U.S. patent application number 13/058435 was filed with the patent office on 2011-06-30 for air-ventilated shoe sole.
This patent application is currently assigned to MASAI MARKETING & TRADING AG. Invention is credited to Hermann Oberschneider.
Application Number | 20110154693 13/058435 |
Document ID | / |
Family ID | 40289342 |
Filed Date | 2011-06-30 |
United States Patent
Application |
20110154693 |
Kind Code |
A1 |
Oberschneider; Hermann |
June 30, 2011 |
AIR-VENTILATED SHOE SOLE
Abstract
A mid-sole body has air inlet openings in the heel section and
air outlet openings in the midfoot section and/or ball/toe section.
The air inlet openings are connected to the air outlet openings via
a ventilation channel. The ventilation channel is covered by a
cover which is elastically resilient in the direction of the
outsole during walking when under strain. The shoe is
force-ventilated due to the rolling off of the shoe having such a
shoe sole during walking and heat is removed from the shoe
sole.
Inventors: |
Oberschneider; Hermann;
(Romanshorn, CH) |
Assignee: |
MASAI MARKETING & TRADING
AG
WINTERTHUR
CH
|
Family ID: |
40289342 |
Appl. No.: |
13/058435 |
Filed: |
August 17, 2009 |
PCT Filed: |
August 17, 2009 |
PCT NO: |
PCT/EP09/05959 |
371 Date: |
March 10, 2011 |
Current U.S.
Class: |
36/3B ;
36/25R |
Current CPC
Class: |
A43B 13/145 20130101;
A43B 7/08 20130101; A43B 13/026 20130101; A43B 17/08 20130101; A43B
13/12 20130101; A43B 1/04 20130101 |
Class at
Publication: |
36/3.B ;
36/25.R |
International
Class: |
A43B 7/06 20060101
A43B007/06; A43B 13/14 20060101 A43B013/14 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 21, 2008 |
EP |
08014825.7 |
Claims
1-13. (canceled)
14. A shoe sole with a midsole, having a midsole body extending
over a heel region, a midfoot region and a ball/toe region, and
with an outsole, wherein the midsole body has at least one air
inlet opening in the heel region, air outlet openings in the
midfoot region and/or the ball/toe region, and also a ventilation
channel, which connects the air inlet opening to the air outlet
openings and is covered on the side facing away from the outsole by
means of a cover, which is elastically compliant, in the direction
of the outsole, when under load during walking.
15. The shoe sole as claimed in claim 14, wherein, in a rear
portion, seen in the walking direction, of the heel region there is
a respective air inlet opening both on the outer side and on the
inner side, and in the midfoot region and/or the ball/toe region
there are air outlet openings both on the outer side and on the
inner side.
16. The shoe sole as claimed in claim 15, wherein the ventilation
channel has in the heel region a V-shaped heel portion, leading
with its legs to the air inlet openings, and in the midfoot region
and possibly the ball/toe region has a distributor portion, which
adjoins the heel portion and has a central main channel portion and
branch channel portions, branching off laterally from the latter
and leading to the air outlet openings.
17. The shoe sole as claimed in claim 14, wherein the ventilation
channel has two main channel portions, running at least
approximately in the longitudinal direction of the shoe sole and
connected to the air inlet openings, branch channel portions
branching off from one of the main channel portions to the outer
air outlet openings and from the other of the main channel portions
to the inner air outlet openings.
18. The shoe sole as claimed in claim 14, wherein the cover has an
insole, which has a carrier layer and, on the side of the carrier
layer that is facing the midsole body, an elastically compliant
supporting layer.
19. The shoe sole as claimed in claim 18, wherein the supporting
layer has a multiplicity of supporting elements arranged at a
distance from one another, protruding from the carrier layer and
supported on the midsole.
20. The shoe sole as claimed in claim 18, wherein the supporting
layer has a multiplicity of wave-shaped supporting strips,
protruding from the carrier layer and supported on the midsole.
21. The shoe sole as claimed in claim 18, wherein the supporting
layer has a knitted spacer fabric, which is supported on the
midsole.
22. The shoe sole as claimed in claim 14, wherein a soft heel part
is arranged in a heel recess of the midsole body, the outsole, in
the unloaded state, is kept in a form in which it is rounded in a
convex manner in the longitudinal direction of the shoe sole by the
midsole body and the soft heel part, and the midsole has in the
heel region and in the midfoot region a reinforcing element with
such a stability that the midsole is at least approximately
flexurally rigid, with respect to loads during standing and
walking, in its portion located above the soft heel part.
23. The shoe sole as claimed in claim 22, wherein the reinforcing
element is integrated in the midsole body and has a channel-like
recess for the ventilation channel.
24. The shoe sole as claimed in claim 17, wherein, in the
transverse direction of the shoe sole, the reinforcing element in
the midsole body is arranged in a central region and one of the
main channel portions runs on each side of the reinforcing
element.
25. The shoe sole as claimed in claim 24, wherein a ventilation
insert element, which is preferably U-shaped in plan view, is
integrated in the midsole body, delimits the main channel portions
with a cross-sectionally U-shaped channel wall and has air inlet
tube stubs, which protrude from the channel wall in the heel region
and are flow-connected to the main channel portions, and air outlet
tube stubs, which protrude from the channel wall in the midfoot
region and/or the ball/toe region and are flow-connected to the
main channel portions.
26. A walking device with a shoe sole as claimed in claim 14 and an
upper arranged on the shoe sole.
Description
[0001] The present invention relates to a shoe sole according to
the preamble of patent claim 1 and to a walking device with a shoe
sole according to claim 13.
[0002] A special shoe sole structure for walking devices is known
by the name "Masai Barefoot Technology", MBT for short, and also
known under the Swiss Masai label. A characteristic feature of the
MBT is a form of sole that is rounded convexly in the walking
direction, with an inserted soft heel part, known as the "Masai
sensor". The midsole has a reinforcing element--known as a
"shank"--integrated in it, which reinforces the midsole in such a
way that it is substantially flexurally rigid even in the portion
thereof that is above the soft heel part. The shoe sole structure
of the MBT walking device, deliberately soft and made to act in a
destabilizing manner for this reason, means that the foot loses the
hold and support that is characteristic of physiological
locomotion. This has an impact on major parts of the postural and
supporting musculature, because the body must now be actively kept
in balance. On account of these constantly required minimal
compensating movements and adaptations of the musculature of the
foot in seeking to maintain a stable standing position, wearing MBT
walking devices achieves the effect of performing a kind of
permanent coordination training and works additional parts of the
musculature of the skeleton. In particular, neglected muscles are
trained, posture and gait pattern are improved and the body is
toned and shaped. Furthermore, wearing MBT walking devices can
alleviate back, hip, leg and foot ailments and joint, muscle,
ligament or tendon injuries as well as relieve hip and knee joints.
On the one hand, the MBT walking device leads to improved blood
circulation, and consequently to the foot being heated up, and, on
the other hand, the shoe sole has a considerable thickness, with
correspondingly good thermal insulating properties. There is
therefore a need to provide a shoe sole that is better able to
remove heat.
[0003] There is also the same need for shoe soles of a different
structure, in particular shoe soles for sport shoes. For example,
shoes of the "ClimaCool" series from the Adidas company have air
openings on the sole.
[0004] An object of the present invention is to provide a shoe sole
that has improved heat removal properties.
[0005] This object is achieved by a shoe sole that has the features
of patent claim 1.
[0006] A midsole body has at least one air inlet opening in the
heel region, and air outlet openings in the midfoot region and/or
in the ball/toe region. The air inlet opening and the air outlet
openings are connected to one another by means of a ventilation
channel. This is covered by a cover on the side of the midsole body
that is facing away from the outsole--on the upper side of said
midsole body. This cover is elastically compliant, in the direction
of the outsole, when under load during walking. Since the cover is
elastic, it returns to its original form again when the load is
relieved.
[0007] Consequently, the rolling motion during walking inevitably
causes a constant exchange of air in the shoe sole, which leads to
improved heat dissipation. The air ventilation thereby enforced has
the effect that air enters the shoe sole through the air inlet
opening and leaves again at the air outlet openings, which
counteracts a buildup of heated air under the foot.
[0008] The heated air in the ventilation channel is forced through
the air outlet openings by the compression of the sole, or the
cover thereof, when the heel is put down, in a way corresponding to
the subsequent rolling motion. In the course of the rolling motion,
the heel region is relieved of load, which leads to fresh air being
sucked into the ventilation channel through the air inlet opening.
A rolling motion that is optimal for this purely mechanical
principle, and associated optimal air ventilation, are achieved
with shoe soles according to claim 9. With conventional shoe soles,
it is unlikely that such efficient air ventilation can be
achieved.
[0009] Further preferred embodiments of the shoe sole according to
the invention are specified in the further dependent patent
claims.
[0010] The invention is explained in more detail on the basis of
exemplary embodiments that are represented in the drawing, in which
purely schematically:
[0011] FIG. 1 shows a plan view of a midsole body of a shoe sole
according to the invention, with two air inlet openings in the heel
region, which are flow-connected by way of a ventilation channel to
inner and outer air outlet openings in the midfoot region and in
the ball/toe region;
[0012] FIG. 2 shows a side view of a shoe sole according to the
invention, with air inlet openings and air outlet openings that are
formed on the midsole body and extend in the direction of the
outsole, the midsole body having a heel recess in which a soft heel
part is arranged;
[0013] FIG. 3 likewise shows a side view of a further embodiment of
a shoe sole according to the invention, likewise with a soft heel
part arranged in a heel recess of the midsole body, and air inlet
and air outlet openings, which however are arranged in an upper
peripheral region of the midsole body;
[0014] FIG. 4 shows a perspective representation of a preferred
embodiment of a cover for the ventilation channel, with an
air-permeable carrier layer and double-conical elastic supporting
elements protruding from the latter;
[0015] FIG. 5 shows, in a representation identical to that of FIG.
4, a further preferred embodiment of the cover, which likewise has
an air-permeable carrier layer, from which however elastically
deformable wave-shaped supporting strips protrude;
[0016] FIG. 6 shows, in a representation identical to that in FIGS.
4 and 5, a further particularly preferred embodiment of the cover,
with an air-permeable carrier layer and a supporting layer formed
as a knitted spacer fabric;
[0017] FIG. 7 shows an exploded representation of a possible
embodiment of the shoe sole according to FIG. 2;
[0018] FIG. 8 shows a side view of a further possible embodiment of
the shoe sole according to FIG. 2;
[0019] FIG. 9 shows a plan view of the shoe sole according to FIG.
8, the midsole body being transparent and the ventilation channel
being shown colored gray; and
[0020] FIG. 10 shows a perspective representation of a reinforcing
element of the embodiment according to FIGS. 8 and 9.
[0021] FIG. 1 shows a plan view of a midsole body 10 of a midsole
12. It has in a rear portion 14, seen in the walking direction L,
of a heel region 16 a respective air inlet opening 22 both on the
shoe sole inner side 18 and on the shoe sole outer side 20. The
shoe sole inner side 18 should be understood as meaning the side
facing the other shoe sole of a pair and the shoe sole outer side
20 should be understood as meaning the side of the shoe sole facing
away therefrom.
[0022] Furthermore, the midsole body 10 has in a midfoot region 24
and in a ball/toe region 26 in each case five air outlet openings
28, both on the shoe sole inner side and on the shoe sole outer
side. Seen in the walking direction L, the midfoot region 24
adjoins the heel region 16 and the ball/toe region 26 adjoins the
midfoot region 24, each of these regions extending approximately
over one third of the length of the shoe sole.
[0023] The air inlet openings 22 and the air outlet openings 28 are
connected to one another by way of a ventilation channel 30 formed
by a depression in the midsole body 10. This channel has in the
heel region 16 a heel portion 32 with two legs 34 arranged in a
V-shaped manner. Each of these legs 34 leads to one of the two air
inlet openings 22. Adjoining the heel portion 32, the ventilation
channel 30 has a distributor portion 36, the main channel portion
38 of which, flow-connected to the legs 34 of the heel portion 32,
runs up to the ball/toe region 26, in the longitudinal direction of
the shoe S. Seen in the direction at right angles to the
longitudinal direction of the shoe S, the main channel portion 38
is offset with respect to the longitudinal center of the shoe in
the direction of the shoe sole inner side 18, to run under the
inner instep.
[0024] Branch channel portions 40 branch off from both sides of the
main channel portion 38, each of these branch channel portions 40
running to one of the air outlet openings 28.
[0025] Both the air inlet openings 22 and the air outlet openings
28 have a width of preferably at least 4 mm and a length that is
preferably at least twice the stated width. Correspondingly, the
ventilation channel 30 also has, measured in a direction at right
angles to the upper surface 42, on the footbed side, of the midsole
body 10, with respect to said surface a depth of preferably at
least 4 mm. The width of the ventilation channel 30 is preferably
greater everywhere than the depth, preferably at least twice as
great.
[0026] On the side of the surface 42, the ventilation channel 30 is
covered by an elastically compliant cover 52, which is not shown in
FIG. 1 but preferred embodiments of which are described in
connection with FIGS. 4 to 6.
[0027] FIG. 2 shows a side view of a midsole 12 of the shoe sole,
the midsole body 10 of which has in the rear portion 14 of the heel
region 16--on each of both sides--an air inlet opening 22 and in
the midfoot region 24 and the ball/toe region 26 a total of 4 air
outlet openings 28, which are arranged successively one behind the
other in the longitudinal direction of the shoe S and overlapping
in an imbricated manner as a result of their slanted orientation
and length. The air inlet opening 22 and the air outlet openings 28
are flow-connected to one another by a ventilation channel 30 in a
way corresponding to FIG. 1; this ventilation channel has four
branch channel portions 40 on both sides.
[0028] The midsole body 10 has on its underside, which is facing an
outsole 44, a heel recess 46, in which a soft heel part 48 is
arranged. Seen in the longitudinal direction of the shoe S, this
soft heel part extends from the rear portion 14 of the heel region
16 to approximately the middle of the midsole 12 and runs over the
entire width of the midsole 12 with an at least approximately
constant cross section in the form of a convex-convex lens. In the
unloaded state, the soft heel part 48 and the midsole body 10 keep
the outsole in a form in which it is rounded in a continuously
convex manner in the longitudinal direction of the shoe sole S, as
is generally known from MBT walking devices. The soft heel part 48
has a greatest thickness of about 20 mm. Correspondingly, the
greatest thickness of the midsole body 10 is approximately 30
mm.
[0029] It should be mentioned at this point that the midsole body
10 has a peripheral bead 50, which protrudes in the upward
direction with respect to the surface 42. On the one hand, this
bead serves for fastening the midsole 12 to an upper 56 and on the
other hand the aforementioned cover 52 is arranged in the
depression delimited by the surface 42 and the bead 50.
[0030] The soft heel part is preferably produced from an open-cell
polyurethane elastomer foam (PUR Shore 30 C) and the midsole body
10 from a polyurethane elastomer (PUR Shore 58 C) or an ethylene
vinyl acetate (EVA); this applies to all the embodiments shown.
[0031] FIG. 3 shows a midsole 12 of the shoe sole that is formed
identically to that according to FIG. 2, but with the air inlet
openings 22 and the air outlet openings 28 now being of an oval
form and running in a row one behind the other in an upper
peripheral region of the midsole body 10. Here, too, the air inlet
openings 22 and the air outlet openings 28 are connected to one
another by way of a corresponding ventilation channel 30.
[0032] The elastically deformable cover 52 for the ventilation
channel 30 is preferably formed by an insole 54, which is placed
onto the upper surface 42 of the midsole body 10 and extends on all
sides as far as the bead 50 or the upper that is fastened to the
midsole body 10 and is lying against the bead 50.
[0033] The embodiment of the insole 54 that is shown in FIG. 4 has
an upper, air-permeable carrier layer 58, from which supporting
elements 60 protrude in the downward direction, in the fitted state
toward the midsole body 10, arranged in a grid pattern and at a
distance from one another. These supporting elements are preferably
formed as double cones and produced from an elastic synthetic
material. In their length, they optimally match the depressions in
the midsole body 10. In the fitted state, they rest with their free
end on the midsole body 10.
[0034] A further embodiment of the insole 54 is represented in FIG.
5. It likewise has an upper, air-permeable carrier layer 58.
Wave-shaped, elastically deformable supporting strips 62 protrude
from it in the downward direction. These strips preferably run in
planes that extend at right angles to the carrier layer 58 and
parallel to one another. In the fitted state, the supporting strips
62 rest with wave crests facing away from the carrier layer 58 on
the midsole body 10.
[0035] The supporting elements 60 or the supporting strips 62
consequently form an elastically compliant supporting layer 64 for
the carrier layer 58.
[0036] In the case of the particularly preferred embodiment of the
insole 54 that is shown in FIG. 6, the supporting layer 64 is made
in the form of a knitted spacer fabric 66. The upper side forms the
air-permeable carrier layer 58 and elastically deformable pile
threads, also known as spacer threads, run from these in the
downward direction. Knitted fabrics of this type are produced, for
example, by the company Muller Textil GmbH, Wiehl-Drabenderhohe
(DE) and are marketed under the name "3mesh". Possible embodiments
of the spacer fabric 66 are disclosed, for example, in EP 1 775 362
A and EP 1 860 218 A.
[0037] An exploded perspective representation of a preferred
embodiment of the shoe sole according to FIG. 2 is shown in FIG. 7.
The midsole body 10 is provided with the heel recess 46. The soft
heel part 48 is inserted in the heel recess 46, in the present case
filling the space. As known from MBT walking devices, the outsole
44 is fastened to the midsole body 10 and the soft heel part 48,
whereby it is kept in the convex form, compare FIGS. 2 and 3. It
consists, for example, of rubber and has a Shore A hardness of 55
to 65.
[0038] A ventilation insert element 68, which in FIG. 7 is
represented as detached from the midsole body 10, is however
integrated in the latter. Seen in plan view, the ventilation insert
element 68 has a U shape, the two parallel legs 70, 70' running in
the longitudinal direction of the shoe sole S and being connected
to one another at their rear end, seen in the walking direction L,
by way of an arc portion 72. The two legs 70, 70' and the arc
portion 72 are formed by a cross-sectionally U-shaped channel wall
74, this channel wall 74 a delimiting in the region of the legs 70,
70' a respective main channel portion 38'. The legs 70, 70' and the
arc portion 72 are open in the upward direction on the side facing
away from the outsole 44. The channel wall 74 forms a bottom part
76 as well as an inner wall part 78 and an outer wall part 80,
these two wall parts 78, 80 protruding from the bottom part 76 in
the upward direction. In the integrated state of the ventilation
insert element 68, the exposed upper periphery of the wall parts
78, 80 is in line with the upper surface 42 of the midsole body 10.
In the heel region 16, the depth of the U-shaped cross section,
measured from the free periphery of the wall parts 78, 80 to the
bottom part 76, is preferably at least 4 mm. Furthermore, the wall
parts 78, 80 are preferably at a distance from one another of at
least 8 mm. In the midfoot region 24, said depth increases in a way
corresponding to the form of the heel recess 46 and then decreases
continuously, in the direction of the end at the front in the
walking direction L.
[0039] In the arc portion 72, which in the integrated state comes
to lie in the rear portion 14 of the heel region 16, a respective
air inlet tube stub 82 protrudes from the outer wall part 80 in the
direction of the shoe sole inner side 18 and in the direction of
the shoe sole outer side 20. These stubs are flow-connected to the
main channel portions 38' and their outer free ends form the air
inlet openings 22.
[0040] Correspondingly, in the midfoot region 24 and in the
ball/toe region 26, air outlet tube stubs 84 protrude from the
outer wall part 80 in the outward direction. These, too, are
flow-connected to the assigned main channel portion 38', form the
branch channel portions 40 and, with their free ends, form the air
outlet openings 28.
[0041] The ventilation insert element 68 is preferably produced
from TPU with a Shore A hardness of 85 by the injection-molding
process.
[0042] FIG. 7 also shows a reinforcing element 86, which has at
least in the heel region 16 and midfoot region 24 such a stability
that the midsole 12 is at least approximately flexurally rigid,
with respect to loads during standing and walking, in its portion
located above the soft heel part 48. In the state in which it is
integrated in the midsole body 10, the reinforcing element 86 is
enclosed by the ventilation insert element 68. Seen in the
direction at right angles to the longitudinal direction of the shoe
sole S, the reinforcing element 86 is consequently located in a
central region of the midsole body 10, one of the two main channel
portions 38' being arranged in the direction of the shoe sole inner
side 18 and one in the direction of the shoe sole outer side
20.
[0043] The reinforcing element 86, which is likewise preferably
produced by the injection-molding process, has an upper,
tongue-shaped, plate-like carrying part 88 and a V-shaped
supporting part 90, protruding from the latter in the downward
direction. Both the carrying part 88 and the supporting part 90 are
of a double-walled form, the two walls respectively being fixedly
connected to one another by way of ribs 92. In the state in which
it is integrated in the midsole body 10, the carrying part 82 lies
close to the surface 42, as the midsole body 10 in FIG. 7
indicates; here, the reinforcing element 86 is already integrated
in the midsole body 10. It extends between the two legs 70, 70'
from the inner wall part 78 in the arc portion 72 forward in the
walking direction L into a front portion of the ball/toe region 26.
The reinforcing element 86 is preferably rigidly formed and
produced, for example, from nylon 12 in the heel region 16 and the
midfoot region 24, while it may be flexibly formed and consist, for
example, of TPU in the ball/toe region 26.
[0044] The supporting part 90 is likewise stably formed, the rear
leg 90', seen in the walking direction L, of the supporting part 90
being shaped in a way corresponding to the heel recess 46 and this
rear leg 90' meeting the front leg 90'' at the front end, seen in
the walking direction L, of the heel recess 46, where it forms a
tilting edge 94.
[0045] The prefabricated reinforcing element 86 and the
prefabricated ventilation insert element 68 may be placed in a
cavity of an injection mold for the injection-molding of the
midsole body 10, injection of PUR Shore 58 C, for example, taking
place after the mold has been closed for the purpose of molding the
midsole body 10. In this case, the injection mold may have
supporting ribs for the channel wall 74 and slides engaging in the
air inlet tube stubs 82 and the air outlet tube stubs 84, in order
to prevent the ventilation insert element 68 from being compressed
during the injection-molding of the midsole body 10.
[0046] As a result of the exploded representation, the midsole body
10 shown in FIG. 7 has depressions and clearances that are formed
to match the ventilation insert element 68.
[0047] Furthermore, FIG. 7 shows the insole 54, which forms the
cover 52 and . . . onto the surface 42 formed by the midsole body
10, possibly the reinforcing element 86 and the exposed face of the
outer wall part 80 and inner wall part 78.
[0048] Around the periphery, the insole 54 is enclosed by the
relatively high bead 50. The carrier layer 58 of the insole 54 is
preferably formed in the manner of a footbed and is correspondingly
adapted to the thickness of the supporting layer 64. Furthermore,
the surface 42 has between the outer wall part 80 and the bead 50 a
continuous strip-like surface part 42', both on the shoe sole inner
side 18 and on the shoe sole outer side 20, so that the supporting
layer 64 is supported peripherally along the bead 50 by way of the
reinforcing element 86 in a wide middle portion over the entire
length of the midsole body 10.
[0049] FIGS. 8 and 9 show a further possible embodiment of the
reinforcing element 86 for a midsole 12 according to FIG. 2 or 3,
which is formed with a ventilation channel 30 corresponding to FIG.
1.
[0050] In FIG. 10, the reinforcing element 86 is shown in a
perspective representation obliquely from above. Its task is
precisely the same as that described above in connection with the
embodiment according FIG. 7 and known from MBT walking devices. In
FIGS. 8 and 9, the outlines of the midsole 12 are indicated and the
reinforcing element 86 is shown in a dark color.
[0051] In the heel region 16, the sheet-like reinforcing element 86
runs in the midsole body 10 along the heel recess 46 and, in the
midfoot region 24 and in a rear portion of the ball/toe region 26,
seen in walking direction L, it runs in the interior of the midsole
body 10 at a distance below the ventilation channel 30. Since the
wall thickness of the midsole body 10 between the heel recess 46
and the surface 42 is much smaller in the heel region 16 than in
the midfoot region 24 and the ball/toe region 26, the insertion of
the reinforcing element 86 known from MBT walking devices could
lead to an inadequate depth of the ventilation channel 30 in the
heel portion 32. This is particularly clear from FIG. 9, where the
ventilation channel 30 is shown colored gray. In order to
counteract the stated disadvantage, the reinforcing element 86 has
in the heel region 16 a channel-like recess 96, which is V-shaped
in plan view and corresponds to the heel portion 32. In order
nevertheless to ensure the necessary flexural rigidity of the
reinforcing element 86, it may, for example, have supporting ribs
running on the underside along the webs 100 that separate the
clearances 98 from one another. Even if they protrude into the soft
heel part 48, because of their small height, they do not change the
behavior of the shoe sole or the properties thereof. It is also
possible to form the reinforcing element 86 in the heel region 16
from a more stable material.
[0052] In the case of a shoe sole according to FIG. 7, it is
conceivable not to use a ventilation insert element 68, but to mold
the depression for forming the main channel portions 38' and the
connection thereof in the arc portion 72 by a rib from the
injection mold, and to mold the branch channel portions directly on
the midsole body 10 by means of slides.
[0053] During walking with a shoe sole shown in the figures and
described above, when the heel region 16 is put down during a step,
on the one hand the soft heel part 48 is compressed, which greatly
reduces shocks on the user's body, and on the other hand the cover
52 in the heel region 16 is also deformed in the direction of the
midsole body 10. This leads to a local constriction of the cross
section that is delimited by the midsole 10 and the cover 52, or
the carrier layer 58 thereof, and is filled with air. As a result
of the rolling action on the ground, this constricted cross section
is displaced in the walking direction L over the midfoot region 24
into the ball/toe region 26. This shifting of the constriction from
the heel region 16 into the ball/toe region 26 leads to the
expulsion of air from the ventilation channel 30 through the air
outlet openings 38, whereas, after tilting about the tilting edge
94, or the tilting edge formed by the midsole body 10 at the front
end of the heel recess 46, the cover 52 or the insole 54 is
relieved of load in the heel region 16, which leads to a widening
of the cross section again behind the constriction as a result of
the elasticity of the cover 52 or the insole 54, whereby fresh air
is sucked into the ventilation channel 30 through the air inlet
openings 22. During walking, air is consequently made to pass
through the midsole 12 in a ventilating manner on the basis of a
purely mechanical principle. This warmed-up air is expelled through
the air outlet openings 28 while fresh, cool air is sucked in
through the air inlet openings 22.
[0054] If the cover 52 or the insole 54 is of an air-permeable
form, cool air is also correspondingly forced against the user's
foot.
* * * * *