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

Abstract

Provided is a device for insertion into a heeled shoe, having a rear region positioned to underlying a wearer's calcaneal tuberosity, the rear region being shaped to accommodate a planer surface of the wearer's calcaneal tuberosity, an upper surface of said rear region having a raised portion underlying an area of the wearer's calcaneus immediately forward of the wearer's calcaneus tuberosity; and a forward region positioned to underlie at least a portion of the shafts of the wearer's metatarsals, the second upper surface of said forward region having a raised portion which gradually rises to an apex position to underlie the shafts of the wearer's second and third metatarsals.

Claims

1. A device for insertion into a heeled shoe, the device comprising: a rear region having a foot supporting surface configured to underlie a wearer's calcaneal tuberosities; a forward region having a foot supporting surface configured to underlie at least a portion of the shafts of the wearer's metatarsals, wherein the rear region and the forward region are capable of being joined by a middle region or can also be separate from one another; a lateral side; and a distal side; wherein the rear region foot supporting surface includes first and second elongated ellipsoid-shaped depressed region, the first elongated ellipsoid-shaped depressed region being larger in area and deeper than the second elongated ellipsoid-shaped region to underlie respectively the lateral and medial tuberositites of the wearer's calcaneus; wherein the first elongated ellipsoid-shaped depressed region has an elongate axis running in a rear-to-forward direction of the device and skewed in a direction towards the medial side of the device; wherein the second elongated ellipsoid-shaped depressed region has an elongate axis running in a rear-to-forward direction of the device and skewed in a direction towards the lateral side of the device; wherein the second elongated ellipsoid-shaped region is shorter in length than the first elongated ellipsoid-shaped region; wherein an upper surface of said rear region has a raised portion configured to underlie an area of the wearer's calcaneus forward of the wearer's lateral and medial tuberosities; and an upper surface of the forward region is configured to underlie at least a portion of the shafts of the wearer's metatarsals, the upper surface of said forward region having a raised portion which rises to an apex configured to underlie the shafts of the wearer's second and third metatarsals; and wherein the middle region is lower than the rear region raised portion and the forward region raised portion and is configured to leave the arch of the wearer unsupported in part.

2. The device of claim 1, wherein the first ellipsoid-shaped depressed region is larger in volume than the second ellipsoid-shaped depressed region by 40 to 120 percent.

3. The device of claim 1, wherein the forward region is raised by 1 degree to 10 degrees relative to the rear region.

4. The device of claim 1, wherein the first ellipsoid-shaped depressed region is about 0.3 mm deeper than the second ellipsoid-shaped depressed region.

5. The device of claim 1, wherein forward ends of the first and second elongated ellipsoid-shaped depressed regions rise to crescent shaped apices configured to underlie an area forward of the tuberosity of the calcaneus of the wearer.

6. The device of claim 5, wherein the device is 2 mm to 8 mm thick at a thickest location.

7. The device of claim 1, wherein the device is 2 mm to 8 mm thick at a thickest location.

8. The device of claim 1, wherein the device comprises a heel piece incorporating the rear region and a metatarsal piece incorporating the forward region.

9. The device of claim 1, wherein the left and right shoe pieces are mirror images of one another.

10. A heeled shoe having a device as claimed in claim 1 mounted therein.

11. A heeled shoe as claimed in claim 10, wherein the device is mounted or incorporated into an insole board or sock liner of the shoe.

12. A method for increasing comfort in heeled shoe comprising providing the shoe with a device as claimed in of claim 1.

13. The device of claim 1, wherein the device as installed in a shoe during construction of the shoe.

14. The device of claim 1, wherein the first elongated ellipsoid-shaped depressed region is 2.5 times larger in plan than the second elongated ellipsoid-shaped depressed region.

15. The device of claim 1, wherein the first elongated ellipsoid-shaped depressed region is 2.7 times larger in plan than the second elongated ellipsoid-shaped depressed region.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

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

(2) FIG. 1A is a rear view of the calcaneus.

(3) FIGS. 2A and 2B are top plan views of an embodiment of the device of the present invention showing right (FIG. 2A) and left (FIG. 2B) shoe devices.

(4) FIG. 3 is a side cross-sectional view of the device of the present invention shown in FIG. 2B, taken along plane III-III.

(5) FIG. 4 is a contour drawing of the device of FIG. 2A.

(6) FIG. 5 is a diagrammatic cross-sectional view of the foot bones and a partially exploded view of the portions of a conventional high-heeled shoe that underlie the sole of the foot into which the device of the present invention shown in FIG. 2 has been inserted.

(7) FIGS. 6A-6D are views, similar to FIGS. 2A and 2B, of an alternative embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

(8) As used herein heeled shoes shall include high heeled shoes, low heeled shoes and flats. The present invention provides a device which improves comfort and is easily installed in heeled shoes. For purposes of this invention, it is to be understood that heeled shoes include all footwear having a heel which is about one inch or higher. The benefits of the invention are achieved when a device is positioned in a shoe to underlie the metatarsal shafts and calcaneus of the wearer. Typically, the device is positioned on the insole board or sock liner of a 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 formed of any materials known to those of ordinary skill in the art that can be molded or shaped and that will produce a device flexible under normal conditions of use of a shoe, while retaining sufficient dimensional stability to retain the benefit of the invention.

(9) In the preferred embodiment, the device is shaped to underlie at least (i) the portion of the heel extending from the edge of the tuberosity of the calcaneus to the portion of the heel that is immediately forward of the tuberosity of the calcaneus, 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 sock liner when it is to be positioned under the sock liner. This narrower size allows the edge of the sock liner to be adhered to the insole board along the edges of the device of the invention. Depending on the style of the shoes this narrower configuration may be particularly desirable.

(10) The device has two distinct areas: a first distinct heel area that underlies the calcaneal tuberosities of the wearer, and which has two depressed areas shaped generally to accommodate respectively the lateral and medial tuberosities of the wearer's calcaneal anatomy. The depressed areas rise from their respective forward edges of the tuberosity of the calcaneus to a crescent-shaped apices underlying the calcaneus in the area forward of the tuberosity of the calcaneus of the wearer's foot. The device also includes a second distinct raised area located within a shoe to underlie the metatarsal shafts of the wearer's foot, with its apex under or between the second and third metatarsal shafts. The first and second raised areas are joined by a bridging or middle region. For clarity, it is to be understood that references to narrow and wide mean the side-to-side dimensions of the shoe or device while references to raised, lowered, thinness, depth or height mean the vertical dimensions of the device.

(11) FIGS. 2-5 illustrate an exemplary embodiment of a device 100 consistent with the invention. The device 100 is formed from a flexible material, e.g., molded flexible plastic or rubber, such as polyurethane, thermoplastic elastomer (TPE), thermoplastic rubber (TPR), polyvinyl chloride (PVC) or ethylene vinyl acetate (EVA). The raised areas of the device have a Shore A hardness between about 15 and 70, and preferably have a Shore A hardness of about 20 to 50, and most preferably about 35. The entire device preferably but not necessarily is of the same hardness. The device 100 has a forward region 110 and a rear region 120. The device includes three raised areas 130, 135 and 140. Raised areas 130 and 135, located in the rear region, are generally crescent-shaped and positioned in a shoe to underlie the area immediately in front of the tuberosity 23 of the heel bone or calcaneus 22 of the wearer's foot. The crescent-shaped raised areas 130 and 135 rise from depressions as will be described below found in the heel portion of the device so that the crescents are oriented as shown in FIGS. 2-5.

(12) Referring in particular to FIGS. 2A-2B, FIG. 3 and FIG. 4, the device includes a lop-sided generally cardioid shaped depression including a first depressed area 136 located directly under the lateral tuberosity of the wearer's calcaneal anatomy, and a second depressed area 138 located under the medial tuberosity of the wearer's calcaneal anatomy. The base level of depressed area 136 under the lateral tuberosity is slightly higher, typically about 0.1-3 mm higher, preferably about 0.1-2 mm higher, most preferably about 0.3 mm higher, over the base level of depressed area 138 under the medial tuberosity to accommodate the calcaneal tuberosity of the wearer. Depressed area 138 under the medial tuberosity is 2-5 times larger in plan, preferably 2-4 times larger, more preferably 2-3 times larger, most preferably about 2.7 times larger in plan, than the area 136 under the lateral tuberosity. Both depressed areas 136 and 138 are generally ellipsoid in shape. More particularly, the first and second depressed areas 136, 138 can be described as first and second depressed areas, defined by the Boolean subtraction of the larger of two 3D ellipses from the smaller, the larger ellipse being 40 to 120 percent larger in volume than the smaller ellipse, preferably 60 to 100 percent larger in volume, more preferably about 80 percent larger in volume than the smaller ellipse with larger skewed to the medial side and the smaller skewed to the lateral, with the intersecting volume being 10 to 30 percent of the larger, more preferably about 20 percent of the larger, with the longer axis of both aligned with the heel/toe direction of the device, and with the medial/lateral axis of the smaller skewed slightly to the rear of the larger, and both rotated such that the toe-ward end is raised 1 to 10 degrees, preferably 3 to 8 degrees, more preferably about 5 degrees relative to the heel-ward end, such depressions being configured to accommodate respectively the lateral and medial tuberosities of the wearer's calcaneus.

(13) A third raised area 140 is located in the forward region of the device which is canted to the medial side, and is positioned to underlie the metatarsal shafts 47 of the wearer's foot. Optimally, the apex of the third raised area 140 is located under or between the second and third metatarsal shafts. The third raised area 140 comprises a generally rounded or ellipsoid shape that rises to an apex in the toeward direction of the metatarsal heads. The forward raised area 140 preferably has a thinner aspect located towards the heel end and a wider aspect located towards the toeward end. Since the device includes a lop-sided section under the heel region, and the toeward region is canted to the medial side, the device is left/right shoe specific, the left and right pieces being mirror images of one another.

(14) The apices of raised areas 130, 135 and 140 are 2 to 8 mm higher relative to the bottom surface of the device and, preferably 2 to 6 mm higher, more preferably 2.5 to 4.5 mm, most preferably about 3.8 mm higher relative to the bottom surface of the device measured immediately forward of the forward raised area under the metatarsal shafts and immediately rearward of the raised areas under the calcaneus. In a particularly preferred embodiment each apex 130, 135 and 140 is approximately 3.3 mm high for a US size 1 women's shoe, approximately 3.9 mm higher for a US size 6 woman's shoe, and approximately 5.2 mm for a US size 16 women's shoe high relative to the bottom surface of the device (or their equivalents in other, e.g. English, European and Japanese shoe size scales) having a heel height of 1 to 5 inches. A bridge area 160 separates depressed areas 136 and 138, and is also depressed relative to the upper surface of the device surrounding the depressed areas 136 and 138. In the preferred embodiment the apices 130, 135 and 140 are of similar or the same height. Preferably, each apex 130, 135 and 140 is higher for higher heeled shoes and lower for lower heeled shoes. Also, each apex 130, 135 and 140 preferably is lower for smaller sized shoes and higher for larger sized shoes. The size of raised areas 130, 135 and 140 also changes somewhat with shoe size with the size of the area increasing with increasing length and/or width. Typically, the size of the raised areas both in terms of height and area is scaled to the shoe size with normal rules of scaling applying as the length and width of the shoes increases with increasing size. However, it has been found that a small range of sizes can use an identical device without significant loss of the improved comfort associated with the device. The critical factor on the comfort achieved with the device of the invention appears to be the location of the two raised regionsunder the calcaneus but forward of the tuberosity of the calcaneus, and under the middle metatarsals but rearward of the heads of the metatarsals, and the size and location of the depressed areas under the calcaneus tuberosity.

(15) Heel size from individual to individual typically varies far less than other aspects of foot dimensions. Accordingly, the depressed areas 136 and 138 under the calcaneus tuberosity may be made essentially the same for all toot sizes provided the area under the medial tuberosity 138 is far larger than under the lateral tuberosity 136, and the base level of the depressed area 136 under the lateral tuberosity is somewhat higher over the base level of the depressed area 137 under the medial tuberosity. The proximal and the distal ends of the device, i.e., underlying the back of the heel and forward of raised area 140 are thin relative to the raised areas. Preferably these proximal and distal ends have a depth that results in their being flush with the upper surface of the shoe upper where it wraps around the upper surface of the insole board. Preferably the ends are also shaped to conform somewhat to the area extending between the edges of the upper that lie on the surface of the insole board. The thickness of these ends of the device typically will be from 0.2 to 1 mm thick.

(16) The bridging or middle section or area of the device between the first raised areas 130, 135 and the second raised area 140 is also preferably thin relative to the raised areas. The thickness of this area is in part dictated by issues of structural integrity during the manufacturing process for the shoe. With stronger materials this area can, and ideally should be, no more than a millimeter thick. In general, this bridging or middle section or area must be thinner than the raised areas 130, 135 and 140, and preferably is no more than about 4 millimeters thick, more preferably about 2 mm thick for a US size 6 women's shoe and about 2 mm for a US size 10 women's shoe (or their equivalents in other size scales). 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 middle region is also dictated by manufacturing considerations with the optimal minimum width being that which will maintain the geometry of the forward and rear regions relative to each other. The maximum width is that which will not interfere with the appearance of the shoe. Preferably this bridging or middle region is narrower than the sock liner 54 and, like the ends of the device, the bridging or middle region sits flush with the upper surface of the upper that wraps around the insole board and generally conforms to the shape of the area created by the edges of the upper on the insole board.

(17) It should be noted that, contrary to the teachings of the prior art, rather than providing a raised area for supporting the arch of the wearer's foot in the device of the present invention, at least a portion of the bridging or middle region underlying the arch is thinner than the apices of the first and second raised areas 130, 140. That is to say, where a traditional arch support normally would be located in the shoe at least a portion of the area underlying the arch of the foot is hollowed or lower than adjacent areas leaving the arch unsupported in part.

(18) Preferably, the upper surface of the device is smoothly contoured, with no sharp transitions or edges that could contribute to discomfort. Specifically, the transition between the apices of the raised areas and the surrounding areas of the device are filleted and smooth.

(19) As described above, the invention contemplates a single flexible device into which both raised areas are incorporated. As shown in FIGS. 6A-6D, the invention also contemplates two separate flexible devices, a heel area elements 300A/300B and metatarsal area elements 302A/302B, which together achieve the advantages of the invention. More specifically, FIGS. 6A-6D show an alternative embodiment of the device in which the metatarsal elements 302A/302B have raised areas 304A/304B similar to raised area 140 of the FIG. 2A/2B embodiment, and the heel area elements 300A/300B have depressed areas 306A/306B and raised areas 310A, 310B, 312A, 312B, similar to depressed 138/136 and 130/135 of the FIG. 2A/2B embodiment. In the FIG. 6A-6D embodiment, the heel piece, and the metatarsal piece are individually positioned in a shoe. In that case, the region between the two pieces of the device is integral with the insole board or the sock liner and need not be flexible. A further manufacturing alternative is to incorporate one or both of the heel portion and metatarsal piece into the insole board. Yet a further alternative is to incorporate one or both of the heel portion and the metatarsal piece into a sock liner. However, for ease of manufacture, a single device having the separate raised areas joined by a bridging or middle section is preferred. In all cases, the portions of the device that are mounted on the insole board of a shoe must be flexible enough to readily conform to the upper surface of the insole board on which they are mounted. The invention also contemplates a single flexible device which embodies one or the other of the above raised areas and which is used in conjunction with a shoe or shoe part which incorporates the other raised area. The invention also contemplates using only the heel area element 300 as a heel cup. This latter embodiment has particular utility in sport shoes, particularly where the wearer is subjected to a lot of lateral movement, such as tennis and basketball. Finally, the invention contemplates shoes into which any of the foregoing described embodiments of the device has been incorporated.

(20) The device 100 preferably is positioned in shoe 50 during the manufacturing process. Accordingly, this invention also provides a method of constructing a heeled shoe comprising: (a) assembling an upper, insole board and sole; (b) mounting above the insole board a flexible device comprising (i) a rear region positioned with its depressed areas to underlie the calcaneus tuberosity of the wearer; (ii) a forward region positioned to underlie at least a portion of the shafts of the metatarsals, the upper surface of said forward region having a portion which gradually rises to an apex positioned to underlie the shafts of the second and third metatarsals from a position behind the heads of metatarsals; (iii) a bridging or middle region which connects said forward and rear regions; and (iv) the upper surface of said device transitioning smoothly between all regions; and (c) affixing a sock liner to the insole board and to the device. The order in which these steps are done is the choice of the manufacturer. In a preferred embodiment of the invention, the device 100 is positioned on the insole board 53 of the shoe 50, and then a sock liner 54 is adhered to the top of the insole board and the device 100. It is also contemplated that the device 100 may be installed post-manufacture or post-sale in certain embodiments, e.g., by being placed on the insole board 53 or sock liner 54 post-manufacture. The device 100 may be attached to the insole board 53 and the sock liner 54 through means such as glue, pressure-sensitive adhesive (PSA), hook and loop fasteners, or mechanical fasteners such as nails or staples. In general, any means that will cause the raised areas of the device to remain in position may be used to position the device in the shoe. Device 100 also need not be separate from the sock liner but may be integral with the sock liner.

(21) In order to facilitate proper positioning of the device, the device may be provided with markings or structures that orient the device. These markings may be arrows or the device itself may be configured with points which serve to orient the device.

(22) The device of the present invention provides unexpected advantages over the prior art. For example, although the device is only a few millimeters thick, the device causes the weight borne by the foot to be significantly shifted towards the heel and off the ball of the foot. As a result, the device reduces toe pain and general lower back pain associated with the wearing of heeled shoes. Thus, foot pain, endemic with the use of heeled shoes including specifically high-heeled shoes, is reduced or eliminated using the instant device. The device also improves ankle stability.

(23) In addition, this device does not require any change in the lasts used to manufacture conventional shoes; rather, the device can simply be placed into the conventionally constructed shoe either by the manufacturer or by the wearer. Nor does this device significantly affect the fit of the shoe as it does not intrude substantially into the shoe and thereby diminish the space available for the foot.