FOOT SUPPORT STRUCTURE AND SHOE ASSEMBLY
A foot support structure for a shoe includes a toe box, a connection member facilitating adjustable connection of the toe box to a cooperable connection member on a separate shank portion of a shoe, an opening defined by a peripheral edge of the toe box portion, and a toe box liner lining the inner surface of the toe box portion. The toe box and toe box liner are each moulded from a thermoplastic polymer material and the toe box liner extends beyond the peripheral edge of the toe box at its opposing lateral sides to form foot-supporting side wings; and wherein the thermoplastic polymer material of the toe box has a greater stiffness than that of the toe box liner.
This application claims the benefit of Great Britain Patent Application No. 1311970.6, filed Jul. 4, 2013; the disclosure of which is incorporated herein by reference in its entirety.
FIELDThis disclosure relates to a shoe and particularly, but not exclusively, to a foot support structure and shoe assembly for a dance or performing arts shoe which provides a wearer with enhanced levels of comfort, durability, stability and shock absorption.
BACKGROUNDA dance shoe is disclosed in GB 2 449 821 which has a shank portion connectable with a toe box portion and a detachable outer covering.
In that disclosure, it is stated that during training and performances, ballet dancers are often required to dance upon their toes which is a technique known as “going en pointe” (or “sur les pointes”). Pointe ballet shoes (or toe shoes) have a blocked toe which is generally constructed by hand using layers of fabrics, cardboard, paper or leather saturated with glue as a laminant to form a reinforced toe box joined to a leather or cardboard shank. A reinforced stiffener is generally also included in the shank and the outer sole is constructed from leather. An outer layer of fabric or “upper” is sewn to the sole and usually gathered in pleats under the toe. This design and manner of construction is labour intensive and expensive to produce. Although some improvements to the construction have been proposed, such as those described in U.S. Pat. No. 4,453,996 (Ballet Makers Inc), the design of pointe ballet shoes has generally been unchanged since conception.
Traditional ballet shoes require extensive breaking-in before they are comfortable for use, which typically requires manual flexing, application of force, steaming or soaking in water or alcohol. Once the shoe has been broken-in, it will have a short lifespan and a ballet dancer may use two or three pairs of ballet shoes each week. This short lifespan is due to the deterioration of the toe box and or shank caused by the rapid breakdown of the glue used to form the laminates of the toe box. The breakdown can be accelerated by perspiration during energetic dancing. Once the shank and/or toe box have deteriorated, the shoe is useless because there will be insufficient support for the ballet dancer.
Conventional ballet shoes have a number of drawbacks, for example, the toe box compresses the side of the feet and may exacerbate injuries associated with the hopping and leaping en pointe required by ballet choreography. In addition, ballet shoes are noisy which results from the sound caused by the toe box striking the floor which can often detract from the illusion of effortless grace which a ballet dancer strives. A ballet dancer will often attempt to compensate for the noise by softening the impact on the floor which may detract from the performance or cause injury.
Lateral support in traditional ballet shoes is typically provided by “graduated” portions of progressively reducing thickness in the rearward direction with respect to the toe box portion. The supports are constructed from diminishing layers of a gauze or hessian (burlap) type woven material bonded by a glue-like substance. The major issue with this is that after a relative short period—i.e. significantly less than the overall life span of the remainder of the shoe—these graduated diminishing layers break down thus rendering the shoe ineffective at providing the necessary support to the metatarsal area of the foot.
These considerations are relevant to this disclosure, which seeks to provide a further improved shoe which would be beneficial to ballet dancers, and in general to provide a shoe of improved life span whilst lessening the risk of injury.
SUMMARY OF THE DISCLOSUREAccording to a first aspect of the present invention, there is provided a foot support structure for a shoe comprising:
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- a toe box;
- a connection member facilitating adjustable connection of the toe box to a cooperable connection member on a separate shank portion of a shoe;
- an opening defined by a peripheral edge of the toe box portion; and
- a toe box liner lining the inner surface of the toe box portion;
wherein the toe box and toe box liner are each moulded from a thermoplastic polymer material and the toe box liner extends beyond the peripheral edge of the toe box at its opposing lateral sides to form foot-supporting side wings; and wherein the thermoplastic polymer material of the toe box has a greater stiffness than that of the toe box liner.
The additional side wings of the present disclosure offer side support to a wearer's foot in use. In particular, for a dancer balancing “en pointe” upon the toe box portion, the vertical orientation of the side wings help to support the dancer by improving stability thus reducing fatigue and discomfort.
Optionally, each side wing extends rearwardly away from each lateral side of the toe box by distance lying in the range of 20 mm to 60 mm.
Optionally, the height of each side wing relative to the toe box diminishes with increasing distance from the toe box opening.
Optionally, the thickness of the toe box liner lies in the range of 2.0 mm to 3.0 mm.
In one embodiment, the approximate thickness of the toe box liner is 2.5 mm and remains constant over most of its surface area with the exception that it diminishes—to a thickness of approximately 0.5 mm—along its free edges extending between the side wings, and across the free edges of the side wings themselves.
Optionally, the thickness of each side wing diminishes with increasing distance from the toe box opening.
Optionally, each side wing is formed from a continuation of a unitary piece of thermoplastic elastomer (TPE) material forming the toe box liner.
By providing side wings which are comprised of a single unitary material and are of substantially uniform thickness (with the exception of the edges of the side wings which are tapered for enhanced wearer comfort) and composition throughout, physical properties such as resilience and strength are reliably maintained throughout the wings at a sufficient level to benefit of a wearer. However, the degree to which resilience reduces with increasing distance from the toe box opening can be controlled by, for example, providing a tapered diminishing thickness of the side wings.
Optionally, the thermoplastic polymer material of the toe box is polypropylene.
Optionally, the Shore hardness of the polypropylene is 60A.
The Shore hardness of the thermoplastic elastomer (TPE) material forming the toe box liner will usually be less than that of the toe box itself. In one embodiment, a Shore hardness of the thermoplastic elastomer (TPE) material lies within the range of 40-50A.
Plastics and flexible resin materials disclosed in GB 2 449 821 are also considered suitable for use in the toe box portion disclosed herein.
According to a second aspect of the present invention, there is provided a shoe assembly comprising a foot support structure including:
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- a separable toe box and shank each provided with a series of cooperable connection members for facilitating their respective adjustable connection;
- a toe box opening being defined by a peripheral edge of the toe box; and
- a toe box liner lining the inner surface of the toe box;
wherein the toe box, the shank and the toe box liner are each moulded from a thermoplastic material; the toe box liner extending beyond the peripheral edge of the toe box opening at its opposing lateral sides to form foot-supporting side wings; and wherein the thermoplastic material of the toe box has a greater stiffness than that of both the toe box liner and the shank.
Optionally, an outsole is connected to the underside of the shank and toe box.
Optionally, the toe box is at least partially covered by an outer covering layer of an upper of the shoe assembly.
Optionally, an intermediate layer of thermoplastic polymer material is interposed between the toe box and an outer covering layer of the upper of the shoe assembly.
The Shore hardness of the thermoplastic polymer material forming the intermediate layer will usually be more than that of the toe box itself. In one embodiment, a Shore hardness of intermediate layer material is 70A.
Optionally, the intermediate layer of thermoplastic polymer material extends over substantially the entire vamp portion of the upper of the shoe assembly but does not extend to a boundary separating the vamp and quarter portions of the upper of the shoe assembly.
Optionally, the intermediate layer of thermoplastic polymer material does not overlap the ends of side wings which are most distant from the toe box.
Advantageously, the intermediate layer is formed from a relatively rigid thermoplastic polymer material so as to maintain the shape of the vamp portion of the shoe upper during insertion and removal of the toe box. However, since the intermediate layer is arranged so as not to overlap any, or at least not all, of the side wings at lateral sides of the shoe upper then flexibility of the shoe at this region is not compromised. The strategic absence of the intermediate layer at this location—i.e. at the rear part of the vamp where it meets the shoe's quarter (the boundaries of which are illustrated in
Optionally, a strip of fibre reinforced polymer extends transversely across the vamp of the shoe assembly.
Optionally, the opposite ends of the strip of fibre reinforced polymer are attached to an outsole and/or an inner liner layer of the upper of the shoe assembly.
It will be appreciated that the inner liner layer—which may be a cotton material—is separate from the toe box liner. In particular, the inner liner layer lines the remaining parts of the shoe rearward of the toe box and the toe box liner.
Optionally, the strip of fibre reinforced polymer is connected to the outsole at positions behind the foremost extent of a throat line of the shoe defined by a foot-receiving opening in an outer covering layer.
Optionally, the strip of fibre reinforced polymer extends over each side wing.
In one embodiment, there is no physical attachment between the strip of fibre reinforced polymer and each side wing.
Optionally, the strip of fibre reinforced polymer extends across the vamp of the shoe assembly in a generally curved or sinusoidal path.
Optionally, the strip of fibre reinforced polymer is adapted to be widest at its most lateral positions on the vamp and narrowest at its central uppermost position on the vamp.
Advantageously, the shape of the strip of fibre reinforced polymer and its narrowing central uppermost position on the vamp proximate the toe box provides a greater amount of support at the lateral parts of the shoe whilst minimising forces imparted to a dancer's foot at the instep. The positioning of the strip of fibre reinforced polymer and its manner of connection within a shoe structure ensures that it provides effective support to the metatarsals whilst remaining aesthetically pleasing by being substantially invisible from the exterior of the shoe.
The separable toe box, shank and cooperable connection elements disclosed in GB 2 449 821 are also considered suitable for use in the shoe assembly of the present invention.
It will be appreciated that references herein to a shoe includes all shoes but particularly those which are used for dance or performing arts. In one embodiment the shoe is a ballet shoe. For ease of disclosure, all references hereinafter relate to a ballet shoe without the intention of limiting the disclosure in that sense.
The improved shoe will now be described, by way of example only, with reference to the accompanying drawings in which:
Referring first to
The toe box 3 portion may be moulded from a thermoplastic polymeric material having greater rigidity than the shank portion 2. In one embodiment, the thermoplastic material has a softening point of between roughly 49° C. (120° F.) and 104° C. (220° F.). Further, the polymer may be selected from the following: an ionomer resin, an ethylene-vinyl acetate copolymer, a styrene-ethylene-butylene-styrene (SEBS) block copolymer, acrylonitrile butadiene styrene (ABS), polycarbonate (PC), polypropylene (PP) and a polyurethane (e.g. thermoplastic polyurethane (TPU)). In a further embodiment, the toe box portion may be constructed from a nylon material (e.g. nylon-6, -11 or -12).
The shock absorbing portion 6 may be constructed from an open celled polyurethane foam or gel like substance. The shock absorbing portion 6 has the advantage of providing quiet contact between the shoe and the floor so that a ballet dancer can achieve graceful movement.
In a further embodiment, the toe moulding portion is constructed from a heat responsive thermoplastic elastomer, for example, the viscosity of the elastomer increases with application of heat. In a yet further embodiment, the toe moulding portion is constructed from a styrene-ethylene-butylene-styrene (SEBS) block copolymer (e.g. SEBS 25 C). This embodiment has the advantage of allowing the toe moulding portion to be easily moulded to the ballet dancer's foot. For example, moulding may occur by simple application of heat from an external source.
In some embodiments all surfaces of the shoe which are in contact with a user's foot are lined with a soft, resilient coating selected from a foam comprising a polyurethane, a cross-linked polyethylene, a polyvinylchloride and nitrile rubber blend or an ethylene vinyl acetate (EVA) copolymer. In a yet further embodiment, the surface of the shank portion in contact with the user's foot is lined with a soft, resilient coating. In a yet further embodiment, the soft, resilient coating is an ethylene vinyl acetate (EVA) copolymer. In a yet further embodiment, the soft resilient coating additionally comprises odour controlling means. In this embodiment, the odour controlling means may be incorporated within the outer covering (e.g. by application of odour controlling agents) or the odour controlling means may be separately applied to the surface of the shank portion in contact with the user's foot (e.g. by the presence of a detachable insole) by any of the attachment means mentioned herein. In one embodiment, the odour controlling means comprise a separate insole separately attached to the surface of the shank portion in contact with the user's foot by way of a releasable or permanent attachment, e.g. Velcro™, an adhesive (either permanent or temporary) or any other means of attachment.
The shank portion 2 comprises a protruding male component 7 on the end distal to the heel, which is engageable with a female cavity component 8 on the base of the toe moulding portion 5 of the toe box portion 3. Both the shank portion 2 and the toe box portion 3 are constructed from a thermoplastic polymeric material such that the shank portion 2 has a lower softening point than the toe box portion. The shock absorbing portion 6 is constructed from an open celled polyurethane foam. The shank portion 2 has a soft, resilient coating of foam (not shown) on the upper surface which is in contact with the user's foot which additionally comprises odour control agents.
In use, a ballet dancer will connect the shank portion 2 to the toe box portion 3 which results in an assembled shoe.
It is intended that the shank portion 2, toe box portion 3 and detachable outer covering will comprise separate items of commerce which may be purchased by a ballet dancer or their employer separately. Therefore, once any part of the shoe has been worn out then it may simply be replaced without the need for entire replacement of the shoe.
The toe box liner 64 provides protection to a dancer's foot from the relatively stiffer outer shell of the toe box 60 whilst ensuring sufficient support, particularly to the metatarsal region of the foot. The toe box liner 64 extends approximately 10 mm beyond the upper peripheral edge of the toe box 60 so as to lie proximate the upper central throat region 66 of a shoe's vamp. This protects the upper metatarsal region of a dancer's foot from directly impacting against the relatively more rigid edge of the toe box 60.
Side wings 68 of the toe box liner 64 extend significantly further beyond the peripheral edge of the toe box 60 at its opposing lateral sides. In one embodiment, a side wing 68 extends rearwardly away from each lateral side of the toe box 60 by a distance of approximately 40-45 mm. The side wings 68 lie opposite each other in a mutually parallel arrangement and gradually diminish in height with increasing distance from the toe box 60.
The side wings 68 are formed from a continuation of the same unitary piece of thermoplastic elastomer (TPE) material forming the toe box liner 64. The characteristics of this material were selected so as to balance the required degree of flexibility with sufficient levels of stiffness to offer both comfort and support to a dancer's foot in use, especially when balancing “en pointe”.
The metatarsal support layer 70 tracks a generally sinusoidal path between the opposite lateral positions 72 of the vamp. When viewed from above (see
Although not shown in the drawings, the shoe of
The selection of a fibreglass material for the metatarsal support layer 70 balances the need for a lightweight yet incredibly strong material whilst avoiding brittleness associated with alternative materials such as carbon fibre. An appropriate thickness of the fibreglass material which ensures a sufficient degree of flexibility is 0.25 mm.
Crucially, the rearward extent of the intermediate layer 80 is spaced from the boundary between the forward vamp portion of the shoe's upper and its hind quarter portion. In a non-limiting example, the spacing is 30 mm. Usually, this boundary will be evident as a physical join of two parts of the shoe upper and in the illustrated embodiment it is defined by a vertical line of stitching 82. By limiting the rearward extent of the intermediate layer 80 in this way the rearmost ends of the toe box's side wings 68 are not overlapped. The strategic absence of the intermediate layer at this location results in a zone of enhanced flexibility permitting more freedom of movement for the foot during certain dance movements. Importantly, this is achieved without noticeably compromising the overall stability of the foot, or adversely affecting the distribution of forces within the shoe.
The features of the present invention help to address the conflicting design requirements of a dance shoe. In particular, the side wings 68 provide consistent levels of stiffness and support for a dancer when “en pointe” whilst, on the other hand, the articulated co-operable members for connecting the toe box and shank maintain sufficient malleability during the transition between the shoe and foot being in a flat or horizontal position and a full extended “en pointe” position.
En pointe support is significantly enhanced by the addition of the metatarsal support layer 70 that extends across the metatarsal nodal region of the foot which bears the majority of a dancer's body weight when “en pointe”. The high strength and rigidity of the metatarsal support layer 70 means that its thickness can be minimised without compromising on the level of support provided thus reducing or eliminating any adverse aesthetic impact noticeable at the outer cover layer of the shoe. The sinusoidal path traced by the metatarsal support layer 70 accommodates the likely positions of the metatarsal bones on the dancer's feet. The intermediate layer 80 also contributes to enhanced support.
Modifications and improvements may be made to the foregoing without departing from the scope of the invention as defined by the accompanying claims. For example, in some embodiments, the toe box portion and the side wings may be made of differing materials which are assembled or bonded together to provide a region of higher rigidity than the remainder of the toe box portion.
Claims
1. A foot support structure for a shoe comprising:
- a toe box;
- a connection member facilitating adjustable connection of the toe box to a cooperable connection member on a separate shank portion of a shoe;
- an opening defined by a peripheral edge of the toe box portion; and
- a toe box liner lining the inner surface of the toe box portion;
- wherein the toe box and toe box liner are each moulded from a thermoplastic polymer material and the toe box liner extends beyond the peripheral edge of the toe box at its opposing lateral sides to form foot-supporting side wings; and wherein the thermoplastic polymer material of the toe box has a greater stiffness than that of the toe box liner.
2. A foot support structure according to claim 1, wherein each side wing extends rearwardly away from each lateral side of the toe box by distance lying in the range of 20 mm to 60 mm.
3. A foot support structure according to claim 1, wherein the height of each side wing relative to the toe box diminishes with increasing distance from the toe box opening.
4. A foot support structure according to claim 1, wherein the thickness of the toe box liner lies in the range of 2.0 mm to 3.0 mm.
5. A foot support structure according to claim 1, wherein the thickness of each side wing diminishes with increasing distance from the toe box opening.
6. A foot support structure according to claim 1, wherein each side wing is formed from a continuation of a unitary piece of thermoplastic elastomer (TPE) material forming the toe box liner.
7. A foot support structure according to claim 1, wherein the thermoplastic polymer material of the toe box is polypropylene.
8. A foot support structure according to claim 1, wherein the Shore hardness of the polypropylene is 60A.
9. A shoe assembly comprising a foot support structure including:
- a separable toe box and shank each provided with a series of cooperable connection members for facilitating their respective adjustable connection;
- a toe box opening being defined by a peripheral edge of the toe box; and
- a toe box liner lining the inner surface of the toe box;
- wherein the toe box, the shank and the toe box liner are each moulded from a thermoplastic material; the toe box liner extending beyond the peripheral edge of the toe box opening at its opposing lateral sides to form foot-supporting side wings; and wherein the thermoplastic material of the toe box has a greater stiffness than that of both the toe box liner and the shank.
10. A shoe assembly according to claim 9, wherein an outsole is connected to the underside of the shank and toe box.
11. A shoe assembly according to claim 9, wherein toe box is at least partially covered by an outer covering layer of an upper of the shoe assembly.
12. A shoe assembly according to claim 9, wherein an intermediate layer of thermoplastic polymer material is interposed between the toe box and an outer covering layer of an upper of the shoe assembly.
13. A shoe assembly according to claim 12, wherein the intermediate layer of thermoplastic polymer material extends over substantially the entire vamp portion of the upper of the shoe assembly but does not extend to a boundary separating the vamp and quarter portions of the upper of the shoe assembly.
14. A shoe assembly according to claim 12, wherein the intermediate layer of thermoplastic polymer material does not overlap the ends of side wings which are most distant from the toe box.
15. A shoe assembly according to claim 9, wherein a strip of fibre reinforced polymer extends transversely across the vamp of the shoe assembly.
16. A shoe assembly according to claim 15, wherein the opposite ends of the strip of fibre reinforced polymer are attached to an outsole and/or an inner liner layer of the upper of the shoe assembly.
17. A shoe assembly according to claim 16, wherein the strip of fibre reinforced polymer is connected to the outsole at positions behind the foremost extent of a throat line of the shoe defined by a foot-receiving opening in an outer covering layer.
18. A shoe assembly according to claim 15, wherein the strip of fibre reinforced polymer extends over each side wing.
19. A shoe assembly according to claim 15, wherein the strip of fibre reinforced polymer extends across the vamp of the shoe assembly in a generally curved or sinusoidal path.
20. A shoe assembly according to claim 15, wherein the strip of fibre reinforced polymer is adapted to be widest at its most lateral positions on the vamp and narrowest at its central uppermost position on the vamp.
Type: Application
Filed: Jun 30, 2014
Publication Date: Jan 8, 2015
Inventor: Richard Swift (Lancashire)
Application Number: 14/319,109
International Classification: A43B 7/14 (20060101); A43B 5/12 (20060101);