U.S. patent application number 09/754063 was filed with the patent office on 2001-07-12 for shoe with viscoelastic interior liner.
This patent application is currently assigned to SALOMON S.A.. Invention is credited to Bordin, Mario, Danezin, Jean-Bruno.
Application Number | 20010007180 09/754063 |
Document ID | / |
Family ID | 8845793 |
Filed Date | 2001-07-12 |
United States Patent
Application |
20010007180 |
Kind Code |
A1 |
Bordin, Mario ; et
al. |
July 12, 2001 |
Shoe with viscoelastic interior liner
Abstract
A shoe whose upper has an interior liner with a layer contiguous
to the foot, provided with a structure having of a viscoelastic
substance assembled to a flexible and elastic film. The substance
is characterized in that the viscoelastic substance is provided
with a high elastic deformation capacity with a low elastic
modulus, and in that it is obtained in a thickness from 1 to 5
millimeters. The layer thus structured tends to flatten naturally
on the foot and behaves in the manner of a "double skin" that
filters the vibrations and the impacts, and which absorbs the micro
displacements while preserving the transmission of the tactile
sensations.
Inventors: |
Bordin, Mario; (Asolo,
IT) ; Danezin, Jean-Bruno; (Chilly, FR) |
Correspondence
Address: |
GREENBLUM & BERNSTEIN
1941 ROLAND CLARKE PLACE
RESTON
VA
20191
|
Assignee: |
SALOMON S.A.
Metz-Tessy
FR
|
Family ID: |
8845793 |
Appl. No.: |
09/754063 |
Filed: |
January 5, 2001 |
Current U.S.
Class: |
36/93 ; 36/10;
36/55 |
Current CPC
Class: |
A43B 5/0405 20130101;
A43B 23/07 20130101; A43B 17/026 20130101 |
Class at
Publication: |
36/93 ; 36/10;
36/55 |
International
Class: |
A43B 023/07 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 7, 2000 |
FR |
00 00301 |
Claims
What is claimed is:
1. A shoe comprising: an upper having an interior liner with a
layer contiguous to a user's foot, said liner including, at least
over a predetermined zone, with a structure comprising a
viscoelastic substance bonded to a flexible and elastic film, said
flexible and elastic film being adapted to be in direct contact
with the foot, said viscoelastic substance being a non-compressible
material and having a low elastic modulus, said viscoelastic
substance being in the form of a thin sheet of polymer gel having a
density comprised between about 1 and 2 g/cm.sup.3, and a behavior
characterized by a "delayed" elasticity and an elongation at break
capacity greater than 400%.
2. A shoe according to claim 1, wherein the viscoelastic substance
is characterized by an elongation at break capacity comprised
between about 700 and about 900%.
3. A shoe according to claim 1, wherein the viscoelastic substance
comprises a thickness comprised between about 2 and 5
millimeters.
4. A shoe according to claim 1, wherein the viscoelastic substance
is contained in an envelope made of a flexible and elastic
film.
5. A shoe according to claim 1, wherein the interior liner covers a
comfort padding that is inserted between the viscoelastic substance
and the boot upper.
6. A shoe according to claim 5, wherein the viscoelastic substance
is partially housed in the comfort padding on a side directed
toward the user's foot.
7. A shoe according to claim 6, wherein the layer of the interior
liner that is contiguous to the foot comprises a plurality of
predetermined zones each provided with a structure composed of a
viscoelastic substance bonded to a flexible and elastic film.
8. A shoe according to claim 7, wherein each of the predetermined
zones has a structure which, composed of a viscoelastic substance
bonded to a flexible and elastic film, has a different thickness
from a predetermined zone to another predetermined zone.
9. A shoe according to claim 1, wherein the viscoelastic substance
has an Asker C hardness from about 15 to about 45.
10. A shoe according to claim 1, wherein the viscoelastic substance
has an Asker C hardness from about 25 to about 30.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to shoes in general, whether
they have a flexible or rigid upper, and relates to an interior
liner of their upper adapted, among other things, to contribute to
the comfort of the foot and to ensure the contact with the latter
to hold it.
[0003] 2. Description of Background and Relevant Information
[0004] Conventionally, and depending on the type of shoe, the
interior liner is assembled either on an inserted padding element
or comfort cushion, or directly on the upper. More specifically, in
the case of shoes having a relatively high upper, such as ski or
hiking boots, the liner is assembled on the inside of a padding
element, such as a removable or fixed sock that is inserted between
the upper and the foot. Conversely, in the case of sports shoes
with a flexible upper, such as tennis shoes, basketball shoes,
running shoes, etc., the interior liner is assembled directly on
the upper.
[0005] Furthermore, to respect the morphology of the foot as much
as possible for the comfort thereof, the interior liner of these
various types of shoes almost generally has one or several
relatively flexible and/or elastic pieces of fabric or skin on the
side contiguous to the foot. Conventionally, these pieces of fabric
are composites resulting from the coating or adhesion of a very low
density foam on the wrong side of a textile. They are thus capable
of conforming to the upper and/or the padding element on which they
are assembled, and also capable of deforming subsequently on the
foot when the shoe is closed on the latter. The pieces of fabric
further procure softness to the touch and a pleasant sensation when
putting on the shoe. However, they prove inefficient in dispersing
or attenuating any overpressure or hard spot between the upper and
the foot, because of their low density and the fact that they
compress very easily.
[0006] By way of example, U.S. Pat. Nos. 3,977,098 and 5,765,296
can be cited, which describe a shoe having a rigid upper and a shoe
having a flexible upper, respectively, provided with an interior
liner having at least one flexible piece of fabric on the side
contiguous to the foot, as disclosed previously.
[0007] As is clearly apparent from this prior art, the contact of
the interior liner with the foot occurs more or less closely,
depending upon whether the boot upper itself is flexible and
deformable, and/or whether the padding element inserted between the
upper and the foot can conform to the foot. By way of example, U.S.
Pat. No. 3,977,098 specifically discloses a solution for
adjusting/adapting a padding element, such as an inner sock, coated
with a fabric layer on the foot. As is taught, lateral wedges,
possibly in the form of impervious packings containing a deformable
material, are introduced in pockets located on the outer surface of
the padding to adjust the width of the fitting volume to the foot,
and thus to ensure that the latter is held in the rigid upper of
the boot.
[0008] This method of using a lateral wedging adapted to move the
padding toward the foot requires that this padding be made out of a
material that can compress easily, if adjusting to the foot is what
is desired, or made out of a relatively firm material, if holding
the foot is what is preferred. Indeed, a given padding cannot be
both easily deformable, for enveloping the foot, and firm, for
holding it without slack.
[0009] In the present case, this problem is partially resolved due
to the fact that the padding, which is made of polyurethane or foam
rubber, therefore compressible, is obtained from a rough shape
forming a pair of side panels, and to the fact that it is a lateral
wedging in the area of the ankle. Because the rough shape of the
padding originally has forms that correspond approximately to the
forms of the foot, it is not necessary to firmly tighten the
padding on the foot to hold it, because the most projecting
portions thereof are housed in the rough shape; moreover, to
essentially resolve a problem of lateral wedging, the latter does
not require the padding to be closely adjusted, for an approximate
coming together of the side panels of its rough shape on the foot
suffices to ensure its adjusting to the width of the foot. This
wedging and/or adjusting method therefore proves satisfactory, but
within strict limits, because the padding does not make it possible
to ensure an enveloping/adjusting that accurately assumes the shape
of the foot; however, the lack of close contact with the foot
considerably blurs the tactile perceptions thereof and therefore
disturbs the movements of the boot's wearer, especially when this
involves boots secured to equipment or accessories, such as skis,
roller skates or ice skates, studs, etc., which are necessary to
practice a sport.
[0010] Furthermore, the thinness of the pieces of fabric that cover
the padding as well as their texture have no ability to absorb any
projecting portion of the foot, and no ability to disperse the
pressures which the padding can apply locally on the protruding
portions of the foot. Moreover, during use of the boot, and
depending on the loads to which the foot is subject, the
displacements of the latter with respect to the padding, despite
their low amplitude, are not accompanied by these pieces of fabric.
As a result, frictions are generated which often constitute a
source of blisters, irritations and burning sensations.
[0011] In the example of the shoe described in U.S. Pat. No.
5,765,296, the problem of holding the foot and of adjusting the
interior liner on the foot arises in a different manner, because
this shoe has a flexible upper provided with foam paddings. Indeed,
in a shoe of this type, it is the combination of the flexibility of
the upper, the compressibility of the paddings, and the tightening
force applied on the lacing that conditions the holding of the foot
and the enveloping of the form thereof. The pieces of fabric that
cover the interior liner on the side contiguous to the foot also
participate in enveloping the foot and, to this end, are made of a
soft felt-like material to facilitate the insertion of the foot
into the boot. However, as in the case of the padding described and
taught in U.S. Pat. No. 3,977,098, these pieces of fabric are too
thin and have an overly soft and felt-like texture to contribute to
holding the foot in the boot, as well as to absorb any projecting
portion of the foot. In addition, due to their close linkage with
the boot upper, the deformations which the foot imposes on the
latter when walking, running, jumping, etc., and their repetition,
ultimately cause these pieces of fabric to delaminate and/or
separate. This deterioration that results from pressuring the
pieces of fabric against the foot, and from their inability to
accompany the latter along these micro displacements, in relation
to the upper, further promotes frictions which constitute a source
of irritation, burnings, blisters, etc.
SUMMARY OF THE INVENTION
[0012] An object of the present invention is to overcome the
disadvantages of the known interior liners and, in particular, it
is an object to provide an interior liner which, due to a layer
contiguous to the foot, is capable of conforming to the small
protuberances and/or projections extending to the surface of the
latter, and of accompanying the foot along its micro displacements
in relation to the boot upper.
[0013] According to the invention, the layer contiguous to the foot
has, at least over a predetermined zone, a structure composed of a
viscoelastic substance assembled on a flexible and extensible film,
such as a fabric, for example. This structure constitutes the
equivalent of a double skin due, in particular, to the thinness and
the high elastic deformability of the viscoelastic substance
combined with a low elastic modulus. These various characteristics
impart to the viscoelastic substance, and thus to the structure of
the layer contiguous to the foot, a typical behavior of a so-called
"delayed" elasticity, and a natural tendency to lay flat on the
foot, in the manner of a viscous gel, by conforming to the small
protuberances thereof.
[0014] In this way, the micro displacements of the foot with
respect to the boot upper are essentially absorbed by the
viscoelastic structure of the layer contiguous to the foot. In
fact, the layer thus structured constitutes the interface element
between the foot and the boot upper which, possibly mounted on
padding, filters the vibrations, the impacts, etc., absorbs the low
amplitude displacements, and prevents from involving the skin of
the foot to a certain extent, while preserving the transmission of
the tactile sensations.
[0015] According to one characteristic, the interior liner includes
a layer contiguous to the foot constituted, at least over a
predetermined zone, of a structure composed of a non-compressible
viscoelastic substance having a low elastic modulus and a flexible
and elastic film that can be a woven or non-woven material on which
the latter is fixed. According to one mode of construction, the
viscoelastic substance is contained in an envelop obtained by means
of a flexible and elastic film.
[0016] The viscoelastic substance is, for example, a polymer gel
having a density comprised between about 1 and 2 g/cm.sup.3, and
whose behavior is characterized by a "delayed" elasticity and by an
elongation at break capacity greater than 400%, preferably on the
order of 700-900%. According to another characteristic, the
viscoelastic substance has an Asker C hardness, or a resistance to
deformation and penetration, from 15 to 45, preferably from 25 to
30. This hardness is measured with Asker durometers adapted to
substances classified as soft rubbers and plastics, including
flexible cellular materials and elastomers, according to the SRIS
0101 standard (Society of Rubber Ind. Japanese Standard). Due to
these characteristics, the viscoelastic substance can deform under
the effect of a stress in the manner of a viscous fluid, because
its elongation capacity is substantial, and can recover its initial
form as a spring, but after a certain period of time after the
stress has ceased, for its modulus elasticity is low.
[0017] In fact, this gel-like substance behaves like a viscous
product for slow stresses, and an elastic product for rapid
stresses.
[0018] According to a preferred embodiment, the viscoelastic
substance is obtained in the form of a thin sheet with a thickness
close to 1 millimeter, and on the order of 5 millimeters
maximum.
[0019] Its bonding with the flexible film is obtained by adhesive,
stitching, welding, etc.
[0020] These various characteristics of viscoelasticity, thickness,
and bonding on the flexible film impart to the structure a
flexibility that is comparable to that of the pieces of fabric used
traditionally, and a certain homogeneity and stability. In
particular, gravity flow of the viscoelastic substance is avoided
while allowing its deformation under pressure when the boot upper
is tightened on the foot.
[0021] According to an embodiment, the layer contiguous to the foot
is provided with a structure composed of a viscoelastic substance
bonded to a flexible film on at least one zone of the foot having
bone protuberances.
[0022] According to another embodiment, the layer contiguous to the
foot includes a plurality of predetermined zones each provided with
a structure composed of a viscoelastic substance fixed to a
flexible film.
[0023] According to an alternative construction of this embodiment,
the structure composed of a viscoelastic substance bonded to a
flexible film has a different thickness from one predetermined zone
to another predetermined zone. For example, in the zones where the
bone protuberances of the foot are very pronounced, it is a
structure where the viscoelastic substance is relatively thick, for
example 4-5 millimeters, that is implemented. In this way,
localization of pressure spots is avoided due to the configuration
of this structure on a large contact surface.
BRIEF DESCRIPTION OF DRAWINGS
[0024] The invention will be better understood from the description
that follows, with reference to the annexed schematic drawings
showing two embodiments, by way of example, and in which:
[0025] FIG. 1 shows a perspective view of a boot of the rigid shell
type equipped with a comfort padding having an interior liner
according to the invention.
[0026] FIG. 2 shows the boot of FIG. 1, seen in a cross-section
along the line II-II, with the user's foot positioned therein.
[0027] FIG. 3 shows a cross-sectional view of a detail of the
interior liner of the boot.
[0028] FIG. 4 shows a perspective view of a boot having a flexible
upper, also equipped with an interior liner according to the
invention.
[0029] FIG. 5 is a transverse cross-sectional view along the line
V-V of the boot of FIG. 4.
[0030] FIGS. 6 and 7 show a mode of construction of an interior
liner, or lining, before assembly on the upper of a boot, FIG. 6
showing the flat developed liner, and FIG. 7 showing a
cross-section along the line VII-VII of the liner of FIG. 6.
DETAILED DESCRIPTION OF THE INVENTION
[0031] The boot shown in FIGS. 1 and 2 is a ski boot with a rigid
upper 1 provided with a comfort padding 2, constituted by a liner,
which is inserted between the user's foot 4 and the upper 1. In a
known manner, this padding 2 is made out of a microcellular
material having a density of less than 1, more or less
compressible, such as polyurethane or foam rubber, and has a rough
shape having the fitting volume corresponding approximately to the
standard fitting volume of a foot 4 in a given size.
[0032] According to an essential characteristic, the padding 2 is
covered by an interior liner, one layer 3 of which, contiguous to
the foot 4, is provided with a structure 5 where a thin sheet of a
viscoelastic substance 6 having a low elastic modulus is bonded to
a flexible and elastic film 7. This viscoelastic substance 6 is
constituted, for example, by a polymer gel having a density
comprised between 1 and 2, and its behavior is characterized by a
"delayed" elasticity and an elongation at break capacity greater
than 400%, and preferably comprised between 700 and 900%. Its
hardness, measured with an Asker durometer, is comprised between 15
and 45 Asker C, preferably between 25 and 30 Asker C. With respect
to measurements, the thin sheet of viscoelastic substance 6 has a
thickness of approximately 2 millimeters and can reach 5
millimeters.
[0033] With these arrangements, the structure 5 of the layer 3
maintains a flexibility that is substantially comparable to that of
the pieces of fabric used traditionally, i.e., it can cover the
padding 2 by accurately following its forms, and accompany its
subsequent deformations when the upper 1 is tightened to close the
boot on the user's foot 4. Conversely, because of its
non-compressibility combined with its high elongation at break
capacity and its density that is greater than that of the padding
2, this structure 5 can conform to the small protuberances of the
foot which are not taken into account by the rough shape of the
fitting volume offered by the padding 2. Furthermore, when the
latter is pressed on the foot 4, via the upper 1 during closure of
the boot, the viscoelastic substance 6 of the structure 5 deforms
in the manner of a viscous fluid, thinning out in the area where
pressures are the highest and thickening in the neighboring space
subject to lower pressures. As a result from this behavior, there
is a close contact between the structure 5 of the layer 3 and the
foot 4, and thus an increased holding sensation that enables the
boot user to make more precise movements.
[0034] In fact, a relatively dense and non-compressible layer 3-5
is placed in contact with the foot 4, and a less dense and
compressible padding element between this layer 3-5 and the upper
1. In this manner, the layer 3, with its structure 5, plays the
role of a double skin because it conforms accurately to the foot,
and its high elasticity enables it to accompany the micros
displacements of the foot with respect to the upper 1 of the boot,
and even with respect to the padding 2. Thus, the frictions that
can be generated between the flexible film 7 and the foot 4 are
avoided.
[0035] In the example shown in FIGS. 4 and 5, the interior liner
including a layer 3 provided with a structure 5, as described with
reference to FIGS. 1, 2, and 3, adapted to a shoe having a flexible
upper 11. In this case, the layer 3 with a structure 5 is mounted
directly on the flexible upper 11 whose contour it follows.
Preferably, in view of the fact that the flexible upper 11 adjusts
very easily to the user's foot when the boot is closed, and for
weight considerations, the structure 5 is provided with a
viscoelastic substance in the form of a thin sheet whose thickness
is on the order of 1 millimeter. In this way, the ease of
adjustment of the upper 11 of the boot is preserved without overly
weighing down the latter.
[0036] Nothing prevents using a comfort padding 15 on the flexible
upper 11, for example, on the upper edge of the opening for
inserting the foot, and from covering this padding 15 or not with
the structure 5 of the layer 3.
[0037] FIGS. 6 and 7 show a mode of construction of an interior
liner, one layer 3 of which, provided with a structure 5, is
associated with a support piece 22 that can constitute a comfort
padding. This support piece, possibly configured to nest the
viscoelastic substance 6, is fixed to the flexible film 7 of the
structure 5, for example, by adhesion of hot-melt films. To
facilitate the assembly of this interior liner on the upper of a
boot, not shown, the zone 23 adapted to be sewn and/or stitched,
such as the edge, is not provided with a viscoelastic substance
6.
[0038] Numerous other adaptations of a structure 5 close to the
foot can be envisioned without leaving the scope of the invention.
Thus, the viscoelastic substance 6 of the structure 5 can be
housed, at least partially, in the comfort padding 2 on the side
directed toward the foot 4 of the user. Moreover, the layer 3
contiguous to the foot can be provided with a structure 5 composed
of a viscoelastic substance bonded to a flexible film 7, or bonded
to any other textile having equivalent properties, over only a
portion of the foot having bone protuberances.
[0039] Furthermore, the layer 3 contiguous to the foot can include
a plurality of predetermined zones each provided with a structure 5
composed of a viscoelastic substance 6 fixed to a flexible film 7
or a textile, and this structure can have a different thickness
from one predetermined zone to another predetermined zone. By way
of example, the structure 5 could be localized in the zones 12 and
13 corresponding to the malleoli 12' and 13' of the foot 4.
[0040] Finally, a layer 3 provided with a structure 5 can of course
constitute the interior liner of a tongue of a comfort padding or
of a sock, and/or the tongue 14 coming from the boot upper.
[0041] The instant application is based upon French Patent
Application No. 00 00301, filed Jan. 7, 2000, the disclosure of
which is hereby incorporated by reference thereto in its entirety,
and the priority of which is hereby claimed under 35 U.S.C.
.sctn.119.
* * * * *