U.S. patent application number 12/776253 was filed with the patent office on 2010-12-09 for shoe.
This patent application is currently assigned to Skechers U.S.A. Inc. II. Invention is credited to Eckhard Knoepke, David Raysse, Savva Teteriatnikov, Julie Zhu.
Application Number | 20100307028 12/776253 |
Document ID | / |
Family ID | 43732741 |
Filed Date | 2010-12-09 |
United States Patent
Application |
20100307028 |
Kind Code |
A1 |
Teteriatnikov; Savva ; et
al. |
December 9, 2010 |
SHOE
Abstract
A shoe having a toe region, a middle region, a heel region, and
a multi-layer, multi-density midsole; the midsole being comprised
of at least a shank and a lower layer; the bottom surface of the
shank having at least one longitudinal concavity and at least one
longitudinal convexity, the longitudinal concavity typically
occupying a substantial portion of the heel region and the
longitudinal convexity typically occupying a portion of the middle
region. Collectively, these elements contribute to making the shoe
appropriate for both walking and higher impact activities such as
running, and simulating the effect, and imparting the fitness
benefits, of use on a sandy beach or on a giving or uneven surface
regardless of the actual hardness of the surface.
Inventors: |
Teteriatnikov; Savva;
(Venice, CA) ; Raysse; David; (Los Angeles,
CA) ; Knoepke; Eckhard; (Redondo Beach, CA) ;
Zhu; Julie; (Redondo Beach, CA) |
Correspondence
Address: |
KLEINBERG & LERNER, LLP
1875 CENTURY PARK EAST, SUITE 1150
LOS ANGELES
CA
90067
US
|
Assignee: |
Skechers U.S.A. Inc. II
Manhattan Beach
CA
|
Family ID: |
43732741 |
Appl. No.: |
12/776253 |
Filed: |
May 7, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12557276 |
Sep 10, 2009 |
7779557 |
|
|
12776253 |
|
|
|
|
61122911 |
Dec 16, 2008 |
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Current U.S.
Class: |
36/108 ; 36/30R;
36/45 |
Current CPC
Class: |
A43B 13/145 20130101;
A43B 13/127 20130101 |
Class at
Publication: |
36/108 ; 36/30.R;
36/45 |
International
Class: |
A43B 23/00 20060101
A43B023/00; A43B 13/12 20060101 A43B013/12 |
Claims
1. A shoe having an upper, a midsole, and an outsole, wherein said
midsole comprises: a toe region, a middle region, a heel region, an
upper layer, a shank and a lower layer, wherein said shank has a
bottom surface, said lower layer has a top surface, said lower
layer being located substantially between the outsole and the
shank, said shank being located substantially between the lower
layer and the upper layer, the bottom surface of said shank
substantially facing the top surface of said lower layer, and said
upper layer and said lower layer each having a density wherein the
density of the upper layer is denser than the density of the lower
layer.
2. The shoe of claim 1 wherein said bottom surface of said shank
has a longitudinal concavity and a longitudinal convexity, wherein
said longitudinal concavity occupies a substantial portion of the
heel region, and said longitudinal convexity occupies a portion of
the middle region.
3. The shoe of claim 1 wherein said bottom surface of said shank
has a plurality of longitudinal concavities and at least one
longitudinal convexity, said plurality of longitudinal concavities
comprising at least a first longitudinal concavity and a second
longitudinal concavity, wherein said first longitudinal concavity
occupies a substantial portion of the heel region and said second
longitudinal concavity occupies a portion of the toe region, and
said longitudinal convexity occupies a portion of the middle
region.
4. The shoe of claim 2 wherein said shank has a density greater
than said density of the upper layer.
5. The shoe of claim 3 wherein said shank has a density greater
than said density of the upper layer.
6. The shoe of claim 4 wherein said shank contains a cavity in a
portion of said middle region.
7. The shoe of claim 5 wherein said shank contains a cavity in a
portion of said middle region.
8. The shoe of claim 4 wherein said shank occupies a substantial
portion of the entire length of the midsole.
9. The shoe of claim 5 wherein said shank occupies a substantial
portion of the entire length of the midsole.
10. The shoe of claim 6 wherein said shank occupies a substantial
portion of said heel region and a substantial portion of said
middle region.
11. The shoe of claim 7 wherein said shank occupies a substantial
portion of said heel region and a substantial portion of said
middle region.
12. The shoe of claim 4 wherein said bottom surface of said shank
contains a transverse concavity or a transverse convexity.
13. The shoe of claim 5 wherein said bottom surface of said shank
contains a transverse concavity or a transverse convexity.
14. A shoe having an upper, a midsole, and an outsole, wherein said
midsole comprises: a toe region, a middle region, a heel region, a
shank and a lower layer, wherein said shank has a bottom surface,
said lower layer has a top surface, said lower layer being located
substantially between the outsole and the shank, and the bottom
surface of said shank substantially facing the top surface of said
lower layer.
15. The shoe of claim 14 wherein said bottom surface of said shank
has a longitudinal concavity and a longitudinal convexity, wherein
said longitudinal concavity occupies a substantial portion of the
heel region, and said longitudinal convexity occupies a portion of
the middle region.
16. The shoe of claim 14 wherein said bottom surface of said shank
has a plurality of longitudinal concavities and at least one
longitudinal convexity, said plurality of longitudinal concavities
comprising at least a first longitudinal concavity and a second
longitudinal concavity, wherein said first longitudinal concavity
occupies a substantial portion of the heel region and said second
longitudinal concavity occupies a portion of the toe region, and
said longitudinal convexity occupies a portion of the middle
region.
17. The shoe of claim 15 wherein said shank has a density greater
than said density of the lower layer.
18. The shoe of claim 16 wherein said shank has a density greater
than said density of the lower layer.
19. The shoe of claim 17 wherein said shank contains a cavity in a
portion of said middle region.
20. The shoe of claim 18 wherein said shank contains a cavity in a
portion of said middle region.
21. The shoe of claim 17 wherein said shank occupies a substantial
portion of the entire length of the midsole.
22. The shoe of claim 18 wherein said shank occupies a substantial
portion of the entire length of the midsole.
23. The shoe of claim 19 wherein said shank occupies a substantial
portion of said heel region and a substantial portion of said
middle region.
24. The shoe of claim 20 wherein said shank occupies a substantial
portion of said heel region and a substantial portion of said
middle region.
25. The shoe of claim 17 wherein said bottom surface of said shank
contains a transverse concavity or a transverse convexity.
26. The shoe of claim 18 wherein said bottom surface of said shank
contains a transverse concavity or a transverse convexity.
Description
[0001] This application is a continuation in part of patent
application Ser. No. 12/557,276 filed on Sep. 10, 2009.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to footwear and, in
particular, to a shoe with fitness benefits which can be used
during high impact activities such as running. The fitness benefits
are imparted by a unique running or walking motion which is induced
primarily by the shoe's midsole. The midsole has multiple layers
and multiple densities. One of the layers of the midsole is a shank
that allows the shoe to be lighter and to have a lower-profile
which results in the user's foot being positioned closer to the
ground; the shank also provides increased heel and midfoot support.
As a result of these qualities / characteristics, the shoe can be
worn during high impact activities such as running. The motion
induced by the shoe is mimics the effect of running or walking on a
sandy beach or on a giving or uneven surface.
[0004] 2. Description of the Related Art
[0005] Shoes are designed for many purposes--from protection on the
job, to performance during athletic activity, to everyday use.
Shoes have also been used to promote physical health and activity.
Increasingly, shoes have been designed to increase the fitness
benefits that users get from everyday uses such as walking.
However, there continues to be a need for such shoes that increase
the fitness benefits to users yet are comfortable, easy to use, and
able to be used for high impact activities such as running.
[0006] Walking and running are the easiest and most beneficial
forms of exercise. When done properly and with the appropriate
footwear, they strengthen the heart, improve cardiovascular health,
increase one's stamina and improve posture. Walking and running
also help to strengthen and tone one's muscles and maintain joint
flexibility.
[0007] Prior art shoes have attempted to improve the user's fitness
by mimicking walking barefoot. See, for example, U.S. Pat. No.
6,341,432 to Muller. Such shoes can include an abrupt, discrete
pivot point provided by a hard inclusion. Consequently, in every
step taken during normal walking while wearing such shoes, the user
is forced to overcome this abrupt, discrete pivot point. This can
result in significant pain and discomfort.
[0008] Prior art shoes that have attempted to mimic walking
barefoot have been rather large and clunky. They also have not been
suitable for running or other high impact activities due to their
relatively significant weight, high midsole profile, and low level
of heel and midfoot support . In order for a shoe to be optimum for
running and other high impact activities, it must have a relatively
low profile which allows the foot to be positioned closer to the
ground. In addition, the shoe must be light weight and provide
sufficient support to the user's foot.
[0009] The present invention aims to provide a way of mimicking
running or walking on a sandy beach or on a giving or uneven
surface, while not inducing any pain or discomfort from doing so.
By mimicking running or walking on a sandy beach and/or on an
uneven surface, the present invention aims to significantly
increase the fitness and health benefits of everyday running or
walking by requiring the user to exert additional effort and energy
and to use muscles that the user otherwise would not use if wearing
ordinary footwear, again all without inducing any pain or
discomfort.
SUMMARY OF THE INVENTION
[0010] It is an object of the present invention to provide a shoe
that can be used during high impact activities such as running and
which provides certain fitness benefits not imparted by ordinary
shoes. It does this by mimicking the effects of running or walking
on a sandy beach or on a giving or uneven surface without inducing
any pain or discomfort from doing so.
[0011] The present invention is a shoe comprising an upper, an
outsole, and a midsole, each having a medial side and a lateral
side. In a preferred embodiment, the midsole is affixed to the
upper and the outsole is affixed to the midsole. The upper,
midsole, and outsole each has a frontmost point and a rearmost
point substantially opposite the frontmost point. As the terms
imply, each frontmost point is closer to the user's toes than each
rearmost point while at the same time each rearmost point is closer
to the user's heel than each frontmost point.
[0012] The midsole is unique in that it comprises a plurality of
layers. In a preferred embodiment, the midsole comprises an upper
layer, a shank and a lower layer. In a preferred embodiment, the
upper layer has a first density and the lower layer has a second
density. The second density of the lower layer is less than the
first density of the upper layer.
[0013] Throughout the midsole, the thickness of the upper layer and
lower layer may vary. In some instances, the lower layer is thicker
than the upper layer or vice versa. In the regions in which the
less dense lower layer is thicker, such as the heel, the midsole is
less stable. Therefore, it provides the effect of walking or
running on sand or an uneven surface. However, in regions in which
the less dense lower layer is thicker, the relatively denser upper
layer and shank provide some compensating stability to the user's
foot. The benefits of the different densities and thicknesses will
be further discussed herein below.
[0014] The shank is positioned in between the upper layer and the
lower layer. The addition of the shank provides at least two groups
of benefits. The first group of benefits is that the shank allows
the midsole to be constructed with a relatively thinner upper
layer. Because the midsole is made thinner due to the shank, the
users' foot is placed closer to the ground and therefore provides
better footing for high impact activities such as running.
Furthermore, the thinner upper layer not only is more aesthetically
pleasing, but since there is less material, the midsole is lighter
than a midsole with a relatively thick upper layer, thereby making
the entire shoe lighter. The second group of benefits is that the
shank provides enhanced support to the user's foot and thus allows
the user to engage in faster paced activities such as running. The
shank also disperses the force and pressure from the foot strike
more evenly throughout the shoe.
[0015] The shoe has a front tip that is located at the farthest
forward point of the shoe when moving from the rear portion to the
front portion. The shoe has a rear tip that is located at the
farthest rearward point of the shoe when moving from the front
portion to the rear portion. In a preferred embodiment, the front
tip coincides with the frontmost point of the upper, the frontmost
point of the midsole, or the frontmost point of the outsole while
the rear tip coincides with the rearmost point of the upper, the
rearmost point of the midsole, or the rearmost point of the
outsole. In a preferred embodiment, the frontmost point of the
upper, the frontmost point of the midsole, and the frontmost point
of the outsole are all located relatively close to one another
while the rearmost point of the upper, the rearmost point of the
midsole, and the rearmost point of the outsole are all located
relatively close to one another.
[0016] The upper, midsole, and outsole each has a toe region. The
toe region includes the region that extends substantially from the
medial side to the lateral side at a location that begins in the
vicinity of the front tip of the shoe and extends from there to a
location that is approximately one third of the distance toward the
rear tip of the shoe.
[0017] The upper, midsole, and outsole each has a heel region. The
heel region includes the region that extends substantially from the
medial side to the lateral side at a location that begins in the
vicinity of the rear tip of the shoe and extends from there to a
location that is approximately one third of the distance toward the
front tip of the shoe.
[0018] The upper, midsole, and outsole each has a middle region.
The middle region includes the region that extends substantially
from the medial side to the lateral side at a location that extends
approximately between the toe region and the heel region.
[0019] In a preferred embodiment, the midsole further comprises an
upper layer, shank and a lower layer, the upper layer having a
first density and the lower layer having a second density different
from the first density. In between the upper layer and lower layer,
there is a shank that extends longitudinally from the heel region
to the toe region. The upper layer, the shank and the lower layer
each to has a top surface and a bottom surface.
[0020] In a preferred embodiment, the bottom surface of the upper
layer rests on the top surface of the shank, and the bottom surface
of the shank rests on the top surface of the lower layer.
[0021] In a preferred embodiment, the shank extends from the heel
region to the toe region and extends longitudinally along the
entire midsole. However, without deviating from the scope of the
invention, the shank may extend from the heel region to the middle
region or part of the toe region without extending the entire
length of the shoe.
[0022] In a preferred embodiment, the bottom surface of the upper
layer is in substantially continuous contact with, and
substantially conforms to, the top surface of the shank. Likewise,
the bottom surface of the shank is in substantially continuous
contact with, and substantially conforms to, the top surface of the
lower layer.
[0023] In a preferred embodiment, the shank is comprised of two
portions, a top portion and a bottom portion. The top portion and
the bottom portion of the shank can be separate pieces which are
affixed together or alternatively they can comprise one unitary
structure.
[0024] In a preferred embodiment, as the shank longitudinally
extends along the midsole from the heel region to the toe region,
the bottom surface of the shank forms a single longitudinal
concavity (as defined below) that occupies a substantial portion of
the heel region and terminates at a point in the middle region.
Upon termination of the longitudinal concavity, the bottom surface
of the shank forms a longitudinal convexity (as defined below) that
occupies a portion of the middle region. The longitudinal convexity
then terminates. Upon termination of the longitudinal convexity, a
second longitudinal concavity begins on the bottom surface of the
shank. The second longitudinal concavity on the bottom surface of
the shank occupies a portion of the middle and/or toe regions of
the midsole.
[0025] In a preferred embodiment, due to the shape of the top
portion and bottom portion of the shank, a cavity is formed within
the shank. For reference, the cavity begins at a point
longitudinally closer to the heel region and that point is referred
to as the start of the cavity. The cavity terminates at a point
longitudinally closer to the middle region and that point is
referred to as the end of the cavity. The cavity is completely open
from the lateral to medial side of the shoe. The cavity causes the
shank to provide better support to the heel and midfoot areas of
the foot and disperses the force and pressure of the foot strike
more evenly throughout the shoe.
[0026] In a preferred embodiment, the invention includes an outsole
that, when no load is applied, gently curves continuously upward in
a direction toward the upper beginning at a location near the
middle region of the outsole and ending at a location near the
rearmost point of the upper.
[0027] In this preferred embodiment, the upper layer, shank and the
lower layer of the midsole each extend from at least the vicinity
of the front tip of to the shoe to at least the vicinity of the
rear tip of the shoe.
[0028] In this preferred embodiment, the upper layer is made from a
material having a first density sufficiently dense to provide some
support and stabilization of the user's foot. Typically, in this
preferred embodiment, the upper layer has a durometer hardness
between about 45 and about 65 on the Asker C is scale. The upper
layer typically has a relatively low compressibility so that it
compresses a relatively low, or small, amount under a given
load.
[0029] The lower layer, which may or may not be made of the same
material as the upper layer, has a second density that is different
from the first density and is sufficiently low in density and high
in compressibility so as to allow the lower layer to compress and
deform a higher, or greater, amount under a given weight than the
upper layer would compress and deform under that same weight.
Typically, the lower layer has a durometer hardness between about
20 and about 45 on the Asker C scale. The density of the lower
layer is sufficiently low and the compressibility of the lower
layer is sufficiently high so that under normal running or walking
conditions, the user's foot, first in the heel region, then in the
middle region, and then finally in the toe region, sinks toward the
ground as the lower layer compresses and deforms during use.
[0030] In this preferred embodiment, the shank is made from a
material having a third density sufficiently dense to provide the
primary support and stability to the user's foot. Typically, the
shank has a durometer hardness between about 50 and about 70 on the
Shore D scale. The shank in the area of the heel region and the
middle region is relatively thick and rigid and thereby provides
support and stability to the user's foot in those areas. In
contrast, the shank in the toe area is relatively thin and may even
have a fork-like structure or be completely absent, thus allowing
the toe region to flex during use.
[0031] Due to the hardness and rigidity of the shank, the upper
layer of the midsole may be relatively thin or completely
absent.
[0032] During walking or running while wearing a preferred
embodiment of the instant invention, when the curved heel region of
the outsole strikes the ground, the heel region of the lower layer,
which is less dense and more easily compressed than the upper
layer, deforms to a relatively large degree compared to the upper
layer and the shank. After each such initial heel region contact
with the ground, the user's heel sinks or moves toward the ground
more than it would sink or move in a conventional shoe. This
sinking or downward movement is due primarily to deflection of the
heel region of the outsole and compression of the heel region of
the midsole as they each respond to the increasing weight being
transmitted through the user's heel as the step progresses and the
user's heel continues to bear an increasing amount of the user's
weight until it reaches a maximum. The impact is akin to a heel
striking a sandy beach or a giving or uneven surface. Then, as the
user's weight begins to shift toward the middle region of the shoe,
the shoe rolls forward in a smooth motion, without the user having
to overcome any abrupt or discrete pivot points. Then the lower
layer of the midsole in the middle region and then the toe region
compresses and deforms under the increasing weight of the user's
foot in those regions as the step progresses. This compression and
deformation allows the user's foot to sink further toward the
ground than would be the case with a conventional shoe. The user
then completes the step by pushing off with the forefoot ball area
of the user's foot. This push-off further compresses and deforms
the lower layer in the toe region.
[0033] As used herein, "longitudinal convexities" and "longitudinal
concavities" mean, refer to, and are defined as, respectively,
convexities and concavities that lie only in vertical, longitudinal
planes that extend from any local frontmost point of the shoe to a
corresponding local rearmost point of the shoe when the shoe is in
its normal, upright position. As used herein, "transverse
convexities" and "transverse concavities" mean, refer to, and are
defined as, respectively, convexities and concavities that lie only
in vertical, transverse planes that extend from any local
medialmost point of the shoe to a corresponding local lateralmost
point of the shoe when the shoe is in its normal, upright
position.
[0034] All convexities and concavities in the instant invention,
both longitudinal and transverse, are all identified herein as
being on, and being a part of, the bottom surface of the shank.
Under this convention, each longitudinal convexity and each
transverse convexity identified herein is, to some degree, an
outward bulge of the bottom surface of the shank and each
longitudinal concavity and each transverse concavity identified
herein is, to some degree, an inward depression in the bottom
surface of the shank. The inward depression of each longitudinal
concavity and of each transverse concavity means that the lower
layer is relatively thick wherever the bottom surface of the shank
has a longitudinal or transverse concavity. Similarly, the outward
bulge of each longitudinal convexity and of each transverse
convexity means that the lower layer is relatively thin wherever
the shank has a longitudinal or transverse convexity.
[0035] Each concavity and convexity, as described above, has at
least five primary variables that control the effect of each such
concavity and each such convexity. These primary variables are (1)
the location where each concavity and each convexity is located
from a point where it begins to a point where it ends, (2) the
sharpness or shallowness of each such concavity or convexity, i.e.,
its radius of curvature or radii of curvature, (3) the length or
wavelength of each such concavity or convexity as measured from a
point where it begins to a point where it ends, (4) the amplitude,
i.e., the greatest height of each such concavity or the greatest
depth of each such convexity, and (5) the firmness or
compressibility of the upper layer material with which each such
concavity or convexity is formed. These variables are some of the
primary means by which the effects of the shoe on the user are
controlled. These effects comprise primarily (1) the degree of
softness or hardness felt by the user's foot throughout each step
while wearing the shoe, (2) the amount of energy and effort needed
for the user to complete each step, and (3) the amount of muscle
use, control and coordination necessary for the user to maintain
the user's balance throughout each step.
[0036] The degree of softness or hardness felt by the user's foot
immediately after the heel strike is controlled primarily by a
longitudinal concavity in the bottom surface of the shank located
in the heel region of the lower layer of the midsole. This
longitudinal concavity is typically relatively large, i.e., it
typically has a long length, a large radius of curvature or radii
of curvature, and a large amplitude. This relatively large
longitudinal concavity allows a relatively thick lower layer to be
used in the heel region that can absorb and soften the initial heel
strike of each step. Whereas each longitudinal concavity and each
transverse concavity imparts a relatively soft feel to the user's
foot while walking, each longitudinal convexity and each transverse
convexity imparts a relatively hard feel to the user's foot while
walking. This relative hardness is due to the decreased thickness
of the soft, highly compressible lower layer at each location where
a longitudinal or transverse convexity occurs.
[0037] The shank allows the midsole to be thinner because it
provides a further hardness and rigidity in addition to or in place
of the upper layer. Due to the inclusion of the harder and more
rigid shank, the lower layer can compress and, at the same time,
guide the user's motion without compromising support and stability.
Due to the hardness and rigidity of the shank, as the lower layer
sinks toward the ground due to the compressibility of the lower
layer, the user's foot is still supported and prevented from
excessive lateral movement in the midfoot and heel areas during
use.
[0038] The amount of energy and effort required by the user in each
step is related to the degree of softness or hardness felt by the
user as discussed in the preceding paragraph insofar as each
longitudinal or transverse concavity corresponds to a softer feel
which, in turn, requires more energy and effort to overcome in each
step.
[0039] The amount of muscle use, control and coordination necessary
for the user to maintain the user's balance throughout each step
increases in direct proportion to each one of the following: (1)
increased size, primarily in wavelength and amplitude, of the
longitudinal concavity and/or transverse concavity and (2)
increased compressibility of the lower layer. Increased
longitudinal and/or transverse concavity size in the form of
greater amplitude corresponds to a thicker lower layer. The
compressibility of the lower layer is a physical property inherent
in the material out of which the lower layer is made. It is a
measure of the readiness with which the lower layer compresses
under a given load. A high compressibility means that the lower
layer is highly compressible and can be compressed a high amount
with relative ease. As the compressibility increases, the user must
use more muscle control and coordination to maintain the user's
balance during each step as the weight of the user compresses the
lower layer. This compression is accompanied by a downward movement
of the user's foot as it compresses the lower layer during each
step. This downward compression movement requires balancing by the
user to accommodate inherent instability that accompanies the
compression. This inherent instability is also affected by the
thickness of the lower layer. This thickness, as mentioned above,
increases as longitudinal and/or transverse concavity size of the
bottom surface of the shank increases. As the thickness of the
lower layer increases, the inherent instability increases. Thus,
longitudinal and/or transverse concavities on the bottom surface of
the shank contribute to a less stable walking/running nature of the
shoe. The relative opposite effect is achieved with a longitudinal
and/or transverse convexity on the bottom surface of the shank.
[0040] As mentioned above, the instability results in the user
having to exert more effort and energy while running or walking
than they would if they had been wearing conventional footwear.
This, in turn, imparts various fitness benefits to the user such as
increased muscle toning, better posture and greater burning of
calories.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] By way of example only, selected embodiments and aspects of
the present invention are described below. Each such description
refers to a particular figure ("FIG.") which shows the described
matter. All such figures are shown in drawings that accompany this
specification. Each such figure includes one or more reference
numbers that identify one or more part(s) or element(s) of the
invention.
[0042] FIG. 1 is an exploded perspective view of an embodiment of
the midsole and outsole of the shoe.
[0043] FIG. 2 is a side elevation view of an embodiment of the
midsole and outsole of the shoe.
[0044] FIG. 2A is an exploded side elevation view of an embodiment
of the midsole and outsole of the shoe.
[0045] FIG. 3 is a side elevation view of an embodiment of the
shank.
[0046] FIG. 3A is a front elevation view in cross section of an
embodiment of the shank along line 3A in the direction of the
appended arrows.
[0047] FIG. 3B is a front elevation view in cross section of an
alternative embodiment of the shank along line 3A in the direction
of the appended arrows.
[0048] FIG. 3C is a front elevation view in cross section of
another alternative embodiment of the shank along line 3A in the
direction of the appended arrows.
[0049] FIG. 4 is a perspective view of an embodiment of the
shank.
[0050] FIG. 5A is a side elevation view of a representative shoe
that embodies the instant invention without any load.
[0051] FIG. 5B is a side elevation view of the shoe of FIG. 5A
showing the heel region bearing the load of a user.
[0052] FIG. 5C is a side elevation view of the shoe of FIG. 5A
showing the middle region bearing the load of a user.
[0053] FIG. 5D is a side elevation view of the shoe of FIG. 5A
showing the toe region bearing the load of a user.
[0054] FIG. 6 is an exploded elevation view of FIG. 2 that includes
view plane lines.
[0055] FIG. 6A is a top plan view of the top surface of the upper
layer of the midsole along line 6A-6A in the direction of the
appended arrows.
[0056] FIG. 6B is a bottom plan view of the bottom surface of the
upper layer of the midsole along line 6B-6B in the direction of the
appended arrows.
[0057] FIG. 6C is a top plan view of the top surface of the shank
along line 6C-6C in the direction of the appended arrows.
[0058] FIG. 6D is a bottom plan view of the bottom surface of the
shank along line 6D-6D in the direction of the appended arrows.
[0059] FIG. 6E is a top plan view of the top surface of the lower
layer of the midsole along line 6E-6E in the direction of the
appended arrows.
[0060] FIG. 6F is a bottom plan view of the bottom surface of the
lower layer of the midsole along line 6F-6F in the direction of the
appended arrows.
[0061] FIG. 7 is an exploded perspective view of an alternative
embodiment of the midsole and outsole of the shoe.
[0062] FIG. 8 is a side elevation view of an alternative embodiment
of the midsole and outsole of the shoe.
[0063] FIG. 8A is an exploded side elevation view of an alternative
embodiment of the midsole and outsole of the shoe.
[0064] FIG. 9A is a top plan view of the bottom surface of an
alternative embodiment of the shank along line 6C-6C in the
direction of the appended arrows.
[0065] FIG. 9B is a top plan view of the bottom surface of an
alternative embodiment of the shank along line 6C-6C in the
direction of the appended arrows.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0066] The invention will now be described with reference to the
preferred embodiment shown in FIG. 1. FIG. 1 is an exploded
perspective view of a preferred embodiment of a midsole 103 and an
outsole 105 of the shoe. The outsole 105 is not part of the midsole
103. As shown in FIGS. 1, 2 and 2A, the outsole 105 is below the
midsole 103 when the shoe is in its normal, upright position. This
normal, upright position is shown with respect to the ground 100 in
FIGS. 5A-5D. As used herein, "above" and "below" refer to relative
locations of identified elements when the shoe is in this normal,
upright position as shown in FIGS. 5A-5D. The midsole 103 is
located between the shoe upper 106 and the outsole 105.
[0067] The midsole 103, as shown in FIGS. 1, 2 and 2A, comprises an
upper layer 107, a shank 111, and a lower layer 109. The upper
layer 107 and/or the lower layer 109 may each comprise two or more
sub-layers. As described more fully hereinafter in an alternative
embodiment, the upper layer 107 may also be eliminated
completely.
[0068] In the preferred embodiment shown in FIGS. 1, 2 and 2A,
upper layer 107 has a top surface 113 substantially opposite a
bottom surface 115. Top surface 113 is shown in FIG. 6A. Bottom
surface 115 is shown in FIG. 6B. The shank 111 has a top surface
181 substantially opposite a bottom surface 183. Top surface 181 is
shown in FIG. 6C and bottom surface 183 is shown in FIG. 6D. The
shank has a top portion 186 and a bottom portion 187. Top portion
186 and bottom portion 187 are shown in FIG. 3. The lower layer 109
has a top surface 117 substantially opposite a bottom surface 121.
Top surface 117 is shown in FIG. 6E. Bottom surface 121 is shown in
FIG. 6F. The outsole 105 has a top surface 119 substantially
opposite a bottom surface 123. As shown in FIG. 1, when the shoe is
in its normal, upright position, the shank 111 is below the upper
layer 107. The lower layer 109 is below the shank 111, and the
outsole 105 is below the lower layer 109.
[0069] FIG. 2 is a side elevation view of an embodiment of the
midsole and outsole of the shoe. The shoe has a front tip 140
located at the farthest point toward the front of the shoe and a
rear tip 142 located at the farthest point toward the rear of the
shoe. The upper layer 107 includes a toe region 151 that extends
substantially from the medial side of the shoe to the lateral side
of the shoe at a location that begins in the vicinity of the front
tip 140 and extends from there to a location that is approximately
one third of the distance toward the rear tip 142. The shank 111
includes a toe region 251 that extends substantially from the
medial side of the shoe to the lateral side of the shoe at a
location that begins in the vicinity of the front tip 140 and
extends from there to a location that is approximately one third of
the distance toward the rear tip 142. The lower layer 109 includes
a toe region 161 that extends substantially from the medial side of
the shoe to the lateral side of the shoe at a location that begins
in the vicinity of the front tip 140 and extends from there to a
location that is approximately one third of the distance toward the
rear tip 142. The outsole 105 includes a toe region 171 that
extends substantially from the medial side of the shoe to the
lateral side of the shoe at a location that begins in the vicinity
of the front tip 140 and extends from there to a location that is
approximately one third of the distance toward the rear tip
142.
[0070] The upper layer 107 includes a heel region 153 that extends
substantially from the medial side of the shoe to the lateral side
of the shoe at a location that begins in the vicinity of the rear
tip 142 and extends from there to a location that is approximately
one third of the distance toward the front tip 140. The shank 111
includes a heel region 253 that extends substantially from the
medial side of the shoe to the lateral side of the shoe at a
location that begins in the vicinity of the rear tip 142 and
extends from there to a location that is approximately one third of
the distance toward the front tip 140. The lower layer 109 includes
a heel region 163 that extends substantially from the medial side
of the shoe to the lateral side of the shoe at a location that
begins in the vicinity of the rear tip 142 and extends from there
to a location that is approximately one third of the distance
toward the front tip 140. The outsole 105 includes a heel region
173 that extends substantially from the medial side of the shoe to
the lateral side of the shoe at a location that begins in the
vicinity of the rear tip 142 and extends from there to a location
that is approximately one third of the distance toward the front
tip 140.
[0071] The upper layer 107 includes a middle region 152 that
extends substantially from the medial side of the shoe to the
lateral side of the shoe at a location that extends approximately
between the toe region 151 and the heel region 153. The shank 111
includes a middle region 262 that extends substantially from the
medial side of the shoe to the lateral side of the shoe at a
location that extends approximately between the toe region 251 and
the heel region 253. The lower layer 109 includes a middle region
162 that extends substantially from the medial side of the shoe to
the lateral side of the shoe at a location that extends
approximately between the toe region 161 and the heel region 163.
The outsole 105 includes a middle region 172 that extends
substantially from the medial side of the shoe to the lateral side
of the shoe at a location that extends approximately between the
toe region 171 and the heel region 173.
[0072] Typically, the lower layer 109 of the midsole 103 is on
average thicker in the heel region 163 than it is in the toe region
161. The upper layer 107 has a first density. The lower layer 109
has a second density different from the first density and is
typically less dense than the first density. The upper layer 107
has a first compressibility and the lower layer 109 has a second
compressibility that is different from the first compressibility.
The compressibility of the lower layer 109 is typically relatively
high. Due to this relatively high compressibility, the lower layer
109 undergoes a relatively high amount of deformation when
subjected to a given load. The upper layer 107 is typically made
from polyurethane, polyvinyl chloride, rubber or thermal plastic
rubber. However, the upper layer 107 can be made from any other
material without departing from the scope of the present invention.
Typically the upper layer 107 will have a durometer hardness
between about 45 and about 65 on the Asker C scale.
[0073] FIG. 2A is an exploded side elevation view of FIG. 2. The
lower layer 109 is made of a compressible and deformable yet
resilient material which may or may not be the same material of
which the upper layer 107 is made. Typically the lower layer 109
will have a durometer hardness between about 20 and about 45 on the
Asker C scale. The top surface 113 of the upper layer 107 is
typically positioned below an insole board (not shown) which is
typically positioned below a sockliner (not shown). As shown in
FIGS. 2 and 2A, the bottom surface 115 of the upper layer 107 is in
substantially continuous contact with the top surface 181 of the
shank 111. Due to this substantially continuous contact between the
bottom surface 115 of the upper layer 107 and top surface 181 of
the shank 111 in this embodiment, bottom surface 115 of the upper
layer 107 substantially conforms to top surface 181 of the shank
111. In other embodiments, such substantially continuous contact
between bottom surface 115 of the upper layer 107 and top surface
181 of the shank 111 may not be present. The upper layer 107 has a
bottom surface 115 that may be connected to the top surface 181 of
the shank 111 by either friction and/or an adhesive and/or other
similar means. Alternatively, substantially the entire bottom
surface 115 of the upper layer 107 may be molded to substantially
the entire top surface 181 of the shank 111. Alternatively, the
upper layer may be eliminated in alternative embodiments.
[0074] The shank 111 has a frontmost point 250 and a rearmost point
255. The shank 111 can be made from polyurethane, polyvinyl
chloride, rubber, thermal plastic rubber, carbon fiber or carbon
fiber reinforced plastic. However, the shank 111 can be made from
any other material without departing from the scope of the present
invention. Typically the shank 111 will have a durometer hardness
between about 50 and about 70 on the Shore D scale.
[0075] The outsole 105 typically curves upwardly in the heel
region. The outsole 105 has a frontmost point 170 and a rearmost
point 174. When the shoe is in its typical upright, unloaded state,
the frontmost point 170 and the rearmost point 174 are both
relatively high above the ground 100. From a point at or near the
vicinity of the frontmost point 170, the outsole 105 has a gradual
downward curve 195 that continues through at least a portion of the
toe region 171 of the outsole 105. Starting in the middle region
172, the outsole 105 has a gradual, upward curve 196 that continues
to curve upward through at least a portion of the heel region 173
of the outsole 105. This gradual upward curve 196 typically
continues until the outsole 105 approaches the vicinity of the rear
tip 142 of the shoe. This upward curve 196 is typically sharper
than downward curve 195 in the toe region 171. Upward curve 196 may
be substantially sharper than shown in FIG. 2A or substantially
shallower than shown in FIG. 2A. The outsole 105 has a bottom
surface 123 that typically contains grooves and/or patterns for
optimal traction and wear.
[0076] FIG. 3 is a side elevation view of a preferred embodiment of
the shank 111. In the preferred embodiment, the shank 111 comprises
a top portion 186 and a bottom portion 187. The shank 111 has a top
surface 181 and a bottom surface 183. The bottom surface 183 of the
shank 111 has a longitudinal concavity 303, a longitudinal
convexity 305 and another longitudinal concavity 307.
[0077] The bottom surface 183 of the shank 111 has a longitudinal
concavity 303 that comprises at least a downward curve 190 located
in at least a portion of the heel region 253. "Downward curve," as
used here and throughout this specification, unless otherwise
noted, refers to a direction that moves toward the ground 100 from
any specified location on the shoe when the shoe is oriented in its
typical upright position in which the bottom surface 123 of the
outsole 105 is in unloaded contact with the ground 100.
[0078] The shank 111 has a frontmost point 250 and a rearmost point
255. Downward curve 190 of the longitudinal concavity 303 begins at
or near the vicinity of, the rearmost point 255 of the shank 111
and gradually and continuously descends downwardly from there
through a point at or near the vicinity of the middle region 262.
The portion of the shank 111 indicated by lines extending from, and
associated with, reference numeral 303 indicates the approximate
range wherein longitudinal concavity 303 is typically primarily
located. Longitudinal concavity 303 may, or may not, be entirely
located within the range indicated by the lines extending from, and
associated with, reference numeral 303. Longitudinal concavity 303,
as shown in FIG. 2A, is relatively shallow due to its large radius
of curvature or radii of curvature. Longitudinal concavity 303 may
comprise a curve or curves in addition to downward curve 190. The
radius of curvature throughout longitudinal concavity 303 may be
completely constant, may have one or more constant portions mixed
with one or more non-constant portions, or may be completely
non-constant. Downward curve 190, as well as any other curve or
curves that are part of longitudinal concavity 303, may, at any
point on any of those curves, have a slope that is gradual,
moderate or steep. Although downward curve 190 of longitudinal
concavity 303 is shown in FIG. 2A as beginning near the rearmost
point 255, downward curve 190 of longitudinal concavity 303 may
instead begin at some other location on the bottom surface 183 of
the shank 111. Although longitudinal concavity 303 is shown in FIG.
2A as ending at a location in the middle region 262 or the location
where the heel region 253 transitions into the middle region 262,
longitudinal concavity 303 may end at some other location on the
bottom surface 183 of the shank 111.
[0079] The bottom surface 183 of the shank 111, as shown in FIG.
2A, has a longitudinal concavity 307 that comprises at least an
upward curve 192 located in at least a portion of the middle region
262. "Upward curve," as used here and throughout this
specification, unless otherwise noted, refers to a direction that
moves away from the ground 100 from any specified location on the
shoe when the shoe is oriented in its typical upright position in
which the bottom surface 123 of the outsole 105 is in unloaded
contact with the ground 100.
[0080] Upward curve 192 of longitudinal concavity 307 begins at, or
near the vicinity of the middle region 262 of the bottom surface
183 and gradually and continuously ascends upwardly from there
through at least a portion of the toe region 251. The portion of
the bottom surface 183 indicated by lines extending from, and
associated with reference numeral 307 indicates the approximate
range wherein longitudinal concavity 307 is typically primarily
located. Longitudinal concavity 307 may, or may not, be entirely
located within the range indicated by the lines extending from, and
associated with, reference numeral 307. Longitudinal concavity 307,
as shown in FIG. 2A, is relatively shallow due to its large radius
of curvature or radii of curvature. Longitudinal concavity 307 may
comprise a curve or curves in addition to upward curve 192. The
radius of curvature throughout longitudinal concavity 307 may be
completely constant, may have one or more constant portions mixed
with one or more non-constant portions, or may be completely
non-constant. Upward curve 192, as well as any other curve or
curves that are part of longitudinal concavity 307, may, at any
point on any of those curves, have a slope that is gradual,
moderate or steep. Although upward curve 192 of longitudinal
concavity 307 is shown in FIG. 2A as beginning near the middle
region 262, upward curve 192 of longitudinal concavity 307 may
instead begin at some other location on the bottom surface 183.
Although longitudinal concavity 307 is shown in FIG. 2A as ending
at a location in the toe region 251, longitudinal concavity 307 may
end at some other location on the bottom surface 183 of the shank
111.
[0081] The bottom surface 183 of the shank 111, as shown in FIG.
2A, has a longitudinal convexity 305 that is defined by downward
curve 190 and upward curve 192 and that is typically located in at
least a portion of the middle region 262.
[0082] Longitudinal convexity 305 may, or may not, be entirely
located within the range indicated by the lines extending from, and
associated with, reference numeral 305. Longitudinal convexity 305,
as shown in FIG. 2A, is relatively shallow due to its large radius
of curvature or radii of curvature. Longitudinal convexity 305 may
comprise a curve or curves in addition to upward curve 192 and
downward curve 190. The radius of curvature throughout longitudinal
convexity 305 may be completely constant, may have one or more
constant portions mixed with one or more non-constant portions, or
may be completely non-constant. Downward curve 190 and upward curve
192, as well as any other curve or curves that are part of
longitudinal convexity 305, may, at any point on any of those
curves, have a slope that is gradual, moderate or steep. Although
longitudinal convexity 305 is shown in FIG. 2A as ending at a
location where the middle region 162 transitions into the toe
region 161, longitudinal convexity 305 may end at some other
location on the bottom surface 183 of the shank 111.
[0083] The shank 111, has a cavity 309 which is formed by the top
portion 186 and bottom portion 187. The cavity has a beginning
point 311 and an end point 313. The cavity 309 begins at the
beginning point 311 longitudinally closer to the heel region. The
cavity 309 terminates at end point 313 closer to the middle region.
The shank 111 has a bottom surface 183 that may be connected to the
top surface 117 of the bottom layer 109 by either friction and/or
an adhesive and/or other similar means. Alternatively,
substantially the entire bottom surface 183 of the shank 111 may be
molded to substantially the entire top surface of the bottom layer
109. As shown in FIGS. 2 and 2A, the top surface 117 of the lower
layer 109 is in substantially continuous contact with the bottom
surface 183 of the shank 111. Due to this substantially continuous
contact between the top surface 117 of the lower layer 109 and
bottom surface 183 of the shank 111 in this embodiment, top surface
117 of the lower layer 109 substantially conforms to bottom surface
183 of the shank 111. In other embodiments, such substantially
continuous contact between top surface 117 of the lower layer 109
and bottom surface 183 of the shank 111 may not be present.
[0084] FIG. 3A is a front elevation view in cross section of an
embodiment of the shank 111 along line 3A-3A in the direction of
the appended arrows. As shown, the bottom surface 183 of the shank
111 along line 3A-3A is straight.
[0085] FIG. 3B is a front elevation view in cross section of an
alternative embodiment of the shank 111 along line 3A-3A in the
direction of the appended arrows. As shown, the bottom surface 183
of the shank 111 along line 3A-3A contains a transverse
concavity.
[0086] FIG. 3C is a front elevation view in cross section of
another alternative embodiment of the shank 111 along line 3A-3A in
the direction of the appended arrows. As shown, the bottom surface
183 of the shank 111 along line 3A-3A contains a transverse
convexity.
[0087] FIG. 4 is a perspective view of a preferred embodiment of
the shank 111 as seen in FIGS. 1, 2, 2A and 3. FIG. 4 illustrates
the cavity 309 being open from the lateral to medial side of the
shoe.
[0088] In normal use of the shoe, each forward step taken by the
user begins when the heel region 173 of the outsole 105 begins to
make contact with the ground 100. The lower layer 109 of the
midsole 103 in the heel region 163 that is made of less dense and
more readily compressible material then begins to compress and
deform, allowing the heel of the user's foot to sink toward the
ground 100 to a greater extent than it would sink while wearing a
conventional shoe. Due to longitudinal concavity 303, the lower
layer 109 is relatively thick in the heel region 163. Since this
relatively thick heel region 163 of the lower layer 109 is also
relatively soft and highly compressible, it mimics the effect of
walking or running on a sandy beach, thereby requiring the user to
exert more energy while walking or running than would be required
when walking or running while wearing conventional shoes.
Additionally, since the heel region 163 of the lower layer 109 is
relatively thick and highly compressible, it has a degree of
inherent longitudinal and transverse instability that is not
present in conventional shoes. This inherent instability forces the
user to engage in a balancing effort and use muscles and muscle
control and coordination to maintain a normal walking gait that
would not be required with conventional shoes. However, while also
maintaining an inherent instability due to the lower layer 109 as
discussed above, the shank 111, due to its rigidity and structure
is able to provide proper support to the user's heel so that
although the heel region 163 compresses and provides instability,
the shank 111 provides stability and does not compress.
[0089] As the step continues, the user's weight shifts to the
middle regions 152, 162, 262, and 172 and the shoe rolls forward in
a smooth motion without the user having to overcome any abrupt
pivot point. The lower layer 109 of the midsole 103 in the middle
region 162 then compresses and deforms, allowing the user's foot in
that region to sink toward the ground 100 more than it would sink
if the user were wearing conventional shoes, due to the inherent
instability due to the lower layer 109 as discussed above. As with
the above, the shank 111, due to its rigidity and structure is able
to provide proper support to the user's midfoot area. The cavity
309 in the shank 111, may cause the bottom portion 187 of the shank
111 to compress a small amount in the area directly below the
cavity 309. This compression provides cushioning and imparts some
instability, but the shank 111 still maintains adequate support to
the user's foot.
[0090] As the step continues, the user's weight then shifts to the
toe regions 151, 161, 251, and 171. The lower layer 109 of the
midsole 103 in the toe region 161 then compresses and deforms,
allowing the user's foot in that region to sink toward the ground
100 more than it would sink if the user were wearing conventional
shoes. As shown in FIG. 2A, the thickness of the lower layer 109 in
the toe region 161 is typically not as great as it is in the heel
region 163. This decrease in thickness of the lower layer 109
results in relatively more stability in the toe region 161. This
allows the user, when completing his/her step more control when
pushing off with the forefoot ball of the user's foot.
[0091] All of this simulates the effect, and imparts the fitness
benefits, of running or walking on a sandy beach or on a giving or
uneven soft surface regardless of the actual hardness of the
surface.
[0092] FIGS. 5A-5D show a side elevation exterior view of a
representative shoe that embodies the instant invention. FIG. 5A
shows this representative shoe in a fully unloaded state. FIGS. 5B,
5C, and 5D show this representative shoe undergoing normal loading
that occurs when a user walks or runs while wearing the shoe. In
FIGS. 5A-5D, the shank 111 does not undergo a significant amount of
compression aside from the area occupied by cavity 309. Thus the
compression of the shank is not shown aside from the area occupied
by cavity 309.
[0093] In FIGS. 5A-5D, the straight lines identified by,
respectively, reference numerals 501A-501D, 502A-502D, and
503A-503D each represent the thickness of the upper layer 107 at
the location where each such straight line 501A-501D, 502A-502D,
and 503A-503D appears. The straight lines identified by,
respectively, reference numerals 504A-504D, 505A-505D, and
506A-506D each represent the thickness of the lower layer 109 at
the location where each such straight line 504A-504D, 505A-505D,
and 506A-506D appears. The straight lines identified by,
respectively, reference numerals 509A-509D each represent the area
occupied by the cavity 309. A decrease in the area represented by
numeral 509A-509D represents a compression in the cavity 309 of
shank 111.
[0094] As shown in the unloaded state in FIG. 5A, the upper layer
107 and lower layer 109 are not undergoing any compression. As also
shown in FIG. 5A, the outsole 105 is not undergoing any deflection
or deformation. In this fully uncompressed state, the thickness of
the upper layer 107 and the thickness of the lower layer 109 are
each at their respective maximum thickness. This maximum thickness
is indicated by, and corresponds to, the length of each straight
line 501A-506A, each one of which is at its maximum length as shown
in FIG. 5A. Furthermore, the area occupied by the cavity is at its
maximum. This maximum area is indicated by and corresponds to the
length of the straight line 509A.
[0095] FIG. 5B shows the representative shoe in an orientation
where the user's heel (not shown) is imparting a load in the heel
regions 153, 163, 253, and 173, shown in FIGS. 1 and 2. In normal
use of the shoe, each forward step taken by the user begins when
the heel region 173 of the outsole 105 begins to make contact with
the ground 100. The lower layer 109 of the midsole 103 in the heel
region 163 that is made of less dense and more readily compressible
material then begins to compress and deform, allowing the heel of
the user's foot to sink toward the ground 100 to a greater extent
than it would sink while wearing a conventional shoe. Due to
longitudinal concavity 303, the lower layer 109 is relatively thick
in the heel region 163. Since this relatively thick heel region 163
of the lower layer 109 is also relatively soft and highly
compressible, it mimics the effect of walking or running on a sandy
beach, thereby requiring the user to exert more energy during use
than would be required with conventional shoes. Additionally, since
the heel region 163 of the lower layer 109 is relatively thick and
highly compressible, it has a degree of inherent longitudinal and
transverse instability that is not present in conventional shoes.
This inherent instability forces the user to engage in a balancing
effort and use muscles and muscle control and coordination to
maintain a normal gait that would not be required with conventional
shoes. However, while also maintaining an inherent instability due
to the lower layer 109 as discussed above, the shank 111, due to
its rigidity and structure is able to provide proper support to the
user's heel so that although the heel region 163 compresses and
provides instability, the shank 111 provides stability and does not
compress. Under this loading condition, the heel region 153 of the
upper layer 107 is undergoing a relatively small amount of
compression. This relatively small amount of compression results in
a relatively small decrease in the thickness of the heel region 153
of the upper layer 107. This relatively small decrease in thickness
is indicated by 501 B. Under this same loading, the heel region 163
of the lower layer 109 is undergoing a relatively large amount of
compression. This relatively large amount of compression results in
a relatively large decrease in the thickness of the heel region 163
of the lower layer 109. This relatively large decrease in thickness
is indicated by 504B. Under this same loading, the heel region 173
of the outsole 105 is undergoing a relatively large amount of
deflection. This relatively large amount of deflection in the heel
region 173 of the outsole 105 is caused by the heel region 173
conforming to the ground 100 as it bears the load of the user. This
deflection and conformity of the heel region 173 of the outsole 105
is indicated by the straight portion of the outsole 105 where it
contacts the ground 100 as shown in FIG. 5B.
[0096] FIG. 5C shows the representative shoe in an orientation
where the user's foot (not shown) is imparting a load in the middle
regions 152, 162, 262, and 172, shown in FIGS. 1 and 2. As the step
continues, the user's weight shifts to the middle regions 152, 162,
262, and 172 and the shoe rolls forward in a smooth motion without
the user having to overcome any abrupt pivot point. The lower layer
109 of the midsole 103 in the middle region 162 then compresses and
deforms, allowing the user's foot in that region to sink toward the
ground 100 more than it would sink if the user were wearing
conventional shoes, due to the inherent instability due to the
lower layer 109 as discussed above. As with the above, the shank
111, due to its rigidity and structure is able to provide proper
support to the user's midfoot region. The cavity 309 in the shank
111, may cause the bottom portion 187 of the shank 111 to compress
a small amount in the area directly below the cavity 309. That
compression provides cushioning and imparts some instability, but
the shank 111 still maintains adequate support to the user's foot.
Under this loading condition, the middle region 152 of the upper
layer 107 is undergoing a relatively small amount of compression.
This relatively small amount of compression results in a relatively
small decrease in the thickness of the middle region 152 of the
upper layer 107. This relatively small decrease in thickness is
indicated by 502C. Under this same loading, the middle region 162
of the lower layer 109 is undergoing a relatively large amount of
compression. This relatively large amount of compression results in
a relatively large decrease in the thickness of the middle region
162 of the lower layer 109. This relatively large decrease in
thickness is indicated by 505C. Under this same loading, the middle
region 172 of the outsole 105 is undergoing a relatively large
amount of deflection. This relatively large amount of deflection in
the middle region 172 of the outsole 105 is caused by the middle
region 172 conforming to the ground 100 as it bears the load of the
user. This deflection and conformity of the middle region 172 of
the outsole 105 is indicated by the straight portion of the outsole
105 where it contacts the ground 100 as shown in FIG. 5C.
Furthermore, the area occupied by the cavity 309 is decreased due
to the weight of the user's foot with respect to the ground. The
decrease in area of cavity 309 is shown in line 509C.
[0097] FIG. 5D shows the representative shoe in an orientation
where the user's foot (not shown) is imparting a load in the toe
regions 151, 161, 251, and 171, shown in FIGS. 1 and 2. As the step
continues, the user's weight then shifts to the toe regions 151,
161, 251, and 171. The lower layer 109 of the midsole 103 in the
toe region 161 then compresses and deforms, allowing the user's
foot in that region to sink toward the ground 100 more than it
would sink if the user were wearing conventional shoes. As shown in
FIG. 2A, the thickness of the lower layer 109 in the toe region 161
is typically not as great as it is in the heel region 163. This
decrease in thickness of the lower layer 109 results in relatively
more stability in the toe region 161. This allows the user, when
completing his/her step more control when pushing off with the
forefoot ball of the user's foot. Under this loading condition, the
toe region 151 of the upper layer 107 is undergoing a relatively
small amount of compression. This relatively small amount of
compression results in a relatively small decrease in the thickness
of the toe region 151 of the upper layer 107. This relatively small
decrease in thickness is indicated by 503D. Under this same
loading, the toe region 161 of the lower layer 109 is undergoing a
relatively large amount of compression. This relatively large
amount of compression results in a relatively large decrease in the
thickness of the toe region 161 of the lower layer 109. This
relatively large decrease in thickness is indicated by 506D. Under
this same loading, the toe region 171 of the outsole 105 is
undergoing a relatively large amount of deflection. This relatively
large amount of deflection in the toe region 171 of the outsole 105
is caused by the toe region 171 conforming to the ground 100 as it
bears the load of the user. This deflection and conformity of the
toe region 171 of the outsole 105 is indicated by the straight
portion of the outsole 105 where it contacts the ground 100 as
shown in FIG. 5D. The area in the cavity 309 is now returned to its
original state as shown in line 509D, which is equal to line
509A.
[0098] FIGS. 7, 8 and 8A show another embodiment of the invention.
The midsole 703 in this alternative embodiment does not have an
upper layer but rather is comprised of a shank 711 and a lower
layer 709. The lower layer 709 can be comprised of two or more
sub-layers.
[0099] In this alternative embodiment, lower layer 709 has a top
surface 717 substantially opposite a bottom surface 721. The shank
711 has a top surface 781 substantially opposite a bottom surface
783. The shank has a top portion 786 and a bottom portion 787
similar to the embodiment of shank 111 shown in FIG. 3. The outsole
705, which is not part of the midsole 703, has a top surface 719
substantially opposite a bottom surface 723. As shown in FIG. 7,
when the shoe is in its normal, upright position, the lower layer
709 is below the shank 711 and the outsole 705 is below the lower
layer 709.
[0100] FIG. 8 is a side elevation view of the alternative
embodiment. The shoe has a front tip 740 located at the farthest
point toward the front of the shoe and a rear tip 742 located at
the farthest point toward the rear of the shoe. The shank 711
includes a toe region 851 that extends substantially from the
medial side of the shoe to the lateral side of the shoe at a
location that begins in the vicinity of the front tip 740 and
extends from there to a location that is approximately one third of
the distance toward the rear tip 742. The lower layer 709 includes
a toe region 761 that extends substantially from the medial side of
the shoe to the lateral side of the shoe at a location that begins
in the vicinity of the front tip 740 and extends from there to a
location that is approximately one third of the distance toward the
rear tip 742. The outsole 705 includes a toe region 771 that
extends substantially from the medial side of the shoe to the
lateral side of the shoe at a location that begins in the vicinity
of the front tip 740 and extends from there to a location that is
approximately one third of the distance toward the rear tip
742.
[0101] The shank 711 includes a heel region 853 that extends
substantially from the medial side of the shoe to the lateral side
of the shoe at a location that begins in the vicinity of the rear
tip 742 and extends from there to a location that is approximately
one third of the distance toward the front tip 740. The lower layer
709 includes a heel region 763 that extends substantially from the
medial side of the shoe to the lateral side of the shoe at a
location that begins in the vicinity of the rear tip 742 and
extends from there to a location that is approximately one third of
the distance toward the front tip 740. The outsole 705 includes a
heel region 773 that extends substantially from the medial side of
the shoe to the lateral side of the shoe at a location that begins
in the vicinity of the rear tip 742 and extends from there to a
location that is approximately one third of the distance toward the
front tip 740.
[0102] The shank 711 includes a middle region 862 that extends
substantially from the medial side of the shoe to the lateral side
of the shoe at a location that extends approximately between the
toe region 851 and the heel region 853. The lower layer 709
includes a middle region 762 that extends substantially from the
medial side of the shoe to the lateral side of the shoe at a
location that extends approximately between the toe region 761 and
the heel region 763. The outsole 705 includes a middle region 772
that extends substantially from the medial side of the shoe to the
lateral side of the shoe at a location that extends approximately
between the toe region 771 and the heel region 773.
[0103] FIG. 8A is an exploded side elevation view of FIG. 8. The
lower layer 709 is made of a compressible and deformable yet
resilient material. Typically the lower layer 709 will have a
durometer hardness between about 20 and about 45 on the Asker C
scale. The top surface 781 of the shank 711 is typically positioned
below an insole board (not shown) which is typically positioned
below a sockliner (not shown). As shown in FIGS. 8 and 8A, top
surface 717 of the lower layer 709 is in substantially continuous
contact with, and substantially conforms to, the bottom surface 783
of the shank 711. In other embodiments, such substantially
continuous contact between top surface 717 and bottom surface 783
may not be present.
[0104] The bottom surface 783 of the shank 711, as shown in FIG.
8A, has a longitudinal concavity 782 that comprises at least a
downward curve 790 located in at least a portion of the heel region
853.
[0105] The shank 711 has a frontmost point 750 and a rearmost point
755. Downward curve 790 of longitudinal concavity 782 begins at, or
near the vicinity of, the rearmost point 755 of the shank 711 and
gradually and continuously descends downwardly from there through a
point at or near the vicinity of the middle region 862. The portion
of the bottom surface 783 of the shank 711 indicated by lines
extending from, and associated with, reference numeral 782
indicates the approximate range wherein longitudinal concavity 782
is typically primarily located. Longitudinal concavity 782 may, or
may not, be entirely located within the range indicated by the
lines extending from, and associated with, reference numeral 782.
Longitudinal concavity 782, as shown in FIG. 8A, is relatively
shallow due to its large radius of curvature or radii of curvature.
Longitudinal concavity 782 may comprise a curve or curves in
addition to downward curve 790. The radius of curvature throughout
longitudinal concavity 782 may be completely constant, may have one
or more constant portions mixed with one or more non-constant
portions, or may be completely non-constant. Downward curve 790, as
well as any other curve or curves that are part of longitudinal
concavity 782, may, at any point on any of those curves, have a
slope that is gradual, moderate or steep. Although downward curve
790 of longitudinal concavity 782 is shown in FIG. 8A as beginning
near the rearmost point 774, downward curve 790 of longitudinal
concavity 782 may instead begin at some other location on the shank
711. Although longitudinal concavity 782 is shown in FIG. 8A as
ending at a location in the middle region 862 or the location where
the heel region 853 transitions into the middle region 862,
longitudinal concavity 782 may end at some other location on the
bottom surface 783 of the shank 711.
[0106] The bottom surface 783 of the shank 711, as shown in FIG.
8A, has a longitudinal concavity 785 that comprises at least an
upward curve 792 located in at least a portion of the middle region
862. Upward curve 792 of longitudinal concavity 785 begins at, or
near the vicinity of, the middle region 862 of the lower layer 709
and gradually and continuously ascends upwardly from there through
at least a portion of the toe region 851. The portion of the bottom
surface 783 of the shank 711 indicated by lines extending from, and
associated with, reference numeral 785 indicates the approximate
range wherein longitudinal concavity 785 is typically primarily
located. Longitudinal concavity 785 may, or may not, be entirely
located within the range indicated by the lines extending from, and
associated with, reference numeral 785. Longitudinal concavity 785,
as shown in FIG. 8A, is relatively shallow due to its large radius
of curvature or radii of curvature. Longitudinal concavity 785 may
comprise a curve or curves in addition to upward curve 792. The
radius of curvature throughout longitudinal concavity 785 may be
completely constant, may have one or more constant portions mixed
with one or more non-constant portions, or may be completely
non-constant. Upward curve 792, as well as any other curve or
curves that are part of longitudinal concavity 785, may, at any
point on any of those curves, have a slope that is gradual,
moderate or steep. Although upward curve 792 of longitudinal
concavity 785 is shown in FIG. 8A as beginning near the middle
region 762, upward curve 792 of longitudinal concavity 785 may
instead begin at some other location on the bottom surface 783 of
the shank 711. Although longitudinal concavity 785 is shown in FIG.
8A as ending at a location in the toe region 851, longitudinal
concavity 785 may end at some other location on the bottom surface
783 of the shank 711.
[0107] The bottom surface 783 of the shank 711, as shown in FIG.
8A, has a longitudinal convexity 789 that comprises the downward
curve 790 and upward curve 792 and that is typically located in at
least a portion of the middle region 862. Longitudinal convexity
789 may, or may not, be entirely located within the range indicated
by the lines extending from, and associated with, reference numeral
789. Longitudinal convexity 789, as shown in FIG. 8A, is relatively
shallow due to its large radius of curvature or radii of curvature.
Longitudinal convexity 789 may comprise a curve or curves in
addition to upward curve 792 and downward curve 790. The radius of
curvature throughout longitudinal convexity 789 may be completely
constant, may have one or more constant portions mixed with one or
more non-constant portions, or may be completely non-constant.
Downward curve 790 and upward curve 792, as well as any other curve
or curves that are part of longitudinal convexity 789, may, at any
point on any of those curves, have a slope that is gradual,
moderate or steep. Although longitudinal convexity 789 is shown in
FIG. 8A as ending at a location where the middle region 762
transitions into the toe region 761, longitudinal convexity 789 may
end at some other location on the bottom surface 783 of the shank
711.
[0108] As shown in FIGS. 8 and 8A, the outsole 705 typically curves
upwardly in the heel region. The outsole 705 has a frontmost point
770 and a rearmost point 774. When the shoe is in its typical
upright, unloaded state, the frontmost point 770 and the rearmost
point 774 are both relatively high above the ground 100. From a
point at or near the vicinity of the frontmost point 770, the
outsole 705 has a gradual downward curve 795 that continues through
at least a portion of the toe region 771 of the outsole 705.
Starting in the middle region 772, the outsole 705 has a gradual,
upward curve 796 that continues to curve upward through at least a
portion of the heel region 773 of the outsole 705. This gradual
upward curve 796 typically continues until the outsole 705
approaches the vicinity of the rear tip 742 of the shoe. This
upward curve 796 is typically sharper than downward curve 795 in
the toe region 771. Upward curve 796 may be substantially sharper
than shown in FIG. 8A or substantially shallower than shown in FIG.
8A.
[0109] FIG. 9A depicts a top plan view of the top surface of an
alternative embodiment of a shank 901 along line 6C-6C in the
direction of the appended arrows. As shown, the shank 901 shown in
FIG. 9A differs from the shank 111 shown in FIG. 6C. The shank 901,
instead of having a fork-like structure as shown in 6C, does not
have any open areas and occupies substantially all of the area from
the medial to the lateral side of the shoe between the rear tip 142
and the front tip 140.
[0110] FIG. 9B depicts a top plan view of the top surface of
another alternative embodiment of a shank 903 along line 6C-6C in
the direction of the appended arrows. As shown, the shank 903 shown
in FIG. 9B differs from the shank 111 shown in FIG. 6C. The shank
903, instead of extending from the rear tip 142 to the front tip
140, extends only from the rear tip 142 to an area close to the
middle region 262 and does not extend to the front tip 140.
[0111] While the foregoing detailed description sets forth selected
embodiments of a shoe in accordance with the present invention, the
above description is illustrative only and not limiting of the
disclosed invention. The claims that follow herein collectively
cover the foregoing embodiments. The following claims further
encompass additional embodiments that are within the scope and
spirit of the present invention.
* * * * *