1. Technical field
[0001] The present invention relates to a sole for a shoe, in particular a sports shoe.
2. Prior art
[0002] By means of soles, shoes are provided with a plethora of properties which can be
pronounced in various strengths, depending on the specific type of shoe. Primarily,
shoe soles typically have a protective function. They protect the foot of the respective
wearer, due to their increased stiffness compared to the shoe shaft, against injuries
caused by, e.g., sharp objects on which the wearer may tread. Furthermore, the shoe
sole, due to an increased abrasion resistance, usually protects the shoe against excessive
wear. In addition, shoe soles can improve the grip of the shoe on the respective ground
and thus enable faster movements. A further function of a shoe sole can consist in
its providing certain stability. Furthermore, a shoe sole can have a cushioning effect,
for example, by absorbing the forces occurring during contact of the shoe with the
ground. Finally, a shoe sole can protect the foot from dirt and spray water or provide
a plurality of other functionalities.
[0003] In order to satisfy this plethora of functionalities, different materials are known
from the prior art from which shoe soles can be manufactured. Exemplarily, shoe soles
made from ethylene-vinyl-acetate (EVA), thermoplastic polyurethane (TPU), rubber,
polypropylene (PP) or polystyrene (PS) are mentioned here. Each of these various materials
provides a special combination of different properties which are more or less well-suited
for the specific requirements of the respective shoe type. TPU, for example, is very
abrasion-resistant and tear-proof. Furthermore, EVA distinguishes itself by a high
stability and a relatively good cushioning effect. In addition, the use of expanded
materials, in particular of expanded thermoplastic urethane (eTPU), was taken into
consideration for the manufacture of a shoe sole. Thus, for example,
WO 2005/066250 A1 describes methods for the manufacture of shoes whose shoe shaft is adhesively connected
to a sole on the basis of foamed thermoplastic urethane. Expanded thermoplastic urethane
distinguishes itself by a low weight and particularly good elasticity and cushioning
properties.
[0004] In addition to cushioning and absorbing the shock energy produced when the foot treads
on the ground, i.e. a cushioning in vertical direction, it is further known form prior
art that during running, also shear forces occur in horizontal direction, in particular
on grounds where a shoe has a good grip and the shoe is hence stopped abruptly together
with the foot when contacting the ground. In case these shear forces cannot be absorbed
at least partially by the ground and/or the sole of the shoe, the shear forces are
transmitted with undiminished effect to the movement apparatus, in particular the
knee. This easily leads to an excessive burdening of the movement apparatus and promotes
injuries. On the other hand, excessive shear capacity of the shoe sole would mean
a loss of stability, in particular during faster running, which would lead to an increased
risk of injuries. The increased shear capacity can also be undesired in specific regions
of the sole, since these regions precisely serve to stabilize the foot. Furthermore,
an increased shear capacity, e.g. in the area of the toes or of the midfoot, can give
the wearer a sensation of slipping of the shoe during running, which can reduce the
wear comfort.
[0005] In order to solve this problem, sole constructions are known from the prior art,
e.g. from
DE 102 44 433 B4 and
DE 102 44 435 B4, which can absorb in a way that does not strain the joints a part of the shear forces
occurring during running. However, a disadvantage of these constructions consists
in the fact that such soles are composed of several independent individual parts,
have a fairly high weight and are expensive and complex in manufacture.
[0006] Moreover,
US 2005/0150132 A1 discloses footwear (e.g., shoes, sandals, boots, etc.) that is constructed with small
beads stuffed into the footbed, so that the beads can shift about due to pressure
on the footbed by the user's foot during normal use.
US 7,673,397 B2 discloses an article of footwear with support assembly having a plate and indentations
formed therein.
US 8,082,684 B2 discloses a sole unit for a shoe having at least one decoupling track between regions
of sole unit allowing for the decoupling of the regions in response to forces from
foot-ground contact.
DE 10 2011108 744 A1 discloses a method for the manufacture of a sole or part of a sole for a shoe.
WO 2007/082838 A1 discloses foams based on thermoplastic polyurethanes.
US 2011/0047720 A1 discloses a method of manufacturing a sole assembly for an article of footwear. Finally,
WO 2006/015440 A1 discloses a method of forming a composite material.
[0007] Starting from the prior art, it is therefore an objective of the present invention
to provide better soles for shoes, in particular for sports shoes. A further objective
is to provide improved possibilities by means of which the shear capacity of shoe
soles can be selectively influenced in specific regions of the sole.
3. Summary of the invention
[0008] According to a first aspect of the present invention, this problem is solved by a
sole for a shoe, in particular a sports shoe, comprising a cushioning element which
comprises randomly arranged particles of an expanded material. The sole further comprises
a control element free from expanded material, wherein the control element reduces
shearing motions in a first region of the cushioning element compared to shearing
motions in a second region of the cushioning element.
[0009] The use of a cushioning element comprising expanded material is particularly advantageous
for the construction of a shoe sole, since this material is very light, but is able,
at the same time, to absorb the shock energy when the foot treads on the ground and
to restore it to the runner. This increases the running efficiency and reduces the
(vertical) impact burden upon the movement apparatus. A further advantage is provided
by the use of randomly arranged particles of the expanded material. These considerably
facilitate the manufacture of such a sole, since the particles a particularly easy
to handle and, due to their random arrangement, no orientation is necessary during
manufacture.
[0010] The use of a control element allowing for selectively controlling the shear capacity
of the cushioning element furthermore allows for constructing soles that can also
absorb and/or cushion horizontal shear forces which otherwise would have a direct
impact on the movement apparatus, in particular the joints. This further increases
the wear comfort of the shoe and the efficiency of the runner and prevents at the
same time from injuries and wear of the joints. Since this control element is preferably
free from expanded material, is has sufficient strength for complying with its control
function.
[0011] In a preferred embodiment, the particles of expanded material comprise one or more
of the following materials: expanded ethylene-vinyl-acetate (eEVA), expanded thermoplastic
urethane (eTPU), expanded polypropylene (ePP), expanded polyamide (ePA), expanded
polyether block amide (ePEBA), expanded polyoxymethylene (ePOM), expanded polystyrene
(PS), expanded polyethylene (ePE), expanded polyoxyethylene (ePOE), expanded ethylene
propylene diene monomer (eEPDM). According to the requirement profile of the sole,
one or more of these materials can be advantageously used for the manufacture of the
sole due to their substance-specific properties.
[0012] In a further preferred embodiment, the control element comprises one or more of the
following materials: rubber, non-expanded thermoplastic urethane, textile materials,
PEBA as well as foils and foil-like materials.
[0013] In a further preferred embodiment, the first region of the cushioning element comprises
a higher intrinsic shear resistance than the second region of the cushioning element.
The use of such a cushioning element with regions of different intrinsic shear resistance
in combination with a control element, which locally influences the shear capacity
of the cushioning element, offers great freedom and various adaption possibilities
in the construction of a shoe sole.
[0014] In an embodiment, the control element has, in a first control region which influences
the shearing motion of the cushioning element in the first region, a greater thickness
and/or fewer holes than in a second control region which influences the shearing motion
of the cushioning element in the second region. Based on the thickness and the number
and size of the holes, etc., the bending and deformation resistance of the control
element can be determined, for example. These properties of the control element can,
for their part, influence the shear and the bending capacity of the different regions
of the cushioning element.
[0015] In a preferred embodiment, the cushioning element is provided as a component of a
midsole. In a further preferred embodiment, the control element is provided as a part
of an outsole.
[0016] By means of the construction of the cushioning element as a part of a midsole and/or
of the control element as a part of an outsole, the number of different functional
components of the sole and the shoe can be minimized and, at the same time, the adaption
and control possibilities of the sole properties can be increased. This simplifies,
e.g., the construction of the shoe and can reduce its weight considerably. Furthermore,
additional composite materials such as adhesives for bonding the different elements
of the sole and the shoe are not required. Consequently, the manufacture of the shoe
is eventually more cost-effective together with improved functionality and furthermore
offers improved recycling possibilities, since materials of common material classes
are preferably used.
[0017] In a further embodiment, the outsole comprises a decoupling region that is not directly
attached to the second region of the cushioning element of the midsole. As explained
in detail further below, this enables to further influence and/or increase the shear
capacity of the sole. So, for example, a control element provided as a part of an
outsole can be bonded by a gel or the like to a cushioning element provided as a part
of a midsole. The gel allows a further shearing effect between the control element
and the cushioning element and thus allows absorbing higher shear forces.
[0018] According to a further aspect of the invention, the control element and the cushioning
element can be manufactured from materials of a common material class, in particular
from thermoplastic urethane. This allows a simplified manufacture of the sole and
the shoe. In particular, materials from a common material class can often be bonded
with each other and processed together in a significantly easier way than materials
from different classes.
[0019] According to a further aspect of the invention, the first region is located in the
medial region of the midfoot and the second region in the lateral region of the heel.
The shear forces occurring during running are especially produced when the foot contacts
the ground. This happens typically with the lateral region of the heel. For this reason,
a good shear capacity of the sole for absorbing the shear forces is desirable there.
In the medial region of the foot, however, a supporting effect and increased stability
are often desired. This allows a better pushing the foot off the ground and can furthermore
prevent a pronation of the foot which can lead to irritations and injuries.
[0020] According to a further aspect of the invention, the control element further increases
the bending resistance of the cushioning element in the first region compared to the
second region. In particular, a control element designed as a part of an outsole can
provide this functionality.
[0021] According to a further aspect of the invention, the sole comprises a frame made from
non-expanded material, in particular from ethylene-vinyl-acetate, which surrounds
at least a part of the cushioning element. Such a frame enables, for example, a further
control of the shear capacity and can also be used to increase the stability of the
sole.
[0022] In a preferred embodiment, the cushioning element allows a shearing motion of a lower
sole surface relative to an upper sole surface in longitudinal direction of more than
1 mm, preferably more than 1.5 mm and particularly preferably more than 2 mm. These
values offer a good balance between a sufficient stability of the shoe sole and a
high absorption capacity for horizontal shear forces.
[0023] Preferably, the control element is laser-cut from a blank. For example, the control
element can be provided in form as an outsole, or part of an outsole, which is laser-cut
from a blank.
[0024] In the simplest form, the blank may be provided as a material layer comprising, for
example, one or more of the materials suitable for the manufacture of a control element/outsole
mentioned above. It is also possible, for example, that the blanks are provided in
different sizes, thickness, with predefined holes, bulges, etc. and they may also
comprise the general outline of a foot or sole.
[0025] Laser-cutting the control element can provide for a large freedom in design for the
control element. It can also provide for the opportunity of an individual customization
of the control element, sole and shoe. It may, for example, allow for numerous fashion
designs, an individualization of each sole or shoe. The customization may be sport
specific or according to typical movements of a customer or otherwise customer related.
Furthermore, the laser-cutting may automated to a large degree and maybe based on,
e.g., online tools or other ordering methods.
[0026] The above mentioned customization features and online ordering may, however, also
be used in connection with other embodiments of inventive soles and shoes described
herein or otherwise conceivable, without the control element necessarily being laser-cut
from a blank.
[0027] A further aspect of the present invention relates to a shoe, in particular a sports
shoe, with a sole according to one or more of the preceding embodiments of the invention.
Here, individual aspects of the mentioned embodiments of the invention can be advantageously
combined with one another, depending on the requirement profile for the sole and the
shoe. Furthermore, it is possible to leave single aspects aside, if these should be
irrelevant for the respective purpose of the shoe.
4. Brief description of the figures
[0028] In the following detailed description, currently preferred examples of implementations
and embodiments of the sole according to the invention are described with reference
to the following figures:
- Fig. 1
- Embodiment of a shoe sole with a midsole and an outsole which selectively influences
the shear capacity and the bending capacity of the midsole. The sole further comprises
a reinforcing element which is partially embedded in the midsole, as well as a heel
clip;
- Fig. 2
- Shoes with different soles which were used for the measurements of Figs. 3a - 9;
- Figs. 3a-b
- Comparison of the vertical compression of a midsole made from eTPU and a midsole made
from EVA when the foot touches the ground;
- Fig. 4
- Measurements of the vertical compression of a midsole made from eTPU and a midsole
made from EVA during an entire step cycle;
- Figs. 5a-b
- Comparison of local material stretch in the lateral side wall of a midsole made from
eTPU and a sole made from EVA during a rolling motion of the foot from the heel region
to the forefoot region during a step;
- Figs. 6a-c
- Measurements of the relative displacement of two measurement points at the opposite
ends of the measurement sections represented in Figs. 7a-c during a complete step cycle for three different soles;
- Figs. 7a-c
- The measurement points used for the measurements in Figs. 6a-c are each located at the ends of the measurement sections delineated in Figs. 7a-c;
- Figs. 8a-c
- Comparison of the horizontal shear effect exerted on the sole material of three different
midsoles when touching the ground with the lateral heel region;
- Fig. 9
- Measurements of the shear effects in the heel region of the sole material of different
midsoles in longitudinal direction (AP direction) during an entire step cycle;
- Figs. 10a-d
- Further measurements of the shear effects in the heel region of the sole material
of various midsoles in longitudinal direction (AP direction) and in medial direction
(ML direction) during an entire step cycle;
- Fig. 11
- Average values of several measurements of the shear effects in the heel region of
the sole material of respective different midsoles in longitudinal direction (AP direction)
during an entire step cycle;
- Fig. 12
- Average values of several measurements of the shear effects in the heel region of
the sole material of respective different midsoles in medial-lateral direction (ML
direction) during an entire step cycle;
- Figs. 13a-e
- Representation of the plantar shearing effect on the sole material of different midsoles,
at the end of a step, when the foot is pushed off the ground in the forefoot region
(cf. Fig. 13e);
- Figs. 14a-c
- Preferred embodiment of a shoe with a sole according to an aspect of the present invention;
- Figs. 15a-c
- Further preferred embodiment of a shoe with a sole according to an aspect of the present
invention;
- Figs. i6a-b
- Preferred embodiment of a shoe sole with a midsole and an outsole which selectively
influences the shear capacity and the bending capacity of the midsole;
- Fig. 17
- Particularly preferred embodiments of a shoe sole with a midsole and an outsole which
selectively influences the shear capacity and the bending capacity of the midsole;
- Fig. 18
- Schematic representation of possible embodiments for outsoles which selectively influence
the shear and bending capacity of a midsole;
- Figs. 19,20
- Schematic cross-section in ML direction through two embodiments of a midsole which
comprises a first and a second plate element which can perform a sliding movement
relative to each other;
- Figs. 21a-b
- Embodiment of a shoe according to the invention with an embodiment of a sole according
to the invention comprising a control element laser-cut from a blank; and
- Figs. 22a-d
- Further currently preferred embodiments of shoes according to the invention with embodiments
of shoe soles according to the invention.
5. Detailed description of preferred embodiments
[0029] In the following detailed description, currently preferred embodiments of the invention
relating to sports shoes are described. It is, however, emphasized that the present
invention is not limited to these embodiments. The present invention can, for example,
also be used for safety shoes, casual shoes, trekking shoes, golf shoes, winter shoes
or other shoes as well as for protective clothing and paddings in sports apparel and
sports equipment.
[0030] Fig. 1 shows a sole
100 according to an aspect of the present invention. The sole
100 comprises a cushioning element
110 which comprises randomly arranged particles of an expanded material, as well as a
control element
130 which selectively influences the shear capacity of the cushioning element.
[0031] In a preferred embodiment, the cushioning element
110 is provided, as shown in
Fig.i, as a midsole or a part of the midsole, respectively. The cushioning element
110 comprises randomly arranged particles of an expanded material. In an embodiment,
the whole cushioning element
110 consists of expanded material. Here, however, different expanded materials, or mixtures
of several different expanded materials, can be used in various partial regions of
the cushioning element
110. In a further embodiment, only one or more partial regions of the cushioning element
110 consist of expanded material, while the rest of the cushioning element
110 consists of non-expanded material. For example, a cushioning element
110 can comprise a central region of particles of one or more expanded materials, said
central region being surrounded by a frame of non-expanded material in order to increase
the form stability of the sole. By means of an appropriate combination of expanded
and/or non-expanded materials, a cushioning element
110 with the desired cushioning and stability properties can be manufactured.
[0032] The particles of the expanded material can, in particular, comprise one or more of
the following materials: expanded ethylene-vinyl-acetate (eEVA), expanded thermoplastic
urethane (eTPU), expanded polypropylene (ePP), expanded polyamide (ePA), expanded
polyether block amide (ePEBA), expanded polyoxymethylene (ePOM), expanded polystyrene
(PS), expanded polyethylene (ePE), expanded polyoxyethylene (ePOE), expanded ethylene
propylene diene monomer (eEPDM). Each of these materials has specific characteristic
properties which, depending on the requirement profile for the sole, can be advantageously
used for the manufacture of the shoe sole. In particular eTPU has excellent cushioning
properties which remain unchanged also at lower or higher temperatures. Furthermore,
eTPU is very elastic and restores the energy stored during compression, e.g. when
treading on the ground, almost entirely to the foot during subsequent expansion. On
the other hand, EVA, for example, distinguishes itself by great strength and is therefore
suitable, e.g., for the construction of a frame which surrounds regions of expanded
material or the whole cushioning element
110, so as to give the cushioning element
110 high form stability.
[0033] The use of various materials or mixtures of different materials for the manufacture
of the cushioning element
110 further allows for providing cushioning elements
110 comprising regions with different intrinsic shear resistances. In connection with
a control element
130, as described herein, this significantly increases the freedom of design in the construction
of shoe soles
100 and thereby the possibilities of selectively influencing the shear behavior of the
shoe sole
100.
[0034] In a preferred embodiment, the control element
130, as shown in
Fig. 1, is provided as an outsole or as a part of an outsole. The control element
130 here preferably comprises one or more of the following materials: rubber, non-expanded
thermoplastic urethane, textile materials, PEBA as well as foils or foil-like materials.
In a particularly advantageous embodiment, the cushioning element
110 and the control element
130 are manufactured from materials of a common material class, in particular expanded
and/or non-expanded thermoplastic urethane. This significantly simplifies the manufacturing
process, as, for example, the cushioning element
110 and the control element
130 can be provided as one integral piece in a single mold without additional use of
adhesives.
[0035] In order to selectively influence the shear behavior of the cushioning element
110, the control element has a number of protrusions
132 which are different in size, hardness and expansion, elevations or bulges
135 of different lengths, thicknesses and structures, as well as openings and recesses
138 with different diameters. By varying these design possibilities, the influence exerted
by the control element
130 on the shear behavior of the cushioning element
110 can be selectively controlled.
[0036] Figs. i6a-b, for example, show an embodiment
1600 of a sole
1610 according to the invention for a shoe which comprises a cushioning element
1630 provided as a midsole and which comprises randomly arranged particles
1635 of an expanded material.
Fig. 16a shows the unloaded state and
Fig. 16b shows the loaded state after touching
1650 the ground. The sole
1610 further comprises a control element
1620 provided as an outsole and which comprises a number of protrusions
1622 as well as a number of recesses/depressions
1628. Here, the material of the control element
1620 preferably has a higher strength/ stiffness than the material of the midsole
1630. For example, the control element
1620 can be provided as a foil onto which the protrusions
1622 can be selectively applied. For example, the control element
1620 can be a foil from TPU onto which protrusions
1622 also made from TPU can be applied. Such a preferred embodiment has the advantage
that the foil and the protrusions, for example, can enter into a chemical bond without
using additional bonding agents and which is extremely stable and resistant. In other
embodiments, the control element comprises other/additional materials.
[0037] As shown in
Fig. 16b, after touching
1650 the ground, the protrusions
1622 press into the material of the midsole
1630, since the material of the control element
1620, as already mentioned, is preferably of a higher stiffness/strength than the material
of the midsole
1630. Thereby, regions
1660 and
1670 are formed in which the material of the midsole
1630 is compressed to varying degrees.
[0038] In particular the material of the midsole in the regions
1670, in which the protrusions
1622 press under load into the midsole
1630, is compressed to a higher degree than in the regions
1660, in which the control element comprises recesses/depressions
1628. The different compressions of the midsole material caused thereby selectively influence
the stretching and/or shear capacity of the midsole material in the corresponding
regions
1660 and
1670. For example, the stretching capacity of the midsole material decreases in the further
compressed regions
1670 compared to the less compressed regions
1660. Furthermore, this leads to an anchoring of the midsole
1630 at the outsole
1620 and hence to an increased ground grip.
[0039] Thus, the stretching and/or shear capacity of the midsole
1630 can be selectively activated or suppressed in individual partial regions by means
of different designs of the control element
1620 with varied protrusions
1622.
[0040] The protrusions
1622 can be of varied design. For example, the protrusions
1622 can be pointed, cone-shaped or pyramid-shaped, the protrusions
1622 can be cylindrical, they can be hemispherical, the control element
1620 can be wave-like and so forth. The protrusions
1622 here serve as a kind of anchor points which allow for a targeted local compression
of the midsole material. Widely spaced protrusions
1622 here allow, for example, for greater stretching movements of the midsole materials
than closer spaced protrusions
1622. The shear capacity of the midsole
1630 can also be selectively influenced thereby.
[0041] Fig. 17 shows a particularly preferred embodiment
1700 of a sole
1710 according to the invention that comprises a cushioning element
1730 provided as a midsole and which comprises randomly arranged particles
1735 of an expanded material, in unloaded state. The sole
1710 further comprises a control element
1720 provided as an outsole, said control element comprising a number of protrusions
1722 and a number of recesses/depressions
1728. The material of the control element
1720 here preferably has a higher strength/stiffness than the material of the midsole
1730. The symmetrical, wave-like design of the control element shown in
Fig. 17 allows, on the one hand, a particularly good anchoring of the midsole
1730 to the outsole
1720 under load, as described above, and thus a particularly good ground grip. Furthermore,
a control element
1720 designed in such a way can be introduced without any problem into a mold used for
manufacture, during the manufacturing process.
[0042] Fig. 18 schematically shows further embodiments of control elements
1800a, 1800b, 1800c and
1800d according to the invention. The embodiments
1800a, 1800b, 1800c and
1800d, preferably provided as an outsole or parts thereof, comprise a number of protrusions
1810 as well as depressions and/or reinforcing elevations
1820 which can, for example, connect two protrusions to each other. Here, the protrusions
1810 can comprise a number of different shapes, sizes, heights, etc., as already discussed
above. The same applies to the depressions and/or reinforcing elevations
1820. For example, their width/thickness and/or depth/height as well as their position
and orientation on the control elements
1800a, 1800b, 1800c and
1800d can be adapted to the sole according to the respective requirements in order to selectively
influence the properties of the sole. Here, too, it is explicitly emphasized that
the depressions and/or reinforcing elevations
1820 need not perforce be arranged between two protrusions
1810, but serve as stand-alone possibilities to design control elements according to the
invention. In particular, such a reinforcing elevation can be advantageously used
in the medial midfoot region (cf.
1455) in order to increase the stability of the sole there and to reduce the shear and
stretching capacity of the midsole material in this region.
[0043] Furthermore, a control element can, according to a further aspect of the invention,
comprise additional functional elements, such as, e.g., a torsion- and/or reinforcing
element and the like, as a component and be manufactured as one integral piece therewith.
[0044] In addition, a control element can be provided as a complete outsole. In a further
embodiment, however, an outsole comprises a number of individual independent control
elements which may also be connected to each other.
[0045] In a preferred embodiment, the first region, which has a reduced shear capacity as
compared to the second region, is located in the medial region of the midfoot, while
the second region is located in the lateral region of the heel. In a particularly
preferred embodiment, the control element
130 comprises in particular a stabilizing bulge
135 at the medial edge of the midfoot region, as well as a number of openings with a
diameter increasing towards the heel and the tip of the foot. The shear behavior of
the cushioning element
110 adjusted in this way advantageously supports the natural physiological processes
in the movement apparatus of a runner and increases the wear comfort and the efficiency
of the runner, along with a minimization of the risk of injuries.
[0046] Besides influencing the shear behavior of the cushioning element
110, the control element can also influence the bending resistance of the cushioning element.
For example, if the control element
130 is firmly attached to the cushioning element
130 in a region, the bending resistance of the control element
130 also influences the bending resistance of the cushioning element
110. The bending resistance of the control element
130, for its part, depends, for example, on the above-mentioned design options of the
control element
130. So, in the preferred embodiment shown in
Fig. 1, the bending resistance in the heel and toe region is lower than in the midfoot region
which is stabilized by means of the reinforcing bulge
135.
[0047] In a further preferred embodiment, the sole
100 further comprises a decoupling region
160. In this region, the cushioning element
110 and the control element
130 are not directly connected to each other. In one embodiment, there is no connection
at all between the cushioning element
110 and the control element
130 in this region. In a preferred embodiment, the cushioning element
110 and the control element
130 are bonded in this region by means of a material which has a shear capacity. In a
particularly preferred embodiment, this material with shear capacity comprises, for
example, one or more of the following materials: eTPU, foamed material or a gel. This
enables a further shearing motion of the cushioning element
110 with respect to the control element
130 and thus an additional possibility of influencing the shear behavior of the sole
100. Such a decoupling region
160 is preferably located in the lateral heel region, since here, as will be shown further
below in greater detail, the strongest shear forces occur during running.
[0048] Fig. 19 shows a cross-section in medial-lateral direction through an embodiment of a midsole
1900 according to the present invention comprising randomly arranged particles
1910 of an expanded material and which can be advantageously combined with the other aspects
of the present invention described herein. In the embodiment shown in
Fig. 19, the whole midsole
1900 consists of expanded material. It is, however, clear to the skilled person that this
is merely a specific example of a midsole
1900 according to the invention, and that in other embodiments only one or more partial
regions of the midsole
1900 can comprise particles
1910 of expanded material. The midsole further comprises a first plate element
1920 and a second plate element
1930 that can slide relative to each other. Particularly preferred is a design in which
the plate elements
1920 and
1930 can perform a sliding movement in several directions. In a preferred embodiment,
the two plate elements
1920 and
1930 are completely surrounded by the material of the midsole
1900, particularly preferred by the expanded material
1910 of the midsole
1900. In other embodiments, however, the plate elements
1920 and
1930 are only partially surrounded by the material of the midsole
1900.
[0049] Preferably, the two plate elements
1920 and
1930 are arranged, as shown in
Fig. 19, in the heel region of the midsole
1900 such that they are located directly opposite each other. In a further embodiment,
there is a lubricant or a gel or the like between the two plate elements
1920 and
1930, which counteracts wear of the plate elements
1920,
1930 caused by the sliding movement and facilitates sliding.
[0050] By the sliding movement of the two plate elements
1920 and
1930, such an arrangement can, for example, absorb or reduce, respectively, the horizontal
shear forces acting on the movement apparatus of the wearer when he treads on the
ground. This prevents wear of the joints and injuries of the wearer, in particular
when he/she is running/walking fast. In other embodiments, the arrangement shown can
also be located in a different region of the midsole
1900, for example, in order to further support the rolling of the foot during a step.
[0051] In a further embodiment (not shown), the two plate elements
1920 and
1930 each comprise, in addition, a curved sliding surface. In a preferred embodiment,
the curvature of the two sliding surfaces is chosen such that the two sliding surfaces
match positively. By an appropriate selection of the degree and orientation of the
curvature, it is possible to influence in which direction the sliding movement of
the first plate element
1920 relative to the second plate element
1930 preferably takes place, for example, when treading on the ground. This, again, exerts
an influence on the shear forces which are absorbed by the midsole or passed on to
the wearer, respectively.
[0052] Further preferred embodiments of such plate elements which can slide relative to
each other and which can be advantageously combined with one or more of the embodiments
described herein that belong to the invention are to be found in
DE 102 44 433 B4 and
DE 102 44 435 B4.
[0053] For the functionality described just now it is further advantageous if the material
of the midsole
1900 counteracts the sliding movement of the two plate elements
1920 and
1930 by a restoring force. Preferably, this restoring force is due to the fact that the
two plate elements
1920 and
1930 are surrounded by the material of the midsole
1900, in particular the expanded material
1910 of the midsole
1900, and that the material of the midsole
1900 is compressed by the movement of the first and the second plate element
1920 and
1930, respectively, in the regions which are adjacent to the two plate elements
1920 and
1930 in the direction of the sliding movement. Due to the elastic properties of the material,
in particular of the expanded material
1910 of the midsole
1900, a restoring force is produced which counteracts the sliding movement of the first
and the second plate element
1920, 1930, respectively, with no need for complicated mechanics to this effect.
[0054] Fig. 20 shows a cross-section in medial-lateral direction of a variation of the embodiment
discussed just now with a midsole
2000, which comprises randomly arranged particles
2010 of expanded material. The midsole comprises a plate element
2020 and a second, sled-shaped element
2030. The two elements
2020,
2030 can perform a sliding movement relative to each other. Due to the sled-shaped design
of the second element
2030, a preferred direction for such a sliding movement is predetermined. In a preferred
embodiment, however, there are voids
2040 between the first element
2020 and the second, sled-shaped element
2030 which also allow for small sliding movements of the two elements
2030 and
2040 relative to each other and which do not lie in the preferred direction mentioned
above. By adapting the size of the voids
2030, the extent of such sliding movements which do not lie in the preferred direction
can be individually adapted to the needs and requirements of the sole. So, very small
voids
2040 allow for sliding movements of the two elements
2020 and
2030 almost exclusively in the preferred direction, which can lead to an increased stability
of the sole. Larger voids
2040, however, facilitate noticeable sliding movements also in a non-preferred direction.
This enables, for example, a better absorption of the horizontal shear forces by the
sole when contacting the ground.
[0055] In the preferred embodiment shown in
Fig. 1, the cushioning element
110 further surrounds an element
120 at least partially, for example, a torsion or reinforcing element. In a preferred
embodiment, the element
120 has higher deformation stiffness than the expanded material of the cushioning element
110. The element
120 hence can serve to further influence the elasticity- and also shear properties of
the sole
100. In a further embodiment, the element
120 can, for example, also be an element serving the optical design and/or an element
for receiving an electronic component and/or an electronic component or any other
functional element. In case the element
120 serves to receive a further element, such as, e.g., an electronic component, then
it has preferably a hollow region which is accessible from the outside. In the embodiment
shown in
Fig. 1, such a cavity could, e.g., be located in the region of the recess
140. I in a preferred embodiment, the element
120 is not bonded, for example by an adhesive bond, with the cushioning element
110. In particular, the element does not comprise, in a preferred embodiment, a bond with
the expanded material of the cushioning material
110. Since the cushioning element
110 partially surrounds the element, such a bond for fixing the element
120 is not required. Therefore, also non-glueable materials can be used for manufacturing
the shoe. In a further embodiment, the element
120 can also be connected/bonded with the control element
130 in individual regions, for example by means of a bond such as, e.g., an adhesive
bond, or be provided as one integral piece.
[0056] In the embodiment shown in
Fig. 1, the sole
100 further comprises a heel clip
150. Preferably, the heel clip
150 comprises a lateral finger and a medial finger which independent from each other
encompass the lateral and the medial side of the heel. This allows a good fixation
of the foot on the sole
100 without at the same time excessively restraining the room to move of the foot. In
a further preferred embodiment, the heel clip
150 further comprises a recess in the region of the Achilles' tendon. This prevents a
chafing or rubbing in particular of the upper edge of the heel clip
150 on the Achilles' tendon in the region above the heel. In a preferred embodiment,
the heel clip
150 can further, be bonded, e.g. by a bond, to the control element
130 and/or the element
120 or be provided together with this as one integral piece.
[0057] Fig. 2 shows four different shoes
200, 220, 240 and
260 which were used for taking measurements of elasticity and shear properties of soles
from various materials. The most important results of these measurements are summarized
in the following
Figs. 3a -
9.
[0058] The shoe
200 is a shoe with an upper
205 as well as a shoe sole
210 and a sliding element
212, such as described, for example, in
DE 102 44 433 B4 and
DE 102 44 435 B4.
[0059] The shoe
220 comprises an upper
225 as well as a midsole
230 from eTPU which is surrounded by a frame from EVA. The EVA can, for example, be a
compression molded 020 55C CMEVA which has a density of 0.2 g/cm^3 and a hardness
of 55asker C.
[0060] The shoe
240 comprises an upper
245 as well as a midsole
250 of EVA.
[0061] Furthermore, the shoe
260 comprises an upper
265 as well as a midsole
270 of eTPU.
[0062] Figs. 3a, 3b and
4 show the vertical (i.e. the direction from foot to ground) compression of the soles
of eTPU (shoe
260) and EVA (shoe
240).
[0063] For measuring these and further discussed properties of the various materials and
sole designs, for each measurement a large number (>100) of pictures, referred to
as "stages", were taken in the course of a step cycle. These are continuously numbered
starting from 1. For each measurement there is hence a one-to-one correspondence between
the number or "stage" of a take and the point in time of this take within the respective
step. However, it has to be noted that between different measurements there may be
a certain time offset for the individual stages, i.e. the stages with an identical
number from various measurements do not perforce correspond to the same point in time
during the step measured in the respective measurement.
[0064] Pictures
300a and
300b of
Figs. 3a and
3b were taken during the heel touching the ground.
Figs. 3a and
3b show the compression in percent of the respective midsole regions compared to the
unloaded state of the sole. As expected, no compression occurs in the forefoot region
(cf.
320a, 320b) while the ground is touched by the heel. In the heel region, however, noticeable
compressions are visible on the sole of eTPU (
cf.
310a). The measurements therefore show that eTPU yields significantly more strongly under
vertical load than EVA. Furthermore, the energy stored during compression of the eTPU
sole is essentially restored to the runner in the course of the step. This increases
the running efficiency significantly.
[0065] This is also confirmed by
Fig. 4. On the horizontal axis, the number of the respective stage, i.e. the time, is shown,
and on the vertical axis, the vertical compression of the midsole is shown. The measured
values
410 for a sole
270 from eTPU are shown as well as the measured values
420 for a sole
250 from EVA. At the time of the maximum vertical load, the EVA midsole
250 can be depressed only by about 1.3 mm, while the eTPU midsole
270 can be depressed by about 4.3 mm. Generally, the values of the vertical compression
for eTPU compared to those of EVA range from 2:1 to 3:1, in some embodiments even
above this.
[0066] Figs. 5a and
5b show the local material stretch of the midsole material compared to the unloaded
state of the sole within the lateral side wall of the eTPU midsole
270 (measurement
500a) and the EVA midsole
250 (measurement
500b), also at a moment when the heel touches the ground. In addition to a percent indication
of the material stretch compared to the unloaded state of the sole, the pictures of
Figs. 5a and
5b indicate, however, also the direction of the material stretch in the form of stretch
vectors. From the pictures, it can be seen that in the eTPU midsole
270, significantly greater material stretches occur than in the EVA midsole
250. This is due to the better shear capacity of eTPU compared to EVA. Therefore, eTPU
is particularly appropriate for manufacturing a cushioning element for absorbing shear
forces during running. In the example discussed here, the material stretch with eTPU
is 2 - 3 times higher than with EVA. More precisely, the material stretch of eTPU
is on average a stretch of 6-7%; the maximum stretch is 8-9%; the material stretch
for EVA is on average a stretch of 2%; the maximum stretch is 3-4%.
[0067] Furthermore, the measurements reveal that the material stretch in the lateral side
wall of the eTPU midsole
270 and of the EVA midsole
250 follow the natural shape of the metatarsal arch during running, i.e. the shoe follows
the rolling movement of the foot. This is advantageous for the wear comfort and fit
of the foot.
[0068] Figs. 6a-6c show the measurements
610a, 610b and
610c of the relative offset of two measurement points in millimeters, which are each located
at the opposite ends of the measurement sections
710a, 710b and
710c shown in
Figs. 7a -
7c. The measurements
610a 610b and
610c each comprise a complete step cycle. In
Figs. 7a-c, the shoes used for the respective measurements are shown in a starting position.
[0069] Figs. 6a, 7a show the measurement results and the measurement points for a shoe
200 with a shoe sole
210 and a sliding element
212, as described in
DE 102 44 433 B4 and
DE 102 44 435 B4.
[0070] Figs. 6b, 7b show the measurement results and the measurement points for a shoe
220 with a midsole
230 of eTPU and an EVA rim.
[0071] Figs. 6c, 7c show the measurement results and the measurement points for a shoe with an EVA sole
250.
[0072] It is clearly visible that the sliding element
212 of the shoe
200 and the eTPU sole with EVA rim
230 allow significantly greater offsets between the two measurement points than the EVA
midsole
250. This means a better shear capacity of the lower midsole surface relative to the upper
midsole surface and thus a better absorption capacity of the shear forces occurring
during running. It is to be noticed that the shoe
220 which is simpler in construction allows offset values of up to 2.5 mm (cf.
Fig. 6b), while the shoe
200 with the sliding element
212 allows only offset values of up to about 2 mm (cf.
Fig. 6a). The shoe
240 with EVA midsole
250, in contrast, allows only offset values of up to about 0.5 mm (cf.
Fig. 6c).
[0073] The
Figs. 8a - 8c show further measurements of the shear behavior of the shoe
200 with the sliding element
212 (measurement
800a), of the shoe
220 with eTPU midsole with EVA rim
230 (measurement
800b), and of the shoe
240 with EVA midsole
250 (measurement
800c). What is shown is the local offset of the sole material compared to the unloaded
state at a moment when the heel touches the ground.
[0074] It is clearly visible that the shoe
200 with the sliding element
212 and the shoe
220 with eTPU midsole with EVA rim
230 have a substantially higher shear capacity in the region of the heel than the shoe
240 with EVA midsole
250.
[0075] Fig. 9 again shows measurement results of measurements of the shearing in the midsole material
in longitudinal direction (AP direction) during a complete step cycle for four different
shoes.
[0076] The curve
910 shows again the measurement results of
Fig. 6a for the shoe
200 with the sliding element
212, with a maximum shearing of about 2 mm when the heel touches the ground. The curve
930 again shows the measurement results of
Fig. 6b for the shoe
220 with eTPU midsole with EVA rim
230 with a maximum shearing of about 2.5 mm during the touching of the ground by the
heel. The curve
940 again shows the measurement results of
Fig. 6c for the shoe
240 with EVA midsole
250 with a maximum shearing of about 0.5 mm during the impacting on the ground with the
heel. The curve
920, finally, shows the measurement results of a measurement carried out in the same way
for the shoe
260 with eTPU midsole
270 with a maximum shearing of about 1.8 mm during the touching of the ground by the
heel.
[0077] One can thus recognize that the shoe
260 with the eTPU midsole
270 and in particular the shoe
220 with eTPU midsole with the EVA rim
230 have a very good shear capacity and thus are principally well-suited for the construction
of midsoles.
[0078] Figs. 10a -
13d show further measurements of the shear capacity of differently designed soles.
[0079] Figs. 10a -
10d show measurements of the changes in length of measurement sections of which one is
arranged in longitudinal direction (AP direction) and one in medial-lateral direction
(ML direction) in the heel region of the sole during a step cycle. These changes in
length provide information on the plantar shear capacity of the respective sole.
[0080] Fig. 10a shows the change in length
1010a of the measurement section
1015a extending in AP direction, and the change in length
1020a of the measurement section
1025a, which extends in ML direction, for a shoe with an EVA midsole without outsole, as,
e.g., the shoe
240. The measurements indicate a maximum change in length of about 1.2 mm in AP direction
and of about 0.3 mm in ML direction.
[0081] Fig. 10b shows the change in length
1010b of the measurement section
1015b extending in AP direction and the change in length
1020b of the measurement section
1025b extending in ML direction for a shoe with an eTPU midsole without outsole, as, e.g.,
the shoe
260. The measurements show a maximum change in length of about 3.5 mm in AP direction
and of about 1.5 mm in ML direction.
[0082] Fig. 10c shows the change in length
1010c of the measurement section
1015c extending in AP direction and the change in length
1020c of the measurement section
1025c extending in ML direction for a shoe with a sliding element, as for instance the
shoe
200. The measurements show a maximum change in length of about 3.2 mm in AP direction
and of about 0.7 mm in ML direction.
[0083] Fig. 10d shows the change in length
1010d of the measurement section
1015d extending in AP direction and the change in length
1020d of the measurement section
1025d extending in ML direction for the preferred embodiment of a shoe
1400 according to
Figs. 1 and
14a -
14c comprising a midsole, which comprises eTPU, as well as a control element
1450 (cf. below) provided as an outsole. The measurement show a maximum change in length
of about 3.4 mm in AP direction and a negative change in length of about 0.5 mm in
ML direction. In particular the negative change in length in ML direction means a
very good stability of the shoe in the midfoot region which reflects the influence
of the medial reinforcement
1455 of the control element
1450.
[0084] Figs. 11 and
12 show the average values of a series of measurements conducted analogously to the
measurements shown in
Figs. 10a -
10d.
[0085] Fig. 11 shows the average change in length of the measurement section extending in AP direction
during a complete step cycle for a shoe with a sliding element, as, for example, the
shoe
200 (cf. curve
1110), for a shoe with an eTPU midsole, as, for example, the shoe
260 (cf. curve
1120), for a shoe with an EVA midsole, as, for example, the shoe
240 (cf. curve
1130) and for the shoe
1400 according to
Figs. 14a -
14c (cf. curve
1140).
[0086] Fig. 12 shows the average change in length of the measurement section extending in ML direction
during a complete step cycle for a shoe with a sliding element, as, for example, the
shoe
200 (cf. curve
1210), for a shoe with an eTPU midsole, as, for example, the shoe
260 (cf. curve
1120), for a shoe with an EVA midsole, as, for example, the shoe
240 (cf. curve
1230), and for the shoe
1400 according to
Figs. 14a -
14c (cf. curve
1240).
[0087] As can be inferred from
Figs. 11 and
12, the shoe
1400 according to a particularly preferred embodiment has, with a maximum change in length
in AP direction of more than 3 mm, the best shear capacity of all four tested shoe
types. At the same time, the shoe
1400 shows a sufficient stability in ML direction, as can be seen from
Fig. 12. As shear forces occur during running mainly in AP direction, and since a bending/slipping
of the foot in ML direction is to be avoided as far as possible, this combination
of properties of the shoe is particularly advantageous.
[0088] In further preferred embodiments, the cushioning element enables a shearing motion
in AP direction of a lower sole surface relative to an upper sole surface of more
than 1 mm, preferably more than 1.5 mm and particularly preferably more than 2 mm.
A selection between different values of the shear capacity of the cushioning element
enables to adapt the shoe sole individually to the needs and physiological conditions
of a runner. The values discussed here serve the skilled person only as a guideline
in order to obtain an impression of typical preferred values of the shear capacity
of a cushioning element. In individual cases, these values ideally have to be specifically
adapted to the wishes and needs of the wearer.
[0089] Figs. 13a -
13d show the plantar material stretch in the sole of various shoes in percentages, compared
to the unloaded state of the shoe, at the moment when the foot is pushed off the ground
via the forefoot, as schematically shown in
Fig. 13e. Figs. 13a -
13d furthermore show the stretch vectors which locally indicate the direction of the
material stretch.
Fig. 13a shows a measurement
1300a for a shoe
240 with an EVA midsole,
Fig. 13b shows a measurement
1300b for a shoe
260 with an eTPU midsole.
Fig. 13c shows a measurement
1300c for a shoe with a sliding element, as, for example, the shoe
200, and
Fig. 13d shows a measurement
1300d for the preferred embodiment of a shoe
1400 according to
Figs. 1 and
14a -
14c, which comprises a midsole comprising eTPU, as well as a control element
1450 provided as an outsole (cf. below).
[0090] As can clearly be seen from the figures, in this position of the foot/shoe (i.e.
when pushing the foot off the ground over the forefoot region, cf.
Fig. 13e) the main load and deformation of the material of the shoes
240 and
260 occurs locally in the middle of the forefoot region (cf.
Fig. 13a and
Fig. 13b) (in other positions of the foot, the main load and deformation can also be observed
in the heel region). In the case of the shoe with the sliding element and the shoe
1400, however, the material stretches follow the shape of the outsole. In
Fig. 13d, in particular, the structure of the outsole
1450 with its openings
1452, elevations
1458 and protrusions
1459 can be seen. Furthermore,
Fig. 13d shows that almost all of the stretch vectors in the forefoot region extend parallel
in AP direction, i.e. the material stretches almost exclusively in AP direction, while
it shows a good stability in ML direction. This is desirable for a dynamic push-off
of the foot without losing stability. In case of insufficient stability of the sole
in ML direction, the foot would otherwise be in danger of slipping sideways or bending,
in particular at a higher running speed and, for instance, in a curve or on uneven
terrain.
[0091] The control element
1450, e.g. in the form of an outsole, contributes to forming predefined zones where a specific
shearing- and/or stretching behavior or a specific stability is required. The design
of the control element
1450 can be adapted to the requirements of each sport. Linear sports have different requirements
concerning the shearing behavior and stability of the sole than, for example, lateral
sports. Therefore, the control elements
1450 and sole concepts can be individually designed for specific sports. For example,
for sports like (indoor) football, basketball, or running sports, the best/most important
shearing and stability zones can be determined and individually adapted. For example,
in many fields of application, such preferred shearing and/or stretching zones are
located beneath the big toe and in the heel region. Furthermore, by means of the aspects
pertaining to the invention which are described herein, soles can be manufactured
which can ideally imitate the rolling of the foot like when walking barefoot.
[0092] Figs. 14a -
14c show a preferred embodiment of a shoe
1400 with a cushioning element
1410 provided partially as a part of a midsole or as a midsole, said cushioning element
comprising randomly arranged particles of expanded material, in particular particles
of eTPU, and a control element
1450 provided as part of an outsole or as an outsole, which reduces the shear capacity
of the midsole
1410 in the medial region of the midfoot compared to the lateral region of the heel. In
addition, the shoe shown in
Figs. 14a -
14 comprises an upper
1420. In a preferred embodiment, the shoe
1400 further comprises a heel clip
1430 as well as an additional torsion or stiffening element
1440, as already discussed above in connection with
Fig. 1 and the corresponding embodiments.
[0093] In one preferred embodiment, the control element
1450 which is provided as an outsole does not comprise expanded material. Particularly
preferred is the control element made from rubber, thermoplastic urethane, textile
materials, PEBA or foils and foil-like materials or a combination of such materials,
respectively. It is furthermore advantageous if the control element
1450 and the cushioning element
1410 are manufactured from materials from a common class of materials, as already mentioned
above. Furthermore, the control element
1450 preferably comprises a number of openings
1452 of different sizes, a bulge
1455 in the medial region of the midfoot as well as a number of elevations
1458 and protrusions
1459. These elements serve, as already discussed, to influence the flexibility and stiffness
properties of the control element
1450, which, for their part, influence the shear capacity and the bending stiffness of
the sole and particularly the midsole
1410. The protrusions
1459 and the elevations
1458 can, furthermore, increase the ground grip, in particular, since the control element
1450 in the present preferred embodiment is provided as a part of an outsole.
[0094] The preferred embodiment shown in
Figs. 14a -
14c, with a bulge
1455 in the medial region of the midfoot as well as a number of openings
1452 of varying diameter, enables a particularly good shear capacity in the heel region,
especially in the lateral heel region, as well as a good stability in the medial midfoot
region. As already mentioned several times, this combination of properties is particularly
advantageous for use in case of running shoes. Other combinations of properties are,
however, also possible, and the design options and embodiments presented herein enable
the skilled person to manufacture a shoe having the desired properties.
[0095] Figs. 15a -
15c show a further preferred embodiment of a shoe
1500 according to an aspect of the present invention. The shoe
1500 comprises a cushioning element
1510 provided as a part of a midsole or as a midsole which comprises randomly arranged
particles of expanded material, for example eTPU. Furthermore, the shoe
1500 comprises a control element
1540 provided as a part of an outsole or as an outsole which can selectively influence
the shear capacity and the bending stiffness of the cushioning element
1510 in the way which was already repeatedly discussed. The shoe further comprises an
upper
1520 as well as a heel clip
1530.
[0096] Figs. 21a-b show another preferred embodiment of a shoe
2100 according to the invention. The shoe
2100 comprises a sole comprising a cushioning element
2110 with randomly arranged particles of an expanded material. In the exemplary embodiment
shown here, the cushioning element
2110 is provided as a midsole
2110. It may, however, also be merely a part thereof, for example.
[0097] The shoe
2100 furthermore comprises an upper
2120. The upper
2120 may be made from a large variety of materials and by a large variety of manufacturing
methods. The upper
2120 can, in particular, be warp-knitted, weft-knitted, woven or braided, and it can comprise
natural or synthetic materials, it may comprise fibers or yarns, multilaminate materials,
compound materials and so on.
[0098] The sole of the shoe
2100 furthermore comprises a control element
2150, provided in the case at hand as an outsole
2150. In other cases it may only be part of an outsole or it may be part of the midsole.
The control element
2150 is free from expanded material. Suitable materials for the control element/outsole
2150 may include rubber, non-expanded thermoplastic urethane, textile materials, PEBA
as well as foils and foil-like materials.
[0099] The control element
2150 reduces shearing motions within a first region of the cushioning element
2110 compared to shearing motions within a second region of the cushioning element
2110. Reduced shearing may, for example, occur in regions
2160, 2165 where the control element
2150 comprises continuous regions of material. It may also occur in the regions of the
"material webs"
2170, 2175, which are interspersed by holes
2152, 2155, 2158 in the control element
2150. In the regions of these holes
2152, 2155, 2158, for example, the shearing motion maybe increased in comparison.
[0100] Taking account of the explanations regarding the inventive concept of controlling
the shearing motion of a cushioning element as described in this document, it is clear
to a skilled person that by choosing different designs and arrangements of the continuous
material regions (like regions
2160, 2165), the "material webs" (like web
2170) and the holes (like holes
2152, 2155, 2158), the shearing and other properties, like e.g. the bending stiffness, torsional stiffness
or the general roll-off behavior, of the midsole
2110 of the shoe
2100 can be influenced as desired in a large number of ways. The influence can be fine-tuned
even further with the potential inclusion of bulges, elevations, protrusions in the
control element
2150, as already described before.
[0101] In the present case, the control element
2150 is laser-cut from a blank (not shown). This may be done before the control element
2150 is affixed to the remaining parts of the sole of the shoe
2100, in particular the midsole
2110, and is preferably done in an automated manner, at least to a large degree. In principle,
however, the blank may also be arranged at, e.g., the midsole
2110 first, then the blank is cut and finally the cut-out sections of the blank are removed.
To this end, a bonding agent may be applied between the midsole
2110 and the blank, which does not immediately harden completely but still provides enough
adhesion that the blank is secured on the midsole
2110 (or other parts of the shoe
2100) for it to be cut. For cutting, the shoe
2100 including the blank may e.g. be arranged on a last to allow three-dimensional positioning
within a cutting device. After removal of the cut-out pieces of the blank, which is
still possible since the agent has not completely hardened, the bonding agent may
then be left to harden completely or this may be facilitated by heating, cooling,
energizing or other means.
[0102] In the simplest form, the blank may be provided as a material layer comprising, for
example, one or more of the materials suitable for the manufacture of a control element/outsole
mentioned above. It is also possible, for example, that the blanks are provided in
different sizes, thickness, with predefined holes, bulges, elevations, protrusions
and so forth, which may already provide a basic pattern that may then be fine-tuned
by the laser-cutting process. Such a basic pattern may, e.g., be adapted to specific
movement patterns occurring during, say, a specific sporting activity and different
blanks may be used for the manufacture of shoes
2100 for the different sporting activities. Examples may include blanks for running shoes,
tennis shoes, basketball shoes, football shoes, etc. This approach can have the advantage
that the blanks can be produced quickly and in a large number beforehand and the individual
customization can then be carried out more efficiently and more quickly. To this end,
the blanks may also already comprise the general outline of a foot or sole.
[0103] This can, in particular, become important, if the customization, particularly by
laser-cutting, is done on the spot, for example in a sales room, a sales stand at
a sporting event or he like, where the is only limited room for a cutting device and
manufacturing apparatus.
[0104] Laser-cutting the control element
2150 can provide for a large freedom in design for the control element
2150. It can also provide for the opportunity of an individual customization of the control
element
2150, sole and shoe
2100, as already mentioned. It may, for example, allow for numerous fashion designs and
a corresponding individualization of each sole or shoe
2100. The customization maybe sport specific or according to typical movements of a customer
or otherwise customer related. Furthermore, the laser-cutting may be automated to
a large degree and maybe based on, e.g., online tools or other ordering methods.
[0105] While reference has been made to laser cutting throughout the description of
Figs. 21a-b, other techniques are in principle also possible. Examples are CNC cutting, die cutting,
water jet cutting.
[0106] Finally,
Figs. 22a-d show further currently preferred embodiments of shoes
2200a, 2200b, 2200C, and
2200d according to the invention.
[0107] The main purpose of
Figs. 22a-d is to give the skilled person a better understanding of the scope and further possible
embodiments of the present invention. Therefore, the embodiments
2200a, 2200b, 2200C, and
2200d will only be discussed briefly. For a more detailed discussion of individual aspects,
reference is made to the discussion of the embodiments of shoes, soles, midsoles,
cushioning elements and control elements according to the invention already put forth
herein, in particular the discussion of the embodiments
100, 1400, 1500, 1600, 1700, 1800a-d, 1900, 2000 and
2100. The features, options and functionality discussed in relation to these embodiments
also apply to the embodiments
2200a, 2200b, 2200C, and
2200d, as far as applicable.
[0108] The shoes
2200a, 2200b, 2200C, 2200d each have a sole comprising a respective cushioning element
2210a, 2210b, 2210c and
2210d comprising randomly arranged particles of an expanded material. Whereas the cushioning
elements
2210a and
2210b of the shoes
2200a and
2200b only extend throughout the forefoot regions, the cushioning elements
2210c and
2210d of the shoes
2200c and
2200d extend throughout the entire soles of the shoes
2200C, 2200d. The cushioning elements
2210a, 2210b, 2210c and
2210d shown here are provided as part of a respective midsole. Other arrangements of the
cushioning elements are, however, also conceivable.
[0109] The soles of the shoes
2200a, 2200b, 2200c and
2200d furthermore each comprise a control element
2250a, 2250b, 2250c and
2250d free from expanded material. The control elements
2250a, 2250b, 2250c and
2250d each reduce shearing motions within a first region of the respective cushioning element
2210a, 2210b, 2210e and
2210d compared to shearing motions within a second region of the respective cushioning
element
2210a, 2210b, 2210c and
2210d. In the embodiments
2200a, 2200b, 2200c and
2200d shown here, the control elements
2250a, 2250b, 2250c and
2250d are provided as part of a respective outsole.
[0110] The control elements
2250a, 2250b, 2250c and
2250d may further serve the purpose to selectively increase the bending resistance of the
respective cushioning element
2210a, 2210b, 2210c and
2210d.
[0111] To influence the shearing motions and bending stiffness of the respective cushioning
elements
2210a, 2210b, 2210c, 2210d or soles, the control elements
2250a, 2250b, 2250c and
2250d comprise a number of holes or openings
2252a, 2252b, 2252c, 2252d in different arrangements, shapes, sizes, sole regions, etc.. The control elements
2250a, 2250b, 2250c and
2250d further comprise a "web" or material mesh
2258a, 2258b, 2258c, 2258d between the individual openings
2252a, 2252b, 2252c, 2252d.
[0112] Whereas the openings
2252a, 2252b, 2252c and material meshes
2258a, 2258b, 2258c are configured in a diamond shape in the embodiments
2200a, 2200b and
2200C, the openings
2252d and material mesh
2258d roughly form parallelograms. Other configurations are, however, also possible, as
already discussed at various times throughout this document and as shown, e.g., in
the heel region of the shoe
2200d. Moreover, the control elements
2250a, 2250b, 2250c and
2250d may also comprise further protrusions, elevations, etc.. For example, as shown in
Fig. 22a, the control element
2250a comprises a number of protrusions
2259a.
[0113] The recurring arrangement of the openings
2252a, 2252b, 2252c, 2252d and material meshes
2258a, 2258b, 2258c, 2258d in diamond or parallelogram shape may in particular result in one or more preferred
directions along which the soles may predominantly shear or bend. By the exact patterns
and arrangement of the holes and material regions, these preferred directions can
be adjusted to a given requirement profile for a particular sole or shoe.
[0114] In the following, further examples are described to facilitate the understanding
of the invention:
- 1. Sole for a shoe, in particular a sports shoe, comprising:
- a. a cushioning element comprising randomly arranged particles of an expanded material,
- b. a control element free from expanded material,
- c. wherein the control element reduces shearing motions within a first region of the
cushioning element compared to shearing motions within a second region of the cushioning
element.
- 2. Sole according to example 1, wherein the particles of expanded material comprise
one or more of the following materials: expanded ethylene-vinyl-acetate, expanded
thermoplastic urethane, expanded polypropylene, expanded polyamide, expanded polyether
block amide, expanded polyoxymethylene, expanded polystyrene, expanded polyethylene,
expanded polyoxyethylene, expanded ethylene propylene diene monomer.
- 3. Sole according to one of the preceding examples 1-2, wherein the control element
comprises one or more of the following materials: rubber, thermoplastic urethane,
textile materials, polyether block amide, foils or foil-like materials.
- 4. Sole according to one of the preceding examples 1-3, wherein the first region of
the cushioning element has a larger intrinsic shear resistance than the second region
of the cushioning element.
- 5. Sole according to one of the preceding examples 1-4, wherein the control element
has a larger thickness and/or fewer holes in a first control region controlling the
shearing motion of the cushioning element in the first region than in a second control
region controlling the shearing motion of the cushioning element in the second region.
- 6. Sole according to one of the preceding examples 1-5, wherein the cushioning element
is provided as a part of a midsole.
- 7. Sole according to example 6, wherein the control element is provided as a part
of an outsole.
- 8. Sole according to example 7, wherein the outsole comprises a decoupling region
that is not directly attached to the second region of the cushioning element of the
midsole.
- 9. Sole according to one of the preceding examples 1-8, wherein the control element
and the cushioning element are manufactured from a common class of materials, in particular
thermoplastic urethane.
- 10. Sole according to one of the preceding examples 1-9, wherein the first region
is located in the medial midfoot region and wherein the second region is located in
the lateral heel region.
- 11. Sole according to one of the preceding examples 1 - 10, wherein the control element
further increases the bending resistance of the cushioning element in the first region
compared to the second region.
- 12. Sole according to one of the preceding examples 1 - 11, further comprising a frame
made from non-expanded material, in particular ethylene-vinyl-acetate, surrounding
at least a part of the cushioning element.
- 13. Sole according to one of the preceding examples 1 - 12, wherein the cushioning
element allows for a shearing motion in longitudinal direction of a lower sole surface
relative to an upper sole surface of more than 1 mm, preferably more than 1.5 mm,
and particularly preferably more than 2 mm.
- 14. Sole according to one of the preceding examples 1 - 13, wherein the control element
is laser-cut from a blank.
- 15. Shoe, in particular a sports shoe, with a sole according to one of the preceding
examples 1 - 14.
- 16. Sole for a shoe, in particular a sports shoe, comprising:
- a. a midsole comprising particles of an expanded material; and
- b. an outsole comprising a number of protrusions as well as a number of recesses and/or
depressions,
- c. wherein the stretching capacity of the midsole is selectively activated or suppressed
in individual regions of the midsole by the shape and arrangement of the protrusions
and recesses/ depressions.
- 17. Sole according to example 16, wherein the material of the outsole has a higher
stiffness than the material of the midsole.
- 18. Sole according to one of examples 16 - 17, wherein the material of the midsole
is compressed to a higher degree in regions of the midsole in which protrusions press
into the midsole under a load on the sole, compared to the regions of the midsole
where the outsole comprises recesses and/or depressions.
- 19. Sole according to example 18, wherein the different compression of the midsole
material in different midsole regions influences the stretching capacity of the midsole
material in the corresponding regions.
- 20. Sole according to example 19, wherein the stretching capacity decreases in the
regions where the midsole material is more strongly compressed.
- 21. Sole according to one of examples 16 - 20, wherein widely spaced protrusions allow
for greater stretching movements of the midsole material than more closely spaced
protrusions.
- 22. Sole according to one of examples 16 - 21, wherein the outsole has a symmetrical,
wave-like shape.
- 23. Sole according to one of examples 16 - 22, wherein the protrusions are provided
as a material web or part of a material web, and wherein the recesses are provided
as openings in the web.
- 24. Sole according to one of examples 16 - 23, wherein the protrusions being pressed
into the midsole material under a load on the sole provides for an anchoring of the
midsole at the outsole to increase the grip of the sole on the ground.
- 25. Sole according to one of examples 16 - 24, further comprising a frame element
made of or comprising ethylene vinyl acetate, preferably wherein the frame element
surrounds the midsole region with the expanded material to increase the stability
of the midsole region with the expanded material.
- 26. Sole according to one of examples 16 - 25, wherein the bending stiffness and/or
torsional stiffens and/or roll-off behavior of the midsole is also at least partly
controlled by the shape and arrangement of the protrusions and recesses/depressions
of the outsole.
- 27. Sole according to one of examples 16 - 26, wherein the particles of the expanded
material are randomly arranged.
- 28. Sole according to one of examples 16 - 27, wherein the expanded material comprises
one or more of the following materials: expanded ethylene-vinyl-acetate, expanded
thermoplastic urethane, expanded polypropylene, expanded polyamide, expanded polyether
block amide, expanded polyoxymethylene, expanded polystyrene, expanded polyethylene,
expanded polyoxyethylene, expanded ethylene propylene diene monomer.
- 29. Sole according to one of examples 16 - 28, wherein the outsole comprises one or
more of the following materials: rubber, non-expanded thermoplastic urethane, textile
materials, PEBA, a foil, a foil-like material.
- 30. Shoe, in particular sports shoe, comprising a sole according to one of examples
16 - 29.