Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02713623 2010-09-03
Articles of Footwear
TECHNICAL FIELD
[0001] This disclosure relates to articles of footwear having forefoot
cushioning.
BACKGROUND
[0002] Articles of footwear, such as shoes, are generally worn while
exercising to
protect and provide stability of a user's feet. In general, shoes include an
upper portion
and a sole. When the upper portion is secured to the sole, the upper portion
and the sole
together define a void that is configured to securely and comfortably hold a
human foot.
Often, the upper portion and/or sole are/is formed from multiple layers that
can be
stitched or adhesively bonded together. For example, the upper portion can be
made of a
combination of leather and fabric, or foam and fabric, and the sole can be
formed from at
least one layer of natural rubber. Often materials are chosen for functional
reasons, e.g.,
water-resistance, durability, abrasion-resistance, and breathability, while
shape, texture,
and color are used to promote the aesthetic qualities of the shoe.
SUMMARY
[0003] One aspect of the disclosure provides an article of footwear including
a
footwear upper and a sole assembly secured to the footwear upper. The sole
assembly
has a forefoot portion and a heel portion, and includes an outsole, a midsole
disposed on
the outsole and an instability insert disposed between the outsole and the
midsole in the
forefoot portion of the sole assembly. The instability insert causes a
forefoot protrusion
to be defined by the outsole in the forefoot portion of the sole assembly.
[0004] Another aspect of the disclosure provides an article of footwear
including a
footwear upper and a sole assembly secured to the footwear upper. The sole
assembly
has a forefoot portion and a heel portion. The forefoot portion of the sole
assembly is
configured to provide a first period of instability upon receiving the weight
of a user
followed by a second period of stability.
[0005] Implementations of the disclosure may include one or more of the
following
features. In some implementations, the heel portion is configured to at least
partially
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collapse upon receiving the weight of a user and cause the user to rotate the
sole
assembly forward, placing the weight of the user on the forefoot portion of
the sole
assembly. In some implementations, the sole assembly includes an outsole, a
midsole
disposed on the outsole and an instability insert disposed between the outsole
and the
midsole in the forefoot portion of the sole assembly, the instability insert
causing a
forefoot protrusion to be defined by the outsole in the forefoot portion of
the sole
assembly.
[00061 In some implementations, the forefoot portion of the outsole defines a
radius
of curvature of between about 130 mm and about 190 mm (preferably about 160
mm).
The forefoot protrusion can have a height, measured from a lowest point of the
protrusion
to an outer edge of the outsole, of between about 4 mm and about 12 mm (e.g.,
about 8
mm). The instability insert may define a substantially elliptical shape in top
and side
views. In some examples, the instability insert has a thickness of between
about 3 mm
and about 9 mm (e.g., about 6 mm), a length of between about 65 mm and about
85mm
(e.g., about 76 mm), and a width of between about 45 mm and about 55mm (e.g.,
about
50 mm). The instability insert may comprise polyurethane. In some
implementations,
the instability insert has a durometer of between about 15 Asker C and about
20 Asker C.
[0007] In some implementations, the article of footwear includes a heel insert
disposed substantially between the outsole and the midsole in the heel portion
of the sole
assembly, the heel insert configured to collapse under a user's weight. The
heel insert
may comprise at least one of polyurethane and a ethylene-vinyl-acetate
copolymer
(EVA). In some examples, the heel insert has a durometer of between about 42
Asker C
and about 48 Asker C and/or a thickness of between about 10 mm and about 35
mm.
[00081 In yet another aspect, an article of footwear includes a footwear upper
and a
sole assembly secured to the footwear upper. The sole assembly includes an
outsole
defining a substantially convex instability protrusion. The instability
protrusion defines a
radius of curvature of between about 130 mm and about 190 mm. Moreover, the
instability protrusion has a length along the outsole of between about 65 mm
and about
85 mm, a width along the outsole of between about 45 mm and about 55 mm, and a
height, measured from a lowest point of the protrusion to an outer edge of the
outsole, of
between about 4 mm and about 12 mm.
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[0009] Implementations of the disclosure may include one or more of the
following
features. In some implementations, the instability protrusion defines a
substantially
elliptical shape having a length along the outsole of about 76 mm and a width
along the
outsole of about 50 mm. A longitudinal axis of the instability protrusion may
be arranged
at an angle of between about 100 and about 30 with a transverse axis of the
sole
assembly. In some examples, the longitudinal axis of the instability
protrusion is
arranged at an angle of about 20 with the transverse axis of the sole
assembly. The
instability protrusion may define a radius of curvature of about 160 mm and/or
have a
height, measured from a lowest point of the protrusion to an outer edge of the
outsole, of
about 8 mm.
[0010] In some implementations, the sole assembly includes a midsole disposed
on
the outsole and an instability insert disposed between the outsole and the
midsole in the
forefoot portion of the sole assembly. The instability insert defines the
instability
protrusion extending from the outsole in the forefoot portion of the sole
assembly. In
some examples, the instability insert defines a substantially elliptical shape
in top and
side views. Moreover, the instability insert may have a thickness of between
about 3 mm
and about 9 mm, a length of between about 65 mm and about 85 mm, and a width
of
between about 45 mm and about 55 mm. In some examples, the instability insert
comprises polyurethane and/or has a durometer of between about 15 Asker C and
about
20 Asker C.
[0011] In some implementations, the sole assembly includes a midsole disposed
on
the outsole and a heel insert disposed substantially between the outsole and
the midsole in
a heel portion of the sole assembly. The heel insert is configured to collapse
under the
weight of a user. In some examples, the heel insert comprises at least one of
polyurethane and a ethylene-vinyl-acetate copolymer (EVA). Moreover, the heel
insert
may have a durometer of between about 42 Asker C and about 48 Asker C and/or
have a
thickness of between about 10 mm and about 35 mm.
[0012] Another aspect of the disclosure provides an article of footwear that
includes a
footwear upper and a sole assembly secured to the footwear upper. A forefoot
portion of
the sole assembly defines a substantially convex instability protrusion. The
instability
protrusion provides a first period of instability upon receiving the weight of
a user
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followed by a second period of stability after at least partially collapsing
the instability
protrusion under the weight of the user. The instability protrusion has a
length along the
sole assembly of between about 65 mm and about 85 mm and a width along the
sole
assembly of between about 45 mm and about 55 mm.
[0013] In some implementations, the instability protrusion defines a
substantially
elliptical shape having a length along the sole assembly of about 76 mm and a
width
along the sole assembly of about 50 mm. The instability protrusion may have a
height,
measured from a lowest point of the protrusion to an outer edge of the sole
assembly, of
between about 4 mm and about 12 mm. In some examples, the instability
protrusion
defines a radius of curvature of between about 130 mm and about 190 nun at
least along
a transverse axis of the sole assembly. A longitudinal axis of the instability
protrusion
may be arranged at an angle of between about 10 and about 30 with a
transverse axis of
the sole assembly.
[0014] The sole assembly, in some implementations, includes an outsole, a
midsole
disposed on the outsole, and an instability insert disposed between the
outsole and the
midsole in a forefoot portion of the sole assembly. The instability insert
defines the
instability protrusion extending from the outsole. In some examples, the
instability insert
defines a substantially elliptical shape in top and side views. The
instability insert may
have a thickness of between about 3 mm and about 9 mm, a length of between
about 65
mm and about 85 mm, and a width of between about 45 mm and about 55 mm. The
instability insert may comprise polyurethane and/or have a durometer of
between about
15 Asker C and about 20 Asker C.
[0015] The heel portion may be configured to at least partially collapse upon
receiving the weight of a user and cause the user to rotate the sole assembly
forward,
placing the weight of the user on the forefoot portion of the sole assembly.
In some
implementations, the sole assembly includes an outsole, a midsole disposed on
the
outsole, and a heel insert disposed substantially between the outsole and the
midsole in a
heel portion of the sole assembly. The heel insert is configured to collapse
under the
weight of a user. The heel insert may comprise at least one of polyurethane
and a
ethylene-vinyl-acetate copolymer (EVA). Moreover, the heel insert may have a
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durometer of between about 42 Asker C and about 48 Asker C and/or have a
thickness of
between about 10 mm and about 35 mm.
[0016] In yet another aspect, an article of footwear includes a footwear upper
and a
sole assembly secured to the footwear upper. The sole assembly includes a
forefoot
portion of the sole assembly defining a substantially convex instability
protrusion. The
instability protrusion provides a first period of instability upon receiving
the weight of a
user followed by a second period of stability after at least partially
collapsing the
instability protrusion under the weight of the user. The sole assembly also
includes a heel
portion configured to at least partially collapse upon receiving the weight of
a user and
cause the user to rotate the sole assembly forward, placing the weight of the
user on the
forefoot portion of the sole assembly.
[0017] In some implementations, the instability protrusion has a length along
the sole
assembly of between about 65 mm and about 85 mm and a width along the sole
assembly
of between about 45 mm and about 55 mm. In some examples, the instability
protrusion
defines a substantially elliptical shape having a length along the sole
assembly of about
76 mm and a width along the sole assembly of about 50 mm. The instability
protrusion
may have a height, measured from a lowest point of the protrusion to an outer
edge of the
sole assembly, of between about 4 mm and about 12 mm and/or define a radius of
curvature of between about 130 mm and about 190 mm at least along a transverse
axis of
the sole assembly. In some examples, a longitudinal axis of the instability
protrusion is
arranged at an angle of between about 10 and about 30 with a transverse axis
of the sole
assembly.
[0018] The sole assembly, in some implementations, includes an outsole, a
midsole
disposed on the outsole, and an instability insert disposed between the
outsole and the
midsole in a forefoot portion of the sole assembly. The instability insert
defines the
instability protrusion extending from the outsole. The instability insert may
define a
substantially elliptical shape in top and side views. In some examples, the
instability
insert has a thickness of between about 3 mm and about 9 mm, a length of
between about
65 mm and about 85 mm, and a width of between about 45 mm and about 55 mm. The
instability insert may comprise polyurethane and/or have a durometer of
between about
15 Asker C and about 20 Asker C.
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[0019] In some implementations, the sole assembly includes an outsole, a
midsole
disposed on the outsole, and a heel insert disposed substantially between the
outsole and
the midsole in a heel portion of the sole assembly. The heel insert is
configured to
collapse under the weight of a user. The heel insert may comprise at least one
of
polyurethane and a ethylene-vinyl-acetate copolymer (EVA). In some examples,
the heel
insert has a durometer of between about 42 Asker C and about 48 Asker C and a
thickness of between about 10 mm and about 35 mm.
[0020] The details of one or more implementations of the disclosure are set
forth in
the accompanying drawings and the description below. Other aspects, features,
and
advantages will be apparent from the description and drawings, and from the
claims.
DESCRIPTION OF DRAWINGS
[0021] FIGS. 1 and 2 are front perspective views showing the left component of
a
pair of shoes.
[0022] FIG. 3 is a rear view showing the left component of a pair of shoes.
[0023] FIGS. 4 and 5 are rear perspective views showing the left component of
a pair
of shoes.
[0024] FIG. 6 is a top perspective view showing the left component of a pair
of
shoes.
[0025] FIG. 7 is a bottom view of a sole assembly for a left component of a
pair of
shoes.
[0026] FIG. 8 is a top view of the sole assembly of FIG. 7.
[0027] FIG. 9 is a side view of the sole assembly of FIG. 7.
[0028] FIG. 10 is a section view of the sole assembly of FIG. 7 along line 10-
10.
[0029] FIG. 11 is a side view of the sole assembly of FIG. 7.
[0030] FIG. 12 is a rear view of the sole assembly of FIG. 7.
[0031] FIG. 13 is a section view of the sole assembly of FIG. 7 along line 13-
13.
[0032] FIG. 14 is a section view of the sole assembly of FIG. 7 along line 14-
14.
[0033] FIG. 15 is a section view of the sole assembly of FIG. 7 along line 15-
15.
[0034] Like reference symbols in the various drawings indicate like elements.
By
way of example only, all of the drawings are directed to an article of
footwear (e.g., a
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shoe) suitable to be worn on a user's left foot. The invention includes also
the mirror
images of the drawings, i.e. an article of footwear suitable to be worn on the
infant's right
foot.
DETAILED DESCRIPTION
[00351 FIGS. 1-6 illustrate an exemplary article of footwear 100 configured to
promote muscle activity in various areas of the user's body, such as the
gastrocnemii
(calves), quadriceps (thighs), and glutaeus maximus (buttocks), while walking
or running.
While wearing each article of footwear 100, the user generally tries to
maintain a
balanced posture, which promotes greater muscle activity (and optionally fat
burning).
The article of footwear 100 (e.g., shoe, sandal, boot, etc.) includes a
footwear upper 110
and a sole assembly 200 secured to the footwear upper 110. The footwear upper
110 and
the sole assembly 200 together define a void 120 configured to securely and
comfortably
hold a human foot. Although a shoe is shown as an exemplary article of
footwear 100,
the sole assembly 200 may be used for other types of articles of footwear,
including, but
not limited to boots, sandals, flip-flops, etc.
[00361 The footwear upper 110 may be stitched and/or bonded (e.g., by an
adhesive)
to the sole assembly 200. The footwear upper 110 may be constructed of one or
more
leathers, textiles, non-woven materials, and any other suitable material for
receiving and
holding a user's foot. In some examples, the footwear upper 110 includes
moisture-
wicking materials.
[00371 Referring to FIGS. 7-15, the sole assembly 200 provides a subtle
instability
that encourages the user's body to work harder to adapt and maintain a
balanced gait
relative to a generally stable sole assembly, thereby promoting muscle
activity. Referring
to FIGS. 3-10, the sole assembly 200 has a forefoot portion 202 and a heel
portion 204,
and includes an outsole 210 and a midsole 220. The outsole 210 and midsole 220
each
have a respective forefoot portion 212, 222 and a respective heel portion 214,
224
corresponding to the forefoot portion 202 and the heel portion 204 of the sole
assembly
200. In some examples, such as FIGS. 10, 14 and 15, the outsole 210 has a
thickness To
of between about 3 mm and about 7 mm (preferably about 5 mm) and the midsole
220
has a thickness Tm of between about 3 mm and about 20 mm (preferably about 13
mm).
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The outsole 210 can be made of natural rubber or formed of a rubber compound
including isobutylene rubber, butadiene rubber, styrene butadiene rubber
and/or natural
rubber. The outsole 210 has a durometer of between about 40 Shore A and about
70
Shore A (preferably 50 Shore A). The midsole 220 can be made of a polyurethane
or
ethylene vinyl acetate (EVA) and have a durometer of between about 50 Shore A
and
about 70 Shore A (preferably between about 60 Shore A and about 65 Shore A).
[00381 The sole assembly 200 includes an instability insert 230 disposed
substantially
between the outsole 210 and the midsole 220 in the forefoot portion 202 of the
sole
assembly 200. The instability insert 230 creates a forefoot protrusion 216
(e.g., a gently
domed bulge) in the outsole 210, such that the user experiences a slight
rocking (fore-aft
and/or side-to-side) in the forefoot portion 202 of the sole assembly. In some
examples,
the forefoot portion 212 of the outsole 210 defines a radius of curvature R of
between
about 130 mm and about 190 mm (preferably about 160 mm). The forefoot
protrusion
216 may have a height H, measured from a lowest point of the protrusion 216 to
an outer
edge 218 of the outsole 210, of between about 4 mm and about 12 mm (preferably
about
8 mm). The user generally exerts relatively more energy to maintain balance
and over-
come the instability caused by the instability insert 230, as compared to that
experienced
while wearing a conventional stable shoe.
[00391 In some implementations, the instability insert 230 defines an
elliptical shape
in top and side views, as shown in FIGS. 8, 10 and 13. In some examples, the
instability
insert 230 has a thickness Ti of between about 3 mm and about 9 mm (preferably
about 6
mm), a length Li of between about 65 mm and about 85 mm (preferably about 76
mm),
and a width W; of between about 45 mm and about 55 mm (preferably about 50
mm). In
some implementations, the instability insert 230 is arranged such that a
longitudinal axis
235 of the instability insert 230 has an angle (3 with a transverse axis 205
of the sole
assembly 200 of between about 10 and about 30 (preferably about 20 ). The
instability
insert 230 can be made of a polyurethane and have a durometer of between about
10
Asker C and about 25 Asker C (preferably between about 15 Asker C and about 20
Asker
Q. By having a softer durometer for the instability insert 230 relative to the
outsole 210
and the midsole 220, the user initially experiences the instability of the
forefoot
protrusion 216 caused by the instability insert 230 upon contact between the
outsole 210
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and the ground. As the user transfers his/her weight onto the shoe 100, the
instability
insert 230 at least partially collapses between the outsole 210 and the
midsole 220,
thereby at least partially collapsing (preferably fully collapsing) the
forefoot protrusion
216 and allowing the user to experience increased or substantially full
stability within the
forefoot portion 202 of the sole assembly as the shoe 100 bears the weight of
the user.
Consequently, as the user proceeds over a surface (e.g., walk or run) while
wearing a pair
of the shoes 100, the user experiences an initial period of instability while
transferring
his/her weight onto one of the shoe 100 followed by a period of stability when
the
respective shoe 100 bears at least some of the weight of the user. For
example, the
instability insert 230 collapses, thereby collapsing the forefoot protrusion
216 (e.g., such
the outsole 210 has a relatively decreased radius of curvature R) upon
receiving a
threshold load of at least 30 lbs. The instability insert 230 may be
configured to collapse
or squish under other threshold loads as well (e.g., at least 15 lbs, 50lbs,
etc.), so as to
target certain user weight groups. The initial period of instability causes
the user to use
stabilizing muscles and exert more energy relative to a conventional shoe. A
completely
unstable shoe, is generally undesirable, thus the period of stability
proceeding the period
of at least slight instability provides the user with a functional and safe
shoe for
exercising.
[0040] In some implementations, the sole assembly 200 includes a heel insert
240
disposed substantially between the outsole 210 and the midsole 220 in the heel
portion
204 of the sole assembly 200, as shown in FIGS. 9-12 and 15. The heel insert
240 can be
made of polyurethane or a polyolefin, such as an ethylene-vinyl-acetate
copolymer
(EVA), and/or have a durometer of between about 25 Asker C and about 55 Asker
C
(preferably between about 42 Asker C and about 48 Asker Q. The heel insert 240
can
have a thickness Th (FIG 15) of between about 10 mm and about 35 mm
(preferably
about 25 mm). The heel insert 240 not only provides cushioning and comfort for
a user,
but the relatively soft durometer of the heel insert 240, as compared to the
outsole 210
and the midsole 220, allows the heel portion 204 of the sole assembly 200 to
at least
partially collapse under a user's weight, thereby causing the user to shift
his/her weight
toward the forefoot portion 202 of the sole assembly 200. As the user shifts
his/her
weight to the forefoot portion 202 of the sole assembly 200, the user
experiences the
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subtle instability of the forefoot portion 202 (as caused by the forefoot
protrusion 216)
and exerts relatively more energy and/or uses relatively more muscles to
maintain
balance. As the forefoot protrusion 216 collapses or subsides due the weight
transfer of
the user, the user experiences a subsequent period of stability.
[00411 The article of footwear 100 may include a foot bed 300 (FIG. 6) secured
to the
shoe assembly 200 and/or insole 130 in the void 120 defined by the upper 100
and the
shoe assembly 200. The foot bed 300 is compliant to conform to and exhibit the
shape of
the user's foot bottom and portions of outsole 100. The foot bed 300 may be a
foam
sheet with a woven or non-woven fabric covering the foam sheet.
[00421 A number of implementations have been described. Nevertheless, it will
be
understood that various modifications may be made without departing from the
spirit and
scope of the disclosure.