GB2492864A

GB2492864A - Footwear with a rotational sole portion

Info

Publication number: GB2492864A
Application number: GB201205898A
Authority: GB
Inventors: Philip David Muirhead
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-07-07
Filing date: 2012-04-02
Publication date: 2013-01-16
Anticipated expiration: 2032-04-02
Also published as: GB2492864B; GB2492587A; GB201111653D0; GB201205898D0

Abstract

An article of footwear comprises an upper 110 with a sole attached to it. The sole is split into first 100 and second 10 portions, with the first portion 100 being fixedly attached to the upper 110 and the second portion 10 being rotatably connected beneath the fixed portion 100 by a spindle 80. Application of a twisting force, exceeding a pre-determined limit, to the rotatable portion 10 permits it to rotate relative to the first portion 100. A deformable, flexible material 120 engaged by a fixed portion 100 and surrounding the rotatable portion 10 will bias the second porÂtion 10 to return to a central position after removal of the twisting force.

Description

ARTICLE OF FOOTWEAR

Field of the Invention

The present invention provides an article of footwear to assist recovery from lower limb injuries and to prevent such injuries from occurring.

Background to the Invention

Many sports, such as soccer, rugby, basketball, baseball and tennis, amongst others, require the athlete to frequently change direction. This can cause significant stress to muscles, ligaments and tendons which can cause injuries over time. It is not uncommon for athletes to also suffer more traumatic injuries as a result of twisting one's knee or ankle beyond its normal range of movement.

A number of sports, such as soccer, golf, rugby, sprinting and cross country, amongst others, utilise footwear having spikes, studs or other means of improving traction. Properly fitting sports shoes do not allow the foot to substan-tially move within the shoe. This is essential to prevent minor injuries such as blisters which can negatively affect performance but can increase the risk of oc- currence of more severe injuries due to the traction means becoming embed-ded in the ground.

Treatment for lower limb injuries usually consists of applying a compres-sion bandage to the injured area and resting. For many people, complete rest is not possible as they may need to work or they may have children to look after. It is often just not convenient to rest for long periods of time in order to recover from injury. Therefore, it is not uncommon for lower limb injuries to cause recur-ring pain and suffering due to more damage being caused by simply carrying on with normal life.

Several attempts have been made to provide solutions to aid in the pre-vention of lower limb injuries. W02007/044451 (NIKE) discloses an article of footwear which has a pivoting sole element. The pivoting sole is an integral part of the shoe and connects to the main part, known as the upper, by way of a de-formable connection.

Upon application of a force exceeding a pre-determined limit, the de-formable connection will permit the sole portion to rotate or tilt relative to the upper. Upon removal of such a force, the deformable connection will revert to its centrally biased position. The rotatable sole portion may be disposed towards either the front or rear of the shoe, or both.

NIKE relies on the chemical structure of the deformable connection to permit rotation of the sole portion in response to application of a force exceed-ing a pre-determined limit. The deformable connection is manufactured from a polymer material and like any other polymer, it will break down over time from repeated use and the structures stability will be compromised by repeated rota-tio n Movement limiters are provided on the fixed sole to prevent the rotatable portion rotating beyond pre-determined limits. These are in the form of moulded portions which are designed to simply prevent further movement of the rotatable portion.

GB2264627 (ZELINKO) discloses a golf shoe having a rotatable front sole portion which is mechanically connected to the sole of the shoe. The rotat- able portion pivots around a central mechanical pivot and is restrained from ro- tating past a certain point by the strength of one or more springs provided be-tween the rotatable sole portion and a spring connected to a mid-sole element.

Upon removal of the force, the rotatable portion will revert to a centrally biased position due to the spring tension. The shoe is further provided with a split in the upper sole element to permit tilting of the shoe in a vertical direction.

GB2425706 (O'DWYER) discloses a football boot having at least one sole portion which is permitted to stretch upon application of a force. Similarly to NIKE, the stretchable sole portions rely on the chemical structure of a polymer to permit stretching and reversion to their original shape.

US2O1 0/0311514 (ANTOLICK) discloses apparatus for attaching to a shoe for assisting in practicing an athlete's swing in sports such as golf or baseball. The apparatus comprises a base plate which is securable to the sole of a shoe, by way of a bolt, a bearing surface and a contact plate for permitting rotation of the shoe relative to the contact plate.

Each of the above documents discloses a solution for assisting the user to rotate their ankle, and or knee, during sports whilst lowering the risk of injury occurring. Each document discloses shoes which are suitable for limited pur-poses, the subject matter disclosed in each could not be freely transferred to other types of shoe.

Summary of the Invention

The present invention provides an article of footwear comprising: an upper; a sole attached thereto, the sole being split into first and second portions, the first portion being fixedly attached to the upper and the second portion being rotatably connected beneath the first portion, whereby application of a twisting force, exceeding a pre-determined limit, to the second portion permits said se-cond portion to rotate relative to the first portion; and a deformable, flexible material engaged by the first portion and surround-ing the second portion, whereby to bias the second portion to return to a central position after removal of the twisting force.

The article of footwear is arranged such that the first portion is an integral part of the shoe. The second portion is split from the first portion and enveloped by an elastic loop connected to opposing sides of the first portion. This serves to disguise the fact that the shoe comprises a split sole and on visual inspection renders the shoe indistinguishable from a shoe of similar style.

The deformable, elastic material advantageously biases the second por-tion in a central position and provides a resistance against rotation such that the second portion will not substantially rotate during low level activities such as walking. The deformable, elastic material further provides an added feature in that it is possible to strike a ball, such as a rugby or football, at a certain power but using less energy than would be required with a standard shoe.

Preferably, the deformable, elastic material will be fixedly attached to each opposing side of the first portion thus enclosing the second portion but permitting rotation relative to the first portion. The deformable, elastic material could also surround the entire circumference of the lower part of the shoe which would be preferable if the sole is split into more than two portions.

The second portion is rotatable by mechanical means to permit con-trolled rotation of the user's ankle thus reducing the risk of injury. Mechanical rotation offers a consistent and repeatable motion putting the user in control of how his ankle rotates in response to stresses on muscles, ligaments and ten-dons.

Preferably, the first portion consists of an upper mounting block, re- cessed to accommodate an upper bearing plate, and a ground engaging por-tion. The second portion preferably consists of a lower mounting block recessed to accommodate a lower bearing plate and a rubber sole.

The rotatable connection is provided by a spindle connecting the first and second portions thus permitting rotation of the second portion around the spin- dle and relative to the first portion. The spindle passes through from the under-side of the second portion and is retained by a nut engaging against the upper surface of the upper mounting block. A gel covering is preferably applied to the upper surface of the upper mounting block to prevent the wearer of the shoes from feeling the nut.

An elastomer is preferably adhesively bonded to the underside of the lower mounting block and sandwiched by a rubber sole adhesively bonded to the underside of the elastomer.

Preferably, at least one of the bearing plates is provided with one or more protrusions extending normally from the bearing surface. The protrusions are received by respective circular grooves in the opposite bearing plate where-by rotation of the rotatable portion is limited by engagement of the protrusions with the edges of the corresponding circular grooves.

To ensure that the rotatable sole feature of the shoes is hardwearing and will last the lifespan of the shoes, the bearing plates will preferably be manufac-tured from metal, carbon fibre or plastic.

Brief Description of the Drawings

In the drawings which illustrate an exemplary embodiment of the inven-tion: Figure 1 shows an isometric cross section of the preferred embodiment of the invention (excluding the elastic loop).

Figure 2 shows an isometric exploded view of the preferred embodiment of the invention (excluding the elastic loop).

Figure 3 shows an illustrative view of a standard shoe incorporating the preferred embodiment of the invention.

Detailed Description of the Illustrated Embodiment

Referring to the figures, Figures 1 and 2 illustrate isometric views of part of the sole of a shoe which is split into first and second portions. The sole forms an integral part of an otherwise standard shoe. A first portion 100 comprises an upper bearing plate 20 recessed within an upper mounting block 30 which forms part of the fixed portion of the shoe.

A second portion 10 comprises a lower bearing plate 40 recessed within a lower mounting block 50 which forms part of the rotatable portion of the shoe.

The upper mounting block 30 is fixedly attached to the upper 100 of a shoe (See Figure 3) by either being glued, stitched, or both, and may be provid-ed with one or more ground engaging portions extending normally therefrom. In the illustrated embodiment, the heel 105 of the shoe is part of the first portion.

The upper bearing plate 20 is of circular cross section and is provided with one or more protrusions 22 (See Figure 2) extending normally from its low-er surface 34. The protrusions are received by corresponding circular grooves 42 in the upper surface 44 of a lower bearing plate 40 which, in combination, permit the lower bearing plate 40 to rotate relative to the upper bearing plate 20 but only to a pre-determined angle set by the length of the circular grooves 42 in the lower bearing plate 40. It will be appreciated that shoes used for different purposes may be provided with bearing plates permitting varying angles of rota-tion.

Each bearing plate 20, 40 sits tight against the upper recessed surface in its respective mounting block 30, 50 and is dimensioned such that the bearing surface 24, 44 of each bearing plate 20, 40 sits proud of its respective mounting block 30, 50.

In use, the upper and lower bearing surfaces 24, 44 will be in permanent mechanical contact. However it will be appreciated that suspension could be provided to ensure that the two bearing surfaces 24, 44 are only in mechanical contact when a user's weight is applied to the shoe. Suspension could be pro-vided by way of a plurality of springs or any other known method.

The second portion 10 is provided with an elastomer 60, sandwiched be-tween the lower mounting block 50 and a rubber sole 70. The elastomer 60 is adhesively bonded to the lower mounting block 50 and sole 70.

The rotation mechanism is held together by the provision of a spindle 80 passing through the second portion 10 from underneath the lower mounting block 50. The spindle 80 passes through both bearing plates 20, 40 and both mounting blocks 30, 50 and is secured by a nut 90 engaging against the upper surface 32 of the upper mounting block 30.

A layer of loam or gel (Not Shown) is applied to the upper surface 32 of the upper mounting block 30 to ensure that the user of the footwear cannot feel the nut 90 as he is walking or otherwise using the shoes.

The illustrated embodiment is provided with a first portion 100 which makes engages the ground at the rear of the shoe. The first portion 100 is fixed- ly attached to the upper 110 by being glued, stitched or both. It will be appreci-ated that alternative embodiments may comprise a first portion which engages the ground in multiple locations along the sole of the shoe.

Figure 3 illustrates that a length of elastic material 120 may be attached to each opposing side of the first portion 100 to retain the second portion 10 and provide an elastic effect to effectively bias the second portion 10 in a central po-sition. The elastic material 120 will be adhesively bonded, stitched, or both, to the first portion 100. It is possible for the elastic material 120 to be replaced if necessary by removing before bonding or stitching a replacement piece of ma-terial 120 to the first 100.

In certain embodiments of the shoe, it may be preferable to utilise an elastic loop to surround the entire circumference of the sole of the shoe. In such an embodiment, the side of the first and second portions will be recessed to as-sist in retaining the elastic loop. The elastic loop would be removable to permit the mechanism of the shoe to be cleaned or otherwise maintained.

It will be appreciated that although a specific embodiment has been de-scribed having a second portion 10 disposed towards the front of the shoe, a shoe could be provided with one or more rotatable portions 10 located in any position on the sole of the shoe.

Claims

<claim-text>CLAIMS1. An article of footwear comprising: an upper; a sole attached thereto, the sole being split into first and second portions, the first portion being fixedly attached to the upper and the second portion being rotatably connected beneath the first portion, whereby application of a twisting force, exceeding a pre-determined limit, to the second portion permits said se-cond portion to rotate relative to the first portion; and a deformable, flexible material engaged by the first portion and surround-ing the second portion, whereby to bias the second portion to return to a central position after removal of the twisting force.</claim-text> <claim-text>2. An article of footwear according to Claim 1, wherein the first por- tion consists of a fixed upper mounting block, recessed to accommodate an up-per bearing plate, and a fixed ground engaging portion, and the second portion consists of a movable lower mounting block recessed to accommodate a lower bearing plate, the first and second portions being connected by a spindle therebetween, thereby permitting rotation of the second portion around the spindle and relative to the first portion.</claim-text> <claim-text>3. An article of footwear according to Claim 2, wherein at least one of the bearing plates is provided with one or more protrusions extending normally from the bearing surface and engaging with circular slots in the bearing surface of the corresponding bearing plate, whereby to limit rotation of the second por-tion to a pre-determined angle relative to the fixed portion.</claim-text> <claim-text>4. An article of footwear according to Claim 2 or 3, wherein the bear-ing plates are manufactured from plastic, carbon fibre or metal.</claim-text> <claim-text>5. An article of footwear according to Claim 2, 3 or 4, further com-prising an elastomer located between the lower mounting block and a rubber sole, whereby, in use, the effort required to walk is reduced by a reaction be-tween the elastomer and the ground.</claim-text> <claim-text>6. An article of footwear according to any preceding claim, wherein the second portion is disposed towards the front of the footwear.</claim-text> <claim-text>7. An article of footwear according to any of Claims 1 to 6, wherein the second portion is disposed towards the rear of the footwear.</claim-text> <claim-text>8. An article of footwear according to any of Claims 1 to 6, wherein two second portions are provided, one disposed toward the front of the footwear and one towards the rear of the footwear.</claim-text> <claim-text>9. An article of footwear according to any preceding claim, wherein the deformable flexible material is a continuous elastic loop applied to the cir-cumference of the sole of an article of footwear.</claim-text> <claim-text>10. An article of footwear according to any of Claims 1 to 8, wherein the deformable flexible material is an elastic strip being fixedly attached to op-posing sides of the fixed portion and surrounding a rotatable portion.</claim-text> <claim-text>11. An article of footwear, substantially as described with reference to, and/or as shown in, the drawings.</claim-text>