HK1109031B - Device for high-heeled shoes and method of constructing a high-heeled shoe - Google Patents

Description

Apparatus for high-heeled shoes and method of constructing high-heeled shoes

Technical Field

The present invention relates to a shoe that is easy to construct and provides greater comfort to the wearer without affecting the fit or style of the shoe. The invention is particularly suitable for high-heeled shoes.

Background

Conventional high-heeled shoes have a reputation of being very uncomfortable. There is survey information showing that up to 20% of users of such shoes experience foot pain directly associated with the shoe, and most users experience such pain after as little as four hours of use.

In order to understand the prior art and the present invention, the anatomy of the foot and the foundation of the shoe construction must be understood. To this end, FIG. 1 is a schematic view of the bones of the foot and those portions of the shoe that underlie the sole of the foot. Referring to fig. 1, the anatomy of the foot and the basis of shoe construction are briefly described below.

Fig. 1 is a schematic medial side view of the bones of a human foot 10. For the purposes of this application, reference to rearward means in the rearward direction of the foot or heel 20; reference to forward means in the direction of the front face 30 of the foot where the toes or phalanges 31 are located; references to medial mean that the side of the foot where the arch 40 is located; lateral involvement means the lateral side of the foot; and references to upper or top and lower, bottom or underside assume that the foot or shoe is positioned in an upright position.

The heel 20 (also known as the ankle bone) includes an ankle bone 21 and a calcaneus bone 22. The posterior inferior surface of the calcaneus 22 has a small bulge 23 known as the calcaneal tuberosity. The bones of the foot also include the navicular 41, cuneiform 42, metatarsals 45 and phalanges or toes, the big toe 31 being visible in fig. 1. The metatarsal heads 46 are located at the forward ends of the metatarsal shafts 47. The metatarsal bones are labeled 1 to 5, and 1 denotes the big toe.

Also depicted in fig. 1 is a partially exploded view of those portions of a conventional high-heeled shoe 50 that underlie the sole of the foot. The shoe 50 has a heel 51 generally attached to the lower surface of a sole 52 of the shoe 50, and the sole 52 in turn supports an insole 53, on which insole 53 a pad 54 is placed. In conventional footwear, the insole is typically of a relatively stiff construction from the area under the wearer's heel to the metatarsal heads. The liner is generally very flexible and is usually very thin, typically no more than 0.5 mm thick. The sole of the foot typically rests on the pad.

According to conventional shoe construction methods, a last is a form around which a shoe is constructed. During manufacture, the lower surface of the last rests on the upper surface of the insole board, and then an upper is formed around the last and attached to the insole board. Optimally, the lower surface of the last and the upper surface of the insole board fit smoothly to properly manufacture the shoe. If the lower surface of the last or the upper surface of the insole board has any convex shape, then a corresponding concave shape must be provided in the insole board or last, respectively. To ensure a satisfactory shoe construction, any such convexity and corresponding concavity must be carefully aligned during shoe manufacture, thereby introducing additional complexity and/or quality control issues to shoe manufacture.

As will be appreciated, conventional high-heeled shoes (such as that shown in FIG. 1) place the wearer's foot substantially on an inclined plane. Thus, when standing or walking, the foot pushes forward into the toe box due to gravity. This results in pressure on the ball (ball) or forefoot region and toe entrapment, which often results in burning sensations in these areas of the foot, as well as fatigue and discomfort in the foot and other areas of the body.

Numerous proposals have been made to enhance the comfort of high-heeled shoes, including those in my previous patents and publications. For example, in the article on Current Podiatric Medicine pages 29-32, 1990, 2 months I describe a high-heeled shoe design in which the portion of the shoe under the heel does not form a continuous slope from the arch down to the ball, but rather the portion under the heel is relatively parallel to the ground. This design uses a stiff plastic molded midsole that is concave to accommodate the heel and is sloped to bring the heel into a plane more parallel to the ground. In addition, a metatarsal pad is incorporated into the molded midsole.

In us patent No.5,373,650, i propose an under heel orthotic device. The orthotic device is a rigid or semi-rigid shell under the heel that extends forward with arch support to a point behind the metatarsal heads of the foot. The heel in the device is supported parallel to the ground or slightly inclined backwards.

In U.S. patent No.5,782,015, i have described a high-heeled shoe design in which the heel is positioned more parallel or slightly downwardly inclined relative to the shin plane and which has an arch support that supports the navicular bone in substantially the same plane as the wearer's heel anatomy. My PCT publication WO98/14083 (published 4/9 of 1998) describes a rigid molding apparatus that includes a heel depression and an anatomically shaped arch shaped implement.

There are many examples of designs used by others to improve the comfort of high-heeled shoes. U.S. patent nos. 1,864,999, 1,907,997, 4,317,293, 4,631,841, 4,686,993, 4,932,141 and 6,412,198 each describe shoe inserts or orthotic devices for improving the comfort of high-heeled shoes. Several of which relate to arch support. Some are hard; others have suggested cushions as a means of improving comfort. The inserts and orthotic devices of the prior art are typically relatively bulky and can affect the fit of the shoe if added by the wearer after manufacture. Other prior art proposals to improve wearer comfort require: each last used to manufacture the shoe is modified to change the shape of the shoe itself.

These prior art configurations improve comfort by supporting or cushioning portions of the foot and/or changing the angle of the foot to reduce forward sliding and/or change the percentage of the wearer's weight that different portions of the foot bear. In particular, their teachings suggest placing the heel on a more horizontal plane to shift weight back onto the heel, support the arch, adjust the toes upward, and/or cushion the surface on which the greatest proportion of weight is borne.

Disclosure of Invention

The present invention provides a thin flexible shoe insert that can be easily adapted to any style of shoe and that can be incorporated into a shoe without the need to change the last and associated manufacturing complexity. The insert has two slightly raised portions located under the heel and metatarsals. Although this insert has only two slightly raised areas, it significantly increases the comfort of the wearer, even if the heel is very high. The insert does not require the heel to be repositioned to a plane with the floor as in some prior art. The insert can be very thin except at these two slightly raised portions, thereby minimizing any effect on shoe fit and avoiding any adverse effect on shoe style or appearance. Alternatively, a thin flexible insert can be placed in the shoe by the wearer.

According to the present invention, there is provided an apparatus for insertion into a high-heeled shoe and a corresponding method of constructing a shoe using the apparatus. The device includes (a) a posterior region positioned to underlie the calcaneus at least in a region anterior to the tuberosity of the calcaneus, an upper surface of the posterior region having a raised portion that gradually rises from a posterior of the device to a crescent-shaped apex, the apex underlying the region anterior to the tuberosity of the calcaneus; and (b) a forward region positioned to underlie at least a portion of the metatarsal shafts, the upper surface of the forward region having a raised portion that gradually rises to an apex underlying the second and third metatarsal shafts of the wearer. In the preferred embodiment, the device has a bridging or intermediate region connecting the front and rear regions, the device is flexible and the upper surface of the device is smoothly contoured between all regions. A feature and advantage of the apparatus of the present invention is that the apparatus can be universally applied to conventional high-heeled shoes without the need to change the shoe or last. With the device according to the invention, the shoe can be constructed by incorporating the device into the shoe during the manufacturing process, or the device can be applied by the wearer after manufacture.

Drawings

FIG. 1 is a schematic cross-sectional view of the bones of the foot and a partially exploded view of those portions of a conventional high-heeled shoe that underlie the sole of the foot.

FIG. 2 is a top plan view of one embodiment of the apparatus of the present invention.

FIG. 3 is a cross-sectional side view of the apparatus of the present invention shown in FIG. 2 taken along plane "III-III".

Fig. 4 is a cross-sectional side view of the apparatus of fig. 2 taken along the plane "IV-IV".

Fig. 5 is a schematic cross-sectional view of the bones of the foot and a partially exploded view of those portions of a conventional high-heeled shoe located beneath the sole of the foot into which the apparatus of the present invention shown in fig. 2 has been inserted.

Fig. 6 is a plan view of an alternative embodiment of the present invention.

Detailed Description

In the present invention, a device is provided that improves comfort and is easy to install in high-heeled shoes. For the purposes of this invention, high-heeled shoes are understood to include all footwear having a heel of about 1 inch or greater. The benefits of the invention are obtained when the raised portion is positioned in the shoe under the metatarsal shaft and heel. Typically, the device of the present invention is positioned on an insole or sock liner of a high-heeled shoe. Preferably, the device is sufficiently flexible so that it readily conforms to the upper surface of the insole board or sock liner on which it is positioned. The device may be made of any material known to those of ordinary skill in the art that can be molded or shaped and that will produce a device that is flexible under the conditions of general use of the shoe, while still maintaining sufficient dimensional stability to retain the benefits of the present invention.

In this preferred embodiment, the device is shaped to underlie at least: (i) extending from the edge of the calcaneal tuberosity to the heel portion of the foot located immediately forward of the calcaneal tuberosity and (ii) the area under the second and third metatarsal shafts. The device may extend beyond these areas and may be shaped to conform to the shape of the sock liner or insole board. Optimally, the device is narrower than the pad when it is to be positioned under the pad. This narrower dimension allows the edge of the insert to adhere to the insole board along the edge of the device of the present invention. Such a narrower configuration may be particularly desirable depending on the style of the shoe.

The device has two distinct raised portions: a first pronounced raised area that rises from the front edge of the tuberosity of the calcaneus to a crescent-shaped apex below the calcaneus in the area in front of the tuberosity of the calcaneus of the wearer's foot, and a second pronounced raised area that is positioned within the shoe to lie below the metatarsal shafts of the wearer's foot with its apex below or between the second and third metatarsal shafts. The first and second raised portions are connected by a bridge or intermediate region. For clarity, it will be understood that references to narrow and wide mean the side-to-side dimension of the shoe or device, and references to raised, lowered, thin, deep or high mean the vertical dimension of the device.

Fig. 3-5 show exemplary embodiments of a device 100 consistent with the present invention. The device 100 is formed from a flexible material, such as a molded flexible plastic or rubber, such as polyurethane, thermoplastic elastomer (TPE), thermoplastic rubber (TPR), polyvinyl chloride (PVC), or Ethylene Vinyl Acetate (EVA). The raised portion of the device has a shore a hardness of between about 20 and 90, and preferably between about 30 and 50, and most preferably about 40. The entire device preferably, but not necessarily, has the same hardness. The device 100 has a metatarsal end 110 and a heel end 120. The device includes two raised portions 130 and 140. The first raised area 130 positioned in the rear region is generally crescent-shaped and is positioned beneath an area within the shoe immediately forward of the tuberosity 23 of the heel bone or calcaneus 22 of the wearer's foot. The crescent shaped first raised area 130 is raised from the rear of the device so that the crescent is oriented as shown in fig. 3-5. The term "raised portion raised from the rear of the device" as referred to herein means the direction of the rise and the orientation of the crescent. Thus, when the device extends down beyond the calcaneal tuberosity, it will be understood that the raised portion need not, and preferably should not, be raised from the end of the device.

The second raised area 140 is located in the forward region and is positioned below the metatarsal shafts 47 of the wearer's foot. Most preferably, the apex of the second raised area is located below or between the second and third metatarsal shafts. The second raised area comprises a generally circular or oval shape that rises toward the metatarsal heads to an apex. The forward raised portion preferably has a thinner appearance located toward heel end 120 and a wider appearance located toward front end 110.

The apex of the raised area is preferably 2 to 8mm higher than the upper surface of the device immediately forward of the forward raised area under the metatarsal shafts and immediately rearward of the raised area under the calcaneus. In this preferred embodiment, the apexes have similar or identical heights. Preferably, each apex is higher for higher high-heeled shoes and lower for lower high-heeled shoes. And each apex is preferably lower for smaller size shoes and higher for larger size shoes. In the most preferred embodiment, each apex is about 3mm for an 18.6 (U.S. size 1) lady shoe and about 6mm for a 31.3cm (U.S. size 16) lady shoe with a heel height of 1 to 5 inches (or in other equivalent shoe sizes, such as uk, europe and japan). Generally, the size of the protrusion (in terms of height and area) is proportional to the size of the shoe, and the general rule of proportionality applies to the length of the shoe, and the width of the shoe increases with increasing size. However, it has been found that a small range of sizes enables the same device to be used without the significant loss of increased comfort associated with the device. The limiting factor in the comfort achieved with the device of the present invention is shown by the location of the apexes of the two raised areas-below the calcaneus but in front of the calcaneal tuberosity and below the medial metatarsal but behind the metatarsal heads.

The proximal and distal ends of the device (i.e., behind the heel and under the front of the raised portion 140) are relatively thin relative to the raised portion. Preferably, the depth of these proximal and distal ends is such that they are flush with the upper surface of the upper that wraps around the upper surface of the insole. Preferably, the end portions are also shaped to conform somewhat to the area extending between the edges of the upper on the inner bottom surface. The thickness of these ends of the device is typically from 0.2 to 1 mm.

The bridging or intermediate section or region of the device between the first raised portion 130 and the second raised portion 140 is preferably also relatively thin with respect to the raised portions. The thickness of this region is dictated in part by structural integrity issues during the shoe manufacturing process. This area can have a stronger material and ideally should not exceed 1mm thick. In general, this bridging or intermediate section or region must be thinner than raised portions 130 and 140, and preferably no more than about 4 millimeters thick, more preferably no more than about 2 millimeters thick for a U.S. size 6 ladies shoe and no more than about 3 millimeters for a U.S. size 10 ladies shoe (or equivalent dimensions in other shoe sizes). This thinner bridging or middle region allows the device to more easily conform to the shape of the insole. The minimum width of this bridging or intermediate region is also specified in view of manufacturing, and the optimum minimum width is that which maintains the geometry of the anterior and posterior regions relative to each other. The maximum width is the width that will not interfere with the appearance of the shoe. Preferably, this bridging or intermediate area is narrower than the insole board and, like the ends of the device, is flush with the upper surface of the upper surrounding the insole board and generally conforms to the shape of the area formed by the edges of the upper on the insole board. Fig. 6 depicts an alternative embodiment 200 of the device in which the front area 210 and the middle or bridging area are narrower than the rear area 220. The anterior apex is element 240 and the posterior apex is element 230.

It should be noted that in contrast to the teachings of the prior art, rather than providing raised portions to support the arch of the wearer's foot in the device of the present invention, at least a portion of the bridging or intermediate region underlying the arch is thinner than the apexes of the first and second raised portions 130, 140. That is, when a conventional arch support would normally be positioned in the shoe, at least a portion of the area under the arch is empty or lower than adjacent areas leaving the arch partially unsupported.

Preferably, the contour of the upper surface of the device is smooth, without sharp transitions or edges that could cause discomfort. In particular, the transition between the apex of the raised portion of the device and the surrounding area is smooth.

As described above, the present invention contemplates a single flexible device incorporating two raised areas. The present invention also contemplates two separate flexible devices, each containing one of the raised portions described above and which together achieve the advantages of the present invention. The invention also contemplates a single flexible device that contains one or the other of the raised portions described above and which is used with a shoe or shoe component that incorporates the other raised portion. Finally, the present invention contemplates a shoe incorporating any of the foregoing embodiments of the apparatus.

The device 100 is preferably positioned in the shoe 50 during the manufacturing process. Accordingly, the present invention also provides a method of constructing a high-heeled shoe, comprising: (a) assembling the vamp, the inner sole and the sole; (b) mounting a flexible device on the insole, the flexible device comprising (i) a posterior region positioned below the calcaneus in a region anterior to the anterior edge of the calcaneus tuberosity, an upper surface of the posterior region having a portion that gradually bulges from a posterior of the device to a crescent-shaped apex, the apex located below the region anterior to the calcaneus tuberosity; (ii) a forward region positioned beneath at least a portion of the metatarsal shafts, the upper surface of the forward region having a portion that gradually bulges from a location posterior to the metatarsal heads to an apex beneath the second and third metatarsal shafts; (iii) a bridging or intermediate region connecting the front and rear regions; and (iv) the upper surface of the device transitions smoothly between all regions; and (c) securing the insert to the insole board and the device. The order in which these steps are performed is a manufacturer's choice. In a preferred embodiment of the invention, the device 100 is positioned on the insole 53 of the shoe 50, and then the insert 54 is attached to the insole and the insoleThe top of the apparatus 100. It is also contemplated that in certain embodiments the device 100 may be installed after manufacture or after sale, such as by placement on the insole 53 or the sock liner 54 after manufacture. The device 100 may also be attached to a substrate by means such as glue, Pressure Sensitive Adhesive (PSA), hook and loop (e.g., adhesive tape) Or mechanical fasteners such as staples or staples, are attached to the insole board 53 and the sock liner 54. In general, any means that will hold the raised portion of the device in place can be used to position the device within the shoe. The device 100 also need not be separate from the pad but may be integral with the pad.

To facilitate correct positioning of the device, the device may be provided with markings or structures that orient the device. These markers may be arrows or the device itself may be configured with points for orienting the device.

The two raised portions may be formed as separate components and separately positioned in the shoe. In this case, the area between the two raised portions of the device is integral with the insole board or sock liner and need not be flexible. Yet another alternative manufacturing option is to incorporate a raised portion into the insole board and this incorporated raised portion need not be flexible either. Another alternative is to incorporate one or both of the raised portions into the pad. However, for ease of manufacture, a single device having separate raised portions connected by bridging or intermediate sections is preferred. In all cases, the portions of the device that are mounted on the insole must be sufficiently flexible to readily conform to the upper surface of the insole to which they are to be mounted.

The apparatus of the present invention provides unexpected advantages over the prior art. For example, although the posterior ridge is only a few millimeters high, the device shifts the weight carried by the foot significantly toward the heel and away from the forefoot region of the foot. Thus, the device reduces toe pain and general low back pain associated with wearing heeled shoes. Thus, foot pain associated with the use of high-heeled shoes specifically is reduced or avoided with such a device. The device also repositions the ankle for increased stability.

In addition, the apparatus does not require any changes in the last used to manufacture conventional shoes; rather, the device can simply be placed in a conventionally constructed shoe by the manufacturer or wearer. The device also does not significantly affect the fit of the shoe, as it does not substantially intrude into the shoe and thereby reduce the space available for the foot.

Claims (20)

1. An apparatus for insertion into a high-heeled shoe, comprising:

a. a posterior region having a first upper surface and positioned at least beneath a wearer's calcaneus region in front of an edge of a calcaneus tuberosity, the first upper surface of the posterior region having a first raised portion that gradually rises from a posterior of the device to a generally crescent-shaped apex located immediately below the calcaneus region of the calcaneus tuberosity in front of the calcaneus tuberosity;

b. a front region having a second upper surface and positioned to underlie at least a portion of the metatarsal shafts of the wearer, the second upper surface of the front region having a second raised portion that gradually rises to an apex underlying the second and third metatarsal shafts of the wearer;

c. a middle region having at least one thinner portion than the apexes of the posterior and anterior regions, the middle region connecting the anterior and posterior regions;

wherein the first and second upper surfaces are smoothly contoured, an

Wherein the apparatus causes weight carried by a wearer's foot to move toward the heel and away from the forefoot region of the foot.

2. The device of claim 1, wherein the apex of the second raised portion of the anterior region is 2 to 8mm high relative to the surface immediately anterior to the second raised portion.

3. The apparatus of claim 2, wherein the height of the apex of the second raised area of the forward region is proportional to the size and height of the shoe.

4. A device according to claim 3, wherein the apex of the second raised portion of the forward region ranges from 3mm for an 18.6cm, usa size 1 ladies shoe to 6mm for a 31.3cm, usa size 16 ladies shoe.

5. The device of claim 1, wherein an apex of the first raised portion of the posterior region is 2 to 8mm high relative to a surface immediately posterior to the first raised portion.

6. The apparatus of claim 5, wherein a height of an apex of the first raised area of the rear region is proportional to a size and a height of the shoe.

7. The apparatus of claim 6, wherein the apex of the first raised portion of the rear region ranges from 3mm for an 18.6cm, U.S. size 1 lady shoe to 6mm for a 31.3cm, U.S. size 16 lady shoe.

8. A device according to claim 1, wherein the anterior second raised area is shaped to widen toward the metatarsal head of the wearer and taper toward the posterior aspect of the metatarsal axis.

9. The device of claim 8, wherein the second, front raised portion is ellipsoidal.

10. The device of claim 1, wherein the device is flexible.

11. The device of claim 1, wherein the thinner portion extends from a medial side of the device to a lateral side of the device.

12. The device of claim 1, wherein at least the intermediate region is flexible.

13. The device of claim 1, wherein the first and second raised portions are the thickest portions of the device.

14. The device of claim 1, wherein the thickness of all portions of the device other than the first and second raised portions and the transition from the first and second raised portions to the remainder of the device is no more than 1 mm.

15. The device of claim 1, wherein the first and second raised portions of the posterior and anterior regions have about the same height.

16. The apparatus of claim 1, wherein at least the first and second raised portions have a shore a hardness of 20 to 90.

17. The apparatus of claim 16, wherein at least the first and second raised portions have a shore a hardness of 35 to 50.

18. The apparatus of claim 17, wherein at least the first and second raised portions have a shore a hardness of about 40.

19. The apparatus of claim 16, wherein the entire apparatus has about the same shore a hardness throughout.

20. An apparatus for insertion into a high-heeled shoe, comprising:

a. a posterior region having a first upper surface and positioned at least beneath a wearer's calcaneus region in front of an edge of a calcaneus tuberosity, the first upper surface of the posterior region having a portion that gradually bulges from a posterior of the device to a generally crescent-shaped apex located immediately below the calcaneus region in front of the calcaneus tuberosity;

b. a front region having a second upper surface and positioned to underlie at least a portion of the metatarsal shafts of the wearer, the second upper surface of the front region having a portion that gradually bulges to an apex underlying the second and third metatarsal shafts of the wearer;

c. a middle region at least a portion of which is thinner than the apexes of the posterior and anterior regions, the middle region connecting the anterior and posterior regions;

wherein the front region and the middle region are narrower than the rear region; wherein the apparatus causes weight carried by a wearer's foot to move toward the heel and away from the forefoot region of the foot.