HK1020305A - Shoe and method of making same - Google Patents

Description

Shoe and method of making same

The present invention relates generally to footwear, and more particularly to footwear structures for use in walking and other activities. The invention has particular utility in high-heeled shoes, and will be described with particular reference thereto, although other applications are contemplated.

The evaluation of high-heeled shoes made by the prior and currently used techniques is extremely uncomfortable and investigations have shown that 20% of conventional high-heeled shoe users experience immediate foot pain from wearing such shoes, and that most users experience foot pain within four hours. This discomfort is primarily caused by the wearer's foot slipping forward in the shoe causing the wearer's toes to be compressed at the front of the shoe.

Referring to FIG. 1, the bone structure of one foot in a conventional high-heeled shoe is shown in dotted and dashed lines. The structure of the foot includes the calcaneus 10 (also known as the tarsal bones), the arch area, and the phalanges 13, the calcaneus 10 including the talus and the calcaneus, and the arch area including the ancient festival in spring and autumn held on water banks to drink and cleanse away the evil influences-shaped bones 11 and the metatarsals 12. The calcaneus 10 is supported by the calcaneus seat 19 as the arch area of the foot extends over the central sole reinforcement 15 in the shoe to the ball 16 at the junction of the metatarsals of the foot and the base of the phalanges 13. The ball of the foot underlies the metatarsal heads to form the metatarsals, and the phalanges are supported by the toe region 9 of the shoe.

This shoe is shown in figure 1 as having a heel height of approximately 2 inches. The shoe shown is women's shoe number 7 according to the american standard. The shoe is placed on the base surface 18 with a heel height "a" measured from the base surface 18 to the heel seat 19. The heel seat 19 is inclined upwardly at an angle of about 12-15 degrees relative to the base surface. The angle "X" can be seen in fig. 1 and 3. The central sole stiffening portion 15 is inclined in the shoe from the receptacle at an angle of about 30 degrees forward and downward relative to the base plane. The angle "Y" can be seen in fig. 1 and 3. The big toe of the toe portion in the shoe should be essentially parallel to the base but may be inclined upwardly and forwardly due to the toe portion having an angle of 2-3 degrees upwardly and forwardly relative to the base 18. This angle "Z" can be seen in FIGS. 1 and 3.

It will be appreciated that a conventional high-heeled shoe shown in figure 1 substantially places the wearer's foot in an inclined plane so that the foot is forced to proceed to the toe box when standing or walking. This causes a compressive sensation in the ball bone or forefoot and toe squeeze, often resulting in a burning sensation, fatigue and discomfort in this part of the foot.

Traditionally, shoes have been manufactured in one of two basic processes, namely, sliding upper shoes (slip) and board upper shoes (board). A sliding upper is a shoe that is typically stitched together with an upper and then glued or sewn to the center sole and/or the outer sole. The upper is glued or sewn to a flat or pre-molded plate and then glued to the sole and/or outsole. In order not to collapse the shoe and to properly support the wearer's weight, a reinforcement, commonly referred to as a mid-sole, typically made of metal, leather, fiberboard or plastic, is glued and/or sewn to the central sole and/or inner sole plate and the outer sole. Some footwear structures also use a molded insole liner, and/or an insole pad in the footwear to act as a shock pad for the foot. Although initially shock absorbing pads provide a comfortable feel to the foot in the shoe, in practice shock absorbing pads destroy the ergonomic properties of the shoe and do not contribute to the stability of the foot in the shoe or support the foot in an anatomically correct position.

The primary object of the present invention is to provide a shoe construction that is comfortable to wear while also allowing the wearer's foot to assume an anatomically correct support position within the shoe.

It is another object of the present invention to provide a method of manufacturing a shoe that provides a shoe structure that is comfortable to wear and also allows the wearer's foot to be placed in an anatomically correct support position in the shoe.

It is another object of the present invention to provide a device for varying the angle of inclination of the heel relative to the base surface which is adaptable to various heel heights and maintains the heel in a near parallel relationship with the base surface as the heel height changes when a woman wears high-heeled shoes.

Another object of the present invention is to provide a shoe construction that supports the longitudinal axis of the foot, but provides flexibility in the oblique axis. It would be useful, for example, in golf shoe designs that provide flexibility during swinging motions but prevent sagging of the longitudinal arch area of the foot during walking. In this application, the area under the medial longitudinal arch of the foot is reduced or completely removed to allow the arch of the foot to be lifted during a swing, while the central portion of the shoe maintains a rigid structure to prevent damage to the long axis.

Briefly, to achieve the foregoing and other objects, one aspect of the present invention provides a shoe construction having a rigid shape orthotic device comprising a heel cup and an anatomically shaped device in cross-section extending from a distal end to a proximal metatarsal head end, the device being rigidly affixed as a structural element to the upper surface of a shoe last/insole, the rigid device comprising a deep-cornered heel cup and extending from the heel to a location behind the metatarsal head region, being molded and/or machined to fit the underside of the foot so that the foot assumes an anatomically correct position in the shoe. As illustrated, the device of the present invention is similar to conventional foot orthotic devices. Unlike conventional foot orthoses, however, the device of the present invention includes an integral structural element in the shoe that is more stable to the wearer's foot in the shoe and may not require a separate midsole, thus serving a dual function.

In accordance with a preferred embodiment of the present invention, the stiffening means comprises a slightly downwardly inclined heel seat (relative to the imaginary mid-sole plane of the shoe) and an arch support means extending forwardly from the heel seat and having a first position to support the navicular forward end of the wearer, the shoe also includes a last (insole) plate extending forwardly and downwardly from the arch support first position and a toe support region extending forwardly and upwardly from the last (insole) plate at an angle whereby the first metatarsal of the wearer is supported by the phalanges to prevent forward sliding of the foot relative to the shoe and thereby prevent toe portions of the toe in the shoe from being compressed such that the weight borne by the heel seat will increase by about 16% or more relative to the weight of the wearer of a standard high-heeled shoe.

Other objects and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings, in which like reference characters designate the same parts throughout the figures thereof, and wherein:

figure 1 is a schematic cross-sectional view of a conventional high-heeled shoe made in the prior art.

Figure 2 is a schematic cross-sectional view of a high-heeled shoe made in accordance with the present invention.

Figure 3 is a schematic view showing a comparison of relative angles with respect to a base plane for a shoe made according to the present invention as shown in figure 2 and a conventional high-heeled shoe as shown in figure 1 having a similar heel height.

Figures 4 to 7 are views similar to figure 2 showing a high-heeled shoe made in accordance with the present invention and showing the application of the present invention to high-heeled shoes having various heel heights.

FIG. 8 is a side elevational view, partially in cross-section, showing a shoe made in accordance with one embodiment of the present invention.

Fig. 9 is an exploded view of fig. 8.

FIG. 10 is a perspective view, partially in cross-section, of the shoe of FIG. 8.

FIG. 11 is a perspective view of one element of the shoe of FIG. 8.

FIG. 12 is a view similar to FIG. 8 showing another embodiment of the present invention.

Fig. 13 is a cross-sectional view of fig. 12.

Fig. 14 is a side view showing how the present invention can be used to place and support a left foot.

Referring to FIG. 2, a preferred embodiment of the present invention is shown. As in the case of the shoe of FIG. 1, the shoe shown in FIG. 2 has a heel height of approximately two inches. Unlike the conventional shoe shown in FIG. 1, however, in the shoe of FIG. 2, the heel seat 20 rotates in a clockwise direction (in the direction of arrow CL) at an angle "H" to the sole relative to the base surface 18, according to the following equation:

h =5 ° + (α × 1.25 °) heel height segmented 1/2 "after α = more than 1".

An arch support 22 extends at least partially forward from the front edge of the heel base 20 to below the arch area of the wearer's foot. The arch support 22 is contoured with a high point 23 that forms a barrier to prevent the wearer from sliding forward in the calcaneus bone of the shoe, and the arch support 22 curves downward from the high point 23 to the sole 24 where it merges into the toe area 26 of the shoe.

The sole 24 is inclined at an angle "M" relative to the base plane according to the following equation:

m =18 ° + (α × 3.5 °) heel height segmented 1/2 "after α = more than 1".

Maintaining the above-described relationship of "M" and "H" with respect to heel height is critical to the present invention in order to prevent discomfort to the wearer caused by excessive height at high point 23. Thus, varying the M/H relationship with increasing heel height α will result in a change in the amount of weight applied to the heel of the wearer.

The toe region of the shoe is inclined forwardly and upwardly at an angle "T" of about 2-3 + -1 deg. relative to the base plane.

The downwardly inclined heel seat of the present invention is contoured to form an extended arch support 22 of the heel seat, the combination of the mid-sole inclination and the upward inclination of the toe area of the shoe, which allows a higher percentage of the wearer's weight to be carried or supported by the heel seat than in a conventional high-heeled shoe. Pressure measurements taken under the heel seat of the wearer and the ball of the foot in the shoe of a high-heeled shoe made in accordance with the present invention, respectively, as compared to a conventional high-heeled shoe of the same height, show that the high-heeled shoe made in accordance with the present invention provides an increase in weight bearing at the heel of the wearer of about 16-18%, while the weight bearing at the ball of the foot of the wearer decreases when walking and therefore the shoe of the present invention is designed so that a greater portion of the weight of the wearer is borne by the heel seat rather than being transferred to the sole and ball of the foot in the shoe, thereby avoiding toe compression and ensuring comfort.

Referring to fig. 3, the dashed lines show the angle of inclination H of the heel seat, the angle of inclination M of the first metatarsal, and the angle of inclination T of the big toe in the toe area relative to the base surface 18 of a high-heeled shoe made in accordance with the present invention. Alpha represents the heel height and the solid line in fig. 3 represents a set of angles and inclinations corresponding to a prior art high-heeled shoe (such as that shown in fig. 1), with a comparison of data for similar heel heights in accordance with the present invention. Prior art shoes have the heel seat inclined upwardly toward the rear of the shoe at an angle X of about 8 degrees, the first metatarsal inclined downwardly and forwardly at an angle Y of about 27 degrees, and the big toe inclined upwardly and forwardly at an angle Z of about 1 degree. These angles are relative to the base surface 18 and are relative to similarly sized shoes.

A mechanically concise explanation of the foot may be helpful in promoting understanding of the function of the shoe of the present invention. The foot may function in two separate mechanical ways to support the body. The foot acts primarily like a beam supporting the body in bending strain. The support mechanism is effective when the external force acting on the arch (force to flatten the arch) is relatively low. This occurs during the steps after the center of body weight falls behind the ankle joint. The forces that occur begin to cause the arch to flatten as the center of body weight passes through the ankle joint, as occurs in a normal forward step. In this regard, the foot initially changes from a supporting mechanical state to a truss support and then can be supported via compressive strain. Because the foot bones have been considered extremely strong in compressive strength, the greater the compressive strain, the better the arch support. To enable the foot to achieve this change in the support mechanism, the metatarsals must be supported by the flexed toes, which support effect prevents the metatarsals from slipping forward so that they can change from flexed to compressive support.

The design of the shoe of the present invention in which the heel seat is combined with the action, shape and inclination of the arch support provides the advantages of the present invention. By creating a special platform surface for the foot, a supporting effect is initiated in a more efficient manner preventing the metatarsal bones from sliding forward, as a result of which the problem of the toes thereafter being squeezed to the tip in the shoe is eliminated.

For example, to increase the angle of flexion, dorsi-flexion of the toes in the shoe may be achieved in one of two ways. The front end of the shoe can be raised upward to create a "fanciful" (genie) style shoe. While this would work, it would not be a particularly popular form. A more efficient mechanism allows the angle at which the metatarsals approach the sole to be increased. This has the effect of increasing the flexion of the toes without making a "funny" shoe. The increased angle of the metatarsal bones relative to the base plane can be achieved by changing the configuration of the rear of the shoe, particularly the angle of the heel seat 20, and by extending under the navicular bone of the wearer through the arch support as previously discussed. Because the joints of the foot are in various positions, the angle between the calcaneus (heel bone) and the base plane is compensated by the slope of the ball of the metatarsal bones approaching the foot. The angular relationship is inversely proportional, the more parallel the calcaneus is to the base plane (as long as there is a suitable heel height), the more the metatarsals approach an upright height, and thus the desired support can be achieved by providing a heel seat with a low slope to increase the angle of descent of the metatarsals.

In the present invention, the heel seat is kept inclined downward irrespective of the heel height in relation to the sole, and the navicular bone of the wearer is supported by the arch region extending forward from the heel seat. In prior art shoe designs, the higher the heel of the shoe, the closer the heel seat angle is to the sole angle. This correlation in the prior art shoe design art results in a platform with feet that are inclined toward the floor. This increased angle in turn causes the foot to slide forward and the toe portion to be compressed in the shoe. The present invention produces a shoe having a heel seat that slopes downward relative to the mid-sole regardless of heel height, and provides an arch region under the navicular bone of the wearer, supporting the navicular bone, thereby creating a flat surface such that a greater percentage of the wearer's weight is carried by the heel seat. The metatarsal angle (relative to the sole of the shoe) increases in proportion to the heel height, e.g., the higher the heel height, the larger the metatarsal angle relative to the floor. In shoes with a heel that is higher than 2 inches, the advantage is not increased metatarsal inclination, but rather as a result of the biomechanical changes in metatarsal inclination caused by maintaining the alignment of the heel seat closer to parallel to the base plane.

This effect is emphasized when the toe area is inclined as described above, in order to increase the elastic angle of the toes. Due to this particular design, the distribution of the load between the foot and the shoe is effective, so that when the wearer stands, the problems described above arise because a large part of the wearer's body weight is borne by the heel seat, rather than being transferred to the ball of the foot by the inclined surface of the prior art shoe. Thus, with the design of the present invention, toe compression is prevented and comfort is ensured.

While the above description corresponds to the standard U.S. woman's shoe 7, which has a 2 inch heel height, the present invention is specifically designed to be applicable to all general ranges of standard U.S. women's shoes, and to the range of 5-10; women's shoes are available in a variety of different heel heights and are particularly suited to heel heights ranging from 1 to 3 inches. With different shoe sizes and heel heights, the metatarsal inclination will vary, provided that a 1 inch heel height is within a range of about 18-22 degrees and a 3 inch heel height is within a range of about 33-36 degrees. Fig. 2 and 4-7 and table 1 below indicate that high-heeled shoes made in accordance with the present invention have heel heights of 1 inch (fig. 4), 1.vz inches (fig. 5),2 inches (fig. 2), 2.vz inches (fig. 6), and 3 inches (fig. 7).

TABLE 1

Heel high (alpha)	Heel seat inclined (H)	Metatarsal bone angle (M)	Toe angle (T)
				1″	5-6％	18-22％	1-2％
1″	6-7％	20-23％	2-3％
				2″	7-8％	24-28％	2-3％
1″	8-9％	30-33％	2-3％
				3″	9-10％	33-36％	3-4％

In fig. 8-11, the main elements of a shoe made in accordance with other and preferred embodiments of the present invention are shown. The shoe includes a last (insole) plate 110, which is a dimensionally stable flexible material such as leather, fiberboard, non-woollen material, and the like. Below the last plate 110 is an outsole 112 and a heel 114, above the last plate 110 is a rigid device 116, the rigid device 116 including a heel cup 118 and an anatomically shaped dome device 120 extending forward from the heel cup 118 to just behind the metatarsal head region 122. The device 116 is molded and sized to fit the underside of the foot, which allows the wearer's heel to rest and stabilize in the shoe, sloping downward from the heel cup 118, about 5-10 ° depending on the height of the heel, thereby allowing the foot to assume an anatomically correct position in the shoe while the wearer's heel is maintained in a nearly parallel relationship to the base surface, thereby supporting the wearer's phalanges to prevent the wearer's foot from sliding forward relative to the shoe, as described in detail above. Means 116 is glued and/or mechanically riveted or fixed to last (insole) plate 110.

The device 116 may be formed of a lightweight, rigid material compatible with footwear construction. The molding device 116 is therefore preferably formed of ABS plastic, however, the device 116 may be formed of other rigid plastic molding materials or synthetic materials, such as fiber reinforced plastic, or metal, such as aluminum foam. The device 116 serves the dual function of positioning and securing the foot of the wearer in the shoe, supporting the foot in an anatomically correct position and providing torsional balance, and also stiffening the shoe from heel forward to just behind the metatarsal head region and supporting the weight of the user. Thus, a separate reinforcing sole armature may not be required, however, if desired, a reinforcing sole may be incorporated into the footwear. In addition, because the device 116 is an integral part of the shoe, its proper position in the shoe ensures that the position of the wearer's foot in the shoe.

The shoe is also provided with an inner sole or insole 124 which is placed over the moulding 116, and an upper 126 for the shoe. Heel 114 is attached to outsole 112 by adhesive and/or mechanical nailing in a known manner, and upper 126 is secured to the bottom end of last (insole) plate 110 and outsole 112 by stitching, adhesive, staples, rivets or by a combination of a variety of known shoe making techniques.

The present invention may be modified, for example, in that the outsole 112 and heel 114 may be integrally formed as a single unit, as shown in FIG. 9. In addition, as shown in FIG. 12, the device 116 may be advantageously used with a low-heeled shoe 130 or boot. For this application, the device 116 will be tilted slightly downwardly from the heel cup 118 to accommodate the lower heel height, while the heel is maintained in a near parallel relationship with the base surface. In addition, the device 116 can also be adapted for different user applications, such as golf shoes, to provide the desired angle for torsional stability and to anatomically hold the foot in place while maintaining the structural integrity of the shoe. For example, when applied to a golf shoe, region 132 may be tapered longitudinally in the foot's central arch to allow the arch area of the foot to rise or fall during a swing motion, while the central region will maintain a rigid structure to prevent damage to the long axis. The device 116 may also be advantageously used in walking and running shoes, tennis shoes, hiking boots, cross-training shoes, sandals, and other active shoes requiring torsional balance for men and women, as well as for children.

While the invention has been described with reference to a preferred embodiment, various changes may be made therein without departing from the spirit and scope of the invention. For example, as shown in fig. 11, a cut-out region 140 may be removed from the device 116, below the tip 1/3 at about the anterior end of the first metatarsal. The scope of the invention is therefore intended to be limited solely by the scope of the appended claims.

Claims (20)

1. A high-heeled shoe comprising:

a heel having a constant heel height (α) of at least one inch;

a heel seat (20) above said heel;

an arched support (22) extending forwardly from the heel seat and having a first portion for supporting the forward navicular end of the wearer approximately in the same plane as the calcaneus of the wearer relative to the base;

a mid-sole (24) extending forwardly and downwardly from the first portion of the arch support; and

a toe region (26) extending forwardly upwardly and forwardly from the midsection of the sole, thereby supporting the phalanges of the wearer and preventing forward sliding of the wearer's foot relative to the shoe, wherein the heel seat is positioned clockwise relative to the midsection of the sole at an angle "H" which is related to the base surface 18 by the formula:

H=5°+(α×1.25°)

where α = heel height of 1/2 "after exceeding 1". The mid-sole slopes at an angle "M" and stands upright on the base surface according to the following formula:

M=18°+(α×3.25°)

where α = heel height of 1/2 "after exceeding 1".

2. A high-heeled shoe as claimed in claim 1, wherein the heel seat (20) is inclined at an angle of about 3 ° ± 1 ° to the base.

3. The high-heeled shoe of claim 1, wherein said sole (24) is inclined at an angle of about 3 ° ± 3 ° with respect to the base.

4. A high-heeled shoe as claimed in claim 1, wherein the toe region (26) of the shoe is inclined at an angle of about 2-3 ° ± 1 ° relative to the base surface (18).

5. A high-heeled shoe as claimed in claim 1, wherein the heel height (α) is about 1 inch, the heel-seat inclination angle (H) is 5-6 °, the metatarsal angle (M) is 18-22 ° and the toe angle (T) is 1-2 °.

6. The high-heeled shoe of claim 1, wherein the heel height (α) is about 1.vz, the heel base inclination angle (H) is 6-7 °, the metatarsal angle (M) is 20-23 °, and the toe angle (T) is 2-3 °.

7. A high-heeled shoe as claimed in claim 1, wherein the heel height (α) is about 2 inches, the heel-seat inclination angle (H) is 7-8 °, the metatarsal angle (M) is 24-28 ° and the toe angle (T) is 2-3 °.

8. The high-heeled shoe of claim 1, wherein the heel height (α) is about 2.vz inches, the heel base inclination angle (H) is 8-9 °, the metatarsal angle (M) is 30-33 °, and the toe angle (T) is 2-3 °.

9. A high-heeled shoe as claimed in claim 1, wherein the heel height (α) is about 3 inches, the heel-seat inclination angle (H) is 9-10 °, the metatarsal angle (M) is 33-36 ° and the toe angle (T) is 3-4 °.

10. An improved shoe construction comprising: a resilient shoe or insole board (110) overlying an outsole (112) and a heel (114), characterized by:

a stiffening means (116) comprising a heel cup (118) and an anatomically shaped arch means (120) extending from the heel cup forward to just behind the metatarsal head region, the stiffening means (116) being secured to the last plate (110) thereby positioning and stabilizing the wearer's heel in the shoe and allowing the wearer's foot to maintain an anatomically correct position in the shoe and providing torsional stability, the means and providing structural integrity to the shoe.

11. The shoe structure of claim 10 wherein said stiffening means comprises ABS plastic.

12. The improved shoe construction of claim 10 wherein said shoe comprises a high-heeled shoe or boot and said stiffening means comprises a heel cup and anatomically arcuate means to allow the wearer's heel to be in a near parallel relationship with respect to the base.

13. The improved shoe structure of claim 12 wherein said user's heel is maintained in a 5-10 ° relationship with the ground.

14. The shoe construction of claim 10, characterized in that said shoe comprises a golf shoe and that the area of said rigid means (116) underlying the central longitudinal arch of the wearer's foot is thinned relative to other areas of said means so that the arch area of the foot can rise and fall while walking.

15. The shoe structure of claim 10, characterized in that said stiffening means (112) is molded.

16. The shoe structure of claim 10, characterized in that said stiffening means (112) is machined.

17. The shoe construction of claim 10, characterized in that said stiffening means (112) is adhered to said last plate.

18. The shoe structure of claim 10, wherein said stiffening means (112) is mechanically secured to said last plate.

19. The shoe structure of claim 10, characterized in that a cut-out area (140) is provided on said rigid means, below about the distal end 1/3 of the first metatarsal head.

20. A method of making a shoe in which the upper end of the shoe and the outsole are secured to a last plate, comprising attaching a stiffening means comprising a heel cup and an anatomically arched means to the upper end of the last plate prior to final securement of the upper end and/or outsole, thereby stiffening said plate from the heel onwards to the proximal metatarsal heads.