WO2019203287A1

WO2019203287A1 - Sole for sports artificial foot

Info

Publication number: WO2019203287A1
Application number: PCT/JP2019/016544
Authority: WO
Inventors: 大太糸井; 耕平佐橋
Original assignee: 株式会社ブリヂストン
Priority date: 2018-04-17
Filing date: 2019-04-17
Publication date: 2019-10-24
Also published as: JP7288897B2; JPWO2019203287A1

Abstract

This sole, for a sports artificial foot that has a leaf-spring shaped foot part extending toward the toe side, is mounted, via at least one bent part, to a ground-contact region extending in an arc shape from the toe to the bent part side. The sole is characterized by having a bottom surface having a shape conforming to the extension shape of the ground-contact region, wherein the bottom surface has at least one width-direction land part demarked by a plurality of width-direction grooves which extend in the width direction of the sole, and both side walls, of the width-direction land part, facing the plurality of width-direction grooves, are formed in a step-like manner toward the ground-contact side from the groove bottom side of the plurality of width-direction grooves.

Description

Prosthetic sole for competition

The present invention relates to a sole to be mounted in a contact area of a prosthetic leg for competition, and more particularly, to a sole for a prosthetic leg for competition that achieves both improvement of anti-slip performance and securing of a ground contact area.

Conventionally, a prosthetic leg for competition (hereinafter also referred to as a prosthetic leg for competition or simply a prosthetic leg) has a leaf spring-like leg part extending to the toe side through the curved part, and the contact area extends in an arc shape from the toe to the curved part side. Is known). Generally, such a prosthetic leg having a leaf spring-like foot portion is provided with a sole that contacts the road surface on the bottom surface of the contact area.

For example, Patent Document 1 exemplifies a sole that is attached to the lower surface of a curved plate spring-like prosthetic leg for competition, such as jogging or running. That is, Patent Document 1 describes a sole in which spikes are attached to the lower surface of a sole that contacts the road surface, and a sole in which a number of outsole portions each having a hexagonal ground surface are provided.

JP 2016-150189 A

However, in the sole exemplified in Patent Document 1, no consideration is given to suppressing slipping of the artificial leg, that is, anti-slip property. For example, when playing a game during rain, etc., it will run on a wet road. At this time, if a water film is present on the road surface, a water film is interposed between the bottom surface of the sole and the road surface, and as a result, the ground contact of the bottom surface of the sole is prevented, thereby causing slip. In particular, on a road surface with a low coefficient of friction μ such as asphalt or stone pavement, a wearer of a prosthetic foot may hesitate to further accelerate. Therefore, in order for a wearer of a prosthetic leg to fully demonstrate the running skill as a competitor, a sole having high anti-slip performance is required.

Also, with the overall speedup of the competition using the prosthetic leg for competition, securing a ground contact area with respect to the road surface is an issue in order to enable stable running.

Therefore, an object of the present invention is to provide a sole for a prosthetic leg for competition that realizes improvement of anti-slip performance and securing of a ground contact area.

The inventor earnestly researched means for solving the above-mentioned problems. That is, when the bottom surface of the sole of the prosthetic leg for competition is examined in detail, a groove is provided on the bottom surface to give an edge component due to unevenness, and a grip force on the road surface is secured through the edge component. It has been conceived that slipping can be prevented. Furthermore, it has been found that the ground contact area with respect to the road surface can be secured by devising the shape of the unevenness, and the present invention has been completed.

The sole of the prosthetic leg for competition of the present invention is a contact of the prosthetic leg having a leaf spring shape extending toward the toe side through at least one curved part and extending in an arc shape from the toe to the curved part side. A sole to be attached to an area, the sole having a bottom surface shaped according to an extending shape of the contact area, and the bottom surface is defined by a plurality of widthwise grooves extending in a width direction of the sole, The width direction land portion has a stepped shape in which both side walls facing the plurality of width direction grooves are directed from the groove bottom side of the plurality of width direction grooves toward the grounding surface side. It is characterized by that.

According to the present invention, it is possible to provide a sole for a prosthetic leg for competition that realizes improved anti-slip performance and secures a ground contact area.

It is a side view of the artificial leg for competition with which the sole concerning one embodiment of the present invention was equipped. It is a figure which shows the pattern of the bottom face of the sole which concerns on one Embodiment of this invention. FIG. 3 is a sectional view taken along line II-II in FIG. 2. It is a figure which shows the variation of the width direction land part. It is a figure which shows the variation of the width direction land part. It is a figure which shows the variation of the width direction land part. It is a figure for demonstrating stepwise the operation | movement of a leg part, and a ground-contacting form in case the artificial leg for competition is worn and a wearer runs straight ahead. It is a figure for demonstrating stepwise the operation | movement of a leg part, and a ground-contacting form in case the artificial leg for competition is worn and a wearer runs straight ahead. It is a figure for demonstrating stepwise the operation | movement of a leg part, and a ground-contacting form in case the artificial leg for competition is worn and a wearer runs straight ahead. It is a figure for demonstrating stepwise the operation | movement of a leg part, and a ground-contacting form in case the artificial leg for competition is worn and a wearer runs straight ahead. It is a figure which shows the pattern of the bottom face of the sole which concerns on other embodiment of this invention.

Hereinafter, the sole of the prosthetic leg of the present invention (hereinafter also referred to as a sole) of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a side view of a prosthetic leg 1 for competition equipped with a sole 5 according to the first embodiment of the present invention. The prosthetic leg 1 for competition has a leaf spring-like leg 2 and a sole 5 is attached to a contact area on the tip side. In addition, although illustration is abbreviate | omitted, the base end part of the foot part 2 is connected to a socket via an adapter, and a wearer wears a prosthetic leg by accommodating the stump of a wearer's leg in a socket. be able to. As the adapter and the socket, those corresponding to the stump position of the foot such as a thigh prosthesis and a crus prosthesis are used. FIG. 1 shows the foot 2 and the sole 5 in an upright state of a wearer who wears the prosthetic leg 1 for competition.

Hereinafter, in this embodiment, in the height direction of the prosthetic leg for competition, the side where the foot 2 is connected to the adapter is referred to as the connection side, and the side where the foot 2 contacts the road surface S is referred to as the ground side. Further, the toe T of the prosthetic leg 1 for competition refers to the foremost point where the foot 2 extends from the connection side and terminates.

In this embodiment, the foot portion 2 of the prosthetic leg 1 for competition has a shape extending in a plate shape toward the toe T via at least one curved portion, in the illustrated example, 1 curved portion 3. In FIG. 1, the foot part 2 includes, in order from the connection side to the ground side, a straight part 2 a, a curved part 2 b that is convex toward the toe T side, a curved part 3 that is convex toward the rear side in the foot front-rear direction Y, The curved portion 2c and the grounding portion 4 extending to the toe T side in an arc shape protruding to the grounding side.

Note that the material of the foot 2 is not limited, but it is preferable to use carbon fiber reinforced plastic or the like from the viewpoint of strength and weight reduction.

The grounding portion 4 has, on the grounding side, a contact area 4s extending in an arc shape from the toe T toward the bending portion 3, and a sole 5 is attached to the contact area 4s. The contact area 4s refers to the entire area that comes into contact with the road surface S when the wearer who wears the prosthetic leg 1 performs a straight traveling operation. In the state where the sole 5 is attached, the contact area 4s is the sole 5 It contacts with the road surface S via.

The material of the sole 5 is not particularly limited. For example, rubber or the like can be used.

The sole 5 has a shape according to the extended shape of the contact area 4s. The grounding side of the sole 5 is a sole bottom surface 5s. As shown in FIG. 1, the sole bottom surface 5s has a shape in which the arcs X1 and X2 are continuous from the toe T side to the bending portion 3 side. In the present embodiment, the arc X1 and the arc X2 have different radii of curvature, but may have the same radius of curvature.

Hereinafter, the direction in which the sole bottom surface 5s extends from the toe T side to the curved portion 3 side is referred to as the Y direction, and the width direction of the sole bottom surface 5s orthogonal to the Y direction is referred to as the W direction. Furthermore, the thickness direction of the sole 5 is referred to as the Z direction.

FIG. 2 is a diagram showing a pattern of the sole bottom surface 5s according to the embodiment of the present invention. In the illustrated example, at least one width direction land portion 10, in the illustrated example, three rows in the width direction land portion 10, which are partitioned by a plurality of width direction grooves 20 extending in the W direction, is disposed on the sole bottom surface 5 s.

3A is a cross-sectional view orthogonal to the extending direction of the width-direction land portion 10, that is, a cross-sectional view taken along the line II-II in FIG. As shown in the drawing, the width direction land portion 10 has two steps on both side walls 10Wa and 10Wb facing the plurality of width direction grooves 20 from the groove bottom 20b side of the plurality of width direction grooves 20 toward the grounding surface 10s side. Is. In the illustrated example, the side wall 10Wa has a side wall portion Sa1 extending in the Z direction and a side wall portion Ca1 extending in the Y direction, which constitute the first step P1 from the groove bottom 20b side, and further, from the side wall portion Ca1 to the ground plane. It has a side wall portion Sa2 extending in the Z direction toward 10s. Further, the side wall 10Wb has a side wall portion Sb1 extending in the Z direction and Cb1 extending in the Y direction, which constitute the first step P1 from the groove bottom 20b side, and further, from the side wall portion Cb1 toward the ground plane 10s. It has a side wall portion Sb2 extending in the Z direction. In the present embodiment, the step formed by the side wall portions Sa2 and Sb2 and the ground plane 10s is referred to as a second step P2.

By making the side walls 10Wa and 10Wb stepped, a high edge function is given to the sole bottom surface 5s, and when the wearer of the prosthetic leg 1 for competition travels straight on the width direction land portion 10, a grip to the road surface S Power can be exerted and anti-slip performance can be improved. Further, when the road surface S side, that is, the second stage P2 is first grounded and compressed on the road surface S, the water interposed between the first stage P1 and the road surface S is pushed out to the road surface S side. Since water can be efficiently discharged, drainage performance is improved and higher slip resistance can be obtained. Further, by compressing the second stage P2, the side wall portions Ca and Cb1 of the first stage P1 can also be grounded to the road surface S, so that a ground contact area can be secured.

The side walls 10 </ b> Wa and 10 </ b> Wb may have any number of steps as long as they are stepped. However, according to the configuration having two steps, the drainage performance can be improved while maintaining the high rigidity of the widthwise land portion 10. it can.

In the present embodiment, the height h1 in the Z direction of the width direction land portion 10 and the maximum length w1 in the direction orthogonal to the extending direction of the width direction land portion 10 are such that the height h1 is the length w1. Is preferably 1.5 times or more and 10.0 times or less. According to this structure, when the wearer of the prosthetic leg 1 for running travels, sufficient rigidity can be imparted to the widthwise land portion 10 while providing the sole bottom surface 5s with appropriate flexibility.

Further, the maximum length w1 orthogonal to the extending direction of the widthwise land portion 10 and the length w2 of the ground surface 10s of the widthwise land portion orthogonal to the extending direction of the widthwise land portion 10 are as follows: It is preferable that the relationship of Formula (1) is satisfied.
(Formula (1)) 0.3 ≦ (w1-w2) /w1≦0.9
By making the relationship (w1-w2) / w1 between the maximum length w1 of the land portion 10 in the width direction and the length w2 of the ground contact surface 10s to be 0.3 or more, the drainage performance by the stepped side wall is more effective. By making it 0.9 or less, a sufficient ground contact area at the moment of the first ground contact of the width direction land portion 10 can be secured, and the anti-slip performance can be improved.

In addition, it is preferable that the maximum length w1 orthogonal to the extending direction of the width direction land portion 10 is 2.0 mm or more and 8.0 mm or less. By setting it as 2.0 mm or more, sufficient land part rigidity is provided to the width direction land part 10, and by setting it as 8.0 mm or less, the flexibility of the sole bottom face 5s in the Y direction can be maintained. Preferably, the length w1 is not less than 3.0 mm and not more than 6.5 mm, and more preferably not less than 3.8 mm and not more than 4.5 mm.

Moreover, it is preferable that the length w2 orthogonal to the extending direction of the width direction land portion 10 of the ground surface 10s of the width direction land portion is 0.5 mm or more and 2.5 mm or less. By setting it to 0.5 mm or more, a sufficient ground contact area at the moment of the first ground contact of the width direction land portion 10 can be ensured, and the anti-slip performance can be enhanced. Furthermore, the drainage performance by the stepped side wall can be more effectively exhibited by setting it to 2.5 mm or less.

Moreover, the maximum height h1 in the Z direction of the width direction land portion 10 and the maximum height h2 of the step P2 including the ground contact surface 10s of the width direction land portion 10 satisfy the relationship of the following formula (2). Is preferred.
(Expression (2)) 0.25 ≦ h2 / h1 ≦ 0.67
The height of the step P2 including the ground contact surface 10s that first comes into contact with the road surface S is set to 0.25 times or more the maximum height h1 of the widthwise land portion 10, so that the drainage performance by the stepped side wall is achieved. When the wearer of the athletic prosthesis 1 runs, the width-direction land portion 10 is provided with appropriate flexibility on the sole bottom surface 5s. Can be provided with sufficient rigidity.

In addition, it is preferable that the maximum height h1 in the Z direction of the width direction land portion 10 is 1.0 mm or more and 7.0 mm or less. By setting the thickness to 1.0 mm or more, the drainage performance can be sufficiently secured. By setting the thickness to 7.0 mm or less, the flexibility and rigidity of the sole bottom surface 5s can be improved when the wearer of the prosthetic leg 1 for competition runs. It can be compatible. More preferably, they are 2.0 mm or more and 3.5 mm or less, More preferably, they are 2.4 mm or more and 3.5 mm or less.

In addition, it is preferable that the maximum height h2 in the Z direction of the step P2 including the width direction land portion 10 grounding surface 10s is 0.5 mm or more and 2.5 mm or less. By setting it to 0.5 mm or more, drainage performance due to the stepped side wall can be more effectively exhibited, and by setting it to 2.5 mm or less, the sole bottom surface 5 s can be used when the wearer of the prosthetic leg 1 for competition runs. It is possible to impart sufficient rigidity to the widthwise land portion 10 while providing appropriate flexibility. More preferably, the maximum height h2 is not less than 0.7 mm and not more than 1.5 mm, and more preferably not less than 1.2 mm and not more than 1.5 mm.

The variation of the shape of the width direction land part 10 is shown below.
Figure 3B shows the width direction land portion 10 and both side walls 10Wa ₂ and 10Wb ₂ to 3-step staircase-like. In the illustrated example, the side wall 10Wa ₂ constitutes a stage P1 of the first stage from the groove bottom 20b side, has a sidewall portion Ca1 extending sidewall portion Sa1 and Y directions extending in the Z-direction, the stage P2 of the second stage A side wall portion Sa2 extending in the Z direction from the side wall portion Ca1 toward the ground surface 10s side and a side wall portion Ca2 extending in the Y direction, and further extending in the Z direction from the side wall portion Ca2 toward the ground surface 10s A portion Sa3 is included. Further, the side wall 10Wb ₂ constitutes a stage P1 of the first stage from the groove bottom 20b side, has a sidewall portion Cb1 extending sidewall portions Sb1 and Y directions extending in the Z-direction, constitutes the stage P2 of the second stage The side wall portion Sb2 extends in the Z direction from the side wall portion Cb1 toward the ground surface 10s, and the side wall portion Cb2 extends in the Y direction. Further, the side wall portion Sb3 extends in the Z direction from the side wall portion Cb2 toward the ground surface 10s. have. In the example illustrated in FIG. 3B, the stage formed by the side wall portions Sa3 and Sb3 and the ground plane 10s is referred to as a third stage P2. According to the said structure, the edge component which goes to a Y direction can be increased, and higher drainage performance can be obtained. Further, when the width direction land portion 10 is grounded, the step P3 and the step P2 are sequentially compressed in order from the ground surface 10s side, and a sufficient ground contact area can be secured.

Figure 3C shows a widthwise land portion 10 having side walls 10Wa ₃ and 10Wb _3. The step on the most groove bottom 20b side of the width direction land portion 10 has a shape in which the length orthogonal to the extending direction of the width direction land portion 10 gradually increases from the ground contact surface 10s side to the groove bottom 20b side. Yes. That is, as shown in the example, the step P1 on the most groove bottom side of the width direction land portion 10 has a width w3 on the groove bottom 20b side from a length w3 orthogonal to the extending direction of the width direction land portion 10 on the ground surface 10s side. The length orthogonal to the extending direction of the width direction land portion 10 gradually increases until reaching the maximum length w1 orthogonal to the extending direction of the direction land portion 10. When the width direction land portion 10 is grounded, the step P2 is compressed from the grounding surface 10s side, but the length of the step P1 is gradually increased toward the groove bottom 20b side to resist the compression of the step P1. The rigidity is increased, and the ground contact area can be efficiently secured.

In the illustrated example, the Y-direction distance w4 from the boundary e1 between the width direction land portion 10 and the groove bottom 20b on the toe T side to the side wall portion Ca1 of the step P1, and the width direction land portion on the bending portion 3 side. The Y-direction distance w5 from the boundary e2 between the groove 10 and the groove bottom 20b to the side wall portion Cb1 of the step P1 is the same length, but may be a different length. For example, when the Y-direction distance w4 is longer than the Y-direction distance w5, the inclination to the groove bottom 20b of the step P1 becomes gentler on the curved portion 3 side than on the toe T side. Then, when the contact portion of the sole bottom surface 5s with respect to the road surface S changes from the curved portion 3 side to the toe T side, uneven wear of the width direction land portion 10 can be suppressed.

The Y-direction distance w4 and the Y-direction distance w5 vary depending on the wearer of the prosthetic leg 1 for competition, the competition event, and the like, but are preferably 0.5 mm or more and 2.5 mm or less, respectively. By setting it as 0.5 mm or more, the rigidity of the width direction land part 10 can be secured while improving drainage performance, and by setting it as 2.5 mm or less, drainage while ensuring the ground contact area with the road surface S. The performance can be fully exhibited. Preferably, it is 0.5 mm or more and 1.5 mm or less, More preferably, it is 0.5 mm or more and 1.0 mm or less.

Further, in FIG. 3D, side wall portions Sa2 extending in the Z-direction from the side wall portions Ca1 sidewall 10Wa ₄ toward the ground surface 10s has a circular arc r1 that has a radius of curvature of the center to the outside in the width direction land portion 10, the side walls A side wall portion Sb2 extending in the Z direction from the 10 Wb ₄ side wall portion Cb1 toward the ground contact surface 10s has an arc r2 having a center of curvature radius outside the width direction land portion 10. By making the side wall portions Sa2 and Sb2 include arcs, the rigidity of the width direction land portion 10 can be increased.

Next, with reference to FIG. 4A, 4B, 4C, 4D and FIG. 2, the suitable arrangement | positioning and number of the width direction land parts 10 are demonstrated.

FIGS. 4A, 4B, 4C, and 4D are diagrams for explaining step by step the operation of the foot portion 2 and the ground contact surface 5s when the wearer who wears the prosthetic leg 1 for competition travels straight ahead. It is. The upper part of each drawing is a side view of the foot 2 and the sole 5, and the lower part of each drawing is a grounding form of the sole bottom surface 5s when the wearer wearing the competition artificial leg 1 performs a straight running operation. It shows the transition.

FIG. 4A shows a state in which the competition prosthetic leg 1 lifted by the wearer is lowered onto the road surface S, and the total weight is loaded on the competition prosthetic leg 1. As shown in the lower part of the drawing, when the prosthetic leg 1 is lowered onto the road surface S, the contact area of the sole bottom surface 5s is in the vicinity of the center of the bottom surface. It is a region that is spaced in the direction.

FIG. 4B shows a state in which the wearer steps forward from the state of FIG. 4A while the full weight is loaded on the prosthetic leg 1 for competition. In the case of a healthy person's running, it is common to step on the ground in order from the heel side to the toe side of the shoe sole to be grounded first, but the prosthetic leg for competition 1 is more curved than where it was grounded first. The grounding area has moved to the part 3 side.

FIG. 4C shows a state in which the wearer swings forward the opposite leg to the side on which the athletic prosthetic leg 1 is worn and starts to kick out the athletic prosthetic leg 1. When this kick-out operation is started, the game prosthetic leg 1 is grounded in the region on the toe T side of the sole bottom surface 5s from the region shown in FIGS. 4A and 4B.

FIG. 4D shows a state immediately before leaving the road surface S at the final stage where the wearer kicks out the prosthetic leg 1 for competition. In order to kick out from the toe T on the bottom surface 5s of the sole, the grounding is made in the region closer to the toe T than FIG. 4C.

In this embodiment, as shown in FIG. 2, the width direction land portion 10 is arranged in a region corresponding to the ground contact region shown in FIG. 4A. That is, the competition prosthetic leg 1 lifted by the wearer is lowered onto the road surface S, and the overall weight is loaded on the competition prosthetic leg 1. Here, it is important that the region is sufficiently gripped with the road surface S so that the balance of the entire body is maintained even when the wearer applies the total weight to the prosthetic leg 1 for competition. The land portion 10 in the width direction is disposed in such a region to provide a high edge function due to the stepped side wall, to ensure a sufficient grip force on the road surface S, to give the region a high anti-slip performance, Can be secured.

In FIG. 2 described above, by arranging three rows in the width direction land portion 10 in the ground contact area shown in FIG. 4A, it is possible to improve the anti-slip performance of the sole bottom surface 5s and to ensure the ground contact area.

Next, with reference to FIG. 4A, 4B, 4C, 4D and FIG. 5 described above, the groove pattern of the bottom surface 5s of the sole of the prosthetic leg for competition according to another embodiment will be described. The sole of the prosthetic leg for competition according to the second embodiment has the same basic configuration as that of the first embodiment, and is formed with a width direction land portion having a chamfered portion. The shape of the land in the width direction is different.

The pattern of the sole bottom surface 5s of the prosthetic leg sole for competition according to the second embodiment is based on the knowledge about the transition of the ground contact form of the sole bottom surface 5s described above.

5, the sole bottom surface 5s includes width

direction land portions

100, 110, 120, and 140 that extend in the width direction W defined by the width direction groove 200, and a sipe 130.

The width direction land portion 100 includes a width direction extending portion 100a extending substantially zigzag in the W direction, a toe side protruding portion 100b extending to the toe T side from a bent portion that is bent in a convex direction toward the toe T side, and a curved shape. It is a shape including a bent portion side protruding portion 10c extending from the bent portion bent in the direction to be convex toward the portion 3 side to the bent portion 3 side. The width direction land portion 110 has a shape including a width direction extending portion 110a, a toe side protruding portion 110b, and a curved portion side protruding portion 110c. The width direction land portion 140 has the same shape as the width direction land portion 110.

Here, in the region where the width

direction land portions

100 and 110 are arranged, the wearer first lands on the ground contact region shown in FIG. 4A and FIG. 4B described above, and the entire weight is loaded on the prosthetic leg 1 for competition. This is the area where the stepping action is performed in the Therefore, it is important that the region is sufficiently gripped with the road surface S so that the balance of the entire body is maintained even if the wearer applies the total weight to the prosthetic leg 1 for competition. By forming the width direction extending portion 100a in a zigzag shape and further forming the toe side protruding portion 100b and the curved portion side protruding portion 100c, the drainage function is effectively exhibited along the Y direction, and the road surface S It is possible to secure a sufficient grip force and to prevent the artificial leg from slipping, that is, to improve the anti-slip performance.

Note that the width-direction land portion 110 has a land portion width larger than that of the width-direction land portion 100. As shown in FIG. 4B, in the state where the vehicle is stepped on immediately after landing, the ground contact area changes to the curved portion 3 side, that is, the direction opposite to the direction in which the wearer proceeds, from the first grounded area. Here, the movement of the upper body that the wearer tries to move forward and the direction of transition of the ground contact area are temporarily reversed, and the second half kick-out operation of the ground contact form shown in FIGS. 4C to 4D This is a stage where high driving force is required. By placing the width direction land portion 110 having a width larger than the width direction land portion 100 on the curved portion 3 side with respect to the width direction land portion 100 and increasing the land portion ratio, the rigidity of the arrangement region is increased and the stepping operation is performed. Realizes high propulsive force for smoothly connecting the kicker to the kicking motion.

The width direction land portion 120 extends in a substantially zigzag shape in the W direction, and the width of the land portion is a repetition of wide and narrow, from a width direction extension portion 120a, and a bent portion that bends in a direction that protrudes toward the toe T side. The extension of the width direction extending portion 120a from the toe side protruding portion 120b extending so as to be convex in the extending direction of the width direction extending portion 120a and the bent portion bending in the protruding direction on the bending portion 3 side. It is a shape including the curved part side protrusion part 120c extended so that it may become convex in the existing direction.

The region where the width direction land portion 120 is disposed is a region that is grounded when the kicking-out operation of the prosthetic leg 1 for competition shown in FIG. 4C is started. By adopting a shape in which the land portion width changes, drainage performance can be improved while increasing the land portion rigidity. In other words, it is possible to avoid slipperiness caused by increasing the land portion width while increasing the land portion width by adopting a shape in which a portion having a relatively large land portion width and a small portion coexist. it can.

Further, the sole bottom surface 5s of the present embodiment includes a plurality of sipes 130 extending linearly in a direction inclined with respect to the W direction in a region from the end edge on the toe T side toward the curved portion 3 side. Is preferred. In the region where the sipe 130 is arranged, as shown in FIG. 4D, the wearer swings forward the foot opposite to the side on which the game prosthetic leg 1 is worn, and performs the kick-out operation of the game prosthetic leg 1. It is an area. This region is a region where wear tends to progress particularly because the region is grounded in order toward the toe T and the wearer touches and slides the road surface S on the sole bottom surface 5s. Therefore, in this region, it is important to improve the wear resistance and maintain the resistance to slipping during ground contact.

In particular, the constant region from the edge of the sole bottom surface 5s on the toe T side where the sipe 130 is formed is a region corresponding to the arc X1 continuous from the toe T with a constant radius of curvature in FIG. As shown in 4D, when the wearer who wears the prosthetic leg 1 for competition performs a kicking-out operation, the wearer tends to come into contact with the ground at the end to cause more severe wear. Therefore, in this region, it is necessary to provide particularly high wear resistance. Therefore, the sipe 130 having a width smaller than that of the groove formed in another region is formed, and the edge component is distributed without impairing the rigidity. Therefore, the sole bottom surface 5s can be protected from intense wear, and the service life of the foot 2 itself can be extended.

In any of the embodiments, in the pattern of the sole bottom surface 5s, it is preferable that fluorine is applied to the groove wall and the groove bottom that define the width direction groove that defines the width direction land portion. By applying fluorine to the groove wall and the groove bottom of the width direction groove, the drainage performance on the sole bottom surface 5s can be enhanced.

1: prosthetic leg for competition, 2: foot, 2a: straight part, 2b, 2c: curved part, 3: curved part, 4: grounding part, 4s: contact area, 5: sole, 5s: sole bottom, 10: width direction land _{portion, 10Wa, 10Wb, 10Wa 2,} 10Wb 2, 10Wa 3, 10Wb 3, 10Wa 4, 10Wb 4: side wall, 20: widthwise grooves, 20b: groove bottom, e1, e2: boundary, P1, P2, P3 : Step, Sa1, Sa2, Sa3, Ca1, Ca2, Sb1, Sb2, Sb3, Cb1, Cb2: Side wall portions, 100, 110, 120, 140: Land in the width direction, 130: Sipe, 100a, 110a, 120a: Width Direction extending portion, 100b, 110b, 120b: toe side protruding portion, 100c, 110c, 120c: bending portion side protruding portion, Y: direction in which sole bottom surface 5s extends from toe T side to bending portion 3 side , W: width direction of the sole bottom 5s orthogonal to the Y direction, Z: the thickness direction of the sole 5

Claims

A sole to be attached to a contact area extending in an arc shape from the toe to the curved portion side of the prosthetic leg for competition having a leaf spring-like foot portion extending to the toe side through at least one curved portion,
The sole has a bottom surface shaped according to the extending shape of the contact area,
The bottom surface has at least one width direction land portion defined by a plurality of width direction grooves extending in the width direction of the sole,
The prosthetic leg for a competition, wherein the side walls facing the plurality of widthwise grooves are stepped from the groove bottom side to the grounding surface side of the plurality of width direction grooves. Sole.
2. The sole of the prosthetic leg for competition according to claim 1, wherein both side walls facing the plurality of widthwise grooves have a two-step shape from the plurality of widthwise grooves toward the ground surface.
The maximum length w1 orthogonal to the extending direction of the widthwise land portion and the length w2 of the ground contact surface of the widthwise land portion orthogonal to the extending direction of the widthwise land portion are as follows: The sole of the prosthetic leg for competition according to claim 1 or 2, satisfying the relationship (1).
(Formula (1)) 0.3 ≦ (w1-w2) /w1≦0.9
The maximum height h1 in the thickness direction of the sole of the width direction land portion and the maximum height h2 of the step including the ground contact surface of the width direction land portion satisfy the relationship of the following expression (2). The sole of the prosthetic leg for competition according to any one of claims 1 to 3.
(Expression (2)) 0.25 ≦ h2 / h1 ≦ 0.67
The step on the most groove bottom side of the width direction land portion has a shape in which a length perpendicular to the extending direction of the width direction land portion gradually increases from the grounding surface side toward the groove bottom side. The sole of the prosthetic leg for competition according to any one of 1 to 4.