SPLIT-SOLE FOOTWEAR
RELATED APPLICATION
The t application claims priority to United States Patent Application No.
13/207,397, filed August 10, 2011, entitled “Split-Sole Footwear”.
FIELD OF THE DISCLOSURE
The present sure relates to footwear and more specifically, split-sole shoes.
BACKGROUND
Conventional footwear has ural limitations that force the wearer to make lt
choices between style and comfort. As a result, many duals endure significant foot pain,
or elect to wear less attractive shoes or styles that may not be appropriate for the occasion. To
address this problem, some women carry additional footwear in a car or large bag. However, a
spare pair of conventional shoes is less than ideal because of size and bulk limitations on
portability. Lightweight rollable or foldable shoes are available that offer increased
portability. r, such ts do not contain the support, durability, comfort or style
desired in a non—foldable shoe.
Moreover, prior art foldable shoes have outsoles that do not adequately protect the
shoe midsole and upper, g to premature wear of the shoe including tearing and damage
to the shoe. Furthermore, such shoes are lly flimsy or, in other words, do not provide
adequate t or tion of the foot. For instance, many foldable shoes have an overall
spring constant that is, depending on the brand and model, between 0.14 kilogram-force / inch
and 0.34 kilogram-force / inch. Such shoes provide little or no resistance, protection and
support, and thus are inadequate to wear for repeated or extended use, particularly outside or
on rough terrain (e.g., dirty pavement, stones, eta). Moreover, such shoes are not durable
enough to last a normal shoe lifespan even with only moderate use. Therefore, while some
footwear designs have attempted to bridge the gap between full time and portable shoes, there
remains no practical solution.
In prior art shoe manufacturing processes, outsoles are sewn onto a midsole. These
outsoles are at the bottom of the shoe and protect the midsole and upper from wear and tear
and fiarther e support and rigidity to the entire shoe. After the outsoles have been sewn
on, the midsole is sewn to the upper and an insole thereby forming a single seam. This single
2011/060662
seam traverses the perimeter of the shoe and essentially delineates the shoe upper from the
midsole. While such processes are advantageous e ofmanufacturing efficiencies, the
drawback with such approaches is realized when one considers the properties of the outsoles.
The sewing wheel of the sewing e used to sew the midsole, the upper, and the insole
together interferes with the outsoles previously sewn onto the midsole. As a result, a dilemma
. The ideal e patches serve to 1) protect the foot, 2) provide comfort, and 3)
provide durability by protecting the seam attaching the midsole, outsole and insole. Thus, the
ideal outsole patches are thick and wide such that the perimeter of the es is close to the
seam. Yet, as the outsole becomes thicker and is brought closer to the seam that attaches the
upper, midsole and insole, the seam becomes more difficult and eventually ible to
stitch. Thus, prior art shoes are constructed with either (i) thin and wide or (ii) narrow and
thick outsole patches. Moreover, prior art shoes are limited on their ability to add cushion
inserts below the insole because such cushion inserts make the seam even less manageable and
force more narrowing and thinning of the outsole patches leading to r instability and/or
lower durability of the shoe and protection of the foot. Thus, in prior art shoes, shoe comfort
and durability is traded off for shoe stability. Thus the dilemma become apparent. If the
outsole is made thick and narrow, the lack of support due to the gap between the perimeter of
the es and the seam s noticeable and uncomfortable and the seam, upper and
midsole are left exposed to the ground. If the outsole is made thin and wide, the lack of
support due to the gap between the perimeter of the outsole and the seam is not as noticeable.
However, in such instances, the upper, midsole and seam are exposed to the ground, the
outsole wears more y and the shoe es limited protection and comfort.
Given the above background, what is needed in the art are improved foldable shoe
designs and improved shoe manufacturing processes.
SUMMARY
The present disclosure addresses the preceding and other shortcomings of the prior art
by providing an improved foldable shoe. The disclosed shoes are a split-sole class of
women’s shoe that allows for the shoe to be folded and placed in a drawstring pouch. The
split sole is defined by a heel outsole patch and a toe outsole patch with a spacing between the
patches. Advantageously, the disclosed shoes combine an upper and a midsole at a seam with
an insole added in separately. Thus, the insole is not concurrently stitched into the seam that
joins the midsole to the upper. This allows for (i) the perimeter of the heel outsole patch and
the toe outsole patch to be much closer to the seam g the midsole to the upper, and (ii)
the outsole patches to be thicker, thereby affording better protection of the seam, midsole, and
upper, greater t and comfort to the foot, a more rigid footbed, and allows for the
insertion of thicker more substantial cushioning.
In some embodiments, the outsole patches are sewn on. In some embodiments, the
outsole s are both sewn and glued on. To facilitate sewing the patches on, deep grooves
near the perimeter of each outsole patch are afforded. These deep grooves are used to form
the seam between the patches and the midsole. The thread used to form this seam is better
protected by the deep grooves thereby improving the durability of the shoe and preventing
wear on the seam.
The disclosed shoes have an improved spring constant relative to known shoes in the
women’s split sole class. In some embodiments, the spring constant of the overall shoe is
between 0.40 kilogram-force / inch and 0.70 kilogram-force / inch or between 0.55 kilogram-
force / inch and 0.65 am-force / inch. This improved spring force constant lends greater
support and allows for prolonged periods of wear.
In some embodiments, in addition to ing a foam inlay that is often found in
women’s shoes, the disclosed shoes allow for the insertion of a cushion insert in the heel
portion of the shoes to provide additional support and comfort. Moreover, this heel portion
has greater thickness at the heel end of the shoe than at a position intermediate the heel and toe
ends of the shoes. Such a tapered thickness es additional comfort, support, and style.
While it is known to place an elastic restriction at the edge of the upper that receives a
s foot, the disclosed shoes provide an improved design by terminating the elastic
restriction in the heel n of the shoe. There, rather than using the c restriction, an
embedded cushion (Achilles’ n) is provided in order to provide greater comfort.
BRIEF PTION OF THE DRAWINGS
Figure 1 is a perspective view of a shoe in accordance with an aspect of the disclosure
in which the shoe is in an extended state.
Figure 2 is a side view of a shoe in ance with an aspect of the disclosure in
which the shoe is in an extended state.
Figure 3 is a top view of a shoe in accordance with an aspect of the disclosure in which
the shoe is in an extended state.
Figure 4 is a front view of a shoe in accordance with an aspect of the disclosure in
which the shoe is in an extended state.
Figure 5 is a rear view of a shoe in accordance with an aspect of the disclosure in
which the shoe is in an extended state.
Figure 6 is a cross-sectional side View of a shoe in accordance with an aspect of the
disclosure in which the shoe is in an extended state.
Figure 6A is a sectional view taken about region 6A—6A of Figure 6.
Figure 6B is a cross-sectional view taken about region 6B-6B of Figure 6.
Figure 7 is a perspective View of a shoe in accordance with an aspect of the sure
showing a cushion insert in which the shoe is in an extended state.
Figure 8 is a cutaway perspective view of a shoe in accordance with an aspect of the
disclosure in which the shoe is in an extended state.
Figure 9 is a bottom view of a shoe in accordance with an aspect of the sure in
which the shoe is in an extended state.
Figure 9A is an inset perspective view taken about line 9A-9A of Figure 9.
Figure 9B is an inset sectional view of Figure 9B, taken about line 9B—9B of
Figure 9.
Figure 10 is a compact box having a lid in which a pair of shoes of the t
disclosure can be stored in the folded state.
Figure 11 is a perspective of a shoe in accordance with an aspect of the disclosure in
which the shoe is in a folded state in which the shoe is bent about an axis such that a portion of
an upper comprising a toe cavity is tucked into a heel cavity.
Figure 12 is a perspective view of a drawstring pouch that may be used to store the
shoes of the present disclosure.
Figure 13 is a perspective View of a tote bag that may be used to store shoes and other
items in accordance with the present disclosure
Like reference numerals refer to corresponding parts throughout the several views of
the drawings.
DETAILED DESCRIPTION
Figures 1 through 5 respectively provide perspective, side, top, front and back views of
a shoe in accordance with the disclosure. From the ctive and side views of Figures 1
and 2, and when worn, the shoe appears no different from a tional rigid sole shoe. Yet
the shoe affords lity in design, foldability, and comfort without dressing down the
wearer's outfit. In some embodiments, a n insert s impact to the foot from
walking on hard surfaces. An elastic restriction 60 runs around the top ofthe upper 2 to grip
the foot and form a snug fit on feet of various sizes and shapes. However, the elastic
restriction 60 is designed to not encircle the entire foot, by stopping short in the back where it
would otherwise uncomfortably grip the Achilles tendon area. Instead, an es cushion 56
is embedded in the upper fold that would otherwise surround the elastic restriction 60 to
increase comfort. Moreover, in some embodiments, the Achilles heel portion of the upper 2 is
skived so as to reduce its depth. By skiving this portion of the shoe, the seam that would
normally protrude and come into contact with the foot is d, resulting in greater comfort.
Elastic restriction 60 is affixed to the opening of the upper 2 so that, when worn, the
opening of the upper 2 will stretch to the size of the foot. In some embodiments, the elastic
ction 60 is sewn and glued to the upper 2 so as to most securely affix the two materials.
In some embodiments, the elastic restriction 60 is sewn but not glued to the upper 2. By
sewing the elastic restriction without glue, the maximum amount that the elastic can be
stretched is increased. This allows for a more comfortable fit on more foot sizes. In addition,
by not gluing the elastic the natural rebound rate of the elastic restriction is preserved, adding
comfort and extending the useful life of the elastic.
Referring to Figure 6, a flexible insole 30 provides added t without
mising portability, and may be fixed or removable. Optionally, the flexible insole 30
provides arch t. The shoe further comprises a foam inlay 44 that is affixed by glue to
the insole 30. In some ments, a flexible arch support provides added comfort without
compromising portability. The flexible arch support does not restrict folding of the shoe, and
may be fixed or removable. In some embodiments, the midsole 8 is reinforced by affixing
flexible material on the inside of the midsole, h the insole 30 (e.g, between midsole 8
foam inlay 44). rcement of the midsole 8 in this manner has several benefits. First, the
flex points of the footwear are strengthened without compromising portability. Second, the
portions of the midsole 8 most likely to suffer from destructive friction from contact with the
walking surface are strengthened to better and that stress. Third, the portion of the
midsole 8 that comes in contact with the edge of the toe outsole patch is made more resistant
to tearing. In some embodiments such a reinforcement is in instead of foam inlay 44. In some
embodiments such a reinforcement is in addition to foam inlay 44.
In some embodiments, a rigid insert is inserted in between foam inlay 44 and the
midsole 8. This rigid insert extends the width of the midsole 8, and from the toe of the
midsole 8 to no further than midpoint 32 at which the footwear is folded. By inserting the
rigid insert in this manner, greater space is maintained when worn between the te
portions of the footwear (e.g., upper 2) and the walking surface. By increasing this space,
durability is improved.
Continuing to refer to Figure 6, the shoe ses three uniquely shaped elements: a
midsole 8, a heel outsole patch 24, and a toe outsole patch 26. In some embodiments, the
midsole 8 is made of a flexible but durable al, such as high quality leather. In some
ments, the heel outsole patch 24 and toe outsole patch 26 are constructed from all
weather, non-skid material. In typical embodiments, the heel outsole patch 24 and the toe
outsole patch 26 are individually sewn to the midsole 8. Materials required for the necessary
durability and safety of a full time shoe are too rigid to afford the necessary flexibility to be
folded. Thus, in preferred embodiments, the heel e patch 24 and the toe outsole patch 26
are distinct, and individually ed to the midsole 8 with a spacing 32 between them for the
shoe to be folded. The size and shape of the heel outsole patch 24 and the toe outsole patch 26
are designed to optimally balance durability, comfort, and practicality, with compact size and
minimal weight. The shape of the heel outsole patch 24 and the toe outsole patch 26
maximize protection for the foot in a space efficient manner. In some embodiments, the
contours of the heel outsole patch 24 and the toe outsole patch 26 are sloped to provide
attractive additional height when worn, and increase the nce between the midsole 8 and
the ground when worn. In such embodiments, the slope is designed so that when two shoes
are d, large meets small so as to significantly reduce the ed ess of the
compressed pair for increased portability.
The upper 2 of the shoe is made of a high quality flexible but durable material
designed to withstand repeated folding at the center of the shoe, as well as long periods of
e in the folded position. Such materials reduce or eliminate cracking at the surface of
the joint, and damage from contact with surfaces. The upper 2 is constructed and ed in a
manner to wrap around the top and sides of the foot. The specific proportion of upper to
outsole also allows the soft upper 2 to mold to wide and narrow feet, molding to the unique
shape of each wearer's foot, and adding comfort and style benefits. The proportion also
reduces the bulk of the shoes in the folded state for e and portability. A rounded toe
cavity 6 and flexible ound upper design increases commercial appeal by reducing or
eliminating the need for costly half-size and/or variable width inventory, while maintaining a
e and comfortable design. The design allows great flexibility for fashionable elements
via the upper such as distinctive colors, textures and ornamentation. When worn, the shoe
appears no ent from conventional fixed sole footwear, adding style and the y to be
worn with more formal attire.
Referring to Figure 13, a lightweight, durable, reusable, self-contained collapsible tote
bag with handles that may be folded and compressed, and then stored in the compacting pouch
(Figure 12) adds utility to the foldable shoe system. In typical ments pouch is made
out of a y stretch material and is capable of self—folding into a shape that minimizes
volume (e.g., an approximately spherical shape). In some embodiments, the stitching of the
pouch facilitates this stretching (e.g., using a zigzag stitching). In some ments, a
h thread material is used in such stitching.
Advantageously, the tote bag may be collapsed into a pocket of the tote bag. In some
embodiments, this pocket is in the interior of the tote bag when the tote bag is in the ed
state. In some embodiments the pocket is made out of an elastic material so that the tote bag is
compressed when in the folded state. When desired, the tote s to carry an alternate pair
of shoes with sufficient volume for additional items. In some embodiments this pocket is
made out of a two-way stretch material and is e of self—folding into a shape that
minimizes volume (e.g, an approximately spherical shape).
Referring to Figure 12, a pouch made of stretch nylon, polyester or similar material
adds functionality by safely and cleanly storing the foldable footwear and related items. The
pouch compresses the footwear in their folded configuration for minimal size when stored or
transported. A rounded edge on the bottom of the pouch further decreases volume and
increases compression. The pouch is sized just smaller than the footwear to minimize bulk. A
drawstring around the opening of the pouch further aids ssion, and seals dirty shoes
from purse or pocket contents. A pocket located on one side of the pouch allows for
compressed storage of the tote bag and/or other items.
The disclosed foldable shoe design allows for footwear to be worn in a normal manner,
consistent with conventional rigid sole products, and suitable for various surfaces, weather,
fashions, etc. When storage or portability is desired, the shoes are folded manually at
imately their midpoint, thus reducing their length in half. In their folded configuration,
the shoes can be stacked and placed in the compacting pouch for maximum compression and
portability. Once stowed in the pouch, the pair requires y the space of a wallet, and may
be carried in a purse or pocket.
Now that an overview of the inventive shoe has been disclosed, specific features and
various embodiments of the disclosed shoes will now be described. Referring to Figure 7,
illustrated is a shoe in accordance with the present disclosure. The shoe comprises an upper 2.
The upper 2 forms an or portion 62 for receiving a foot of a woman. The interior portion
includes a toe cavity 4 and a heel cavity 6.
Referring to Figure 9, the shoe further comprises a midsole 8. The midsole 8 has (i) a
toe end 10, (ii) a heel end 12, (iii) an inner side 14 and (iv) an outer side 16. A perimeter of
the midsole 8 is stitched to the upper 2. The stitching of the e 8 to the upper 2 thereby
forms a bottom to the interior portion 62 that is bounded by a first seam 22. A heel outsole
patch 24 is stitched onto a heel portion of a first face of the midsole 8. A toe outsole patch 26
is stitched onto a toe portion of the first face of the midsole 8.
In typical embodiments, the heel outsole patch 24 and the toe outsole patch 26 are
stitched onto the midsole before the midsole 8 has been ed to the upper 2.
Referring to Figure 6, there is a spacing 32 n (i) the heel e patch 24
stitched onto the heel portion of the first face of the midsole 8 and (ii) the toe outsole patch 26
stitched onto the toe portion of the first face of the midsole 8. The spacing 32 extends from
the inner side 14 to the outer side 16 of the midsole 8 and occupies a position intermediate the
toe end 10 and the heel end 12 of the e 8 thereby permitting the entire shoe to fold about
an axis 34 in the spacing 32 running between the inner side 14 and the outer side 16. In some
embodiments, the spacing is between 4/8 of an inch and 6/8 of an inch. In some embodiments,
the spacing is about 5/8 of an inch. In taking these measurements, an “average” distance
between the heel outsole patch 24 and the toe outsole patch 26 across the region bounded by
the inner side 14 and the outer side 16 may be taken. For example, at several different points
in the region bounded by the inner side 14 to the outer side 16, the distance between the edge
of the heel outsole patch 24 and the edge of the toe outsole patch 26 may be ed and
these measurements may be averaged together to determine the distance between the heel
outsole patch 24 and the toe outsole patch 26. In some embodiments the spacing is simply a
break between the heel outsole patch 24 and the toe outsole patch 26.
Continuing to refer to Figure 6, the insole 30 is affixed by glue to the bottom of the
or portion.
The shoe is configured to fold between (i) an extended state wherein the heel e
patch 24 and the toe e patch 26 are coplanar or approximately coplanar (Figures 1
through 9) and (ii) a folded state in which the shoe is bent about the axis 34 such that a portion
of the upper 2 sing the toe cavity 4 is tucked into the heel cavity 6 (Figure 11).
In some embodiments, the insole 30 is not stitched to the upper 2. Thus, in such
embodiments, the first seam 22, illustrated in Figure 9, only joins the upper 2 and the midsole
8, not the insole 30. Referring to Figure 9, this affords a substantial advantage because it
allows a perimeter (edge) of the heel and toe outsole patches 24, 26 to be brought closer to the
first seam 22 than in instances where the first seam binds the upper 2, midsole 8 and the insole
together, and allows for thicker heel and toe e patches, and more substantial (thicker,
and more rigid) cushioning in the insole. This distance is illustrated as distance 104 in Figure
9A. Accordingly, in embodiments where the first seam 22 only joins the upper 2 and the
midsole 8, the edge of the back comer 64 of the toe outsole patch 26 is within 1/4 of an inch of
a portion of the first seam 22. This proximity to the seam 22, along with the thickness of the
outsole patches, ageously serves to protect the first seam 22 as well as the region of the
midsole 8 in the spacing 32 from wear and tear. In some embodiments, an edge of front
comer 66 of the toe outsole patch 26 is within 1/4 of an inch of a portion of the first seam 22.
In typical embodiments, the distance 104 between the edge of the toe outsole pouch 26
and the first seam 22 is m. In some embodiments in which this distance 104 is m,
(i) the edge of the back comer 64 and (ii) the edge of the front comer 66 of the toe outsole
patch 26 are tively within 4/8 of an inch, 3/8 of an inch, or 2/8 of an inch of a
corresponding portion of the first seam 22.
In some embodiments, an edge ofthe back comer 68 of the heel e patch 24 is
within 3/16 of an inch of a portion of the first seam 22. In some embodiments, an edge of the
front comer 70 of the heel outsole patch 24 is between 2/4 of an inch and 3/4 of an inch of a
portion of the first seam 22. In some embodiments, the distance 104 between the edge of the
heel outsole pouch 24 and the first seam 22 is uniform. In some embodiments in which this
distance 104 is uniform, (i) the edge of the back corner 68 and (ii) the edge of the front comer
70 of the heel e patch 24 are respectively within 4/8 of an inch, 3/8 of an inch, or 2/8 of
an inch of a corresponding portion of the first seam 22. In some ments, the distance
104 between the edge of the heel outsole pouch 24 and the first seam 22 is not uniform. In
some embodiments in which this distance 104 is not uniform, the edge of the back comer 68
of the heel outsole patch 26 is within 3/8 of an inch, or 2/8 of an inch of a corresponding
portion of the first seam 22.
Such proximate distances 104, combined with the thickness of the rubber and rigidity
of the cushioning enabled by the described method of ly, facilitate the protection of the
midsole 8 and the upper 2, thus ensuring the durability of the shoe while at the same time
allowing for a foldable design that remains flexible and comfortable.
ing to Figure 9A, a unique and improved feature of the t shoes is the value
of a durability coefficient. As used herein, the term “durability coefficient” is defined as the
thickness 106 of an outsole patch divided by the distance 104 between the edge of the outsole
patch and the first seam 22. In some embodiments, the distance 104 is 4 mm and the thickness
106 is also 4 mm and thus the durability coefficient is unity. In some embodiments, the
distance 104 is 4 mm and the ess 106 is 5 mm and thus the durability coefficient is 1.25.
In some embodiments, the durability coefficient is between 0.8 and 1.5. In some
ments, the durability coefficient is between 0.9 and 1.4. In some embodiments, the
durability coefficient is between 1.0 and 1.3.
In some embodiments, advantageously, the heel outsole patch 24 and the toe outsole
patch 26 are each at least 3/32 of an inch thick. In some ments, ageously, the
heel outsole patch 24 and the toe outsole patch 26 are each at least 4/32 of an inch thick. In
some embodiments, the heel outsole patch 24 and the toe outsole patch 26 are each at least
/32 of an inch thick. In some embodiments, the heel outsole patch 24 and the toe outsole
patch 26 are each at least 6/32 of an inch thick. In some ments, the heel outsole patch
24 and the toe outsole patch 26 are each at least 7/32 of an inch thick. In some embodiments,
the heel outsole patch 24 and the toe outsole patch 26 are each at least 8/32 of an inch thick.
Such ess increases the spring constant of the soles, leading to greater support for the foot
and increased lity of the shoe. Referring to Figure 1, because of the thickness of the
outsole s, and their proximity to the edge, it is possible to view a side of the outsole
patch at least at a 45 degree angle 100 from the horizontal 102 when the shoe is worn on a
woman’s foot when the woman is standing upright with respect to the horizontal. In some
embodiments, it is possible to view a side of the outsole patch at least at a 50 degree angle, at
least a 55 degree angle, or at least a 60 degree angle 100 from the horizontal 102 when the
shoe is worn on a woman’s foot when the woman is standing upright with respect to the
ntal. This visibility of the outsole patches is described herein solely to set forth a
description of the dimensions and shapes of the disclosed shoes.
In some embodiments, the heel outsole patch 24 and the toe outsole patch 26 are each
made out of an elastomer. Exemplary elastomers that may be used include but are not limited
to, for example, natural rubber, vulcanized natural rubber, a butadiene-styrene mer such
as GR-S, neoprene, nitrile rubbers, butyl, polysulfide rubbers, ethylene—propylene rubbers,
polyurethane rubbers, and silicone rubbers as described in Marks ’ Standard Handbookfor
Mechanical Engineers, 1987, Avallone and Baumeister, eds., McGraw-Hill, New York, pp. 6—
161 through l-l63, which is hereby incorporated herein by reference. In some embodiments
the e 8 is made out of leather.
Referring to s 6, 6A, and 6B, in some embodiments the shoe is Characterized by
a midsole 8. A heel outsole patch 24 and a toe outsole patch 26 are sewn onto a first face of
the midsole 8. The midsole 8 comprises a second face having a heel portion 68 and a toe
portion 70. In some ments, a cushion insert 46 is glued to the heel portion 68 of a
second face of the midsole 8. The insert 46 absorbs impact to the foot when walking on hard
surfaces. The insert 46 molds to the foot over time. A foam inlay 44 is glued to (i) the
cushion insert 46 and (ii) the toe portion 70 of the second face of the midsole 8. Next an
insole 30 is affixed by glue to the foam inlay 44. The cushion insert 46 is characterized by a
first end 76 and a second end 78. The first end 76 of the cushion insert 46 is glued to a first
part 72 of the heel portion 68 and the second end 78 of the cushion insert 46 is glued to a
second part 74 of the heel portion 68. The first part 72 of the heel portion 68 is closer to the
toe portion 70 of the second face of the midsole 8 than the second part 74 of the heel portion
68. In some ments, the first end 76 of the cushion insert 46 has a thickness that is less
than the thickness of the second end 78 of the cushion insert 46. In some embodiments, the
cushion insert 46 has a thickness that increases along the cushion insert 46 as a function of a
distance away from the toe portion 70 of the second face of the midsole 8 so that a portion of
the cushion insert that is closest to the toe portion 70 of the midsole is thinner than a portion of
the cushion insert 46 that is farthest away from the toe portion 70 of the midsole 8. In some
ments, the maximum thickness of the cushion insert 46 is 3 millimeters or more, 4
millimeters or more, 5 eters or more, 6 millimeters or more, 7 millimeters or more, or 8
millimeters or more. This advantageously serves to improve the support provided by the shoe,
particularly at the heel, provides desired lift, and increases rigidity and thereby durability.
In on to providing a graduated thickness to improve foot support, the cushion
insert 46 is made out of a rigid material such as a rigid ethylene vinyl acetate or similar
n material. In some ments, the cushion insert 46 has a Shore A ss of
between 45 and 70 or between 60 and 70. In some embodiments, the cushion insert 46 has a
density of between 0.30 g/cm3 and 0.5 g/cm3, between 0.40 g/cm3 and 0.5 g/cm3, between 0.45
g/cm3 and 0.5 g/cm3, or between 0.50 g/cm3 and 0.70 g/cm3.
The thickness of the heel e patch 24 and the toe outsole patch 26 together with
the materials used to make these patches, the proximity of these s to the seam 22 and the
ability to add the cushion insert, contributes to a greatly ed spring constant relative to
known foldable shoes. In some embodiments, the overall spring constant of the shoe taken
lengthwise in the heel portion 68 of the shoe , in the region of the heel e patch 24) is
between 0.40 kilogram—force / inch and 0.70 kilogram-force / inch. In some embodiments, the
overall spring constant of the shoe taken lengthwise in the heel portion 68 of the shoe is
between 0.45 kilogram-force / inch and 0.65 kilogram-force / inch, or between 0.55 kilogram-
force / inch and 0.65 kilogram-force / inch. In some embodiments, the overall spring constant
of the shoe taken lengthwise in the heel portion 68 of the shoe is about 0.6 kilogram-force/
inch. Referring to Figure 6, to arrive at the spring constant measurement, the portions 68 and
70 are measured separately. For each , with the shoe held in an upright position one end
(z'.e., one end of n 68 or 70 going the long way and with shoe facing up as it would be
worn) is anchored and then the other end of the portion 68 or 70 of the shoe being measured is
forced down a set distance (e.g, 1 inch) and the force exerted by the pushed down end is then
measured.
In some embodiments, the overall spring constant of the shoe taken lengthwise in the
toe portion 70 of the shoe (i.e., in the region of the toe outsole patch 26) is between 0.40
kilogram-force / inch and 0.70 am-force / inch. In some embodiments, the overall spring
constant of the shoe taken lengthwise in the toe portion 70 of the shoe is between 0.45
kilogram-force / inch and 0.65 am-force / inch or between 0.55 kilogram-force / inch
and 0.65 am-force / inch. In some embodiments, the overall spring constant of the shoe
taken lengthwise in the toe portion 68 of the shoe is about 0.6 kilogram-force / inch.
Another advantageous feature of the shoes in ance with some embodiments of
the present disclosure are deep grooves in the heel e patch 24 and the toe outsole patch
26 that facilitate the stitching of the patches to the midsole 8 while at the same time protecting
the stitching. The deep grooves 48 are enabled by the advantageous design in which thick
outsole patches are employed that, at the same time, are proximate to the first seam 22 which
attaches the upper 2 to the midsole 8. The deep grooves 48 protect the stitching that attaches
the outsole s to the midsole 9 from contact with the , which would cause the
stitching to wear and thereby cause the outsole patches to become detached. These
advantageous features are d. By only stitching the upper 2 to the midsole 8 to form the
first seam, rather than further stitching insole 30 to the midsole 8, it is possible to both
minimize distance 104 and increase thickness of the outsole patches 24/26 while still being
able to stitch the midsole 8 to the upper 2 using conventional processes such as a sewing
machine. Because distance 104 is minimized, it is possible to make the outsole patches 24/26
r (i.e., increase distance 106) without destabilizing foot support. Because the outsole
patches 24/26 are thicker, it is possible to make the first groove 48 deeper thereby better
2011/060662
protecting the stitching within the groove. Moreover, because the outsole patches are thicker,
the shoe is firm and allows for use for longer s of time and a greater spectrum of terrain
(e.g., on asphalt, te, dirt roads, etc.) Referring to Figure 9, one such advantageous
embodiment has a first groove 48 having a depth of at least 3/64 of an inch that is formed
proximate to a perimeter of the heel outsole patch 24. The heel outsole patch 24 is stitched
onto the heel portion of the first face of the midsole 8 with a first thread that occupies the first
groove 48. Further, a second groove 50 having a depth of at least 3/64 of an inch is formed
proximate to a perimeter of the toe outsole patch 26. The toe outsole patch 26 is stitched onto
the toe portion of the first face of the midsole 8 with a second thread that occupies the second
groove 50. In some embodiments, the first groove 48 is about 3/32 of an inch. In some
embodiments, the second groove 50 is about 3/32 of an inch.
Referring to Figure 5, the upper 2 is formed as a single piece having a first end and a
second end, where the first end and the second end are united by a second seam 52 at the heel
cavity. In some embodiments upper 2 is formed of two or more pieces.
Referring to s 3 and 9, in typical embodiments, the upper 2 is formed as a single
piece having (i) a first end (80), (ii) a second end (82), (iii) a first edge (84) (visible in Figure
9), and (iv) a second edge (86). In some embodiments, upper 2 is formed of two or more
pieces sewn er. Referring to Figure 3, in typical embodiments, upper 2 is a single piece
having ends 110A and 1 10B. Of course, upper 2 may be formed by any number of pieces
sewn together into a single piece having ends 110A and 110B. Regardless of whether upper
originates as one or multiple pieces, ends 110A (first end) and 110B (second end) are united
by a second seam 52 at the heel cavity 6 to complete the upper 2. Referring to Figure 9, the
first edge 84 of the upper 2 is stitched to the perimeter of the midsole 8 thereby forming the
second seam 22 and the bottom to the or portion of the shoe. ing back to Figure 3,
a first portion of the second edge 86 is characterized by an elastic restriction 60, where the
portion of the second edge does not extend to the heel cavity 6. In some embodiments, the
second portion of the second edge 86 is characterized by an Achilles cushion 56 that provides
an upper boundary to the heel cavity 6. Further, referring to Figure 5, in some embodiments, a
half-moon piece 58 covers a lower portion of the second seam 52 whereas a strip portion 54
covers an upper portion of the second seam 52.
Referring to Figure 11, in some embodiments, the shoe is in a folded state. In this
folded state, the shoes can be tucked into a stretch nylon or similar material compacting pouch
(Figure 12), having a ring. This provides for the advantageous transport of the shoes in
a clean and compact state, while ssed into a minimal size. In some embodiments, the
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pouch includes a pocket for holding a tote bag, where the tote bag is configured to
accommodate a pair ofwomen’s shoes, or other items and personal effects. This allows for
the possibility of carrying the shoes of the present disclosure in the pouch, while on the road,
and switching to wearing the shoes of the present sure by storing unwanted previously
worn shoes in the tote bag after it has been d from the pocket of the pouch, and
expanded from its collapsed form.
Advantageously, the shoes of the present disclosure tuck into a folded state so that they
may be stored in a compact box having a lid. Such a compact box is rated in Figure 10.
In some embodiments, the edge of the e patches are beveled in two ways. First,
outside edge of the outsole patch is beveled at steep incline for durability and tic
reasons. By preserving a steep bevel on the outside edge of the outsole patches, a r
space is maintained between the walking surface and soft elements of the footwear, thereby
increasing durability. Second, in some embodiments the interior edge of one or more outsole
patches is beveled. By beveling the outsole patch in this manner, pressure between the edge of
the outsole patch and the softer midsole is reduced. This beveling blunts and softens the edge
of the outsole patch that is not affixed to the midsole. By ing this edge, durability and
longevity of the footwear is improved.
As discussed above, prior art split sole ar suffer from certain limitations. In
some embodiments, the shortcomings of the prior art are overcome by providing shoes that
achieve a maximum outsole ratio (OR), where OR is defined as:
OR_D><T><W_
where,
D = average depth of second groove 50,
T = average thickness of toe outsole patch 26,
W = maximum width oftoe outsole patch 26, and
M = width of midsole 8 at point ofmaximum width oftoe outsole patch 26,
where W is less than M, and D, T, W and M are all given in the same unit of
ement (6.g.
, millimeters).
Accordingly, in some embodiments, the shoes of the present disclosure have an outsole ratio
OR. When this ratio is maximized, the toe outsole patch 26 is thick, the second groove 50 in
which the toe outsole patch 26 ing is made is deep, and the toe outsole patch 26 is close
to the edge of the footwear. In some embodiments, an acceptable outsole ratio requires a toe
outsole patch 26 that is as narrow as possible while still able to odate a wide range of
foot widths. The more narrow the toe outsole patch 26, the more compact and le the
footwear, and the better it will accommodate a narrow foot. A thicker toe outsole patch 26 is
important to foot safety and comfort when walking on uneven surfaces.
Further, as the width of the toe outsole patch 26 is ed, the depth of the second
groove 50 for its stitching becomes more important because that seam area will receive more
contact with the g surface. Thus, a deep groove 50 is necessary to protect the seam
stitching. Also increasing in importance as the width of the toe outsole patch 26 is narrowed is
the coverage of midsole 8 by the toe outsole patch 26 and its proximity to the edge of the
upper 2. The benefits of a toe outsole patch 26 that is closer to the edge of the footwear have
been presented above. Given the present disclosure, it will be appreciated that these same
principles apply to the heel outsole patch 24 and first groove 48.
Table 1 below illustrates red values for average depth of second groove 50 (D),
average thickness of toe e patch 26 (T), maximum width of toe outsole patch 26 (W),
and width of e 8 at point ofmaximum width of toe outsole patch 26 (M) in accordance
with an embodiment of the present disclosure.
Table I, referred measurements for shoes in accordance with one as oect of the disclosure.
Women’s Shoe Size
(American) 5 7 8 1 0 1 1 l 2
Second groove 50 depth
(D) inmm 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5
Toe outsole patch 26
thickness (T) in mm 4 4 4 4 4 4 4 4
Maximum width of toe
outsole patch 26 (W) in
mm 72 75 78 81 84
Width of midsole 8 at
point of measurement of
toe outsole patch 26 (M)
in mm 74 77 80 83 89 92 94
DXTXW
M 8.92 8.96 9.00 9.04 9.07 9.10 9.13 9.15
In some embodiments, the shoes of the present disclosure has an outsole ratio of 7.0 or
greater. In some embodiments, the shoes of the present disclosure has an outsole ratio of 7.2
or greater. In some embodiments, the shoes of the present disclosure has an outsole ratio of
7.4 or greater. In some embodiments, the shoes of the present disclosure has an outsole ratio
of 7.6 or greater. In some embodiments, the shoes of the present disclosure has an outsole
ratio of 7.8 or greater. In some embodiments, the shoes of the present disclosure has an
outsole ratio of 8.0 or greater. In some embodiments, the shoes of the present disclosure has
an outsole ratio of 8.2 or greater. In some ments, the shoes of the present disclosure
has an outsole ratio of 8.4 or greater. In some embodiments, the shoes of the present
disclosure has an outsole ratio of 8.6 or greater. By ing an outsole ratio of this
magnitude, several ts arise which increase the viability of split sole footwear.
Tables 2 and 3 below illustrate preferred values for average depth of second groove
50 (D), average thickness of toe e patch 26 (T), maximum width of toe e patch 26
(W), and width of midsole 8 at point of maximum width of toe outsole patch 26 (M) in
accordance with embodiments of the present disclosure.
Table 2, red ements for shoes in accordance with one aspect of the disclosure.
Women’s Shoe Size
can) 5 6 7 8 9 10 11 12
Second groove 50 depth (D)
in mm 2.5±.5 2.5±.5 2.5±.5 2.5±.5 2.5±.5 2.5±.5 2.5±.5 2.5±.5
Toe outsole patch 26
thickness (T) in mm 4±.5 4±.5 4±.5 4±.5 4±.5 4±.5 4±.5 4±.5
Maximum width of toe 8
outsole patch 26 (W) in mm 66±2 69±2 72±2 75±2 78±2 81±2 84±2 86±2
Width of midsole 8 at point
of measurement of toe 7 7 8 8 8 8 9 9
outsole patch 26 (M) in mm 74±2 77±2 80±2 83±2 86±2 89±2 92±2 94±2
Table 3, preferred measurements for shoes in accordance with one aspect of the disclosure.
Women’s Shoe Size
(American) 5 6 7 8 9 10 11 12
Second groove 50 depth (D)
in mm 2.5±1 2.5±1 2.5±1 2.5±1 2.5±1 2.5±1 2.5±1 2.5±1
Toe outsole patch 26
thickness (T) in mm 4±1 4±1 4±1 4±1 4±1 4±1 4±1 4±1
Maximum width of toe
outsole patch 26 (W) in mm 66±4 69±4 72±4 75±4 78±4 81±4 84±4 86±4
Width of midsole 8 at point
of measurement of toe
outsole patch 26 (M) in mm 74±4 77±4 80±4 83±4 86±4 89±4 92±4 94±4
In some embodiments, a shoe is ed that achieves a maximum outsole ratio (OR),
where OR is defined as:
D’ x T’Ix W’
OR’ =
where,
D’ = is the e depth of second groove 50 and is a value of between 2.0
mm and 3.0 mm,
T’ = is the e thickness of the toe outsole patch 26 and is a value of at
least 3.0 mm,
W’ = maximum width of toe outsole patch 26, and is a value of between 60 mm
and 89 mm, and
M’ = width of midsole 8 at point ofmaximum width of toe outsole patch 26,
and is a value greater than W’ that is between 70 mm and 93 mm, and n
OR’ is a value between 7.0 and 8.6.
In some embodiments, T’ has a value of at least 4.0 mm, at least 5.0 mm, at least 6.0 mm, at
least 7.0 mm, at least 8.0 mm, or at least 9.0 mm.
A first benefit of the shoes satisfying the OR metric is improved comfort. Thicker
e patches allows for more cushion between foot and g surface and minimizes the
impact of hard objects. Wide outsole patches that are closer to the edge of the shoe covers
more of bottom of foot, preventing the foot from the uncomfortable feeling putting pressure on
the edge of the outsole or worse, hanging over the edge of the rubber.
A second benefit is improved protection of the foot. Thicker outsoles provide more of
a barrier and thus more protection to the foot against hard or sharp objects. Further, wider
outsoles provide more protection and coverage of the foot.
A third benefit is enhanced durability. Outsoles close to the edge of the shoe protects
the seam stitching, outsole (24, 26), midsole (8), and other delicate elements of the shoe.
Thicker outsoles (24, 26) provide more outsole to wear down before te parts of the shoe
(e.g. , e 8) wear out from contact with ground. A deeper groove (e.g., first groove 48
and second groove 50) ts outsole stitching better so it doesn’t wear out as quickly.
A forth benefit is that it enables a more attractive style: the narrower shoe flexes to
adapt to wider feet when necessary. This is accomplished by a deep groove (e.g., first groove
48 and second groove 50) that protects stitching from increased contact that the groove, and
thus the stitching therein, has with ground on narrower shoe. This is further accomplished by
a thick outsole patch (e.g. heel outsole patch 24 and toe outsole patch 26) that is close to the
edge that becomes increasingly important on narrow shoes as some feet are wider than the
outsole. Here, the outsole thickness ts wider feet from pushing seam / midsole 8/ upper
2 down on to ground
A fifth benefit is that the shoe is more portable and compact because the non-foldable
heel outsole patch 24 and toe outsole patch area is zed.
EXEMPLARY EMBODIMENTS
The following are nonlimiting exemplary embodiments ofthe present disclosure.
Embodiment A. A shoe comprising:
an upper, the upper forming an interior portion for receiving a foot of a person, the
interior portion including a toe cavity and a heel cavity;
a midsole, the midsole having (i) a toe end, (ii) a heel end, (iii) an inner side, and (iv)
an outer side, wherein a perimeter of the midsole is stitched to the upper thereby forming a
bottom to the or portion that is bounded by a first seam;
a heel outsole patch ed onto a heel portion of a first face of the midsole;
a toe outsole patch stitched onto a toe portion of the first face of the midsole;
an insole that is affixed by glue to the bottom of the interior portion;
wherein there is a spacing between (i) the heel outsole patch ed onto the heel
portion of the first face of the midsole and (ii) the toe outsole patch stitched onto the toe
portion of the first face of the e, the spacing extending from the inner side to the outer
side and occupying a position intermediate the toe end and the heel end thereby permitting the
entire shoe to fold about an axis in the spacing running between the inner side and the outer
side;
wherein the shoe is red to fold between (i) an extended state wherein the heel
outsole patch and the toe outsole patch are coplanar or approximately coplanar and (ii) a
folded state in which the shoe is bent about the axis such that a portion of the upper
comprising the toe cavity is tucked into the heel cavity, and wherein
(i) the insole is not stitched to the upper or midsole, and
(ii) the heel outsole patch and the toe outsole patch are each made out of an elastomer.
Embodiment B. A shoe comprising:
an upper, the upper forming an interior portion for receiving a foot of a , the
or portion ing a toe cavity and a heel cavity;
a midsole, the midsole having (i) a toe end, (ii) a heel end, (iii) an inner side, and (iV)
an outer side, wherein a perimeter of the midsole is stitched to the upper thereby forming a
bottom to the interior n that is bounded by a first seam;
a heel outsole patch stitched onto a heel portion of a first face of the midsole;
a toe outsole patch stitched onto a toe portion of the first face of the midsole;
an insole that is affixed by glue to the bottom of the interior portion;
wherein there is a spacing between (i) the heel outsole patch stitched onto the heel
portion of the first face of the midsole and (ii) the toe outsole patch stitched onto the toe
portion of the first face of the midsole, the g extending from the inner side to the outer
side and occupying a position intermediate the toe end and the heel end thereby permitting the
entire shoe to fold about an axis in the spacing g between the inner side and the outer
side;
wherein the shoe is configured to fold between (i) an extended state wherein the heel
outsole patch and the toe outsole patch are coplanar or approximately coplanar and (ii) a
folded state in which the shoe is bent about the axis such that a portion of the upper
comprising the toe cavity is tucked into the heel cavity, and wherein
(i) the insole is not stitched to the upper, and
(ii) a region of the shoe defined by the heel outsole patch and sing a
corresponding n of the midsole and the insole has a spring constant ofbetween 0.40
am-force / inch and 0.70 kilogram-force / inch.
Embodiment C. A shoe sing:
an upper, the upper forming an interior portion for receiving a foot of a person, the
interior portion including a toe cavity and a heel cavity;
a midsole, the midsole having (i) a toe end, (ii) a heel end, (iii) an inner side, and (iv)
an outer side, wherein a perimeter of the midsole is stitched to the upper thereby forming a
bottom to the interior portion that is bounded by a first seam;
a heel outsole patch ed onto a heel n of a first face of the midsole;
a toe outsole patch stitched onto a toe portion of the first face of the midsole;
an insole that is affixed by glue to the bottom of the interior portion;
wherein there is a spacing between (i) the heel e patch stitched onto the heel
portion of the first face of the midsole and (ii) the toe outsole patch stitched onto the toe
portion of the first face of the midsole, the spacing extending from the inner side to the outer
side and occupying a on intermediate the toe end and the heel end thereby permitting the
entire shoe to fold about an axis in the spacing running between the inner side and the outer
side;
wherein the shoe is configured to fold between (i) an extended state wherein the heel
outsole patch and the toe outsole patch are coplanar or approximately coplanar and (ii) a
folded state in which the shoe is bent about the axis such that a portion of the upper
comprising the toe cavity is tucked into the heel cavity, and wherein
(i) the insole is not stitched to the upper, and
(ii) a back comer of the toe outsole patch is within 1/4 of an inch of a portion of the
first seam.
Embodiment D. A shoe comprising:
an upper, the upper forming an interior portion for receiving a foot of a person, the
interior n including a toe cavity and a heel ;
a midsole, the midsole having (i) a toe end, (ii) a heel end, (iii) an inner side, and (iv)
an outer side, wherein a perimeter of the midsole is stitched to the upper thereby forming a
bottom to the interior portion that is bounded by a first seam;
a heel outsole patch stitched onto a heel portion of a first face of the e;
a toe outsole patch stitched onto a toe portion of the first face of the midsole;
an insole that is affixed by glue to the bottom of the interior n;
wherein there is a spacing between (i) the heel outsole patch stitched onto the heel
portion of the first face of the e and (ii) the toe outsole patch ed onto the toe
portion of the first face of the midsole, the g extending from the inner side to the outer
side and occupying a position intermediate the toe end and the heel end thereby permitting the
entire shoe to fold about an axis in the spacing running n the inner side and the outer
side;
n the shoe is configured to fold between (i) an extended state wherein the heel
outsole patch and the toe outsole patch are coplanar or approximately coplanar and (ii) a
folded state in which the shoe is bent about the axis such that a portion of the upper
comprising the toe cavity is tucked into the heel cavity, and wherein
(i) the insole is not stitched to the upper,
(ii) a first groove having a depth of at least 3/64 of an inch is formed proximate to a
perimeter of the heel outsole patch and wherein the heel outsole patch is ed onto the heel
portion of the first face of the midsole with a first thread that occupies the first groove; and
(iii) a second groove having a depth of at least 3/64 of an inch is formed proximate to a
perimeter of the toe outsole patch and wherein the toe outsole patch is stitched onto the toe
portion of the first face of the midsole with a second thread that es the second groove.
Embodiment E. A shoe comprising:
an upper, the upper g an interior portion for receiving a foot of a , the
interior portion including a toe cavity and a heel cavity;
a midsole, the midsole having (i) a toe end, (ii) a heel end, (iii) an inner side, and (iv)
an outer side, wherein a ter of the e is ed to the upper thereby forming a
bottom to the interior portion that is bounded by a first seam;
a heel outsole patch stitched onto a heel portion of a first face of the midsole;
a toe outsole patch stitched onto a toe portion of the first face of the e;
an insole that is affixed by glue to the bottom of the interior portion;
wherein there is a spacing between (i) the heel e patch stitched onto the heel
portion of the first face of the midsole and (ii) the toe outsole patch stitched onto the toe
portion of the first face of the midsole, the spacing extending from the inner side to the outer
side and occupying a position intermediate the toe end and the heel end thereby permitting the
entire shoe to fold about an axis in the spacing running between the inner side and the outer
side;
wherein the shoe is configured to fold between (i) an extended state wherein the heel
outsole patch and the toe outsole patch are coplanar or approximately coplanar and (ii) a
folded state in which the shoe is bent about the axis such that a n of the upper
comprising the toe cavity is tucked into the heel cavity, and wherein
(i) a region of the shoe defined by the heel outsole patch and comprising a
corresponding portion of the midsole and the insole has a spring constant ofbetween 0.45
kilogram—force / inch and 0.55 am-force / inch; and
(ii) the toe e patch or the heel outsole patch has a durability coefficient of
between 0.8 and 1.5.
Embodiment F. A method of manufacturing a shoe, the method comprising:
(A) stitching a heel outsole patch onto a heel portion of a first face of a midsole;
(B) stitching a toe outsole patch onto a toe portion of the first face of the midsole;
(C) affixing a cushion insert to the heel portion of a second face of the midsole,
(D) sewing an upper, the upper forming an interior portion for receiving a foot of a
person, the interior portion including a toe cavity and a heel cavity, to the midsole, the midsole
having (i) a toe end, (ii) a heel end, (iii) an inner side, and (iv) an outer side, wherein the
sewing (D) results in a ter of the midsole being stitched to the upper thereby forming a
bottom to the or portion that is bounded by a first seam;
(E) affixing by glue an insole to the bottom of the interior portion;
wherein, the ing (A) and stitching (B) form a spacing between (i) the heel outsole
patch stitched onto the heel portion of the first face of the midsole and (ii) the toe outsole
patch stitched onto the toe portion of the first face of the midsole, the spacing extending from
the inner side to the outer side and occupying a position intermediate the toe end and the heel
end thereby permitting the entire shoe to fold about an axis in the spacing running between the
inner side and the outer side;
wherein the shoe is configured to fold between (i) an extended state wherein the heel
outsole patch and the toe outsole patch are coplanar or approximately coplanar and (ii) a
folded state in which the shoe is bent about the axis such that a n of the upper
sing the toe cavity is tucked into the heel cavity, and wherein
(i) the insole is not stitched to the upper or midsole, and
(ii) the heel outsole patch and the toe outsole patch are each made out of an mer.
Embodiment G. A method of manufacturing a shoe, the method comprising:
(A) stitching a heel e patch onto a heel portion of a first face of a midsole;
(B) stitching a toe outsole patch onto a toe portion of the first face of the midsole;
(C) sewing an upper, the upper forming an interior portion for receiving a foot of a
, the or portion including a toe cavity and a heel cavity, to the midsole, the midsole
having (i) a toe end, (ii) a heel end, (iii) an inner side, and (iv) an outer side, wherein the
sewing (C) results in a perimeter of the midsole being stitched to the upper thereby forming a
bottom to the interior portion that is bounded by a first seam;
(D) affixing by glue an insole to the bottom of the interior portion;
n, the stitching (A) and stitching (B) form a spacing between (i) the heel outsole
patch stitched onto the heel portion of the first face of the midsole and (ii) the toe outsole
patch stitched onto the toe portion of the first face of the midsole, the spacing extending from
the inner side to the outer side and occupying a position intermediate the toe end and the heel
end thereby ting the entire shoe to fold about an axis in the spacing g between the
inner side and the outer side;
wherein the shoe is configured to fold between (i) an extended state wherein the heel
outsole patch and the toe outsole patch are coplanar or approximately coplanar and (ii) a
folded state in which the shoe is bent about the axis such that a portion of the upper
comprising the toe cavity is tucked into the heel cavity, and n
(i) a region of the shoe defined by the heel outsole patch and comprising a
corresponding portion of the midsole and the insole has a spring constant ofbetween 0.45
kilogram—force / inch and 0.55 kilogram-force / inch; and
(ii) the toe outsole patch or the heel outsole patch has a durability coefficient of
between 0.8 and 1.5.
Embodiment H-l. Any one of embodiments A, B, C, D, E, F and G, wherein the midsole is
made out of leather.
Embodiment H-2. Any one of embodiments A, B, C, D, E, F and G, n the bottom of
the interior portion fiirther comprises a foam inlay and wherein the insole is affixed by glue to
the foam inlay.
Embodiment H—3. Any one of embodiments A, B, C, D, E, F and G, wherein the interior
portion further comprises a cushion insert that is glued to the heel portion of a second face of
the midsole.
Embodiment H-4. The embodiment of H—2, wherein the midsole comprises a second face
having a heel portion and a toe portion and wherein
the interior n further ses a n insert that is glued to the heel n
of a second face of the midsole, and
the foam inlay is glued to (i) cushion insert and (ii) the toe portion of the second face
of the midsole.
Embodiment H—5. The embodiment of H—3, n the cushion insert is characterized by a
first end and a second end, wherein
the first end of the cushion insert is glued to a first part of the heel portion and the
second end of the cushion insert is glued to a second part of the heel portion, wherein the first
part of the heel portion is closer to the toe portion of the second face of the midsole than the
second part of the heel portion, and
the first end of the cushion insert has a ess that is less than the second end of the
cushion insert.
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Embodiment H-6. The ment of H-3, wherein the cushion insert has a ess that
increases along the insert as a function of a distance away from the toe portion of the second
face of the e so that a portion of the cushion insert that is closest to the toe n of
the midsole is thinner than a portion of the cushion insert that is farthest away from the toe
portion of the midsole.
Embodiment H—7. The embodiment of H—3, wherein the cushion insert comprises a ethylene
vinyl acetate or polyurethane type material.
Embodiment H-8. The embodiment of H-3, the cushion insert has a Shore A hardness of
between 45 and 70 or between 60 and 70.
Embodiment H-9. The embodiment of H-3, wherein the cushion insert has a density of
between 0.30 g/cm3 and 0.7 g/cm3.
Embodiment H—lO. The ment of H-3, wherein the cushion insert has a density of
between 0.40 g/cm3 and 0.7 g/cm3.
Embodiment H-1 1. Any one of embodiments A, B, C, D, E, F and G, wherein
a first groove having a depth of at least 3/64 of an inch is formed proximate to a
perimeter of the heel outsole patch and wherein the heel outsole patch is stitched onto the heel
portion of the first face of the midsole with a first thread that occupies the first groove; and
a second groove having a depth of at least 3/64 of an inch is formed proximate to a
perimeter of the toe outsole patch and n the toe outsole patch is stitched onto the toe
portion of the first face of the midsole with a second thread that occupies the second groove.
Embodiment H—lZ. Any one of embodiments A, B, C, D, E, F and G, wherein the upper is
formed as a single piece having a first end and a second end, wherein the first end and the
second end are united by a second seam at the heel cavity.
ment H-13. Any one of embodiments A, B, C, D, E, F and G, wherein
the upper is formed as a single piece having (i) a first end, (ii) a second end, (iii) a first
edge, and (iv) a second edge,
the first end and the second end are united by a second seam at the heel cavity,
the first edge is stitched to the perimeter of the midsole thereby forming the bottom to
the interior portion,
a first portion of the second edge is characterized by an elastic restriction, wherein the
portion of the second edge does not extend to the heel cavity.
Embodiment H—l4. Any one of embodiments A, B, C, D, E, F and G, wherein a second
portion of the second edge is characterized by an Achilles n that provides an upper
boundary to the heel cavity.
Embodiment H-lS. Any one of embodiments A, B, C, D, E, F and G, wherein
the upper is formed as a single piece having a first end and a second end,
the first end and the second end are united by a second seam at the heel cavity, and
a half moon piece covers a lower portion of the second seam.
Embodiment H—l6. Any one of embodiments A, B, C, D, E, F and G, wherein the shoe is in a
folded state and is tucked into a pouch having a ring.
Embodiment H—l7. The embodiment of H—l6, wherein the pouch includes a pocket for
holding a tote bag, n the tote bag is configured to accommodate a pair of shoes.
Embodiment H-18. Any one of embodiments A, B, C, D, E, F and G, wherein the shoe is in a
folded state and is tucked into a compact box having a lid.
Embodiment H—l9. Any one of embodiments A, B, C, D, E, F and G, wherein a back corner
of the toe outsole patch is within 1/4 of an inch of a n of the first seam.
ment H—20. Any one of embodiments A, B, C, D, E, F and G, n a back comer
of the toe outsole patch is within 3/16 of an inch of a portion of the first seam.
Embodiment H-2l. Any one of embodiments A, B, C, D, E, F and G, wherein a front comer
of the toe outsole patch is within l/4 of an inch of a portion of the first seam.
Embodiment H-22. Any one of embodiments A, B, C, D, E, F and G, wherein a back corner
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of the heel outsole patch is within 3/16 of an inch of a portion of the first seam.
Embodiment H-23. Any one of ments A, B, C, D, E, F and G, wherein a back comer
of the heel outsole patch is within 1/4 of an inch of a portion of the first seam.
Embodiment H-24. Any one of embodiments A, B, C, D, E, F and G, wherein the toe outsole
patch or the heel outsole patch has a durability coefficient of between 0.8 and 1.5.
Embodiment H-25. Any one of embodiments A, B, C, D, E, F and G, wherein the toe outsole
patch or the heel outsole patch has a lity coefficient of between 1.0 and 1.3.
Embodiment H-26. Any one of embodiments A, B, C, D, E, F and G, wherein the heel outsole
patch and the toe e patch are each at least 3/32 of an inch thick.
Embodiment H-27. Any one of embodiments A, B, C, D, E, F and G, wherein the heel outsole
patch and the toe outsole patch are each about 5/32 of an inch thick.
Embodiment H—28. Any one of embodiments A, B, C, D, E, F and G, wherein the g is
between 4/8 of an inch and 6/8 of an inch.
Embodiment H-29. Any one of embodiments A, B, C, D, E, F and G, wherein the spacing is
about 5/8 of an inch.
ment H-30. Any one of embodiments A, B, C, D, E, F and G, wherein a side ofthe
heel e patch is Visible at least at a 45 degree angle from the horizontal when the shoe is
worn on a person’s foot who is standing on the horizontal.
Embodiment H—3 1. Any one of embodiments A, B, C, D, E, F and G, wherein a side of the toe
outsole patch is Visible at least at a 45 degree angle from the horizontal when the shoe is worn
on a person’s foot who is standing on the horizontal.
Embodiment H-32. Any one of embodiments A, B, C, D, E, F and G, wherein a region ofthe
shoe defined by the heel outsole patch and comprising a corresponding portion of the midsole
and the insole has a spring constant of between 0.40 kilogram-force / inch and 0.70 kilogram-
force / inch.
ment H-33. Any one of embodiments A, B, C, D, E, F and G, wherein a region of the
shoe defined by the heel outsole patch and comprising a corresponding n of the midsole
and the insole has a spring constant of between 0.45 kilogram—force / inch and 0.55 kilogram-
force / inch.
Embodiment H—34. Any one of embodiments A, B, C, D, E, F and G, wherein a region ofthe
shoe defined by the toe outsole patch and comprising a corresponding portion of the midsole
and the insole has a spring constant of between 0.40 am-force / inch and 0.70 kilogram-
force / inch.
Embodiment H-35. Any one of embodiments A, B, C, D, E, F and G, wherein a region of the
shoe defined by the toe outsole patch and comprising a corresponding portion of the midsole
and the insole has a spring constant of between 0.45 kilogram-force / inch and 0.55 kilogram-
force / inch.
Embodiment H—36. Any one of ments A, B, C, D, E, F and G, wherein the shoe is a
shoe for women.
Embodiment H-37. Any one of embodiments A, B, C, D, E, F and G, wherein the shoe is a
shoe for men.
Embodiment H-38. Any one of embodiments A, B, C, D, E, F and G, wherein the shoe is a
shoe for men, women, or children.
REFERENCES CITED AND ALTERNATIVE EMBODIMENTS
All references cited herein are orated herein by reference in their entirety and for
all purposes to the same extent as if each individual publication or patent or patent ation
was specifically and individually indicated to be incorporated by reference in its entirety for
all purposes.
Many modifications and variations of this invention can be made without ing
from its spirit and scope, as will be apparent to those skilled in the art. The specific
embodiments described herein are offered by way of example only. The embodiments were
chosen and described in order to best explain the principles of the invention and its practical
applications, to thereby enable others skilled in the art to best utilize the ion and various
embodiments with various modifications as are suited to the particular use contemplated.
This disclosure extends to various footwear styles (in addition to the basic ballet
flat/slipper depicted in the diagrams). For example: sandals, flip-flops, active and athletic
shoes can be made with a similar construction for flexible compression and compact storage
and are fully encompassed within the scope of the present invention. er, while
ments have been disclosed that are designed for woman, it will be appreciated that such
shoes can be designed for men, children, or any combination ofwoman, men, and children.
All such alternative designs are fully within the scope of the present sure.
The core shoe design and compacting pouch bed offer cant potential for
cial differentiation Via ornamentation, materials, and colors, increasing their
commercial appeal. Alternative construction methods may include gluing of the outsoles to
the midsole without any stitching. The invention is to be limited only by the terms of the
appended claims, along with the full scope of equivalents to which such claims are entitled.