Shock-absorbing device disposed in sole of shoe

Abstract

To provide a shock-absorbing device disposed in a sole of a shoe capable of controlling rotational movement of a lower leg during walking in humans having gonarthrosis, and capable of preventing or improving pain and disease states.SOLUTION: A shock-absorbing device 20 is disposed in a sole of a shoe. The sole includes an upper layer 300 made of an elastic body on an upper side, a lower layer 500 made of an elastic body on a ground surface side, and an intermediate layer 400 in which an upper-layer recess 310 and a lower-layer recess 510 having circular, elliptical, or oblong shapes are formed at symmetrical positions between the upper layer and the lower layer, and which is made of a material having a lower elastic modulus than the upper layer and the lower layer, bonded to a lower surface of the upper-layer recess and an upper surface of the lower-layer recess in a gap 450 formed by the upper-layer recess and the lower-layer recess, in such a manner that they contact each other. On respective facing surfaces across the gap between the upper-layer recess and the lower-layer recess, saw blades 314, 514 are formed at positions of extending from a starting point inside the circle, ellipse, or oblong shape toward a peripheral edge of the circle, ellipse, or oblong shape in radial directions and engaging with each other.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a shock-absorbing device disposed within the sole of a shoe, and more particularly to a shock-absorbing device disposed within the sole of a shoe that controls the rotational movement of the lower leg when a person with knee osteoarthritis or other conditions walks, thereby preventing and improving pain and pathological conditions. [Background technology]

[0002] Knee movement involves flexion and extension, and sliding and rolling occurs in the knee joint during flexion and extension. It is said that the load on the knee joint due to flexion and extension during walking can reach three times the body weight. Furthermore, when walking, the knee is subjected to twisting loads of internal and external rotation in addition to flexion and extension. In this way, the knee joint is subjected to a great deal of stress, and this load causes wear, reduction, and deformation of the cartilage within the knee joint, resulting in pain and osteoarthritis.

[0003] When walking, the foot tends to kick off the ground while rotating externally, and if this tendency is strong, it places torsional stress on the knee joint. Patients with osteoarthritis often have abnormal tibial torsion, which is thought to be caused by this torsional stress. Inhibiting or promoting foot rotation can prevent and effectively treat osteoarthritis.

[0004] A technology has been disclosed that reliably suppresses the progression of osteoarthritis of the knee by attaching a device to the bottom of the heel of the shoe sole to induce rotational movement of the knee and generating a gentle rotational torque while reliably mitigating the impact force when the heel touches the ground (see Patent Document 1).

[0005] Furthermore, in order to alleviate the impact load on the knee joint and reduce the burden on the knee joint, a technology has been disclosed in which a gap is formed at the top and / or bottom of the wave-shaped cross section of the sole between the upper and lower layers, and when a load is applied from above, the inclined surfaces that come into contact with each other undergo shear deformation, causing the tissue of the inclined surfaces to shift along the inclined surfaces, thereby promoting shear deformation in addition to compressive deformation due to the load from above and improving cushioning properties (see Patent Document 2).

[0006] Furthermore, a technology has been disclosed in which a rotating body is provided as a means for mitigating impact loads, and when an excessive load is applied, shear deformation occurs in this rotating body, providing a buffering function that absorbs the energy of the impact (Patent Document 3). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 3992724 [Patent Document 2] Patent Publication No. 2007-98181 [Patent Document 3] JP 2003-79402 Summary of the Invention [Problem to be solved by the invention]

[0008] However, in the technology disclosed in Patent Document 1, because the ribs are in direct contact with the road surface, the relationship between the position of the ribs and the road surface can cause the shoe itself to tilt, potentially resulting in an unexpected posture for the pedestrian. Furthermore, the shape of the ribs can change due to wear, etc., and over time, the shoes may no longer meet the intended requirements. Furthermore, pebbles, sand, etc. can be inserted and accumulated between the ribs, potentially causing the shoes to no longer meet the intended requirements. Additionally, although the ribs are spiral-shaped, the direction of rotation is only gently restricted, which could prevent rotation from being restricted in accordance with the symptoms of knee osteoarthritis.

[0009] The technology disclosed in Patent Document 2 does not specify the shape of the corrugations to be engaged, and therefore does not restrict the direction of rotation, potentially making it impossible to restrict rotation according to the condition of knee osteoarthritis. The upper and lower surfaces are directly engaged at the crests and troughs of the corrugations, and the upper and lower layers are only "contacted" but not bonded, which could lead to the accumulation of wear debris and the inability to meet the initial requirements. Furthermore, when subjected to a large external load, deformation beyond the sliding range between the corrugations could occur, for example, over the crests, creating a new engagement, potentially placing a significant burden on pedestrians.

[0010] The technology disclosed in Patent Document 3 is aimed at absorbing the impact of landing, and has grooves formed on the side of the columnar buffer part to encourage rotation, and the deformation of these grooves improves the cushioning properties through shear deformation. Since there is no interlocking structure, the direction of rotation is not restricted, which may make it impossible to restrict rotation according to the state of knee osteoarthritis.

[0011] The present invention has been made in consideration of the above-mentioned circumstances, and can provide a sole member that controls the rotational movement of the lower leg when a person with osteoarthritis of the knee walks, thereby preventing and improving pain and pathological conditions. [Means for solving the problem]

[0012] The present invention is a shock absorber disposed within the sole of a shoe. The sole has: an upper layer made of upper elastic bodies abutted against each other; a lower layer made of an elastic material on the ground surface side; an upper layer recess and a lower layer recess each having a circular, elliptical or oblong shape are formed at symmetrical positions between the upper layer and the lower layer, and an intermediate layer is formed in the gap formed between the upper layer recess and the lower layer recess, the intermediate layer being bonded to the lower surface of the upper layer recess and to the upper surface of the lower layer recess, and the intermediate layer is made of a material having a lower elastic modulus than the upper layer and the lower layer; On the surfaces of the upper layer recess and the lower layer recess facing each other across the gap, saw blades are formed, extending radially from a starting point inside the circle, ellipse or oval to the periphery of the circle, ellipse or oval, and positioned so as to engage with each other.

[0013] This structure has an intermediate layer with a lower elastic modulus than the upper and lower layers between them, which is made of an elastic material. This allows the structure to regulate and absorb shocks and loads applied in the vertical direction, and also regulates the rotation of the knees and ankles, regardless of the unevenness of the ground surface. Furthermore, saw blades are formed on the opposing surfaces of the upper and lower layer recesses, separated by a gap, in a position where they can engage with each other (or in a position where they would intermesh if there was no gap), and by placing an intermediate layer in this gap, the direction of rotation can be regulated.

[0014] According to this configuration, the provision of the intermediate layer can prevent sudden and excessive loads from being placed on the knee joint when patients with knee osteoarthritis walk or stand on rough roads or when carrying heavy objects. Furthermore, by restricting the direction of rotation, compressive and torsional stresses can be alleviated, allowing the normal direction of knee rotation to be achieved when walking or standing, depending on the state of knee osteoarthritis.

[0015] Thus, compared to Patent Documents 1, 2, and 3, this configuration provides a member in the middle layer that encourages rotation, and by bringing the lower layer into contact with the road surface, it is possible to maintain a stable posture. Furthermore, by providing a rotating middle layer that has a lower elastic modulus than the lower and upper layers, it is possible to prevent wear and damage to the rotation area, and to prevent pebbles, sand, etc. from getting stuck and accumulating in the saw blade. Furthermore, by applying a saw blade, the direction of rotation can be restricted, encouraging the pedestrian to perform normal external rotation.

[0016] In the above configuration, a cylindrical rotation axis is formed at the starting point of the lower layer recess, The saw blade extends radially from the outer periphery of the rotary shaft to the periphery of a circle, ellipse, or oval, The upper layer recess may be configured to have a cylinder formed therein into which a rotation shaft is inserted.

[0017] According to the above configuration, the provision of a rotation axis prevents the rotation from fluctuating, and it is possible to prevent the burden on the foot from being placed on the foot due to an excessively large rotation amount or swinging rotation.

[0018] In the above configuration, the saw blade may be a right-angled trapezoid. With this configuration, the initial rotation is facilitated by providing a portion that reduces the influence of the constraints of the upper and lower saw blades. This allows for a smooth and safe initial rotation of the pedestrian's knee and suppresses large deformation that should be restricted. In addition, when a large load is applied in the vertical direction and a load in the lateral or rotational direction is superimposed on this, the pointed portion of the saw blade is prevented from being damaged.

[0019] In the above-mentioned configuration, an adhesive layer made of an elastic material may be formed on the contact surfaces of the upper layer and the lower layer to bond them together.

[0020] According to the above-mentioned configuration, similar to the intermediate layer, it is possible to regulate and absorb shocks and loads applied in the vertical direction, and also to regulate rotation of the knees and ankles, without depending on the unevenness of the ground surface. This prevents patients with knee arthritis from being subjected to sudden and excessive loads on their knee joints when walking or standing on rough roads or carrying heavy objects.

[0021] The present invention is a shock absorber disposed within the sole of a shoe. The sole is an upper layer made of upper elastic bodies abutted against each other; a lower layer made of an elastic material on the ground surface side; a circular upper layer recess and a circular lower layer recess are formed at symmetrical positions between the upper layer and the lower layer; The upper layer recess includes an upper layer protrusion having a cylindrical lower surface made of an elastic body extending from the upper side to the ground surface side; the lower layer recess has a lower layer protrusion having a cylindrical upper surface of the same diameter as the upper layer protrusion, the lower layer protrusion being made of an elastic body and extending from the ground surface side to the upper side; a cylindrical intermediate layer is formed between the upper and lower layers so as to form a gap between the lower surface of the upper layer convex portion and the upper surface of the lower layer convex portion, which serves as an engagement layer, and is bonded to the lower surface of the upper layer convex portion and the upper surface of the lower layer convex portion so as to form a ring-shaped band portion having a predetermined width from the peripheral side to the center side of the lower surface of the upper layer convex portion and the upper surface of the lower layer convex portion, and is made of a material having a lower elastic modulus than the upper layer convex portion and the lower layer convex portion; A plurality of engaging grooves extending in a circumferential direction and having a predetermined width in a radial direction are formed equally in the band portion of the lower layer convex portion, The band portion of the upper layer convex portion is formed with a protrusion that protrudes vertically toward the lower layer through the engaging layer so as to be received in the engaging groove.

[0022] This configuration has a cylindrical intermediate layer with a lower elastic modulus than the upper and lower convex portions, between which are cylindrical upper and lower convex portions made of elastic material formed in the upper and lower concave portions.This allows the structure to regulate and absorb impacts and loads applied in the vertical direction, and to regulate rotation of the knees and ankles, regardless of the unevenness of the ground surface.

[0023] Here, the cross section of the intermediate layer is made smaller than the diameter of the upper layer convex portion and the lower layer convex portion, and the intermediate layer is arranged so as to provide a band-shaped space around the bonded intermediate layer. An engagement groove extending in the circumferential direction is formed in the band portion of the lower layer convex portion, and a protrusion that fits into this engagement groove is formed on the band portion of the upper layer convex portion, and by engaging the protrusion with the engagement groove, the direction of rotation can be restricted.

[0024] According to this configuration, the provision of the intermediate layer can prevent sudden and excessive loads from being placed on the knee joint when patients with knee osteoarthritis walk or stand on rough roads or when carrying heavy objects. Furthermore, by restricting the direction of rotation, compressive and torsional stresses can be alleviated, allowing the normal direction of knee rotation to be achieved when walking or standing, depending on the state of knee osteoarthritis.

[0025] In this way, this configuration provides the intermediate layer with a member that encourages rotation, and the lower layer with the lower layer convex portion is in contact with the road surface, thereby maintaining a stable posture. Furthermore, by applying an engagement mechanism, the direction of rotation can be restricted, encouraging normal external rotation of the pedestrian.

[0026] More specifically, the protrusions and engagement grooves form a so-called rotation mechanism. When a load is applied to this rotation mechanism, the pillars of the upper convex part move along the grooves of the lower convex part, causing it to rotate. By using an elastic material in the middle layer, when the load on the mechanism is released, the middle layer tries to return to its original shape, and the position of the upper convex part returns to its initial position before the load was applied.

[0027] Because the rotation mechanism is incorporated into the insole, the load applied when walking does not always act perpendicular to the rotation mechanism. Therefore, by designing the protrusions to move along the engagement grooves when rotating, it is possible to prevent the upper layer from tilting and coming off. Also, the rotation angle required for external rotation of the lower leg differs depending on the patient with osteoarthritis, and with a mechanism that uses protrusions and engagement grooves, it is easy to create rotation mechanisms with different rotation angles by adjusting the length of the engagement groove.

[0028] In the above configuration, The protrusion may extend in the circumferential direction with a predetermined width in the radial direction, and the circumferential length may be smaller than the circumferential length of the engagement groove.

[0029] This configuration further restricts the directionality of rotation by matching the shape of the protrusion to the shape of the curved engagement groove, and also restricts the angle of rotation by adjusting the circumferential length of the engagement groove and the circumferential length of the protrusion to suit the condition of the patient with knee osteoarthritis and to prevent strain on walking.

[0030] According to this configuration, by regulating the rotation angle as well as the direction of rotation, compressive and torsional stresses can be alleviated, and a normal knee rotation direction can be achieved when walking or standing, depending on the state of knee osteoarthritis.

[0031] In the above configuration, The protrusion may be in contact with one of the circumferential ends of the engagement groove.

[0032] In this configuration, the direction of rotation can be restricted to either clockwise or counterclockwise rotation by previously bringing the protrusion into contact with one of the ends of the engagement groove.

[0033] According to this configuration, by restricting the direction of rotation, compressive and torsional stresses can be alleviated, and a normal direction of knee rotation can be achieved when walking or standing, depending on the state of knee osteoarthritis.

[0034] In the above configuration, The surface of the protrusion facing the engagement groove may have a mountain shape at one end in the circumferential direction and a slope that descends to the other end in the circumferential direction of the engagement groove.

[0035] In this configuration, when viewed in cross section from the side, the protrusions are trapezoidal or triangular with a slope on the upper side. When a patient walks, loads are applied to the shock absorber in both vertical and rotational directions. Because the middle layer has a lower elastic modulus than the upper and lower layers, the pressure with which the protrusions are pressed against the engagement groove changes depending on the load. Because the protrusions have slopes, they can gradually increase resistance to pressure in the rotational direction.

[0036] According to this configuration, the resistance increases as the rotation approaches its limit in accordance with the patient's condition, thereby realizing safer walking.

[0037] In the above configuration, The engagement groove may have a slope that is deeper at one end in the circumferential direction and becomes shallower at the other end in the circumferential direction.

[0038] In this configuration, when viewed in cross section from the side, the engagement groove is trapezoidal or triangular with a slope on the upper side. When a patient walks, loads are applied to the shock absorber in both vertical and rotational directions. Because the middle layer has a lower elastic modulus than the upper and lower convex portions, the pressure with which the protrusions are pressed against the engagement groove changes depending on the load. Because the engagement groove has a slope, resistance to pressure in the rotational direction can be gradually increased.

[0039] According to this configuration, the resistance increases as the rotation approaches its limit in accordance with the patient's condition, thereby realizing safer walking.

[0040] The shock absorber having the above-described configuration can be provided in the front part or the heel part of the shoe, or both. With this configuration, the shape, size, and rigidity of the material of the saw blade can be adjusted for the front part or the heel part, respectively, to suit the walking condition and leg strength, thereby making it possible to provide a shock absorber that is more suited to the pedestrian. [Effects of the Invention]

[0041] The present invention can provide a shock-absorbing device disposed within the sole of a shoe that controls the rotational movement of the lower leg when a person with knee osteoarthritis walks, thereby preventing and improving pain and pathological conditions. [Brief explanation of the drawings]

[0042] [Figure 1] 1 is a cross-sectional view of a shoe equipped with a shock absorber according to a first embodiment of the present invention. [Figure 2] 1 is a perspective view of an upper layer saw blade formed in an upper layer recess according to a first embodiment of the present invention. FIG. [Figure 3] 1 is a perspective view of a lower layer saw blade formed in a lower layer recess according to a first embodiment of the present invention. FIG. [Figure 4A] 3 is an explanatory side view showing an intermediate layer provided between an upper layer saw blade and a lower layer saw blade according to the first embodiment of the present invention. FIG. [Figure 4B] 1 is a perspective explanatory view showing an intermediate layer provided between an upper layer saw blade and a lower layer saw blade according to a first embodiment of the present invention. FIG. [Figure 5A] 3 is an explanatory view showing the rotational state of an upper layer saw blade, an intermediate layer saw blade, and a lower layer saw blade according to the first embodiment of the present invention, viewed from the upper layer side. FIG. [Figure 5B] 1 is an explanatory view showing a cross section of an upper layer saw blade, an intermediate layer saw blade, and a lower layer saw blade in a rotated state according to a first embodiment of the present invention. FIG. [Figure 6] FIG. 10 is a perspective view of an upper layer saw blade formed in an upper layer recess in which a cylinder for inserting a rotary shaft is formed according to a second embodiment of the present invention. [Figure 7] FIG. 10 is a perspective view of a lower layer saw blade formed in a lower layer recess with a rotary shaft according to a second embodiment of the present invention. [Figure 8] FIG. 11 is a perspective view of upper and lower layer saw blades each having a right-angled trapezoid shape formed in an upper layer recess according to a third embodiment of the present invention. [Figure 9] FIG. 10 is an explanatory view of an adhesive layer formed at the contact portion between the upper layer and the lower layer according to the fourth embodiment of the present invention. [Figure 10] 1 is an explanatory diagram showing a shoe including an intermediate layer according to each embodiment of the present invention, viewed from the bottom with the lower layer removed; [Figure 11] FIG. 10 is a side view of a shock absorber according to a fifth embodiment of the present invention. [Figure 12] FIG. 10 is a perspective view of a shock absorber according to a fifth embodiment of the present invention. [Figure 13] FIG. 10 is a perspective view of an upper layer convex portion according to a fifth embodiment of the present invention. [Figure 14] FIG. 10 is a perspective view of a lower layer convex portion according to a fifth embodiment of the present invention. [Figure 15] FIG. 11 is a plan view illustrating the relationship between an engagement groove and a protrusion according to a fifth embodiment of the present invention. [Figure 16] FIG. 13 is a side cross-sectional view illustrating the relationship between an engagement groove and a protrusion according to a sixth embodiment of the present invention. [Figure 17] FIG. 13 is a side cross-sectional view illustrating the relationship between an engagement groove and a protrusion according to a seventh embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0043] (Description of the First Embodiment) A first embodiment of the present invention will be described below with reference to FIGS. 1 to 5. FIG. 1 is a cross-sectional view of a shoe equipped with a shock absorber according to a first embodiment of the present invention. FIG. 2 is a perspective view of an upper layer saw blade formed in an upper layer recess according to a first embodiment of the present invention. FIG. 3 is a perspective view of a lower layer saw blade formed in a lower layer recess according to a first embodiment of the present invention. FIG. 4A is a side view of an intermediate layer provided between an upper layer saw blade and a lower layer saw blade according to a first embodiment of the present invention. FIG. 4B is a perspective view of an intermediate layer provided between an upper layer saw blade and a lower layer saw blade according to a first embodiment of the present invention. FIG. 5A is an explanatory view of the rotational state of the upper layer saw blade, intermediate layer, and lower layer saw blade according to a first embodiment of the present invention, as seen from the upper layer side. FIG. 5B is an explanatory view of a cross section of the rotational state of the upper layer saw blade, intermediate layer, and lower layer saw blade according to a first embodiment of the present invention.

[0044] The general configuration of a shoe 10 equipped with a shock absorber 20 will be described with reference to Figure 1. The shoe 10 encases the foot with an upper 100 that covers the instep and sides of the foot, and an insole 200 that comes into contact with the sole of the foot. Superimposed below the insole 200 are an upper layer 300 that serves as the midsole and a lower layer 500 that serves as the outsole, facing the ground. The sole refers to the insole 200, the upper layer 300 that serves as the midsole, and the lower layer 500 that serves as the outsole.

[0045] The insole 200 is generally formed by laminating EVA resin material (ethylene-vinyl acetate copolymer resin), polyurethane, polyethylene, and cork materials. The upper layer 300, which serves as the midsole, and the lower layer 500, which serves as the outsole, are made of materials with high elasticity, such as rubber, PVC (polyvinyl chloride), PU (polyurethane), EVA (ethylene vinyl acetate), and cowhide.

[0046] An upper layer recess 310 and a lower layer recess 510, each having a circular, elliptical, or oblong shape, are formed symmetrically between the upper layer 300 and the lower layer 500. A lower surface 312 of the upper layer recess and an intermediate layer 400 bonded to the upper surface 512 of the lower layer recess are formed in a gap 450 formed between the upper layer recess 310 and the lower layer recess 510. The intermediate layer 400 can be made of a material with a lower elastic modulus than the upper layer 300 and the lower layer 500, such as a polyurethane resin or a rubber composition such as natural or synthetic rubber. To form the intermediate layer 400, a gel-like silicone rubber or the like may be injected into the gap 450 and cured and molded. In this case, the gap 450 is filled with silicone rubber, but this does not impair the functionality of this embodiment.

[0047] Furthermore, referring to Figures 2 and 3, on the surfaces of the upper layer recess 310 and the lower layer recess 510 facing each other across the gap 450, upper layer saw blades 314 and lower layer saw blades 514 are formed in positions that extend radially from upper layer starting points 316 and lower layer starting points 516 inside the circle, ellipse, or oval to the periphery of the circle, ellipse, or oval, and engage with each other.

[0048] 4A, the intermediate layer 400 is bonded to the lower surface 312 of the upper layer recess and the upper surface 512 of the lower layer recess so as to fill the gap 450 between the upper layer saw blade 314 and the lower layer saw blade 514. In this way, the shock absorber 20 according to this embodiment has a laminated structure in which the intermediate layer 400, which has a lower elastic modulus than the upper layer saw blade 314 and the lower layer saw blade 514, which have a high elastic modulus, is sandwiched between them.

[0049] The shock absorber 20 has an intermediate layer 400 having a lower elastic modulus than the upper layer 300 and the lower layer 500, between which the upper layer 300 and the lower layer 500 are made of a highly elastic material as shown in FIG. 4A. This allows the shock absorber 20 to regulate and absorb shocks and loads applied in the vertical direction, and also regulate the rotation of the knees and ankles, regardless of the unevenness of the ground surface.

[0050] 4B shows the positional relationship between the upper layer saw blade 314 and the lower layer saw blade 514 when a load is applied to the shock absorber 20 due to walking, standing, or the like and the intermediate layer is elastically compressed, with the intermediate layer 400 omitted to make the relationship between the two easier to see. As shown in FIG. 4B, the upper layer saw blade 314 and the lower layer saw blade 514 are formed on opposing surfaces of the upper layer recess 310 and the lower layer recess 510 with a gap therebetween in a positional relationship such that they engage with each other, and the intermediate layer 400 is disposed in this gap, thereby restricting the directionality of rotation.

[0051] That is, the shock absorber 20 can prevent sudden and excessive loads from being applied to the knee joint of a patient with knee osteoarthritis when walking or standing on rough roads or carrying heavy objects. Furthermore, by mitigating compressive and torsional stress, the normal rotation direction of the knee can be achieved when walking or standing, depending on the state of the knee osteoarthritis.

[0052] 2 and 3, when a circular or elliptical shape has peaks and valleys extending from the center to the outer edge, the size of the peaks and valleys increases from the center to the outer edge. Because the upper layer saw blade 314 and the lower layer saw blade 514 sandwich the middle layer 400, the upper, middle, and lower layers are in a relationship similar to the engagement state shown in FIGS. 4A and 4B. In other words, the valley lines on the upper layer side are protruding, and the valley lines on the lower layer side are recessed, thereby achieving the desired rotation restriction.

[0053] By doing this, the rotational force of the person wearing the shoes is concentrated near the center of the shock absorber 20, and the rotational force due to external forces such as road conditions acts near the outer edge of the shock absorber 20. Comparing the moment of inertia, the outer edge >> the center, so it is easier to rotate against the rotational force generated by the pedestrian themselves, and on the other hand, the force resisting the external force is greater, so it is also possible to suppress turning while walking due to disturbances that the pedestrian does not expect.

[0054] 5A and 5B show the relationship between the rotational states during walking. When the saw blade having the central angle φ shown in FIG. 5A rotates, the intermediate layer 400 is elastically displaced, and as shown in FIG. 5B, the peaks and valleys of the upper layer saw blade 314 and the lower layer saw blade 514 are shifted compared to FIG. 4. In FIG. 5B, the spacing between the upper layer saw blades 314, 514 on the outermost periphery of the intermediate layer 400 is shifted by Wm from the matched spacing Ws. The relational expression for this state is shown in Mathematical Formula 1.

[0055]

number

[0056] The shock absorber 20 can be designed and manufactured after determining the blade angle, number, and elastic modulus of the upper saw blade 314 and the lower saw blade 514 based on Equation 1 and in accordance with the muscular strength and walking speed of the walker, the degree of symptoms of knee osteoarthritis, etc., and can be installed in the shoe 10.

[0057] In this way, the shock absorber 20 induces lower leg rotation through its rotation mechanism, reducing the load on the entire leg and preventing and improving knee osteoarthritis by reducing the load on the leg. In addition, the shock absorber 20 is designed without design limitations and does not slip during long-term use, making it easy for anyone to use continuously.

[0058] (Description of the second embodiment) Next, a second embodiment of the present invention will be described with reference to Figures 6 and 7. Figure 6 is a perspective view of an upper layer saw blade formed in an upper layer recess in which a cylinder for inserting a rotary shaft according to the second embodiment of the present invention is formed. Figure 7 is a perspective view of a lower layer saw blade formed in a lower layer recess in which a rotary shaft according to the second embodiment of the present invention is formed. In the following description, explanations of configurations similar to those of the first embodiment will be omitted, and only different configurations will be described.

[0059] The shock absorber 30 according to the second embodiment differs from the first embodiment in that a cylindrical rotation shaft 528 is formed at a lower layer starting point 526 of a lower layer recess 510, and lower layer saw blades 524 extend radially from the outer periphery of the rotation shaft 528 to the periphery of a circle, ellipse, or oval. In the upper layer recess 310, a cylinder 328 into which the rotation shaft 528 is inserted is formed around the upper layer starting point 326. Then, upper layer saw blades 324 extend radially from the outer periphery of the cylinder 328 to the periphery of a circle, ellipse, or oval.

[0060] In this way, by positioning the rotation shaft 528 so that it is housed in the cylinder 328, it is possible to suppress fluctuations in the rotation of the shock absorber 30. Furthermore, it is possible to suppress the burden on the foot caused by the swinging rotation resulting from the elastic deformation of the mid layer 400.

[0061] (Description of the third embodiment) Next, a third embodiment of the present invention will be described with reference to Fig. 8. Fig. 8 is a perspective view of upper layer saw blades and lower layer saw blades each having a right-angled trapezoid shape formed in an upper layer recess according to the third embodiment of the present invention. In the following description, a description of the same configuration as the first embodiment will be omitted, and only the different configuration will be described.

[0062] The shock absorber 40 according to the third embodiment includes an upper layer saw blade 330 and a lower layer saw blade 530 each having a right-angled trapezoidal shape. By forming the saw blades into a right-angled trapezoidal shape, a portion is provided that reduces the influence of constraint on the saw blade when the upper layer 300 and the lower layer 500 rotate, making it possible to facilitate the initial movement of rotation.

[0063] The configuration of the third embodiment allows for a smooth and safe initial movement when the pedestrian's knee rotates, and suppresses large deformation that should be restricted. It also prevents damage to the pointed portion of the saw blade when a large load is applied in the vertical direction and a lateral or rotational load is superimposed on it.

[0064] (Description of the Fourth Embodiment) Next, a fourth embodiment of the present invention will be described with reference to Fig. 9. Fig. 9 is an explanatory diagram of an adhesive layer formed at the contact portion between the upper layer and the lower layer according to the fourth embodiment of the present invention. In the following explanation, explanations of the same configuration as in the first embodiment will be omitted, and only the different configurations will be described.

[0065] In the fourth embodiment, an elastic adhesive layer 460 that bonds the upper layer 300 and the lower layer 500 is formed on the contact surface between them. This adhesive layer 460 is preferably an adhesive layer made from a rubber composition such as natural rubber, silicone rubber, or synthetic rubber that has a lower elastic modulus than the upper layer 300 and the lower layer 500, similar to the intermediate layer 400.

[0066] The configuration of the fourth embodiment can regulate and absorb shocks and loads applied in the vertical direction and regulate rotation of the knees and ankles, regardless of the unevenness of the ground surface, similar to the intermediate layer 400. Furthermore, it can prevent patients with knee osteoarthritis from receiving sudden and excessive loads on their knee joints when walking or standing on rough roads or carrying heavy objects.

[0067] (Description of the fifth embodiment) Next, a fifth embodiment of the present invention will be described with reference to Figs. 11 to 15. Fig. 11 is a side view of a shock absorber according to the fifth embodiment of the present invention. Fig. 12 is a perspective view of a shock absorber according to the fifth embodiment of the present invention. Fig. 13 is a perspective view of an upper layer according to the fifth embodiment of the present invention. Fig. 14 is a perspective view of a lower layer according to the fifth embodiment of the present invention. Fig. 15 is a plan view illustrating the relationship between an engagement groove and a protrusion according to the fifth embodiment of the present invention. In the following description, explanations of configurations similar to those of the first to fourth embodiments will be omitted, and only different configurations will be described.

[0068] In the shock absorber 50 of the fifth embodiment, the portion of the shock absorber 20 of the first embodiment shown in Figure 1 (the portion surrounded by the dotted line), more specifically, the portion in which the upper layer recess 310 and the lower layer recess 510 having a circular, elliptical or oblong shape are formed at symmetrical positions between the upper layer 300 and the lower layer 500, is limited to a circular shape and replaced with the configuration shown in Figures 11 and 12.

[0069] 11 and 12, the upper layer recess 310 in FIG. 1 is formed with an upper layer protrusion 600 having a cylindrical lower surface made of an elastic material extending from the upper side to the ground surface side, and the lower layer recess 510 is formed with a lower layer protrusion 800 having a cylindrical upper surface of the same diameter as the upper layer protrusion 600 made of an elastic material extending from the ground surface side to the upper side.

[0070] A gap that becomes the engagement layer 750 is generated between the lower surface of the upper layer convex portion 600 and the upper surface of the lower layer convex portion 800. A cylindrical intermediate layer 700 is formed between the upper layer 300 and the lower layer 500, and is bonded to the lower surface of the upper layer convex portion 600 and the upper surface of the lower layer convex portion 800, and is made of a material with a lower elastic modulus than the upper layer convex portion 600 and the lower layer convex portion 800, so as to generate ring-shaped upper layer band portions 610 and lower layer band portions 810 that have a predetermined width from the peripheral side to the center of the lower surface of the upper layer convex portion 600 and the upper surface of the lower layer convex portion 800.

[0071] 13 and 14, a plurality of engaging grooves 820 extending in the circumferential direction and having a predetermined width in the radial direction are formed at equal intervals in the lower layer band portion 810 of the lower layer convex portion 800. The upper layer band portion 610 of the upper layer convex portion 600 is formed with protrusions 620 that protrude vertically toward the lower layer convex portion 800 via the engaging layer 750 so as to be accommodated in the engaging grooves 820.

[0072] In this embodiment, as in the first embodiment, by providing an intermediate layer 700, patients with knee osteoarthritis can prevent sudden and excessive loads from being placed on their knee joints when walking or standing on rough roads or carrying heavy objects.

[0073] Furthermore, because the protrusions 620 are housed in the engagement grooves 820 that extend in the circumferential direction, the rotation direction is restricted to the circumferential direction along the engagement grooves 820. During actual walking, it is conceivable that the center of gravity will move back and forth and side to side, but since the middle layer 700, which has a lower elastic modulus than the upper layer protrusions 600 and the lower layer protrusions 800, deforms and there are gaps provided as the engagement layer 750, the rotational movement is not hindered and at the same time, it is possible to restrict the user from assuming an unnatural posture.

[0074] In this way, this embodiment can maintain a stable posture by providing the intermediate layer 700 with a member that encourages rotation and by bringing the lower layer 500, which includes the lower layer convex portion 800, into contact with the road surface. Furthermore, by applying an engagement mechanism consisting of the engagement groove 820 and the protrusion 620, it is possible to restrict the direction of rotation and encourage the pedestrian to perform normal external rotation.

[0075] The protrusions 620 and the engagement grooves 820 constitute a so-called rotation mechanism. When a load is applied to this rotation mechanism, the protrusions 620 of the upper layer protrusions 600 move along the engagement grooves 820 of the lower layer protrusions 800, causing the mechanism to rotate. By using an elastic material for the intermediate layer 700, the intermediate layer 700 attempts to return to its original shape when the load applied to the mechanism is removed, and the position of the upper layer protrusions 600 returns to the initial position before the load was applied.

[0076] Because this rotation mechanism is incorporated into an insole, the load applied during walking does not always act perpendicularly to the rotation mechanism. Therefore, by designing the protrusions 620 to move along the engagement grooves 820 when rotating, it is possible to prevent the upper layer 300, which includes the upper layer convex portion 600, from tilting and becoming dislodged. Furthermore, the rotation angle required for external rotation of the lower leg differs depending on the patient with knee osteoarthritis, and with a mechanism using the protrusions 620 and engagement grooves 820, it is easy to create a rotation mechanism with different rotation angles by adjusting the length of the engagement grooves 820.

[0077] In addition to adjusting the length of engagement groove 820, this embodiment can arbitrarily restrict the directionality of rotation and the rotation of protrusion 620 within engagement groove 820 by changing the initial position and shape of protrusion 620. For example, as shown in Figure 15A, applying a protrusion 620 that is relatively small relative to engagement groove 820 improves the degree of freedom of rotation and also facilitates swinging movement. Note that engagement groove 820 in Figures 15A, 15B, and 15C is actually a groove with a curvature like an arc, but is drawn as a straight line in the figures.

[0078] 15B, if the protrusion 622 extends circumferentially with a predetermined width in the radial direction and its circumferential length is made shorter than that of the engagement groove 820, the angle of rotation can be restricted. Also, the number of swinging displacement elements can be reduced.

[0079] If the protrusion 624 is configured to initially contact one of the circumferential ends of the engagement groove 820 as shown in FIG. 15C, the direction of rotation can be restricted.

[0080] 15A, 15B, and 15C are all designed to accommodate the condition of the patient with knee osteoarthritis and prevent strain on the knee when walking, and are not limited to these combinations of protrusions and engagement grooves. In Fig. 15C, the protrusion is previously brought into contact with one end of the engagement groove, so that the direction of rotation can be restricted to either right or left rotation. Restricting the direction of rotation relieves compressive and torsional stress, allowing the knee to rotate normally when walking or standing, depending on the condition of the knee osteoarthritis.

[0081] (Description of the Sixth Embodiment) Next, a sixth embodiment of the present invention will be described with reference to Fig. 16. Fig. 16 is a side cross-sectional view illustrating the relationship between the engagement groove and the protrusion according to the sixth embodiment. Note that this embodiment is a modification of the engagement mechanism consisting of the protrusion and engagement groove in the fifth embodiment, and therefore, a description of the same configuration as the fifth embodiment will be omitted, and only the different configuration will be described.

[0082] Referring to Figure 16, in this embodiment, the surface of the protrusion 626 facing the engagement groove 820 has a mountain on one circumferential end and a slope 628 that descends to the other circumferential end of the engagement groove 820.

[0083] As shown in FIG. 16, when viewed from a side cross section, the protrusion 626 of this embodiment has a trapezoidal or triangular shape with a slope 628 on the side facing the engagement groove 820.

[0084] When a patient walks, loads are applied to the shock absorber in both the vertical and rotational directions. Because the intermediate layer 700 has a lower elastic modulus than the upper layer convex portion 600 and the lower layer convex portion 800, the pressure with which the protrusions 626 are pressed toward the engagement grooves 820 changes depending on the load. The protrusions 626 have slopes 628, which allow for a gradual increase in resistance to pressure in the rotational direction. In this way, this embodiment increases resistance as the rotational limit approaches, depending on the patient's condition, allowing for safer walking.

[0085] (Description of Seventh Embodiment) Next, a seventh embodiment of the present invention will be described with reference to Fig. 17. Fig. 17 is a side cross-sectional view illustrating the relationship between the engagement groove and the protrusion according to the seventh embodiment. Note that, like the sixth embodiment, this embodiment is a modification of the engagement mechanism consisting of the protrusion and engagement groove in the fifth embodiment, and therefore, a description of the same configuration as the fifth embodiment will be omitted, and only the different configuration will be described.

[0086] Referring to FIG. 17, the engagement groove 822 of this embodiment has a slope 824 that is deeper at one end in the circumferential direction and becomes shallower at the other end in the circumferential direction.

[0087] In this embodiment, when viewed from a side cross section, the engagement groove 822 has a trapezoidal or triangular shape with a slope on the upper side. When a patient walks, loads are applied to the shock absorber in both the vertical and rotational directions. Because the middle layer 700 has a lower elastic modulus than the upper layer convex portion 600 and the lower layer convex portion 800, the pressure with which the protrusion 620 is pressed toward the engagement groove 822 changes depending on the load. Because the engagement groove 822 has a slope 824, it is possible to gradually increase resistance to pressure in the rotational direction.

[0088] According to this configuration, the resistance increases as the rotation approaches its limit in accordance with the patient's condition, thereby realizing safer walking.

[0089] (Description of Other Embodiments) The shock absorbers 20, 30, 40 according to each of the embodiments of the present invention described above can be provided in the forefoot or heel portion of a shoe, or both, as shown in FIG.

[0090] According to this configuration, the shape, size and material rigidity of the saw blade can be adjusted for the front or heel portion to suit the walking condition and leg strength, thereby making it possible to create a shock absorber that is more suited to the pedestrian.

[0091] As described above, the present invention can provide a shock absorbing device disposed in the sole of a shoe that controls the rotational movement of the lower leg when a person with knee osteoarthritis walks, thereby preventing and improving pain and pathological conditions. Note that the aspects of the present disclosure are not limited to the above-described embodiments, and modifications are possible within the scope of the spirit thereof. [Explanation of symbols]

[0092] 10. Shoes 20, 30, 40, 50...Buffer device 100···Upper 200···Insole 300...upper layer 310 Upper recess 312....Underside of upper recess 314, 324, 330... Upper saw blade 316, 326... Upper layer starting point 328...Cylinder 400...Middle class 450...Gap 500...lower layer 510 Lower recess 512: Upper surface of lower recess 514, 524, 530...lower saw blade 516, 526... Upper layer starting point 528 Rotating shaft 600···Upper convex part 610 Upper belt 620, 622, 624, 626...Protrusion 628, 824... Slope 700...Middle class 750···Engagement layer 800 Lower convex part 810 Lower belt 820, 822... Engagement groove

Claims

1. A shock absorber disposed within the sole of a shoe, The sole is an upper layer made of upper elastic bodies abutted against each other; a lower layer made of an elastic material on the ground surface side; an upper layer recess and a lower layer recess each having a circular, elliptical or oblong shape are formed at symmetrical positions between the upper layer and the lower layer, and a gap formed between the upper layer recess and the lower layer recess is filled with an intermediate layer made of a material having a lower elastic modulus than the upper layer and the lower layer, the intermediate layer being bonded to the lower surface of the upper layer recess and the upper surface of the lower layer recess; A shock absorber characterized in that saw blades are formed on the surfaces of the upper layer recess and the lower layer recess facing each other across the gap, extending radially from a starting point inside the circle, ellipse or oval to the periphery of the circle, ellipse or oval in positions such that they engage with each other.

2. a cylindrical rotation axis is formed at the starting point of the lower layer recess, The saw blade extends radially from the outer periphery of the rotary shaft to the periphery of a circle, ellipse, or oval, 2. The shock absorber according to claim 1, wherein the upper recess has a cylinder formed therein into which a rotation shaft is inserted.

3. 2. The shock absorber of claim 1, wherein the saw blade is a right-angled trapezoid.

4. 2. The shock absorber according to claim 1, wherein an adhesive layer made of an elastic material is formed on the contact surfaces of the upper layer and the lower layer to bond them together.

5. The present invention provides a shock absorber disposed within a shoe sole, comprising: The sole is an upper layer made of upper elastic bodies abutted against each other; a lower layer made of an elastic material on the ground surface side; a circular upper layer recess and a circular lower layer recess are formed at symmetrical positions between the upper layer and the lower layer; The upper layer recess includes an upper layer protrusion having a cylindrical lower surface made of an elastic body extending from the upper side to the ground surface side; the lower layer recess has a lower layer protrusion having a cylindrical upper surface of the same diameter as the upper layer protrusion, the lower layer protrusion being made of an elastic body and extending from the ground surface side to the upper side; a cylindrical intermediate layer is formed between the upper and lower layers so as to form a gap between the lower surface of the upper layer convex portion and the upper surface of the lower layer convex portion, which serves as an engagement layer, and is bonded to the lower surface of the upper layer convex portion and the upper surface of the lower layer convex portion so as to form a ring-shaped band portion having a predetermined width from the peripheral side to the center side of the lower surface of the upper layer convex portion and the upper surface of the lower layer convex portion, and is made of a material having a lower elastic modulus than the upper layer convex portion and the lower layer convex portion; A plurality of engaging grooves extending in a circumferential direction and having a predetermined width in a radial direction are formed equally in the band portion of the lower layer convex portion, A shock absorber characterized in that the band portion of the upper layer convex portion has a protrusion formed thereon that protrudes vertically toward the lower layer through the engaging layer so as to be received in the engaging groove.

6. 6. The shock absorber according to claim 5, wherein the protrusions extend in a circumferential direction with a predetermined width in the radial direction, and the circumferential length of the protrusions is smaller than the circumferential length of the engagement grooves.

7. 7. The shock absorber according to claim 5, wherein the protrusion is in contact with one of the circumferential ends of the engagement groove.

8. The shock absorber according to claim 7, characterized in that the surface of the protrusion facing the engagement groove has a peak at one of the circumferential ends and a slope that descends to the other circumferential end of the engagement groove.

9. 8. The shock absorber according to claim 7, wherein the engagement groove has a slope that is deeper at one end in the circumferential direction and becomes shallower at the other end in the circumferential direction.

10. A shoe comprising the shock absorber according to any one of claims 1 to 9 in a front part, a heel part, or both.

Images