U.S. patent application number 16/260774 was filed with the patent office on 2019-06-06 for sole assembly formed of multiple preforms.
The applicant listed for this patent is NIKE, Inc.. Invention is credited to Thienchai Chaisumrej, Yu-Chen Lin, Tee L. Wan, Chia-Yi Wu.
Application Number | 20190168475 16/260774 |
Document ID | / |
Family ID | 53002804 |
Filed Date | 2019-06-06 |
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United States Patent
Application |
20190168475 |
Kind Code |
A1 |
Wan; Tee L. ; et
al. |
June 6, 2019 |
Sole Assembly Formed of Multiple Preforms
Abstract
A sole assembly may be formed by a method that includes
positioning a plurality of preforms having different colors
together to form a sole assembly preform and placing the sole
assembly preform in a recess in a first portion of a mold assembly.
The sole assembly preform is subjected to heat for a predetermined
amount of time such that the plurality of preforms bond to one
another to form a sole assembly.
Inventors: |
Wan; Tee L.; (Portland,
OR) ; Chaisumrej; Thienchai; (Bangkok, TH) ;
Wu; Chia-Yi; (Long An Province, VN) ; Lin;
Yu-Chen; (Taipei City, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
NIKE, Inc. |
Beaverton |
OR |
US |
|
|
Family ID: |
53002804 |
Appl. No.: |
16/260774 |
Filed: |
January 29, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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14252045 |
Apr 14, 2014 |
10226906 |
|
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16260774 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B29D 35/0054 20130101;
B29D 35/142 20130101; A43B 13/16 20130101; B29D 35/04 20130101;
A43B 13/184 20130101; A43B 7/148 20130101; A43B 13/26 20130101;
A43B 13/125 20130101 |
International
Class: |
B29D 35/00 20060101
B29D035/00; B29D 35/14 20060101 B29D035/14; A43B 13/12 20060101
A43B013/12; B29D 35/04 20060101 B29D035/04 |
Claims
1. A sole assembly, comprising: a core portion including a lower
surface and ribs extending downward from the lower surface, wherein
the ribs define a shoulder extending about at least a portion of
the core portion; a first insert contained within and bonded to the
core portion; and a perimeter portion bonded to the core portion,
wherein the perimeter portion forms at least a portion of an outer
periphery of the sole assembly, wherein the perimeter portion
includes an aperture that defines an interior lip, and wherein the
interior lip is seated on the shoulder of the core portion.
2. The sole assembly according to claim 1, wherein an outer
peripheral edge of the first insert is completely surrounded by the
core portion and contained within a first interior recess defined
by the ribs of the core portion.
3. The sole assembly according to claim 1, wherein the perimeter
portion completely surrounds an outer periphery of the core
portion.
4. The sole assembly according to claim 1, wherein a surface of the
aperture abuts an exterior perimeter of the ribs.
5. The sole assembly according to claim 1, wherein lower surfaces
of the core portion, the first insert, and the perimeter portion
include a plurality of grooves and lugs or projections.
6. The sole assembly according to claim 1, wherein the core portion
has a first color, the first insert has a second color different
from the first color, and the perimeter portion has a third color
different from the first color and the second color.
7. The sole assembly according to claim 1, wherein each of the core
portion, the first insert, and the perimeter portion is an ethyl
vinyl acetate material.
8. The sole assembly according to claim 1, wherein the perimeter
portion forms an entire outer periphery of the sole assembly.
9. The sole assembly according to claim 1, wherein the core
portion, the first insert, and the perimeter portion have different
hardnesses from one another.
10. The sole assembly according to claim 1, wherein the first
insert is located in a forefoot region or in a heel region of the
sole assembly.
11. The sole assembly according to claim 1, wherein the first
insert extends from a midfoot region to a forefoot region of the
sole assembly.
12. The sole assembly according to claim 1, further comprising: a
second insert contained within and bonded to the core portion.
13. The sole assembly according to claim 12, wherein an outer
peripheral edge of the second insert is completely surrounded by
the core portion.
14. The sole assembly according to claim 12, further comprising: a
third insert contained within and bonded to the core portion.
15. The sole assembly according to claim 14, wherein an outer
peripheral edge of each of the second insert and the third insert
is completely surrounded by the core portion.
16. The sole assembly according to claim 1, wherein lower surfaces
of the core portion, the first insert, and the perimeter portion
form a grid of hexagonal projections.
17. A sole assembly, comprising: a core portion including a lower
surface and ribs extending downward from the lower surface, wherein
the ribs define a shoulder extending about at least a portion of
the core portion; a first insert contained within and bonded to the
core portion, wherein an outer peripheral edge of the first insert
is completely surrounded by the core portion and contained within a
first interior recess defined by the ribs of the core portion; and
a second insert contained within and bonded to the core portion,
wherein an outer peripheral edge of the second insert is completely
surrounded by the core portion and contained within a second
interior recess defined by the ribs of the core portion.
18. The sole assembly according to claim 17, wherein: (a) the first
insert is located in a forefoot region of the sole assembly and the
second insert is located in a heel region of the sole assembly; or
(b) the first insert is located in a forefoot region of the sole
assembly and the second insert extends from a midfoot region to a
forefoot region of the sole assembly; or (c) the first insert is
located in a heel region of the sole assembly and the second insert
extends from a midfoot region to a forefoot region of the sole
assembly.
19. The sole assembly according to 17, further comprising: a third
insert contained within and bonded to the core portion, wherein an
outer peripheral edge of the third insert is completely surrounded
by the core portion and contained within a third interior recess
defined by the ribs of the core portion.
20. The sole assembly according to claim 19, wherein the first
insert is located in a forefoot region of the sole assembly, the
second insert extends from a midfoot region to a forefoot region of
the sole assembly, and the third insert is located in a heel region
of the sole assembly.
Description
RELATED APPLICATION DATA
[0001] This application is a continuation of U.S. patent
application Ser. No. 14/252,045 filed Apr. 14, 2014 and entitled
"Method of Manufacturing Sole Assembly Formed of Multiple
Preforms." U.S. patent application Ser. No. 14/252,045 is entirely
incorporated herein by reference.
FIELD OF THE INVENTION
[0002] Aspects of this invention relate generally to a method of
manufacturing a sole assembly, and, in particular, to a method of
manufacturing a sole assembly formed of multiple preforms having
different colors.
BACKGROUND OF THE INVENTION
[0003] Conventional articles of athletic footwear include two
primary elements, an upper and a sole assembly. The upper provides
a covering for the foot that comfortably receives and securely
positions the foot with respect to the sole assembly. In addition,
the upper may have a configuration that protects the foot and
provides ventilation, thereby cooling the foot and removing
perspiration. The sole assembly is secured to a lower portion of
the upper and is generally positioned between the foot and the
ground. In addition to attenuating ground reaction forces, the sole
assembly may provide traction, control foot motions (e.g., by
resisting over pronation), and impart stability, for example.
Accordingly, the upper and the sole assembly operate cooperatively
to provide a comfortable structure that is suited for a wide
variety of activities, such as walking and running. An insole may
be located within the upper and adjacent to a plantar (i.e., lower)
surface of the foot to enhance footwear comfort, and is typically a
thin, compressible member.
[0004] The sole assembly may incorporate multiple layers. Some
footwear include only a midsole, while others may also include an
outsole secured to a bottom surface of the midsole. The midsole,
which is conventionally secured to the upper along the length of
the upper, is primarily responsible for attenuating ground reaction
forces. The midsole may also form the ground-contacting element of
footwear. In such embodiments, the midsole may include texturing,
such as projections and recesses or grooves, in order to improve
traction. The outsole, when present, forms the ground-contacting
element and may be fashioned from a durable, wear-resistant
material.
[0005] The midsole may be primarily formed from a resilient,
polymer foam material, such as ethylvinylacetate (EVA), that
extends throughout the length of the footwear. The properties of
the polymer foam material in the midsole are primarily dependent
upon factors that include the dimensional configuration of the
midsole and the specific characteristics of the material selected
for the polymer foam, including the density of the polymer foam
material. By varying these factors throughout the midsole, the
relative stiffness and degree of ground reaction force attenuation
may be altered to meet the specific demands of the activity for
which the footwear is intended to be used. In addition to polymer
foam materials, conventional midsoles may include, for example, one
or more fluid-filled bladders and moderators.
[0006] The sole assembly may be formed of multiple portions, with
some or all of the portions having different colors. When EVA is
formed in a mold assembly the color lines between the different
colored portions may bleed, decreasing the aesthetic appeal of the
footwear.
[0007] It would be desirable to provide a method of manufacturing a
sole assembly for an article of footwear that reduces or overcomes
some or all of the difficulties inherent in prior known processes.
Particular objects and advantages will be apparent to those skilled
in the art, that is, those who are knowledgeable or experienced in
this field of technology, in view of the following disclosure of
the invention and detailed description of certain embodiments.
SUMMARY
[0008] The principles of the invention may be used to advantage to
provide a method of manufacturing a sole assembly formed of
multiple preforms. In accordance with certain embodiments, the
preforms have different colors.
[0009] In accordance with a first aspect, a method of forming a
sole assembly includes positioning a plurality of preforms having
different colors together to form a sole assembly preform and
placing the sole assembly preform in a recess in a first portion of
a mold assembly. The sole assembly preform is subjected to heat for
a predetermined amount of time such that the plurality of preforms
bond to one another to form a sole assembly.
[0010] In accordance with another aspect, a method of forming a
sole assembly includes positioning a first preform having a first
color, a second preform having a second color, and a third preform
having a third color together to form a sole assembly preform. The
sole assembly preform is placed in a recess in a first portion of a
heated mold assembly. The mold assembly is closed such that a
second portion of the mold assembly is above and in contact with
the first portion. The sole assembly preform is subjected to heat
for a predetermined amount of time such that the first, second, and
third preforms bond to one another to form a sole assembly. The
mold assembly is opened the sole assembly is removed from the mold
assembly
[0011] In accordance with a further aspect, a method of forming a
sole assembly includes forming a first preform having a first color
in a recess of a first mold assembly, with a bottom surface of the
recess including surface irregularities. A plurality of second
preforms having a second color are formed in first recesses of a
second mold assembly. A third preform having a third color is
formed in a second recess of the second mold assembly. The first
preform, the second preforms, and the third preform are positioned
together to form a sole assembly preform. The sole assembly preform
is placed in a recess in a first portion of a heated third mold
assembly. The third mold assembly is closed such that a second
portion of the third mold assembly is above and in contact with the
first portion. The sole assembly preform in the third mold assembly
is subjected to heat for a predetermined amount of time such that
the first, second, and third preforms bond to one another to form a
sole assembly. The third mold assembly is opened and the sole
assembly is removed from the third mold assembly. The sole assembly
is allowed to cool, and is then trimmed.
[0012] Features and advantages of manufacturing sole assemblies for
footwear as disclosed here will be further understood from the
following detailed disclosure of certain embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is an elevation view of an article of footwear
including an upper and a sole assembly.
[0014] FIG. 2 is a plan view of a bottom of the sole assembly of
FIG. 1.
[0015] FIG. 3 is a perspective view in exploded form of the sole
assembly of FIG. 1.
[0016] FIG. 4 is a perspective view of a first mold assembly used
to form a core portion of the sole assembly of FIG. 3.
[0017] FIG. 5 is a perspective view of a second mold assembly used
to form inserts and a perimeter portion of the sole assembly of
FIG. 3.
[0018] FIG. 6 is a section view of the bottom plate, sidewall
plate, and core plate of the mold assembly of FIG. 5 seen in a
closed position and abutting relationship.
[0019] FIG. 7 is a section view of the bottom plate, sidewall
plate, core plate, and top plate of the mold assembly of FIG. 5
seen in a closed position and abutting relationship.
[0020] FIG. 8 is an elevation view of a third mold assembly having
a top plate and a bottom plate, shown in exploded form with a
preform prior to its positioning in the bottom plate.
[0021] FIG. 9 is an elevation view of the third mold assembly of
FIG. 8, shown with the preform in a recess in the bottom plate.
[0022] FIG. 10 is an elevation view of the third mold assembly of
FIG. 8, shown in a closed condition.
[0023] The figures referred to above are not drawn necessarily to
scale, should be understood to provide a representation of
particular embodiments of the invention, and are merely conceptual
in nature and illustrative of the principles involved. Some
features of the mold assemblies used to manufacture a sole assembly
have been enlarged or distorted relative to others to facilitate
explanation and understanding. The same reference numbers are used
in the drawings for similar or identical components and features
shown in various alternative embodiments. Mold assemblies for a
sole assembly and methods of manufacture for such a sole assembly
as disclosed herein would have configurations and components
determined, in part, by the intended application and environment in
which they are used.
DETAILED DESCRIPTION OF CERTAIN PREFERRED EMBODIMENTS
[0024] An article of footwear 10 is depicted in FIG. 1 as including
an upper 12 and a sole assembly 14. For purposes of reference in
the following description, footwear 10 may be divided into three
general regions: a forefoot region 16, a midfoot region 18, and a
heel region 20. Regions 16-20 are not intended to demarcate precise
areas of footwear 10. Rather, regions 16-20 are intended to
represent general areas of footwear 10 that provide a frame of
reference during the following discussion. Although regions 16-20
apply generally to footwear 10, references to regions 16-20 also
may apply specifically to upper 12, sole assembly 14, or individual
components within either upper 12 or sole assembly 14.
[0025] Upper 12 defines a void or chamber for receiving a foot. For
purposes of reference, upper 12 includes a lateral side 22, an
opposite medial side 24, and a vamp or instep area 26. Lateral side
22 is positioned to extend along a lateral side of the foot (i.e.,
the outside) and generally passes through each of regions 16-20.
Similarly, medial side 24 is positioned to extend along an opposite
medial side of the foot (i.e., the inside) and generally passes
through each of regions 16-20. Upper 12 may also include a closure
mechanism, such as lace 28. Upper 12 also includes an ankle opening
30 that provides the foot with access to the void within upper
12.
[0026] Upper 12 may also include an insole (or sockliner, not
shown), which is generally a thin, compressible member located
within the void for receiving the foot and proximate to a lower
surface of the foot. Typically, the insole, which is configured to
enhance footwear comfort, may be formed of foam, and optionally a
foam component covered by a moisture wicking fabric or textile
material. Further, the insole or sockliner may be glued or
otherwise attached to the other components of footwear 10, although
it need not be attached, if desired.
[0027] Sole assembly 14 may be directly secured to upper 12 with an
adhesive, for example. Suitable adhesives are well known in the art
and need not be discussed in greater detail here. Sole assembly 14
may be secured to upper 12 with any other suitable fastening means,
and such other suitable means of sole assembly 14 to upper 12 will
become readily apparent to those skilled in the art, given the
benefit of this disclosure.
[0028] It is to be appreciated that in certain embodiments, sole
assembly 14 may serve as a midsole, with an outsole (not shown)
being secured to the bottom surface of the midsole. In other
embodiments, as illustrated here, the bottom surface of sole
assembly 14 serves as the ground-engaging portion (or other contact
surface-engaging portion) of footwear 10.
[0029] Sole assembly 14 is responsible for attenuating ground (or
other contact surface) reaction forces to lessen stresses upon the
foot and leg, and absorb energy. Sole assembly 14 may also
beneficially utilize such ground reaction forces for more efficient
toe-off, and control potentially harmful foot motions, such as over
pronation. Sole assembly 14 also forms a ground-engaging portion
(or other contact surface-engaging portion) of sole assembly 10. As
noted above, in certain embodiments there is a separate outsole
member attached to the bottom surface of a midsole of sole assembly
14, while in other embodiments there is no separate outsole member
of the sole assembly. The bottom surface of sole assembly 14 may
include texturing to improve traction.
[0030] Sole assembly 14 is formed of a plurality of components
having different colors. The method used to form the sole assembly
from a plurality of preforms having different colors reduces the
bleeding between the different colored portions, thereby enhancing
the aesthetics of sole assembly 14. The plurality of components may
also have, in addition to different colors, different physical
properties or performance characteristics. For example, the
hardness of the various components may be different. It is to be
appreciated that any of the known physical properties or
performance characteristics for sole assemblies can be different
for the different components of sole assembly 14, thereby altering
the support, cushioning, load carrying capability, wear
characteristics, and tread life of sole assembly 14, for example.
Other suitable physical properties or performance characteristics
will become readily apparent to those skilled in the art, given the
benefit of this disclosure.
[0031] As seen in the embodiment illustrated in FIG. 2, sole
assembly 14 includes a first core portion 32, one or more inserts
34, and a perimeter portion 36. Core portion 32 is formed of a
first color, inserts 34 are formed of a second color, and perimeter
portion 36 is formed of a third color. While three colors are used
in this embodiment, it is to be appreciated that any number of
different colors may be used for the various components of sole
assembly 14 in accordance with the method of manufacture described
below.
[0032] In certain embodiments, core portion 32, inserts 34, and
perimeter portion 36 may be formed of injection phylon (Ethylene
Vinyl Acetate or "EVA"). The EVA may have a Vinyl Acetate (VA)
level between approximately 9% and approximately 40%. Suitable EVA
resins include Elvax.RTM., provided by DuPont, and Engage, provided
by the Dow Chemical Company, for example. In certain embodiments,
the EVA may be formed of a combination of high melt index and low
melt index material. For example, the EVA may have a melt index
between approximately 1 and approximately 50.
[0033] The EVA may also include various components including a
blowing agent. The blowing agent may have a percent weight between
approximately 10% and approximately 20%. Suitable blowing agents
include azodicarboamide, for example. In certain embodiments, a
peroxide-based curing agent, such as dicumyl peroxide may be used.
The amount of curing agent may be between approximately 0.6% and
approximately 1.5%. The EVA may also include homogenizing agents,
process aids, and waxes. For example, a mixture of light aliphatic
hydrocarbons such as Struktol.RTM. 60NS may be included. The EVA
may also include other constituents such as a release agent (e.g.,
stearic acid), activators (e.g., zinc oxide), fillers (e.g.,
magnesium carbonate), pigments, and clays.
[0034] As illustrated in FIG. 2, perimeter portion 36 may form an
entire outer periphery 38 of sole assembly 14. In other
embodiments, perimeter portion 36 may form just a portion of outer
periphery 38. As illustrated here, perimeter portion 36 may also
completely surround an outer periphery 40 of core portion 32. As
illustrated here, inserts 34 may be completely surrounded by and
contained within core portion 32.
[0035] Preforms of the components of sole assembly 14 are seen in
exploded form in FIG. 3. As seen here, core portion preform 32'
includes ribs 42 that extend downwardly from its lower surface 44,
and define a plurality of interior recesses 46. Each insert preform
34' is configured to be seated or received in one of interior
recesses 46. Ribs 42 also define a shoulder 48 extending about at
least a portion of core portion preform 32'.
[0036] An aperture 50 extending through perimeter portion preform
36' defines an interior lip 52 that is seated on shoulder 48 of
core portion preform 32'. As seen in FIG. 2, in the finished
product of sole assembly 14, the surface of aperture 50 abuts the
exterior perimeter of ribs 42.
[0037] As seen here in FIG. 3, surface irregularities 53 may be
formed in the lower surfaces of core portion preform 32', insert
preforms 34', and perimeter portion preform 36'. Surface
irregularities 53 may take any desired form. In the illustrated
embodiment, surface irregularities 53 include a plurality of
grooves 55 and lugs or projections 57, which form a grid of
hexagonal projections 57 with corresponding grooves 55 surrounding
the projections, as seen more clearly in sole assembly 14 in FIG.
2. Surface irregularities 53 may serve aesthetic as well as
performance purposes.
[0038] A method of forming sole assembly 14 that reduces bleeding
between the colors of core portion preform 32', insert preforms
34', and perimeter portion preform 36' will now be described. As
seen in FIG. 4, a first preform mold assembly 54, which is used to
form core portion preform 32', includes an upper plate 56 and a
lower plate 58. Upper plate 56 and lower plate 58 may be rotatably
secured to one another with a hinge 60. A projection 61 extending
downwardly from upper plate 56 and a lower recess 62 formed in
lower plate 58 cooperate to define a core recess 63. As seen here,
first preform mold assembly 54 includes two core recesses 63 in
order to simultaneously form core portion preforms 32' for both
left and right sole assemblies.
[0039] Recesses 64 formed in the bottom of core recess 63 serve to
form ribs 42 when core portion preform 32' is formed in first
preform mold assembly 54. Recesses 64 may include surface
irregularities 66, which serve to form the mating surface
irregularities 53 in the lower surface of ribs 42, as described
above in conjunction with FIG. 2.
[0040] Core portion preform 32' is formed in core recess 63 of
first preform mold assembly 54 in known fashion, with heated EVA
being inserted into core recess 63. The resultant EVA core portion
preform 32' is later combined with insert preforms 34' and
perimeter preform 36' to form sole assembly 14, as described in
greater detail below.
[0041] A second preform mold assembly 68, seen in FIG. 5, is used
to form insert preforms 34' and perimeter portion preform 36'.
Second preform mold assembly 68 includes a bottom plate 70, a top
plate 72, a core plate 73 positioned below top plate 72, and a
sidewall plate 74 positioned between bottom plate 70 and core plate
73. The plates of second preform mold assembly 68 are connected by
way of a hinge 76. A projection 78 extending downwardly from core
plate 73, an aperture 80 extending through sidewall plate 74, and a
recess 82 formed in the top surface of bottom plate 70 cooperate to
define first, or insert, recesses 84 and a second, or perimeter,
recess 86, seen in FIGS. 6 and 7. As seen here, second preform mold
assembly 68 includes two sets of insert recesses 84 and two
perimeter recesses 63 in order to simultaneously form of insert
preforms 34' and perimeter portion preforms 36' for both left and
right sole assemblies.
[0042] Surface irregularities 88 formed in the bottom surface of
recess 82 serve to form the mating surface irregularities 53 in the
lower surface of inserts 34 and perimeter portion 36, as described
above with respect to core portion 32 and in conjunction with FIG.
2.
[0043] A perimeter portion preform 36' with insert preforms 34'
seated therein and formed in second preform mold assembly 68 is
shown here for illustrative purposes in the right recess 82 of
bottom plate 70. It is to be appreciated that any number of insert
preforms 34' may be formed in second preform mold assembly 68. In
the illustrated embodiment, there are three insert preforms 34'
used to form sole assembly 14. It is to be appreciated that a
single insert preform 34', or any number of insert preforms 34',
may be used to form sole assembly 14.
[0044] As seen in FIG. 6, sidewall plate 74 and core plate 73 are
pivoted downwardly into a closed position onto bottom plate 70. The
heated EVA for forming perimeter portion preform 36' is then
injected through a first gate 90 formed in core plate 73, as
illustrated with arrow A. The EVA for perimeter portion preform 36'
is thus positioned within perimeter recess 63.
[0045] After heated EVA is injected into perimeter recess 63, top
plate 72 is then pivoted down into a closed position on core plate
73. Heated EVA for forming insert portions 34' is then injected
through a second gate 92 formed in top plate 72 and core plate 73
into insert recesses 84. Thus, the configuration of the second
preform mold assembly 68 allows for the simultaneous formation of
two different colors of the injected EVA material to form both
insert preforms 34' and perimeter portion preform 36'.
[0046] All of the preforms, that is, core portion preform 32',
insert preforms 34', and perimeter portion preform 36', each having
a different color, are then preassembled into a single sole
assembly preform 94. As illustrated in FIGS. 8-10, this unitary
sole assembly preform 94, formed of all three colored materials is
then placed in a single step into a recess 96 formed in a heated
bottom plate 98 of a third mold assembly 100, as depicted by arrow
C. Once sole assembly preform 94 is seated in recess 96, a top
plate 102 of third mold assembly 100 is positioned on bottom plate
98 so as to close third mold assembly 100. Sole assembly preform 94
is then subjected to heat within third mold assembly 100 for a
predetermined time period so that core portion preform 32', insert
preforms 34', and perimeter portion preform 36' bond to one
another, thereby forming sole assembly 14.
[0047] In certain embodiments, third mold assembly 100 is
maintained at a temperature between approximately 170.degree. C.
and 180.degree. C. for approximately 10 minutes. The specific
temperature and time period used to form sole assembly 14 in third
mold assembly 100 can be varied, in known fashion, depending on the
particular EVA used.
[0048] In known fashion, after sole assembly 14 is removed from
third mold assembly 100, sole assembly 14 will expand. Sole
assembly 14 then goes through typical stabilization steps,
including cooling and trimming, as necessary.
[0049] By inserting the entire unitary preform 94 into recess 96 at
one time, bleeding between the different colors of the portions of
preform 94 as sole assembly 14 is formed is reduced, since all of
the materials start melting at the same time upon insertion into
third mold assembly 100.
[0050] In certain embodiments, as seen in FIG. 2 and noted above,
the surface irregularities 53 may form a defined pattern. As seen
in the embodiment illustrated here, surface irregularities 53 form
a grid of hexagonal projections 57 with corresponding grooves 55
formed about projections 57. In such an embodiment, it may be
desirable to have the boundaries between the different colors, that
is, the color lines between core portion 32, inserts 34, and
perimeter portion 36 not match or follow exactly along the edges of
projections 57 or grooves 55. Any bleeding between the different
colors will be more observable if the color lines are attempted to
line up with the edges of projections 57 and grooves 55. The user's
eye will be less likely drawn to the bleeding if the color lines
move across projections 57, rather than exclusively along the
perimeters of projections 57.
[0051] Thus, while there have been shown, described, and pointed
out fundamental novel features of various embodiments, it will be
understood that various omissions, substitutions, and changes in
the form and details of the devices illustrated, and in their
operation, may be made by those skilled in the art without
departing from the spirit and scope of the invention. For example,
it is expressly intended that all combinations of those elements
and/or steps which perform substantially the same function, in
substantially the same way, to achieve the same results are within
the scope of the invention. Substitutions of elements from one
described embodiment to another are also fully intended and
contemplated. It is the intention, therefore, to be limited only as
indicated by the scope of the claims appended hereto.
* * * * *