one disclosed in <CIT>, in order to enhance the impact cushioning property in the ground contact phase, the material forming the midsole may be reduced in weight and/or hardness. In this case, for the sake of preventing wearer's injury and/or maintaining good performance, the shoe is required to have higher stability. This object can be achieved for example by suppressing arch falling from the ground contact phase to the take-off phase, and suppressing excessive deformation of the midsole in the take-off phase.

An object of the present disclosure is to provide a plate, a sole, and a shoe that enable both the suppression of arch falling from the ground contact phase to the take-off phase and the suppression of excessive deformation of the midsole in the take-off phase.

A plate according to an aspect of the present disclosure is a plate to be used for a sole forming a part of a shoe. The plate includes: a front support portion that is formed at a position overlapping, in a thickness direction of the sole, MP joints of a wearer of the shoe, and supports a forefoot portion of the wearer; and a center support portion that has a shape extending rearward from the front support portion, is formed at a position overlapping, in the thickness direction of the sole, metatarsal bones of the wearer of the shoe, and supports at least a midfoot portion of the wearer. The front support portion is formed in a flat shape or a curved shape with a single downward protrusion in a cross section in a foot width direction, when the sole is placed on a flat plane. The center support portion has a shape with an upward protrusion and a downward protrusion arranged alternately in the foot width direction in a cross section in the foot width direction, when the sole is placed on the flat plane, wherein the upward protrusion has a shape curved to protrude upward and the downward protrusion has a shape curved to protrude downward.

A sole according to an aspect of the present disclosure includes: the plate; and a midsole forming a part of the sole. The midsole supports the plate in such a manner that, when the sole is placed on the flat plane, a boundary between the front support portion and the center support portion is located at a lowermost point of the plate and a part of the plate that is located rearward of the boundary has a posture separated gradually away from the flat plane, toward a rear in a longitudinal direction of the shoe.

A shoe according to an aspect of the present disclosure includes: the sole; and an upper connected to the sole and located over the sole.

Embodiments of the present disclosure are described with reference to the drawings. In the drawings referenced below, the same or corresponding parts are denoted by the same reference numerals. In the following description, terms such as foot length direction, foot width direction, frontward, rearward are used. Each of these terms representing a direction indicates the direction as seen from a viewpoint of a wearer of a shoe <NUM> placed on a flat plane P (see <FIG>) such as ground. For example, frontward refers to toward the toe and rearward refers to toward the heel. Moreover, inner side refers to the inner side (first-toe side) of the foot in the foot width direction, and outer side refers to the outer side of the foot in the foot width direction.

<FIG> is a perspective view schematically showing a plate to be used for a shoe, according to one embodiment of the present disclosure. <FIG> is a plan view showing a relation between a sole including a plate and foot bones of a wearer of a shoe. <FIG> is a cross-sectional view along a line III-III in <FIG>.

<FIG> shows a plate <NUM> for the left foot, and <FIG> shows a plate <NUM> for the right foot. These plates have respective shapes in bilateral symmetry with each other, or respective shapes nearly identical thereto. The same applies as well to soles <NUM> and shoes <NUM> including respective plates <NUM>. The shoe <NUM> according to the present embodiment is applicable for use as a sports shoe such as running shoe or a walking shoe, for example, and the use of the shoe <NUM> is not limited to them.

As shown in <FIG>, the shoe <NUM> includes the sole <NUM> and an upper <NUM>.

The upper <NUM> is connected to the sole <NUM> and located over the sole <NUM>. The upper <NUM> and the sole <NUM> together form a space for receiving a foot of a wearer.

As shown in <FIG>, the sole <NUM> includes an outsole <NUM>, a midsole <NUM>, and a plate <NUM>.

The outsole <NUM> forms a ground contact portion. The outsole <NUM> is made from rubber or the like.

The midsole <NUM> is placed over the outsole <NUM>. The midsole <NUM> is formed from a resin foam material or the like. The upper <NUM> is disposed on this midsole <NUM>. Namely, the midsole <NUM> is disposed between the upper <NUM> and the outsole <NUM>. As shown in <FIG>, the midsole <NUM> includes a forefoot region R1, a midfoot region R2, and a rearfoot region R3.

The forefoot region R1 is a region overlapping, in the thickness direction of the sole <NUM>, a forefoot portion of a wearer of the shoe <NUM>. The forefoot portion is a part of the foot of the wearer that is located frontward in the longitudinal direction of the shoe <NUM>, i.e., the foot length direction (top-to-bottom direction in <FIG>) of the shoe <NUM>. The forefoot region R1 is a region located to extend over a range of approximately <NUM>% to <NUM>% with respect to the total length of the shoe <NUM>, from the front end of the shoe <NUM> toward the rear end thereof.

The foot length direction is a direction parallel to a shoe center SC (see <FIG>). The shoe center SC is not limited to the centerline of the shoe <NUM>, but may be a line corresponding to a straight line connecting the calcaneus bone B30 of a standard wearer of the shoe <NUM> and a point between the first toe and the second toe of the wearer.

The midfoot region R2 is a region overlapping, in the thickness direction of the sole <NUM>, a midfoot portion of a wearer of the shoe <NUM>. The midfoot portion is a part of the foot of the wearer located centrally in the longitudinal direction. The midfoot region R2 is a region located to extend over a range of approximately <NUM>% to <NUM>% with respect to the total length of the shoe <NUM>, in the direction from the front end of the shoe <NUM> toward the rear end thereof.

The rearfoot region R3 is a region overlapping, in the thickness direction of the sole <NUM>, a rearfoot portion of a wearer of the shoe <NUM>. The rearfoot portion is a part of the foot of the wearer that is located rearward in the longitudinal direction. The rearfoot region R3 is a region located to extend over a range of <NUM>% to <NUM>% with respect to the total length of the shoe <NUM>, in the direction from the front end of the shoe <NUM> toward the rear end thereof.

As shown in <FIG>, the midsole <NUM> includes a lower midsole <NUM> and an upper midsole <NUM>.

The lower midsole <NUM> is disposed on the outsole <NUM>. Namely, the lower surface of the lower midsole <NUM> is covered with the outsole <NUM>. The lower surface of the lower midsole <NUM> may be covered only partially with the outsole <NUM>, or the entire region of the lower surface thereof may be covered with the outsole <NUM>.

The upper midsole <NUM> is connected onto the lower midsole <NUM>. The upper midsole <NUM> may have a higher compressive elastic modulus than the compressive elastic modulus of the lower midsole <NUM>, or the same compressive elastic modulus as the compressive elastic modulus of the lower midsole <NUM>.

The plate <NUM> forms a part of the sole <NUM>. The plate <NUM> has a higher bending rigidity than the bending rigidity of the midsole <NUM>. The plate <NUM> is made from a fiber-reinforced resin or non-fiber-reinforced resin. Examples of the fiber used for the fiber-reinforced resin include carbon fiber, glass fiber, aramid fiber, Dyneema® fiber, Zylon® fiber, boron fiber, and the like. Examples of the non-fiber-reinforced resin include polymer resins such as polyurethane-based thermoplastic elastomer (TPU) and amide-based thermoplastic elastomer (TPA).

The plate <NUM> is disposed in the midsole <NUM>. As shown in <FIG>, the plate <NUM> is disposed within the midsole <NUM> in the present embodiment. Specifically, the plate <NUM> is disposed between the lower midsole <NUM> and the upper midsole <NUM>. The plate <NUM> is bonded to at least one of the lower midsole <NUM> and the upper midsole <NUM>. The midsole <NUM> has a receptacle defining a space in which the plate <NUM> is received. The receptacle has a shape corresponding to the shape of the plate <NUM>. In the present embodiment, the receptacle is formed in the lower surface of the upper midsole <NUM>.

The plate <NUM> includes a front support portion <NUM>, a center support portion <NUM>, and a rear support portion <NUM>.

The front support portion <NUM> is a part that supports the forefoot portion of a wearer of the shoe <NUM>. The front support portion <NUM> is formed at a position overlapping, in the thickness direction of the sole <NUM>, MP joints of the foot of the wearer. As shown in <FIG>, the front support portion <NUM> is formed to extend over a range from a front end 300a of the plate <NUM> to a position at a first length L1 from a front end 200a of the midsole <NUM> toward a rear end 200b thereof. The first length L1 is a length of <NUM>% of the length from the front end 200a to the rear end 200b of the midsole <NUM>.

<FIG> schematically shows a cross section of the shoe <NUM> in the foot width direction, at a position passing the front support portion <NUM>. The front support portion <NUM> is formed flat as seen in the cross section in the foot width direction as shown in <FIG>, when the sole <NUM> is placed on the flat plane P (see <FIG>). In the present embodiment, the front support portion <NUM> is formed to have a flat cross section in the foot width direction over its entire region. The front support portion <NUM> may be formed in a curved shape with a single downward protrusion in a cross section in the foot width direction, when the sole <NUM> is placed on the flat plane P.

The center support portion <NUM> is a part that supports at least the midfoot portion of the wearer. The center support portion <NUM> has a shape extending rearward from the front support portion <NUM>. Namely, the front support portion <NUM> and the center support portion <NUM> are contiguous to each other in the foot length direction. The center support portion <NUM> is formed at a position that overlaps at least metatarsal bones B10 of the wearer of the shoe <NUM> in the thickness direction of the sole <NUM>. In the present embodiment, the center support portion <NUM> has a shape that extends from the position overlapping, in the thickness direction of the sole <NUM>, the metatarsal bones B10 of the wearer to a position overlapping the cuboid bone B20.

As shown in <FIG>, the center support portion <NUM> is formed to extend over a range from the rear end of the front support portion <NUM> to a position at a second length L2 from the front end 200a of the midsole <NUM> toward the rear end 200b thereof. The second length L2 is a length that is <NUM>% of the length from the front end 200a to the rear end 200b of the midsole <NUM>.

The center support portion <NUM> has a shape with an upward protrusion C1 and a downward protrusion C2 arranged alternately in the foot width direction, in a cross section in the foot width direction as shown in <FIG>, when the sole <NUM> is placed on the flat plane P, where the upward protrusion C1 has a shape curved to protrude upward and the downward protrusion C2 has a shape curved to protrude downward. In <FIG>, "IN" refers to the inner side in the foot width direction, and "OUT" refers to the outer side in the foot width direction. This is applied as well to other drawings.

In the present embodiment, the center support portion <NUM> includes a center projection <NUM>, an inner projection <NUM>, and an outer projection <NUM>.

The center projection <NUM> is formed centrally in the foot width direction. As shown in <FIG>, the center projection <NUM> is located on a heel center HC. The heel center HC refers to a straight line connecting the center of the calcaneus bone B30 of a standard wearer of the shoe <NUM> and a point between the third toe and the fourth toe.

The inner projection <NUM> is formed inward of the center projection <NUM> and contiguously to the center projection <NUM> in the foot width direction. The outer projection <NUM> is formed outward of the center projection <NUM> and contiguously to the center projection <NUM> in the foot width direction.

According to the claimed invention, the center projection <NUM> is formed by the upward protrusion C1 and the inner projection <NUM> and the outer projection <NUM> are each formed by the downward protrusion C2. Instead, but not according to the claimed invention, the center projection <NUM> may be formed by the downward protrusion C2 and the inner projection <NUM> and the outer projection <NUM> may each be formed by the upward protrusion C1. The curvature of the center projection <NUM>, the curvature of the inner projection <NUM>, and the curvature of the outer projection <NUM> may be identical to each other.

As shown in <FIG>, the length from the upper end of the center projection <NUM> (upward protrusion C1) to the lower end of the outer projection <NUM> (downward protrusion C2) is largest in a center portion of the center support portion <NUM> in the foot length direction, and decreases gradually from the center portion toward the front support portion <NUM> or the rear support portion <NUM>. In <FIG>, the lower end of the downward protrusion C2 is indicated by a broken line.

<FIG> is a cross section of the shoe <NUM> along a line segment AB, a line segment BC, a line segment CD, and a line segment DE shown in <FIG>. A point A is a point of intersection of the shoe center SC and the front end of the sole <NUM>. A point B is a point of intersection of a front part of the second metatarsal bone and the shoe center SC. A point C is a point of intersection of a rear part of the fourth metatarsal bone and the heel center HC. A point D is a point of intersection of the heel center HC and a rear end 300b of the plate <NUM>. A point E is a point of intersection of the shoe center SC and the rear end of the sole <NUM>.

As shown in <FIG>, in the state in which the sole <NUM> is placed on the flat plane P, the opposite ends of the center support portion <NUM> in the foot width direction are not parallel with the flat plane P.

The rear support portion <NUM> is a part that supports the rearfoot portion of a wearer of the shoe <NUM>. The rear support portion <NUM> has a shape extending rearward from the center support portion <NUM>. Namely, the center support portion <NUM> and the rear support portion <NUM> are contiguous to each other in the foot length direction. The rear support portion <NUM> is formed at a position that overlaps, in the thickness direction of the sole <NUM>, the calcaneus bone B30 of the wearer, more specifically at a position that overlaps the lowermost point of the calcaneus bone B30. The rear support portion <NUM> is formed to extend over a range from the rear end of the center support portion <NUM> to the rear end 300b of the plate <NUM>. The rear support portion <NUM> is formed such that its cross section in the foot width direction is flat. Note that the rear support portion <NUM> may not be provided.

As shown in <FIG>, the midsole <NUM> supports the plate <NUM> in such a manner that, when the sole <NUM> is placed on the flat plane P, the boundary between the front support portion <NUM> and the center support portion <NUM> is located at the lowermost point of the plate <NUM> and a part of the plate <NUM> that is located rearward of the boundary has a posture separated gradually away from the flat plane P, toward the rear in the longitudinal direction of the shoe <NUM>.

In the plate <NUM> of the present embodiment described above, the center support portion <NUM> has a shape with the upward protrusion C1 and the downward protrusion C2 arranged alternately in the foot width direction, which thereby ensures a sufficient bending rigidity of the center support portion <NUM> in the foot length direction. Therefore, arch falling from the ground contact phase to the take-off phase is suppressed. Further, the front support portion <NUM> and the center support portion <NUM> are contiguous to each other in the foot length direction, which thereby suppresses excessive deformation of the midsole <NUM> in the take-off phase.

In the following, modifications of the above embodiment are described.

As shown in <FIG>, the curvature of the center projection <NUM> may be smaller than the curvature of inner projection <NUM> and the curvature of the outer projection <NUM>. In this case, while the bending rigidity of the center support portion <NUM> in the foot length direction is somewhat decreased relative to the above embodiment, the cushioning effect in the ground contact phase is increased.

As shown in <FIG>, the apex of the center projection <NUM> may be shifted away from the heel center HC toward the lateral foot side. In this case, smooth weight transfer is achieved in the transition from the ground contact phase to the take-off phase.

As shown in <FIG>, the apex of the center projection <NUM> may be shifted away from the heel center HC toward the medial foot side. In this case, the bending rigidity of a part of the center support portion <NUM> that is located inward of the heel center HC is increased, which thereby suppresses occurrence of pronation in the ground contact phase.

As shown in <FIG>, the plate <NUM> may be placed in the front surface of the midsole <NUM> (the front surface of the upper midsole <NUM>). In this case, the midsole <NUM> may have a monolayer structure. In this case, the efficiency of load transmission from the wearer's foot to the plate <NUM> is increased, and therefore, force of the foot is transferred effectively to the ground.

As shown in <FIG>, the plate <NUM> may be placed to be in contact with the back surface of the midsole <NUM> (the back surface of the lower midsole <NUM>). In this case, the midsole <NUM> may have a monolayer structure. In this case, a larger distance from the foot to the plate <NUM> is ensured, and therefore, the midsole <NUM> effectively alleviates the impact applied to the foot in the ground contact phase.

It would be appreciated by those skilled in the art that a plurality of above-described illustrative embodiments are specific examples of the aspects as set forth below.

In this plate, the center support portion has the upward protrusion and the downward protrusion arranged alternately in the foot width direction, which ensures a sufficient bending rigidity of the center support portion in the foot length direction. Thus, arch falling from the ground contact phase to the take-off phase is suppressed. Further, the front support portion and the center support portion are contiguous to each other in the foot length direction, which suppresses excessive deformation of the midsole in the take-off phase.

Preferably, the center support portion has a shape extending to a position overlapping, in the thickness direction of the sole, a cuboid bone of the wearer.

In this way, the above-described advantageous effects are more reliably obtained.

According to the claimed invention, the center support portion includes: a center projection formed centrally in the foot width direction; an inner projection formed inward of the center projection and contiguously to the center projection in the foot width direction; and an outer projection formed outward of the center projection and contiguously to the center projection in the foot width direction.

In this way, the inner projection effectively suppresses arch falling and the outer projection increases the bending rigidity, which thereby effectively supports the load generated by weight transfer from the ground contact phase to the take-off phase.

According to the claimed invention, the center projection is formed by the upward protrusion, and the inner projection and the outer projection are each formed by the downward protrusion.

In this way, an entirely balanced and sufficient bending rigidity in the foot length direction is ensured.

Preferably, a curvature of the center projection, a curvature of the inner projection, and a curvature of the outer projection are identical to each other. In this way, the rigidity of the center support portion in the foot length direction and the cushioning property in the ground contact phase are well-balanced.

A sole according to one aspect of the present disclosure includes: the plate; and a midsole forming a part of the sole. The midsole supports the plate in such a manner that, when the sole is placed on the flat plane, a boundary between the front support portion and the center support portion is located at a lowermost point of the plate and a part of the plate that is located rearward of the boundary has a posture separated gradually away from the flat plane, toward a rear in a longitudinal direction of the shoe.

This sole ensures a sufficient thickness of the part of the midsole that is located downward of the rear end of the plate, which thereby effectively suppresses rearfoot falling from the ground contact phase to the take-off phase.

Claim 1:
A plate (<NUM>) to be used for a sole (<NUM>) forming a part of a shoe (<NUM>), the plate (<NUM>) comprising:
a front support portion (<NUM>) that is formed at a position overlapping, in a thickness direction of the sole, MP joints of a wearer of the shoe, and supports a forefoot portion of the wearer; and
a center support portion (<NUM>) that has a shape extending rearward from the front support portion, is formed at a position overlapping, in the thickness direction of the sole, metatarsal bones (B10) of the wearer of the shoe, and supports at least a midfoot portion of the wearer, wherein
the front support portion (<NUM>) is formed in a flat shape or a curved shape with a single downward protrusion in a cross section in a foot width direction, when the sole is placed on a flat plane, and
the center support portion (<NUM>) has a shape with an upward protrusion (C1) and a downward protrusion (C2) arranged alternately in the foot width direction in a cross section in the foot width direction, when the sole is placed on the flat plane, wherein the upward protrusion has a shape curved to protrude upward and the downward protrusion has a shape curved to protrude downward, wherein
the center support portion (<NUM>) comprises a center projection (<NUM>) formed centrally in the foot width direction by the upward protrusion (C1);
an inner projection (<NUM>) formed inward of the center projection (<NUM>) and contiguously to the center projection (<NUM>) in the foot width direction by the downward protrusion (C2); and
an outer projection (<NUM>) formed outward of the center projection (<NUM>) and contiguously to the center projection (<NUM>) in the foot width direction by the downward protrusion (C2);
characterized in that
an apex of the center projection (<NUM>) is shifted away from the heel center toward the lateral foot side or toward the medial foot side, wherein
a length from an upper end of the center projection (<NUM>) to a lower end of the outer projection (<NUM>) is largest in a center portion of the center support portion (<NUM>) in a foot length direction, and decreases gradually in the midfoot region from the center portion toward the front support portion (<NUM>) or a rear support portion (<NUM>).