U.S. patent application number 15/570797 was filed with the patent office on 2018-05-03 for footwear sole structure including a spring plate.
This patent application is currently assigned to NIKE, Inc.. The applicant listed for this patent is NIKE, Inc.. Invention is credited to Geng Luo, Jay T. Worobets.
Application Number | 20180116335 15/570797 |
Document ID | / |
Family ID | 55967463 |
Filed Date | 2018-05-03 |
United States Patent
Application |
20180116335 |
Kind Code |
A1 |
Worobets; Jay T. ; et
al. |
May 3, 2018 |
Footwear Sole Structure Including a Spring Plate
Abstract
An article of footwear may include an upper, an outsole, and a
spring plate. The spring plate may be located above at least a
portion of the outsole and may extend through at least medial
forefoot and medial midfoot regions. The spring plate may have an
unloaded shape in which a front portion of the spring plate in a
forefoot region is downwardly bent relative to a rear portion of
the spring plate located rearward of the front portion. The spring
plate may comprise an open central region defined by a surrounding
band and may be nondestructively removable from and replaceable
into the upper. The article may further include at least one inner
sole member shaped to rest securely within a void defined at least
in part by the upper. The at least one inner sole member may be
compressible in at least first and fifth metatarsophalangeal joint
regions.
Inventors: |
Worobets; Jay T.; (Portland,
OR) ; Luo; Geng; (Portland, OR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
NIKE, Inc. |
Beaverton |
OR |
US |
|
|
Assignee: |
NIKE, Inc.
Beaverton
OR
|
Family ID: |
55967463 |
Appl. No.: |
15/570797 |
Filed: |
May 4, 2016 |
PCT Filed: |
May 4, 2016 |
PCT NO: |
PCT/US16/30759 |
371 Date: |
October 31, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62156644 |
May 4, 2015 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A43B 7/141 20130101;
A43B 13/141 20130101; A43C 15/02 20130101; A43B 13/04 20130101;
A43B 13/223 20130101; A43B 13/12 20130101; A43B 7/1425 20130101;
A43B 23/027 20130101; A43B 7/1445 20130101; A43B 13/125 20130101;
A43B 13/146 20130101; A43B 13/26 20130101; A43B 13/122 20130101;
A43B 13/026 20130101; A43B 7/1435 20130101; A43B 13/10 20130101;
A43C 15/005 20130101; A43B 13/181 20130101; A43B 13/187
20130101 |
International
Class: |
A43B 13/14 20060101
A43B013/14; A43B 13/12 20060101 A43B013/12; A43B 13/04 20060101
A43B013/04; A43B 13/22 20060101 A43B013/22; A43B 13/18 20060101
A43B013/18; A43B 13/02 20060101 A43B013/02; A43B 23/02 20060101
A43B023/02; A43B 7/14 20060101 A43B007/14 |
Claims
1. An article of footwear comprising; an upper; an outsole; at
least one inner sole member shaped to rest securely within a void
defined at least in part by the upper, wherein a portion of the
void above a top surface of the at least one inner sole member is
sized to accommodate a wearer foot, and wherein the at least one
inner sole member is compressible in at least first and fifth
metatarsophalangeal joint regions; and a spring plate positioned
between at least a portion of the at least one inner sole member
and at least a portion of the outsole, the spring plate extending
through at least medial forefoot and medial midfoot regions and
having an unloaded shape in which a front portion of the spring
plate in the forefoot region is downwardly bent relative to a rear
portion of the spring plate located rearward of the front
portion.
2. The article of footwear of claim 1, wherein the spring plate
comprises an open region defined by a surrounding band.
3. The article of footwear of claim 2, wherein the surrounding band
is continuous around an entire periphery of the spring plate.
4. The article of footwear according to claim 1, wherein the front
portion of the spring plate is substantially flat and the rear
portion of the spring plate is substantially flat.
5. The article of footwear of claim 4, wherein the front portion of
the spring plate is downwardly bent relative to the rear portion of
the spring plate at an angle of about 20 degrees.
6. The article of footwear of claim 1, wherein the spring plate
extends substantially an entire length and width of the article
within the upper.
7. The article of footwear of claim 1, wherein the spring plate and
the at least one inner sole member are each nondestructively
removable from and replaceable into the upper.
8. The article of footwear of claim 1, wherein the spring plate is
nondestructively removable from and replaceable into the upper.
9. The article of footwear of claim 1, wherein the at least one
inner sole member has an unloaded shape in which a front portion of
the at least one inner sole member in the forefoot region is
downwardly bent relative to a rear portion of the at least one
inner sole member located rearward of the front portion of the at
least one inner sole member.
10. The article of footwear of claim 1, wherein a peripheral edge
of the spring plate has a shape that is generally the same as a
shape of a peripheral edge of the at least one inner sole
member.
11. The article of footwear of claim 1, wherein the spring plate is
positioned between a midsole and the outsole.
12. The article of footwear of claim 11, wherein the midsole is
external to the upper, wherein the spring plate is attached to a
bottom side of the midsole and a top side of the outsole, and
wherein a portion of the spring plate is exposed on a bottom of the
article.
13. An article of footwear comprising; an upper; an outsole; and a
spring plate positioned above at least a portion of the outsole,
the spring plate extending through at least medial forefoot and
medial midfoot regions and having an unloaded shape in which a
front portion of the spring plate in the forefoot region is
downwardly bent relative to a rear portion of the spring plate
located rearward of the front portion, the spring plate comprising
an open region defined by a surrounding band.
14. The article of footwear of claim 13, wherein the surrounding
band is continuous around an entire periphery of the spring
plate.
15. The article of footwear of claim 13, wherein the front portion
of the spring plate is substantially flat and the rear portion of
the spring plate is substantially flat.
16. The article of footwear of claim 15, wherein the front portion
of the spring plate is downwardly bent relative to the rear portion
of the spring plate at an angle between about 10 degrees and about
25 degrees.
17. The article of footwear of claim 13, wherein the spring plate
extends substantially an entire length and width of the article
within the upper.
18. (canceled)
19. The article of footwear of claim 13, further comprising at
least one inner sole member shaped to rest securely within a void
defined at least in part by the upper, wherein a portion of the
void above a top surface of the at least one inner sole member is
sized to accommodate a wearer foot, and wherein the at least one
inner sole member is compressible in at least first and fifth
metatarsophalangeal joint regions.
20. An article of footwear comprising; an upper; an outsole; and a
spring plate positioned above at least a portion of the outsole,
the spring plate extending through at least medial forefoot and
medial midfoot regions and having an unloaded shape in which a
front portion of the spring plate in the forefoot region is
downwardly bent relative to a rear portion of the spring plate
located rearward of the front portion, the spring plate being
nondestructively removable from and replaceable into the upper.
21. The article of footwear of claim 20, wherein the spring plate
comprises an open region defined by a surrounding band.
22. The article of footwear of claim 21, wherein the surrounding
band is continuous around an entire periphery of the spring
plate.
23. The article of footwear of claim 20, wherein the spring plate
extends substantially an entire length and width of the article
within the upper.
24. The article of footwear of claim 20, further comprising at
least one inner sole member shaped to rest securely within the
void, wherein a portion of the void above a top surface of the at
least one inner sole member is sized to accommodate a wearer foot,
and wherein the at least one inner sole member is compressible in
at least first and fifth metatarsophalangeal joint regions.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to U.S. provisional patent
application No. 62/156,644, titled "Footwear Sole Structure
Including a Spring Plate" and filed May 4, 2015. Application No.
62/156,644, in its entirety, is incorporated by reference
herein.
BACKGROUND
[0002] Conventional articles of footwear generally include an upper
and a sole structure. The upper provides a covering for the foot
and securely positions the foot relative to the sole structure. The
sole structure is secured to a lower portion of the upper and is
configured so as to be positioned between the foot and the ground
when a wearer is standing, walking or running.
[0003] As a result of ground contact during walking and running,
the metatarsophalangeal joints in a person's foot undergo an
extension controlled by the joint flexor muscle-tendon units.
Associated with this controlled extension is mechanical energy
expenditure at the joint. In conventional footwear, little to none
of this mechanical energy is recovered to contribute back to
ongoing movement. Reducing this energy expenditure and/or improving
the energy recovery can potentially improve locomotion efficiency
and elicit a new sensation to a person who is walking or running.
There have been previous efforts to include features in sole
structures to help improve energy recovery at the
metatarsophalangeal joint. However, known attempts in this regard
have not addressed certain problems and/or have otherwise left
substantial room for improvement.
SUMMARY
[0004] This Summary is provided to introduce a selection of
concepts in a simplified form that are further described below in
the Detailed Description. This Summary is not intended to identify
key features or essential features of the invention.
[0005] In some embodiments, an article of footwear may include an
upper, an outsole, an inner sole member, and a spring plate. The
inner sole member may be shaped to rest securely within a void
defined at least in part by the upper. A portion of the void above
a top surface of the inner sole member may be sized to accommodate
a wearer foot. The inner sole member may be compressible in at
least first and fifth metatarsophalangeal joint regions. The spring
plate may be positioned between at least a portion of the inner
sole member and at least a portion of the outsole. The spring plate
may extend through at least medial forefoot and medial midfoot
regions and may have an unloaded shape in which a front portion of
the spring plate in the forefoot region is downwardly bent relative
to a rear portion of the spring plate located rearward of the front
portion.
[0006] In some embodiments, an article of footwear may include an
upper, an outsole, and a spring plate. The spring plate may be
positioned above at least a portion of the outsole. The spring
plate may extend through at least medial forefoot and medial
midfoot regions and may have an unloaded shape in which a front
portion of the spring plate in the forefoot region is downwardly
bent relative to a rear portion of the spring plate located
rearward of the front portion. The spring plate may comprise an
open region defined by a surrounding band.
[0007] In some embodiments, an article of footwear may include an
upper, an outsole, and a spring plate positioned above at least a
portion of the outsole. The spring plate may extend through at
least medial forefoot and medial midfoot regions and may have an
unloaded shape in which a front portion of the spring plate in the
forefoot region is downwardly bent relative to a rear portion of
the spring plate located rearward of the front portion. The spring
plate may be nondestructively removable from and replaceable into
the upper.
[0008] Additional embodiments are described herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Some embodiments are illustrated by way of example, and not
by way of limitation, in the figures of the accompanying drawings
and in which like reference numerals refer to similar elements.
[0010] FIG. 1A is a diagram showing bones in a human right foot
from a top (dorsal) view.
[0011] FIG. 1B is a diagram showing bones of a human right foot
from a medial side view.
[0012] FIG. 2 is a medial side view of a shoe according to some
embodiments.
[0013] FIG. 3 is a partially schematic cross-sectional diagram
showing the internal components of the shoe of FIG. 2, together
with a wearer foot.
[0014] FIG. 4A is a medial side view of the spring plate from the
shoe of FIG. 2.
[0015] FIGS. 4B through 4F are respective top, front, lateral side,
bottom, and rear views of the spring plate from the shoe of FIG.
2.
[0016] FIGS. 4G and 4H are respective front medial perspective and
rear medial perspective views of the spring plate from the shoe of
FIG. 2.
[0017] FIG. 5 is a partially schematic medial side view of a spring
plate similar to FIG. 4A.
[0018] FIG. 6 is a lateral side view of a shoe according to some
additional embodiments.
[0019] FIG. 7 is a bottom view of the shoe of FIG. 6.
[0020] FIG. 8 is an exploded, partially schematic lateral side view
of the shoe of FIG. 6.
[0021] FIG. 9 is another bottom view of the shoe of FIG. 6.
[0022] FIGS. 10A through 10C are bottom views of a shoe according
to some further embodiments.
DETAILED DESCRIPTION
[0023] In at least some embodiments, an article of footwear may
include an upper, an outsole, and a spring plate. The spring plate
may be located above at least a portion of the outsole and may
extend through at least medial forefoot and medial midfoot regions.
The spring plate may have an unloaded shape in which a front
portion of the spring plate in a forefoot region is downwardly bent
relative to a rear portion of the spring plate located rearward of
the front portion. The spring plate may comprise an open central
region defined by a surrounding band and may be nondestructively
removable from and replaceable into the upper.
[0024] In at least some embodiments, an article of footwear may
include an upper, an outsole, and a spring plate. The article may
further include at least one inner sole member shaped to rest
securely within a void defined at least in part by the upper. A
portion of the void above a top surface of the at least one inner
sole member may be sized to accommodate a wearer foot, and the at
least one inner sole member may be compressible in at least first
and fifth metatarsophalangeal joint regions.
[0025] Additional embodiments are described herein.
[0026] To assist and clarify subsequent description of various
embodiments, various terms are defined herein. Unless context
indicates otherwise, the following definitions apply throughout
this specification (including the example embodiments included in
the list of example embodiments attached hereto). "Shoe" and
"article of footwear" are used interchangeably to refer to an
article intended for wear on a human foot. A shoe may or may not
enclose the entire foot of a wearer. For example, a shoe could
include a sandal or other article that exposes large portions of a
wearing foot. The "interior" of a shoe refers to space that is
occupied by a wearer's foot when the shoe is worn. An interior
side, surface, face, or other aspect of a shoe component refers to
a side, surface, face, or other aspect of that component that is
(or will be) oriented toward the shoe interior in a completed shoe.
An exterior side, surface, face, or other aspect of a component
refers to a side, surface, face or other aspect of that component
that is (or will be) oriented away from the shoe interior in the
completed shoe. In some cases, the interior side, surface, face, or
other aspect of a component may have other elements between that
interior side, surface, face or other aspect and the interior in
the completed shoe. Similarly, an exterior side, surface, face or
other aspect of a component may have other elements between that
exterior side, surface, face or other aspect and the space external
to the completed shoe.
[0027] Shoe elements can be described based on regions and/or
anatomical structures of a human foot wearing that shoe, and by
assuming that the interior of the shoe generally conforms to and is
otherwise properly sized for the wearing foot. FIG. 1A shows
outlines of bones in a human right foot 1 from a dorsal, or top,
view. Those bones are the first distal phalanx 2, the first
proximal phalanx 3, the first metatarsal 4, the second distal
phalanx 5, the second middle phalanx 6, the second proximal phalanx
7, the second metatarsal 8, the third distal phalanx 9, the third
middle phalanx 10, the third proximal phalanx 11, the third
metatarsal 12, the fourth distal phalanx 13, the fourth middle
phalanx 14, the fourth proximal phalanx 15, the fourth metatarsal
16, the fifth distal phalanx 17, the fifth middle phalanx 18, the
fifth proximal phalanx 19, the fifth metatarsal 20, the medial
cuneiform 21, the intermediate cuneiform 22, the lateral cuneiform
23, the navicular 24, the cuboid 25, the talus 26, and the
calcaneus 27. FIG. 1B is a medial side view of bones in foot 1.
Also shown in FIG. 1B are portions of the two lower leg bones: the
tibia 28 and the fibula 29. These lower leg bones are movably
attached to the talus 26. The exact shape and size of the bones in
a foot will vary from individual to individual, and FIGS. 1A and 1B
are merely intended as convenient general references.
[0028] A forefoot region of a foot includes the heads and bodies of
the metatarsals 4, 8, 12, 16, and 20, as well as the phalanges 2,
3, 5-7, 9-11, 13-15, and 17-19. A forefoot element of a shoe is an
element having one or more portions located under, over, to the
lateral and/or medial side of, and/or in front of a wearer's
forefoot (or portion thereof) when the shoe is worn. A midfoot
region of a foot includes the cuboid 25, navicular 24, and
cuneiforms 21-23, as well as the bases of the metatarsals 4, 8, 12,
16, and 20. A midfoot element of a shoe is an element having one or
more portions located under, over, and/or to the lateral and/or
medial side of a wearer's midfoot (or portion thereof) when the
shoe is worn. A hindfoot (or heel) region of a foot includes the
talus 26 and calcaneus 27. A hindfoot (or heel) element of a shoe
is an element having one or more portions located under, to the
lateral and/or medial side of, and/or behind a wearer's hindfoot
(or portion thereof) when the shoe is worn. The forefoot region may
overlap with the midfoot region, as may the midfoot and hindfoot
regions.
[0029] Unless indicated otherwise, a longitudinal axis refers to a
horizontal heel-toe axis along the center of the foot that is
roughly parallel to a line along the second metatarsal and second
phalanges. A transverse axis refers to a horizontal axis across the
foot that is generally perpendicular to a longitudinal axis. A
longitudinal direction is generally parallel to a longitudinal
axis. A transverse direction is generally parallel to a transverse
axis.
[0030] The metatarsophalangeal joints of a human foot are the
joints between the metatarsal heads and the proximal phalanges. A
first metatarsophalangeal joint 31 connects the first proximal
phalanx 3 and the head of first metatarsal 4. A second
metatarsophalangeal joint 32 connects the second proximal phalanx 7
and the head of second metatarsal 8. A third metatarsophalangeal
joint 33 connects the third proximal phalanx 11 and the head of
third metatarsal 12. A fourth metatarsophalangeal joint 34 connects
the fourth proximal phalanx 15 and the head of fourth metatarsal
16. A fifth metatarsophalangeal joint 35 connects the fifth
proximal phalanx 19 and the head of fifth metatarsal 20.
[0031] The metatarsophalangeal joints allow the toes to flex, i.e.,
to curl downward towards the bottom of the foot. The
metatarsophalangeal joints also allow the toes to extend, i.e.,
bend upward toward the top of the foot. This is indicated in FIG.
1B, a medial side view of bones in foot 1. Phalanx 3 of the foot 1
big toe rotates upward about the head of first metatarsal 4 during
extension, and rotates downward about the head of first metatarsal
4 during flexion. The other toes rotate about their corresponding
metatarsal heads at the other metatarsophalangeal joints 32-35.
[0032] As is generally known in the art, the second half of the
stance phase is the portion of the gait cycle during which the leg
moves from a flat footed position to a lifted heel position, and
continues through pushing off with the toes. Throughout the second
half of the stance phase, the metatarsophalangeal joints undergo
extension as the foot rolls from heel to toe. To counteract the
extension moment caused by the external ground reaction force
during this foot roll, foot and lower leg muscles apply force to
create a flexion moment about the metatarsophalangeal joints. As a
result, negative joint mechanical work is performed as those
muscle-tendon units apply force to control extension. Only a small
portion of this energy is recovered at the very end of the foot
contact with the ground. In effect, the metatarsophalangeal joints
and their associated muscles act as energy absorbers that return
very little of the joint mechanical energy expended during the gait
cycle.
[0033] In at least some embodiments, an article of footwear
includes a downwardly bent spring plate that stores a large amount
of energy and returns energy during the second half of the stance
phase. This helps to change the metatarsophalangeal joints from
energy absorbers to spring-like joints. As weight is increasingly
shifted to the forefoot as the foot rolls forward, potential energy
from body mass is stored in the spring plate as the spring plate
changes from a bent to a more flat configuration. As the foot
continues to roll forward and the heel lifts off the ground, the
metatarsophalangeal joints begin to extend and additional energy is
stored as the spring plate bends further upward. By the time that
the runner nears the toe-off portion of the gait cycle, substantial
energy has been stored in the spring plate. This energy is released
back to the runner as the runner toes off at the end of the second
half of the stance phase.
[0034] FIG. 2 is a medial side view of a shoe 100 according to at
least some embodiments. The lateral side of shoe 100 has a similar
configuration and appearance, but is configured to correspond to a
lateral side of a wearer foot. Shoe 100 is configured for wear on a
right foot and is part of a pair that includes a shoe (not shown)
that is a mirror image of shoe 100 and is configured for wear on a
left foot.
[0035] Shoe 100 includes an upper 101 configured to surround and
retain the foot of a shoe 100 wearer. In the embodiment of shoe
100, upper 101 may comprise a textile panel 102 that has been knit
as a single element. In other embodiments, an upper may include
multiple panels and/or be formed from other materials and/or using
other manufacturing techniques. Although not visible in FIG. 2, a
lasting element (e.g., a Strobel) is stitched, bonded or otherwise
attached to the lower edge of panel 102 and generally extends the
entire length and width of upper 101. An interior face of the
lasting element and an interior face of panel 102 form a void of
shoe 100 that receives a wearer foot and other components described
below.
[0036] Panel 102 of upper 101 incorporates tensile elements 103.
Tensile elements 103 are shown with broken lines to indicate that
they may be incorporated into or otherwise contained within the
textile material of panel 102. Tensile elements 103 may be
substantially inextensible. With lace 104, tensile elements 103
help to hold the sole structure elements of shoe 100 in contact
with the wearer's foot. In particular, lower ends of elements 103
may be connected to the lasting element at the boundary between
that lasting element and the lower edge of panel 102. Upper ends of
elements 103 may terminate in loops 105 that form eyes for lace
104. Lace 104 may be cinched to tightly secure that lasting
element, together with sole and upper components attached thereto,
to the wearer foot. In some embodiments, upper 100 may lack a
tongue or an opening between eyelets 105 on medial and lateral
sides, although in other embodiments a conventional tongue and
tongue opening may be present. Upper 101 may optionally include a
bootie and/or other type of liner.
[0037] Upper 101 includes an ankle collar 110 that completely
surrounds a wearer foot at or above ankle level. An opening 111 in
ankle collar 110 allows a wearer to insert a foot into the interior
of shoe 100. Ankle collar 110 may include eyes or loops (not shown)
through which lace 104 passes. In this manner, cinching of lace 104
also secures ankle collar 110 about the wearer ankle. As explained
in more detail below, securing of ankle collar 110 in this manner
helps to hold hindfoot portions of the shoe 100 sole structure
against the wearer heel.
[0038] In some embodiments, upper 101 may be an upper as described
in U.S. patent application publication no. 2014/0137433, titled
"Footwear Upper Incorporating A Knitted Component With Collar And
Throat Portions" and incorporated by reference herein. In shoes
according to other embodiments, however, an upper may take other
forms.
[0039] The sole structure of shoe 100 includes an outsole 114, as
well as internal elements described below in connection with FIG.
3. Outsole 114 is highly flexible and may be formed from synthetic
rubber having a hardness and other properties similar to those of
synthetic rubber compounds conventionally used for footwear
outsoles. Outsole 114 may also include lugs or other external
elements to increase traction. As indicated above, upper 101
includes a lasting element that is attached to the lower edge of
panel 102. An exterior face of that lasting element is bonded
directly to outsole 114.
[0040] In some embodiments, outsole 114 may be an outsole such as
is described in U.S. patent application publication no.
2014/0150297, titled "Article of Footwear" and incorporated by
reference herein. In shoes according to other embodiments, however,
an outsole may take other forms.
[0041] FIG. 3 is a partially schematic cross-sectional diagram
showing internal components of shoe 100, as well as a wearer foot
1. In FIG. 3, upper 101 is shown in large broken lines and lasting
element 120 is shown in smaller broken lines. The void 121 of shoe
100 formed by upper 101 and lasting element 120 is sized to
accommodate foot 1, which shoe 100 is sized to fit, as well as
other components of the shoe 100 sole structure. Those additional
sole structure components include inner sole member 122 and spring
plate 123. FIG. 3 includes small gaps between inner sole member 122
and spring plate 123, between spring plate 123 and lasting element
120, and between lasting element 120 and outsole 114. These gaps
are only included for purposes of explanation so as to clearly
indicate different features. In an actual shoe such as shoe 100,
the bottom surface of inner sole member 122 may be in direct
contact with the top surface of spring plate 123, the bottom
surface of spring plate 123 may be in direct contact with the top
surface of lasting element 120, and the bottom surface of lasting
element 120 may be in direct contact with the top surface of
outsole 114.
[0042] Inner sole member 122 is configured to cushion and support
wearer foot 1. To provide support, a top surface of inner sole
member 122 may be generally contoured to conform to the plantar
surface of foot 1. Such contouring may include, e.g., a raised
medial midfoot portion to provide arch support. Inner sole member
122 is compressible in at least metatarsophalangeal joint regions
so as to cushion foot 1 during flattening of spring plate 123. To
provide cushioning, some or all of inner sole member 122 may be
formed from one or more closed cell polymer foams and/or other
type(s) compressible materials. Inner sole member 122 has a
peripheral shape that generally corresponds to that of a wearer
foot, and is sized to snugly fit within upper 101. In particular,
and when shoe 100 is assembled, the sides of inner sole member 122
are in contact with the inner surface of upper 101 (or of a liner
of upper 101, if a separate bootie or other liner is included).
[0043] In at least some embodiments, inner sole member 122 is a
removable foam midsole formed from ethylene vinyl acetate (EVA)
and/or other polymer foam material. In some embodiments, inner sole
member 122 may be formed from foam materials such as those used in
the LUNAR family of footwear products available from NIKE, Inc. of
Beaverton, Oreg. Additional examples of foam materials that can be
used for inner sole member 122 include materials described in U.S.
Pat. No. 7,941,938, which patent is incorporated by reference
herein, TPU (thermoplastic polyurethane) foams, and PU
(polyurethane) foams. In some embodiments, inner sole member 123 is
a removable foam midsole such as that described in U.S. patent
application publication no. 2014/0150297. In shoes according to
other embodiments, however, an inner sole member may take other
forms.
[0044] Inner sole member 122 is flexible and allows foot 1 to move
naturally. In particular, inner sole member 122 allows the toes of
foot 1 to flex and extend without imposing significant resistance.
One or more transverse sipes 124 may extend across inner sole
member 122 from the medial to the lateral side so as to allow
unrestricted toe extension. Additional sipes, not shown, may also
extend in transverse and longitudinal directions.
[0045] Spring plate 123 is situated between inner sole member 122
and lasting element 120. In the embodiment of shoe 1 and in at
least some other embodiments, spring plate 123 is also removable
and replaceable. FIG. 3 shows spring plate 123 in an unloaded
condition. In particular, the weight of the wearer has not been
placed on foot 1, and no flattening of spring plate 123 has
occurred. In the embodiment of shoe 100, spring plate 123 extends
the full length of shoe 100 and has an unloaded shape in which
forefoot portions of spring plate 123 are downwardly bent. As also
seen in FIG. 3, the contour of spring plate 123 is generally flat
in locations forward of the downward bend and in locations rearward
of the downward bend.
[0046] FIGS. 4A through 4H show spring plate 123 removed from shoe
100 and in an unloaded condition. FIG. 4A is a medial side view of
spring plate 123. FIG. 4B is a top view of spring plate 123. FIG.
4C is a front view of spring plate 123. FIG. 4D is a lateral side
view of spring plate 123. FIG. 4E is a bottom view of spring plate
123. FIG. 4F is a rear view of spring plate 123. FIG. 4G is a rear
perspective view of spring plate 123 from the medial side. FIG. 4H
is a front perspective view of spring plate 123 from the medial
side.
[0047] Spring plate 123 has a continuous band 131 that defines an
open center region 132. In some embodiments, and as discussed more
fully below, band 131 may be formed from an epoxy and carbon fiber
composite material. A peripheral edge of band 131 has a shape
generally corresponding to that of the lower part of void 121 and
to the bottom surface of inner sole member 122. The peripheral edge
of band 131 is sized so as to contact upper 101 (and/or a bootie or
other liner, if present) and/or lasting element 120, and so as not
to significantly shift in longitudinal or transverse directions
when shoe 100 is assembled. Spring plate 123 extends from a
rear-most end 133 to a forward-most end 134. Band 131 has a top
surface 135 and a bottom surface 136. When shoe 100 is assembled,
top surface 135 contacts the bottom surface of inner sole member
122 and bottom surface 136 contacts the top surface of lasting
element 120.
[0048] In the embodiment of spring plate 123, and for a male size
10 shoe, spring plate 123 has an overall width W of approximately
98 millimeters and an overall length L of approximately 275
millimeters. In that embodiment, width w of band 131 varies from
approximately 20 millimeters in hindfoot regions, to approximately
23 millimeters in forward midfoot and rear forefoot regions, to
approximately 30 millimeters at front-most end 134. These values
are only examples, however, and spring plates according to other
embodiments may have overall lengths, overall widths, and/or band
widths of different values. Band 131 has a thickness t that is
generally constant over all of band 131. As explained in more
detail below, values for thickness t may vary based on a target
wearer body mass and on materials used for spring plate 131.
[0049] As indicated above, a portion 139 of spring plate 123 in the
forefoot region bends downward in when spring plate 123 is in an
unloaded condition. The downward bend begins at an apex location
137 on the medial side and at an apex location 138 on the lateral
side and has an unloaded bend angle .alpha.. In the embodiment of
spring plate 123, a has a value of about 20.degree.. As used
herein, "about" means.+-.5%, with "about 20.degree." meaning
20.degree..+-.1.degree. (or between 19.degree. and 21.degree.).
This value is only an example, however, and spring plates according
to other embodiments may have bend angles of different values. In
some embodiments, an unloaded bend angle may be about 10.degree.,
about 11.degree., about 12.degree., about 13.degree., about
14.degree., about 15.degree., about 16.degree., about 17.degree.,
about 18.degree., about 19.degree., about 21.degree., about
22.degree., about 23.degree., about 24.degree., or about
25.degree..
[0050] A bend need not be constant. For example, portion 139 could
be curved, with a bend angle measured at a curve tangent increasing
toward front-most end 134. In such an embodiment, the bend angle
may increase from very small values near the apex locations to
larger values near the front-most end.
[0051] In at least some embodiments, spring plate 123 is fabricated
so as to have a desired stiffness for a particular range of wearer
body mass. In embodiments of spring plate 123 having approximate
dimensions as indicated above, and in which band 131 is fabricated
from an epoxy and carbon fiber composite, the number of carbon
fiber layups forming band 131 may be as shown in Table 1.
TABLE-US-00001 TABLE 1 Wearer Body Mass Carbon Fiber Target Range
(kg) Layup Layers 40-70 9 70-100 11-13 100-130 15-17
[0052] As seen in Table 1, a spring plate 123 for use in shoe 100
by heavier wearers will have more layers. Accordingly, a thickness
t for such a spring plate 123 may be greater than a thickness t of
a spring plate 123 intended for use in shoe 100 by less heavy
wearers. In some embodiments, a carbon fiber material used in layup
layers of a fabricated spring plate 123 may be a fabric having 3K
carbon warp yarn, 3K carbon weave yarn, a dry fabric weight of 204
GSM/6 oz., 2.times.2 twill weave style, a nominal construction warp
count of 13/in., and a nominal construction weave count of
13/in.
[0053] In some embodiments, a spring plate may have an angular
stiffness about the metatarsophalangeal joint axis in the range of
between 5 to 100 N*m/rad (Newton-meters per radian). These values
may correspond to bending moments about that axis that are required
to deflect a spring plate by 25.degree., which is the approximate
angular displacement that an athlete may achieve when running in a
shoe that includes a spring plate. This is illustrated in FIG. 5, a
partially schematic medial side view of spring plate 123 similar to
FIG. 4A. In FIG. 5, the metatarsophalangeal joint axis is aligned
with apexes 137 and 138. In some embodiments, apex 137 and/or apex
138 may be slightly in front of or behind the metatarsophalangeal
joint axis.
[0054] In some embodiments, shoe 100 and spring plate 123 may be
sold or otherwise provided separately. In this manner, a wearer can
choose a spring plate corresponding to his or her body mass. As
indicated above, spring plate 123 and inner sole member 122 may be
removable. Accordingly, a purchaser of shoe 100 could easily remove
inner sole member 122, remove a first spring plate 123, insert a
second spring plate 123 having a desired stiffness, and then
reinsert inner sole member 122.
[0055] In other embodiments, a spring plate may be formed from
other materials. Examples of such other materials include other
types of composites, e.g., epoxy-glass composites, polyester-carbon
composites, and polyester-glass composites. Additional examples of
such other materials include other polymers (with or without added
reinforcing material), metals, and combinations thereof.
[0056] The apex of the bend in spring plate 123 may be
approximately aligned with the metatarsophalangeal joints of the
foot of a shoe 100 wearer. Apex location 137 at which the downward
bend begins on the medial side may approximately correspond to the
portion of first metatarsal 4 just behind the head. Apex location
138 at which the downward bend begins on the lateral side may
approximately correspond to the portion of fifth metatarsal 20 just
behind the head. In some embodiments, however, an apex location may
be directly under a metatarsophalangeal joint or slightly in front
of a metatarsophalangeal joint. In some embodiments, one apex may
be under or slightly behind one metatarsophalangeal joint, with
another apex under or slightly in front of another
metatarsophalangeal joint.
[0057] In some embodiments, upper 101 and outsole 114 are
configured so as to provide minimal resistance to toe and forefoot
bending in either the flexion or extension directions. Outsole 114,
for example, may be relatively thin in the forefoot regions and/or
may comprise multiple transverse grooves similar to sipes 124 in
inner sole member 122. Upper 101 may also be relatively thin and/or
may include pleats, elastic regions, or other elements incorporated
into forefoot and midfoot regions to permit bending of upper 101.
In some embodiments, the combined bending resistance of the upper
and other sole structure elements is such that spring plate 123 can
deform the assembled shoe, when not worn, to conform to the
downward bend of spring plate 123.
[0058] When spring plate 123 is flattened as a shoe 100 wearer
rolls his or her foot 1 from the heel to the toe, the rear end of
spring plate 123 will push downward on the hindfoot region of
lasting element 120. If unrestrained, this would tend to pull the
hindfoot region of the shoe 100 sole structure away from the
wearer's heel. In some embodiments, hindfoot regions of upper 101
between ankle collar 110 and lasting element 120 may be relatively
inelastic so as to provide appropriate restraint. When ankle collar
120 is secured in place (e.g., by lace 104) and the wearer deforms
spring plate 123, the hindfoot portions of upper 101 will be placed
in tension between ankle collar 110 and lasting element 120. If
those portions of upper 101 are relatively inelastic, the hindfoot
portions of the shoe 100 sole structure are maintained in place
relative to the wearer's heel. In other embodiments, other
configurations may be used to hold a shoe sole structure against a
wearer heel during spring plate deformation. As but one example,
hindfoot region straps may be added to a shoe.
[0059] FIG. 6 is a lateral side view of a shoe 200 according some
additional embodiments. The medial side of shoe 200 has a similar
configuration and appearance, but is configured to correspond to a
lateral side of a wearer foot. Shoe 200 is configured for wear on a
right foot and is part of a pair that includes a shoe (not shown)
that is a mirror image of shoe 200 and is configured for wear on a
left foot.
[0060] Shoe 200 includes an upper 201 configured to surround and
retain the foot of a shoe 200 wearer. In the embodiment of shoe
200, upper 201 may be of conventional construction and include a
tongue 206 that spans a tongue opening 207 located in an instep
region. A lace 204, only certain segments of which are shown in
FIG. 6, may be used to cinch upper 201 about a wearer foot in a
conventional manner. A lasting element (e.g., a Strobel) may be
stitched, bonded or otherwise attached to the lower edge of upper
201 and generally extends the entire length and width of upper 201.
An interior face of the lasting element and an interior face of
upper 201 form a void of shoe 200 that receives a wearer foot
inserted through ankle opening 211.
[0061] The sole structure of shoe 200 includes a midsole 252, a
spring plate 223, a front outsole 214, and a rear outsole 215.
Midsole 252 and spring plate 223 are external relative to upper
201. As explained in detail below in connection with FIG. 8, the
sole structure of shoe 200 also includes an insole located within
the void of upper 201. Midsole 252 may be formed from one or more
compressible foam materials and may have a top surface that is
contoured, at least in part, to conform to a plantar region of a
wearer foot. Foam materials that may be used for midsole 252
include any of the foams that may be used to form inner sole member
122 of shoe 100.
[0062] FIG. 7 is a bottom view of shoe 200 and shows additional
details of outsoles 214 and 215. Front outsole 214 is approximately
U shaped and comprises a strip that extends around the outer edge
of spring plate 223 from a lateral midfoot region to a medial
midfoot region. An interior edge 261 of outsole 214 defines an open
region 262 exposing a portion of the bottom surface 236 of spring
plate 223. The lateral side of outsole 214 extends further rearward
than the medial side of outsole 214. A rounded end of the outsole
214 lateral side is spaced apart from a rounded end of the outsole
214 medial side to define a gap therebetween. A bottom surface of
front outsole 214 includes multiple pointed traction elements 256,
as well as four receptacles 260 configured to receive track spikes
258. Track spikes are omitted from the rear lateral and rear medial
receptacles 260 in FIGS. 6-8 for purposes of illustration. Front
outsole 214 may be molded from, e.g., hard rubber or other
conventional outsole materials, with receptacles 260 embedded at
the time of molding.
[0063] Rear outsole 215 covers a rear midfoot and heel region of
the lower surface of spring plate 223. Rear outsole 215 includes a
plurality of downwardly-extending traction elements 257. Rear
outsole 215 may also be molded from, e.g., hard rubber or other
conventional outsole materials.
[0064] FIG. 8 is an exploded, partially schematic lateral side view
of shoe 200. In FIG. 8, an outline of upper 201 is shown with a
first type of broken line and a lasting element 220 is shown with a
second type of broken line having smaller segments. Other
components of shoe 200 are shown in lateral side view.
[0065] As indicated above, and as shown schematically in FIG. 8,
lasting element 220 is joined to a bottom edge of upper 201 to
define a void of shoe 200. Located within that void is an inner
sole element in the form of insole 222. Insole 222 may be molded
from one or more compressible foam materials (e.g., foamed EVA,
foamed PU, blown rubber). In some embodiments, a top surface 241 of
insole 222 may include a fabric layer. Insole 222 may be molded to
have a curvature corresponding to the curvature of the undeformed
top surface of midsole 252. A bottom surface 242 of insole 222 may
rest against a top, interior face 243 of lasting element 220.
[0066] A bottom surface 244 of lasting element 220 may be bonded to
a top surface 245 of midsole 252. As indicated above, midsole 252
may be formed from one or more compressible foam materials. In some
embodiments, midsole 252 may be molded so that it has undeformed
contours similar to those indicated in FIG. 8. In particular, a
bottom surface 246 of midsole 252 may have a contour corresponding
to the contour of the top surface 235 of an undeformed spring plate
223. A top surface of midsole 252 may have a similar contour, but
with additional surface features to provide arch support, heel
elevation, etc.
[0067] Bottom surface 246 of midsole 252 may be bonded to top
surface 235 of spring plate 223. The bonding may be over all, or
over a sub-portion, of bottom surface 246 in contact with top
surface 235. Unlike spring plate 123, spring plate 223 lacks an
open region. However, spring plate 223 may otherwise be similar to
spring plate 123 with regard to thickness and other dimensions,
unloaded forefoot region bend angle .alpha., apex locations, etc.
Spring plate 223 may be formed from any of the materials described
above in connection with spring plate 123, may have layup details
and components similar to those described in connection with spring
plate 123, and/or may have angular stiffness characteristics
similar to those described in connection with FIG. 5. In the
embodiment of shoe 200, spring plate 223 has a slight upward bend
in the heel region. In other embodiments, however, a spring plate
otherwise similar to spring plate 223 in a shoe otherwise similar
to that of shoe 200 may be substantially flat in the heel region
(similar to spring plate 123).
[0068] Top surface 248 of front outsole 214 may be bonded to a
portion of spring plate 223 bottom surface 236 in the forefoot and
midfoot regions. The bonding may be over all, or over a
sub-portion, of top surface 248 in contact with bottom surface 236.
Top surface 249 of rear outsole 215 may be bonded to a portion of
spring plate 223 bottom surface 236 in the midfoot and heel
regions. The bonding may be over all, or over a sub-portion, of top
surface 249 in contact with bottom surface 236. A portion of
peripheral outer edge 271 rear outsole 215 may be substantially
coextensive with a portion of peripheral outer edge 272 of spring
plate 223. A portion of peripheral outer edge 273 front outsole 214
may be substantially coextensive with a portion of peripheral outer
edge 272 of spring plate 223. In some embodiments, edges may be
considered "substantially coextensive" if any offset between those
edges is less than 7 millimeters, less than 6 millimeters, less
than 5 millimeters, less than 4 millimeters, less than 3
millimeters, less than 2 millimeters, less than 1 millimeter, or
less than 0.5 less than 6 millimeter. In some embodiments, an
outsole (or multiple separate outsole elements) may cover all of a
spring plate bottom surface. In some such embodiments, some or all
of a peripheral edge of the spring plate may be substantially
coextensive with some or all of the peripheral edge(s) of the one
or more outsole elements covering the spring plate bottom
surface.
[0069] FIG. 9 is another bottom view of shoe 200, but with front
outsole 214 and rear outsole 215 omitted. As indicated above, and
as seen in seen in FIG. 9, spring plate 223 lacks an open region.
In particular, top surface 236 extends uninterrupted from medial to
lateral edges and from front end to rear end. Bottom surface 235
similarly extends uninterrupted from medial to lateral edges and
from front end to rear end. In the embodiment of shoe 200, spring
plate 223 covers the entire bottom surface 246 of midsole 252. In
other embodiments, a spring plate may cover less than all of a
midsole bottom surface.
[0070] In some embodiments, for example, a spring plate in a shoe
otherwise similar to shoe 200 may include an open region similar to
open region 132 of spring plate 123, or may include one or more
open regions having other configurations. Such open regions could
be included to, e.g., reduce weight and/or as a way of adjusting
spring force in the spring plate. Such open regions could also be
used to help position a spring plate relative to a midsole and/or
to help position one or more outsoles relative to the spring plate.
For example, FIG. 10A shows a bottom view of a shoe 300 that,
except as described below, is similar to shoe 200. A spring plate
and outsoles are omitted from FIG. 10A. As seen in FIG. 10A, bottom
surface 346 of midsole 352 includes a shelf 399 and a central
island 398 that extends downward (outward from shelf 399 in FIG.
10A). FIG. 10B is another bottom view of shoe 300 after a spring
plate 323 has been bonded to midsole 352. Spring plate 323 includes
an open region 332 similar to open region 132 of spring plate 123.
Open region 332 has a shape corresponding to the shape of island
398. Island 398 extends through open region 332, and bottom surface
336 of spring plate 323 is flush with the portion of the midsole
352 bottom surface 346 included in island 398. A top surface of
spring plate 323, not shown, is bonded to the portion of the
midsole 353 bottom surface 346 located in shelf 399. FIG. 10C is a
further bottom view of shoe 300 after bonding of outsole 314 and
315 to portions of the spring plate 323 bottom surface 336 and to
portions of the outsole 353 bottom surface 346 exposed through
opening 332. Outsoles 314 and 315 may be similar to outsoles 214
and 215, or may have other configurations.
[0071] Other embodiments include numerous additional variations on
the components and combinations described above. Without
limitation, such variations may include one or more of the
following. [0072] In some additional embodiments, a shoe may have a
sole structure similar to that of shoes 200 or 300, but may have an
upper similar to that of shoe 100. [0073] As indicated above, an
inner sole member such as insole 222 may be molded to have a
curvature such as is shown in FIG. 8. In some embodiments, an inner
sole member such as inner sole member 122 could be molded so as to
have an unloaded shape, similar to that shown in FIG. 3, in which a
forefoot region has a downward bend corresponding to a downward
bend of a spring plate that will be used with the inner sole
member. [0074] A spring plate may have a variable thickness t. For
example, a thickness t may be decreased in regions around a bend
apex so as to facilitate desired bendability, and increased in
regions where no less (or no) bendability is desired. [0075]
Parameters other than or in addition to number of layup layers may
be varied so as to achieve desired spring plate stiffness. For
example, a width of a band such as band 131 could be increased in a
bend apex region to increase stiffness, and vice versa. [0076]
Spring plate stiffness could be tuned so as to make the stiffness
at one of the medial or lateral side bend apexes greater than the
stiffness at the other of the medial or lateral side bend apexes.
Such tuning could be used, e.g., to help correct excessive
pronation or other undesirable characteristics of a wearer's gait.
[0077] An inner sole member could comprise more than one component.
For example, an inner sole member could comprise an inner midsole
and an separate sock liner. As another example, an inner sole
member could comprise a first inner midsole that rests within a
front portion of a shoe interior and a second inner midsole that
rests within a rear portion of the shoe interior, with the first
and second midsole overlapping in a middle portion of the shoe
interior. [0078] In the embodiment of shoe 100, no portion of inner
sole member 122 is below spring plate 123. In other embodiments,
one or more inner sole members or portions thereof might be located
under a spring plate. [0079] In some embodiments, a spring plate
might be incorporated into an inner sole member, into an outsole,
or into a midsole or other portion of a sole structure located
below a lasting element. A portion of a spring plate may be exposed
and form a portion of a ground contacting surface of a sole
structure. [0080] In some embodiments, an article of footwear may
include more than one spring plate. For example, a spring plate
similar to spring plate 123 may split into two separate spring
plates (e.g., a medial side spring plate and a lateral side spring
plate). As another example, spring plates may overlap one another.
Some or all of overlapping spring plates may not extend around an
entire periphery of the sole structure. [0081] A spring plate may
have different bend angles on medial and lateral sides. As but one
example, a bend angle on a medial side of a spring plate could be
greater than a bend angle on a lateral side of a spring plate.
[0082] A bend angle may be sharper (i.e., with a smaller bend
radius) or more gentle (i.e., with a larger bend radius) than is
shown in FIGS. 3, 4A, 4D, 4G, 4H, and 8. [0083] In some
embodiments, a spring plate that is nondestructively removable from
and replaceable into the void of an upper, similar to spring plate
123, may lack an open center region and may instead have top and
bottom surfaces that extend uninterrupted from medial to lateral
edges and from front end to rear end, similar to spring plate
223.
[0084] The foregoing description of embodiments has been presented
for purposes of illustration and description. The foregoing
description is not intended to be exhaustive or to limit
embodiments of the present invention to the precise form disclosed,
and modifications and variations are possible in light of the above
teachings or may be acquired from practice of various embodiments.
The embodiments discussed herein were chosen and described in order
to explain the principles and the nature of various embodiments and
their practical application to enable one skilled in the art to
utilize the present invention in various embodiments and with
various modifications as are suited to the particular use
contemplated. Any and all combinations, subcombinations and
permutations of features from herein-described embodiments are the
within the scope of the invention. In the claims, a reference to a
potential or intended wearer or a user of a component does not
require actual wearing or using of the component or the presence of
the wearer or user as part of the example embodiment.
[0085] For the avoidance of doubt, the present application
includes, without limitation, the subject-matter described in the
following numbered paragraphs (referred to as "para." or "paras."):
[0086] 1. An article of footwear comprising an upper; an outsole;
at least one inner sole member shaped to rest securely within a
void defined at least in part by the upper; and a spring plate
positioned between at least a portion of the at least one inner
sole member and at least a portion of the outsole, the spring plate
extending through at least medial forefoot and medial midfoot
regions and having an unloaded shape in which a front portion of
the spring plate in the forefoot region is downwardly bent relative
to a rear portion of the spring plate located rearward of the front
portion. [0087] 2. The article of footwear of para. 1, wherein a
portion of the void above a top surface of the at least one inner
sole member is sized to accommodate a wearer foot. [0088] 3. The
article of footwear of para. 1 or para. 2, wherein the at least one
inner sole member is compressible in at least first and fifth
metatarsophalangeal joint regions. [0089] 4. The article of
footwear of any of paras. 1 through 3, wherein the spring plate
comprises an open region defined by a surrounding band. [0090] 5.
The article of footwear of para. 4, wherein the surrounding band is
continuous around an entire periphery of the spring plate. [0091]
6. The article of footwear of any of paras. 1 through 5, wherein
the front portion of the spring plate is substantially flat and the
rear portion of the spring plate is substantially flat. [0092] 7.
The article of footwear of any of paras. 1 through 6, wherein the
spring plate extends substantially an entire length and width of
the article within the upper. [0093] 8. The article of footwear of
any of paras. 1 through 7, wherein the at least one inner sole
member has an unloaded shape in which a front portion of the at
least one inner sole member in the forefoot region is downwardly
bent relative to a rear portion of the at least one inner sole
member located rearward of the front portion of the at least one
inner sole member. [0094] 9. The article of footwear of any of
paras. 1 through 8, wherein a peripheral edge of the spring plate
has a shape that is generally the same as a shape of a peripheral
edge of the at least one inner sole member. [0095] 10. The article
of footwear of any of paras. 1 through 9, further comprising a
midsole, wherein a surface of the spring plate is at least
partially bonded to a surface of the midsole. [0096] 11. The
article of footwear of any of paras. 1 through 10, wherein a
surface of the spring plate is at least partially bonded to a
surface of the outsole. [0097] 12. The article of footwear of para.
11, wherein at least a portion of a peripheral edge of the outsole
is substantially coextensive with at least a portion of a
peripheral edge of the spring plate. [0098] 13. The article of
footwear of any of paras. 1 through 9, wherein the spring plate is
nondestructively removable from and replaceable into the upper.
[0099] 14. The article of footwear of any of paras. 1 through or
13, wherein the at least one inner sole member is nondestructively
removable from and replaceable into the upper. [0100] 15. The
article of footwear of any of paras. 1 through 14, wherein the
front portion of the spring plate is downwardly bent relative to
the rear portion of the spring plate at an angle between about 10
degrees and about 25 degrees. [0101] 16. The article of footwear of
any of paras. 1 through 15, wherein the front portion of the spring
plate is downwardly bent relative to the rear portion of the spring
plate at an angle of about 20 degrees. [0102] 17. The article of
footwear of any of paras. 1 through 15, wherein the front portion
of the spring plate is downwardly bent relative to the rear portion
of the spring plate at an angle of about 19 degrees. [0103] 18. The
article of footwear of any of paras. 1 through 15, wherein the
front portion of the spring plate is downwardly bent relative to
the rear portion of the spring plate at an angle of about 18
degrees. [0104] 19. The article of footwear of any of paras. 1
through 15, wherein the front portion of the spring plate is
downwardly bent relative to the rear portion of the spring plate at
an angle of about 17 degrees. [0105] 20. The article of footwear of
any of paras. 1 through 15, wherein the front portion of the spring
plate is downwardly bent relative to the rear portion of the spring
plate at an angle of about 16 degrees. [0106] 21. The article of
footwear of any of paras. 1 through 15, wherein the front portion
of the spring plate is downwardly bent relative to the rear portion
of the spring plate at an angle of about 15 degrees. [0107] 22. The
article of footwear of any of paras. 1 through 15, wherein the
front portion of the spring plate is downwardly bent relative to
the rear portion of the spring plate at an angle of about 10
degrees. [0108] 23. The article of footwear of any of paras. 1
through 15, wherein the front portion of the spring plate is
downwardly bent relative to the rear portion of the spring plate at
an angle of about 21 degrees. [0109] 24. The article of footwear of
any of paras. 1 through 15, wherein the front portion of the spring
plate is downwardly bent relative to the rear portion of the spring
plate at an angle of about 22 degrees. [0110] 25. The article of
footwear of any of paras. 1 through 15, wherein the front portion
of the spring plate is downwardly bent relative to the rear portion
of the spring plate at an angle of about 23 degrees. [0111] 26. The
article of footwear of any of paras. 1 through 15, wherein the
front portion of the spring plate is downwardly bent relative to
the rear portion of the spring plate at an angle of about 24
degrees. [0112] 27. The article of footwear of any of paras. 1
through 15, wherein the front portion of the spring plate is
downwardly bent relative to the rear portion of the spring plate at
an angle of about 25 degrees. [0113] 28. An article of footwear
comprising an upper; an outsole; and a spring plate positioned
above at least a portion of the outsole, the spring plate extending
through at least medial forefoot and medial midfoot regions and
having an unloaded shape in which a front portion of the spring
plate in the forefoot region is downwardly bent relative to a rear
portion of the spring plate located rearward of the front portion,
the spring plate comprising an open region defined by a surrounding
band. [0114] 29. The article of footwear of para. 28, wherein the
surrounding band is continuous around an entire periphery of the
spring plate. [0115] 30. The article of footwear of para. 28 or
para. 29, wherein the front portion of the spring plate is
substantially flat and the rear portion of the spring plate is
substantially flat. [0116] 31. The article of footwear of any of
paras. 28 through 30, wherein the spring plate extends
substantially an entire length and width of the article within the
upper. [0117] 32. The article of footwear of any of paras. 28
through 31, further comprising at least one inner sole member
shaped to rest securely within a void defined at least in part by
the upper. [0118] 33. The article of footwear of para. 32, wherein
a portion of the void above a top surface of the at least one inner
sole member is sized to accommodate a wearer foot. [0119] 34. The
article of footwear of para. 32 or para. 33, wherein the at least
one inner sole member is compressible in at least first and fifth
metatarsophalangeal joint regions. [0120] 35. The article of
footwear of any of paras. 28 through 34, further comprising a
midsole, wherein a surface of the spring plate is at least
partially bonded to a surface of the midsole. [0121] 36. The
article of footwear of any of paras. 28 through 35, wherein a
surface of the spring plate is at least partially bonded to a
surface of the outsole. [0122] 37. The article of footwear of para.
36, wherein at least a portion of a peripheral edge of the outsole
is substantially coextensive with at least a portion of a
peripheral edge of the spring plate. [0123] 38. The article of
footwear of any of paras. 28 through 34, wherein the spring plate
is nondestructively removable from and replaceable into the upper.
[0124] 39. The article of footwear of any of paras. 28 through 38,
wherein the front portion of the spring plate is downwardly bent
relative to the rear portion of the spring plate at an angle
between about 10 degrees and about 25 degrees. [0125] 40. The
article of footwear of any of paras. 28 through 39, wherein the
front portion of the spring plate is downwardly bent relative to
the rear portion of the spring plate at an angle of about 20
degrees. [0126] 41. An article of footwear comprising an upper; an
outsole; and a spring plate positioned above at least a portion of
the outsole, the spring plate extending through at least medial
forefoot and medial midfoot regions and having an unloaded shape in
which a front portion of the spring plate in the forefoot region is
downwardly bent relative to a rear portion of the spring plate
located rearward of the front portion, the spring plate being
nondestructively removable from and replaceable into the upper.
[0127] 42. The article of footwear of para. 41, wherein the spring
plate comprises an open region defined by a surrounding band.
[0128] 43. The article of footwear of para. 41 or para. 42, wherein
the surrounding band is continuous around an entire periphery of
the spring plate. [0129] 44. The article of footwear of any of
paras. 41 through 43, wherein the front portion of the spring plate
is substantially flat and the rear portion of the spring plate is
substantially flat. [0130] 45. The article of footwear of any of
paras. 41 through 44, wherein the spring plate extends
substantially an entire length and width of the article within the
upper. [0131] 46. The article of footwear of any of paras. 41
through 45, further comprising at least one inner sole member
shaped to rest securely within the void. [0132] 47. The article of
footwear of para. 46, wherein a portion of the void above a top
surface of the at least one inner sole member is sized to
accommodate a wearer foot. [0133] 48. The article of footwear of
para. 46 or para. 47, wherein the at least one inner sole member is
compressible in at least first and fifth metatarsophalangeal joint
regions. [0134] 49. The article of footwear of any of paras. 41
through 48, wherein the front portion of the spring plate is
downwardly bent relative to the rear portion of the spring plate at
an angle between about 10 degrees and about 25 degrees. [0135] 50.
An article of footwear comprising an upper; a midsole engaged with
the upper, a spring plate engaged with a bottom of the midsole, and
an outsole engaged with a bottom of the spring plate. [0136] 51.
The article of footwear of para. 50, further comprising a midsole,
wherein a surface of the spring plate is at least partially bonded
to a surface of the midsole. [0137] 52. The article of footwear of
para. 50 or para. 51, wherein a surface of the spring plate is at
least partially bonded to a surface of the outsole. [0138] 53. The
article of footwear of para. 52, wherein at least a portion of a
peripheral edge of the outsole is substantially coextensive with at
least a portion of a peripheral edge of the spring plate. [0139]
54. The article of footwear of any of paras. 50 through 53, wherein
a portion of the spring plate is exposed on a bottom of the
article. [0140] 55. The article of footwear of any of paras. 50
through 54, wherein the midsole is external relative to the upper.
[0141] 56. The article of footwear of any of paras. 50 through 55,
wherein the article comprises multiple separate outsoles engaged
with the bottom of the spring plate. [0142] 57. The article of
footwear of any of paras. 50 through 56, wherein the spring plate
lacks on open region. [0143] 58. The article of footwear of any of
paras. 50 through 57, wherein the front portion of the spring plate
is downwardly bent relative to the rear portion of the spring plate
at an angle between about 10 degrees and about 25 degrees.
* * * * *