Sole for protecting knee joint

Abstract

The utility model discloses a sole for protecting knee joints, which comprises a midsole, a plurality of holes extending along the width direction of the midsole are arranged along the length direction of the midsole, and the holes are configured to be capable of being compressed and deformed forwards when a foot touches the ground. The sole provided by the utility model has good cushioning performance, and can effectively reduce the shearing force of the knee joint in the front-back direction when the foot touches the ground, thereby effectively reducing the injury of the knee joint.

Description

Technical Field

[0001] The utility model relates to the technical field of footwear, in particular to a shoe sole for protecting knee joints. Background Art

[0002] Sports shoes are shoes designed and manufactured according to the characteristics of people participating in sports or traveling. Sports shoes are different from ordinary leather shoes and rubber shoes. Their purpose is to reduce injuries and improve sports performance. However, with the improvement of sports shoe manufacturing technology, the incidence of sports injuries has not decreased. Running has become the number one sport because it has a low threshold, is not restricted by venues, and has a good training effect. According to relevant data, among the running population, men (52%) and women (49%) reported at least one lower limb injury in the past 12 months, among which the incidence of knee joint injuries accounts for 42.1% of all injuries.

[0003] At present, in order to reduce knee joint injuries, the design of sports shoes mainly aims to improve the shock absorption of the soles, thereby reducing the ground impact force on the knee joint in the vertical direction during exercise, reducing the impact on the knee joint, and reducing the occurrence of sports injuries. There are two main technical means: 1. Improve the physical properties of the midsole material to improve the shock absorption, but it is mainly restricted by the progress of raw materials; 2. Change the structure of the midsole to absorb the impact of the ground through deformation. However, when running, it is a composite force, and only improving the shock absorption of the sole can provide limited protection for the knee joint. Utility Model Content

[0004] The utility model aims to provide a shoe sole for protecting the knee joint so as to reduce the injury of the knee joint.

[0005] In order to achieve the above-mentioned purpose, the technical solution proposed by the utility model is:

[0006] A sole for protecting knee joints includes a midsole, wherein the area of ​​the midsole corresponding to the forefoot is defined as the forefoot area, the area corresponding to the midfoot is defined as the midfoot area, the area corresponding to the rear foot is defined as the rear foot area, the side corresponding to the inner side of the instep is defined as the inner side, and the side corresponding to the outer side of the instep is defined as the outer side. The midsole is provided with a plurality of holes extending along the width direction of the midsole along its length direction, and the holes are configured to be compressed and deformed forward when the foot touches the ground.

[0007] Preferably, at least the holes in the rear foot area are configured with a cross-section that gradually decreases from the inner side of the midsole to the middle direction, or the holes in the rear foot area are configured with a cross-section that gradually decreases from the inner side of the midsole to the outer side, and the holes in the forefoot area and the midfoot area are configured with a cross-section that gradually decreases from the inner and outer sides of the midsole to the middle direction, and the cross-section of the outer end of the hole is larger than the cross-section of the inner end thereof.

[0008] Preferably, the line segment connecting the two points farthest apart on the outer periphery of the cross-section of the hole is defined as the major axis, and the line segments connecting any point on the major axis and two points on the outer periphery and perpendicular to the major axis are shorter than the major axis. The major axis is higher at the front and lower at the back, and the inclination angle of the major axis relative to the midsole bottom surface is 0° to 50°.

[0009] Preferably, the width of the cross-section of the hole increases first and then decreases from front to back along the major axis direction.

[0010] Preferably, the sizes of the cross-sections of several of the holes increase first and then decrease from front to back.

[0011] Preferably, the inclination angle of the major axis of the hole in the forefoot area relative to the midsole bottom surface is 0° to 5°, the inclination angle of the major axis of the hole in the midfoot area relative to the midsole bottom surface is 25° to 50°, and the inclination angle of the major axis of the hole in the hindfoot area relative to the midsole bottom surface is 3° to 5°.

[0012] Preferably, the inclination angles of the major axes of the cross-sections of several of the holes relative to the midsole bottom surface increase first and then decrease from front to back.

[0013] Preferably, the contour shape of the cross-section of the hole is an asymmetric shape, or the contour shape of the cross-section of the hole is composed of a first arc segment, a third arc segment, a second arc segment, and a fourth arc segment connected end to end in sequence. The first arc segment is located above the front side of the second arc segment, and the width between the two end points of the first arc segment is smaller than the width between the two end points of the second arc segment. The third arc segment is located above the fourth arc segment. The center of curvature of the first arc segment is located below it. The center of curvature of the second arc segment is located in front of it. The centers of curvature of the third arc segment and the fourth arc segment are respectively located behind it.

[0014] Preferably, an elastic support member is provided in the hole.

[0015] Preferably, the midsole is made of any one of supercritical foaming materials such as EVA, ETPU, PEBA, and TPEE. The elastic support member is a spring or an air cushion, or is made of TPU material or nylon material.

[0016] By adopting the above technical solution, the beneficial effect of the present utility model is as follows: The midsole of the present utility model is provided with a plurality of holes extending along the width direction of the midsole along its length direction. The holes are configured to be compressible and deformed forward during the process of the foot landing, which can effectively reduce the shear force of the knee joint in the front-back direction when the foot lands, and thus effectively reduce knee joint injuries. Description of the Drawings

[0017] Figure 1 It is an inner side plan view of the sole of a preferred embodiment of the present utility model.

[0018] Figure 2 is Figure 1 A sectional view of the midsole in the length direction.

[0019] Figure 3 is Figure 1 A diagram of the deformation of the holes when the midsole touches the ground (walking state).

[0020] Figure 4 is Figure 1 A diagram of the change in the position of the center of foot pressure during the process of the midsole touching the ground.

[0021] Figure 5 is Figure 1 A bottom view schematic diagram of the midsole.

[0022] Figure 6 is Figure 1 A fan-shaped diagram of the force measuring platform of the midsole.

[0023] Figure 7 is a schematic cross-sectional view of the holes of another preferred embodiment of the present utility model. Specific embodiments

[0024] The present utility model will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0025] When running and touching the ground, it is a combined force, including both the impact force in the vertical direction and the shear force in the front-back direction. And the important cause of knee joint injury is exactly the shear force it receives. Excessive shear force is likely to cause knee joint bone injury, meniscus injury, etc., and most of these injuries are irreversible. Therefore, the present utility model proposes a midsole that can reduce the shear force on the knee joint in the front-back direction, thereby effectively reducing knee joint injury.

[0026] As Figure 1 shown, the midsole for protecting the knee joint of the present utility model includes a midsole 1. It is known that the foot includes the forefoot, midfoot, and hindfoot. The area of the midsole 1 corresponding to the forefoot is defined as the forefoot area A, the area corresponding to the midfoot is the midfoot area B, the area corresponding to the hindfoot is the hindfoot area C, the side corresponding to the inner side of the instep is the inner side, the side corresponding to the outer side of the instep is the outer side, the direction corresponding to the toes is the front, and the direction corresponding to the heel is the back.

[0027] A plurality of holes 2 are sequentially arranged at intervals along the length direction (i.e., the front-back direction) of the midsole 1. The holes 2 are configured to extend along the width direction of the midsole 1 and can be compressed and deformed forward during the process of the foot touching the ground, so as to reduce the shear force on the knee joint in the front-back direction, thereby reducing knee joint injury.

[0028] Since the force when the foot touches the ground is a combined force, the holes are preferably configured to be compressed and deformed vertically downward and horizontally forward simultaneously during the process of the foot touching the ground, as Figure 3As shown, it can effectively reduce the shear force in the front-back direction and the impact force in the vertical direction of the knee joint, protecting the knee joint.

[0029] The hole 2 can be configured to penetrate the inner wall and / or the outer wall of the midsole 1, or can be configured not to penetrate the midsole 1. The hole 2 can be arranged on the inner side of the midsole 1 or on the outer side of the midsole 1, and is preferably arranged on the outer side.

[0030] In some preferred embodiments of the present invention, the midsole 1 is provided with holes 2 in the forefoot area A, the midfoot area B, and the rearfoot area C.

[0031] The position change of the center of foot pressure during the foot landing process is as Figure 4 shown. The small dots in the figure are the pressure center points. The pressure center points start from the outer side of the rear foot, move forward and inward, and finally leave the ground in the middle of the forefoot. It can be seen that when landing from the outer side of the rear foot, the outer side of the rear foot is the most stressed, while the inner side and the middle of the shoe are mainly stressed relatively more in the midfoot and forefoot. Based on this, the cross-sectional changes of the holes 2 in different regions of the midsole 1 are determined. Combining Figure 5 the following: The hole 2 in the forefoot area A is configured such that its cross-section gradually shrinks from the inner and outer sides of the midsole 1 towards the middle direction, and the cross-section of the outer end of the hole 2 is larger than the cross-section of its inner end. The hole 2 in the midfoot area B is configured such that its cross-section gradually shrinks from the inner and outer sides of the midsole 1 towards the middle direction, and the cross-section of the outer end of the hole 2 is larger than the cross-section of the inner end. The hole 2 in the rearfoot area C is configured such that its cross-section gradually shrinks from the inner side of the midsole 1 towards the outer side.

[0032] Since the force is the greatest at the moment of landing during the entire process from foot landing to takeoff, therefore, at least the hole 2 in the rearfoot area C is configured such that its cross-section gradually shrinks from the inner side of the midsole 1 towards the middle direction to reduce the ground impact force in the horizontal direction, thereby reducing the shear force on the knee joint at the moment of landing, and further reducing knee joint injuries. Of course, it is preferably to configure the holes in each region according to the cross-sectional changes of the holes in the aforementioned regions to protect the knee joint throughout the process from foot landing to takeoff.

[0033] Through finite element simulation and high-speed photography, it can be known that for symmetric holes such as circular holes, the deformation in the vertical direction is relatively large, the change in the front-back direction is relatively small, and the inclination angle cannot be well set. Therefore, the deformation in the horizontal direction is small, and the horizontal shear force cannot be effectively relieved. Therefore, in some preferred embodiments of the present invention, the hole 2 adopts an asymmetric shape, such as an oval-like shape, a waist-like shape, an egg-like shape, a pear-like shape, etc. The hole 2 can be inclined, so that there is a large deformation in the horizontal direction b.

[0034] Refer to Figure 7, in another preferred embodiment of the present utility model, the contour shape of the cross-section of the hole 2 is composed of a first arc segment 21, a third arc segment 23, a second arc segment 22, and a fourth arc segment 34 that are connected end to end in sequence. The first arc segment 21 is located above the front side of the second arc segment 22, and the width between the two end points of the first arc segment 21 is smaller than the width between the two end points of the second arc segment 22. The third arc segment 23 is located above the fourth arc segment 24. The center of curvature of the first arc segment 21 is located below it, the center of curvature of the second arc segment 22 is located in front of it, and the centers of curvature of the third arc segment 23 and the fourth arc segment 24 are respectively located behind it.

[0035] Referring to Figure 1 , the line segment connecting the two points farthest apart on the outer periphery of the cross-section of the hole 2 is defined as the major axis 3. The line segment 4 connecting any point on the major axis 3 and two points on the outer periphery and perpendicular to the major axis 3 is shorter than the major axis 3. The inclination angle α of the major axis 3 relative to the midsole bottom surface 5 is 0° to 50°.

[0036] The width of the cross-section of the hole 2 first increases and then decreases from front to back along the direction of the major axis 3, making the hole 2 wider at the top and narrower at the bottom, which is beneficial to increasing its deformation in the horizontal direction b and reducing the horizontal shear force.

[0037] As Figures 1 to 3 shown, the shapes and sizes of the holes 2 in the midsole 1 of this embodiment are different. There are relatively symmetrical ellipses and asymmetrical ovals. The hole 2 can deform in the vertical direction a, thereby reducing the ground reaction force in the vertical direction a. Due to the asymmetry of the hole 2, after landing, its upper part can slide forward and deform, so that when the sole does not move on the ground, the upper part of the sole can slide forward within a small range, thereby increasing the action time in the horizontal direction b and reducing the ground impact force in the horizontal direction b, effectively reducing the shear force of the knee joint and reducing knee joint injuries. The size of the hole 2 should not only meet the needs of shock absorption and knee joint protection but also have sufficient support. Therefore, in some preferred embodiments of the present utility model, from front to back, the cross-sectional sizes of the holes 2 in the midsole 1 first increase and then decrease.

[0038] In some preferred embodiments of the present utility model, the inclination angles of the holes 2 are not equal. By measuring the direction and magnitude of the ground reaction force measured by the force platform during the foot contact period of running, as Figure 6 shown, to determine the inclination angle of the hole 2.

[0039] Referring to Figure 1 and Figure 2, in a preferred embodiment of the present utility model, the major axis 3 of the holes 2 in each region has a different inclination angle α with respect to the bottom surface 5 of the midsole. The inclination angle of the holes 2 in the forefoot region A is 0° to 5°, the inclination angle of the holes 2 in the midfoot region B is 25° to 50°, and the inclination angle of the holes 2 in the hindfoot region C is 3° to 5°. From front to back of the midsole 1, the inclination angle α of each hole 2 first increases and then decreases.

[0040] The midsole 1 of some preferred embodiments of the present utility model is made of any one of supercritical foaming materials such as EVA (ethylene-vinyl acetate), ETPU (expanded thermoplastic polyurethane), PEBA (polyether block amide), and TPEE (thermoplastic polyester).

[0041] In some preferred embodiments of the present utility model, an elastic support member is provided in the hole 2. The elastic support member can be made of TPU (thermoplastic polyurethane) material or nylon material, or a spring or an air cushion can also be selected.

[0042] Through biomechanical comparative tests on the prototype shoes in the laboratory, it is found that the prototype shoes with an asymmetric hole structure of the present utility model have a shear force 16.1% smaller (41.7N VS 49.7N) in the front-back direction of the knee joint horizontal plane compared to the shoes with circular holes.

[0043] The structural design of the sole of the present utility model determines the core parameters such as the shape, size, and inclination angle of the holes 2 by studying the movement laws of walking and running and the anatomical characteristics of the human body, through means such as high-speed photography, force platform, plantar pressure plate, and finite element simulation, so as to buffer the vertical ground reaction force and the shear force in the horizontal direction to the greatest extent while ensuring the support of the sole, thereby reducing the damage to the knee joint.

[0044] Although the present utility model is specifically shown and described in conjunction with the preferred embodiments, those skilled in the art should understand that various changes in form and details made to the present utility model without departing from the spirit and scope of the present utility model defined by the appended claims are within the protection scope of the present utility model.

Claims

1. A shoe sole for protecting the knee joint, characterized in that: Including a midsole, wherein the area of ​​the midsole corresponding to the forefoot is set as the forefoot area, the area corresponding to the midfoot is set as the midfoot area, the area corresponding to the hindfoot is set as the hindfoot area, the side corresponding to the inner side of the instep is set as the inner side, and the side corresponding to the outer side of the instep is set as the outer side; The midsole is provided with a plurality of holes along its length direction and extending along the width direction of the midsole. The holes are configured to be compressed and deformed forward during the foot landing process.

2. The shoe sole for protecting the knee joint according to claim 1, characterized in that: At least the holes in the rear foot area are configured such that the cross section gradually decreases from the inner side of the midsole to the middle. or, The holes in the rear foot area are configured to gradually decrease from the inner side of the midsole to the outer side; The holes in the forefoot area and the midfoot area are configured such that the cross section gradually decreases from the inner and outer sides of the midsole to the middle, and the cross section at the outer end of the hole is larger than the cross section at the inner end.

3. The shoe sole for protecting the knee joint according to claim 1, characterized in that: The line segment connecting the two points on the periphery of the cross section of the hole that are farthest apart is defined as the major axis, and the line segment connecting any point on the major axis and two points on the periphery and perpendicular to the major axis is shorter than the major axis; The long axis is higher in the front and lower in the back, and the inclination angle of the long axis relative to the bottom surface of the midsole is 0° to 50°.

4. The shoe sole for protecting the knee joint according to claim 3, characterized in that: The width of the cross section of the hole increases first and then decreases from front to back along the long axis direction.

5. The shoe sole for protecting the knee joint according to claim 3, characterized in that: The cross-sectional sizes of the plurality of holes increase first and then decrease from the front to the back.

6. The shoe sole for protecting the knee joint according to claim 3, characterized in that: The inclination angle of the long axis of the hole in the forefoot area relative to the bottom surface of the midsole is 0° to 5°; The long axis of the hole in the midfoot area has an inclination angle of 25° to 50° relative to the bottom surface of the midsole; The inclination angle of the long axis of the hole in the rear foot area relative to the bottom surface of the midsole is 3° to 5°.

7. The shoe sole for protecting the knee joint according to any one of claims 3 to 6, characterized in that: The inclination angles of the major axes of the cross sections of the plurality of holes relative to the bottom surface of the midsole first increase and then decrease from front to back.

8. The shoe sole for protecting the knee joint according to any one of claims 1 to 6, characterized in that: The cross-sectional profile of the hole is an asymmetric shape; or, The contour shape of the cross section of the hole is composed of a first arc segment, a third arc segment, a second arc segment and a fourth arc segment connected end to end in sequence; the first arc segment is located above the front side of the second arc segment, and the width between the two end points of the first arc segment is smaller than the width between the two end points of the second arc segment, the third arc segment is located above the fourth arc segment, the center of curvature of the first arc segment is located below it, the center of curvature of the second arc segment is located in front of it, and the centers of curvature of the third arc segment and the fourth arc segment are respectively located on the rear side thereof.

9. The shoe sole for protecting the knee joint according to any one of claims 1 to 6, characterized in that: An elastic supporting piece is arranged in the hole.

10. The shoe sole for protecting the knee joint according to claim 9, characterized in that: The midsole is made of any one of supercritical foaming materials including EVA, ETPU, PEBA and TPEE; The elastic support member is a spring or an air cushion, or is made of TPU material or nylon material.

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