Background of the Invention
[0001] This invention relates to a shoe, such as a street shoe, athletic shoe, and especially
a running shoe with a contoured sole. More particularly, this invention relates to
a novel contoured sole design for a running shoe which improves the inherent stability
and efficient motion of the shod foot in extreme exercise. Still more particularly,
this invention relates to a running shoe wherein the shoe sole conforms to the natural
shape of the foot, particularly the sides, permitting the foot to react naturally
with the ground as it would if the foot were bare, while continuing to protect and
cushion the foot.
[0002] By way of introduction, barefoot populations universally have a very low incidence
of running "overuse" injuries, despite very high activity levels. In contrast, such
injuries are very common in shoe shod populations, even for activity levels well below
"overuse". Thus, it is a continuing problem with a shod population to reduce or eliminate
such injuries and to improve the cushioning and protection for the foot. It is primarily
to an understanding of the reasons for such problems and to proposing a novel solution
according to the invention to which this improved shoe is directed.
[0003] A wide variety of designs are available for running shoes which are intended to provide
stability, but which lead to a constraint in the natural efficient motion of the foot
and ankle. However, such designs which can accommodate free, flexible motion in contrast
create a lack of control or stability. A popular existing shoe design incorporates
an inverted, outwardly-flared shoe sole wherein the ground engaging surface is wider
than the heel engaging portion. However, such shoes are unstable in extreme situations
because the shoe sole, when inverted or on edge, immediately becomes supported only
by the sharp bottom sole edge where the entire weight of the body, multiplied by a
factor of approximately three at running peak, is concentrated. Since an unnatural
lever arm and force moment are created under such conditions, the foot and ankle are
destabilized and, in the extreme, beyond a certain point of rotation about the pivot
point of the shoe sole edge, forcibly cause ankle strain. In contrast, the unshod
foot is always in stable equilibrium without a comparable lever arm or force moment
and, at its maximum range of inversion motion, about 20°, the base of support on the
barefoot heel actually broadens substantially as the calcaneal tuberosity contacts
the ground. This is in contrast to the conventionally available shoe sole bottom which
maintains a sharp, unstable edge.
[0004] Existing running shoes interfere with natural foot and ankle biomechanics, disrupting
natural stability and efficient natural motion. They do so by altering the natural
position of the foot relative to the ground, during the load-bearing phase of running
or walking. The foot in its natural, bare state is in direct contact with the ground,
so its relative distance from the ground is obviously constant at zero. Even when
the foot tilts naturally from side to side, either moderately when running or extremely
when stumbling or tripping, the distance always remains constant at zero.
[0005] In contrast, existing shoes maintain a constant distance from the ground - the thickness
of the shoe sole - only when they are perfectly flat on the ground. As soon as the
shoe is tilted, the distance between foot and ground begins to change unnaturally,
as the shoe sole pivots around the outside comer edge. With conventional athletic
shoes, the distance most typically increases at first due to the flared sides and
then decreases; many street shoes with relatively wide heel width follow that pattern,
though some with narrower heels only decrease. All existing shoes continue to decrease
the distance all the way down to zero, by tilting through 90 degrees, resulting in
ankle sprains and breaks.
[0006] A corrected shoe sole design, however, avoids such unnatural interference by neutrally
maintaining a constant distance between foot and ground, even when the shoe is tilted
sideways, as if in effect the shoe sole were not there except to cushion and protect.
Unlike existing shoes, the corrected shoe would move with the foot's natural sideways
pronation and supination motion on the ground. To the problem of using a shoe sole
to maintain a naturally constant distance during that sideways motion, there are two
possible geometric solutions, depending upon whether just the lower horizontal plane
of the shoe sole surface varies to achieve natural contour or both upper and lower
surface planes vary.
[0007] In the two plane solution, the naturally contoured design, which will be described
in Figures 1-23, both upper and lower surfaces or planes of the shoe sole vary to
conform to the natural contour of the human foot. The two plane solution is the most
fundamental concept and naturally most effective. It is the only pure geometric solution
to the mathematical problem of maintaining constant distance between foot and ground,
and the most optimal, in the same sense that round is only shape for a wheel and perfectly
round is most optimal. On the other hand, it is the least similar to existing designs
of the two possible solutions and requires computer aided design and injection molding
manufacturing techniques.
[0008] U.S. Patent No. 4,305,212 discloses a unitary shoe sole S having a convexly rounded
inner surface 20, relative to a section of the sole directly adjacent to the inner
surface. The shoe sole S also includes rounded portions of the outer surface 21 as
shown in Figs. 8-11. The sole S is integrally formed as one body from a flexible and
resiliently depressible elastomer that is adapted to be distorted by force and to
return to its original form at a predetermined rate. See col. 6, lines 17-29. Fig.
12, a cross-section at the heel area, shows the sole S provided with a circumferential
rib B which establishes an instep cavity C which permits sole deformation to simulate
running in the sand, a key feature of the invention of this patent as discussed with
regard to Fig. 4 and at col. 8, lines 39-44.
[0009] It is thus an overall objective of this invention to provide a novel shoe design
which approximates the barefoot. It has been discovered, by investigating the most
extreme range of ankle motion to near the point of ankle sprain, that the abnormal
motion of an inversion ankle sprain, which is a tilting to the outside or an outward
rotation of the foot, is accurately simulated while stationary. With this observation,
it can be seen that the extreme range stability of the conventionally shod foot is
distinctly inferior to the barefoot and that the shoe itself creates a gross instability
which would otherwise not exist.
[0010] Even more important, a normal barefoot running motion, which approximately includes
a 7° inversion and a 7° eversion motion, does not occur with shod feet, where a 30°
inversion and eversion is common. Such a normal barefoot motion is geometrically unattainable
because the average running shoe heel is approximately 60% larger than the width of
the human heel. As a result, the shoe heel and the human heel cannot pivot together
in a natural manner; rather, the human heel has to pivot within the shoe but is resisted
from doing so by the shoe heel counter, motion control devices, and the lacing and
binding of the shoe upper, as well as various types of anatomical supports interior
to the shoe.
[0011] Thus, it is an overall objective to provide an improved shoe design which is not
based on the inherent contradiction present in current shoe designs which make the
goals of stability and efficient natural motion incompatible and even mutually exclusive.
It is another overall object of the invention to provide a new contour design which
simulates the natural barefoot motion in running and thus avoids the inherent contradictions
in current designs.
[0012] It is an objective of this invention to provide a new stable shoe design wherein
the heel lift or wedge increases the thickness of the shoe sole in the sagittal plane
or toe taper decreases the thickness of the shoe sole in the sagittal plane.
[0013] It is another objective of this invention to provide a shoe having a shoe sole having
a naturally contoured design as described wherein the sides of the shoe sole are abbreviated
to essential structural support and propulsion elements to provide flexibility and
in which the density of the shoe sole may be increased to compensate for increased
loading.
[0014] It is another objective of this invention to provide a shoe sole design which includes
a plurality of freely articulating essential structural support elements in the sole
of the shoe which are consistent with the sole of the foot and are free to move independently
of each other to follow the motion of the freely articulating bone structures of the
foot.
[0015] It is still another object of this invention to provide a shoe sole of the type described
wherein the material of the sole is removed except beneath essential structural support
elements of the foot.
[0016] It is another object of this invention to provide a shoe sole of the type described
with treads having an outer or a base surface which follows the theoretically ideal
stability plane.
[0017] The present invention achieves these objects by providing a shoe sole including a
bottom sole, a midsole which is softer than the bottom sole, and a heel lift. The
sole inner surface includes a portion that is convexly rounded relative to a section
of the shoe sole located directly adjacent to the convexly rounded portion, and the
sole outer surface includes an uppermost portion which extends to at least the height
of the lowest point of the inner surface, both as viewed in a frontal plane cross-section
when the shoe sole is in an upright, unloaded condition. The sole outer surface includes
at least one concavely rounded portion which extends down a sole side to at least
proximate a lowest point of the shoe sole side, the concavity being determined relative
to an inner section of the sole located directly adjacent to the concavely rounded
portion, also as viewed in a frontal plane cross-section when the shoe sole is in
an upright, unloaded condition. The concavely rounded portion of the sole outer surface
includes midsole thereby providing improved stability. The midsole part of the concavely
rounded portion of the outer surface extends below a sidemost extent of the shoe sole
side.
[0018] These and other objectives of the invention will become apparent from a detailed
description of the invention which follows taken in conjunction with the accompanying
drawings.
Brief Description of the Drawings
[0019] In the drawings:
Fig. 1 is a perspective view of a typical running shoe known to the prior art to which
the invention is applicable.
Fig. 2 shows, in Figs. 2A and 2B, the obstructed natural motion of the shoe heel in
frontal planar cross section rotating inwardly or outwardly with the shoe sole having
a flared bottom in a conventional prior art design such as in Fig. 1; and in Figs.
2C and 2D, the efficient motion of a narrow rectangular shoe sole design.
Fig. 3 is a drawn comparison between a conventional flared sole shoe of the prior
art and the contoured shoe sole design according to the invention.
Fig. 4 shows, in Figs. 4A-4C, the extremely stable conditions for the novel shoe sole
according to the invention in its neutral and extreme situations.
Fig. 5 is a side cross-sectional view of the naturally contoured sole side showing
in Fig. 5A how the sole maintains a constant distance from the ground during rotation
of the shoe edge; and showing in Fig. 5B how a conventional shoe sole side cannot
maintain a constant distance from the ground.
Fig. 6 shows, in Figs. 6A-6E, a plurality of side sagittal plane cross-sectional views
showing examples of conventional sole thickness variations to which the invention
can be applied.
Fig. 7 shows, in Figs. 7A-7D, frontal plane cross-sectional views of the shoe sole
according to the invention showing a theoretically ideal stability plane and truncations
of the sole side contour to reduce shoe bulk.
Fig. 8 shows, in Figs. 8A-8C, the contoured sole design according to the invention
when applied to various tread and cleat patterns.
Fig. 9 illustrates, in a rear view, an application of the sole according to the invention
to a shoe to provide an aesthetically pleasing and functionally effective design.
Fig. 10 shows a fully contoured shoe sole design that follows the natural contour
of the bottom of the foot as well as the sides.
Fig. 11 is a diagrammatic frontal plane cross-sectional view of static forces acting
on the ankle joint and its position relative to the shoe sole according to the invention
during normal and extreme inversion and eversion motion.
Fig. 12 is a diagrammatic frontal plane view of a plurality of moment curves of the
center of gravity for various degrees of inversion for the shoe sole according to
the invention, and contrasted to the motions shown in Fig. 2.
Fig. 13 shows, in Figs. 13A and 13B, a rear diagrammatic view of a human heel, as
relating to a conventional shoe sole (Fig. 13A) and to the sole of the invention (Fig.
13B).
Fig. 14 shows the naturally contoured sides design extended to the other natural contours
underneath the load-bearing foot such as the main longitudinal arch.
Fig. 15 illustrates the fully contoured shoe sole design extended to the bottom of
the entire non-load-bearing foot.
Fig. 16 shows the fully contoured shoe sole design abbreviated along the sides to
only essential structural support and propulsion elements.
Fig. 17 shows a method of establishing the theoretically ideal stability plane using
a perpendicular to a tangent method.
Fig. 18 shows a circle radius method of establishing the theoretically ideal stability
plane.
Fig. 19 illustrates an alternate embodiment of the invention wherein the sole structure
deforms in use to follow a theoretically ideal stability plane according to the invention
during deformation.
Fig. 20 shows an embodiment wherein the contour of the sole according to the invention
is approximated by a plurality of line segments.
Fig. 21 shows a shoe sole design that allows for unobstructed natural eversion/inversion
motion by providing torsional flexibility in the instep area of the shoe sole.
Fig. 22 shows several embodiments wherein the bottom sole includes most or all of
the special contours of the new designs and retains a flat upper surface.
Fig. 23 shows, in Figs. 23A - 23C, an enhancement applied to the naturally contoured
sides embodiment of the invention.
Detailed Description of the Preferred Embodiment
[0020] A perspective view of an athletic shoe, such as a typical running shoe, according
to the prior art, is shown in Fig. 1 wherein a running shoe 20 includes an upper 21
and a sole 22. Typically, such a sole includes a truncated outwardly flared construction
of the type best seen in Fig. 2 wherein the lower portion 22a of the sole heel is
significantly wider than the upper portion 22b where the sole 22 joins the upper 21.
A number of alternative sole designs are known to the art, including the design shown
in U.S. Patent No. 4,449,306 to Cavanagh wherein an outer portion of the sole of the
running shoe includes a rounded portion having a radius of curvature of about 20mm.
The rounded portion lies along approximately the rear-half of the length of the outer
side of the midsole and heel edge areas wherein the remaining border area is provided
with a conventional flaring with the exception of a transition zone. The U.S. Patent
to Misevich, No. 4,557,059, also shows an athletic shoe having a contoured sole bottom
in the region of the first foot strike, in a shoe which otherwise uses an inverted
flared sole.
[0021] In such prior art designs, and especially in athletic and in running shoes, the typical
design attempts to achieve stability by flaring the heel as shown in Figs. 2A and
2B to a width of, for example, 3 to 3-1/2 inches on the lower portion 22a of the sole
heel of the average male shoe size (10D). On the other hand, the width of the corresponding
human heel foot print, housed in the upper 21, is only about 2.25 in. for the average
foot. Therefore, a mismatch occurs in that the heel is locked by the design into a
firm shoe heel counter which supports the human heel by holding it tightly and which
may also be reinforced by motion control devices to stabilize the heel. Thus, for
natural motion as is shown in Figs. 2A and 2B, the human heel would normally move
in a normal range of motion of approximately 15°, but as shown in Figs. 2A and 2B
the human heel cannot pivot except within the shoe and is resisted by the shoe. Thus,
Fig. 2A illustrates the impossibility of pivoting about the center edge of the human
heel as would be conventional for barefoot support about a point 23 defined by a line
23a perpendicular to the heel and intersecting the bottom edge of upper 21 at a point
24. The lever arm force moment of the flared sole is at a maximum at 0° and only slightly
less at a normal 7° inversion or eversion and thus strongly resists such a natural
motion as is illustrated in Figs. 2A and 2B. In Fig. 2A, the outer edge of the heel
must compress to accommodate such motion. Fig. 2B illustrates that normal natural
motion of the shoe is inefficient in that the center of gravity of the shoe, and the
shod foot, is forced upwardly, as discussed later in connection with Fig. 12.
[0022] A narrow rectangular shoe sole design of heel width approximating human heel width
is also known and is shown in Figs. 2C and 2D. It appears to be more efficient than
the conventional flared sole shown in Figs. 2A and 2B. Since the shoe sole width is
the same as human sole width, the shoe can pivot naturally with the normal 7° inversion/eversion
motion of the running barefoot. In such a design, the lever arm length and the vertical
motion of the center of gravity are approximately half that of the flared sole at
a normal 7° inversion/eversion running motion. However, the narrow, human heel width
rectangular shoe design is extremely unstable and therefore prone to ankle sprain,
so that it has not been well received. Thus, neither of these wide or narrow designs
is satisfactory.
[0023] The shoe sole thickness is defined as the shortest distance (s) between any point
on the inner surface 30 of the shoe sole 28 and the outer surface 31 (Figs. 17 and
18 will discuss measurement methods more fully).
[0024] Fig. 3 thus contrasts in frontal plane cross section the conventional flared sole
22 shown in phantom outline and illustrated in Fig. 2 with the contoured shoe sole
28 according to the invention.
[0025] Fig. 4 is suitable for analyzing the shoe sole design according to the applicant's
invention by contrasting the neutral situation shown in Fig. 4A with the extreme situations
shown in Figs. 4B and 4C. Unlike the sharp sole edge of a conventional shoe as shown
in Fig. 2, the effect of the applicant's invention having a naturally contoured side
28a is totally neutral allowing the shod foot to react naturally with the ground 43,
in either an inversion or eversion mode. This occurs in part because of the unvarying
thickness along the shoe sole edge which keeps the foot sole equidistant from the
ground in a preferred case. Moreover, because the shape of the edge 31a of the shoe
contoured side 28a is exactly like that of the edge of the foot, the shoe is enabled
to react naturally with the ground in a manner as closely as possible simulating the
foot. Thus, in the neutral position shown in Fig. 4, any point 40 on the surface of
the shoe sole 30b closest to ground lies at a distance (s) from the ground surface
43. That distance (s) remains constant even for extreme situations as seen in Figs.
4B and 4C.
[0026] A main point of the applicant's invention, as is illustrated in Figs. 4B and 4C,
is that the design shown is stable in an
in extremis situation. The theoretically ideal plane of stability is where the stability plane
is defined as sole thickness which is constant under all load-bearing points of the
foot sole for any amount from 0° to 90° rotation of the sole to either side or front
and back. In other words, as shown in Fig. 4, if the shoe is tilted from 0° to 90°
to either side or from 0° to 90° forward or backward representing a 0° to 90° foot
dorsiflexion or 0° to 90° plantarflexion, the foot will remain stable because the
sole thickness (s) between the foot and the ground always remain constant because
of the exactly contoured quadrant sides. By remaining a constant distance from the
ground, the stable shoe allows the foot to react to the ground as if the foot were
bare while allowing the foot to be protected and cushioned by the shoe. In its preferred
embodiment, the new naturally contoured sides will effectively position and hold the
foot onto the load-bearing foot print section of the shoe sole, reducing or eliminating
the need for heel counters and other relatively rigid motion control devices.
[0027] Fig. 5A illustrates how the inner edge 30a of the naturally contoured sole side 28a
is maintained at a constant distance (s) from the ground through various degrees of
rotation of the edge 31a of the shoe sole such as is shown in Fig. 4. Figure 5B shows
how a conventional shoe sole pivots around its lower edge 42, which is its center
of rotation, instead of around the upper edge 41, which, as a result, is not maintained
at constant distance (s) from the ground, as with the invention, but is lowered to
.7(s) at 45° rotation and to zero at 90° rotation.
[0028] Fig. 6 shows typical conventional sagittal plane shoe sole thickness variations,
such as heel lifts or wedges 38, or toe taper 38a, or full sole taper 38b, in Figs.
6A-6E and how the naturally contoured sides 28a equal and therefore vary with those
varying thicknesses. As shown in Fig. 6A, heel lift 38 has a thickness (s
1) in the heel area to increase the sole thickness to (s + s
1). In the midtarsal area, heel lift 38 has a decreased thickness (s
2).
[0029] Fig. 7 illustrates an embodiment of the invention which utilizes varying portions
of the theoretically ideal stability plane 51 in the naturally contoured sides 28a
in order to reduce the weight and bulk of the sole, while accepting a sacrifice in
some stability of the shoe. Thus, Fig. 7A illustrates the preferred embodiment wherein
the outer edge 31a of the naturally contoured sides 28a follows a theoretically ideal
stability plane 51. The outer edge 31 a and the outer surface of the sole 31b lie
along the theoretically ideal stability plane 51. The theoretically ideal stability
plane 51 is defined as the plane of the outer surface 31 of the shoe sole 28, wherein
the shoe sole conforms to the natural shape of the foot, particularly the sides, and
has a constant thickness in frontal plane cross sections. As shown in Fig. 7B, an
engineering trade-off results in an abbreviation within the theoretically ideal stability
plane 51 by forming a naturally contoured upper side surface 53a approximating the
natural contour of the foot (or more geometrically regular, which is less preferred)
at an angle relative to the upper plane of the shoe sole 28 so that only a smaller
portion of the contoured side 28a defined by the constant thickness lying along the
surface 31a is coplanar with the theoretically ideal stability plane 51. Figs. 7C
and 7D show similar embodiments wherein each engineering trade-off shown results in
progressively smaller portions of contoured side 28a, which lies along the theoretically
ideal stability plane 51. The portion of the surface 31a merges into the upper side
surface 53a of the naturally contoured side.
[0030] The embodiment of Fig. 7 may be desirable for portions of the shoe sole which are
less frequently used so that the additional part of the side is used less frequently.
For example, a shoe may typically roll out laterally, in an inversion mode, to about
20° on the order of 100 times for each single time it rolls out to 40°. For a basketball
shoe, shown in Fig. 7B, the extra stability is needed. Yet, the added shoe weight
to cover that infrequently experienced range of motion is about equivalent to covering
the frequently encountered range. Since, in a racing shoe this weight might not be
desirable, an engineering trade-off of the type shown in Fig. 7D is possible. A typical
running/jogging shoe is shown in Fig. 7C. The range of possible variations is limitless.
[0031] Fig. 8 shows the theoretically ideal stability plane 51 in defining embodiments of
the shoe sole having differing tread or cleat patterns. Thus, Fig. 8 illustrates that
the invention is applicable to shoe soles having conventional bottom treads. Accordingly,
Fig. 8A is similar to Fig. 7B further including a tread portion 60, while Fig. 8B
is also similar to Fig. 7B wherein the sole includes a cleated portion 61. The surface
63 to which the cleat bases are affixed should preferably be on the same plane and
parallel the theoretically ideal stability plane 51, since in soft ground that surface
rather than the cleats become load-bearing. The embodiment in Fig. 8C is similar to
Fig. 7C showing still an alternative tread construction 62. In each case, the load-bearing
outer surface of the tread or cleat pattern 60-62 lies along the theoretically ideal
stability plane 51.
[0032] Fig. 9 shows, in a rear cross sectional view, the application of the invention to
a shoe to produce an aesthetically pleasing and functionally effective design. Thus,
a practical design of a shoe incorporating the invention is feasible, even when applied
to shoes incorporating heel lifts 38 and a combined midsole and outersole 39. Thus,
use of a sole surface and sole outer contour which track the theoretically ideal stability
plane does not detract from the commercial appeal of shoes incorporating the invention.
[0033] Fig. 10 shows a fully contoured shoe sole design that follows the natural contour
of all of the foot, the bottom as well as the sides. The fully contoured shoe sole
assumes that the resulting slightly rounded bottom when unloaded will deform under
load and flatten just as the human foot bottom is slightly rounded unloaded but flattens
under load; therefore, shoe sole material must be of such composition as to allow
the natural deformation following that of the foot. The design applies particularly
to the heel, but to the rest of the shoe sole as well. By providing the closest match
to the natural shape of the foot, the fully contoured design allows the foot to function
as naturally as possible. Under load, Fig. 10 would deform by flattening to look essentially
like Fig. 9. Seen in this light, the naturally contoured side design in Fig. 9 is
a more conventional, conservative design that is a special case of the more general
fully contoured design in Fig. 10, which is the closest to the natural form of the
foot, but the least conventional. The amount of deformation flattening used in the
Fig. 9 design, which obviously varies under different loads, is not an essential element
of the applicant's invention.
[0034] Figs. 9 and 10 both show in frontal plane cross section the essential concept underlying
this invention, the theoretically ideal stability plane, which is also theoretically
ideal for efficient natural motion of all kinds, including running, jogging or walking.
Fig. 10 shows the most general case of the invention, the fully contoured design,
which conforms to the natural shape of the unloaded foot. For any given individual,
the theoretically ideal stability plane 51 is determined, first, by the desired shoe
sole thickness (s) in a frontal plane cross section, and, second, by the natural shape
of the individual's foot surface 29.
[0035] For the special case shown in Fig. 9, the theoretically ideal stability plane for
any particular individual (or size average of individuals) is determined, first, by
the given frontal plane cross section shoe sole thickness (s); second, by the natural
shape of the individual's foot; and, third, by the frontal plane cross section width
of the individual's load-bearing footprint, which is defined as the upper surface
of the shoe sole that is in physical contact with and supports the human foot sole.
[0036] The theoretically ideal stability plane for the special case is composed conceptually
of two parts. Shown in Fig. 9, the first part is a line segment 31b of equal length
and parallel to 30b at a constant distance (s) equal to shoe sole thickness. This
corresponds to a conventional shoe sole directly underneath the human foot, and also
corresponds to the flattened portion of the bottom of the load-bearing foot sole 28b.
The second part is the naturally contoured stability side outer edge 31a located at
each side of the first part, line segment 31b. Each point on the contoured side outer
edge 31a is located at a distance which is exactly shoe sole thickness (s) from the
closest point on the contoured side inner edge 30a.
[0037] Fig. 11 illustrates in a curve 70 the range of side to side inversion/eversion motion
of the ankle center of gravity 71 from the shoe according to the invention shown in
frontal plane cross section at the ankle. Thus, in a static case where the center
of gravity 71 lies at approximately the mid-point of the sole, and assuming that the
shoe inverts or everts from 0° to 20° to 40°, as shown in progressions 16A, 16B and
16C, the locus of points of motion for the center of gravity 71 thus defines the curve
70 wherein the center of gravity 71 maintains a steady level motion with no vertical
component through 40° of inversion or eversion. For the embodiment shown, the shoe
sole stability equilibrium point is at 28° (at point 74) and in no case is there a
pivoting edge to define a rotation point as in the case of Fig. 2. The inherently
superior side to side stability of the design provides pronation control (or eversion),
as well as lateral (or inversion) control. In marked contrast to conventional shoe
sole designs, the applicant's shoe design creates virtually no abnormal torque to
resist natural inversion/eversion motion or to destabilize the ankle joint.
[0038] Fig. 12 thus compares the range of motion of the center of gravity for the invention,
as shown in curve 70, in comparison to curve 80 for the conventional wide heel flare
and a curve 82 for a narrow rectangle the width of a human heel. Since the shoe stability
limit is 28° in the inverted mode, the shoe sole is stable at the 20° approximate
barefoot inversion limit. That factor, and the broad base of support rather than the
sharp bottom edge of the prior art, make the contour design stable even in the most
extreme case as shown in progressions 16A-16C and permit the inherent stability of
the barefoot to dominate without interference, unlike existing designs, by providing
constant, unvarying shoe sole thickness in frontal plane cross sections. The stability
superiority of the contoured side design is thus clear when observing how much flatter
its center of gravity curve 70 is than in existing popular wide flare design 80. The
curve 70 demonstrates that the contoured side design has significantly more efficient
natural 7° inversion/eversion motion than the narrow rectangle design 82 the width
of a human heel, and very much more efficient than the conventional wide flare design
80; at the same time, the contoured side design is more stable
in extremis than either conventional design because of the absence of destabilizing torque.
[0039] Fig. 13A illustrates, in a pictorial fashion, a comparison of a cross section at
the ankle joint of a conventional shoe with a cross section of a shoe according to
the invention when engaging a heel. As seen in Fig. 13A, when the heel of the foot
27 of the wearer engages an upper surface of the shoe sole 22, the shape of the foot
heel and the shoe sole is such that the conventional shoe sole 22 conforms to the
contour of the ground 43 and not to the contour of the sides of the foot 27. As a
result, the conventional shoe sole 22 cannot follow the natural 7° inversion/eversion
motion of the foot, and that normal motion is resisted by the shoe upper 21, especially
when strongly reinforced by firm heel counters and motion control devices. This interference
with natural motion represents the fundamental misconception of the currently available
designs. That misconception on which existing shoe designs are based is that, while
shoe uppers are considered as a part of the foot and conform to the shape of the foot,
the shoe sole is functionally conceived of as a part of the ground and is therefore
shaped like the ground, rather than the foot.
[0040] In contrast, the new design, as illustrated in Fig. 13B, illustrates a correct conception
of the shoe sole 28 as a part of the foot and an extension of the foot, with shoe
sole sides contoured exactly like those of the foot, and with the frontal plane thickness
of the shoe sole between the foot and the ground always the same and therefore completely
neutral to the natural motion of the foot. With the correct basic conception, as described
in connection with this invention, the shoe can move naturally with the foot, instead
of restraining it, so both natural stability and natural efficient motion coexist
in the same shoe, with no inherent contradiction in design goals.
[0041] Thus, the contoured shoe design of the invention brings together in one shoe design
the cushioning and protection typical of modem shoes, with the freedom from injury
and functional efficiency, meaning speed, and/or endurance, typical of barefoot stability
and natural freedom of motion. Significant speed and endurance improvements are anticipated,
based on both improved efficiency and on the ability of a user to train harder without
injury.
[0042] These figures also illustrate that the shoe heel cannot pivot plus or minus 7 degrees
with the prior art shoe of Fig. 13A. In contrast, the shoe heel in the embodiment
of Fig. 13B pivots with the natural motion of the foot heel.
[0043] Figs. 14A-D illustrate, in frontal plane cross sections, the naturally contoured
sides design extended to the other natural contours underneath the load-bearing foot,
such as the main longitudinal arch, the metatarsal (or forefoot) arch, and the ridge
between the heads of the metatarsals (forefoot) and the heads of the distal phalanges
(toes). As shown, the shoe sole thickness remains constant as the contour of the shoe
sole follows that of the sides and bottom of the load-bearing foot. Fig. 14E shows
a sagittal plane cross section of the shoe sole conforming to the contour of the bottom
of the load-bearing foot, with thickness varying according to the heel lift 38. Fig.
14F shows a horizontal plane top view of the left foot that shows the areas 85 of
the shoe sole that correspond to the flattened portions of the foot sole that are
in contact with the ground when load-bearing. Contour lines 86 and 87 show approximately
the relative height of the shoe sole contours above the flattened load-bearing areas
85 but within roughly the peripheral extent 35 of the upper surface 30 of sole 28.
A horizontal plane bottom view (not shown) of Fig. 14F would be the exact reciprocal
or converse of Fig. 14F (i.e. peaks and valleys contours would be exactly reversed).
[0044] Figs. 15A-D show, in frontal plane cross sections, the fully contoured shoe sole
design extended to the bottom of the entire non-load-bearing foot 27. Fig. 15C shows
that in the midtarsal area, the sole 28 may include a concavely rounded outer surface
portion on only one of the lateral and medial sole sides which does not extend to
the middle portion of the sole 28. Fig. 15E shows a sagittal plane cross section.
The shoe sole contours underneath the foot 27 are the same as Figs. 14A-E except that
there are no flattened areas 85 corresponding to the flattened areas of the load-bearing
foot 27. The exclusively rounded contours of the shoe sole follow those of the unloaded
foot 27. A heel lift 38, the same as that of Fig. 14, is incorporated in this embodiment,
but is not shown in Fig. 15.
[0045] Fig. 16 shows the horizontal plane top view of the left foot corresponding to the
fully contoured design described in Figs. 15A-E, but abbreviated along the sides to
only essential structural support and propulsion elements. Shoe sole material density
can be increased in the unabbreviated essential elements to compensate for increased
pressure loading there. The essential structural support elements are the base and
lateral tuberosity of the calcaneus 95, the heads of the first and fifth metatarsals
96, and the base of the fifth metatarsal 97. They must be supported both underneath
and to the outside for stability. The essential propulsion element is the head of
first distal phalange 98. As shown in Figs. 15-16, the sole 28 can include concavely
rounded portions 95a, 95b, 95c and 95d at the base and lateral tuberosity of the calcaneus
95, concavely rounded portions 96c, 96d, 96e and 96g at the heads of the first and
fifth metatarsals 96, and concavely rounded portions 98, 98a at the head of the first
distal phalange 98. As shown in Fig. 15, the sole 28 can include an indentation 96h
in the middle portion of the forefoot area as well as an indentation 96f in the forefoot
area. Fig. 16 also shows that the thickness of the sole (28) at the concavely rounded
portions 95b, 95c, 96d, 96e and 98 decreases gradually, as viewed in a horizontal
plane, to form areas of lesser sole thickness 95e, 95f, 96a, 96b, 97a and 98a. As
seen in Fig. 16, the concavely rounded portions of the shoe sole 28 may extend to
the front 44 and the rear 45 of the shoe sole 28.
[0046] As shown in Fig. 15E, shoe sole 28 may also include concavely rounded portions, as
viewed in a sagittal plane cross-section and one concavely rounded portion may extend
through a lowermost heel area 28". Also, the thickness of shoe sole 28 may remain
constant from the lowermost heel area 28" to a rearmost heel extent 34 and then decrease
gradually and continuously at an upper rear heel portion 46, all as viewed in a sagittal
plane cross-section.
[0047] The medial (inside) and lateral (outside) sides supporting the base of the calcaneus
are shown in Fig. 16 oriented roughly along either side of the horizontal plane subtalar
ankle joint axis, but can be located also more conventionally along the longitudinal
axis of the shoe sole. Fig. 16 shows that the naturally contoured stability sides
need not be used except in the identified essential areas. Weight savings and flexibility
improvements can be made by omitting the non-essential stability sides. Contour lines
86 through 89 show approximately the relative height of the shoe sole contours within
roughly the peripheral extent 35 of the undeformed inner surface 30 of shoe sole 28.
A horizontal plane bottom view (not shown) of Fig. 16 would be the exact reciprocal
or converse of Fig. 16 (i.e. peaks and valleys contours would be exactly reversed).
[0048] Fig. 17 shows a method of measuring shoe sole thickness to be used to construct the
theoretically ideal stability plane of the naturally contoured side design. The constant
shoe sole thickness of this design is measured at any point p1, p2 on the contoured
sides along a line that, first, is perpendicular to a line tangent to that point on
the surface of the naturally contoured side of the foot sole and, second, that passes
through the same foot sole surface point.
[0049] Fig. 18 illustrates another approach to constructing the theoretically ideal stability
plane, and one that is easier to use, the circle radius method. By that method, the
pivot point (circle center) of a compass is placed at the beginning of the foot sole's
natural side contour (frontal plane cross section) and roughly a 90° arc (or much
less, if estimated accurately) of a circle of radius equal to (s) or shoe sole thickness
is drawn describing the area farthest away from the foot sole contour. That process
is repeated all along the foot sole's natural side contour at very small intervals
(the smaller, the more accurate). When all the circle sections are drawn, the outer
edge farthest from the foot sole contour (again, frontal plane cross section) is established
at a distance of "s" and that outer edge coincides with the theoretically ideal stability
plane. Both this method and that described in Fig. 17 would be used for both manual
and CAD/CAM design applications.
[0050] The shoe sole according to the invention can be made by approximating the contours,
as indicated in Figs. 19A and 19B. Fig. 19A shows a frontal plane cross section of
a design wherein the sole material in areas 107 is so relatively soft that it deforms
easily to the contour of shoe sole 28 of the proposed invention. In the proposed approximation
as seen in Fig. 19B, the heel cross section includes a sole upper surface 101 and
a bottom sole edge surface 102 following when deformed an inset theoretically ideal
stability plane 51. The sole edge surface 102 terminates in a laterally extending
portion 103 joined to the heel of the sole 28. The laterally-extending portion 103
is made from a flexible material and structured to cause its lower surface 102 to
terminate during deformation to parallel the inset theoretically ideal stability plane
51. Sole material in specific areas 107 is extremely soft to allow sufficient deformation.
Thus, in a dynamic case, the outer edge contour assumes approximately the theoretically
ideal stability shape described above as a result of the deformation of the portion
103. The top surface 101 similarly deforms to approximately parallel the natural contour
of the foot as described by surfaces 30a and 30b.
[0051] It is presently contemplated that the controlled or programmed deformation can be
provided by either of two techniques. In one, the shoe sole sides, at especially the
midsole, can be cut in a tapered fashion or grooved so that the bottom sole bends
inwardly under pressure to the correct contour. The second uses an easily deformable
material 107 in a tapered manner on the sides to deform under pressure to the correct
contour. While such techniques produce stability and natural motion results which
are a significant improvement over conventional designs, they are inherently inferior
to contours produced by simple geometric shaping. First, the actual deformation must
be produced by pressure which is unnatural and does not occur with a bare foot and
second, only approximations are possible by deformation, even with sophisticated design
and manufacturing techniques, given an individual's particular running gait or body
weight. Thus, the deformation process is limited to a minor effort to correct the
contours from surfaces approximating the ideal curve in the first instance.
[0052] The theoretically ideal stability plane can also be approximated by a plurality of
line segments 110, such as tangents, chords, or other lines, as shown in Fig. 20.
Both the upper surface of the shoe sole 28, which coincides with the side of the foot
30a, and the bottom surface 31a of the naturally contoured side can be approximated.
While a single flat plane 110 approximation may correct many of the biomechanical
problems occurring with existing designs, because it can provide a gross approximation
of the both natural contour of the foot and the theoretically ideal stability plane
51, the single plane approximation is presently not preferred, since it is the least
optimal. By increasing the number of flat planar surfaces formed, the curve more closely
approximates the ideal exact design contours, as previously described. Single and
double plane approximations are shown as line segments in the cross section illustrated
in Fig. 20.
[0053] Fig. 21 shows a shoe sole design that allows for unobstructed natural inversion/eversion
motion of the calcaneus by providing maximum shoe sole flexibility particularly between
the base of the calcaneus 125 (heel) and the metatarsal heads 126 (forefoot) along
an axis 120. An unnatural torsion occurs about that axis if flexibility is insufficient
so that a conventional shoe sole interferes with the inversion/eversion motion by
restraining it. The object of the design is to allow the relatively more mobile (in
eversion and inversion) calcaneus to articulate freely and independently from the
relatively more fixed forefoot, instead of the fixed or fused structure or lack of
stable structure between the two in conventional designs. In a sense, freely articulating
joints are created in the shoe sole that parallel those of the foot. The design is
to remove nearly all of the shoe sole material between the heel and the forefoot,
except under one of the previously described essential structural support elements,
the base of the fifth metatarsal 97. An optional support for the main longitudinal
arch 121 may also be retained for runners with substantial foot pronation, although
would not be necessary for many runners. The forefoot can be subdivided (not shown)
into its component essential structural support and propulsion elements, the individual
heads of the metatarsal and the heads of the distal phalanges, so that each major
articulating joint set of the foot is paralleled by a freely articulating shoe sole
support propulsion element, an anthropomorphic design; various aggregations of the
subdivisions are also possible. An added benefit of the design is to provide better
flexibility along axis 122 for the forefoot during the toe-off propulsive phase of
the running stride, even in the absence of any other embodiments of the applicant's
invention; that is, the benefit exists for conventional shoe sole designs.
[0054] Fig. 21A shows in sagittal plane cross section a specific design maximizing flexibility,
with large non-essential sections removed for flexibility and connected by only a
top layer (horizontal plane) of non-stretching fabric 123 like Dacron polyester or
Kevlar. Fig. 21B shows another specific design with a thin top sole layer 124 instead
of fabric and a different structure for the flexibility sections: a design variation
that provides greater structural support, but less flexibility, though still much
more than conventional designs. Not shown is a simple, minimalist approach, which
is comprised of single frontal plane slits in the shoe sole material (all layers or
part): the first midway between the base of the calcaneus and the base of the fifth
metatarsal, and the second midway between that base and the metatarsal heads. Fig.
21C shows a bottom view (horizontal plane) of the inversion/eversion flexibility design.
[0055] It is presently contemplated that the controlled or programmed deformation can be
provided by either of two techniques. In one, the shoe sole sides, at especially the
midsole, can be cut in a tapered fashion or grooved so that the bottom sole bends
inwardly under pressure to the correct contour. The second uses an easily deformable
material in a tapered manner on the sides to deform under pressure to the correct
contour. While such techniques produce stability and natural motion results which
are a significant improvement over conventional designs, they are inherently inferior
to contours produced by simple geometric shaping. First, the actual deformation must
be produced by pressure which is unnatural and does not occur with a bare foot and
second, only approximations are possible by deformation, even with sophisticated design
and manufacturing techniques, given an individual's particular running gait or body
weight. Thus, the deformation process is limited to a minor effort to correct the
contours from surfaces approximating the ideal curve in the first instance.
[0056] Fig. 22 shows a non-optimal but interim or low cost approach to shoe sole construction,
whereby the midsole and heel lift 127 are produced conventionally, or nearly so (at
least leaving the midsole bottom surface flat, though the sides can be contoured),
while the bottom or outer sole 128 includes most or all of the special contours 25
of the new design which, as shown in Fig. 22A, extend to a lowest point (28') of a
lowermost side section of the outer surface 31. Not only would that completely or
mostly limit the special contours 25 to the bottom sole 128, which would be molded
specially, it would also ease assembly, since two flat surfaces of the bottom of the
midsole 127 and the top of the bottom sole 128 could be mated together with less difficulty
than two contoured surfaces, as would be the case otherwise. The advantage of this
approach is seen in the naturally contoured design example illustrated in Fig. 22A,
which shows some contours on the relatively softer midsole sides which extend to and
through the sidemost extent 28a' of the sole side and form an uppermost portion 53a'
of upper side surface 53a, which are subject to less wear but benefit from greater
traction for stability and ease of deformation, while the relatively harder contoured
bottom sole 128 provides good wear for the load-bearing areas. As shown in Fig. 22A,
the uppermost section 54 of midsole 127 extends to and above the height of a lowest
point 30' of the same sole side to an uppermost extent 54' of midsole 127. The contours
on the sides form a concavely rounded portion of the outer surface 31, the concavity
being relative to an inner section of the sole 28 directly adjacent to the concavely
rounded portion, and a convexly rounded portion of inner surface 30, the convexity
being determined relative to a section of the sole 28 directly adjacent to the convexly
rounded portion of the inner surface 30. The portion of sole 28 bounded by the convexly
rounded inner surface portion and the concavely rounded outer surface portion is concavely
rounded relative to an intended wearer's foot location inside the shoe, all as shown
in Fig. 22A.
[0057] Also shown in Fig. 22A is that the shoe sole 28 includes a sidemost lateral section
58 located outside a vertical line 59 at the sidemost extent 30" of the lateral side
of the inner surface 30 of the shoe sole 28, and a sidemost medial section 48 located
outside a vertical line 49 of the sidemost extent 30" of the medial side of the inner
surface 30 of the shoe sole 28. The midsole 127 extends into the sidemost lateral
and medial sections 58, 48, as shown.
[0058] Fig. 22B shows in a quadrant side design the concept applied to conventional street
shoe heels, which are usually separated from the forefoot by a hollow instep area
under the main longitudinal arch. Fig. 22C shows in frontal plane cross section the
concept applied to the quadrant sided or single plane design and indicating in Fig.
22D in the shaded area 129 of the bottom sole 128 that portion which should be honeycombed
(axis on the horizontal plane) to reduce the density of the relatively hard outer
sole 128 to that of the midsole material to provide for relatively uniform shoe density.
Fig. 22E shows in bottom view the outline 36 of a bottom sole 128 made from flat material
which can be conformed topologically to a contoured midsole of either the one or two
plane designs by limiting the side areas to be mated to the essential support areas
discussed in Fig. 16; by that method, the contoured midsole and flat bottom sole surfaces
can be made to join satisfactorily by coinciding closely, which would be topologically
impossible if all of the side areas were retained on the bottom sole 128.
[0059] Figs. 23A-23C, frontal plane cross sections, illustrate the inner shoe sole stability
sides enhancement. The enhancement positions and stabilizes the foot relative to the
shoe sole 28, and maintains the constant shoe sole thickness (s) of the naturally
contoured sides 28a design, as shown in Figs. 23B and 23C; Fig. 23A shows a conventional
design. The inner shoe sole stability sides 131 conform to the natural contour of
the foot sides 29, which determine the theoretically ideal stability plane 51 for
the shoe sole thickness (s).
[0060] Thus, it will clearly be understood by those skilled in the art that the foregoing
description has been made in terms of the preferred embodiment and various changes
and modifications may be made without departing from the scope of the present invention
which is to be defined by the appended claims.
1. A shoe sole (28) for a shoe, including:
a bottom sole (128);
a midsole (127) which is softer than the bottom sole (128);
a heel lift (127);
an inner surface (30) including at least one portion that is convexly rounded relative
to a section of the shoe sole (28) located directly adjacent to the convexly rounded
portion of the inner surface (30), as viewed in a frontal plane cross-section, when
the shoe sole (28) is in an upright, unloaded condition;
an outer surface (31) having an uppermost portion (53a') which extends to at least
the height of the lowest point (30') of the inner surface (30), as viewed in a frontal
plane cross-section when the shoe sole (28) is in an upright, unloaded condition;
characterized in that:
the outer surface (31) includes at least one concavely rounded portion which extends
down at least one side of the shoe sole (28) to at least proximate a lowest point
(28') of the shoe sole side, the concavity of the concavely rounded portion of the
outer surface (31) is determined relative to an inner section of the shoe sole (28)
located directly adjacent to the concavely rounded portion of the outer surface (31),
as viewed in a frontal plane cross-section, when the shoe sole (28) is in an upright,
unloaded condition; and
wherein the concavely rounded portion of the outer surface (31) of the side of the
shoe sole (28) includes a part formed by midsole (127), and the midsole part of the
concavely rounded portion of the outer surface (31) extends below a sidemost extent
(28a') of the shoe sole side so that the rounded portion of the shoe sole side deforms
to flatten easily under a wearer's body weight load during sideways motion of the
shoe sole (28), thereby providing improved lateral stability,.
2. A shoe sole (28) as claimed in claim 1, wherein the at least one concavely rounded
portion of the outer surface (31) is located at one or more locations on the shoe
sole (28) proximate to the locations of one or more of the following parts of an intended
wearer's foot when inside the shoe: the base of the calcaneus (95), the lateral tuberosity
of the calcaneus (95), the base of the fifth metatarsal (97), the head of the fifth
metatarsal (96), the head of the first metatarsal (96), and the head of the first
distal phalange (98).
3. The shoe sole (28) of any one of claims 1-2, wherein:
the concavely rounded portion of the outer surface (31) extends up at least one
shoe sole side to a location on the shoe sole side proximate to a sidemost extent
(28a') of the shoe sole side, as viewed in a frontal plane cross-section when the
shoe sole (28) is in an upright, unloaded condition.
4. The shoe sole (28) of any one of claims 1-2, wherein:
the concavely rounded portion of the outer surface (31) extends up at least one
shoe sole side through a sidemost extent (28a') of the shoe sole side, as viewed in
a frontal plane cross-section when the shoe sole (28) is in an upright, unloaded condition.
5. The shoe sole (28) of any one of claims 1-4, wherein:
at least a lowermost part of the concavely rounded portion of the outer surface
(31) is formed by bottom sole (128).
6. The shoe sole (28) of any one of claims 1-5, wherein:
at least a part of a bottom surface of the midsole (127) and at least a part of
a top surface of the bottom sole (128) are substantially flat, as viewed in the frontal
plane cross-section when the shoe sole (28) is in an upright, unloaded condition.
7. The shoe sole (28) of any one of claims 1-6, wherein:
the concavely rounded midsole part of the outer surface (31) is located at least
at a location on the shoe sole (28) proximate to the location of the base of the calcaneus
(95) of an intended wearer's foot when inside the shoe.
8. The shoe sole (28) of any one of claims 1-7, wherein:
the concavely rounded midsole part of the outer surface (31) is located at least
at a location on the shoe sole (28) proximate to the location of the lateral tuberosity
of the calcaneus (95) of an intended wearer's foot when inside the shoe.
9. The shoe sole (28) of any one of claims 1-8, wherein:
the concavely rounded midsole part of the outer surface (31) is located at least
at a location on the shoe sole (28) proximate to the location of the base of the fifth
metatarsal (97) of an intended wearer's foot when inside the shoe.
10. The shoe sole (28) of any one of claims 1-9, wherein:
the concavely rounded midsole part of the outer surface (31) is located at least
at a location on the shoe sole (28) proximate to the location of the head of the fifth
metatarsal (96) of an intended wearer's foot when inside the shoe.
11. The shoe sole (28) of any one of claims 1-10, wherein:
the concavely rounded midsole part of the outer surface (31) is located at least
at a location on the shoe sole (28) proximate to the location of the head of the first
metatarsal (96) of an intended wearer's foot when inside the shoe.
12. The shoe sole (28) of any one of claims 1-11, wherein:
the concavely rounded midsole part of the outer surface (31) is located at least
at a location on the shoe sole (28) proximate to the location of the head of the first
distal phalange (98) of an intended wearer's foot when inside the shoe.
13. The shoe sole (28) of any one of claims 1-12, wherein the shoe sole (28) includes
at least two concavely rounded portions of the outer surface (31) each including midsole
(127) and which are located on opposing sides of the shoe sole (28), as viewed in
a frontal plane cross-section when the shoe sole (28) is in an upright, unloaded condition.
14. The shoe sole (28) of any one of claims 1-6 and claim 13 when dependent from any one
of claims 1-6, wherein the frontal plane cross-section is located in the heel area.
15. The shoe sole (28) of any one of claims 1-14, wherein the thickness of the shoe sole
(28) decreases gradually from a sole thickness at least at one of the concavely rounded
portions of the outer surface (31) of the shoe sole (28) to a lesser sole thickness
on the side of the concavely rounded portion of the outer surface (31), as viewed
in a horizontal plane, to thereby provide torsional flexibility and weight savings
to the shoe sole (28).
16. A shoe sole (28) as claimed in claim 15 wherein the thickness of the shoe sole (28)
decreases gradually on both sides of the concavely rounded portion of the outer surface
(31), as viewed in a horizontal plane.
17. The shoe sole (28) of any one of claims 1-16, wherein:
the upper surface of a side portion of the bottom sole (128) is substantially flat,
as viewed in a frontal plane cross-section when the shoe sole (28) is in an upright,
unloaded condition.
18. The shoe sole (28) of any one of claims 1-17, including a combined midsole and lift
(127), and wherein the thickness of the midsole and lift (127) of a portion of the
shoe sole (28) having a concavely rounded outer surface (31), as measured in a first
frontal plane cross-section when the shoe sole (28) is in an upright, unloaded condition,
is greater than the thickness of the midsole and lift (127) of a different sole portion
which does not have a concavely rounded outer surface, as measured in a second frontal
plane cross-section, when the shoe sole (28) is in an upright, unloaded condition.
19. The shoe sole (28) as claimed in claim 18, wherein the thickness of the midsole and
lift (127) is defined as the distance between any point on a top surface of the combined
midsole and lift (127) and the closest point on a bottom surface of the combined midsole
and lift (127), as viewed in a frontal plane cross-section when the shoe sole (28)
is in an upright, unloaded condition.
20. The shoe sole (28) of any one of claims 18-19, wherein the lift is a heel lift.
21. The shoe sole (28) of any one of claims 1-20, wherein the at least one concavely rounded
portion of the outer surface (31) is also concavely rounded relative to an inner section
of the shoe sole (28) located directly adjacent to the concavely rounded portion of
the outer surface (31), as viewed in a horizontal plane when the shoe sole (28) is
in an upright, unloaded condition.
22. The shoe sole (28) of any one of claims 1-21, wherein the portion of the shoe sole
(28) with a concavely rounded outer surface (31) has a thickness which decreases gradually
through successive, adjacent frontal plane cross-sections to thereby increase the
torsional flexibility of the shoe sole (28), when the shoe sole (28) is in an upright,
unloaded condition.
23. The shoe sole (28) of any one of claims 1-22, wherein the uppermost portion (53a')
of the at least one concavely rounded portion of the outer surface (31) forms an arc
of more than 90°, as viewed in a frontal plane cross-section when the shoe sole (28)
is in an upright, unloaded condition.
24. The shoe sole (28) of any one of claims 1-23, wherein the portion of the shoe sole
(28) which has a concavely rounded outer surface (31) further includes an area of
increased material density to form a structural support or propulsion element for
the foot (27) of an intended wearer.
25. The shoe sole (28) of any one of claims 1-24, wherein the midsole part of the concavely
rounded portion of the outer surface (31) includes an upper part (53a') of the outer
surface (31), as viewed in a frontal plane cross-section when the shoe sole (28) is
in an upright, unloaded condition.
26. The shoe sole (28) of any one of claims 1-25, wherein the concavely rounded portion
of the outer surface (31) is located only on a side portion of the shoe sole (28),
as viewed in a frontal plane cross-section when the shoe sole (28) is in an upright,
unloaded condition.
27. A shoe sole (28) as claimed in any one of claims 1-26, wherein at least part of the
concavely rounded portion of the outer surface (31) of the shoe sole (28) is formed
by a plurality of substantially straight line segments which, taken together, approximate
a concavely rounded surface portion, as viewed in a frontal plane cross-section when
the shoe sole (28) is in an upright, unloaded condition.
28. A shoe sole (28) as claimed in any one of claims 1-27, wherein a heel area of the
shoe sole (28) has a thickness that is greater than the thickness of the shoe sole
(28) in a forefoot area.
29. A shoe sole (28) as claimed in any one of claims 1-28, including a tread pattern (60,
62) on at least part of the outer surface (31) of the shoe sole (28).
1. Schuhsohle (28) für einen Schuh mit:
einer Laufsohle (128);
einer Zwischensohle (127), die weicher ist als die Laufsohle (128);
einer Fersenerhöhung (127);
einer Innenfläche (30) mit mindestens einem Abschnitt, der relativ zu einem Teil der
Schuhsohle (28) konvex gerundet ist, der direkt angrenzend an den konvex gerundeten
Abschnitt der Innenfläche (30) angeordnet ist, in einem Vorderebenen-Querschnitt betrachtet,
wenn sich die Schuhsohle (28) in einem aufrechten, unbelasteten Zustand befindet;
einer Außenfläche (31) mit einem obersten Abschnitt (53a'), der sich mindestens bis
zur Höhe des untersten Punkts (30') der Innenfläche (30) erstreckt, in einem Vorderebenen-Querschnitt
betrachtet, wenn sich die Schuhsohle (28) in einem aufrechten, unbelasteten Zustand
befindet; dadurch gekennzeichnet, daß:
die Außenfläche (31) mindestens einen konkav gerundeten Abschnitt aufweist, der sich
mindestens entlang einer Seite der Schuhsohle (28) nach unten mindestens annähernd
bis zu einem untersten Punkt (28') der Schuhsohlenseite erstreckt, wobei die Konkavität
des konkav gerundeten Abschnitts der Außenfläche (31) relativ zu einem Innenteil der
Schuhsohle (28) bestimmt ist, der direkt angrenzend an den konkav gerundeten Abschnitt
der Außenfläche (31) angeordnet ist, in einem Vorderebenen-Querschnitt betrachtet,
wenn sich die Schuhsohle (28) in einem aufrechten, unbelasteten Zustand befindet;
und
wobei der konkav gerundete Abschnitt der Außenfläche (31) der Seite der Schuhsohle
(28) einen durch die Zwischensohle (127) gebildeten Teil aufweist und der Zwischensohlenteil
des konkav gerundeten Abschnitts der Außenfläche (31) sich unter eine am weitesten
seitlich gelegene Ausdehnung (28a') der Schuhsohlenseite erstreckt, so daß der gerundete
Abschnitt der Schuhsohlenseite sich verformt, um unter der Körpergewichtslast eines
Trägers während einer seitlichen Bewegung der Schuhsohle (28) einfach flach zu werden,
so daß eine verbesserte Seitenstabilität geboten wird.
2. Schuhsohle (28) nach Anspruch 1, wobei der mindestens eine konkav gerundete Abschnitt
der Außenfläche (31) an einer oder mehreren Stellen auf der Schuhsohle (28) angeordnet
ist, die den Stellen eines oder mehrerer der folgenden Teile des Fußes eines vorgesehenen
Trägers am nächsten sind, wenn er sich im Schuh befindet: die Basis des Calcaneus
(95), der laterale Tuberositas des Calcaneus (95), die Basis des fünften Metatarsalknochens
(97), der Kopf des fünften Metatarsalknochens (96), der Kopf des ersten Metatarsalknochens
(96) und der Kopf der ersten distalen Phalanx (98).
3. Schuhsohle (28) nach einem der Ansprüche 1 bis 2, wobei:
der konkav gerundete Abschnitt der Außenfläche (31) sich mindestens entlang einer
Schuhsohlenseite nach oben bis zu einer Stelle auf der Schuhsohlenseite erstreckt,
die einer am weitesten seitlich gelegenen Ausdehnung (28a') der Schuhsohlenseite am
nächsten ist, in einem Vorderebenen-Querschnitt betrachtet, wenn sich die Schuhsohle
(28) in einem aufrechten, unbelasteten Zustand befindet.
4. Schuhsohle (28) nach einem der Ansprüche 1 bis 2, wobei:
der konkav gerundete Abschnitt der Außenfläche (31) sich mindestens entlang einer
Schuhsohlenseite nach oben durch eine am weitesten seitlich gelegene Ausdehnung (28a')
der Schuhsohlenseite erstreckt, in einem Vorderebenen-Querschnitt betrachtet, wenn
sich die Schuhsohle (28) in einem aufrechten, unbelasteten Zustand befindet.
5. Schuhsohle (28) nach einem der Ansprüche 1 bis 4, wobei:
mindestens ein unterster Teil des konkav gerundeten Abschnitts der Außenfläche
(31) von der Laufsohle (128) gebildet wird.
6. Schuhsohle (28) nach einem der Ansprüche 1 bis 5, wobei:
mindestens ein Teil einer unteren Fläche der Zwischensohle (127) und mindestens
ein Teil einer oberen Fläche der Laufsohle (128) im wesentlichen flach sind, in einem
Vorderebenen-Querschnitt betrachtet, wenn sich die Schuhsohle (28) in einem aufrechten,
unbelasteten Zustand befindet.
7. Schuhsohle (28) nach einem der Ansprüche 1 bis 6, wobei:
der konkav gerundete Zwischensohlenteil der Außenfläche (31) mindestens an einer
Stelle auf der Schuhsohle (28) angeordnet ist, die der Stelle der Basis des Calcaneus
(95) des Fußes eines vorgesehenen Trägers, wenn er sich im Schuh befindet, am nächsten
ist.
8. Schuhsohle (28) nach einem der Ansprüche 1 bis 7, wobei:
der konkav gerundete Zwischensohlenteil der Außenfläche (31) mindestens an einer
Stelle auf der Schuhsohle (28) angeordnet ist, die der Stelle des lateralen Tuberositas
des Calcaneus (95) des Fußes eines vorgesehenen Trägers, wenn er sich im Schuh befindet,
am nächsten ist.
9. Schuhsohle (28) nach einem der Ansprüche 1 bis 8, wobei:
der konkav gerundete Zwischensohlenteil der Außenfläche (31) mindestens an einer
Stelle auf der Schuhsohle (28) angeordnet ist, die der Stelle der Basis des fünften
Metatarsalknochens (97) des Fußes eines vorgesehenen Trägers, wenn er sich im Schuh
befindet, am nächsten ist.
10. Schuhsohle (28) nach einem der Ansprüche 1 bis 9, wobei:
der konkav gerundete Zwischensohlenteil der Außenfläche (31) mindestens an einer
Stelle auf der Schuhsohle (28) angeordnet ist, die der Stelle des Kopfes des fünften
Metatarsalknochens (96) des Fußes eines vorgesehenen Trägers, wenn er sich im Schuh
befindet, am nächsten ist.
11. Schuhsohle (28) nach einem der Ansprüche 1 bis 10, wobei:
der konkav gerundete Zwischensohlenteil der Außenfläche (31) mindestens an einer
Stelle der Schuhsohle (28) angeordnet ist, die der Stelle des Kopfes des ersten Metatarsalknochens
(96) des Fußes eines vorgesehenen Trägers, wenn er sich im Schuh befindet, am nächsten
ist.
12. Schuhsohle (28) nach einem der Ansprüche 1 bis 11, wobei:
der konkav gerundete Zwischensohlenteil der Außenfläche (31) mindestens an einer
Stelle auf der Schuhsohle (28) angeordnet ist, die der Stelle des Kopfes der ersten
distalen Phalanx (98) des Fußes eines vorgesehenen Trägers, wenn er sich im Schuh
befindet, am nächsten ist.
13. Schuhsohle (28) nach einem der Ansprüche 1 bis 12, wobei die Schuhsohle (28) mindestens
zwei konkav gerundete Abschnitte der Außenfläche (31) aufweist, die jeweils eine Zwischensohle
(127) aufweisen und auf gegenüberliegenden Seiten der Schuhsohle (28) angeordnet sind,
in einem Vorderebenen-Querschnitt betrachtet, wenn sich die Schuhsohle (28) in einem
aufrechten, unbelasteten Zustand befindet.
14. Schuhsohle (28) nach einem der Ansprüche 1 bis 6 und Anspruch 13, wenn dieser von
einem der Ansprüche 1 bis 6 abhängig ist, wobei der Vorderebenen-Querschnitt im Fersenbereich
angeordnet ist.
15. Schuhsohle (28) nach einem der Ansprüche 1 bis 14, wobei die Dicke der Schuhsohle
(28) von einer Sohlendicke mindestens an einem der konkav gerundeten Abschnitte der
Außenfläche (31) der Schuhsohle (28) bis zu einer kleineren Sohlendicke auf der Seite
des konkav gerundeten Abschnitts der Außenfläche (31) allmählich abnimmt, in einer
Horizontalebene betrachtet, um dadurch Torsionsflexibilität und Einsparungen am Gewicht
der Schuhsohle (28) zu ermöglichen.
16. Schuhsohle (28) nach Anspruch 15, wobei die Dicke der Schuhsohle (28) auf beiden Seiten
des konkav gerundeten Abschnitts der Außenfläche (31) allmählich abnimmt, in einer
Horizontalebene betrachtet.
17. Schuhsohle (28) nach einem der Ansprüche 1 bis 16, wobei:
die obere Fläche eines Seitenabschnitts der Laufsohle (128) im wesentlichen flach
ist, in einem Vorderebenen-Querschnitt betrachtet, wenn die sich Schuhsohle (28) in
einem aufrechten, unbelasteten Zustand befindet.
18. Schuhsohle (28) nach einem der Ansprüche 1 bis 17, mit einer kombinierten Zwischensohle/Erhöhung
(127) und wobei die Dicke der Zwischensohle/Erhöhung (127) eines Abschnitts der Schuhsohle
(28) mit einer konkav gerundeten Außenfläche (31), in einem ersten Vorderebenen-Querschnitt
gemessen, wenn sich die Schuhsohle (28) in einem aufrechten, unbelasteten Zustand
befindet, größer ist als die Dicke der Zwischensohle/Erhöhung (127) eines anderen
Sohlenabschnitts, der keine konkav gerundete Außenfläche hat, in einem zweiten Vorderebenen-Querschnitt
gemessen, wenn sich die Schuhsohle (28) in einem aufrechten, unbelasteten Zustand
befindet.
19. Schuhsohle (28) nach Anspruch 18, wobei die Dicke der Zwischensohle/Erhöhung (127)
als der Abstand zwischen irgendeinem Punkt auf einer oberen Fläche der kombinierten
Zwischensohle/Erhöhung (127) und dem dichtesten Punkt auf einer unteren Fläche der
kombinierten Zwischensohle/Erhöhung (127) definiert ist, in einem Vorderebenen-Querschnitt
betrachtet, wenn sich die Schuhsohle (28) in einem aufrechten, unbelasteten Zustand
befindet.
20. Schuhsohle (28) nach einem der Ansprüche 18 bis 19, wobei die Erhöhung eine Fersenerhöhung
ist.
21. Schuhsohle (28) nach einem der Ansprüche 1 bis 20, wobei der mindestens eine konkav
gerundete Abschnitt der Außenfläche (31) relativ zu einem Innenteil der Schuhsohle
(28) auch konkav gerundet ist, der direkt angrenzend an den konkav gerundeten Abschnitt
der Außenfläche (31) angeordnet ist, in einer Horizontalebene betrachtet, wenn sich
die Schuhsohle (28) in einem aufrechten, unbelasteten Zustand befindet.
22. Schuhsohle (28) nach einem der Ansprüche 1 bis 21, wobei der Abschnitt der Schuhsohle
(28) mit einer konkav gerundeten Außenfläche (31) eine Dicke hat, die durch aufeinanderfolgende,
angrenzende Vorderebenen-Querschnitte allmählich abnimmt, um dadurch die Torsionsflexibilität
der Schuhsohle (28) zu erhöhen, wenn sich die Schuhsohle (28) in einem aufrechten,
unbelasteten Zustand befindet.
23. Schuhsohle (28) nach einem der Ansprüche 1 bis 22, wobei der oberste Abschnitt (53a')
des mindestens einen konkav gerundeten Abschnitts der Außenfläche (31) einen Bogen
von mehr als 90° bildet, in einem Vorderebenen-Querschnitt betrachtet, wenn sich die
Schuhsohle (28) in einem aufrechten, unbelasteten Zustand befindet.
24. Schuhsohle (28) nach einem der Ansprüche 1 bis 23, wobei der Abschnitt der Schuhsohle
(28), der eine konkav gerundete Außenfläche (31) hat, ferner einen Bereich erhöhter
Materialdichte aufweist, um ein Strukturstütz- oder Fortbewegungselement für den Fuß
(17) eines vorgesehenen Trägers zu bilden.
25. Schuhsohle (28) nach einem der Ansprüche 1 bis 24, wobei der Zwischensohlenteil des
konkav gerundeten Abschnitts der Außenfläche (31) einen oberen Teil (53a') der Außenfläche
(31) aufweist, in einem Vorderebenen-Querschnitt betrachtet, wenn sich die Schuhsohle
(28) in einem aufrechten, unbelasteten Zustand befindet.
26. Schuhsohle (28) nach einem der Ansprüche 1 bis 25, wobei der konkav gerundete Abschnitt
der Außenfläche (31) nur auf einem Seitenabschnitt der Schuhsohle (28) angeordnet
ist, in einem Vorderebenen-Querschnitt betrachtet, wenn sich die Schuhsohle (28) in
einem aufrechten, unbelasteten Zustand befindet.
27. Schuhsohle (28) nach einem der Ansprüche 1 bis 26, wobei mindestens ein Teil des konkav
gerundeten Abschnitts der Außenfläche (31) der Schuhsohle (28) durch mehrere im wesentlichen
gerade Liniensegmente gebildet wird, die sich zusammengenommen einem konkav gerundeten
Oberflächenabschnitt nähern, in einem Vorderebenen-Querschnitt betrachtet, wenn sich
die Schuhsohle (28) in einem aufrechten, unbelasteten Zustand befindet.
28. Schuhsohle (28) nach einem der Ansprüche 1 bis 27, wobei ein Fersenbereich der Schuhsohle
(28) eine Dicke hat, die größer ist als die Dicke der Schuhsohle (28) in einem Vorderfußbereich.
29. Schuhsohle (28) nach einem der Ansprüche 1 bis 28 mit einem Laufflächenmuster (60,
62) auf mindestens einem Teil der Außenfläche (31) der Schuhsohle (28).
1. Semelle de chaussure (28) pour une chaussure, comprenant,:
une semelle inférieure (128);
une semelle intermédiaire (127) plus molle que la semelle inférieure (128);
un sous-bout (127) de talon (127);
une surface intérieure (30) comprenant au moins une partie arrondie de manière convexe
par rapport à une portion de la semelle (28) de la chaussure, qui est située directement
au voisinage de la partie arrondie de manière convexe de la surface intérieure (30),
lorsque la semelle (28) de la chaussure, considérée en coupe transversale dans un
plan frontal, est dans un état droit et non sollicité;
une surface extérieure (31) comportant une partie extrême supérieure (53a') qui s'étend
au moins jusqu'à la hauteur du point le plus bas (30') de la surface intérieure (30),
lorsque la semelle (28) de la chaussure, considérée en coupe transversale dans un
plan frontal, est dans un état droit et non sollicité; caractérisée en ce que :
la surface extérieure (31) comprend au moins une partie arrondie de manière concave
qui s'étend vers le bas le long d'un côté au moins de la semelle (28) de la chaussure,
au moins jusqu'à proximité du point le plus bas (28') du côté de la semelle de la
chaussure, la concavité de la partie arrondie de manière concave de la surface extérieure
(31) étant déterminée par rapport à une partie intérieure de la semelle (28) de la
chaussure, située directement au voisinage de la partie arrondie de manière concave
de la surface extérieure (31), lorsque la semelle (28) de la chaussure, considérée
en coupe transversale dans un plan frontal, est dans un état droit et non sollicité;
et
en ce que la partie arrondie de manière concave de la surface extérieure (31) du côté de la
semelle (28) de la chaussure comprend une portion formée par la semelle intermédiaire
(127), la portion de semelle intermédiaire de la partie arrondie de manière concave
de la surface extérieure (31) s'étendant au-dessous d'une zone de côté extrême (28a')
du côté de la semelle de la chaussure afin que la partie arrondie de celui-ci se déforme
pour s'aplatir facilement sous la charge du poids du corps d'un utilisateur au cours
d'un mouvement de côté de la semelle (28) de la chaussure, pour ainsi assurer une
meilleure stabilité latérale.
2. Semelle de chaussure (28) telle que définie dans la revendication 1, dans laquelle
chaque partie arrondie de manière concave de la surface extérieure (31) est située
au niveau d'un ou de plusieurs emplacements de la semelle (28) de la chaussure proches
des emplacements d'une ou de plusieurs des parties suivantes du pied d'un utilisateur
potentiel, lorsqu'il est placé à l'intérieur de la chaussure : la base du calcanéum
(95), la tubérosité latérale du calcanéum (95), la base du cinquième métatarsien (97),
la tête du cinquième métatarsien (96), la tête du premier métatarsien (96), et la
tête de la première phalange distale (98).
3. Semelle de chaussure (28) selon la revendication 1 ou 2, dans laquelle :
la partie arrondie de manière concave de la surface extérieure (31) s'étend vers
le haut le long d'un côté au moins de la semelle de la chaussure jusqu'à un emplacement
du côté de la semelle de la chaussure, proche d'une zone de côté extrême (28a') de
celui-ci, lorsque la semelle (28) de la chaussure, considérée en coupe transversale
dans un plan frontal, est dans un état droit et non sollicité.
4. Semelle de chaussure (28) selon la revendication 1 ou 2, dans laquelle :
la partie arrondie de manière concave de la surface extérieure (31) s'étend vers
le haut le long d'un côté au moins de la semelle de la chaussure jusqu'au bout d'une
zone de côté extrême (28a') du côté de la semelle de la chaussure, lorsque la semelle
(28) de la chaussure, considérée en coupe transversale dans un plan frontal, est dans
un état droit et non sollicité.
5. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 4, dans laquelle
:
au moins une portion extrême inférieure de la partie arrondie de manière concave
de la surface extérieure (31) est formés par la semelle inférieure (128).
6. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 5, dans laquelle
:
au moins une portion d'une surface inférieure de la semelle intermédiaire (127)
et au moins une portion d'une surface supérieure de la semelle inférieure (128) sont
sensiblement planes, lorsque la semelle (28) de la chaussure, considérée en coupe
transversale dans le plan frontal, est dans un état droit et non sollicité.
7. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 6, dans laquelle
:
la portion de semelle intermédiaire arrondie de manière concave de la surface extérieure
(31) est située au moins au niveau d'un emplacement de la semelle (28) de la chaussure,
proche de l'emplacement de la base du calcanéum (95) du pied d'un utilisateur potentiel,
lorsqu'il est placé à l'intérieur de la chaussure.
8. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 7, dans laquelle
:
la portion de semelle intermédiaire arrondie de manière concave de la surface extérieure
(31) est située au moins au niveau d'un emplacement de la semelle (28) de la chaussure,
proche de l'emplacement de la tubérosité latérale du calcanéum (95) du pied d'un utilisateur
potentiel, lorsqu'il est placé à l'intérieur de la chaussure.
9. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 8, dans laquelle
:
la portion de semelle intermédiaire arrondie de manière concave de la surface extérieure
(31) est située au moins au niveau d'un emplacement de la semelle (28) de la chaussure,
proche de l'emplacement de la base du cinquième métatarsien (97) du pied d'un utilisateur
potentiel, lorsqu'il est placé à l'intérieur de la chaussure.
10. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 9, dans laquelle
:
la portion de semelle intermédiaire arrondie de manière concave de la surface extérieure
(31) est située au moins au niveau d'un emplacement de la semelle (28) de la chaussure,
proche de l'emplacement de la tête du cinquième métatarsien (96) du pied d'un utilisateur
potentiel, lorsqu'il est placé à l'intérieur de la chaussure.
11. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 10, dans laquelle
:
la portion de semelle intermédiaire arrondie de manière concave de la surface extérieure
(31) est située au moins au niveau d'un emplacement de la semelle (28) de la chaussure,
proche de l'emplacement de la tête du premier métatarsien (96) du pied d'un utilisateur
potentiel, lorsqu'il est placé à l'intérieur de la chaussure.
12. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 11, dans laquelle
:
la portion de semelle intermédiaire arrondie de manière concave de la surface extérieure
(31) est située au moins au niveau d'un emplacement de la semelle (28) de la chaussure,
proche de l'emplacement de la tête de la première phalange distale (98) du pied d'un
utilisateur potentiel, lorsqu'il est placé à l'intérieur de la chaussure.
13. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 12, dans laquelle
la semelle (28) de la chaussure comprend au moins deux parties arrondies de manière
concave de la surface extérieure (31) comprenant chacune la semelle intermédiaire
(127) et situées sur des côtés opposés de la semelle (28) de la chaussure, lorsque
la semelle (28) de la chaussure, considérée en coupe transversale dans un plan frontal,
est dans un état droit et non sollicité.
14. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 6 et la revendication
13, lorsqu'elle est dépendante de l'une quelconque des revendications 1 à 6, dans
laquelle la coupe transversale en plan frontal est située dans la zone du talon.
15. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 14, dans laquelle
l'épaisseur de la semelle (28) de la chaussure diminue progressivement d'une épaisseur
de semelle au niveau de l'une au moins des parties arrondies de manière concave de
la surface extérieure (31) de la semelle (28) de la chaussure à une épaisseur de semelle
inférieure du côté de la partie arrondie de manière concave de la surface extérieure
(31), lorsqu'on la considère dans un plan horizontal, pour ainsi assurer une souplesse
en torsion et un allégement de la semelle (28) de la chaussure.
16. Semelle de chaussure (28) telle que définie dans la revendication 15, dans laquelle
l'épaisseur de la semelle (28) de la chaussure diminue progressivement des deux côtés
de la partie arrondie de manière concave de la surface extérieure (31), lorsqu'on
la considère dans un plan horizontal.
17. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 16, dans laquelle
:
la surface supérieure d'une partie de côté de la semelle inférieure (128) est sensiblement
plane, lorsque la semelle (28) de la chaussure, considérée en coupe transversale dans
un plan frontal, est dans un état droit et non sollicité.
18. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 17, comprenant
une semelle intermédiaire et un sous-bout combinés (127), et dans laquelle l'épaisseur
de la semelle intermédiaire et du sous-bout combinés (127) d'une partie de la semelle
(28) de la chaussure présentant une surface extérieure (31) arrondie de manière concave,
mesurée dans une première coupe transversale en plan frontal, lorsque la semelle (28)
de la chaussure est dans un état droit et non sollicité, est supérieure à l'épaisseur
de la semelle intermédiaire et du sous-bout combinés (127) d'une partie différente
de la semelle ne présentant pas une surface extérieure arrondie de manière concave,
mesurée dans une seconde coupe transversale en plan frontal, lorsque la semelle (28)
de la chaussure est dans un état droit et non sollicité.
19. Semelle de chaussure (28) telle que définie dans la revendication 18, dans laquelle
l'épaisseur de la semelle intermédiaire et du sous-bout combinés (127) est définie
comme la distance entre un point quelconque d'une surface supérieure de la semelle
intermédiaire et du sous-bout combinés (127) et le point le plus proche d'une surface
inférieure de la semelle intermédiaire et du sous-bout combinés (127), lorsque la
semelle (28) de la chaussure, considérée en coupe transversale dans un plan frontal,
est dans un état droit et non sollicité.
20. Semelle de chaussure (28) selon la revendication 18 ou 19, dans laquelle le sous-bout
est un sous-bout de talon.
21. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 20, dans laquelle
chaque partie arrondie de manière concave de la surface extérieure (31) est également
arrondie de manière concave par rapport à une portion intérieure de la semelle (28)
de la chaussure, située directement au voisinage de la partie arrondie de manière
concave de la surface extérieure (31), lorsque la semelle (28) de la chaussure, considérée
dans un plan horizontal, est dans un état droit et non sollicité.
22. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 21, dans laquelle
la partie de la semelle (28) de la chaussure pourvue d'une surface extérieure arrondie
de manière concave (31) a une épaisseur qui diminue progressivement d'un bout à l'autre
de coupes transversales en plan frontal adjacentes successives pour ainsi augmenter
la souplesse en torsion de la semelle (28) de la chaussure, lorsque la semelle (28)
de la chaussure est dans un état droit et non sollicité.
23. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 22, dans laquelle
la portion extrême supérieure (53a') de chaque partie arrondie de manière concave
de la surface extérieure (31) forme un arc de plus de 90° degrés, lorsque la semelle
(28) de la chaussure, considérée en coupe transversale dans un plan frontal, est dans
un état droit et non sollicité.
24. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 23, dans laquelle
la partie de la semelle (28) de la chaussure qui présente une surface extérieure (31)
arrondie de manière concave comprend également une zone de densité de matière accrue
pour former un élément de support structural ou de propulsion pour le pied (27) d'un
utilisateur potentiel.
25. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 24, dans laquelle
la portion de semelle intermédiaire de la partie arrondie de manière concave de la
surface extérieure (31) comprend une portion supérieure (53a') de la surface extérieure
(31), lorsque la semelle (28) de la chaussure, considérée en coupe transversale dans
un plan frontal, est dans un état droit et non sollicité.
26. Semelle de chaussure (28) selon l'une quelconque des revendications 1 à 25, dans laquelle
la partie arrondie de manière concave de la surface extérieure (31) est située uniquement
sur une portion de côté de la semelle (28) de la chaussure, lorsque la semelle (28)
de la chaussure, considérée en coupe transversale dans un plan frontal, est dans un
état droit et non sollicité.
27. Semelle de chaussure (28) telle que définie dans l'une quelconque des revendications
1 à 26, dans laquelle une portion au moins de la partie arrondie de manière concave
de la surface extérieure (31) de la semelle (28) de la chaussure est formée par plusieurs
segments de ligne sensiblement droits qui, pris collectivement, se rapprochent d'une
partie de surface arrondie de manière concave, lorsque la semelle (28) de la chaussure,
considérée en coupe transversale dans un plan frontal, est dans un état droit et non
sollicité.
28. Semelle de chaussure (28) telle que définie dans l'une quelconque des revendications
1 à 27, dans laquelle une zone de talon de la semelle (28) de la chaussure a une épaisseur
supérieure à l'épaisseur de la semelle (28) de la chaussure dans une zone d'avant-pied.
29. Semelle de chaussure (28) telle que définie dans l'une quelconque des revendications
1 à 28, comprenant une configuration en relief (60, 62) sur une portion au moins de
la surface extérieure (31) de la semelle (28) de la chaussure.