SOLE OF ATHLETIC PROSTHETIC LEG
20210290414 · 2021-09-23
Assignee
Inventors
Cpc classification
International classification
Abstract
A sole which is attached to a ground contact region of an athletic prosthetic leg having a leaf-spring-like leg portion extending to a side of a toe via at least one curved portion, the ground contact region extending in an arc from the toe to a side of the curved portion is provided. The sole includes a bottom surface having a shape conforming to an extending shape of the ground contact region, and the bottom surface has at least one width direction land portion defined by a plurality of width direction grooves extending in a width direction of the sole. Moreover, the width direction land portion includes a chamfer at each of both end edges at border positions, respectively, between a contact patch and both side walls facing the plurality of width direction grooves.
Claims
1. A sole of an athletic prosthetic leg, the sole being configured to be attached to a ground contact region of the athletic prosthetic leg having a leaf-spring-like leg portion extending to a side of a toe via at least one curved portion, the ground contact region extending in an arc from the toe to a side of the curved portion, the sole comprising: a bottom surface having a shape conforming to an extending shape of the ground contact region, wherein the bottom surface has at least one width direction land portion defined by a plurality of width direction grooves extending in a width direction of the sole, and the width direction land portion includes a chamfer at each of both end edges at border positions, respectively, between a contact patch and both side walls facing the plurality of width direction grooves.
2. The sole of the athletic prosthetic leg according to claim 1, wherein a height of the chamfer in a thickness direction of the sole is 25% or more and 67% or less of a height of the width direction land portion in the thickness direction of the sole.
3. The sole of the athletic prosthetic leg according to claim 1, wherein a total of a length w2 and a length w3 of the chamfers at both the end edges in a direction orthogonal to an extending direction of the width direction land portion and a length w1 of the width direction land portion in a direction orthogonal to the extending direction of the width direction land portion satisfy a relationship of the following formula:
0.3≤[w1−(w2+w3)]/w1≤0.9. (Formula)
4. The sole of the athletic prosthetic leg according to claim 1, wherein the bottom surface includes at least one sipe extending linearly in a portion which continues with a constant radius of curvature from the toe, and the sipe terminates in the bottom surface and includes a chamfer at each of both the end edges at border positions, respectively, between the bottom surface and both the side walls defining the sipe, both the side walls extending in a longitudinal direction of the sipe.
5. The sole of the athletic prosthetic leg according to claim 2, wherein a total of a length w2 and a length w3 of the chamfers at both the end edges in a direction orthogonal to an extending direction of the width direction land portion and a length w1 of the width direction land portion in a direction orthogonal to the extending direction of the width direction land portion satisfy a relationship of the following formula:
0.3≤[w1−(w2+w3)]/w1≤0.9. (Formula)
6. The sole of the athletic prosthetic leg according to claim 2, wherein the bottom surface includes at least one sipe extending linearly in a portion which continues with a constant radius of curvature from the toe, and the sipe terminates in the bottom surface and includes a chamfer at each of both the end edges at border positions, respectively, between the bottom surface and both the side walls defining the sipe, both the side walls extending in a longitudinal direction of the sipe.
7. The sole of the athletic prosthetic leg according to claim 3, wherein the bottom surface includes at least one sipe extending linearly in a portion which continues with a constant radius of curvature from the toe, and the sipe terminates in the bottom surface and includes a chamfer at each of both the end edges at border positions, respectively, between the bottom surface and both the side walls defining the sipe, both the side walls extending in a longitudinal direction of the sipe.
8. The sole of the athletic prosthetic leg according to claim 5, wherein the bottom surface includes at least one sipe extending linearly in a portion which continues with a constant radius of curvature from the toe, and the sipe terminates in the bottom surface and includes a chamfer at each of both the end edges at border positions, respectively, between the bottom surface and both the side walls defining the sipe, both the side walls extending in a longitudinal direction of the sipe.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] In the accompanying drawings:
[0011]
[0012]
[0013]
[0014]
[0015]
[0016]
[0017]
[0018]
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[0020]
[0021]
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[0023]
DETAILED DESCRIPTION
[0024] Hereinafter, with reference to the drawings, a sole of an athletic prosthetic leg according to the present disclosure (hereinafter, it is also referred to as a sole) will be explained in detail with illustration of embodiments thereof.
[0025]
[0026] Hereinafter, in this embodiment, in a height direction of the athletic prosthetic leg, a side where the leg portion 2 is connected to the adapter is referred to as a connection side, and a side where the leg portion 2 contacts a road surface S is referred to as a ground contact side. Also, a toe T of the athletic prosthetic leg 1 refers to a point at the forefront as a termination of the leg portion 2 extending from the connection side.
[0027] In this embodiment, the leg portion 2 of the athletic prosthetic leg 1 has a plate-like extending shape to the side of the toe T via at least one curved portion, in the illustrated example, one curved portion 3. In
[0028] Additionally, although the material of the leg portion 2 is not limited, from a viewpoint of strength and weight saving, fiber reinforced plastic etc. is preferably used.
[0029] The ground contact portion 4 includes a ground contact region 4s extending from the toe T to the side of the curved portion 3 in an arc at the ground contact side, and the sole 5 is attached to the ground contact region 4s. The ground contact region 4s refers to the entire region abutting the road surface S when the wearer who wears the athletic prosthetic leg 1 executes straight running movement, and in a state that the sole 5 is attached, the ground contact region 4s abuts the road surface S via the sole 5.
[0030] Although the material of the sole 5 is not limited, for example, rubber can be used.
[0031] The sole 5 has a shape conforming to an extending shape of the ground contact region 4s. Also, the ground contact side of the sole 5 is a sole bottom surface 5s. As illustrated in
[0032] Hereinafter, a direction in which the sole bottom surface 5s extends from the side of the toe T to the side of the curved portion 3 is referred to as a Y direction, and a widthwise direction of the sole bottom surface 5s orthogonal to the Y direction is referred to as a W direction. Further, a thickness direction of the sole 5 is referred to as a Z direction.
[0033]
[0034]
[0035] The width direction land portion 10 has the shape including the chamfers c1 and c2, whereby the following effects can be obtained. In other words, during running of the wearer of the prosthetic leg, at the time of movement in which the sole bottom surface 5s sequentially contacts the ground from the side of the curved portion 3 to the side of the toe T, or from the side of the toe T to the side of the curved portion 3, a ground contact pressure has been inclined to be higher at an end edge on the side of the road surface S of the width direction land portion 10. Especially, when the end edge includes an edge component, prior abrasion has been inclined to occur mainly at the edge component. Accordingly, by making a chamfered shape at both the end edges at the border positions between the contact patch 10s and both the side walls 10Wa and 10Wb facing the width direction grooves 20, occurrence of prior abrasion at both the end edges can be avoided. Also, since the width direction land portion 10 contacts the ground from the contact patch 10s and a portion including the chamfers c1 and c2 are pressed in the Z direction, occurrence of strain at the contact patch 10s due to a rubber flow to an outer side in the Y direction can be prevented. Consequently, ground contact pressure can be maintained as even and the footprint area can be fully ensured.
[0036] In the width direction land portion 10, a height h1 in the Z direction and a length w1 in a direction orthogonal to the extending direction of the width direction land portion 10 are preferably such that the height h1 is 1.5 times larger or more and 10.0 times larger or less with respect to the length w1. With this configuration, at the time of running of the wearer of the athletic prosthetic leg 1, a sufficient rigidity can be applied to the width direction land portion 10 allowing the sole bottom surface 5s to have an appropriate flexibility.
[0037] In the chamfers c1 and c2, a height h2 in the Z direction is preferably 25% or more and 67% or less of the height h1 in the Z direction of the width direction land portion 10. Rendering the height h2/the height h1 25% or more can effectively prevent occurrence of uneven wear, while rendering the height h2/the height h1 67% or less can apply the sufficient rigidity to the width direction land portion 10. Preferably, the height h2/the height h1 is 33% or more and 60% or less, and more preferably, 50%.
[0038] Further, in the width direction land portion 10, the length w1 in the direction orthogonal to the extending direction of the width direction land portion 10 and a total of the lengths w2 and w3 of the chamfers c1 and c2 at both the end edges in the direction orthogonal to the extending direction of the width direction land portion 10 preferably satisfy the relationship of the following formula:
0.3≤[w1−(w2+w3)]/w1≤0.9. (Formula)
[0039] By rendering a value of [w1−(w2+w3)]/w1 0.3 times larger or more, the footprint area at a moment of the first ground contact of the width direction land portion 10 can be fully ensured, which improves anti-slip performance. On the other hand, by rendering this value 0.9 times larger or less, drainage performance by the stepwise side walls can be exerted more efficiently.
[0040] More preferably, 0.3≤[w1−(w2+w3)]/w1≤0.8, and more preferably, 0.47≤[w1−(w2+w3)]/w1≤0.78.
[0041] Additionally, while the lengths w2 and w3 have the same length in
[0042] Also, in the chamfers c1 and c2, the lengths w2 and w3 in the direction orthogonal to the extending direction of the width direction land portion 10 preferably have a length of 0.5 times larger or more and 8.0 times larger or less with respect to the height h2. With this configuration, by forming the chamfers c1 and c2, rigidity of the width direction land portion 10 is not deteriorated, and also the footprint area to the road surface can be efficiently ensured while occurrence of uneven wear can be inhibited.
[0043] Additionally, the length w1 of the width direction land portion 10 is preferably 2.0 mm or more and 8.0 mm or less. The length w1 of 2.0 mm or more applies sufficient land portion rigidity to the width direction land portion 10, while the length w1 of 8.0 mm or less can maintain flexibility of the sole bottom surface 5s in the Y direction. Preferably, the length w1 is 3.0 mm or more and 6.5 mm or less, and more preferably, 3.8 mm or more and 4.5 mm or less.
[0044] Also, the lengths w2 and w3 of the chamfers c1 and c2 are preferably 0.5 mm or more and 2.5 mm or less. The lengths w2 and w3 of 0.5 mm or more can improve an inhibition effect of uneven wear, while the lengths w2 and w3 of 2.5 mm or less fully ensure the footprint area without deteriorating rigidity of the width direction land portion 10.
[0045] Further, the height h1 of the width direction land portion 10 is preferably 1.0 mm or more and 7.0 mm or less. The height h1 of 1.0 mm or more can improve drainage performance due to the recesses and protrusions of the sole bottom surface 5s, while the height h1 of 7.0 mm or less can maintain rigidity of the width direction land portion 10. Preferably, the height h1 is 2.0 mm or more and 3.5 mm or less, and more preferably, 2.4 mm or more and 3.5 mm or less.
[0046] The height h2 of the chamfers c1 and c2 are preferably 0.5 mm or more and 2.5 mm or less. The height h2 of 0.5 mm or more can more effectively inhibit occurrence of uneven wear, while the height h2 of 2.5 mm or less can inhibit deterioration of rigidity of the width direction land portion 10. Preferably, the height h2 is 0.7 mm or more and 1.5 mm or less, and more preferably, 1.2 mm or more and 1.5 mm or less.
[0047] Next, with reference to
[0048] The pattern of the sole bottom surface 5s of the sole of an athletic prosthetic leg according to the second embodiment is based on a finding related to a ground contact form obtained from an experiment which will be explained later. An experiment result of the ground contact form of the sole bottom surface 5s will be explained using
[0049]
[0050]
[0051]
[0052]
[0053] Based on the experiment result illustrated in
[0054] In other words, in
[0055] The width direction land portion 100 is shaped to include a width direction extending portion 100a extending in the W direction to be substantially zigzag-shaped, a toe side protruding portion 100b extending to the side of the toe T from a bent portion bending to be convex to the side of the toe T and a curved portion side protruding portion 100c extending to the side of the curved portion 3 from a bent portion bending to be convex to the side of the curved portion 3. The width direction land portion 110 is shaped to include a width direction extending portion 110a, a toe side protruding portion 110b and a curved portion side protruding portion 110c. Additionally, the width direction land portion 140 has the same shape as the width direction land portion 110.
[0056] Here, a region where the width direction land portions 100 and 110 are arranged is one corresponding to the ground contact region illustrated in
[0057] Additionally, a land portion width of the width direction land portion 110 is larger than that of the width direction land portion 100. As illustrated in
[0058] The width direction land portion 120 is shaped to include a width direction extending portion 120a which extends in the W direction to be substantially zigzag-shaped and in which a land portion width is repeatedly wide and narrow, a toe side protruding portion 120b extending to be convex in an extending direction of the width direction extending portion 120a from a bent portion bending to be convex at the side of the toe T and a curved portion side protruding portion 120c extending to be convex in the extending direction of the width direction land portion 120a from a bent portion bending to be convex at the side of the curved portion 3.
[0059] A region where the width direction land portion 120 is arranged is one illustrated in
[0060] Also, the sole bottom surface 5s of this embodiment preferably includes a plurality of sipes 130A each extending linearly in a direction which is inclined to the W direction at a region from an end edge at the side of the toe T toward the side of the curved portion 3. The region where the sipes 130A are arranged is one illustrated in
[0061] Especially, a certain degree of region from the end edge of the sole bottom surface 5s at the side of the toe T where the sipes 130A are formed is a region corresponding to the arc X1 which continues with a certain radius of curvature from the toe T. As illustrated in
[0062] Also, preferably, the sipes 130A terminate in the sole bottom surface 5s, and as illustrated in
[0063] Additionally, the shape of the sipes is arbitrary, and in addition to the shape of the sipe 130A illustrated in
[0064] Additionally, in any of the embodiments described above, in the pattern of the sole bottom surface 5s, fluorine is preferably applied to a groove wall and a groove bottom constituting the width direction groove which defines width direction land portions. Since the fluorine is applied to the groove wall and the groove bottom of the width direction groove, drainage performance in the sole bottom surface 5s can be improved.
REFERENCE SIGNS LIST
[0065] 1 athletic prosthetic leg
[0066] 2 leg portion
[0067] 2a straight portion
[0068] 2b, 2c curved portion
[0069] 3 curved portion
[0070] 4 ground contact portion
[0071] 4s ground contact region
[0072] 5 sole
[0073] 5s sole bottom surface
[0074] 10 width direction land portion
[0075] 10s contact patch
[0076] 10Wa, 10Wb side wall
[0077] 20 width direction groove
[0078] 100, 110, 120, 140 width direction land portion
[0079] 100a, 110a, 120a width direction extending portion
[0080] 100b, 110b, 120b toe side protruding portion
[0081] 100c, 110c, 120c curved portion side protruding portion
[0082] 130A, 130B, 130C sipe
[0083] c1, c2, c10, c20 chamfer
[0084] w1 length of a width direction land portion 10 in a direction orthogonal to an extending direction
[0085] w2, w3 lengths of chamfers c1 and c2 in a direction orthogonal to the extending direction of the width direction land portion 10
[0086] h1 height of the width direction land portion 10 in a Z direction
[0087] h2 height of the chamfers c1 and c2 in the Z direction
[0088] S road surface
[0089] Y direction in which a sole bottom surface 5s extends from a side of a toe T to a side of a curved portion 3
[0090] W width direction of the sole bottom surface 5s which is orthogonal to a Y direction
[0091] Z thick direction of a sole 5