Sole with buffer elements

Abstract

A sole is provided with a plurality of buffer elements embedded in the sole at areas bearing most part of pressure applied to the sole by a wearer' foot. Each of the buffer elements includes a non-magnetic housing having a compressible structure, and two permanent magnets vertically oppositely disposed in the housing. Inner sides of the two permanent magnets have the same polarity to produce a magnetic repulsive force between the two magnets to normally expand the compressible housing to its maximum volume. When the housing is subjected to an external pressure, the magnetic repulsive force between the two magnets supports the housing while allowing the same to elastically deform and absorb a reactive force from the ground, so that a buffer effect is obtained.

Description

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a sole with buffer elements, and more particularly to a sole having buffer elements embedded therein at areas bearing most part of pressure applied to the sole, so that a buffer effect is provided by the sole to protect a wearer's bones and joints at foot and knee against undesired impact and injury during exercises and/or sporting activities.

[0002] To protect wearers from injured feet, ankles, and knees during exercises and/or sporting activities, shoe manufacturers have developed soles made of materials with enhanced elasticity. The elastic soles are compressively deformed to absorb a reactive force from the ground when the wearers jump and contact at feet with the ground again, and therefore reduce the impact on the wearers' feet and joints to avoid athletic injuries.

[0003] Another type of air-cushioned shoe has also been developed to increase the vibration-absorbing ability of the sole. The air-cushioned shoe includes a sole provided with a flat air cushion that is an air chamber in the sole and filled with air. When the air cushion is subjected to an external pressure, the internal air, due to its inherent compressibility, will absorb a part of the reactive force from the ground to reduce the impact on a wearer's foot. Since the volume of air increases with rising temperature, the air cushion is largely affected by the temperature in its structural strength and elastic performance. When the temperature rises, air pressure inside the air cushion increases to relatively reduce the limit value of pressure bearable by the air cushion. That is, it is possible an air cushion in use breaks due to an overly high internal air pressure thereof when the temperature rises. On the other hand, when the temperature significantly lowers, the air cushion will have a largely decreased internal air pressure and accordingly reduced elastic performance and buffer effect.

SUMMARY OF THE INVENTION

[0004] A primary object of the present invention is to provide a sole having buffer elements embedded therein. The buffer element of the present invention has preset structural strength and elastic performance that can be maintained even the sole has been used over a long period of time. The buffer element provides the sole with a highly stable buffer capacity to minimize athletic injuries possibly caused by undesired vibration of and impact on foot.

[0005] The buffer element of the present invention includes a non-magnetic housing and two permanent magnets vertically oppositely disposed in the housing. Inner sides of the two magnets facing toward each other have the same magnetic polarity to produce a magnetic repulsive force between the two magnets. The housing is formed from two parts that are vertically movably connected together through engagement of retaining means with long slots separately correspondingly provided on the two parts. When the housing is subjected to an external pressure, the two parts vertical move relative to each other for the housing to compressively deform within a predetermined extent.

[0006] The compressively deformable housing is normally expanded to its maximum volume by the magnetic repulsive force between the two magnets vertically oppositely disposed in the housing. When the housing is subjected to an external pressure, the magnetic repulsive force supports the housing while allowing the same to compressively deform and absorb a reactive force from the ground. A buffer effect can therefore be achieved.

[0007] In another embodiment of the present invention, the two permanent magnets are attached at outer sides to two identical magnetic seats in the form of a shallow plate having an annular peripheral wall defining an open top. The two magnetic seats are oriented for their open tops to face toward each other. End surfaces of the annular peripheral walls of the two magnetic seats are induced magnetic poles having a polarity reverse to that of the inner sides of the two magnets, so that a magnetic circuit is formed in the housing to provide an increased magnetic repulsive force between the two magnets.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein

[0009] FIG. 1 is a top view of a sole with buffer elements according to the present invention;

[0010] FIG. 2 is an assembled perspective view of a first embodiment of the buffer element of the present invention;

[0011] FIG. 3 is an exploded perspective view of the buffer element of FIG. 2;

[0012] FIG. 4 is a sectional view taken along line 4-4 of FIG. 1;

[0013] FIG. 5 is an exploded perspective view of a second embodiment of the buffer element of the present invention; and

[0014] FIG. 6 is a cross sectional view of the buffer element shown in FIG. 5.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Please refer to FIG. 1 that is a top view of a sole 10 according to the present invention. As shown, the sole 10 is provided with a plurality of buffer elements 20 that are separately embedded in the sole 10 at areas bearing most part of pressure applied to the sole 10, such as a front portion below a wearer's ball of foot, and a rear portion below the wearer's heel.

[0016] Please refer to FIGS. 2 and 3 that are assembled and exploded perspective views, respectively, of a first embodiment of the buffer element 20, and to FIG. 4 that is a cross sectional view taken along line 4-4 of FIG. 1. The buffer element 20 includes a housing 21 made of a non-magnetic material, and two permanent magnets 22, 23 disposed in the housing 21. The two permanent magnets 22, 23 are vertically oppositely disposed in the housing 21 with two sides having the same magnetic polarity facing toward each other, so that the two permanent magnets 22, 23 are always pushed away from each other by a magnetic repulsive force. The housing 21 has a compressible structure and is normally expanded to its maximum volume by the magnetic repulsive force between the two permanent magnets 22, 23. When the housing 21 is subjected to an external pressure, the magnetic repulsive force between the two permanent magnets 22, 23 serves as a support to the housing 21 while allowing the housing 21 to compressively deform under the pressure and absorb a reactive force from the ground. A buffer effect is therefore achieved.

[0017] The housing 21 may be formed from two vertically connected parts, namely, an upper and a lower part 21a, 21b. The upper part 21a of the housing 21 is provided at predetermined positions with a plurality of radially projected retainers 21c, and the lower part 21b of the housing 21 is provided with a plurality of vertically extended long slots 21d corresponding to the retainers 21c, so that the retainers 21c are upward and downward movably received in the long slots 21d when the two parts 21a, 21b are connected to each other. When the housing 21 is subjected to an external pressure, the upper and the lower parts 21a, 21b can vertically move relative to each other, allowing the housing 21 to be compressed by a certain extent. When the external pressure no longer exists, the magnetic repulsive force between the two magnets 22, 23 expands the housing 21 to its maximum volume again.

[0018] In designing the buffer element 20, the physical principle of repulsion between two magnetic poles having the same polarity is employed to provide the buffer element 20 with a predetermined extent of elasticity. Since the magnets 22, 23 can be easily manufactured under precise control to produce a desired magnetic strength, it is possible to precisely set the buffer element 20 to a desired buffer capacity that would not decrease even the buffer element 20 has been used over a long time. That is, even the sole 10 has been used over a period of time, it will have a buffer capacity the same as that it has in a completely new condition. This is an advantage of the present invention superior to the conventional air-cushioned shoes.

[0019] The buffer element 20 embedded in the sole 10 at an area close to the wearer's heel is usually provided with increased buffer capacity to create better vibration-absorbing effect. Moreover, it is preferable to embed more than one buffer element 20 in the sole 10 at an area close to the wearer's ball of foot to evenly support the wearer's sole.

[0020] It is preferable for the magnets 22, 23 to have a magnetic strength not strong enough to reach beyond an outer side of the sole 10 to attract magnetic substances on the ground. Normally, the magnetic strength designed for the magnets 22, 23 is one that can be well isolated from the ground by the housing 21 and the sole 10.

[0021] FIGS. 5 and 6 are exploded perspective and assembled cross sectional views, respectively, of a second embodiment of the buffer element 20 of the present invention. In this second embodiment, the permanent magnets 22, 23 are also vertically oppositely disposed in two parts 21a, 21b of the housing 21 but with their outer sides that face away from each other attached to magnetic seats 30, 31, respectively. The magnetic seats 30, 31 are identical members and are in the form of a shallow plate having an annular peripheral wall defining an open top of the seats 30, 31. The magnetic seats 30, 31 are located behind the magnets 22, 23 with the open tops facing toward each other. End surfaces 30a, 31a of the annular peripheral walls of the magnetic seats 30, 31 are induced magnetic poles having a polarity reverse to that of the inner sides of the magnets 22, 23, so that a magnetic circuit is formed in the housing 21 to increase the repulsive force between the two permanent magnets 22, 23. More specifically, when the inner sides of the magnets 22, 23 are, for example, S poles, the end surfaces 30a, 31a of the annular peripheral walls of the two seats 30, 31 are induced N poles. By providing the two plate-shaped magnetic seats 30, 31, the buffer element 20 may have increased elastic strength. However, it is to be noted that the induced magnetic poles of the magnetic seats 30, 31 are located at the end surfaces 30a, 31a of their annular peripheral walls, and there is not any magnetic field line at outer sides 30b, 31b of the magnetic seats 30, 31. That is, the buffer element 20 with the magnetic seats 30, 31 would absolutely not attract magnetic substances on the ground.

[0022] In brief, the sole with buffer elements according to the present invention has the advantages of being structural strong and highly durable, and can be easily constructed to have any desired buffer capacity.

Claims

1. A sole with buffer elements, comprising a sole and a plurality of buffer elements embedded in said sole at areas that bear most part of pressure applied by a wearer's foot to said sole;

each of said buffer elements including a housing made of a non-magnetic material and having a compressible structure, and two permanent magnets vertically oppositely disposed in said housing with two sides having the same magnetic polarity facing toward each other to produce a magnetic repulsive force between said two permanent magnets; and

said housing being normally expanded by said magnetic repulsive force to a maximum volume thereof.

2. The sole with buffer elements as claimed in claim 1, wherein said housing is formed from two vertically connected parts, a first one of which being provided at predetermined positions with a plurality of radially projected retaining means, and a second one of which being provided with a plurality of vertically extended long slots corresponding to said retaining means, such that said retaining means are upward and downward movably received in said long slots.

3. The sole with buffer elements as claimed in claim 1, wherein said two permanent magnets are respectively attached at outer sides to two magnetic seats, said two magnetic seats being identical to each other and in the form of a shallow plate having an annular peripheral wall defining an open top for each said magnetic seat, and said two magnetic seats being oriented with said open tops facing toward each other.