U.S. patent application number 12/777100 was filed with the patent office on 2010-11-11 for footwear with balancing structure.
This patent application is currently assigned to i-Generator L.L.C.. Invention is credited to Simon Luthi, Peter Rueegger, Peter Valois.
Application Number | 20100281716 12/777100 |
Document ID | / |
Family ID | 43061454 |
Filed Date | 2010-11-11 |
United States Patent
Application |
20100281716 |
Kind Code |
A1 |
Luthi; Simon ; et
al. |
November 11, 2010 |
FOOTWEAR WITH BALANCING STRUCTURE
Abstract
The inventive subject matter is directed to a sole unit for an
item of footwear having a forefoot region, a midfoot region and a
rearfoot region. The mid foot region includes a balancing structure
having a curved surface profile that rotates around (i) an axis for
fore-aft pivoting or balancing and/or (ii) an axis for
lateral-medial pivoting or balancing, when the item of footwear is
under a normal load of a user.
Inventors: |
Luthi; Simon; (Lake Oswego,
OR) ; Rueegger; Peter; (Portland, OR) ;
Valois; Peter; (Portland, OR) |
Correspondence
Address: |
GANZ LAW, P.C.
P O BOX 2200
HILLSBORO
OR
97123
US
|
Assignee: |
i-Generator L.L.C.
Portland
OR
|
Family ID: |
43061454 |
Appl. No.: |
12/777100 |
Filed: |
May 10, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61177215 |
May 11, 2009 |
|
|
|
Current U.S.
Class: |
36/30R |
Current CPC
Class: |
A43B 13/143
20130101 |
Class at
Publication: |
36/30.R |
International
Class: |
A43B 13/12 20060101
A43B013/12 |
Claims
1. A sole unit for an item of footwear, comprising: a forefoot
region, a midfoot region and a rearfoot region; wherein the mid
foot region comprises a balancing structure having a curved surface
profile that rotates around (i) an axis for fore-aft pivoting or
balancing and/or (ii) an axis for lateral-medial pivoting or
balancing, when the item of footwear is under a normal load of a
user.
2. The sole unit of claim 1 wherein the a balance structure is
defined by material having a higher durometer than the durometer of
the adjacent forefoot and rearfoot regions so that the forefoot and
rearfoot regions preferentially compress relative to the midfoot
region, leaving the midfoot region as a protrusion for
balancing.
3. The sole unit of claim 1 wherein the midfoot region has a
durometer of about 60 C to about 80 C, and the forefoot and midfoot
regions each have a durometer at least 10 C below the durometer of
the midfoot region.
4. The sole unit of claim 3 wherein the durometer of the balancing
structure is about 60 C to about 80 C.
5. The sole unit of claim 1 wherein the balancing structure
comprises a rounded structure protruding from a recessed midfoot
area.
6. The sole unit of claim 5 wherein the rounding of the structure
allows for fore-aft rocking.
7. The sole unit of claim 5 wherein the rounding of the structure
allows for lateral-medial rocking.
8. The sole unit of claim 5 where the rounding of the structure
allows for both fore-aft rocking and lateral-medial rocking.
9. The sole unit of claim 1 wherein the curved profile is provided
by a polygonal structure having more than four sides.
10. The sole unit of claim 1 wherein the curved profile is provided
by a balancing structure having varying durometer.
11. The sole unit of claim 1 wherein the sole unit comprises a
monolithic structure.
12. The sole unit of claim 1 wherein the monolithic structure is of
a heterogeneous nature and the balancing structure has a relatively
higher durometer than adjacent forefoot and rearfoot regions.
13. The sole unit of claim 1 wherein the sole unit comprises a
modular assembly of a plurality of layers, one or more layers
contributing to the structure of the balancing structure.
14. The sole unit of claim 1 wherein one layer comprises a core
layer with the balancing structure disposed thereon.
15. The sole unit of claim 14 wherein a second layer comprises a
stability layer comprising a cushioning element.
16. The sole unit of claim 15 wherein the core layer is disposed
above the stability layer and the stability layer has a window or
frame through which the balancing structure protrudes.
17. The sole unit of claim 15 wherein the stability layer is
disposed below the core layer and an outsole layer is disposed
below the stability layer.
18. The sole unit of claim 1 wherein the sole unit comprises at
least one layer serving as a midsole.
19. The sole unit of claim 18 wherein the midsole layer comprises a
resilient material having a lower durometer than the durometer of
the balancing structure.
20. The sole unit of claim 19 wherein the balancing structure is
formed on a core layer comprising a resilient material having a
relatively higher durometer than the midsole layer.
Description
RELATED APPLICATIONS
[0001] This application claims priority to and the benefit of U.S.
Provisional Patent Application No. 61/177,215, filed May 11, 2009,
by Simon Luthi et al., entitled FOOTWEAR WITH BALANCING STRUCTURE,
which is incorporated herein by reference as if included in its
entirety for all purposes.
BACKGROUND
[0002] The inventive subject matter disclosed herein generally
relates to various novel embodiments of a sole system for footwear.
More particularly, the inventive subject matter is directed to a
sole configuration that in use provides a midfoot region that
serves as a fore-aft balance point and/or lateral/medial balancing
or pivoting point.
[0003] Over recent years there has been increasing awareness of the
vital role that musculature health benefits from a healthy and
strong, flexible set of core muscles. Stable core provides the
foundation for all day to day activity, stabilizing and balancing
the lower back and pelvic region, neck, upper back and shoulder
blade region. Additionally it strengthens the muscles of the pelvic
floor region.
[0004] Common complaints that may be attributed to inactive or weak
core muscles include: low back pain, shoulder and neck pain,
hamstring tightness. Core muscles may also suffer during and after
pregnancy, causing leg pain, groin pain, and knee pain.
[0005] Research has shown that when a person has back pain/leg pain
and neck/shoulder blade pain the muscles around these areas `switch
off` during daily or routine activities, which breaks down the
stabilizing ability of the muscle system. When the pain resolves
the muscles do not automatically `switch on` again, leading to
ongoing poor function and potential for recurrence of pain.
[0006] The core muscles can be all or any of this set: rectus
abdominus, transverse abdominus, internal and external obliques,
pelvic floor, multifidi, erector spinae, longissimus throacis,
diaphragm, and gluteus maximus and medius. Weakness and
inflexibility in core muscles has been attributed to or contributed
to the conditions such as back pain, sciatica, for example.
Development of core muscles has also been a part of rehabilitation
and conditioning programs for recovery from or prevention of
injuries and degenerative conditions.
[0007] Athletic and dance performance can also be improved with
improvements in an individual's ability to balance. Unfortunately,
balancing exercises and drills typically require trips to the gym
or other workout location; they are not easily conducted in
connection with every-day activities.
[0008] One or more of the core muscles are activated when a person
is engaged in certain upright balancing positions or movements.
Unfortunately, few people find the time to make an effort on a
day-to-day basis to engage in balancing or other fitness activities
that help activate and thereby strengthen and maintain core
muscles. Accordingly, there is a need for apparatuses and methods
that will allow people to make core strength development and
maintenance an anytime, everyday part of their lives.
[0009] There is also a need for systems that will help athletes,
dancers and others improve their balance with convenient, anytime,
anyplace apparatuses and methods.
SUMMARY
[0010] The inventive subject matter overcomes the aforementioned
problems and others via an innovative design for a sole unit for
footwear. It is believed that the inventive subject matter helps
strengthen muscles, retrain and activate inactive muscles, correct
movement patterns, and help prevent recurrence and long term
disability.
[0011] The inventive subject matter is directed to a sole unit for
an item of footwear having a forefoot region, a midfoot region and
a rearfoot region. The mid foot region includes a balancing
structure having a curved surface profile that rotates around (i)
an axis for fore-aft pivoting or balancing and/or (ii) an axis for
lateral-medial pivoting or balancing, when the item of footwear is
under a normal load of a user.
[0012] These and other embodiments are described in more detail in
the following detailed descriptions and the figures.
[0013] The foregoing is not intended to be an exhaustive list of
embodiments and features of the present inventive concept. Persons
skilled in the art are capable of appreciating other embodiments
and features from the following detailed description in conjunction
with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The following figures show embodiments according to the
inventive subject matter, unless noted as showing prior art.
[0015] FIG. 1 shows a side elevation of one possible embodiment of
an item of footwear (left shoe) with a midfoot structure for
balancing.
[0016] FIG. 2A shows a bottom perspective view of the sole unit
from the embodiment of FIG. 1.
[0017] FIG. 2B shows an assembly view of possible components for
the sole unit of FIGS. 1-2A.
[0018] FIG. 3A shows a side elevational view of certain assembled
components from the sole unit of FIG. 2B.
[0019] FIG. 3B shows a bottom elevational view of the sole unit of
FIG. 3A.
[0020] FIG. 4 shows a side elevational view of another possible
embodiment of an item of footwear (left shoe), a sandal-style shoe,
with a midfoot structure for balancing.
[0021] FIG. 5 shows a side elevational view of another possible
embodiment of an item of footwear (left shoe), a high-heel
platform-style shoe, with a midfoot structure for balancing.
DETAILED DESCRIPTION
[0022] Representative embodiments according to the inventive
subject matter are shown in FIGS. 1-5, wherein the same or
generally similar features share common reference numerals.
[0023] The inventive subject matter is directed to a sole unit for
an item of footwear having a forefoot region, a midfoot region and
a rearfoot region. The mid foot region includes a balancing
structure having a curved surface profile that rotates around (i)
an axis for fore-aft pivoting or balancing and/or (ii) an axis for
lateral-medial pivoting or balancing, when the item of footwear is
under a normal load of a user.
[0024] Before expanding upon the foregoing and other inventive
features, an overview of foot anatomy will help illustrate the
invention, and facilitate a better understanding of it. The
forefoot is composed of five toes and their connecting long bones,
the metatarsals. Each toe, or phalanx, is made up of small bones,
the phalanges. The big toe, or hallux has two phalanges, two
joints, the interphalangeal joints; and two tiny, round sesamoid
bones that enable it to move up and down. The other four toes each
have three bones and two joints. The second row of phalanges is
connected to the metatarsal heads by five metatarsal phalangeal
joints at the ball of the foot, i.e., where the foot is normally at
its widest.
[0025] The midfoot has five irregularly shaped tarsal bones, which
form the foot's arch. The rearfoot is composed of three joints and
links the midfoot to the ankle (talus). The top of the talus is
connected to the two long bones of the lower leg (tibia and
fibula), forming a hinge that allows the foot to move up and down
(dorsiflexion/plantar flexion).
[0026] The heel bone (calcaneus) is the largest bone in the foot.
It joins the talus to form the subtalar joint, which enables the
foot to rotate at the ankle (eversion/inversion).
[0027] The inventive subject matter is implemented through a sole
unit that provides a balancing structure that enables balancing
along one or more axes of the shoe as described below. When the
upper of the shoe balances on the balance structure, core muscles
are activated and benefited as described in the background and
summary sections.
[0028] A sole unit may be broken down into regions generally
corresponding to the forefoot, midfoot, and heel bone (which is
also referred to herein as the "rearfoot").
[0029] As used herein, "footwear" refers to any item for supporting
the foot and engaging the ground and encompasses shoes, sandals,
boots, slippers, over-shoes, athletic shoes, dance shoes, and other
footwear articles. "Cushioning elements" refers to basic shock
absorbing, energy return, and/or protective underfoot materials or
structures that are intended to react to the forces of foot strike
by providing force attenuation, dissipation, dampening, or energy
return (spring), which are typically included on sports and
athletic shoes. Traditionally, a cushioning element comprises a
consistent and uniform layer of shock absorbing and protective
material, such as such as EVA or polyurethane, placed in a shoe
between the foot and the ground. However, in relatively recent
years there has been a trend towards customized placements of
varying cushioning materials and structures under a foot. Nowadays,
common cushioning elements may be based on EVA or polyurethane
foam, visco-elastomers of foam or gels, fluid filled bladders,
mechanical springs or resiliently collapsible mechanical
structures, fluid (e.g., air, viscous gel) springs, or any
combination of the foregoing.
[0030] For example polymer spring units have been placed in
portions in the sole unit receiver, particularly the heel portion,
and in some cases the forefoot portion. Mechanical polymer springs
may be formed from an injected thermoplastic, such as Hytrel
polymer, PEBAX, and TPU, as well as other resilient polymers,
thermo-set plastics, and metallic materials known in the art, alone
or in combination. See, for example, U.S. Pat. No. 5,461,800, which
is hereby incorporated by reference in its entirety. The U.S. Pat.
No. 5,461,800 discloses a foamless midsole unit, comprising upper
and lower plates sandwiching transverse cylindrical units formed of
resilient polymer. See also, for example, U.S. Pat. Nos. 4,910,884,
6,625,905, and 5,337,492. Other forms of mechanical springs, such
as leaf-spring structures are also contemplated.
[0031] As used herein a "sole unit" generally may comprise a
midsole or cushioning element for energy absorption and/or return;
or an outsole material for surface contact and abrasion resistance
and/or traction; or a single unit providing such midsole or outsole
functions. While a sole unit would generally extend the length of
the shoe, a sole unit could also comprise a unit that extends for a
lesser area, such as, just the forefoot or rearfoot portion, or
some other area of lesser length or width.
[0032] A sole unit may include cushioning elements in accordance
with any of the foregoing cushioning elements. Contemplated
fabrication methods for the sole unit components include molding,
injection molding, blow molding, direct-injection molding, one-time
molding, composite molding, insert molding, co-molding separate
materials, or other techniques known in the art, alone or in
combination. Contemplated fabrication or assembly methods include
adhesives, bonding agents, welding, mechanical bonding, or
interlocking shapes, alone or in combination.
[0033] Dampening elements, which are a form of cushioning element
(as defined herein), may also be incorporated into the sole units
and/or sole unit receivers disclosed herein. "Dampening" generally
refers to the ability of certain materials to reduce the amplitude
of oscillations, vibrations, or waves. In footwear, shock from
impact may generate compression waves or other vibrations within
the sole system. Contemplated dampening materials include
visco-elastomers. In some instances, plain elastomer materials may
be used as dampeners; however, they may not provide as desirable
dampening qualities on the spring unit as a visco-elastomer.
Example materials for a visco-elastic dampener include any number
of polymers, including polyurethanes and polyethylenes in foam or
gel form, fabricated by conventional molding practices or by film.
Other suitable visco-elastomers are known to persons skilled in the
art. Contemplated fabrication methods for visco-elastomers include
molding, injection molding, blow molding, direct-injection molding,
one-time molding, composite molding, insert molding, co-molding
separate materials, or other techniques known in the art, alone or
in combination. Contemplated fabrication or assembly methods
include adhesives, bonding agents, welding, mechanical bonding, or
other mechanical or chemical fastening means know to persons in the
art, alone or in combination.
[0034] The outsole for a sole assembly may include rubber, leather,
felts, EVA, foam, and other cushioning technologies, and
combinations of the foregoing. The outsole may have any kind of
traction surface, including, for example, smooth and patterned
surfaces, cleated surfaces, and spiked surfaces. As is well-known
in the art, a single unit may be formed to provide both a
cushioning element and outsole functionalities. For example, EVA
and PU materials may be formed into a multifunctional unit.
[0035] FIGS. 1-3B show one possible embodiment of an item of
footwear 10 with an upper 12 and a sole unit 14. The sole unit has
a midfoot region having a midfoot structure 16 for balancing. The
midfoot balancing structure may be disposed in and protrudes from a
recessed midfoot region, as seen best in FIG. 2A. The recessed area
from which balancing structure 16 protrudes is defined by parallel
arms 18a and 18b that have a concave shape and run along lateral
and medial sides of the sole unit.
[0036] The balancing structure provides a surface profile 20 that
is raised relative to the forefoot regions and rearfoot regions and
which thereby allows a user to balance between or pivot on an off
the forefoot and rearfoot regions. The balancing structure may also
provide a surface profile 20 that is raised relative to lateral
and/or medial sides of the sole to provide for balancing between or
pivoting on and off the lateral and/or medial sides of the shoe.
The surface profile provides at least one tangential point 22 for
pivotal rotation of the sole unit. A single tangential point would
be provided in the case of a surface profile in the nature of a
hemisphere. However, more than one tangential point may be provided
for surface contact along an axis of rotation, as noted below in
the example of a balancing structure in the nature of a cylinder.
The pivoting occurs around a rotational center point 24, which may
be at an intersection of orthogonal axes X-X, Y-Y, and Z-Z, as
indicated in FIGS. 3A-3B. Axis X-X runs vertically in between the
lateral and medial sides of the sole unit. Axis Y-Y runs
horizontally along the longitudinal axis of the sole unit. And axis
Z-Z runs transversely to the longitudinal axis of the sole unit,
through the midfoot's lateral and medial sides. In the case of
fore-aft balancing or pivoting, the balancing structure rotates
around axis Z-Z. In the case of lateral-medial balancing or
pivoting, the balancing structure rotates around axis Y-Y, as
indicated by the arrows. Heel-to-toe rotation may occur around axis
X-X.
[0037] The balancing structure may be resilient in nature, e.g.,
made of a foamed EVA or PU or a mechanical or elastomeric spring
structure. Alternatively, it may be made of a non-resilient
material or structure using, e.g., metal, wood, hard plastic,
etc.
[0038] The balancing structure 16 may be raised by making the
physical dimensions of the balancing structure thicker than
adjacent forefoot or midfoot materials or structures so that the
balancing surface protrudes. Alternatively, the balancing structure
need not protrude relative to the forefoot or rearfoot but can be
coplanar or even relatively recessed when the item of footwear is
not under the normal load of a wearer. By selecting materials or
structures for the forefoot and rearfoot that will selectively
compress or collapse under the normal loads (e.g., standing,
walking, running, dancing, etc) of a wearer relative to the
balancing structure, there is an effective protrusion of the
balancing structure to allow for balancing or pivoting.
[0039] As the Figures indicate, balancing structure 16 is located
substantially or entirely within the midfoot. However, so long as
the balancing surface profile 16, with a center point of rotation
for one or both of axes Z-Z and Y-Y, is generally disposed in the
midfoot region, the balancing structure may extend into the midfoot
or rearfoot regions. An example of a balancing structure that might
have just one of the axes Z-Z and Y-Y in the midfoot region, is a
cylinder with ends disposed along axis Z-Z. The cylinder would
rotate around that axis but not around axis Y-Y. A cylinder also
provides a continuum of tangential points 22. An axis for rotation
around axis Y-Y could be provided in the forefoot or rearfoot
region, e.g., a cylinder with ends oriented along axis Y-Y or a
hemispherical like structure which could provide for rotation along
both axes X-X and Y-Y.
[0040] In the embodiment shown, balancing structure 16 is rounded
so as to allow fore-aft rocking and lateral-medial rocking. It also
allows toe-heel swiveling. In this embodiment, the balancing
structure is more oblong or egg-shaped, with the elongated
dimension following the Y-Y axis along the longitudinal axis of the
sole unit. This configuration helps provide for stability and
control. The curvatures may be relatively shallow along the Y-Y
and/or Z-Z axes to allow for more gradual fore-aft rocking than
would be provided by a more hemispherical shape, for example, with
steeper curves. However, from the teachings herein, persons skilled
in the art will recognize the structural configuration can be in
various forms to achieve desired degrees of rocking, stability and
controllability. For example, for more aggressive balancing and
control, a larger, more-hemispherical configuration may be
implemented.
[0041] As seen in the various figures, the sole unit may provide
toe-spring so that the forefoot region in an unloaded condition
curves upwardly a predetermined degree. Such curvature may
facilitate fore-aft pivoting.
[0042] The balancing structure 16 need not be rounded to allow
pivoting; it can also be in other geometrical forms that allow for
pivoting around an axis, for example, polygonal shapes of more than
four sides that approximate a curve. Any actually curved surface
profiles or approximately curved surface profiles that serve to
provide rotation around an axis shall be deemed to have a "curved
surface profile," as used herein. It could even be square by
constructing the outer portion to have a lower durometer than an
inner portion so that under load the outer portion compresses or
collapses to a shape that allows pivoting. Any such functionally
curved surface profiles shall also be a "curved surface profile, as
used herein".
[0043] The sole unit may be formed as a single monolithic unit out
of known or to be discovered molded materials. A monolithic
structure may have a homogeneous or heterogeneous composition. It
may have varying material properties, such as varying density,
durometer, spring rates, etc. The sole unit may also be an assembly
of components. An example of a sole unit have multiple components
is shown in FIGS. 2A-3B. Upper 12 is attached to a core layer 26
that includes balancing structure 16. The balancing structure could
also be disposed on other components of the sole unit. Or it could
be a discrete unit affixed to, pocketed within, sandwiched between,
or otherwise structurally coupled to the sole unit. A full length
core layer that is relatively stiff but with some resilience can
advantageously provide lever arms on either side of the balancing
structure to help with balancing and pivoting. It can also help
distribute forces.
[0044] At least the balancing structure of the core layer would be
of a relatively high density EVA or other resilient material (all
durometer expressed herein are Asker C) so as to provide the
pivoting functions discussed above relative to adjacent regions or
sections of the sole unit.
[0045] Disposed below core layer 26 is a relatively low durometer
stability layer. The stability layer 28 may be, for example, an EVA
having a density and durometer that is relatively lower than the
core layer 26. The stability layer in this example provides a
window framed in part by arms 18A and 18B. The window allows the
balance structure 16 on the core layer to extend through and be
exposed to the ground in use. The stability layer provides
structural stability and/or serves as a cushioning element, as does
a traditional midsole for an athletic shoe.
[0046] In some embodiments, the balancing structure in the midfoot
region has a relatively higher overall durometer than the overall
durometer in the forefoot region or rearfoot region. In such
embodiments, there should be a difference of at least about 10 C.
In some embodiment, the core layer or at least the balancing
structure in the midfoot region has a durometer of from about 60 C
to about 80 C and the stability layer in a forefoot or rearfoot
region adjacent the stability structure has a durometer of from
about 40 to about 50 C.
[0047] Disposed below the forefoot region of the stability layer is
forefoot outsole layer 32. Disposed below the rearfoot region of
the stability layer is forefoot outsole layer 34. These layers may
be, for example, rubber or other known or to be discovered
material.
[0048] Although the core layer 26 and stability layer 28 are shown
as a full-length structures, either could reside under just a
portion of the foot, with other structures extending to other
areas. Conversely, although outsole layers 32 and 34 are shown each
covering just a portion of the foot, a full length outsole could be
provided. A full length outsole could have a window similar to
window 30 or instead have a thin layer of material in the area for
the window that conforms to the shape of the balancing structure.
Alternatively, the balancing structure could be formed in and of
outsole material.
[0049] The sole system shown can have the components permanently
affixed together or removably fixed together for interchange or
replacement of components. The latter form of assembly shall be
referred to as a modular construction. One advantage of a modular
assembly is that a user can not only replace worn components, but
the user can also tune the assembly for a desired effect. For
example, a set of balancing structures could be provided ranging
from ones with relatively shallower curves or less protrusion to
ones with deeper curves and greater protrusion. The balancing
structure with shallower curves would be used initially for easier
balancing and control. The user would progress to curves or
protrusion profiles that would more aggressively challenge and
develop the users balance, control and muscle development.
[0050] The inventive subject matter can be used in a variety of
shoe types. For example, FIG. 4 shows a side elevational view of
another possible embodiment of an item of footwear, a sandal-style
shoe, with a midfoot structure for balancing. FIG. 5 shows a side
elevational view of another possible embodiment of an item of
footwear, a high-heel platform-style shoe, with a midfoot structure
for balancing.
[0051] Persons skilled in the art will recognize that many
modifications and variations are possible in the details,
materials, and arrangements of the parts and actions which have
been described and illustrated in order to explain the nature of
the inventive subject matter, and that such modifications and
variations do not depart from the spirit and scope of the teachings
and claims contained therein.
[0052] All patent and non-patent literature cited herein is hereby
incorporated by references in its entirety for all purposes.
* * * * *