Note: Descriptions are shown in the official language in which they were submitted.
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MULTIPLE RESPONSE PROPERTY FOOTWEAR
Cross Reference to Related Applications
[0001] The present application claims priority to U.S. Provisional Patent
Application No. 61/345,978, filed May 18, 2010, entitled "MULTIPLE RESPONSE
PROPERTY FOOTWEAR," the disclosure of which is hereby incorporated by
reference
in its entirety.
Technical Field
[0002] Embodiments herein relate generally to the field of footwear, and more
particularly to components of performance footwear, such as midsoles, as well
as
methods of making midsoles.
Background
[0003] The sole assembly of athletic footwear generally has a layered
configuration that includes a comfort-enhancing insole, a resilient midsole
formed from a
polymer foam material, and a ground-contacting outsole that provides both
abrasion-
resistance and traction. The midsole imparts cushioning and helps control foot
motion.
[0004] The midsole may be formed from a single-layer polymer foam that extends
throughout the length and width of the footwear. With the exception of a
difference in
thickness between the heel and forefoot areas of the footwear, such a unitary
midsole
has substantially uniform properties. In order to vary the properties of
midsole, some
conventional midsoles incorporate dual- or multi-density or multi-durometer
polymer
foams. For instance, the lateral side of the midsole may be formed from one
foam
material, and the medial side of the midsole may be formed from a second, less-
compressible, denser foam material.
[0005] Generally, the layers of foam are cut, placed, and glued together using
a
vertical or angled seam. This results in an undesirable lever effect during a
footstrike as
the weight of the foot travels over the abrupt transition point between foam
densities or
durometers. The sudden transition from firmer foam to softer foam (or visa
versa) can
result in instabilities in the footstrike, such as over-rapid pronation of the
foot.
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Additionally, this method of construction can require the use of glues that
may contain
volatile organic compounds (VOCs), which may have undesirable environmental
and
health impacts, both for the manufacturer of the footwear and the wearer.
Furthermore,
the use of a glued seam creates a potential site of physical failure, and the
midsole
layers may separate with use.
Brief Description of the Drawings
[0006] Embodiments will be readily understood by the following detailed
description in conjunction with the accompanying drawings. Embodiments are
illustrated by way of example and not by way of limitation in the figures of
the
accompanying drawings.
[0007] Figures 1A, 1 B, 1 C, 1 D, 1 E, and 1 F illustrate examples of multiple
response property midsoles in accordance with various embodiments;
[0008] Figures 2A and 2B illustrate a method of making a multiple response
property midsole, in accordance with various embodiments;
[0009] Figures 3A and 3B illustrate another method of making a multiple
response property midsole, in accordance with various embodiments;
[0010] Figure 4 illustrates another method of making a multiple response
property midsole, in accordance with various embodiments; and
[0011] Figure 5 illustrates another method of making a multiple response
property midsole, in accordance with various embodiments.
Detailed Description of Embodiments
[0012] In the following detailed description, reference is made to the
accompanying drawings which form a part hereof, and in which are shown by way
of
illustration embodiments that may be practiced. It is to be understood that
other
embodiments may be utilized and structural or logical changes may be made
without
departing from the scope. Therefore, the following detailed description is not
to be
taken in a limiting sense, and the scope of embodiments is defined by the
appended
claims and their equivalents.
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[0013] Various operations may be described as multiple discrete operations in
turn, in a manner that may be helpful in understanding embodiments; however,
the
order of description should not be construed to imply that these operations
are order
dependent.
[0014] The description may use perspective-based descriptions such as
up/down, back/front, and top/bottom. Such descriptions are merely used to
facilitate the
discussion and are not intended to restrict the application of disclosed
embodiments.
[0015] The terms "coupled" and "connected," along with their derivatives, may
be
used. It should be understood that these terms are not intended as synonyms
for each
other. Rather, in particular embodiments, "connected" may be used to indicate
that two
or more elements are in direct physical or electrical contact with each other.
"Coupled"
may mean that two or more elements are in direct physical contact. However,
"coupled"
may also mean that two or more elements are not in direct contact with each
other, but
yet still cooperate or interact with each other.
[0016] For the purposes of the description, a phrase in the form "A/B" or in
the
form "A and/or B" means (A), (B), or (A and B). For the purposes of the
description, a
phrase in the form "at least one of A, B, and C' means (A), (B), (C), (A and
B), (A and
C), (B and C), or (A, B and C). For the purposes of the description, a phrase
in the form
"(A)B" means (B) or (AB) that is, A is an optional element.
[0017] The description may use the terms "embodiment" or "embodiments,"
which may each refer to one or more of the same or different embodiments.
Furthermore, the terms "comprising," "including," "having," and the like, as
used with
respect to embodiments, are synonymous.
[0018] Embodiments of the present disclosure are directed to performance
footwear having portions that may help facilitate a more fluid foot movement,
improve
manufacturing and production techniques, and prevent injury to the foot,
ankle, and/or
legs during exercise, such as running, hiking, walking, and other impact-
generating
activities. In various embodiments, multiple response property midsoles and/or
portions
of footwear are provided that may include strategically arranged multiple
response
property areas having blended transition zones disposed there between.
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[0019] In various embodiments, the multiple response property areas (and the
differences between them) may be characterized as having various properties,
such as
density, durometer, specific gravity, and other footwear design
characteristics. In
various embodiments, the blended transition zones between adjacent response
property areas may allow for a variety of biomechanical improvements,
including, but
not limited to, improved impact cushioning, support, and stability, as well as
a more fluid
footstrike motion. As used herein, the term blended transition zone and any
variation
thereof may generally refer to the interlocking, intermingling, and/or
intermixing of
materials (e.g., foams) having different response properties (e.g., densities
or
durometers), such that there is not a definite, clearly defined linear or
planar path
between the materials with different response properties, but rather a gradual
transition
from one defined material/property to another.
[0020] In some embodiments, blending the transition zones in the midsole may
help avoid the lever effect that is common when materials having different
response
properties are glued together, for instance with a vertical or angled seam.
For example,
when a denser or a higher durometer material is positioned directly against a
less dense
or lower durometer foam without a blended transition region, the foot may
undergo an
undesirably rapid and sudden pronation when it travels over the abrupt
transition
between densities. By contrast, the blended transitions in the multiple
response
property midsoles disclosed herein may provide a gradual transition between
the
portions with different material response properties, which in-turn may help
to ensure a
more fluid footstrike motion. In addition, the lack of traditional glued seams
enhances
the strength and integrity of the midsole, while also permitting the different
response
property material areas to be arranged in any desired configuration. Further,
embodiments of the midsole may use a glueless construction method that
effectively
eliminates the VOCs present in the glues typically used to couple the
different materials
in a traditional midsole.
[0021] Figure 1A illustrates an example of a midsole with blended transitions
between areas of differing (e.g., multiple) material response properties
(e.g., density or
durometer) in accordance with various embodiments. In the illustrated
embodiment,
materials of different response properties have been strategically positioned
in a posted
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configuration that may be useful in, for example, athletic shoes, to help
control the rate
of pronation. Midsole 100a may include different response property areas
arranged
from medial to lateral, with, for example, a higher density or durometer
material
disposed in the medial arch region, and transitioning to a less dense or
softer material
toward the lateral side of the midsole. In one embodiment, a first response
property
material 10 may be located in the immediate arch area, with a second response
property material 12 disposed immediately adjacent to (e.g., on the lateral
side of) the
first response property material 10. A blended transition 16 may be disposed
between
the first and second response property materials. In some embodiments, a third
response property material 14 may be positioned adjacent to the second
response
property material 12, and may generally comprise the rest of the midsole 100a.
A
blended transition area 18 may be disposed between the second and third
response
property materials.
[0022] In various embodiments, in transition zones 16 and 18, the different
materials having different response properties may intermingle and blend over
a certain
distance, instead of having a traditional glued seam. In various embodiments,
these
blended transition zones 16 and 18 may help avoid the lever effect, which is
common
with an abrupt transition between materials such as is found with glued seams,
and may
help enhance fluid connection and movement between the different response
property
materials. In one embodiment, first response property material 10 may have a
higher
density or durometer, with second response property material 12 having a
density or
durometer that is less than that of first response property material 10, but
greater than
that of third response property material 14. Such a configuration may provide
support
and stability for a user who over-pronates during a stride, for example. As
illustrated,
the strategic alignment of the different material response properties and
resulting
blended transition zones may provide a midsole that may be useful in providing
a
combination of impact absorption, flexibility, and stability, for instance,
for walking,
jogging, comfort, cross-training, such as in running shoes, hiking boots, or
trail shoes.
[0023] Figure 1 B illustrates another example of a multiple response property
midsole with blended transitions in accordance with various embodiments. In
the
illustrated example, a first response property material 10 may be located at
the sides of
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the midfoot region of the midsole 100b, for instance generally in the medial
arch region
and opposite the arch region near the lateral edge of the foot. In various
embodiments,
second response property material 12 may generally surround first response
property
material 10, with the remainder of the midsole comprising third response
property
material 14. In the illustrated embodiment, blended transition zones 16 and 18
may be
disposed between the different response property materials, 10, 12, and 14,
and may
contribute to the fluid motion, strength, and mechanics of midsole 100b. For
example,
as described above, first response property material 10 may have a higher
density or
durometer than second response property material 12, which in turn may have a
higher
density or durometer than third response property material 14. In some
embodiments,
this configuration may provide lateral stability, which may be useful, for
instance, on
rocky or uneven terrain, or for a user who is prone to either over-pronation
or over-
supination. In various embodiments, this configuration also may provide
enhanced
flexibility, cushioning, and comfort in the heel and forefoot portions of the
midsole. As
illustrated, the strategic alignment of the different material response
properties and
resulting blended transition zones may provide a midsole that may be useful in
providing a combination of impact absorption, flexibility, and stability, for
instance, for
jogging or running shoes, hiking boots, or trail shoes.
[0024] Figure 1C illustrates another example of a multiple response property
midsole with blended transitions in accordance with various embodiments. In
this
example, first response property material 10 may be located at the lateral and
medial
sides of the midfoot and the heel of midsole 100c, for instance generally in a
horseshoe-like pattern. In various embodiments, second response property
material 12
may generally surround first response property material 10, and third response
property
material 14 may comprise the rest of the midsole. In various embodiments,
blended
transition zones 16 and 18 may be disposed between the different response
property
materials, and may contribute to the fluid motion, strength, and mechanics of
the
midsole. For example, first response property material 10 may be of a higher
density or
durometer than second response property material 12 and third response
property
material 14, which may provide stability in the side and rear areas of the
foot. This may
be useful, for instance, on rocky or uneven terrain, while providing enhanced
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pronation/supination prevention, enhanced flexibility, and cushioning and
comfort in the
central and forefoot regions of the midsole. As illustrated, the strategic
alignment of the
different response property materials and resulting blended transition zones
may
provide a midsole that may be useful in providing stability, for instance, for
hiking boots
or trail shoes.
[0025] Figure 1 D illustrates yet another multiple response property midsole
100d
with blended transitions in accordance with various embodiments. As
illustrated, the
strategic placement of the different response property material areas may
include
arranging a first response property material 10 in the heel region, a second
response
property material 12 in the mid-foot region, and a third response property
material 14 in
the toe region, with blended transition zones 16 and 18 formed between the
different
response property material areas. Such an embodiment may be useful, for
instance, in
sandals where a higher density or durometer material may be used as the first
response
property material 10, for instance to improve impact absorbance of the heel
region,
support, and durability. The second response property material 12 may have a
density
or durometer less than that of the first response property, and may be
positioned to
provide additional support and cushioning for the midfoot area. Finally, the
third
response property material 14 may be the least dense of the three response
property
materials, and may be placed to provide enhanced comfort and flexibility in
the forefoot
region.
[0026] Figure 1 E illustrates still another multiple response property midsole
with
blended transitions in accordance with various embodiments. As illustrated,
different
response property material areas may be arranged or layered vertically within
the
midsole 100e, from bottom to top. In some embodiments, a layer of second
response
property material 12 may be sandwiched between first response property
material 10
and third response property material 14. In some embodiments, first blended
transition
16 may be disposed between first response property layer 10 and second
response
property layer 12, and second blended transition zone 18 may be disposed
between
second response property layer 12 and third response property layer 14. In one
embodiment, the response properties may be selected such that a less dense or
lower
durometer (e.g., softer) third response property material 14 may be used as
the upper
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layer to provide comfort, whereas second 12 and first 10 response property
materials
may have higher densities or durometers, for instance to provide durability,
support and
resilience. Such an embodiment may be particularly useful in comfort shoes,
work
shoes, etc.
[0027] Figure 1 F illustrates another example of a multiple response property
midsole with blended transitions in accordance with various embodiments. As
shown in
the illustrated embodiment, midsole 100f may have multiple response property
materials arranged to enhance lateral stability. In the illustrated example,
lateral
stability bars of first response property material 10 may be disposed at the
medial and
lateral edges of the midsole. In various embodiments, the center portion of
the midsole
may include a third response property material 14, and second response
property
material 12 may be disposed there between. In various embodiments, blended
transition 16 may be disposed between first response property material 10 and
second
response property material 12, and second blended transition 18 may be
disposed
between second response property material 12 and third response property
material 14.
In various embodiments, such an arrangement may provide a balance of
cushioning
(e.g., where third response property material 14 is a lower density or
durometer foam)
and stability (e.g., where first response property material 10 is a higher
density or
durometer foam).
[0028] In the foregoing embodiments, one of skill in the art will appreciate
that,
although three different response property materials/areas are illustrated in
each
example, any number of response property areas may be used, for instance 2, 3,
4, 5,
6, or even more response property areas. Such different response property
areas may
be arranged in a number of strategic configurations. For example, a low
density or
durometer material may be used wherever extra softness or cushioning is
needed, such
as in the forefoot area, heel layer, or upper layer of the midsole, or for use
when the
user has an injury or otherwise requires more cushioning. In another example,
a higher
density or durometer material may be included in any area requiring firm
support, extra
stability, or extra durability, such as in the arch region, the midfoot
region, the heel
region, or the lower portions of the midsole. In some embodiments, the
specific
configuration of the midsole may be customized to suit the needs, footstrike
pattern, or
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running style of an individual user. In other embodiments, the blended
transitions of the
midsole may allow the shoe to respond to the individual needs of a particular
user or the
particular terrain conditions.
[0029] Although the response property areas are referred to herein as low,
medium, and high (e.g., as it relates to a material response property that is
density or
durometer), one of skill in the art will appreciate that these terms are
relative. In one
embodiment where the material response property is durometer, for instance,
the low,
medium, and high identifiers may correspond to 55, 60, and 65 Asker C; or 55,
65, and
75 Asker C. In other embodiments, greater or lower response property materials
also
may be used to suit the desired application.
[0030] In embodiments, changing the material hardness of the midsole may
change the activity in various lower extremity muscles, such as rectus
femoris, biceps
femoris, medial gastrocnemius, and tibialis anterior. For instance, when
running on a
dense midsole, the tibialis anterior muscle may exert significantly more force
before the
heel strike and less force following the heel strike than when running on a
medium
midsole. Additionally, using shoes with a denser midsole may reduce the energy
dissipated at the metatarsophalangeal joints and aid in improving jumping
performances
and economy of foot movement. Thus, in various embodiments, the response may
be
varied in particular regions of the midsole and/or other portions of the
footwear for a
variety of reasons.
[0031] Figures 1G and 1H illustrate a multiple response property article of
footwear in accordance with various embodiments, where the multiple response
property materials comprise not only the midsole, but also portions of, for
example, the
heel cup 70 and/or upper 80. For example, midsole 100g may also extend upward
around the heel cup region 70, which may provide greater heel stability and/or
protection. As illustrated, the strategic placement of the different response
property
material areas may include arranging a first response property material 10 in
the heel
region of the midsole, a second response property material 12 in the foot bed
region of
the midsole, and a third response property material 14 in heel cup region,
with blended
transition zones 16 and 18 formed between the different response property
material
areas. In some embodiments, the multiple response property materials may
extend to
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encompass all or a portion of the vamp or upper 80, such as the toe box, the
instep, the
tongue, or the ankle collar, or all or part of the insole or, outsole (not
shown).
[0032] In other embodiments, the midsole material may extend around and/or
over the instep, for instance to provide greater protection and stability
through the
midfoot region. In still other embodiments, the midsole material may extend
around
and/or over the forefoot region, for instance to provide protection to the
toes. In some
embodiments, the midsole material may extend around the entire foot and may
form a
part of or all of the footwear upper, for instance in boots or shoes that
provide extra
ankle support or foot protection. In some embodiments, the portion of the
midsole
material that extends past the midsole may include a less dense material, such
as an
extra soft response property material.
[0033] In other embodiments, methods of making a multiple response property
midsoles and other footwear portions are provided. Conventional multiple
response
property midsoles are typically constructed by stock-fitting or gluing
together individual
material components prior to final molding or after final molding. This leaves
a distinct
line and a generally solid border between the different response property
materials,
which border is often delineated by a glue seam. By contrast, the disclosed
methods
may allow the different response property material areas to have blended
transition
zones, which again may produce a more fluid, gradual change in the midsole
response
property as detected by the foot.
[0034] In various embodiments, the different response properties may be
achieved by a variety of materials suitable for midsole construction. In some
embodiments, polymer foam pellets may be arranged such that compression
molding of
the pellets may result in blending of the different response properties in the
transition
zones, as illustrated in the examples shown in Figures 1A-1H. In some
embodiments,
the polymer foam pellets may be ethylene vinyl acetate (EVA) pellets. EVA is a
polymer
that may approach elastomeric materials in softness and flexibility, yet may
be
processed like other thermoplastics. The material has good clarity and gloss,
barrier
properties, low-temperature toughness, stress-crack resistance, hot-melt
adhesive
waterproof properties, and resistance to UV radiation. In other embodiments,
the
midsole may include one or more other types of material, such as rubberized
EVA,
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polyurethane, and/or any other midsole/footwear construction material known to
those
of skill in the art.
[0035] Although the foregoing examples illustrate embodiments having three
distinct response property materials, one of skill in the art will appreciate
that some
embodiments, of the midsole may include only two different response property
materials, whereas other embodiments may include four, five, six, or even more
response property materials. In addition, these materials may be distributed
about the
midsole wherever a particular response property is desired. For instance, more
or less
of the midsole may comprise higher density or durometer foams than in the
illustrated
examples. Additionally, in some embodiments, lower or higher density or
durometer
materials may be incorporated under the metatarsals, for instance, to form
crash pads.
[0036] In various embodiments, multiple response property midsoles with
blended transition areas may be formed in a number of ways, for example using
known
midsole forming techniques, such as pre-form and compression molding,
injection
molding, pellet pour, and the like. In one embodiment, as illustrated in
Figures 2A and
2B, the midsole may be formed by arranging foam pellets of different response
properties in a specifically designed jig. As illustrated, a jig 200 having
one or more
compartments may be positioned within a midsole mold 50. EVA or other midsole
forming pellets may be poured into the compartments 20, 21 of jig 200, as well
as into a
space 22 created between jig 200 and mold 50. As illustrated, a jig with two
different
compartments may allow for the midsole to be formed using pellets 24, 26, 28
of three
different response properties, although other jig configurations are
contemplated that
have more or fewer compartments.
[0037] In various embodiments, the different response properties of pellets
24,
26, 28 may be color-coded for visual determination and placement in the proper
compartments 20, 21, 22 of the jig 200. In some embodiments, once the pellets
24, 26,
28 are positioned correctly, the jig 200 may then be removed by lifting in a
vertical
direction, thereby allowing the pellets 24, 26, 28 to intermingle, or at least
providing the
potential to intermingle during the midsole formation process. The
strategically
positioned pellets 24, 26, 28 in the mold may then be subjected to a pre-form
process,
which includes addition of heat and temperature to activate the blowing agent
in, for
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example, the EVA to induce the intended properties. During the pre-form
process,
blended transition zones are formed by virtue of contiguity between the
different pellets,
which allows for some flow or migration of the differing response property
materials
between strategic response property zones. The blocker or pre-form may then be
compression molded, giving the midsole its final dimensions.
[0038] In various embodiments, blended transition zones formed during the pre-
form and molding process may result in a mechanical coupling of the different
response
property areas without using an adhesive. Further, in some embodiments, the
absence
of harsh, inflexible lines/seams between traditional multi-density midsoles
may provide a
more fluid and gradual tactile feel as the foot naturally pronates during the
running or
walking motion. In some embodiments, different colors may be chosen for the
different
response property pellets 24, 26, 28, which may allow for the blended
transition zones
to be visually distinguishable, and which may also give the final midsole a
unique look.
[0039] Figures 3A and 3B illustrate side and top views of an example of
another
method for forming midsoles in accordance with various embodiments. In various
embodiments, a cage 300 may be inserted into mold 50, and may be configured to
separate different response property pellets. In various embodiments, cage 300
may
surround second response property pellets 36, and may separate them from first
response property pellets 34 and third response property pellets 38. In some
embodiments, cage 300 may be generally shaped like jig 200 in the previous
embodiment, forming one or more compartments for the different response
property
pellets. In some embodiments, the cage may be configured to melt during the
pre-form
formation stage, thereby allowing the cage material to integrate with and
become part of
the midsole. In various embodiments, the melting of cage 300 may allow
different
response property pellets 34, 36, 38 to intermingle at the cage borders and
form
blended transition zones between differing response property material areas.
As in the
previous embodiment, the blocker or pre-form may then be compression molded,
giving
the midsole its final dimensions.
[0040] Figure 4 illustrates an example of another method for forming midsoles
in
accordance with various embodiments. A quantity of pellets of each desired
response
property may be lightly molded prior to the pre-form stage, thereby forming
one or more
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pre-molds 44, 46, 48, of a material that will achieve a desired response
property. One
or more different pre-molds 44, 46, 48 may then be placed within the mold 50
in the
desired configuration. In some embodiments, given that the pre-mold does not
significantly change the pellet characteristics, but only temporarily holds
like response
property pellets in a desired configuration for placement in the mold, during
the pre-form
process the pellets/materials may still flow into adjacent response property
materials,
and thereby form the blended transition zones.
[0041] In various embodiments, the pre-molds 44, 46, 48 may be formed in a
variety of ways. In one example, the pre-mold may include gently and briefly
heating
certain response property foam pellets in an individual mold such that that
the pellets
adhere to one another to form the desired pre-form shape. In particular
embodiments,
the pellets may be heated to approximately 130 C for about 4 minutes, and then
cooled
prior to placement in the pre-form mold. In some embodiments, slight pressure
may be
added to ensure that a one-piece formation of the pre-form is achieved. In
some
embodiments, a binder may be used to hold the response property material
pellets
together for strategic placement in the mold. The binder may be selected such
that it
may mix with the multiple response property materials during the pre-form
process,
similar to the aforementioned cage embodiments where the cage material is
selected to
melt and integrate with the pre-form.
[0042] In one embodiment, the pre-molds 44, 46, 48 may be placed in the pre-
form mold, for instance, with a higher response property pre-mold 44 in the
medial arch
position, and with a medium response property pre-mold 46 sandwiched between
the
higher response property pre-mold 44 and the low response property pre-mold
48,
which may be placed in the lateral position. The pre-molds 44, 46, 48 may then
undergo the pre-form treatment and allow the different response property
materials to
intermingle and form the blended transition zones. As in the previous
embodiments, the
blocker or pre-form may then be compression molded, giving the midsole its
final
dimensions.
[0043] Figure 5 illustrates yet another example method for forming midsoles in
accordance with various embodiments. Similar to the embodiment described with
respect to Figure 4, a single pre-mold 46 may be positioned within the pre-
form mold in
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order to control placement of other lose pellets 54 and 58 having different
response
properties. For example, the pre-mold 46 may be made from a second or a medium-
response property pellet, and may be positioned within the pre-form mold such
that it
creates one or more partitions within the pre-form mold. Pellets 54 and 58 of
different
response properties may be disposed in the areas adjacent to the pre-mold. In
the pre-
form process, the different response property materials may intermingle to
thereby form
a blended transition zone. As in the previous embodiments, the blocker or pre-
form
may then be compression molded, giving the midsole its final dimensions.
[0044] In various embodiments, different response property separation
techniques may be used in order to strategically place the different response
properties
in/on the midsole to accomplish the desired effect of manufacturing a multiple
response
property midsole having blended transitions between the materials of different
response
properties. Further, the various examples illustrated and described herein may
be used
together as needed (e.g., use of a jig with different pre-molds, etc.).
Finally, though
certain formed midsoles with strategically positioned response property areas
have
been illustrated, a variety of different response property placements are
possible
depending on the particular need.
[0045] Although the foregoing examples illustrate methods of making midsoles
having three distinct response property materials, one of skill in the art
will appreciate
that some embodiments, the methods may be adapted for making midsoles that may
include only two different response property materials, or midsoles that may
include
four, five, six, or even more response property materials.
[0046] Although certain embodiments have been illustrated and described
herein,
it will be appreciated by those of ordinary skill in the art that a wide
variety of alternate
and/or equivalent embodiments or implementations calculated to achieve the
same
purposes may be substituted for the embodiments shown and described without
departing from the scope. Those with skill in the art will readily appreciate
that
embodiments may be implemented in a very wide variety of ways. This
application is
intended to cover any adaptations or variations of the embodiments discussed
herein.
Therefore, it is manifestly intended that embodiments be limited only by the
claims and
the equivalents thereof.
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