CN218790852U - Flat foot prevention insole - Google Patents

Abstract

The utility model relates to the technical field of insoles, in particular to an insole for preventing flat feet, which comprises an insole body, wherein the upper surface of a half sole area of the insole body is provided with an isolation positioning convex rib for positioning and isolating a big toe and the rest four toes, the position of the big toe of the insole body is arranged in a big toe positioning sinking groove, and the positions of the four toes of the insole body are provided with little toe positioning sinking grooves; the metatarsophalangeal joints of the big toes of the insole body are provided with toe-bending sinking grooves, and the metatarsophalangeal joints of the four toes of the insole body are flat surfaces. The utility model not only can make the front sole and toe have clear and reliable positioning reference on the insole, so that the front sole and toe are restrained, avoid any sliding and prevent diseases such as eversion of the thumb and paronychia; the plantar fascia is appropriately and intermittently tensioned and relaxed by additionally arranging the toe-bending sinking groove, so that the plantar fascia is actively trained and corrected, the atrophy and the degeneration of the plantar fascia are avoided, the dynamic balance of the plantar fascia in relaxation is flexibly realized, and the formation of a normal arch is finally promoted.

Description

Flat foot prevention insole

Technical Field

The utility model relates to an insole technical field, concretely relates to prevention flat-foot insole.

Background

The insole, which is the most closely contacted article with the sole of the human body, functions to maintain the health of the foot and prevent diseases related to the foot, in addition to providing a soft and comfortable feeling to the sole of the foot. Among foot-related ailments, flat feet due to arch collapse, plantar fasciitis, and paronychia are common.

In order to solve the problem of flat foot, a hard arch support structure is usually added at the arch of the insole, so as to improve the support at the arch of the insole and play a role in improving and correcting the arch. The plantar fascia is a connective tissue that runs along the bottom of the foot, from heel to toe, and helps maintain the integrity of the arch and functions as a shock absorber, and also plays a critical role in the mechanism of the winch. Due to the addition of the hard arch support structure, fascia of the sole is changed from an original relatively straight state into a relatively arched and bent state, namely the sole fascia is pressed and tensioned by the added arch support structure, and the tensioning state is passive and continuous. Because of the passive tension state, the muscles and ligaments in the arch are not actively used for balancing the body weight, namely the participation of the plantar fascia is reduced, so that the plantar fascia is atrophied and the like; while in a continuously tensioned state, once the muscles and ligaments in the arch are used to assist in balancing body weight, tensile overload of the plantar fascia is likely to occur, causing over-tension and overstraining of the plantar fascia. Both of these conditions are likely to induce the onset of plantar fasciitis.

In addition, because the front sole and the toe heads lack clear and reliable positioning reference on the existing insole, the sole is not restrained by the reference during walking or sports, and is easy to freely slide on the insole in front, back, left and right directions, so that the toe heads are very easy to jack or wedge into a narrow tip area at the toe heads, the toe heads are mutually extruded together, and diseases such as eversion of the toes, paronychia and the like are easily induced.

Based on the current situation, it is obvious that the method of simply adding the arch support structure at the arch of the insole can not effectively prevent or radically cure the problems of foot flattening, plantar fasciitis and the like, and the diseases of hallux valgus, paronychia and the like can be easily induced due to the lack of a clear and reliable positioning reference in the forefoot area of the insole. Accordingly, there is a need to develop more effective solutions to one or more of the above problems.

Disclosure of Invention

The utility model provides a pair of flat-foot prevention insoles, which not only can enable the front soles and the toes to have clear and reliable positioning reference on the insoles, but also can enable the front soles and the toes to be restrained by the reference, avoid any sliding and effectively prevent diseases such as eversion of the toes and paronychia; and by additionally arranging the toe-bending sinking groove, the muscles and ligaments of the plantar fascia can be moderately and intermittently tensioned and relaxed during walking, so that the active training and correction of the plantar fascia are increased, the atrophy and the degeneration of the plantar fascia are avoided, the plantar fascia is triggered to flexibly realize dynamic balance between relaxations, and the formation of a normal arch is finally promoted.

The technical scheme of the utility model lies in: an insole for preventing flat feet comprises an insole body, wherein the upper surface of a half sole area of the insole body is provided with isolation positioning convex ribs for positioning and isolating a big toe of a foot from the rest four toes.

The isolation positioning convex rib comprises a front extension convex rib used for isolating and positioning a big toe and a second toe of the foot, a big toe positioning convex rib used for positioning the big toe of the foot and a little toe positioning convex rib used for positioning the rest four toes, and the front extension convex rib, the big toe positioning convex rib and the little toe positioning convex rib are converged into a Y-shaped isolation positioning convex rib.

The front end of the front extending convex rib extends to the front end edge of the insole body so as to completely separate the big toe from the second toe. The insole body is arranged in a foot big toe positioning sinking groove corresponding to the part of a foot big toe, the insole body is provided with a little toe positioning sinking groove corresponding to the parts of four toes, and the little toe positioning sinking groove is beneficial to the contraction and force exertion of flexor tendon when the foot is pushed forwards with force.

The insole is characterized in that an elastic supporting sheet is additionally arranged on the bottom surface of the insole body in a matched mode, the elastic supporting sheet is arranged on the bottom surfaces of the arch area and the heel area of the insole body in a covering mode, a through hole is formed in the center of a heel of the elastic supporting sheet, a heel shock pad is embedded in the through hole, the thickness of the heel shock pad is larger than that of the elastic supporting sheet, and the heel shock pad protrudes out of the bottom surface of the elastic supporting sheet. The design is beneficial to improving the buffering and shock-absorbing performance of the insole body. The heel shock absorption performance is improved, the heel is convenient to land first when running, absorption and buffering are realized, excessive upward conduction of the reaction force on the ground is avoided, the knee of a human body is damaged, and the knee cartilage layer is prevented from being worn to cause hyperosteogeny or bone spur.

As mentioned above, the Y-shaped isolation positioning convex rib, the big toe positioning sinking groove and the little toe positioning sinking groove are arranged on the insole body, so that a clear and reliable positioning reference can be provided for the front sole and the toe head of a user, the front sole and the toe head are subjected to reference constraint when the insole is used for walking or moving, the sole is not easy to freely slide on the insole in the front-back, left-right directions, the toe head is prevented from being jacked into or wedged into a narrow end area at the toe head, and therefore diseases such as eversion of the foot thumb, paronychia and the like caused by mutual extrusion of the toe head are avoided.

It should supplement and explain that the location protruding muscle of keeping apart is different from ordinary antiskid protruding muscle or anti-skidding texture, and antiskid protruding muscle or anti-skidding texture mainly play skid-proof effect, and the utility model discloses in the isolation location protruding muscle that designs generally have higher protruding height, aim at laminating and fill the toe space of bending between sole and the toe before, realize the effect of location and isolation.

The sole body is provided with a toe bending sinking groove corresponding to the metatarsophalangeal joint of the big toe, the metatarsophalangeal joint of the four toes corresponding to the sole body is a flat surface, and the flat surface is not an inclined surface with a thick outer side and a thin inner side.

When walking or sports, the front foot taking a step has its impact point in the rear heel area and the rear foot pushes forwards with force, and the metatarsophalangeal joint of the big toe of the rear foot is sunk into the digitorial sinking groove actively, which is favorable for the force application of the front sole area of the rear foot and enhances the advancing grip force, and can guide the automatic dorsad warping of the big toe of the rear foot, meanwhile, the rest four toe heads are in the flat state of cooperative force application, and the little toe positioning sinking groove is favorable for the contraction and force application of the flexor muscle tendon when the foot pushes forwards with force. On one hand, the foot thumb and the rest four toe heads are staggered up and down, and the diseases of hallux valgus, paronychia and the like caused by the mutual transverse extrusion of the foot thumb and the rest four toe heads are avoided; on the other hand, the foot arch correction device is beneficial to actively tensioning muscles and ligaments of a plantar fascia, and drives the heel bone to be folded towards the front sole of the foot, so that the development and formation of the arch are induced, the effects of preventing and correcting the flat arch are achieved, and the formation of the normal arch is promoted. When the hind foot lifts the foot again to make a forward step, the forefoot area of the hind foot stops exerting force, the metatarsophalangeal joint of the big toe of the foot naturally and actively floats up to form a toe bending sunken groove, at the moment, the big toe of the hind foot naturally returns to a straight state from a dorsad warping state, and muscles and ligaments of plantar fascia become loose. The repeated process can ensure that the muscles and ligaments of the plantar fascia can be properly and intermittently tensioned and relaxed, thereby increasing the active training of the plantar fascia, avoiding the atrophy and degeneration of the plantar fascia, triggering the plantar fascia to flexibly realize dynamic balance and finally forming the normal arch.

Preferably, the upper surface of shoe-pad body still covers anti-skidding elastic cloth, through configuration anti-skidding elastic cloth not only be favorable to cooperating Y font isolation location protruding muscle and foot big toe location heavy groove and little toe location heavy groove to fix a position preceding sole, can also utilize self elasticity to assist the metatarsophalangeal joint of foot big toe in bend the sinking and the come-up of toe heavy groove department to and because anti-skidding elastic cloth covers on bending the toe heavy groove, be favorable to avoiding bending the toe heavy groove because of externally exposing and store up the dirt scheduling problem easily like this, it is convenient to wash, also can avoid the bacterium to store up and breed.

Preferably, a front sole shock pad is arranged on the bottom surface of the front sole of the insole body, and a rear heel shock pad is arranged on the bottom surface of the rear heel of the insole body. The design is favorable for improving the buffering and shock-absorbing performance of the insole body. The heel shock absorption performance is improved, the heel is convenient to land first when running, absorption and buffering are realized, excessive upward conduction of the reaction force on the ground is avoided, the knee of a human body is damaged, and the knee cartilage layer is prevented from being worn to cause hyperosteogeny or bone spur.

Preferably, the elastic support sheet extends backwards from the joint of the arch and the front sole to the tail end of the rear heel and forms an integral cup-shaped package for the rear heel, an inner side sinking groove is longitudinally formed in the bottom surface of the elastic support sheet corresponding to the inner side longitudinal arch, an outer side sinking groove is longitudinally formed in the bottom surface of the elastic support sheet corresponding to the outer side longitudinal arch, so that the elasticity and the flexible deformation and resetting capability of the inner side and the outer side of the elastic support sheet are improved, and a plurality of transverse sinking grooves are transversely formed from the inner side sinking groove of the elastic support sheet to the edge of the inner side sinking groove of the elastic support sheet, so that the flexibility of the inner side longitudinal arch of the elastic support sheet is further improved.

The elastic supporting sheet is different from the traditional hard supporting sheet, has higher elasticity and flexibility, is beneficial to arch auxiliary supporting and heel semi-wrapping auxiliary supporting and protecting when standing, is convenient for transferring and distributing the weight of a human body, increases the effective gravity conduction contact area, and can reduce the local pressure of the insole, so that the insole is not easy to deform. When the insole is applied to the insoles for children, the insole is also beneficial to supporting and limiting the skeleton of the feet of the children, and plays a role in correcting the skeleton.

The beneficial effects of the utility model reside in that: the utility model discloses a set up Y font isolation location protruding muscle and foot big toe location heavy groove and little toe location heavy groove on the shoe-pad body and can provide clear and definite and reliable location benchmark for user's preceding sole and toe head, when walking or motion, let preceding sole and toe head receive the benchmark restraint, make the sole be difficult to freely slide all around on the shoe-pad, avoid the toe head to push up or wedge in that comparatively narrow and small tip region of toe cap department in, thereby avoid bringing out the thumb to turn up easily because of toe head extrudees each other, diseases such as paronychia. The utility model discloses an add the heavy groove of toe of crouching, when walking or motion, can let muscle and the ligament of sole manadesma can be by moderate degree, tension intermittently and lax, increase the initiative training and the correction of sole manadesma, avoid its atrophy and degradation to trigger sole manadesma and realize dynamic balance between lax in a flexible way, finally promote the formation of normal arch of foot.

Drawings

Fig. 1 is a front view structure diagram of an insole for preventing flat feet in the embodiment.

FIG. 2 is a schematic view of the cross-sectional structure A-A in FIG. 1.

Fig. 3 is a rear view structure diagram of the insole for preventing flat feet in the embodiment.

Fig. 4 is a schematic diagram of the bones and muscles of the foot with the ball of the foot flat against the ground.

Fig. 5 is a schematic diagram of the change of the bones and muscles of the foot under the guidance of the corrective insole of the present invention.

In the figure: 1-insole body, 2-isolation positioning convex rib, 2.1-front extension convex rib, 2.2-big toe positioning convex rib, 2.3-little toe positioning convex rib, 3-foot big toe positioning sinking groove, 4-little toe positioning sinking groove, 5-toe bending sinking groove, 6-front sole shock pad, 7-rear heel shock pad, 8-elastic supporting sheet, 8.1-inner side sinking groove, 8.2-outer side sinking groove, 8.3-transverse sinking groove, 9-anti-skid elastic cloth;

11-plantar fascia, 12-flexor brevis tendon, 13-proximal phalanx, 14-metatarsophalangeal joint, 15-metatarsal, 16-talus, 17-calcaneus, 18-fat pad, 19-metatarsophalangeal joint dorsi curvature, 20-medial arch curvature increase, 21-calcaneus and metatarsal spacing shortening.

Detailed Description

In order to make the technical content of the present invention comprehensible to those of ordinary skill in the art, the present invention is described in detail below with reference to the accompanying drawings.

Example 1

As shown in figure 1, the insole for preventing flat feet comprises an insole body 1, wherein an isolation positioning convex rib 2 for positioning and isolating a big toe of a foot from the other four toes is arranged in a half sole area of the insole body 1. The isolation positioning convex rib 2 comprises a front extension convex rib 2.1 used for isolating and positioning a big toe and a second toe, a big toe positioning convex rib 2.2 used for positioning the big toe and a little toe positioning convex rib 2.3 used for positioning the rest four toes, the front extension convex rib 2.1, the big toe positioning convex rib 2.2 and the little toe positioning convex rib 2.3 are jointly converged into the isolation positioning convex rib 2 in a Y shape, and the isolation positioning convex rib 2 is in a structure integrally formed with the insole body 1. The front end of the front extension rib 2.1 extends to the front end edge of the insole body 1 and is flush with the front end edge so as to completely isolate the big toe (i.e. the first toe) and the second toe of the foot of the user. The sole body 1 is arranged in a foot big toe positioning sinking groove 3 corresponding to the part of a foot big toe, the sole body 1 is provided with a little toe positioning sinking groove 4 corresponding to the part of four toes, the little toe positioning sinking groove 4 can be respectively provided with four little toe positioning sinking grooves, or the four little toe positioning sinking grooves which are respectively arranged can be converged into a whole little toe positioning sinking groove. The little toe positioning sunken groove 4 is beneficial to the contraction, bending and force of the flexor tendon of the little toe when the foot is pushed forwards with force.

As mentioned above, the Y-shaped isolation positioning convex rib 2, the big toe positioning sinking groove 3 and the little toe positioning sinking groove 4 are arranged on the insole body 1, so that a clear and reliable positioning reference can be provided for the front sole and the toe head of a user, when the insole walks or moves, the front sole and the toe head are restrained by the reference, the sole is not easy to freely slide on the insole in all directions, the toe head is prevented from being jacked or wedged into a narrow end head area at the toe head, and therefore diseases such as hallux valgus, paronychia and the like caused by mutual extrusion of the toe heads are avoided.

The sole body 1 is provided with a toe bending sinking groove 5 corresponding to the metatarsophalangeal joint of the big toe of a foot, the depth of the toe bending sinking groove 5 is convenient for the metatarsophalangeal joint of the big toe to sink into and cause the front end of the big toe to tilt, the metatarsophalangeal joints of the sole body 1 corresponding to four toes are flat surfaces, the flat surfaces are not high at the outer side and low at the inner side to form a slope structure with the outer height and the inner side, although the slope structure has a correcting acting force on the foot varus or O-shaped leg of a patient, the normal tissue structure of the foot can be recovered after long-term use, the heel keeps the middle position, and the stress deviation of the knee joint caused by the foot varus or the O-shaped leg is corrected. However, such a slope structure is very disadvantageous for the use of patients with flat feet or eversion of feet, and in order to avoid such adverse reactions, the metatarsophalangeal joints of the insole body 1 corresponding to four toes are flat surfaces.

Referring to fig. 4 and 5, when walking or exercising, the front foot taking a step has its force point in the rear heel area and its force point in the front sole area of the rear foot pushing forward with force, at this time, the metatarsophalangeal joint of the big toe of the rear foot will sink down into the sunken groove 5 actively, which not only facilitates the force application in the front sole area of the rear foot and enhances the advancing grip force, but also guides the automatic dorsiflexion of the big toe of the rear foot, at the same time, the rest four toe heads are in the flat state with the coordinated force application, and the sunken groove 4 for little toe positioning is beneficial to the contraction and force application of the tendons of the short flexor when the foot is pushed forward with force. On one hand, the foot sole is beneficial to the up-and-down staggering of the big toe and the rest four toe heads, and the diseases of hallux valgus, paronychia and the like caused by the mutual transverse extrusion of the big toe and the rest four toe heads are avoided; on the other hand, the foot arch correction device is beneficial to actively tensioning muscles and ligaments of a plantar fascia, and drives the heel bone to be folded towards the front sole of the foot, so that the development and formation of the arch are induced, the effects of preventing and correcting the flat arch are achieved, and the formation of the normal arch is promoted. When the hind foot lifts the foot again to make a forward step, the forefoot area of the hind foot stops exerting force, the metatarsophalangeal joint of the big toe naturally and actively floats up out of the bent toe sinking groove 5, at the moment, the big toe of the hind foot naturally returns to a straight state from a dorsad warped state, and muscles and ligaments of the plantar fascia become loose. The repeated process can ensure that the muscles and ligaments of the plantar fascia can be properly and intermittently tensioned and relaxed, thereby increasing the active training of the plantar fascia, avoiding the atrophy and degeneration of the plantar fascia, triggering the plantar fascia to flexibly realize dynamic balance and finally forming the normal arch.

Example 2

As shown in fig. 1 and 2, on the basis of embodiment 1, the upper surface of the insole body 1 is further covered with an anti-slip elastic cloth 9, the anti-slip elastic cloth 9 is configured to be not only favorable for matching with the Y-shaped isolation positioning convex rib 2, the big toe positioning sinking groove 3 and the little toe positioning sinking groove 4 to position the front sole of the foot, but also utilize the elasticity of the anti-slip elastic cloth 9 to assist the metatarsophalangeal joint of the big toe to sink and float at the bent toe sinking groove, and the anti-slip elastic cloth 9 covers the bent toe sinking groove, so that the problem that dirt is easily accumulated in the bent toe sinking groove due to the outward exposure is favorably avoided, the cleaning is convenient, and the accumulation and breeding of bacteria are also avoided.

Example 3

As shown in fig. 3, in addition to embodiment 1 or 2, a forefoot cushion 6 is provided on the bottom surface of the forefoot portion of the insole body 1, and a heel cushion 7 is provided on the bottom surface of the heel portion of the insole body 1. Such a design contributes to improvement of cushioning and shock-absorbing performance of the insole body 1. The heel shock absorption performance is improved, the heel is convenient to land first when running, absorption and buffering are realized, excessive upward conduction of the reaction force on the ground is avoided, the knee of a human body is damaged, and the knee cartilage layer is prevented from being worn to cause hyperosteogeny or bone spur.

Example 4

As shown in fig. 3, in addition to embodiment 1 or 2, a forefoot cushion 6 is provided on the bottom surface of the forefoot portion of the insole body 1, and a heel cushion 7 is provided on the bottom surface of the heel portion of the insole body 1. Under the condition that additional auxiliary support is needed at the arch of foot, the bottom surface of the insole body 1 can be considered to be additionally provided with the elastic support sheet 8 in a matched mode, the bottom surfaces of the arch area and the heel area of the insole body 1 are provided with the elastic support sheet 8 in a covering mode, the center of a heel of the elastic support sheet 8 is provided with a through hole, the through hole is internally embedded with the heel shock pad 7, and the thickness of the heel shock pad 7 is larger than that of the elastic support sheet, namely the heel shock pad protrudes outwards out of the bottom surface of the elastic support sheet. The design is beneficial to improving the buffering and shock-absorbing performance of the insole body. The heel shock absorption performance is improved, the heel is convenient to land first when running, absorption and buffering are realized, excessive upward conduction of the reaction force on the ground is avoided, the knee of a human body is damaged, and the knee cartilage layer is prevented from being worn to cause hyperosteogeny or bone spur.

Or when the insole body 1 is poured, the pouring material of the insole body 1 penetrates through the heel center of the elastic support sheet 7 to form the heel shock pad 8 which is exposed outwards and protrudes out of the bottom surface of the elastic support sheet.

Example 5

As shown in fig. 3, on the basis of embodiment 1, embodiment 2 or embodiment 4, when additional auxiliary support is needed at the arch of foot, it is considered that an elastic support sheet 8 is additionally provided on the bottom surface of the insole body 1, the elastic support sheet 8 extends from the joint of the arch of foot and the front sole of foot to the end of the rear heel of foot and forms an integral cup-shaped package for the rear heel of foot, an inner sunken groove 8.1 is longitudinally provided on the bottom surface of the elastic support sheet 8 corresponding to the inner longitudinal arch of foot, an outer sunken groove 8.2 is longitudinally provided on the bottom surface of the elastic support sheet 8 corresponding to the outer longitudinal arch of foot, so as to improve the elasticity and flexible deformation and resetting capability of the inner and outer side portions of the elastic support sheet 8, and a plurality of transverse sunken grooves 8.3 are further transversely provided on the edge of the inner sunken groove of the elastic support sheet 8 to further improve the flexibility of the inner longitudinal arch of the elastic support sheet.

The elastic support sheet 8 is different from a traditional hard support sheet, the elastic support sheet 8 has high elasticity and flexibility, is beneficial to arch auxiliary support and heel semi-wrapping auxiliary support and protection when standing, is convenient for transferring and distributing the weight of a human body, increases the effective gravity conduction contact area, and can reduce the local pressure of the insole, so that the insole is not easy to deform. When the insole is applied to the insoles of children, the insole is also beneficial to supporting and limiting the skeleton of the feet of the children, and plays a role in correcting the skeleton.

The above-mentioned only be the embodiment of the present invention, not consequently the limitation of the patent scope of the present invention, all utilize the equivalent structure or equivalent flow transform made of the content of the specification and the attached drawings, or directly or indirectly use in other relevant technical fields, all included in the patent protection scope of the present invention.

Claims (8)

1. An insole for preventing flat feet comprises an insole body and is characterized in that: the upper surface of the half sole area of the insole body is provided with an isolation positioning convex rib for positioning and isolating a big toe of a foot and the rest four toes, the isolation positioning convex rib comprises a front extension convex rib for isolating and positioning the big toe and the second toe of the foot, a big toe positioning convex rib for positioning the big toe of the foot and a little toe positioning convex rib for positioning the rest four toes, and the front extension convex rib, the big toe positioning convex rib and the little toe positioning convex rib are converged into a Y-shaped isolation positioning convex rib; the sole body is provided with a toe bending sinking groove corresponding to the metatarsophalangeal joint of the big toe of a foot, and the sole body is a flat surface corresponding to the metatarsophalangeal joint of the four toes; the bottom surfaces of the arch area and the heel area of the insole body are provided with elastic supporting sheets, and the bottom surface of the heel position of the insole body is provided with a heel shock pad.

2. The insole of claim 1, wherein: the front end of the front extending convex rib extends to the front end edge of the insole body so as to completely separate the big toe from the second toe.

3. The insole of claim 1, wherein: the insole body is arranged in the foot big toe positioning sinking groove corresponding to the part of the foot big toe, and the insole body is provided with the little toe positioning sinking groove corresponding to the parts of the four toes.

4. The insole of claim 1, wherein: the upper surface of the insole body is also covered with anti-skidding elastic cloth.

5. The insole for preventing flat feet according to claim 1, wherein: the bottom surface of the front sole of the insole body is provided with a front sole shock pad.

6. The insole of claim 1, wherein: the heel shock-absorbing pad is characterized in that a through hole is formed in the center of the heel of the elastic supporting sheet, a heel shock-absorbing pad is embedded in the through hole, and the thickness of the heel shock-absorbing pad is larger than that of the elastic supporting sheet.

7. The insole of claim 1, wherein: the elastic supporting sheet extends from the joint of the arch and the front sole to the tail end of the heel and forms integral cup-shaped package for the heel.

8. The insole of claim 1, wherein: the bottom surface of the elastic support sheet is longitudinally provided with an inner side sinking groove corresponding to the inner side longitudinal arch, and the bottom surface of the elastic support sheet is longitudinally provided with an outer side sinking groove corresponding to the outer side longitudinal arch so as to improve the elasticity and flexible deformation and resetting capability of the inner side edge part and the outer side edge part of the elastic support sheet; and a plurality of transverse sinking grooves are transversely arranged from the inner side sinking groove of the elastic supporting sheet to the edge of the inner side sinking groove, so that the flexibility of the longitudinal arch of the inner side of the elastic supporting sheet is further improved.

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