PLATFORM SHOE, LAST AND INSOLE THEREFOR AND MANUFACTURE THEREOF

An insole for a high heeled platform shoe (30), shaped to accommodate a platform (48) between the insole and an underside of a wearer's foot. Also, a high heeled platform shoe (30) including an outsole, an insole and a platform, in which the outsole is located on one side of the insole and the platform is located on the other side of the insole. Also, a last for lasting a high heeled platform shoe, the last being shaped to correspond to the shape of a foot and a platform located against the sole of the foot. Manufacture includes providing a platform located on one side of an insole and an outsole on the other side of the insole. The platform and its location above the insole provide comfort to the wearer of the shoe and reduce health problems.

FIELD OF THE INVENTION

The invention relates to a platform shoe or footwear, in particular a high heeled platform shoe. The invention also relates to a last, an insole and a method of manufacturing a platform shoe.

BACKGROUND TO THE INVENTION

High heeled shoes are typically worn to make a wearer appear taller. Various health problems may be caused by wearing high heeled shoes. High heeled shoes slant the foot forward and down while bending the toes up. The more that the feet are forced into this position, the more the Achilles tendon may shorten. This may then cause problems when the wearer chooses lower heels or flat-soled shoes. Also, when the foot slants forward, a much greater weight is transferred to the ball of the foot and the toes, increasing the likelihood of damage to the underlying soft tissue that supports the foot. Further, in many shoes, style dictates function, such that toes compress or are forced together, possibly resulting in blisters, corns, hammer toes, bunions (hallux valgus), Morton's neuroma, plantar fasciitis and many other medical conditions, most of which are permanent and may necessitate surgery. Furthermore, high heels, because they tip the foot forward, put pressure on the lower back by making the rump push outwards, crushing the lower back vertebrae and contracting the muscles of the lower back. It is therefore desirable to reduce the degree to which the foot slants forward.

Known platform shoes raise a fore part of a wearer's foot so that the difference in heights of the fore part and a heel of the foot is less than if the fore part was not raised. Alternatively or additionally, raising the fore part of the foot facilitates further raising of the heel. Such platform shoes include midsoles made from plastic. Shoes made with such midsoles are typically uncomfortable to wear.

A known document, WO2009/109833, discloses a platform shoe having a forefoot portion for supporting and covering a fore part of a wearer's foot. The forefoot portion is such that the fore part of the foot is raised from the ground. Referring toFIG. 1, the shoe10has a shoe upper12and a sole14. The shoe10is shown on a last16on which the shoe is formed. The sole14is made of multiple layers, namely an insole18, a spacer piece termed a “midsole”20which serves to elevate the wearer's foot, and an outsole22. The insole18forms the interior bottom of the shoe and sits beneath the wearer's foot. An insole foam layer24is located between the insole18and the midsole20. Another layer in the form of an upper lining26is located on the insole18to form a contact surface with the underside of the wearer's foot. Outsole22directly contacts ground. The midsole20is located between the insole18and the outsole22. The shoe upper12is fastened to the outsole22and the midsole20to partially enclose the wearer's foot. A certain amount of rigidity is required in the insole18and the outsole22in order for the shoe to retain its shape when walking. Typically, the insole18is made of a hard material and includes a metal shank. There is typically little material, if any, between the underside of the wearer's foot and the insole18. It is well known that high-heeled shoes are uncomfortable for the wearer.

It is an object of the present invention to improve the comfortableness of such shoes and to prevent or reduce health problems associated with such shoes.

SUMMARY OF THE INVENTION

According to the present invention, there is provided a platform shoe wherein the platform is located above the insole. Thus, an outsole may be located on one side of the insole and the platform located on the other side of the insole. According to another aspect of the present invention, there is provided a platform shoe including an outsole, an insole and a platform, wherein the outsole is located on one side of the insole and the platform is located on the other side of the insole.

As the platform is placed above the insole, the platform is closer to the wearer's foot. This addresses some of the issues mentioned above. This may benefit the wearer by countering some of the potential detrimental effects of wearing high heels, some of which are mentioned in the following:They may cause foot pain.They increase likelihood of sprains and fractures.They may create foot deformities, including hammertoes and bunions.They may cause an unsteady gait.They may shorten the wearer's stride.They may render the wearer unable to run.Altered forces at a wearer's knee caused by walking in high heels may predispose the wearer to degenerative changes in the knee joint.They may cause foot and tendon problems.Women who wear high heels frequently have a higher incidence of degenerative joint disease of the knees. This is because the high heels cause a decrease in the normal rotation of the foot, which puts more rotation stress on the knee.

In addition, the extra height provided at the fore part of the shoe allows the heel of the shoe to be of greater height without increasing the angle of the shoe and without increasing pressure on the fore portion of the wearer's foot.

Preferably, the platform is resiliently compressible for shock absorption. This further aids in preventing some of the potentially detrimental effects of wearing high heels.

The platform shoe may include a sock, in which case the platform is located below the sock. The sock is of a material deformable to match the contours of the underside of a wearer's foot. This provides comfort to the wearer. The platform may be located between the insole and a sock.

The platform may be formed of a synthetic material such as poly-urethane or non-synthetic (natural) material such as natural cork. The platform may be selected from several possible platforms in accordance with characteristics and/or wishes of the wearer, such as the height and weight of the wearer etc. Different platforms for different shoes/wearers may be of different size, volume, depth, width and density. Attributes of the platform may then be incorporated into the overall design of the shoe. For example, the depth of the platform will alter the size of the upper required.

The platform and the sock may be formed of a single piece. This piece may be of a single or multiple materials.

The platform shoe described above may be a high heeled platform shoe. Such a platform shoe may further comprise a heel portion, arranged such that a bottom of a heel of a wearer's foot is raised higher than a bottom of a fore part of the foot.

The platform may be made of multiple layers of material. Thus different layers of material may have different properties of rigidity, cushioning and density. The platform may be selected from several platforms, each having layers of material of different rigidities, cushioning and density properties in accordance with a known physical parameters of the wearer, such as weight and height.

The platform may comprise of different regions for abutting against different parts of the foot and which have different rigidity and cushioning properties. For example, the regions against which the heel and a fore part of the wearer's foot abut may be made of softer material than other regions of the platform.

The insole may include a shank for supporting the weight of a wearer, wherein the shank is shaped to accommodate the platform. The insole may alternatively be made of a single piece of material not incorporating a shank. In this case the material of the insole is strong enough to prevent need for the shank. This can be a single piece of steel or aluminium or hardened plastic.

The platform may fit flush against at least a fore part of the insole. The platform may not extend over a rear part of the insole.

Alternatively, the platform may extend over the rear part of the insole. The platform may be thinner at the rear part of the shoe than at the fore. Alternatively, the platform may be of approximately uniform thickness.

According to a further aspect of the present invention, there is provided a method of manufacturing an insole for a platform shoe, comprising forming an insole shaped to accommodate a platform between the insole and the underside of a wearer's foot.

There is further provided a method of manufacturing a platform shoe comprising the method of manufacturing an insole described above.

According to another aspect of the present invention, there is yet further provided a method of manufacturing a platform shoe, including locating the platform above the insole. This may be such that the platform is on one side of the insole and an outsole is on the other side of the insole.

The method may further comprise attaching the platform to the insole, lasting the insole, the platform and an upper, and attaching the outsole to the insole and upper. Alternatively, the method may further comprise lasting the insole and an upper, then inserting the platform, and attaching the outsole to the insole and upper before or after inserting the platform.

The method may further comprise a step of affixing a heel portion to the insole, before or after lasting. The method may also comprise a prior step of forming a last for lasting the shoe. Alternatively, the heel portion and the outsole may be formed of a single piece and attached at the same time.

The method may further comprise locating a sock so that when the shoe is worn the sock is between the platform and the wearer's foot. The method may further comprise lasting an upper between the insole and the outsole.

According to another aspect of the present invention, there is provided a last (secondary last) for lasting a platform shoe, shaped to correspond to the shape of a foot or a primary last and a platform located against the sole of the foot. According to a yet other aspect of the present invention, there is provided a last (secondary last) for lasting a platform shoe, shaped to correspond to the shape of a foot, a sock located against the sole of the foot and a platform for locating between an insole and the sock. There may be provided an insole formed against such a last.

According to another aspect of the present invention, there is provided a method of forming a (secondary) last, comprising moulding a (secondary) last to correspond to the shape of another (primary) last and (at least) a platform.

According to another aspect of the present invention, there is provided an insole for a platform shoe, shaped to accommodate at least a platform between the insole and an underside of a wearer's foot. The insole may be further shaped to accommodate a sock between the insole and an underside of a wearer's foot. The insole may be formed of sufficiently strong material that a shank is not required.

According to yet another aspect of the present invention, there is provided a support for a platform shoe, the support extending at least partially around the periphery thereof for impeding sagging or contracting of an upper. The support may extend between the insole and the platform.

There may be provided an assembly comprising a platform for a platform shoe and an aforementioned support.

The platform may include a recessed portion therein extending at least partially around the platform, and at least part of the support fits in said recess.

There may also be provided a part for a platform shoe, comprising an insole for a platform shoe, wherein the insole and the aforementioned support are attached or integrally formed.

In any of the above described aspects, the platform may be at least 1 cm, or at least 2 cm, or at least 3 cm, or at least 4 cm, or at least 5 cm or at least 6 cm in thickness. In any of the above described aspects, the platform shoe may be a high heeled platform shoe. In such case in use of the shoe the height of a wearer's heel from the ground may be at least 2 cm. Such height would not normally be above 20 cm. The height may be at least 5 cm, at least 7 cm, or at least 10 cm from the ground.

DETAILED DESCRIPTION OF EMBODIMENTS

Like parts are denoted by like reference numerals throughout.

Certain terminology will be used in the following description for convenience and reference only, and should not be deemed limiting. For example, a shoe has a conventional orientation and the words “fore”, “rear”, “above” and “below” are to be construed in view of that orientation. Similarly, a foot has a conventional orientation and the words “fore” and “underside” are to be construed in view of that orientation.

The term “platform” is used to refer to an element whose function will be apparent from the following description. The term “spacer” or “spacer element” may alternatively be used.

The platform shoe30shown inFIG. 2comprises a rear portion32, a midfoot portion34and a forefoot portion36each respectively over a longitudinal section of the shoe. The sections are indicated at A, B and C inFIG. 3. The rear portion32of the shoe fits around the heel of a wearer's foot38, below the calcaneus bone, and also such as to elevate the heel of the wearer's foot38from the ground40. The midfoot portion34fits around the arch of the foot38, formed by the tarsal bones. The forefoot portion36of the shoe30fits around the fore part of the foot38, including the toes and metatarsals. In addition to the rear portion32raising the heel of the wearer's foot38from the ground40, the fore part of the foot38is raised from the ground40by a platform48in at least the forefoot portion of the shoe, as will be described in detail in the following. In this embodiment, the rear portion32raises the heel of the foot38higher than the forefoot portion36raises the fore part of the foot38.

As shown inFIG. 3, the shoe30comprises a sole, an upper42and a heel44. InFIG. 3, these parts are shown on a last43. The sole is formed of multiple layers, namely an insole46, the platform48and an outsole50.

The upper42helps to hold the shoe30onto the foot38. The upper42may be made of leather or another suitable material. The heel44is typically formed of a high density plastics material and includes an abrasion resistance base piece45(known as the “top piece” in the art) for impacting against the ground40. The heel44supports the heel of the wearer's foot.

The insole46attaches to a lasting margin42aof the upper42. The insole46is disposed between the outsole50and the platform48. Thus the outsole50is located on one side of the insole46and the platform48is located on the other side of the insole46. The insole46may be made from cellulosic paper board, such as strong cardboard, or synthetic non-woven insole board, but may be made of another material. Since the platform48is located above the insole46, the insole46may in embodiments be formed of a harder material than is conventional without causing discomfort to the wearer, for example aluminium.

The outsole50forms the exterior bottom of the shoe30, and is for repeated contact with the ground. The outsole50may be made of leather or hard rubber (natural rubber or synthetic such as polyurethane), although other materials are suitable. The outsole may comprise a single piece, or may be an assembly of separate pieces of different materials. It has fore, central and heel portions thereof respectively in the forefoot, midfoot and rear portions36,34,32of the shoe30. A surface of the fore portion of the outsole50directly contacts the ground40. The outsole50arches in its central portion from its fore portion to the rear portion32of the shoe30. The part of the outsole50in the rear portion extends downwardly from the central portion to the ground40or near to the ground40down a front facing side of the heel portion32. The base piece45may be considered as a part of the outsole50.

A purpose of the platform48is as a spacing element for raising the bottom of the fore part of the foot38from the ground40to make the wearer appear taller. The platform48is located between the insole46and the wearer's foot. The platform48is preferably made of synthesised material. The material may be a foamed material such as a shape retentive, flexible polymer. The material may be polyurethane. In embodiments, the platform48may provide a cushioning structure that is comfortable against the underside of the foot. The material of the platform48does not however compress substantially and so does not affect lateral movement of the foot, nor does the material depress significantly to render the shoe unstable. A suitable material is an injection moulded foam such as ethylene vinyl acetate (EVA). EVA is a polymer that approaches elastomeric materials in softness and flexibility, yet can be processed like other thermoplastics. EVA has little or no odour. Other suitable foam polymers or rubber mixed with compounds may be used to form the platform48, for example polyurethane, thermoplastic rubber, and nitrol polyvinyl.

The platform is preferably at least 0.3 cm in thickness. More preferably, the platform is at least 1 cm in thickness, or at least 1.5 cm in thickness. More preferably still, the platform48may be at least 2 cm, or more preferably at least 3 cm, or at least 4 cm or at least 5 cm in thickness. It is noted that herein the disclosure of alternative values for the lower limit of a parameter, coupled with an indication that one of said values is more highly preferred than the other, is to be construed as an implied statement that each intermediate value of said parameter, lying between the more preferred and the less preferred of said alternatives, is itself preferred to said less preferred value and also to each value lying between said less preferred value and said intermediate value.

In embodiments, the upper surface of the platform48and a rear part of an upper surface of the inner sole46are shaped to approximately conform to the shape of the underside of a wearer's foot, and the shape and width are such as to approximately minor the shape of the overlying region of the wearer's foot. The platform48includes a peripheral portion of material extending around longitudinal sides and front which has a greater thickness than more centrally located material of the platform48, in order to conform to the shape of the foot.

The rear portion32raises the heel of the foot38such that the bottom of the heel is a distance indicated at X from the ground40when the shoe30is located on the ground40. This distance may be from 2 cm to 20 cm. Preferably, the bottom of the heel is at least 3.5 cm from the ground.

The forefoot portion36raises the fore part of the foot38such that the bottom of the fore part is a distance indicated at Y from the ground40. This distance may be at least 1 cm. The shoe raises the bottom of the heel of the wearer a distance X-Y from the bottom of the fore part of the foot38. Generally, the greater the distance X, the greater the distance Y can be. The greater the distance X-Y, the more pressure will be put on the fore of the wearer's foot. Also, for smaller shoe sizes, distance Y should be reduced, preferably proportionally. The distance X-Y is preferably at least 1 cm, more preferably still at least 2 cm.

The shoe30also includes a sock52, which sits on the platform48between the platform48and a bottom of a foot. The sock may be adhered to the platform48by an adhesive or other attachment means. The sock52and the platform48may be provided as a single piece. The sock52may comprise the platform48. The sock may be made of memory foam.

Referring toFIG. 4, the insole46has a shank54affixed on an underside thereof. The shank is typically a metal strip running from the heel portion to the fore part of the shoe, to act as a support bridge to take the wearer's weight. The underside is shown in the Figure. The insole50and the shank54are shaped to accommodate the platform48on an upper side thereof The shank54is fixed to the insole46, by rivets46ain the present case, although other kinds of fixing means may be used.

Since the insole46is spaced from the foot by the platform48, it may be made of a highly rigid material without compromising comfort. For example, the insole may be made of metal. In this case a shank54is not required. Also, where a shank is provided, the shank could alternatively be affixed to the upper side of the insole.

It has been mentioned that the insole46and the platform48may be shaped to conform to the shape of the underside of the foot. However, it is not essential for them to be shaped to conform to the contours of the foot. The platform48, as well as the insole46, may be made out of rigid material, preferably a material which also absorbs shock. The sock may be shaped to conform the contours of the underside of the wearer's foot. The sock may be formed of a deformable material, for example a memory foam or another suitable material.

In embodiments, the shank54is not required. Advantageously, the insole is instead formed of a sufficiently strong, rigid material that it is capable of supporting the wearer's weight. For example, the insole may be made from aluminium. The insole46and the platform46may be formed of a single piece.

Referring toFIG. 5, the platform shoe30can be made according to the processes described in the following. Conventionally, shoes are built around a last that resembles the shape of a foot. A different last is typically required for manufacture of shoes for right and left feet. Lasts are typically moulded from high-density plastic, although other materials are suitable. The shape of the last may be designed using dedicated design software. The resulting shape of the shoe depends on the shape of the last, and may also depend on the lasting process used and the material from which the shoe is made. A conventional last around which the shoe is formed is referred to in the following as a “primary last”.

In one process, the insole46is formed or preformed separately to the rest of the shoe. Apparatus for forming the insole46comprises a mould piece or specially adapted last (“secondary last”) having a pressing surface substantially matching the shape of a wearer's foot and the platform48when against the wearer's foot. The secondary last has a larger forefoot section than the primary last.

The secondary last may be created from an assembly of the primary last and the platform or a shape corresponding to the shape of the platform. Thus, the primary last is created, the platform is created from the primary last and then the secondary last is created from the primary last and the platform or corresponding shape. The mould piece or secondary last may also be shaped to allow for the thickness of the sock. However it should be understood that the making of a secondary last does not require the existence of a primary last.

The mould piece or secondary last presses against a template insole to form the insole46. Alternatively, the insole46may be otherwise formed, particularly where the material of the insole46is unsuitable for manufacture by pressing.

Thus, as indicated at step A inFIG. 5, an insole is formed using the secondary last such that when the platform38is affixed, the upper surface of the consequent assembly approximately corresponds to the underside of a foot. The platform48is then fixed to the insole46at step B, for example by adhering.

In step C, the insole46and the upper42are lasted, with the platform48attached to the insole46, using a primary last to form a shoe enclosure, such that the platform48is on one side of the insole46, and the platform48is located adjacent the primary last. The upper42is thus cemented at its margin to the edges of the insole46to create the foot enclosure.

In step D, the heel portion is then attached to the insole46, for example by a screw arrangement, and the outsole50is adhered to the upper42, the insole46and the heel portion. In an alternative to cementing, the upper42can be stitched to the insole and/or other layers.

Any one or more of steps A to D may be carried out by hand or an appropriately configured lasting machine.

The sock can be adhered or otherwise attached to the platform48after step D. Alternatively, the sock can be adhered or otherwise attached to the platform48before step A.

After a step including adhering/cementing, the adhered/cemented parts may be left to dry or partially dry, for example for 10-15 minutes. Subsequently the adhered components may be heated to activate the adhesive, and combined in a pressure machine to apply force/weight to the glued components. During this process, the materials of the soles are under stress. The process requires the platform48to be formed of a material that is hard enough to maintain its shape to avoid distortion of the platform48while the shoe is lasted. The shoe may be lasted for up to36hours.

In an alternative process, the insole46may be formed from a template against an assembly comprising the primary last with which the shoe will later be lasted, and a block of the shape of the platform that is attached to the last, such that the insole is formed to have a shape such that when the platform is put against it, the shape of the consequent assembly will be approximately the shape of the underside of a wearer's foot. In an alternative, the block may be absent and instead, conveniently, the actual platform48may be attached to the underside of the primary last and then the insole46shaped from a template to conform to the shape of the platform48and the primary last. This requires the platform48to be formed of a material hard and strong enough for shaping of the insole46against it. In this process, a secondary last is not required.

In a variant process, the shoe30can be lasted without the platform48and the sock using the secondary last. The platform48can instead be inserted and adhered to the insole46after lasting. In this case, the sock can also be adhered or otherwise affixed to the platform48before or after the platform48is inserted. In this case, the platform48does not have to tolerate pressure or heat treatment that may be involved in lasting, and also a primary last is not necessarily required.

It will be appreciated that for different heights of heel and different sizes of shoe, different primary and secondary lasts will be required. For example, the shoe30might be produced with heels of four different heights. In this case, different shaped soles will be required necessitating a particular primary last for each height for each size of shoe. Also, different secondary lasts may be required for the lasting process.

Also, the shape of the last (primary or secondary, depending on the particular process used) depends on the desired shape of the region enclosing the wearer's toes. Other characteristics of the shoe that have to be selected are the platform material, the dimensions of the platform, a sock pattern, and an upper material and pattern.

In a variant process, a mould is provided shaped to form the platform, and the insole may be formed separately and located in the mould. The platform is then formed by injection moulding into the mould and bonds to the insole in the moulding process. The shoe is then lasted using the integrated platform and insole using an appropriately shaped last.

Generally, shoes in accordance with embodiments can be hand-made or bulk manufactured by machine.

In another embodiment, the platform shoe may be modified to include a support located between the platform and the insole. The purpose of the support is to provide rigidity to impede sagging or contracting of the upper after lasting, since the platform alone may not provide sufficient rigidity for this purpose. In particular, leather, stretched during lasting, may attempt to return towards its original shape and the purpose of the support is to impede this.

FIG. 6shows a platform48aand support56having a lip58. The lip58extends around the periphery of the platform. The platform48aand the support56are shaped to take the place of the platform48shown inFIG. 3. Thus, the support56extends over the insole between the insole and the platform48a.Thus in this case the support is in the form of a tray and the platform is shaped to accommodate the support56. The tray can be formed of a single piece of hardened plastic, or another material.

The support may be in the form of a frame, such that it extends around the periphery of the platform without material extending over the whole of the insole between the insole and the platform.

The support may reduce the tendency of the upper to sag or contract, irrespective of whether the shoe is lasted with the platform in or if the platform is inserted afterwards. In particular, where the upper is attached to the insole and the platform is formed of flexible material, the support may impede sagging or contracting of the upper during lasting or finished of the shoe. The support provides structural rigidity to the shoe, where the flexibility of the platform might result in creasing or sagging of the upper. The support may be fixed to the insole, for example by an adhesive. The support and the insole may be formed of a single piece.

Various modifications can be made to the embodiments described above. The insole46and outsole50can be integrally formed. Any one or more of the platform48, the insole46and the outsole50can each be formed of more than one piece. The multiple pieces may be in the form of layers.

The heel and the insole may be formed of a single piece.

In a modification, the platform does not extends to the heel portion of the shoe. The underside of a wearer's foot thus rests against the platform from the forefoot to the heel, which improves comfort against the heel. A sock may be located between the platform and the underside of the foot.

A platform shoe may also include a midsole or spacer between the insole and the outsole. The midsole or spacer may provide additional height to the wearer. The midsole or spacer may absorb shock when the shoe is in use.

It should be understood that, while embodiments are described in a high heeled shoe, embodiments of the invention can be implemented as a flat platform shoe or a boot or any kind of shoe with a heel in which the fore foot is raised. Embodiments of the invention are suitable for shoes intended for men as well as for women.

Key toFIGS. 2 to 4and630—platform shoe32—rear portion of platform shoe34—midfoot portion of platform shoe36—forefoot portion of platform shoe38—foot40—ground42—upper42a—lasting margin43—last44—heel45—top piece46—insole46a—rivets48,48a—platform50—outsole52—sock54—shank56—support58—lip